89 results on '"Lin Hua Zhang"'
Search Results
2. Increasing the Targeting Scope of CRISPR Base Editing System Beyond NGG
- Author
-
Si-Yue, Yu, Alexandra, Birkenshaw, Tyler, Thomson, Tiffany, Carlaw, Lin-Hua, Zhang, and Colin J D, Ross
- Subjects
Gene Editing ,Nucleotides ,Genetics ,Humans ,DNA Breaks, Double-Stranded ,DNA ,CRISPR-Cas Systems ,Biotechnology - Abstract
Genome editing provides a new therapeutic strategy to cure genetic diseases. The recently developed CRISPR-Cas9 base editing technology has shown great potential to repair the majority of pathogenic point mutations in the patient's DNA precisely. Base editor is the fusion of a Cas9 nickase with a base-modifying enzyme that can change a nucleotide on a single strand of DNA without generating double-stranded DNA breaks. However, a major limitation in applying such a system is the prerequisite of a protospacer adjacent motif sequence at the desired position relative to the target site. Progress has been made to increase the targeting scope of base editors by engineering SpCas9 protein variants, establishing systems with broadened editing windows, characterizing new SpCas9 orthologs, and developing prime editing technology. In this review, we discuss recent progress in the development of CRISPR base editing, focusing on its targeting scope, and we provide a workflow for selecting a suitable base editor based on the target nucleotide sequences.
- Published
- 2022
- Full Text
- View/download PDF
3. CRISPR/Cas9 Editing: Sparking Discussion on Safety in Light of the Need for New Therapeutics
- Author
-
Colin J. D. Ross, Lin-Hua Zhang, and Tiffany Marie Carlaw
- Subjects
Gene Editing ,Genome, Human ,Genetic enhancement ,Genetic Therapy ,Computational biology ,Biology ,DNA sequencing ,Mutation ,parasitic diseases ,Genetics ,Humans ,Molecular Medicine ,CRISPR ,CRISPR-Cas Systems ,Molecular Biology - Abstract
Recent advances in genome sequencing have greatly improved our ability to understand and identify the causes of genetic diseases. However, there remains an urgent need for innovative, safe, and effective treatments for these diseases. CRISPR-based genome editing systems have become important and powerful tools in the laboratory, and efforts are underway to translate these into patient therapies. Therapeutic base editing is one form of genome engineering that has gained much interest because of its simplicity, specificity, and effectiveness. Base editors are a fusion of a partially deactivated Cas9 enzyme with nickase function, together with a base-modifying enzyme. They are capable of precisely targeting and repairing a pathogenic mutation to restore the normal function of a gene, ideally without disturbing the rest of the genome. In the past year, research has identified new safety concerns of base editors and sparked new innovations to improve their safety. In this review, we provide an overview of the recent advances in the safety and effectiveness of therapeutic base editors and prime editing.
- Published
- 2020
- Full Text
- View/download PDF
4. Niacin increases HDL biogenesis by enhancing DR4-dependent transcription of ABCA1 and lipidation of apolipoprotein A-I in HepG2 cells
- Author
-
Lin-Hua Zhang, Vaijinath S. Kamanna, Shobha H. Ganji, Xi-Ming Xiong, and Moti L. Kashyap
- Subjects
high density lipoproteins ,apolipoprotein A-I ,ATP binding cassette transporterA1 ,direct repeat 4 ,HDL biogenesis ,human hepatoblstoma cell line ,Biochemistry ,QD415-436 - Abstract
The lipidation of apoA-I in liver greatly influences HDL biogenesis and plasma HDL levels by stabilizing the secreted apoA-I. Niacin is the most effective lipid-regulating agent clinically available to raise HDL. This study was undertaken to identify regulatory mechanisms of niacin action in hepatic lipidation of apoA-I, a critical event involved in HDL biogenesis. In cultured human hepatocytes (HepG2), niacin increased: association of apoA-I with phospholipids and cholesterol by 46% and 23% respectively, formation of lipid-poor single apoA-I molecule-containing particles up to ∼ 2.4-fold, and pre β 1 and α migrating HDL particles. Niacin dose-dependently stimulated the cell efflux of phospholipid and cholesterol and increased transcription of ABCA1 gene and ABCA1 protein. Mutated DR4, a binding site for nuclear factor liver X receptor alpha (LXR α ) in the ABCA1 promoter, abolished niacin stimulatory effect. Further, knocking down LXR α or ABCA1 by RNA interference eliminated niacin-stimulated apoA-I lipidation. Niacin treatment did not change apoA-I gene expression. The present data indicate that niacin increases apoA-I lipidation by enhancing lipid efflux through a DR4-dependent transcription of ABCA1 gene in HepG2 cells. A stimulatory role of niacin in early hepatic formation of HDL particles suggests a new mechanism that contributes to niacin action to increase the stability of newly synthesized circulating HDL.
- Published
- 2012
- Full Text
- View/download PDF
5. Pioglitazone increases apolipoprotein A-I production by directly enhancing PPRE-dependent transcription in HepG2 cells
- Author
-
Lin-Hua Zhang, Vaijinath S. Kamanna, Shobha H. Ganji, Xi-Ming Xiong, and Moti L. Kashyap
- Subjects
HDL/metabolism ,atherosclerosis ,nuclear receptors ,cholesterol ,Biochemistry ,QD415-436 - Abstract
Pioglitazone, a hypoglycemic agent, has been shown to increase plasma HDL cholesterol, but the mechanism is incompletely understood. We further investigated effects of pioglitazone on transcriptional regulation of apolipoprotein (apo)A-I gene and functional properties of pioglitazone-induced apoA-I-containing particles. Pioglitazone dose-dependently stimulated apoA-I promoter activities in HepG2 cells. A peroxisome proliferator-activated receptor (PPAR)-response element located in site A (−214 to −192 bp, upstream of the transcription start site) of the promoter is required for pioglitazone-induced apoA-I gene transcription. Deletion of site A (−214 to −192 bp), B (−169 to −146 bp), or C (−134 to −119 bp), which clusters a number of cis-acting elements for binding of different transcription factors, reduced the basal apoA-I promoter activities, and no additional pioglitazone-sensitive elements were found within this region. Overexpression or knock-down of liver receptor homolog-1, a newly identified nuclear factor with strong stimulatory effect on apoA-I transcription, did not alter pioglitazone-induced apoA-I transcription. Pioglitazone-induced apoA-I transcription is mainly mediated through PPARα but not PPARγ in hepatocytes. Pioglitazone induced production of HDL enriched in its subfraction containing apoA-I without apoA-II, which inhibited monocyte adhesion to endothelial cells in vitro. In conclusion, pioglitazone increases apoA-I production by directly enhancing PPAR-response element-dependent transcription, resulting in generation of apoA-I-containing HDL particles with increased anti-inflammatory property.
- Published
- 2010
- Full Text
- View/download PDF
6. Niacin inhibits surface expression of ATP synthase β chain in HepG2 cells: implications for raising HDL
- Author
-
Lin-Hua Zhang, Vaijinath S. Kamanna, Michael C. Zhang, and Moti L. Kashyap
- Subjects
hepatocytes ,HDL receptor ,nicotinic acid ,flow cytometry ,Biochemistry ,QD415-436 - Abstract
Niacin is an effective agent for raising HDL, but its cellular target sites are largely unknown. We examined effects of niacin on the surface expression of ATP synthase β chain, a newly described HDL/apolipoprotein A-I (apoA-I) receptor for HDL endocytosis, in HepG2 cells. A significant amount of immunodetectable β chain was observed on the surface of HepG2 cells, which was competitively displaced by apoA-I. Niacin treatment reduced the surface expression of β chain in HepG2 cells by ∼27%, and decreased 125I-labeled HDL uptake up to ∼35%. However, nicotinamide, a niacin metabolite that does not have clinical lipid effects, exhibited weaker inhibition on the β chain cell surface expression, and failed to show inhibitory action on 125I-labeled HDL uptake. Furthermore, anti-β chain antibody significantly reduced 125I-labeled HDL uptake and abolished the inhibitory effect of niacin. Niacin did not change β chain mRNA expression. These data suggest that niacin inhibits cell surface expression of the ATP synthase β chain, leading to reduced hepatic removal of HDL protein, thus implicating a potential cellular target for niacin action to raise HDL.
- Published
- 2008
- Full Text
- View/download PDF
7. Truncation mutations in ABCA1 suppress normal upregulation of full-length ABCA1 by 9-cis-retinoic acid and 22-R-hydroxycholesterol
- Author
-
Cheryl L. Wellington, Yu-Zhou Yang, Stephen Zhou, Susanne M. Clee, Bing Tan, Kenichi Hirano, Karin Zwarts, Anita Kwok, Allison Gelfer, Michel Marcil, Scott Newman, Kirsten Roomp, Roshni Singaraja, Jennifer Collins, Lin-Hua Zhang, Albert K. Groen, Kees Hovingh, Alison Brownlie, Sherrie Tafuri, Jacques Genest, Jr., John J.P. Kastelein, and Michael R. Hayden
- Subjects
high density lipoprotein cholesterol ,cholesterol efflux ,pharmacogenomics ,Biochemistry ,QD415-436 - Abstract
Mutations in ABCA1 uniformly decrease plasma HDL-cholesterol (HDL-C) and reduce cholesterol efflux, yet different mutations in ABCA1 result in different phenotypic effects in heterozygotes. For example, truncation mutations result in significantly lower HDL-C and apoliprotein A-I (apoA-I) levels in heterozygotes compared with nontruncation mutations, suggesting that truncation mutations may negatively affect the wild-type allele. To specifically test this hypothesis, we examined ABCA1 protein expression in response to 9-cis-retinoic acid (9-cis-RA) and 22-R-hydroxycholesterol (22-R-OH-Chol) in a collection of human fibroblasts representing eight different mutations and observed that truncation mutations blunted the response to oxysterol stimulation and dominantly suppressed induction of the remaining full-length allele to 5–10% of wild-type levels. mRNA levels between truncation and nontruncation mutations were comparable, suggesting that ABCA1 expression was suppressed at the protein level. Dominant negative activity of truncated ABCA1 was recapitulated in an in vitro model using transfected Cos-7 cells. Our results suggest that the severe reduction of HDL-C in patients with truncation mutations may be at least partly explained by dominant negative suppression of expression and activity of the remaining full-length ABCA1 allele.These data suggest that ABCA1 requires a physical association with itself or other molecules for normal function and has important pharmacogenetic implications for individuals with truncation mutations.
- Published
- 2002
- Full Text
- View/download PDF
8. Identification and functional analysis of a naturally occurring E89K mutation in the ABCA1 gene of the WHAM chicken
- Author
-
Alan D. Attie, Yannick Hamon, Angela R. Brooks-Wilson, Mark P. Gray-Keller, Marcia L.E. MacDonald, Veronique Rigot, Angie Tebon, Lin-Hua Zhang, Jacob D. Mulligan, Roshni R. Singaraja, J.James Bitgood, Mark E. Cook, John J.P. Kastelein, Giovanna Chimini, and Michael R. Hayden
- Subjects
HDL ,hypoalphalipoproteinemia ,Tangier Disease ,Biochemistry ,QD415-436 - Abstract
The Wisconsin hypoalpha mutant (WHAM) chicken has a >90% reduction in plasma HDL due to hypercatabolism by the kidney of lipid-poor apoA-I. The WHAM chickens have a recessive white skin phenotype caused by a single-gene mutation that maps to the chicken Z-chromosome. This corresponds to human 9q31.1, a chromosomal segment that contains the ATP-binding cassette protein-1 (ABCA1) gene, which is mutated in Tangier Disease and familial hypoalphalipoproteinemia. Complete sequencing of the WHAM ABCA1 cDNA identified a missense mutation near the N-terminus of the protein (E89K). The substitution of this evolutionary conserved glutamate residue for lysine in the mouse ABCA1 transporter leads to complete loss of function, resulting principally from defective intracellular trafficking and very little ABCA1 reaching the plasma membrane.The WHAM chicken is a naturally occurring animal model for Tangier Disease.
