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The sluggish kinetics of oxygen evolution reaction (OER) is the key tailback for hydrogen production from the water electrolysis. Masking OER with thermodynamically auspicious methanol oxidation reaction (MOR) can significantly boost the H2 and value-added products production. However, it is currently challenging to achieve a synergistic manipulation of product selectivity and performance for MOR electrocatalyst. Herein, we report NiSnPH@OOH/CC (CC = carbon cloth) perovskite hydroxide nanosphere as an efficient MOR electrocatalyst with high activity, stability, and selectivity towards methanol oxidation to formate. A surface amorphous layer of defect rich NiOOH was generated in operando by selective Sn leaching with stable perovskite hydroxide bulk structure, which mitigates the oxidative power and optimizes the local coordination environment of the active NiOOH sites. In situ Raman combined with electrochemical studies further confirm the key active species, NiOOH, generated in operando enhance the MOR and blocking the over oxidation of methanol to CO2. As a result, NiSnPH@OOH/CC effectively masks the OER and attains > 99% selectivity with 100% Faradic efficiency for methanol-to-formate. The results of this study show the advances of NiSnPH@OOH/CC as an efficient electrocatalyst for MOR and also suggest its potential applications for various small organic molecules oxidation. [ABSTRACT FROM AUTHOR]

Investing heavily in the transition to renewable energy is essential for global sustainability. Companies in the renewable energy sector often use bank financing for day-to-day operations and capital expenditures. This research looks at the effect of financial ties between renewable energy companies and banks on both industries' viability as they make the switch to renewable power sources. We analyze a large worldwide sample of renewable energy firms and banks to see how these interdependencies affect the long-term viability of both industries. According to our findings, the effectiveness of the shift is heavily impacted by the degree of interconnection between renewable energy businesses and banks. Financing costs are reduced and investments in renewable energy projects are encouraged when banks have a higher exposure to renewable energy enterprises. In addition to highlighting the importance of these linkages, our research also emphasizes the possible hazards associated with them, such as financial contagion and systemic risk, and underscores the necessity for effective risk management methods. In conclusion, this study highlights the need for a coordinated strategy to the renewable energy transition that weighs the advantages and disadvantages of interconnection. We show that there are both positive and negative outcomes that can result from the relationship between financial institutions and renewable energy enterprises, and we highlight the duty of policymakers and regulators to ensure that banks have adequate exposure to the industry while closely monitoring associated risks. [ABSTRACT FROM AUTHOR]

Gallbladder carcinoma (GBC) is a lethal biliary tract malignant neoplasm. Patient-derived primary cancer cell lines (PDPCs) are appropriate models to explore biological characteristics and potential therapeutics; however, there is a lack of PDPCs in GBC. In this study, we aimed to establish and characterize the GBC PDPCs, and further investigated the intra-tumor heterogeneity (ITH). Multi-region sampling (3–9 regions) of the operable tumor tissue samples was used to establish PDPCs. Short tandem repeat genotyping for cell authentication and karyotyping was performed, followed by whole-exome sequencing and RNA sequencing to assess the ITH at the genetic and transcriptional levels, respectively. Thirty-eight PDPCs were successfully established from seven GBC patients and characterized. ITH was observed with a median of 38.3% mutations being heterogeneous (range, 26.6–59.4%) across all patients. Similar with other tumor types, TP53 mutations were always truncal. In addition, there were three genes, KMT2C, CDKN2A, and ARID1A, with truncal mutations in at least two patients. A median of 370 differentially expressed genes (DEGs) was identified per patient. Distinct expression patterns were observed between major histocompatibility complex (MHC) class I and II genes. We found the expression of MHC class II genes in the PDPC samples was closely regulated by CIITA, while that of MHC class I genes were not correlated with CIITA expression. The PDPCs established from GBC patients can serve as novel in vitro models to identify the ITH, which may pave a crucial molecular foundation for enhanced understanding of tumorigenesis and progression. [ABSTRACT FROM AUTHOR]

Background: Cholangiocarcinoma (CCA) is a rare malignant tumor of the biliary system. The heterogeneity of CCA leads to the lack of effective targeted treatment for CCA subtypes. The molecular characteristic of hilar CCA (hCCA) is still unclear. Methods: A total of 63 hCCA patients were enrolled from Shanghai Eastern Hepatobiliary Surgery Hospital. Formalin-fixed, paraffin-embedded tumor tissues, and matched blood were collected and deep sequencing targeting 450 cancer genes were performed. Tumor mutation burden (TMB) was measured by an algorithm developed in-house. Correlation analysis was performed by Fisher's exact test. Results: The most commonly mutated genes were TP53 (51.7%), NF1 and KRAS (20%, for both), SMAD4 (16.7%), FAT3 and FRS2 (13.3%, for both), NF1 (11.7%), and KMT2C, MDM2, and ATM (10%, for each) in hCCA. ARID1A, GATA6, and PREX2 mutations commonly occurred in female and KMT2C mutations mainly occurred in patients under 60 years old. Statistical analysis showed the association between ARID1A mutation and tumor stage (P = 0.041) and between NF1 mutation and high TMB (P = 0.0095). Furthermore, ARID1B mutation was identified to associate with the poor prognosis of Chinese hCCA patients (P = 0.004). Conclusion: The mutational characterization of hCCA is different from both extrahepatic CCA and intrahepatic CCA. ARID1B is a potential biomarker for prognosis prediction of Chinese hCCA patients. [ABSTRACT FROM AUTHOR]

Newly diagnosed HIV-positive men who have sex with men (NHMSM) are at high risk of mental health problems but may also develop post-traumatic growth (PTG). According to the Common Sense Model, illness perception (including both cognitive representation and emotional representation) affects coping and health-related outcomes. A cross-sectional survey was conducted to examine the associations between illness perception and PTG among 225 NHMSM in Chengdu, China. Linear regression analyses indicated that the constructs of emotional representation subscale (β = −0.49) and five cognitive representation subscales (timeline, consequence, identity, attribution to god’s punishment/will, and attribution to chance/luck) (β = −0.13 to −0.37) were negative correlates of PTG, while four other constructs of cognitive representation (coherence, treatment control, personal control, and attribution to carelessness) were positive correlates (β = 0.15 to 0.51). No moderating effects were observed. The associations between five cognitive representation subscales and PTG were fully-mediated via emotional representation. The results indicate that interventions promoting PTG among NHMSM are warranted and should alter illness perception, emotional representation in particular. Future studies should clarify relationships between cognitive representation and emotional representation, and extend similar research to other health-related outcomes and HIV-positive populations. [ABSTRACT FROM AUTHOR]

The Chinese alligator Alligator sinensis (Fauvel, 1879) is an endangered species endemic to China. Up to this date, very little is known about the regulation of its growth and development. Insulin-like growth factor binding protein-1 (IGFBP-1) plays essential roles in regulating vertebrate growth and development by modulating IGFs action. In this study, we cloned the full-length cDNA of Chinese alligator IGFBP-1 (caIGFBP-1) for the first time, which has an open reading frame (ORF) of 885-bp nucleotides encoding a peptide of 294 amino acid residues. The caIGFBP-1 contains all features of IGFBP-1 peptide with the conserved cysteine-rich N- and C-terminal domains and variable central L-domain. Multiple alignment analysis showed that caIGFBP-1 shares high identity in amino acid sequence with the IGFBP-1 s of American alligator Alligator mississippiensis (Daudin, 1802) (99.32%) and birds (66.32-74.53%). Phylogenetic tree analysis of IGFBP-1 amino acid sequences indicated that alligators cluster into bird branch. The caIGFBP-1 is widely expressed in all the examined tissues, the expression level is highest in liver, higher in kidney, moderate in pancreas, stomach, small intestine, and lower in ovary, muscle, lung, heart. During the hibernating period, the expression level of caIGFBP-1 was significantly reduced in liver, kidney, stomach, pancreas and small intestine, while did not significantly change in heart, lung, ovary and muscle. The caIGFBP-1 mRNA expression changes during the active and hibernating periods, which coincides with that of Chinese alligator IGF, implicating that it might play important roles in the IGF-mediated growth and development of Chinese alligator. [ABSTRACT FROM AUTHOR]