- Published
- 2002
- Full Text
- View/download PDF
9. Long-Distance PCR-Based Strategy for Preparing Knock-In Vectors Directly from ES Cell Genomic DNA
- Author
-
Lin-Hua Zhang and Howard E. Henderson
- Subjects
Biology (General) ,QH301-705.5 - Published
- 1998
- Full Text
- View/download PDF
10. Effects of AHLs inhibitors and exogenous AHLs on the stability and activity of Anammox granules at low temperatures
- Author
-
Jie-Ya He, Jun Li, Peng Sun, Lin-hua Zhang, and Jing Zhang
- Subjects
Average diameter ,Sewage ,Chemistry ,Ecological Modeling ,Temperature ,food and beverages ,Quorum Sensing ,02 engineering and technology ,010501 environmental sciences ,Acyl-Butyrolactones ,Operation temperature ,01 natural sciences ,Pollution ,Quorum sensing ,Bioreactors ,020401 chemical engineering ,Anammox ,Biophysics ,Environmental Chemistry ,0204 chemical engineering ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
This study investigated the relationship between acyl homoserine lactones (AHLs)-based quorum sensing (QS) and the properties of Anammox granular sludge at low temperatures (11-23°C). Results indicated that adding different concentrations of AHLs inhibitors reduced the content of N-hexanoyl-dl-homoserine lactone (C6-HSL) and N-octanoyl-dl-homoserinelactone (C8-HSL) in Anammox granules on different degrees at different operation temperatures, which led to the deterioration of granules stability and activity. The important role of endogenous C6-HSL and C8-HSL signals in maintaining Anammox granular sludge stability and activity in low-temperature conditions was revealed. In addition, in the process of reducing operation temperatures, another type of AHL signal (N-(3-oxooctanoyl)-l-homoserine lactone, 3OC8-HSL) was released by Anammox granules. The effects of exogenous C8-HSL on the strength, average diameter, and density of Anammox granules were closely related to the operation temperature. When the operation temperature ranged from 11°C to 16°C, the stability of granules could be significantly improved by exogenous C8-HSL. In addition, the addition of C6-HSL and 3OC8-HSL promoted the activity of Anammox granules when the operation temperatures of the reactors were 11-23°C. This study proposed a novel approach to improve the properties of Anammox granules at low temperatures from the perspective of QS. PRACTITIONER POINTS: Endogenous AHLs played an important role in maintaining the activity and stability of Anammox granules at 11-23°C. Exogenous C8-HSL improved the granules stability at the low temperature of 11-16°C. Exogenous C6-HSL or 3OC8-HSL promoted the granules activity at 11-23°C. Supply a novel way to improve the Anammox granules performance at low temperatures.
- Published
- 2021
11. Can high frequency ultrasound combined computed tomography accurately diagnose thyroid tumor?: a protocol of systematic review and meta-analysis
- Author
-
Lin-hua Zhang
- Published
- 2020
- Full Text
- View/download PDF
12. Improving the resistance of Anammox granules to extreme pH shock: The effects of denitrification sludge EPS enhanced by a fluctuating C/N ratio cultivation on granules
- Author
-
Zhaoming Zheng, Kai Zhang, Jia Wei, Jing Zhang, Yongzhen Peng, Jun Li, and Lin-hua Zhang
- Subjects
Flocculation ,Environmental Engineering ,Denitrification ,010504 meteorology & atmospheric sciences ,Homoserine ,chemistry.chemical_element ,Acyl-Butyrolactones ,010501 environmental sciences ,Polysaccharide ,01 natural sciences ,chemistry.chemical_compound ,Bioreactors ,Environmental Chemistry ,Food science ,Waste Management and Disposal ,0105 earth and related environmental sciences ,chemistry.chemical_classification ,Sewage ,Chemistry ,Granule (cell biology) ,Quorum Sensing ,Hydrogen-Ion Concentration ,Pollution ,Nitrogen ,Anammox ,Lactone - Abstract
This study investigated the effects of denitrification sludge EPS enhanced (DS-EPSCN) by a fluctuating carbon and nitrogen ratio (C/N) cultivation strategy on the properties of Anammox granules under extreme acid or alkaline shock. The results showed that the DS-EPSCN significantly improved the nitrogen removal performance of low-density Anammox granular sludge (Granules-L) and high-density Anammox granular sludge (Granules-H) under extreme acid shock (pH 5.0). The contents of high-molecular-weight substances (such as aromatic proteins and polysaccharides) in the DS-EPSCN rose markedly, contributing to a substantial increase in the flocculation efficiency under acidic conditions and increasing the granule stability. In addition, abundant amounts of N-butyryl- dl -homoserine lactone (C4-HSL) and N-hexanoyl- dl -homoserine lactone (C6-HSL) in the DS-EPSCN promoted the granule activity. However, under extreme alkaline shock (pH 10.5), the flocculation efficiency of the DS-EPSCN was poor, and the addition of DS-EPSCN had no influence on the stability of the granules but improved the activity of the Granules-H. The reason was that the release mechanism of the endogenous acyl-homoserine lactone (AHL) signals in the Granules-H was activated by the exogenous C4-HSL and C6-HSL in the DS-EPSCN under alkaline conditions, leading to increased Granules-H activity. This research provides a novel approach to enhance the resistance of Anammox granular sludge to extreme pH shock.
- Published
- 2021
- Full Text
- View/download PDF
13. An effective chirospecific synthesis of (+)-pilocarpine from L-aspartic acid
- Author
-
Dener, Jeffrey M., Lin-Hua Zhang, and Rapoport, Henry
- Subjects
Organic compounds -- Synthesis ,Alkaloids -- Research ,Pilocarpine -- Research ,Aspartate -- Usage ,Ring formation (Chemistry) -- Methods ,Lactones -- Research ,Imidazole -- Research ,Biological sciences ,Chemistry - Abstract
The 10-step chirospecific synthesis of (+)-pilocarpine involves the use of N-protected dimethyl aspartate in an alkylation step that establishes the C-3 stereocenter. Subsequent hydrolysis of the alpha-ester, bromo substitution of the amino group, esterification and a unique lactonization via a Reformatsky process form the imidazole-lactone structure. Hydrogenolysis of the carbonyl and reduction of the monoester give the anti-glaucoma alkaloid in 51% overall yield from L-aspartic acid.
- Published
- 1993
14. Can high-frequency ultrasound combined computed tomography accurately diagnose thyroid tumor?
- Author
-
Lin-Hua Zhang, Wei Tao, and Gang Chen
- Subjects
Research design ,China ,medicine.medical_specialty ,Quality Assurance, Health Care ,thyroid tumor ,MEDLINE ,specificity ,Computed tomography ,Cochrane Library ,Multimodal Imaging ,Sensitivity and Specificity ,03 medical and health sciences ,0302 clinical medicine ,Study Protocol Systematic Review ,Humans ,Medicine ,Medical physics ,Thyroid Neoplasms ,030212 general & internal medicine ,Ultrasonography ,Protocol (science) ,medicine.diagnostic_test ,business.industry ,computed tomography ,General Medicine ,high-frequency ultrasound ,sensitivity ,Research Design ,Case-Control Studies ,030220 oncology & carcinogenesis ,Meta-analysis ,Tomography, X-Ray Computed ,business ,Quality assurance ,Software ,Research Article ,High frequency ultrasound - Abstract
Background: Previous clinical studies have reported that clinical value of high-frequency ultrasound combined computed tomography (HFUCT) is used for diagnosis of thyroid tumor (TT). However, no study has investigated this topic systematically. Therefore, this study will evaluate the clinical value of HFUCT for the diagnosis of TT. Methods: We will search the databases of Cochrane Library, EMBASE, PUBMED, SCOPUS, Web of Science, OpenGrey, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, and China National Knowledge Infrastructure from any time period published to the present. We will consider all case-controlled studies that assessed the clinical value of HFUCT for diagnosis of TT. Two authors will independently scan titles and abstracts to check eligible studies, followed by full-text read. We will extract data and assess study quality using Quality Assessment of Diagnostic Accuracy Studies tool. RevMan 5.3 software will be utilized for data pooling and statistical analysis. Results: This study will be performed to assess the clinical value of HFUCT for the diagnosis of TT, and will provide an evidence-based synthesis for clinical application and further study. Conclusion: Summary of this study will provide the latest evidence to determine whether HFUCT can be used for TT diagnosis accurately. Study registration: INPLASY202040022.
- Published
- 2020
- Full Text
- View/download PDF
15. Secondary neurotransmitter deficiencies in epilepsy caused by voltage-gated sodium channelopathies: A potential treatment target?
- Author
-
Casper Shyr, Lin-Hua Zhang, Margot I. Van Allen, Gabriella Horvath, Simon Pope, J. Helen Cross, Allison Matthews, Natalie Trump, Wyeth W. Wasserman, Michelle Demos, Sylvia Stockler-Ipsiroglu, Colin J. D. Ross, Lilah Toker, Simon Heales, Clara D.M. van Karnebeek, Ogan Mancarci, Simone Race, Paul Pavlidis, and Other departments
- Subjects
Male ,0301 basic medicine ,Drug Resistant Epilepsy ,Dopamine ,Endocrinology, Diabetes and Metabolism ,Pediatrics ,Biochemistry ,Sodium Channels ,Receptors, Dopamine ,Epilepsy ,chemistry.chemical_compound ,Child Development ,0302 clinical medicine ,Endocrinology ,Channelopathy ,Exome ,Child ,Neurotransmitter ,Tetrahydrofolates ,Neurotransmitter Agents ,Brain Diseases ,NAV1.2 Voltage-Gated Sodium Channel ,Homovanillic acid ,Hydroxyindoleacetic Acid ,Hypotonia ,Neurology ,Muscle Hypotonia ,Female ,Cerebellar atrophy ,medicine.symptom ,SCN8A ,Serotonin ,medicine.medical_specialty ,Mutation, Missense ,Neurosurgery ,Neurotransmission ,Biology ,03 medical and health sciences ,Genetic Disorders ,Seizures ,Internal medicine ,Genetics ,medicine ,Humans ,Autistic Disorder ,Molecular Biology ,Nav1.6 ,Nav1.2 ,Infant ,Homovanillic Acid ,Sequence Analysis, DNA ,medicine.disease ,030104 developmental biology ,chemistry ,NAV1.6 Voltage-Gated Sodium Channel ,Channelopathies ,Therapy ,Nervous System Diseases ,SCN2A ,030217 neurology & neurosurgery - Abstract
We describe neurotransmitter abnormalities in two patients with drug-resistant epilepsy resulting from deleterious de novo mutations in sodium channel genes. Whole exome sequencing identified a de novo SCN2A splice-site mutation (c.2379 +1G>A, p.G1u717Gly.fs*30) resulting in deletion of exon 14, in a 10-year old male with early onset global developmental delay, intermittent ataxia, autism, hypotonia, epileptic encephalopathy and cerebral/cerebellar atrophy. In the cerebrospinal fluid both homovanillic acid and 5-hydroxyindoleacetic acid were significantly decreased; extensive biochemical and genetic investigations ruled out primary neurotransmitter deficiencies and other known inborn errors of metabolism. In an 8-year old female with an early onset intractable epileptic encephalopathy, developmental regression, and progressive cerebellar atrophy, a previously unreported de novo missense mutation was identified in SCN8A (c.5615G>A; p.Arg1872GIn), affecting a highly conserved residue located in the C-terminal of the Na(v)1.6 protein. Aside from decreased homovanillic acid and 5-hydroxyindoleacetic acid, 5-methyltetrahydrofolate was also found to be low. We hypothesize that these channelopathies cause abnormal synaptic mono-amine metabolite secretion/uptake via impaired vesicular release and imbalance in electrochemical ion gradients, which in turn aggravate the seizures. Treatment with oral 5-hydroxytryptophan, L-Dopa/Carbidopa, and a dopa agonist resulted in mild improvement of seizure control in the male case, most likely via dopamine and serotonin receptor activated signal transduction and modulation of glutamatergic, GABA-ergic and glycinergic neurotransmission. Neurotransmitter analysis in other sodium channelopathy patients will help validate our findings, potentially yielding novel treatment opportunities. (C) 2015 Elsevier Inc. All rights reserved
- Published
- 2016
- Full Text
- View/download PDF
16. ABCA8 Regulates Cholesterol Efflux and High-Density Lipoprotein Cholesterol Levels
- Author
-
Laia Trigueros-Motos, Ian Tietjen, Fabian Dorninger, Marie-Pierre Dubé, Pradeep Narayanaswamy, Chris Radomski, Alinda W. M. Schimmel, Federico Torta, Geesje M. Dallinga-Thie, Johannes Berger, Chung Hwee Thiam, Michael R. Hayden, Gopala K. Yakala, Amina Barhdadi, Markus R. Wenk, Liang Juin Tan, Julian C. van Capelleveen, Veronique Angeli, Martin H. Kang, Uwe J. F. Tietge, Lidiya G. Dimova, Roshni R. Singaraja, David Castano, Lin-Hua Zhang, Daniel Heqing Wu, G. Kees Hovingh, Ee Chu Chai, Center for Liver, Digestive and Metabolic Diseases (CLDM), Lifestyle Medicine (LM), Other departments, ACS - Amsterdam Cardiovascular Sciences, Experimental Vascular Medicine, Vascular Medicine, AGEM - Amsterdam Gastroenterology Endocrinology Metabolism, ACS - Diabetes & metabolism, and ACS - Atherosclerosis & ischemic syndromes
- Subjects
0301 basic medicine ,Male ,Heredity ,DNA Mutational Analysis ,ATHEROGENESIS ,030204 cardiovascular system & hematology ,ABCA8 ,TRANSPORT IN-VIVO ,Cholesterol, Dietary ,chemistry.chemical_compound ,Feces ,0302 clinical medicine ,High-density lipoprotein ,HDL-CHOLESTEROL ,Chlorocebus aethiops ,Mice, Knockout ,PLASMA ,Reverse cholesterol transport ,Transfection ,Middle Aged ,Pedigree ,DEFICIENCY ,Phenotype ,Biochemistry ,Liver ,Apolipoprotein B-100 ,COS Cells ,Female ,Efflux ,Cardiology and Cardiovascular Medicine ,Adult ,medicine.medical_specialty ,Heterozygote ,HDL ,Biology ,Diet, High-Fat ,03 medical and health sciences ,Internal medicine ,medicine ,Animals ,Humans ,Aged ,Apolipoprotein A-I ,Cholesterol ,MUTATIONS ,Macrophages ,HEK 293 cells ,Cholesterol, HDL ,cholesterol ,Heterozygote advantage ,Biological Transport ,reverse cholesterol transport ,Mice, Inbred C57BL ,MICE ,030104 developmental biology ,Endocrinology ,HEK293 Cells ,chemistry ,ATHEROSCLEROSIS ,Case-Control Studies ,Mutation ,ATP-Binding Cassette Transporters ,Biomarkers - Abstract
Objective— High-density lipoproteins (HDL) are considered to protect against atherosclerosis in part by facilitating the removal of cholesterol from peripheral tissues. However, factors regulating lipid efflux are incompletely understood. We previously identified a variant in adenosine triphosphate–binding cassette transporter A8 ( ABCA8 ) in an individual with low HDL cholesterol (HDLc). Here, we investigate the role of ABCA8 in cholesterol efflux and in regulating HDLc levels. Approach and Results— We sequenced ABCA8 in individuals with low and high HDLc and identified, exclusively in low HDLc probands, 3 predicted deleterious heterozygous ABCA8 mutations (p.Pro609Arg [P609R], IVS17-2 A>G and p.Thr741Stop [T741X]). HDLc levels were lower in heterozygous mutation carriers compared with first-degree family controls (0.86±0.34 versus 1.17±0.26 mmol/L; P =0.005). HDLc levels were significantly decreased by 29% ( P =0.01) in Abca8b −/− mice on a high-cholesterol diet compared with wild-type mice, whereas hepatic overexpression of human ABCA8 in mice resulted in significant increases in plasma HDLc and the first steps of macrophage-to-feces reverse cholesterol transport. Overexpression of wild-type but not mutant ABCA8 resulted in a significant increase (1.8-fold; P =0.01) of cholesterol efflux to apolipoprotein AI in vitro. ABCA8 colocalizes and interacts with adenosine triphosphate–binding cassette transporter A1 and further potentiates adenosine triphosphate–binding cassette transporter A1–mediated cholesterol efflux. Conclusions— ABCA8 facilitates cholesterol efflux and modulates HDLc levels in humans and mice.
- Published
- 2017
17. Thermogravimetric and Pyrolysis Kinetic Analysis of Elmwood
- Author
-
Guo Kai Zhang, Lin Hua Zhang, Yong Zhang Cui, Peng Gao, and Ming Tian Tang
- Subjects
Arrhenius equation ,symbols.namesake ,Thermogravimetric analysis ,Chemistry ,Scientific method ,Kinetic analysis ,General Engineering ,symbols ,Analytical chemistry ,Biomass ,Activation energy ,Atmospheric temperature range ,Pyrolysis - Abstract
Thermal gravimetric analysis is an important method in the study of biomass. In this paper, using this method on elmwood, through pyrolysis experimental analysis at different heating rates (10,30,50,80 °C / min), get the TG-DTG curves to investigate the pyrolysis characteristics of elmwood. The results show that the pyrolysis process of Elmwood are divided into three stages; With the increasing of heating rate, the major pyrolysis temperature range expansion, the temperature corresponding maximum weight loss rate rose; while taking advantage of Lyon integration algorithm for solving the activation energy of 78.47-271.58kj/mol. indicating Arrhenius first-order single-step reaction with biomass pyrolysis reaction has good linearity.
- Published
- 2014
- Full Text
- View/download PDF
18. Simulation Investigation on Structural Parameter of Hot Air Igniter of Biomass
- Author
-
Peng Gao, Lin Hua Zhang, Ming Tian Tang, Yong Zhang Cui, and Guo Kai Zhang
- Subjects
Materials science ,Waste management ,Airflow ,Pellets ,Autoignition temperature ,General Medicine ,Mechanics ,Heat transfer coefficient ,law.invention ,Ignition system ,Physics::Plasma Physics ,law ,Total air temperature ,Electric heating ,Constant air volume ,Physics::Atmospheric and Oceanic Physics - Abstract
In view of rich resources of corn stalks, cotton stalks forming pellets hot ignition performance, using CFD numerical simulation analysis to study the key parameters of electric ignition such as the surface ignition temperature, air velocity, air flow distribution ratio of influence of hot air outlet temperature. Obtained that increasing electric heating surface temperature, reducing the air flow velocity and convective heat transfer coefficient of the outer tube can significantly improve the ignition temperature of the outlet hot air, the outlet hot air temperature should be higher than 450 °C. Ignition internal and external air passage area ratio affects the allocation of hot air flow, the best area ratio of between 1.8-2.2.
- Published
- 2014
- Full Text
- View/download PDF
19. The Application of Genetic Algorithm on the Regulation of Central Heating System
- Author
-
Ling Liu, Dong Yang, Lin Hua Zhang, and Ting Ting Chen
- Subjects
Mathematical optimization ,Engineering ,business.industry ,Flow (psychology) ,Flux ,General Medicine ,Operational optimization ,Heating system ,Water temperature ,Genetic algorithm ,Operational costs ,Process engineering ,business ,User needs - Abstract
For the operational optimization problem of supply temperature and flow adjustment (known as “quality-quantity” regulation) in district heating system.To meet user needs hot,an operational cost equation of primary network is set up, taking the supply water temperature and the water flux as variables. The optimization objective of this equation is to minimize operational cost.Based on the genetic algorithm,and finally get the optimal water temperature and water flux. Analysis the several regulation of supply water temperature and water flux, finally proposed heating system integrated regulation.
- Published
- 2014
- Full Text
- View/download PDF
20. The Optimization Analysis of Hydraulic Junction Location of Three-Sources Branched Heat-Supply Network
- Author
-
Shou Jun Zhou, Ling Liu, Lin Hua Zhang, Ting Ting Chen, and Dong Yang
- Subjects
Consumption (economics) ,Mathematical optimization ,Engineering ,Heating system ,business.industry ,Heat supply ,General Medicine ,Electric power ,Energy consumption ,State (computer science) ,business ,Automotive engineering - Abstract
In this paper, we shall first briefly introduce the hydraulic junction of three-sources branched heat-supply network and the related optimization method. It's difficult to guarantee that the system runs in optimal state and it increases energy consumption in the system. In view of this situation this paper proposes a method to find the optimal positions of hydraulic intersections based on analyzing a real heating system with three heat sources in Jining. The optimization objective is to minimize the electric power consumption of circulating water pumps in district heating system. Finally, optimization programs are designed and the optimized results verify the feasibility and validity of the method compared with conventional experience values.
- Published
- 2014
- Full Text
- View/download PDF
21. The Research of Heat Loss Calculation Model of Directly-Buried Heating Pipe
- Author
-
Ting Ting Chen, Dong Yang, Lin Hua Zhang, and Ling Liu
- Subjects
Water heating ,Engineering ,Polynomial ,business.industry ,Pipeline (computing) ,Thermal resistance ,Heat losses ,Thermodynamics ,General Medicine ,Mechanics ,Thermal ,business ,Linear equation ,Variable (mathematics) - Abstract
In this paper, we shall discuss the calculate method of heat loss of central heating pipes.the calculation formulas available are too complicated and inconvenienced to analysis the dynamic thermal conditions of heating pipeline. Therefore, this paper presents one order polynomial with least-squares solution, and then establishes linear equations of heating pipeline heat loss that the hot water temperature as a variable alone. It is based on the comparision and analysis of buried hot water heating pipeline heat loss formula. This method will simplify not only the calculation, but also the model of calculation analysis for different diameter, different insulation materials. The result is that the deviation of the formula is caused mainly by the thermal resistance. The relative errors of simplified formula and the selection formulas are less than 3%, which can meet the requirements for engineering applications.
- Published
- 2014
- Full Text
- View/download PDF
22. Large Dairy Farms Biogas Energy Environment Engineering Technology Research
- Author
-
Xue Ting Liu, Dong Yang, Lin Hua Zhang, and Meng Zhang
- Subjects
Waste gas ,Engineering ,Waste management ,Biogas ,business.industry ,Technology research ,Process (engineering) ,General Engineering ,business ,Biogas production - Abstract
In this paper, according to the domestic large dairy farms waste gas energy environment engineering technology research, forecasts the market application prospect of biogas technology, and analyzes the two kinds of biogas engineering technology characteristics and how to correctly choose the biogas production process.