Passeriformes is the largest group within aves and the phylogenetic relationships between Passeriformes have caused major disagreement in ornithology. Particularly, the phylogenetic relationships between muscicapoidea and sylvioidea are complex, and their taxonomic boundaries have not been clearly defined. Our aim was to study the status of two bird species: Tarsiger cyanurus and Phoenicurus auroreus. Furthermore, we analyzed the phylogenetic relationships of Passeriformes. Complete mitochondrial DNA (mtDNA) sequences of both species were determined and the lengths were 16,803 (T. cyanurus) and 16,772 bp (P. auroreus), respectively. Thirteen protein-coding genes, 22 tRNA genes, two rRNA genes, and one control region were identified in these mtDNAs. The contents of A and T at the base compositions was significantly higher than the content of G and C, and this AT skew was positive, while the GC skew was negative. The monophyly of Passeriformes is divided into four major clades: Corvoidea, Sylvioidea, Passeroidea, and Musicicapoidea. Paridae should be separated from the superfamily Sylvioidea and placed within the superfamily Muscicapoidea. The family Muscicapidae and Corvida were paraphyly, while Carduelis and Emberiza were grouped as a sister taxon. The relationships between some species of the order passeriformes may remain difficult to resolve despite an effort to collect additional characters for phylogenetic analysis. Current research of avian phylogeny should focus on adding characters and taxa and use both effectively to obtain a better resolution for deeper and shallow nodes. [ABSTRACT FROM AUTHOR]

CD1, as the third family of antigen-presenting molecules, is previously only found in mammals and chickens, which suggests that the chicken and mammalian CD1 shared a common ancestral gene emerging at least 310 million years ago. Here, we describe CD1 genes in the green anole lizard and Crocodylia, demonstrating that CD1 is ubiquitous in mammals, birds, and reptiles. Although the reptilian CD1 protein structures are predicted to be similar to human CD1d and chicken CD1.1, CD1 isotypes are not found to be orthologous between mammals, birds, and reptiles according to phylogenetic analyses, suggesting an independent diversification of CD1 isotypes during the speciation of mammals, birds, and reptiles. In the green anole lizard, although the single CD1 locus and MHC I gene are located on the same chromosome, there is an approximately 10-Mb-long sequence in between, and interestingly, several genes flanking the CD1 locus belong to the MHC paralogous region on human chromosome 19. The CD1 genes in Crocodylia are located in two loci, respectively linked to the MHC region and MHC paralogous region (corresponding to the MHC paralogous region on chromosome 19). These results provide new insights for studying the origin and evolution of CD1. [ABSTRACT FROM AUTHOR]

In wireless sensor networks, maximizing the lifetime of a data gathering tree without aggregation has been proved to be NP-complete. In this paper, we prove that, unless P = NP, no polynomial-time algorithm can approximate the problem with a factor strictly greater than 2/3. The result even holds in the special case where all sensors have the same initial energy. Existing works for the problem focus on approximation algorithms, but these algorithms only find sub-optimal spanning trees and none of them can guarantee to find an optimal tree. We propose the first non-trivial exact algorithm to find an optimal spanning tree. Due to the NP-hardness nature of the problem, this proposed algorithm runs in exponential time in the worst case, but the consumed time is much less than enumerating all spanning trees. This is done by several techniques for speeding up the search. Featured techniques include how to grow the initial spanning tree and how to divide the problem into subproblems. The algorithm can handle small networks and be used as a benchmark for evaluating approximation algorithms. [ABSTRACT FROM AUTHOR]

Decabromodiphenyl ethane (DBDPE), a replacement for decabromodiphenyl ether (deca-BDE), was investigated in captive Chinese alligators from China. DBDPE was detected in adult tissues, neonates and eggs of Chinese alligators with concentrations ranging from 4.74-192, 0.24-1.94, and 0.01-0.51 ng g lipid weight, respectively. Compared to PBDEs and PCBs, DBDPE contamination was limited in Chinese alligators. Additionally, DBDPE concentrations in adult muscles were one to three orders of magnitude higher than those in neonates and eggs, suggesting the limited maternal transfer potential of DBDPE in Chinese alligators. This is the first study to report the occurrence of DBDPE in Chinese alligators. [ABSTRACT FROM AUTHOR]

The article presents study investigate the variation of the major histocompatibility complex (MHC) class IIb gene in Chinese alligator and to provide genetic information for conservation and management strategies. It mentions amplification of MHC using the primers designed by the sequence of Caiman crocodilus. It adds genetic distances between the wild population (WP) and the two captive populations were higher than that between the two captive populations.

Using mobile chargers in wireless rechargeable sensor networks is an option for charging all the nodes in the network. In order to achieve some performance requirement such as coverage, it is necessary to effectively schedule the mobile chargers to serve every node of the network. We notice that nearly all previous works on mobile charger scheduling assume that mobile chargers move along predetermined paths which are computed based on perfect priori information. In this paper, we consider the problem of scheduling mobile chargers in an on-demand way to maximize the covering utility. On receiving re-charging requests from the nodes, the mobile charger decides how to move itself. The covering utility is defined to quantify the effectiveness of event monitoring. We formulate the scheduling problem as an optimization one. We propose three heuristics for this problem after proving its NP-Completeness. We further generalize our solutions to accommodate the multiple mobile chargers case. Finally we evaluate our solutions through extensive simulations. [ABSTRACT FROM AUTHOR]

PCR amplification and direct sequencing of mitochondrial genes of target taxa with universal primers designed according to a public DNA database can provide valuable information for phylogenetic inferences. This study describes the design of universal primer sets for an amplified partial 12S rRNA gene and fourteen other complete genes (16S rRNA gene plus 13 protein-coding genes) from the mitochondrial genome of 21 crocodilian species. This provides useful tools for the study of genetic variability in Crocodilia at or below the species level. [ABSTRACT FROM AUTHOR]

HPLC using pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) was used to analyse mono-saccharides and oligo-saccharides in hydrolysates of lignocellulosic biomass. PMP derivatives, including those of mannose, rhamnose, cellobiose, glucose, xylose and arabinose, were separated within 14 min with detection at 254 nm. The method was also suitable for xylo-oligosaccharides (XOS): PMP derivatives of xylohexaose, xylopentaose, xylotetraose, xylotriose and xylobiose were well separated under the same conditions. The method was used to determine the mono-saccharide composition of Miscanthus and evaluate the production of XOS from enzymatic hydrolysis of crude xylan. [ABSTRACT FROM AUTHOR]

Our study used MHC class IIb gene exon3 complete sequence as markers to investigate genetic variability, selection and population differentiation in Chinese alligator. In this study, 282 bp MHC IIb exon3 complete sequence was got, none of the sequences contained insertions/deletions or stop codons, suggesting that all sequences might come from functional molecules in the genome. The neighbor-joining (NJ) tree revealed that Xuangzhou and Changxing populations were genetically close related, while Wild population showed the most diverse from the other. Gene flow (Nm) was very higher than one, suggesting that inter-group gene flow may have occurred. Furthermore, the results showed that MHC IIb gene might be a good molecular marker, we think that this technology could be used for Chinese alligator breeding and releasing in future. [ABSTRACT FROM AUTHOR]