- Published
- 2014
- Full Text
- View/download PDF
23. Novel homozygous PCK1 mutation causing cytosolic phosphoenolpyruvate carboxykinase deficiency presenting as childhood hypoglycemia, an abnormal pattern of urine metabolites and liver dysfunction
- Author
-
Jukka S. Moilanen, Allison Matthews, Lin-Hua Zhang, Riikka Keski-Filppula, Johanna Uusimaa, Matti Nuutinen, Päivi Myllynen, Jessie M. Cameron, Saikat Santra, Arndt Rolfs, Päivi Vieira, Elisa Rahikkala, Richard J. Rodenburg, Clara D.M. van Karnebeek, AGEM - Amsterdam Gastroenterology Endocrinology Metabolism, ANS - Cellular & Molecular Mechanisms, and Paediatric Metabolic Diseases
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Recurrent hypoglycemia ,Mutation, Missense ,Urine ,Biology ,Hypoglycemia ,Biochemistry ,03 medical and health sciences ,Endocrinology ,PCK1 ,Internal medicine ,Chlorocebus aethiops ,Genetics ,medicine ,Animals ,Humans ,Exome ,Genetic Predisposition to Disease ,Child ,Molecular Biology ,Liver Diseases ,Homozygote ,Intracellular Signaling Peptides and Proteins ,Metabolic Disorders Radboud Institute for Molecular Life Sciences [Radboudumc 6] ,Sequence Analysis, DNA ,medicine.disease ,Pedigree ,3. Good health ,Pyruvate carboxylase ,Citric acid cycle ,030104 developmental biology ,Liver ,Alanine transaminase ,COS Cells ,biology.protein ,Female ,Phosphoenolpyruvate Carboxykinase (GTP) ,Phosphoenolpyruvate carboxykinase ,Carbohydrate Metabolism, Inborn Errors ,Urine organic acids - Abstract
Clinical and laboratory data were collected from three Finnish patients including a sibling pair and another unrelated child with unexplained childhood hypoglycemia. Transient elevation of alanine transaminase, lactate and tricarboxylic acid cycle intermediates, especially fumarate, were noticed in urine organic acid analysis. Exome sequencing was performed for the patients and their parents. A novel homozygous PCK1 c.925G>A (p.G309R) mutation was detected in all affected individuals. COS-1 cells transfected with mutant PCK1 transcripts were used to study the pathogenic nature of the detected variant. The COS-1 transfected cells showed the mutant gene to be incapable of producing a normally functioning cytosolic phosphoenolpyruvate carboxykinase (PEPCK) enzyme. This report further delineates the clinical phenotype of isolated cytosolic PEPCK deficiency and offers a metabolic pattern helping to recognize these patients. Cytosolic PEPCK deficiency should be considered in the differential diagnosis of children presenting with hypoglycemia, hepatic dysfunction and elevated tricarboxylic acid intermediates in urinary organic acid analysis.
- Published
- 2017
24. Unravelling 5-oxoprolinuria (pyroglutamic aciduria) due to bi-allelic OPLAH mutations: 20 new mutations in 14 families
- Author
-
Aynur Damli-Huber, Ivailo Tournev, Hilary Vallance, Bjørn Magne Jåtun, Markus Rauchenzauner, Sema Kalkan Uçar, Jörn Oliver Sass, Daniel Beumer, Albena Jordanova, Majid Alfadhel, Karmen Bilić, Clara D.M. van Karnebeek, Maja Tarailo-Graovac, Mahmut Çoker, Claudia Till, Fowzan S. Alkuraya, Ivo Barić, Nuria Garcia Segarra, Michael T. Geraghty, Corinne Gemperle-Britschgi, Bryan Sayson, Melanie Walter, Lin-Hua Zhang, Nisha Patel, Cynthia Xin Ye, Eissa Faqeih, Merten Kriewitz, University of Zurich, Sass, Jörn Oliver, and Other departments
- Subjects
Male ,Pyroglutamate Hydrolase ,0301 basic medicine ,Hemolytic anemia ,Heterozygote ,1303 Biochemistry ,Adolescent ,Endocrinology, Diabetes and Metabolism ,610 Medicine & health ,Biology ,medicine.disease_cause ,Biochemistry ,Glutathione Synthase ,03 medical and health sciences ,Endocrinology ,1311 Genetics ,Genotype ,Genetics ,medicine ,1312 Molecular Biology ,Humans ,Allele ,Child ,Amino Acid Metabolism, Inborn Errors ,Molecular Biology ,Alleles ,Mutation ,Homozygote ,Infant ,Heterozygote advantage ,medicine.disease ,Glutathione synthetase deficiency ,Glutathione ,Glutathione synthetase ,Pyrrolidonecarboxylic Acid ,1310 Endocrinology ,2712 Endocrinology, Diabetes and Metabolism ,030104 developmental biology ,Inborn error of metabolism ,10036 Medical Clinic ,Child, Preschool ,Female ,Human medicine - Abstract
Primary 5-oxoprolinuria (pyroglutamic aciduria) is caused by a genetic defect in the gamma-glutamyl cycle, affecting either glutathione synthetase or 5-oxoprolinase. While several dozens of patients with glutathione synthetase deficiency have been reported, with hemolytic anemia representing the clinical key feature, 5-oxoprolinase deficiency due to OPLAH mutations is less frequent and so far has not attracted much attention. This has prompted us to investigate the clinical phenotype as well as the underlying genotype in patients from 14 families of various ethnic backgrounds who underwent diagnostic mutation analysis following the detection of 5-oxoprolinuria. In all patients with 5-oxoprolinuria studied, bi-allelic mutations in OPLAH were indicated. An autosomal recessive mode of inheritance for 5-oxoprolinase deficiency is further supported by the identification of a single mutation in all 9/14 parent sample sets investigated (except for the father of one patient whose result suggests homozygosity), and the absence of 5-oxoprolinuria in all tested heterozygotes. It is remarkable, that all 20 mutations identified were novel and private to the respective families. Clinical features were highly variable and in several sib pairs, did not segregate with 5-oxoprolinuria. Although a pathogenic role of 5-oxoprolinase deficiency remains possible, this is not supported by our findings. Additional patient ascertainment and long-term follow-up is needed to establish the benign nature of this inborn error of metabolism. It is important that all symptomatic patients with persistently elevated levels of 5-oxoproline and no obvious explanation are investigated for the genetic etiology. (C) 2016 Elsevier Inc. All rights reserved.
- Published
- 2016
- Full Text
- View/download PDF
25. Exome Sequencing and the Management of Neurometabolic Disorders
- Author
-
David S. Wishart, Bojana Rakic, Casper Shyr, Rupasri Mandal, Maja Tarailo-Graovac, Andre Mattman, Cristina Skrypnyk, Patrice Eydoux, Paul Shekel, Majid Alfadhel, Stuart E. Turvey, Janis M. Dionne, Hilary Vallance, Michelle Demos, A. Mark Evans, Colin J. D. Ross, Anna Lehman, Matthias R. Baumgartner, Jacob Rozmus, Bryan Sayson, Jan M. Friedman, Margaret L. McKinnon, Andrea Superti-Furga, Leo A. J. Kluijtmans, Britt I. Drögemöller, Kathryn Selby, Mary B. Connolly, Gabriella Horvath, Daniel Metzger, Kirk R. Schultz, John K. Wu, Ian Garber, Linlea Armstrong, Jessie M. Cameron, Ramona Salvarinova, Clara D.M. van Karnebeek, Dimitrios I. Zafeiriou, Jiqiang Ling, Ron A. Wevers, Lin Hua Zhang, Jiang Wu, Oluseye A. Ogunbayo, Graham Sinclair, Sylvia Stockler-Ipsiroglu, Suzanne M E Lewis, Margot I. Van Allen, Jessica J. Y. Lee, Wyeth W. Wasserman, Mena Abdelsayed, Peter C. Ruben, Patricie Burda, Aspasia Michoulas, Sandra Sirrs, Saikat Santra, Xin C. Ye, Tammie Dewan, Amit P. Bhavsar, and Other departments
- Subjects
0301 basic medicine ,Proband ,Adult ,Male ,Adolescent ,Genotype ,Other Research Radboud Institute for Molecular Life Sciences [Radboudumc 0] ,Bioinformatics ,03 medical and health sciences ,Young Adult ,Intellectual Disability ,Intellectual disability ,Medicine ,Humans ,Exome ,Genetic Testing ,Child ,Exome sequencing ,Genetic testing ,Genetics ,medicine.diagnostic_test ,business.industry ,Infant ,General Medicine ,Sequence Analysis, DNA ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,medicine.disease ,Phenotype ,Developmental disorder ,030104 developmental biology ,Child, Preschool ,Female ,business ,Metabolism, Inborn Errors - Abstract
BACKGROUND: Whole-exome sequencing has transformed gene discovery and diagnosis in rare diseases. Translation into disease-modifying treatments is challenging, particularly for intellectual developmental disorder. However, the exception is inborn errors of metabolism, since many of these disorders are responsive to therapy that targets pathophysiological features at the molecular or cellular level.METHODS: To uncover the genetic basis of potentially treatable inborn errors of metabolism, we combined deep clinical phenotyping (the comprehensive characterization of the discrete components of a patient's clinical and biochemical phenotype) with whole-exome sequencing analysis through a semiautomated bioinformatics pipeline in consecutively enrolled patients with intellectual developmental disorder and unexplained metabolic phenotypes.RESULTS: We performed whole-exome sequencing on samples obtained from 47 probands. Of these patients, 6 were excluded, including 1 who withdrew from the study. The remaining 41 probands had been born to predominantly nonconsanguineous parents of European descent. In 37 probands, we identified variants in 2 genes newly implicated in disease, 9 candidate genes, 22 known genes with newly identified phenotypes, and 9 genes with expected phenotypes; in most of the genes, the variants were classified as either pathogenic or probably pathogenic. Complex phenotypes of patients in five families were explained by coexisting monogenic conditions. We obtained a diagnosis in 28 of 41 probands (68%) who were evaluated. A test of a targeted intervention was performed in 18 patients (44%).CONCLUSIONS: Deep phenotyping and whole-exome sequencing in 41 probands with intellectual developmental disorder and unexplained metabolic abnormalities led to a diagnosis in 68%, the identification of 11 candidate genes newly implicated in neurometabolic disease, and a change in treatment beyond genetic counseling in 44%. (Funded by BC Children's Hospital Foundation and others.).
- Published
- 2016
- Full Text
- View/download PDF
26. Niacin increases HDL biogenesis by enhancing DR4-dependent transcription of ABCA1 and lipidation of apolipoprotein A-I in HepG2 cells
- Author
-
Vaijinath S. Kamanna, Xi-Ming Xiong, Shobha H. Ganji, Moti L. Kashyap, and Lin-Hua Zhang
- Subjects
medicine.medical_specialty ,Transcription, Genetic ,Apolipoprotein B ,human hepatoblstoma cell line ,Movement ,apolipoprotein A-I ,ATP binding cassette transporterA1 ,QD415-436 ,High-Density Lipoproteins, Pre-beta ,Niacin ,Biochemistry ,chemistry.chemical_compound ,Endocrinology ,Internal medicine ,Gene expression ,ABCA1 Gene ,medicine ,polycyclic compounds ,direct repeat 4 ,Humans ,Phospholipids ,Research Articles ,Repetitive Sequences, Nucleic Acid ,Regulation of gene expression ,biology ,Cholesterol ,Cholesterol, HDL ,digestive, oral, and skin physiology ,HDL biogenesis ,Liver X receptor alpha ,food and beverages ,nutritional and metabolic diseases ,Biological Transport ,Hep G2 Cells ,Cell Biology ,Culture Media ,Gene Expression Regulation ,chemistry ,ABCA1 ,biology.protein ,ATP-Binding Cassette Transporters ,lipids (amino acids, peptides, and proteins) ,high density lipoproteins ,ATP Binding Cassette Transporter 1 - Abstract
The lipidation of apoA-I in liver greatly influences HDL biogenesis and plasma HDL levels by stabilizing the secreted apoA-I. Niacin is the most effective lipid-regulating agent clinically available to raise HDL. This study was undertaken to identify regulatory mechanisms of niacin action in hepatic lipidation of apoA-I, a critical event involved in HDL biogenesis. In cultured human hepatocytes (HepG2), niacin increased: association of apoA-I with phospholipids and cholesterol by 46% and 23% respectively, formation of lipid-poor single apoA-I molecule-containing particles up to ∼ 2.4-fold, and pre β 1 and α migrating HDL particles. Niacin dose-dependently stimulated the cell efflux of phospholipid and cholesterol and increased transcription of ABCA1 gene and ABCA1 protein. Mutated DR4, a binding site for nuclear factor liver X receptor alpha (LXR α ) in the ABCA1 promoter, abolished niacin stimulatory effect. Further, knocking down LXR α or ABCA1 by RNA interference eliminated niacin-stimulated apoA-I lipidation. Niacin treatment did not change apoA-I gene expression. The present data indicate that niacin increases apoA-I lipidation by enhancing lipid efflux through a DR4-dependent transcription of ABCA1 gene in HepG2 cells. A stimulatory role of niacin in early hepatic formation of HDL particles suggests a new mechanism that contributes to niacin action to increase the stability of newly synthesized circulating HDL.
- Published
- 2012
27. miR-33a Modulates ABCA1 Expression, Cholesterol Accumulation, and Insulin Secretion in Pancreatic Islets
- Author
-
C. Bruce Verchere, Thomas Abraham, Michael R. Hayden, Nadeeja Wijesekara, Lin Hua Zhang, Martin H. Kang, Alpana Bhattacharjee, and Garth L. Warnock
- Subjects
Apolipoprotein E ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Biology ,Islets of Langerhans ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Internal medicine ,Insulin Secretion ,polycyclic compounds ,Internal Medicine ,medicine ,Animals ,Humans ,Insulin ,Secretion ,030304 developmental biology ,0303 health sciences ,geography ,geography.geographical_feature_category ,Pancreatic islets ,beta-Cyclodextrins ,Islet ,Insulin oscillation ,MicroRNAs ,Cholesterol ,Glucose ,Endocrinology ,medicine.anatomical_structure ,Islet Studies ,030220 oncology & carcinogenesis ,ABCA1 ,biology.protein ,ATP-Binding Cassette Transporters ,lipids (amino acids, peptides, and proteins) ,ATP Binding Cassette Transporter 1 - Abstract
Changes in cellular cholesterol affect insulin secretion, and β-cell–specific deletion or loss-of-function mutations in the cholesterol efflux transporter ATP-binding cassette transporter A1 (ABCA1) result in impaired glucose tolerance and β-cell dysfunction. Upregulation of ABCA1 expression may therefore be beneficial for the maintenance of normal islet function in diabetes. Studies suggest that microRNA-33a (miR-33a) expression inversely correlates with ABCA1 expression in hepatocytes and macrophages. We examined whether miR-33a regulates ABCA1 expression in pancreatic islets, thereby affecting cholesterol accumulation and insulin secretion. Adenoviral miR-33a overexpression in human or mouse islets reduced ABCA1 expression, decreased glucose-stimulated insulin secretion, and increased cholesterol levels. The miR-33a–induced reduction in insulin secretion was rescued by cholesterol depletion by methyl-β-cyclodextrin or mevastatin. Inhibition of miR-33a expression in apolipoprotein E knockout islets and ABCA1 overexpression in β-cell–specific ABCA1 knockout islets rescued normal insulin secretion and reduced islet cholesterol. These findings confirm the critical role of β-cell ABCA1 in islet cholesterol homeostasis and β-cell function and highlight modulation of β-cell miR-33a expression as a means to influence insulin secretion.
- Published
- 2012
- Full Text
- View/download PDF
28. The Influence of Industry Analysis Value to Combustion Characteristics for Pellet Fuel
- Author
-
Lin Hua Zhang, Yun Xia Qu, Yong Zhang Cui, Min Na Ren, and Xiao Li
- Subjects
Materials science ,Waste management ,Pellet ,Pellet fuel ,General Engineering ,Biomass ,Autoignition temperature ,Coke ,Combustion ,Pulp and paper industry ,Environmentally friendly ,Husk - Abstract
The biomass pellet fuel has the advantages of easily to be stored and transported,convenie -ntly to be used,clean and environmental friendly as well as high combustion efficiency. On the fou -ndation of studying combustion process, this paper obtained the industry analysis values of eight kinds of biomass pellet fuels by experiment. Combined with fire indicator of Fu-Zhang and combus -tion characteristics indicator of Yan Niu, the values of FZ and ZM are calculated, and then it is obtained that the decorative paper has the minimum ignition temperature, contrary the rice husk has the highest ignition temperature. Finally, by observing the morphology of ash after the burning of fuel combustion, it is pointed out that with increasing temperature from 740°C to 920°C, gray color of pell -et fuel gradually from black to white, hardness gra -dually hardened by the soft, even coke residue.
- Published
- 2012
- Full Text
- View/download PDF
29. Metabolic Flux Analysis and Optimal Control in the Process of Ectoine Fermentation
- Author
-
Lin Hua Zhang, Xin Zheng, and Ya Jun Lang
- Subjects
biology ,Monosodium glutamate ,General Engineering ,Metabolic network ,Ectoine ,biology.organism_classification ,Halomonas venusta ,chemistry.chemical_compound ,Biochemistry ,chemistry ,Metabolic flux analysis ,Yield (chemistry) ,Fermentation ,Food science ,Flux (metabolism) - Abstract
In this study, the metabolic network of ectoine by Halomonas venusta DSM 4743 was established. The key nodes to influence the ectoine fermentation in metabolic flux and the basis during optimal control of fermentation process were investigated. The results showed that G6P, α-KG and OAA nodes were the key factors to influence the synthesis of ectoine. The metabolic flux distributions at the key nodes were significantly improved and ectoine concentration was enhanced in ectoine fermentation by adopting monosodium glutamate as the sole carbon and nitrogen sources, feeding monosodium glutamate and supplying oxygen limitedly. The batch fermentation was carried out in 10 L fermentor , the concentration and yield of ectoine was 8.4 g/L and 0.1 g/g, respectively, which were increased by 2.8 and 2 times, by comparison with batch fermentation using glucose as carbon source.
- Published
- 2011
- Full Text
- View/download PDF
30. The Influence of Natural Ventilation to the Thermal and Moisture Environment in a Passive Greenhouse
- Author
-
Li Na Chang and Lin Hua Zhang
- Subjects
Moisture ,Meteorology ,business.industry ,Thermal ,Airflow ,General Engineering ,Humidity ,Environmental science ,Greenhouse ,Natural ventilation ,Computational fluid dynamics ,business ,Degree (temperature) - Abstract
The temperature and humidity profiles in spatial and temporal field inside the greenhouse are coupled to outside climates. Took a typical soil-walled passive greenhouse located in Jinan, Shandong, China as an example, an unsteady tri-dimensional numerical simulation was applied to solve the temperature and humidity profiles under natural ventilation conditions inside the greenhouse, based on the CFD program. The measurement was carried out to validate the CFD model, the results showed that the special temperature and humidity gradient were obvious inside the greenhouse, a homogeneous temperature and humidity field was obtained at crop level. The simulation results agree well with test values about the temperature and humidity inside the greenhouse with fitting degree of 99.8% and 99.7%, respectively. With high reliability, the model can be used as the basis to predict and control the environment inside the greenhouse. Greenhouse with natural ventilation under different wind conditions was simulated on a typical sunny day to predict the distribution of air flow, temperature and humidity field. By analyzing, some useful conclusions which can provide certain basis about the influence of natural ventilation on the thermal and moisture environment are deduced.
- Published
- 2011
- Full Text
- View/download PDF
31. On Public-Key Encryption Scheme Based on Chebyshev Maps
- Author
-
Wan Yu Duan, Xiu Li Mao, and Lin Hua Zhang
- Subjects
Scheme (programming language) ,Equioscillation theorem ,Chebyshev polynomials ,Discretization ,business.industry ,General Engineering ,Chebyshev filter ,Algebra ,Public-key cryptography ,ComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATION ,Chebyshev pseudospectral method ,Chebyshev nodes ,business ,Algorithm ,computer ,Computer Science::Cryptography and Security ,computer.programming_language ,Mathematics - Abstract
Due to the exceptionally desirable properties, Chebyshev polynomials have been recently proposed for designing public key cryptosystems. However, some proposed schemes were pointed out to be insecure and unpractical. In this paper, we analyze their defects, discretize the Chebyshev maps, generalize properties of Chebyshev polynomials and design an improved scheme. Theoretical analysis shows that it possesses higher security than RSA and experimental results shows it can be implemented easily.
- Published
- 2011
- Full Text
- View/download PDF
32. Niacin inhibits vascular oxidative stress, redox-sensitive genes, and monocyte adhesion to human aortic endothelial cells
- Author
-
Vaijinath S. Kamanna, Lin-Hua Zhang, Moti L. Kashyap, Shobha H. Ganji, and Shucun Qin
- Subjects
Endothelium ,Vasodilator Agents ,Vascular Cell Adhesion Molecule-1 ,Pharmacology ,Biology ,medicine.disease_cause ,Niacin ,Monocytes ,chemistry.chemical_compound ,Cell Adhesion ,medicine ,Humans ,VCAM-1 ,Aorta ,Cells, Cultured ,Monocyte ,Endothelial Cells ,Glutathione ,Angiotensin II ,Lipoproteins, LDL ,Oxidative Stress ,medicine.anatomical_structure ,chemistry ,Biochemistry ,Low-density lipoprotein ,Endothelium, Vascular ,Reactive Oxygen Species ,Cardiology and Cardiovascular Medicine ,Oxidation-Reduction ,Nicotinamide adenine dinucleotide phosphate ,Oxidative stress - Abstract
In pharmacological doses, nicotinic acid (niacin) reduces myocardial infarction, stroke and atherosclerosis. The beneficial effects of niacin on lipoproteins are thought to mediate these effects. We hypothesized that niacin inhibits oxidative stress and redox-sensitive inflammatory genes that play a critical role in early atherogenesis. In cultured human aortic endothelial cells (HAEC), niacin increased nicotinamide adenine dinucleotide phosphate (NAD(P)H) levels by 54% and reduced glutathione (GSH) by 98%. Niacin inhibited: (a) angiotensin II (ANG II)-induced reactive oxygen species (ROS) production by 24-86%, (b) low density lipoprotein (LDL) oxidation by 60%, (c) tumor necrosis factor alpha (TNF-alpha)-induced NF-kappaB activation by 46%, vascular cell adhesion molecule-1 (VCAM-1) by 77-93%, monocyte chemotactic protein-1 (MCP-1) secretion by 34-124%, and (d) in a functional assay TNF-alpha-induced monocyte adhesion to HAEC (41-54%). These findings indicate for the first time that niacin inhibits vascular inflammation by decreasing endothelial ROS production and subsequent LDL oxidation and inflammatory cytokine production, key events involved in atherogenesis. Initial data presented herein support the novel concept that niacin has vascular anti-inflammatory and potentially anti-atherosclerotic properties independent of its effects on lipid regulation.