The Chinese alligator ( Alligator sinensis) is one of the most endangered crocodilians in the world. In this study, 14 novel microsatellite loci were developed for this rare species via 454 high-throughput sequencing. These polymorphic microsatellites yielded an average of 2.93 alleles per locus among 40 individuals scored. The observed and expected heterozygosities ( H and H) ranged from 0.025 to 0.975 and from 0.025 to 0.651, with averages of 0.439 and 0.426, respectively. These microsatellite markers will be useful for individual identification, mate choice for captive breeding and other relevant genetic investigations of Chinese alligator. [ABSTRACT FROM AUTHOR]

In spite of popularity of TNF-α antagonist in the treatment of rheumatoid arthritis (RA), their modes of action are not fully understood. In the present study, we further explore the effects of gene transfer route of a TNF-α antagonist on arthritis. Recombinant adeno-associated virus 2 (rAAV2) encoding rat TNF receptor-immunoglobulin Fc (ratTNFR:Fc) fusion gene was injected intraarticularly in rats with collagen-induced arthritis (CIA). As revealed by examination of the clinical, radiographical, and histological aspects, local gene transfer of rAAV2/ratTNFR:Fc ameliorated the arthritis symptoms and inhibited the development of CIA. Compared with the vector control group, expressions of TNF-α, IL-1, and IFN-γ were down-regulated, and IL-10 release was up-regulated in the rAAV2/ratTNFR:Fc-treated group. Furthermore, administration of rAAV2/ratTNFR:Fc ameliorated the enlargement of spleen and significantly reduced spleen cell proliferation. Low level of nitric oxide (NO) in spleen was observed in CIA rats following the delivery of rAAV2/ratTNFR:Fc when compared to the vector control group. This study provides the evidence that intraarticular delivery of rAAV2/ratTNFR:Fc suppress the progression of arthritis by restoring the balance between pro-inflammatory and anti-inflammatory cytokines and inhibiting spleen cell proliferation. Our findings also implicate that the down-regulation of NO release on arthritis is involved in the anti-inflammatory mechanisms of TNF-α antagonist. [ABSTRACT FROM AUTHOR]

For the further characterization of foot-and-mouth disease virus (FMDV)-induced foot-and-mouth disease, we investigated the association between polymorphism of BoLA-DRB3 gene and FMD resistance/susceptibility of Wanbei cattle challenged with FMDV. One hundred cattle were challenged with FMDV and exon 2 of BoLA-DRB3 genes was amplified by hemi-nested polymerase chain reaction from asymptomatic animals and from animals with FMD. PCR products were characterized by the RFLP technique using restriction enzymes Hae III. The results revealed extensive polymorphisms, 6 RFLP patterns were identified. By analyzing alleles and genotypic frequencies between healthy and infection with FMD cattle, we found that allele Hae III A was associated with susceptibility to FMD in Wanbei cattle ( P < 0.05), whereas Hae III C was associated with resistance to FMD ( P < 0.01) and may have a strong protective effect against FMD. Hae IIICC and Hae III BC genotype were associated with resistance to FMD ( P < 0.01). By contrast, Hae III AA genotype was associated with susceptibility to FMD ( P < 0.01). Sequence analysis show that 89 amino acids were translated in exon 2 of BoLA-DRB3 and 13.70 % of nucleotide mutated, which resulted in 14.61 % of amino acid change. One PKC, one Tyr and one CAMP phosphorylation were increased; the hydrophobicity and secondary structure of proteins produced change after amino acid substitution. These results revealed that Wanbei cattle had the ability of resistance to disease by mutation which result changes of the protein structure to perform the regulation of the cell using different signaling pathways in the long process of choice evolution. [ABSTRACT FROM AUTHOR]