- Published
- 2009
- Full Text
- View/download PDF
33. Niacin inhibits surface expression of ATP synthase β chain in HepG2 cells: implications for raising HDL
- Author
-
Moti L. Kashyap, Lin-Hua Zhang, Vaijinath S. Kamanna, and Michael C. Zhang
- Subjects
medicine.medical_specialty ,Apolipoprotein B ,Metabolite ,Cell ,QD415-436 ,Endocytosis ,Niacin ,Biochemistry ,Cell Line ,chemistry.chemical_compound ,Endocrinology ,Internal medicine ,medicine ,Humans ,nicotinic acid ,Receptor ,DNA Primers ,Microscopy, Confocal ,ATP synthase ,biology ,Nicotinamide ,Base Sequence ,Reverse Transcriptase Polymerase Chain Reaction ,flow cytometry ,digestive, oral, and skin physiology ,HDL receptor ,food and beverages ,nutritional and metabolic diseases ,Cell Biology ,ATP Synthetase Complexes ,medicine.anatomical_structure ,chemistry ,biology.protein ,lipids (amino acids, peptides, and proteins) ,hepatocytes ,Lipoproteins, HDL - Abstract
Niacin is an effective agent for raising HDL, but its cellular target sites are largely unknown. We examined effects of niacin on the surface expression of ATP synthase beta chain, a newly described HDL/apolipoprotein A-I (apoA-I) receptor for HDL endocytosis, in HepG2 cells. A significant amount of immunodetectable beta chain was observed on the surface of HepG2 cells, which was competitively displaced by apoA-I. Niacin treatment reduced the surface expression of beta chain in HepG2 cells by approximately 27%, and decreased (125)I-labeled HDL uptake up to approximately 35%. However, nicotinamide, a niacin metabolite that does not have clinical lipid effects, exhibited weaker inhibition on the beta chain cell surface expression, and failed to show inhibitory action on (125)I-labeled HDL uptake. Furthermore, anti-beta chain antibody significantly reduced (125)I-labeled HDL uptake and abolished the inhibitory effect of niacin. Niacin did not change beta chain mRNA expression. These data suggest that niacin inhibits cell surface expression of the ATP synthase beta chain, leading to reduced hepatic removal of HDL protein, thus implicating a potential cellular target for niacin action to raise HDL.
- Published
- 2008
34. Loss-of-function mutations in SCN4A cause severe foetal hypokinesia or 'classical' congenital myopathy
- Author
-
Michael G. Hanna, Andreas Slørdahl, Ulla Werlauff, Christian Krarup, Hilary Vallance, Michael T. Gabbett, Francesco Muntoni, Lin Hua Zhang, Emma Matthews, Mark R. Davis, Louise Hartley, Magnhild Rasmussen, Emily C. Oates, Eveline Blom, Roope Männikkö, Caroline Sewry, Lucy Feng, Xin Cynthia Ye, Nigel G. Laing, Clara D.M. van Karnebeek, Glenda Hendson, Hanne Halvorsen, Maria Sframeli, Mena Abdelsayed, Suzanne M E Lewis, Peter C. Ruben, Anna Sarkozy, Michael G. Thor, Nanna Witting, John Vissing, Rahul Phadke, Irina Zaharieva, Gianina Ravenscroft, Jennifer E. Morgan, Martin Ballegaard, Nicoline Løkken, L. D'Argenzio, Erik-Jan Kamsteeg, K. Suetterlin, Matthew Pitt, Paediatric Pulmonology, Paediatric Metabolic Diseases, and Amsterdam Neuroscience - Cellular & Molecular Mechanisms
- Subjects
0301 basic medicine ,Pathology ,medicine.medical_specialty ,Familial periodic paralysis ,Muscle disorder ,Sensory disorders Donders Center for Medical Neuroscience [Radboudumc 12] ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Foetal akinesia ,Congenital myopathy ,Muscle biopsy ,medicine.diagnostic_test ,business.industry ,Skeletal muscle ,Muscle weakness ,Foetal hypokinesia ,Periodic paralysis ,Loss-of-function mutation ,medicine.disease ,Hypotonia ,3. Good health ,030104 developmental biology ,medicine.anatomical_structure ,Neurology (clinical) ,medicine.symptom ,business ,SCN4A ,030217 neurology & neurosurgery - Abstract
Contains fulltext : 167925.pdf (Publisher’s version ) (Open Access) See Cannon (doi:10.1093/brain/awv400) for a scientific commentary on this article.Congenital myopathies are a clinically and genetically heterogeneous group of muscle disorders characterized by congenital or early-onset hypotonia and muscle weakness, and specific pathological features on muscle biopsy. The phenotype ranges from foetal akinesia resulting in in utero or neonatal mortality, to milder disorders that are not life-limiting. Over the past decade, more than 20 new congenital myopathy genes have been identified. Most encode proteins involved in muscle contraction; however, mutations in ion channel-encoding genes are increasingly being recognized as a cause of this group of disorders. SCN4A encodes the alpha-subunit of the skeletal muscle voltage-gated sodium channel (Nav1.4). This channel is essential for the generation and propagation of the muscle action potential crucial to muscle contraction. Dominant SCN4A gain-of-function mutations are a well-established cause of myotonia and periodic paralysis. Using whole exome sequencing, we identified homozygous or compound heterozygous SCN4A mutations in a cohort of 11 individuals from six unrelated kindreds with congenital myopathy. Affected members developed in utero- or neonatal-onset muscle weakness of variable severity. In seven cases, severe muscle weakness resulted in death during the third trimester or shortly after birth. The remaining four cases had marked congenital or neonatal-onset hypotonia and weakness associated with mild-to-moderate facial and neck weakness, significant neonatal-onset respiratory and swallowing difficulties and childhood-onset spinal deformities. All four surviving cohort members experienced clinical improvement in the first decade of life. Muscle biopsies showed myopathic features including fibre size variability, presence of fibrofatty tissue of varying severity, without specific structural abnormalities. Electrophysiology suggested a myopathic process, without myotonia. In vitro functional assessment in HEK293 cells of the impact of the identified SCN4A mutations showed loss-of-function of the mutant Nav1.4 channels. All, apart from one, of the mutations either caused fully non-functional channels, or resulted in a reduced channel activity. Each of the affected cases carried at least one full loss-of-function mutation. In five out of six families, a second loss-of-function mutation was present on the trans allele. These functional results provide convincing evidence for the pathogenicity of the identified mutations and suggest that different degrees of loss-of-function in mutant Nav1.4 channels are associated with attenuation of the skeletal muscle action potential amplitude to a level insufficient to support normal muscle function. The results demonstrate that recessive loss-of-function SCN4A mutations should be considered in patients with a congenital myopathy.
- Published
- 2016
35. Cytosolic phosphoenolpyruvate carboxykinase deficiency presenting with acute liver failure following gastroenteritis
- Author
-
Mary Anne Preece, Britt I. Drögemöller, Colin J. D. Ross, Richard J. Rodenburg, Jessie M. Cameron, Casper Shyr, Wyeth W. Wasserman, Clara D.M. van Karnebeek, Ron A. Wevers, Girish Gupte, Lin-Hua Zhang, Saikat Santra, and Other departments
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Biology ,Biochemistry ,Consanguinity ,03 medical and health sciences ,Endocrinology ,PCK1 ,Internal medicine ,Genetics ,medicine ,Humans ,Exome ,Molecular Biology ,Exome sequencing ,Sequence Deletion ,Base Sequence ,Liver Diseases ,Intracellular Signaling Peptides and Proteins ,High-Throughput Nucleotide Sequencing ,Infant ,Metabolic Disorders Radboud Institute for Molecular Life Sciences [Radboudumc 6] ,Liver Failure, Acute ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,medicine.disease ,Gastroenteritis ,Pedigree ,Citric acid cycle ,Glucose ,030104 developmental biology ,Lactic acidosis ,Urea cycle ,Phosphoenolpyruvate Carboxykinase (GTP) ,Phosphoenolpyruvate carboxykinase ,Carbohydrate Metabolism, Inborn Errors ,Urine organic acids - Abstract
We report a patient from a consanguineous family who presented with transient acute liver failure and biochemical patterns suggestive of disturbed urea cycle and mitochondrial function, for whom conventional genetic and metabolic investigations for acute liver failure failed to yield a diagnosis. Whole exome sequencing revealed a homozygous 12-bp deletion in PCK1 (MIM 614168) encoding cytosolic phosphoenolpyruvate carboxykinase (PEPCK); enzymatic studies subsequently confirmed its pathogenic nature. We propose that PEPCK deficiency should be considered in the young child with unexplained liver failure, especially where there are marked, accumulations of TCA cycle metabolites on urine organic acid analysis and/or an amino acid profile with hyperammonaemia suggestive of a proximal urea cycle defect during the acute episode. If suspected, intravenous administration of dextrose should be initiated. Long-term management comprising avoidance of fasting with the provision of a glucose polymer emergency regimen for illness management may be sufficient to prevent future episodes of liver failure. This case report provides further insights into the (patho-)physiology of energy metabolism, confirming the power of genomic analysis of unexplained biochemical phenotypes. (C) 2016 Elsevier Inc. All rights reserved
- Published
- 2016
36. Effect of niacin on lipoproteins and atherosclerosis
- Author
-
Shobha H. Ganji, Vaijinath S. Kamanna, Moti L. Kashyap, and Lin-Hua Zhang
- Subjects
chemistry.chemical_classification ,medicine.medical_specialty ,Apolipoprotein B ,biology ,Chemistry ,digestive, oral, and skin physiology ,food and beverages ,nutritional and metabolic diseases ,Adipose tissue ,Fatty acid ,Inflammation ,Biochemistry ,Endocrinology ,Internal medicine ,medicine ,biology.protein ,lipids (amino acids, peptides, and proteins) ,medicine.symptom ,Receptor ,Niacin ,Lipoprotein ,Diacylglycerol kinase - Abstract
Niacin has been in use for the past 50 years to treat lipid disorders and atherosclerotic cardiovascular disease. We have recently demonstrated that niacin, by selective inhibition of liver diacylglycerol acyltransferae (DGAT)2, a rate-limiting enzyme in triglyceride synthesis, inhibits triglyceride synthesis thereby decreasing the secretion of apolipoprotein (Apo)B-containing very low-density lipoprotein and low-density lipoprotein particles. We have demonstrated that niacin increases ApoAI–high-density lipoprotein (HDL), mainly through the selective inhibition of hepatic uptake and removal of ApoAI–HDL (but not HDL-cholesterol ester). Emerging data from our laboratory provide evidence for the nonlipid-related effects of niacin on vascular oxidative and inflammatory processes involved in atherosclerosis. Although decreased free fatty acid mobilization from adipose tissue via a newly described niacin receptor (HM74A) is reported as a mechanism by which niacin decreases triglycerides, both physiologically ...