The bacterial communities in the soils from tea orchards and their adjacent wasteland in Anhui Province, China were analysed by nested PCR-DGGE technique combined with sequencing. DGGE profiles revealed that the DGGE patterns of different soils were similar to each other and the most intensely bands appeared in all lanes. The bacterial genetic diversity index of tea orchard soils was lower than that of wasteland. For the tea orchard soils, Shannon's diversity index decreased in the order: 45-year-old tea orchard >25-year-old tea orchard >7-year-old tea orchard >70-year-old tea orchard. The analysis of 16S rRNA gene sequences indicated that the fragments belong to Proteobacteria, Acidobacteria, TM7, Cyanobacteria and Firmicutes. A comprehensive analysis of the bacterial community structure in the tea orchard soils indicated the bacterial community was dominantly composed of Acidobacteria, followed by Proteobacteria (Gamma and Alpha), Firmicutes, Cyanobacteria and candidate division TM7 . The RDA combined with UPGMA clustering analysis showed that the more similar the environmental variables were, the more similar the bacterial community structures in tea orchard soils were. [ABSTRACT FROM AUTHOR]

The accelerator complex of the China Spallation Neutron Source (CSNS) consists of a H linear accelerator (linac) and a rapid cycling synchrotron (RCS). The linac contains a Penning surface H ion source. The designed energy and the beam current of the source are 50 keV and 20 mA respectively, with a normalized root mean square (norm. rms.) emittance of 0.2π mm mrad. The manufactures and tests of the discharge chamber are in great progress. The construction of H ion source test stand has been completed, and the operation of the source is also in progress. Stable H ion beams with energy of 50 keV and current up to 50 mA are attained. Emittance measurement for the H beam is being prepared. [ABSTRACT FROM AUTHOR]

The complete sequences of the mitochondrial DNA genomes of Panthera tigris, Panthera pardus, and Panthera uncia were determined using the polymerase chain reaction method. The lengths of the complete mitochondrial DNA sequences of the three species were 16990, 16964, and 16773 bp, respectively. Each of the three mitochondrial DNA genomes included 13 protein-coding genes, 22 tRNA, two rRNA, one OR, and one control region. The structures of the genomes were highly similar to those of Felis catus, Acinonyx jubatus, and Neofelis nebulosa. The phylogenies of the genus Panthera were inferred from two combined mitochondrial sequence data sets and the complete mitochondrial genome sequences, by MP (maximum parsimony), ML (maximum likelihood), and Bayesian analysis. The results showed that Panthera was composed of Panthera leo, P. uncia, P. pardus, Panthera onca, P. tigris, and N. nebulosa, which was included as the most basal member. The phylogeny within Panthera genus was N. nebulosa ( P. tigris ( P. onca ( P. pardus, ( P. leo, P. uncia)))). The divergence times for Panthera genus were estimated based on the ML branch lengths and four well-established calibration points. The results showed that at about 11.3 MYA, the Panthera genus separated from other felid species and then evolved into the several species of the genus. In detail, N. nebulosa was estimated to be founded about 8.66 MYA, P. tigris about 6.55 MYA, P. uncia about 4.63 MYA, and P. pardus about 4.35 MYA. All these estimated times were older than those estimated from the fossil records. The divergence event, evolutionary process, speciation, and distribution pattern of P. uncia, a species endemic to the central Asia with core habitats on the Qinghai-Tibetan Plateau and surrounding highlands, mostly correlated with the geological tectonic events and intensive climate shifts that happened at 8, 3.6, 2.5, and 1.7 MYA on the plateau during the late Cenozoic period. [ABSTRACT FROM AUTHOR]

Technology for monitoring in vivo microRNA (miRNA) activity is extremely important for elucidating miRNA biology. However, in vivo studies of miRNA have been hampered by the lack of a convenient approach to reliably reflect real-time functional changes in miRNAs. Sensors for miRNA were developed by adding miRNA target sequences to the 3′-untranslated region of Gaussia princeps luciferase ( Gluc) mRNA. These sensors were then evaluated in vitro and in vivo by measuring Gluc activity in cell supernatants and in peripheral blood. Sensors driven by the CMV promoter were effective for monitoring miR-122 in living cells, but not for the long-term monitoring of miR-122 or miR-142 in mouse liver because of CMV-promoter silencing. Replacing the CMV promoter with a CAG promoter rendered these sensors effective for the long-term monitoring of relevant liver miRNA activities. We subsequently used the CAG-promoter-based sensor for the long-term monitoring of endogenous liver miR-122, miR142 and miR-34a activities, as well as for exogenous miR-34a activity. Our study demonstrates that real-time in vivo activities of miRNAs can be continuously and conveniently detected in mouse liver using the sensors that we have developed. [ABSTRACT FROM AUTHOR]