- Published
- 2006
- Full Text
- View/download PDF
37. Efficient Preparation of a Key Intermediate in the Synthesis of Roxifiban by Enzymatic Dynamic Kinetic Resolution on Large Scale
- Author
-
Edward Gorko, John A Blackwell, J. C. Chung, Lakisha Powell, Charlotte E. Silverman, Lin-hua Zhang, Jaan A. Pesti, Pat N. Confalone, Joseph M. Fortunak, Mary Cooke, Robert E. Waltermire, Anzalone Luigi, Jinguao Yin, Philip Ma, Michael D. Hrytsak, and Charles Ray
- Subjects
chemistry.chemical_classification ,Reaction conditions ,Pilot plant ,Chemistry ,Computational chemistry ,Yield (chemistry) ,Organic Chemistry ,Physical and Theoretical Chemistry ,Thioester ,Kinetic resolution - Abstract
Additional information is presented for the transformation of a kinetic resolution into a dynamic kinetic resolution of the isobutyl ester 5b to form the acid 2 in high yield and ee via the intermediacy of a thioester 6c, (Pesti, J. A.; Yin, J.; Zhang, L.-H; Anzalone, L. J. Am. Chem. Soc. 2001, 123, 11075−11076.). The development of optimized reaction conditions for the preparation of 6c, its dynamic kinetic resolution to 2, and the scale-up of both reactions into a pilot plant are described.
- Published
- 2003
- Full Text
- View/download PDF
38. Mutant frizzled-4 disrupts retinal angiogenesis in familial exudative vitreoretinopathy
- Author
-
Michael R. Hayden, Y. Paul Goldberg, A. Hoskin-Mott, Laird C. Sheldahl, Michael T. Trese, Marcia L.E. MacDonald, Marie-Pierre Dubé, Randall T. Moon, Simon N. Pimstone, Mark E. Samuels, J Zeisler, Lin-Hua Zhang, B. Zheng, Ajamete Kaykas, Barkur S. Shastry, Lee Siebert, Duane L. Guernsey, Johane M Robitaille, and Roshni R. Singaraja
- Subjects
Genetic Markers ,Male ,Frizzled ,FZD4 ,Molecular Sequence Data ,Xenopus ,Receptors, Cell Surface ,Retina ,Receptors, G-Protein-Coupled ,Retinal Diseases ,Ca2+/calmodulin-dependent protein kinase ,Genetics ,medicine ,Humans ,Amino Acid Sequence ,Protein kinase C ,Polymorphism, Genetic ,Neovascularization, Pathologic ,biology ,Wnt signaling pathway ,Proteins ,Retinal Vessels ,biology.organism_classification ,medicine.disease ,Frizzled Receptors ,Pedigree ,Cell biology ,Haplotypes ,Child, Preschool ,Mutation ,Familial exudative vitreoretinopathy ,Female ,Signal transduction ,Sequence Alignment ,Signal Transduction - Abstract
Familial exudative vitreoretinopathy (FEVR) is a hereditary ocular disorder characterized by a failure of peripheral retinal vascularization. Loci associated with FEVR map to 11q13-q23 (EVR1; OMIM 133780, ref. 1), Xp11.4 (EVR2; OMIM 305390, ref. 2) and 11p13-12 (EVR3; OMIM 605750, ref. 3). Here we have confirmed linkage to the 11q13-23 locus for autosomal dominant FEVR in one large multigenerational family and refined the disease locus to a genomic region spanning 1.55 Mb. Mutations in FZD4, encoding the putative Wnt receptor frizzled-4, segregated completely with affected individuals in the family and were detected in affected individuals from an additional unrelated family, but not in normal controls. FZD genes encode Wnt receptors, which are implicated in development and carcinogenesis. Injection of wildtype and mutated FZD4 into Xenopus laevis embryos revealed that wildtype, but not mutant, frizzled-4 activated calcium/calmodulin-dependent protein kinase II (CAMKII) and protein kinase C (PKC), components of the Wnt/Ca(2+) signaling pathway. In one of the mutants, altered subcellular trafficking led to defective signaling. These findings support a function for frizzled-4 in retinal angiogenesis and establish the first association between a Wnt receptor and human disease.
- Published
- 2002
- Full Text
- View/download PDF
39. Specific para-hydroxylation of nitronaphthalenes with cumene hydroperoxide in basic aqueous media
- Author
-
Lei Zhu and Lin-hua Zhang
- Subjects
Hydroxylation ,chemistry.chemical_compound ,chemistry ,Aqueous medium ,Cumene hydroperoxide ,Yield (chemistry) ,Organic Chemistry ,Drug Discovery ,Organic chemistry ,Selectivity ,Biochemistry - Abstract
A synthetic method for specific para -hydroxylation of nitroarenes has been developed. The reaction of nitronaphthalenes with cumeme hydroperoxide in basic aqueous media produces exclusively para -hydroxy nitronaphthalenes in good yield. The selectivity of ortho and para hydroxylation is mediated by water content. The rationale for water-controlled orientation of hydroxylation has been briefly discussed.
- Published
- 2000
- Full Text
- View/download PDF
40. Double nucleophilic addition. A new one-pot synthesis of 2-alkyl- and 2-phenyl-5-hydrazinopyridine from pyridine
- Author
-
Lin-hua Zhang and Zhulin Tan
- Subjects
chemistry.chemical_classification ,Nucleophilic addition ,Chemistry ,Organic Chemistry ,One-pot synthesis ,Dihydropyridine ,chemistry.chemical_element ,Biochemistry ,Medicinal chemistry ,chemistry.chemical_compound ,Reagent ,Drug Discovery ,Pyridine ,medicine ,Lithium ,Alkyl ,medicine.drug - Abstract
A new method for the synthesis of 2-alkyl- and 2-phenyl-5-hydrazinopyridine has been developed. Nucleophilic addition on pyridine by alkyl or phenyl lithium reagents generated a 2-substituted dihydropyridine anion that reacts with di- t -butyl azodicarboxylate to form 2,5-disubstituted dihydropyridine. Conversion of the dihydropyridines to pyridines was achieved by a mild air oxidation.
- Published
- 2000
- Full Text
- View/download PDF
41. Mutations in ABCA8 underlie reduced plasma high density cholesterol levels in humans
- Author
-
Federico Torta, C. Chai, G. Dalling-Thie, Michael R. Hayden, Roshni R. Singaraja, Kees Hovingh, Lin-Hua Zhang, Veronique Angeli, Chung Hwee Thiam, L. Trigueros Motos, Markus Rennie Wenk, and J. van Capelleveen
- Subjects
medicine.medical_specialty ,chemistry.chemical_compound ,Endocrinology ,Chemistry ,Cholesterol ,Internal medicine ,medicine ,High density ,Plasma ,Cardiology and Cardiovascular Medicine ,ABCA8 - Published
- 2015
- Full Text
- View/download PDF
42. Clinical, Biochemical, and Molecular Characterization of Novel Mutations in ABCA1 in Families with Tangier Disease
- Author
-
Simon W. Rabkin, Fudan Miao, Jiri Frohlich, David Cassiman, Jennifer A. Collins, Singh N. Sadananda, Michael R. Hayden, Clara D.M. van Karnebeek, Liam R. Brunham, Bryan Sayson, Martin H. Kang, Sylvia Stockler, and Lin-Hua Zhang
- Subjects
Proband ,Genetics ,Mutation ,biology ,Nonsense mutation ,nutritional and metabolic diseases ,medicine.disease ,Compound heterozygosity ,medicine.disease_cause ,Article ,Frameshift mutation ,Tangier disease ,ABCA1 ,medicine ,biology.protein ,Missense mutation - Abstract
Tangier disease is a rare, autosomal recessive disorder caused by mutations in the ABCA1 gene and is characterized by near absence of plasma high-density lipoprotein cholesterol, accumulation of cholesterol in multiple tissues, peripheral neuropathy, and accelerated atherosclerosis. Here we report three new kindreds with Tangier disease harboring both known and novel mutations in ABCA1. One patient was identified to be homozygous for a nonsense mutation, p.Gln1038*. In a remarkably large Tangier disease pedigree with four affected siblings, we identified compound heterozygosity for previously reported missense variants, p.Arg937Val and p.Thr940Met, and show that both of these mutations result in significantly impaired cholesterol efflux in transfected cells. In a third pedigree, the proband was identified to be compound heterozygous for two novel mutations, a frameshift (p.Ile1200Hisfs*4) and an intronic variant (c.4176-11T>G), that lead to the creation of a cryptic splice site acceptor and premature truncation, p.Ser1392Argfs*6. We demonstrate that this mutation arose de novo, the first demonstration of a pathogenic de novo mutation in ABCA1 associated with Tangier disease. We also report results of glucose tolerance testing in a Tangier disease kindred for the first time, showing a gene–dose relationship between ABCA1 activity and glucose tolerance and suggesting that Tangier disease patients may have substantially impaired islet function. Our findings provide insight into the diverse phenotypic manifestations of this rare disorder, expand the list of pathogenic mutations in ABCA1, and increase our understanding of how specific mutations in this gene lead to abnormal cellular and physiological phenotypes.
- Published
- 2014
- Full Text
- View/download PDF
43. Mitochondrial Carbonic Anhydrase VA Deficiency Resulting from CA5A Alterations Presents with Hyperammonemia in Early Childhood
- Author
-
Amit P. Bhavsar, Joy Yaplito-Lee, Casper Shyr, Anupam Chakrapani, Anna Lehman, Hilary Vallance, Theresa Newlove, Marion B. Coulter-Mackie, Mary Anne Preece, Graham Sinclair, Hien Nguyen, Colin J. D. Ross, Virginie Bernard, Wyeth W. Wasserman, Ramona Salvarinova, James Pitt, William S. Sly, Abdul Waheed, Henry Ukpeh, Saikat Santra, Patrice Eydoux, Lin-Hua Zhang, Clara D.M. van Karnebeek, Sylvia Stockler-Ipsiroglu, Gabriella Horvath, Sarah Ball, and Other departments
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Molecular Sequence Data ,Mutation, Missense ,Biology ,Carbonic Anhydrase V ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Report ,medicine ,Genetics ,Carglumic acid ,Missense mutation ,Humans ,Hyperammonemia ,Genetics(clinical) ,Child ,Genetics (clinical) ,030304 developmental biology ,0303 health sciences ,Splice site mutation ,Base Sequence ,Pyruvate carboxylase deficiency ,Homozygote ,Temperature ,Genetic Variation ,Infant ,Exons ,Sequence Analysis, DNA ,medicine.disease ,3. Good health ,Pyruvate carboxylase ,Pedigree ,Endocrinology ,chemistry ,Gluconeogenesis ,Liver ,Urea cycle ,Child, Preschool ,Female ,030217 neurology & neurosurgery ,Gene Deletion - Abstract
Four children in three unrelated families (one consanguineous) presented with lethargy, hyperlactatemia, and hyperammonemia of unexplained origin during the neonatal period and early childhood. We identified and validated three different CA5A alterations, including a homozygous missense mutation (c.697T>C) in two siblings, a homozygous splice site mutation (c.555G>A) leading to skipping of exon 4, and a homozygous 4 kb deletion of exon 6. The deleterious nature of the homozygous mutation c.697T>C (p.Ser233Pro) was demonstrated by reduced enzymatic activity and increased temperature sensitivity. Carbonic anhydrase VA (CA-VA) was absent in liver in the child with the homozygous exon 6 deletion. The metabolite profiles in the affected individuals fit CA-VA deficiency, showing evidence of impaired provision of bicarbonate to the four enzymes that participate in key pathways in intermediary metabolism: carbamoylphosphate synthetase 1 (urea cycle), pyruvate carboxylase (anaplerosis, gluconeogenesis), propionyl-CoA carboxylase, and 3-methylcrotonyl-CoA carboxylase (branched chain amino acids catabolism). In the three children who were administered carglumic acid, hyperammonemia resolved. CA-VA deficiency should therefore be added to urea cycle defects, organic acidurias, and pyruvate carboxylase deficiency as a treatable condition in the differential diagnosis of hyperammonemia in the neonate and young child.
- Published
- 2014
44. Regulation of ABCA1 protein expression and function in hepatic and pancreatic islet cells by miR-145
- Author
-
Stefanie L. Butland, Michael R. Hayden, Martin H. Kang, Alpana Bhattacharjee, Lin-Hua Zhang, Willeke de Haan, and Nadeeja Wijesekara
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Transfection ,Islets of Langerhans ,Mice ,Genes, Reporter ,Internal medicine ,Insulin-Secreting Cells ,microRNA ,medicine ,Glucose homeostasis ,Animals ,Homeostasis ,Humans ,Insulin ,3' Untranslated Regions ,Regulation of gene expression ,geography ,geography.geographical_feature_category ,Binding Sites ,biology ,Hep G2 Cells ,Islet ,MicroRNAs ,medicine.anatomical_structure ,Endocrinology ,Cholesterol ,Glucose ,Gene Expression Regulation ,ABCA1 ,biology.protein ,Hepatocytes ,lipids (amino acids, peptides, and proteins) ,Cardiology and Cardiovascular Medicine ,Pancreas ,Lipoproteins, HDL ,ATP Binding Cassette Transporter 1 - Abstract
Objective— The ATP-binding cassette transporter A1 (ABCA1) protein maintains cellular cholesterol homeostasis in several different tissues. In the liver, ABCA1 is crucial for high-density lipoprotein biogenesis, and in the pancreas ABCA1 can regulate insulin secretion. In this study, our aim was to identify novel microRNAs that regulate ABCA1 expression in these tissues. Approach and Results— We combined multiple microRNA prediction programs to identify 8 microRNAs that potentially regulate ABCA1. A luciferase reporter assay demonstrated that 5 of these microRNAs (miR-148, miR-27, miR-144, miR-145, and miR-33a/33b) significantly repressed ABCA1 3′-untranslated region activity with miR-145 resulting in one of the larger decreases. In hepatic HepG2 cells, miR-145 can regulate both ABCA1 protein expression levels and cholesterol efflux function. In murine islets, an increase in miR-145 expression decreased ABCA1 protein expression, increased total islet cholesterol levels, and decreased glucose-stimulated insulin secretion. Inhibiting miR-145 produced the opposite effect of increasing ABCA1 protein levels and improving glucose-stimulated insulin secretion. Finally, increased glucose levels in media significantly decreased miR-145 levels in cultured pancreatic beta cells. These findings suggest that miR-145 is involved in glucose homeostasis and is regulated by glucose concentration. Conclusions— Our studies demonstrate that miR-145 regulates ABCA1 expression and function, and inhibiting this microRNA represents a novel strategy for increasing ABCA1 expression, promoting high-density lipoprotein biogenesis in the liver, and improving glucose-stimulated insulin secretion in islets.
- Published
- 2013
45. Pictet-Spengler reaction in trifluoroacetic acid. Large scale synthesis of pyridoindolobenzodiazepine as an atypical antipsychotic agent
- Author
-
C. L. Ensinger, J. M. Rodgers, Walter E. Meier, P. Rajagopalan, Irina Cipora Jacobson, T. D. Costello, E. Wats, P. Ma, and Lin-Hua Zhang
- Subjects
chemistry.chemical_compound ,Pictet–Spengler reaction ,Diazepine ,medicine.drug_class ,Chemistry ,Organic Chemistry ,Drug Discovery ,medicine ,Trifluoroacetic acid ,Atypical antipsychotic ,Organic chemistry ,Ring (chemistry) ,Biochemistry - Abstract
Traditional syntheses of benzodiazepines involve a Bischler-Napieralski reaction which is a three step process and gives low overall yields. An attractive alternative is to construct the diazepine ring under Pictet-Spengler conditions. This paper reports the synthesis of a novel pyridoindolo-benzodiazepine as a potent atypical antipsychotic agent. The key step in the synthesis is the ring formation of the diazepine ring in neat trifluoroacetic acid.
- Published
- 1995
- Full Text
- View/download PDF
46. Differential effect of the rs4149056 variant in SLCO1B1 on myopathy associated with simvastatin and atorvastatin
- Author
-
Liam R. Brunham, G.K. Hovingh, P. J. Lansberg, Michael R. Hayden, Johan Wouter Jukema, Cedric J. Carter, Lin-Hua Zhang, Anton F. H. Stalenhoef, Colin J. D. Ross, Henk Visscher, John J. P. Kastelein, Bruce Carleton, Fudan Miao, Vascular Medicine, and ACS - Amsterdam Cardiovascular Sciences
- Subjects
medicine.medical_specialty ,Statin ,medicine.drug_class ,Atorvastatin ,Pharmacology ,Internal medicine ,Genetics ,Medicine ,cardiovascular diseases ,Myopathy ,Health aging / healthy living Cardiovascular diseases [IGMD 5] ,biology ,business.industry ,Case-control study ,statin ,nutritional and metabolic diseases ,Odds ratio ,SLCO1B1 ,Simvastatin ,Cohort ,biology.protein ,Molecular Medicine ,lipids (amino acids, peptides, and proteins) ,medicine.symptom ,business ,medicine.drug ,myopathy - Abstract
Statins reduce cardiovascular morbidity and mortality in appropriately selected patients. However, statin-associated myopathy is a significant risk associated with these agents. Recently, variation in the SLCO1B1 gene was reported to predict simvastatin-associated myopathy. The aim of this study was to replicate association of the rs4149056 variant in SLCO1B1 with severe statin-associated myopathy in a cohort of patients using a variety of statin medications and to investigate the association with specific statin types. We identified 25 cases of severe statin-associated myopathy and 84 controls matched for age, gender, statin type and dose. The rs4149056 variant in SLCO1B1 was not significantly associated with myopathy in this group as a whole. However, when subjects were stratified by statin type, the SLCO1B1 rs4149056 genotype was significantly associated with myopathy in patients who received simvastatin, but not in patients who received atorvastatin. Our findings provide further support for a role for SLCO1B1 genotype in simvastatin-associated myopathy, and suggest that this association may be stronger for simvastatin compared with atorvastatin. The Pharmacogenomics Journal (2012) 12, 233-237; doi: 10.1038/tpj.2010.92; published online 18 January 2011
- Published
- 2012
47. Reverse D4F, an apolipoprotein-AI mimetic peptide, inhibits atherosclerosis in ApoE-null mice
- Author
-
Shucun Qin, Vaijinath S. Kamanna, Shobha H. Ganji, William W. Bachovchin, Jack H. Lai, Lin-Hua Zhang, Tianjiao Liu, and Moti L. Kashyap
- Subjects
Apolipoprotein E ,medicine.medical_specialty ,Monocyte chemotaxis ,Peptide ,Inflammation ,Phenylalanine ,Lesion ,Mice ,Apolipoproteins E ,Internal medicine ,medicine ,Macrophage ,Animals ,Humans ,Pharmacology (medical) ,Aorta ,Chemokine CCL2 ,Pharmacology ,chemistry.chemical_classification ,Mice, Knockout ,Apolipoprotein A-I ,business.industry ,Macrophages ,Body Weight ,Endothelial Cells ,Atherosclerosis ,Lipids ,Coculture Techniques ,Endocrinology ,chemistry ,Female ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Peptides ,Lipoprotein - Abstract
Synthetic class A amphipathic helical peptide analogs of apolipoprotein-AI (apoAI; with varied phenylalanine residues) are emerging therapeutic approaches under investigation for atherosclerosis. Utilizing retroinverso sequencing, we designed reverse-D4F (Rev-D4F) peptide with 18 d-amino acids containing 4 phenylalanine residues and reverse order that allows the side chain residues to be of exact alignment and superimposable to those of the parent l-amino acid peptide. This study examined the effect of Rev-D4F on atherosclerosis in apolipoprotein E (apoE)-null mice and the underlying mechanisms.ApoE-null mice were fed a chow diet and administered water (control), Rev-D4F, or L4F mimetic peptides (0.4 mg/mL, equivalent to 1.6 mg/d) orally in drinking water for 6 weeks. Aortic root atherosclerotic lesion area, lesion macrophage content, and the ability of plasma high-density lipoprotein (HDL) to influence monocyte chemotaxis were measured.Rev-D4F significantly decreased aortic sinus atherosclerotic lesion area and lesion macrophage content without affecting plasma total and HDL-cholesterol levels in apoE-null mice. The HDL from Rev-D4F-treated mice showed enhanced anti-inflammatory monocyte chemotactic activity, while low-density lipoprotein (LDL) exhibited reduced proinflammatory activity. In in vitro studies, Rev-D4F inhibited LDL oxidation, endothelial cell vascular cell adhesion molecule 1 (VCAM-1), and monocyte chemotactic factor 1 (MCP-1) expression, and monocyte adhesion to aortic endothelial cells.The Rev-D4F inhibits atherosclerosis by inhibiting endothelial inflammatory/oxidative events and improving HDL function. The data suggest that Rev-D4F may be an effective apoAI mimetic peptide for further development in preventing atherosclerosis.
- Published
- 2012
48. Enantiospecific Synthesis of (-)-Alstonerine and (+)-Macroline as Well as a Partial Synthesis of (+)-Villalstonine
- Author
-
Linda K. Hamaker, Yingzhi Bi, James M. Cook, and Lin-Hua Zhang
- Subjects
Colloid and Surface Chemistry ,Villalstonine ,Chemistry ,Organic chemistry ,General Chemistry ,Alstonerine ,Biochemistry ,Catalysis - Published
- 1994
- Full Text
- View/download PDF
49. Facile detosylation of cyclic peptides. An effective synthesis of platelet glycoprotein IIb/IIIa inhibitors
- Author
-
Lin-Hua Zhang and P. Ma
- Subjects
chemistry.chemical_classification ,animal structures ,integumentary system ,Organic Chemistry ,Liquid phase ,Tripeptide ,Biochemistry ,Cyclic peptide ,chemistry.chemical_compound ,Platelet Glycoprotein IIb/IIIA Inhibitors ,chemistry ,embryonic structures ,Drug Discovery ,Antithrombotic ,Peptide synthesis ,Sequence (medicine) - Abstract
A general and effective synthesis of cyclic pentapeptides containing Arg-Gly-Asp sequence, which are potent antithrombotic agents, is reported.
- Published
- 1994
- Full Text
- View/download PDF
50. Reversal of the regioselectivity of anthrapyrazole formation. A new synthesis of losoxantrone (DUP941)
- Author
-
Walter E. Meier, Emily P. Gibson, Lin-Hua Zhang, and E. J. Watson
- Subjects
chemistry.chemical_compound ,chemistry ,Diamine ,Organic Chemistry ,Drug Discovery ,Organic chemistry ,Losoxantrone ,Regioselectivity ,Anthrapyrazole ,Nuclear Overhauser effect ,Biochemistry - Abstract
Losoxantrone, a potent anticancer agent, has been efficiently synthesized in a 6 step process from 5-hydroxy-1,4-dichloroanthracene-9,10-dione.
- Published
- 1994
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.