The variation of the exon 2 of the major histo-compatibility complex (MHC) class II gene DRB locus in three feline species were examined on clouded leopard ( Neofelis nebulosa), leopard ( Panthera pardus) and Amur tiger ( Panthera tigris altaica). A pair of degenerated primers was used to amplify DRB locus covering almost the whole exon 2. Exon 2 encodes the β1 domain which is the most variable fragments of the MHC class II molecule. Single-strand conformational polymorphism (SSCP) analysis was applied to detect different MHC class II DRB haplotypes. Fifteen recombinant plasmids for each individual were screened out, isolated, purified and sequenced finally. Totally eight distinct haplotypes of exon 2 were obtained in four individuals. Within 237 bp nucleotide sequences from four samples, 30 variable positions were found, and 21 putative peptide-binding positions were disclosed in 79 amino acid residues. The ratio of nonsynonymous substitutions ( d N ) was much higher than that of synonymous substitutions ( d S ), which indicated that balancing selection probably maintain the variation of exon 2. MEGA neighbor joining (NJ) and PAUP maximum parsimony (MP) methods were used to reconstruct phylogenetic trees among species, respectively. Results displayed a more close relationship between leopard and tiger; however, clouded leopard has a comparatively distant relationship form the other two. [ABSTRACT FROM AUTHOR]

Ethanol is the main byproduct of anaerobic H2-producing fermentation in Klebsiella oxytoca HP1. Two moles of NAD(P)H are consumed to yield one mole of ethanol that may decrease bacterial hydrogen production. In this article the adhE gene that codes for acetaldehyde dehydrogenase was disrupted for the first time. A homologous recombination vector pTA-Str was constructed in which the adhE gene was disrupted by inserting an aminoglycoside-3′-adenyltransferase (aadA) gene. As expected, the vector includes the insertion 5′-adhE-aadA-adhE-3′. The amplified DNA fragment 5′-adhE-aadA-adhE-3′ from pTA-Str was transformed into K. oxytoca HP1 and one recombinant was obtained. PCR analysis of the resulting genomic DNA indicated the appropriate deletion and insertion. Compared with the H2-production of wild type K. oxytoca HP1, the hydrogen yield of the mutant increased by 16.07% and ethanol concentration decreased by 77.47%, suggesting that inactivation of the adhE gene in K. oxytoca HP1 is a potential method for enhancing bacterial H2-production. [ABSTRACT FROM AUTHOR]

Cellulose is a kind of renewable resource that is abundant in nature. It can be degraded by microorganisms such as mildew. A mildew strain with high cellulase activity was isolated from mildewy maize cob and classified as Aspergillus glaucus XC9 by morphological and 18S rRNA gene sequence analyses. We studied the effects of nitrogen source, initial pH, temperature, incubation time, medium composition, and surfactants on cellulase production. Maximal activities of carboxymethylcellulase (6,812 U/g dry koji) and filter paperase (172 U/g dry koji) were obtained in conditions as follows: initial pH, 5.5–6.0; temperature, 30°C; cultivation period, 3–4 days; inoculum ratio, 6% (vol/vol); sugarcane bagasse/wheat bran ratio, 4:6. When bagasse was used as substrate and mixed with wet koji at a 1:1 (wt/wt) ratio, the yield of reducing sugars was 36.4%. The corresponding conversion rate of cellulose to reducing sugars went as high as 81.9%. The results suggest that A. glaucus XC9 is a preferred candidate for cellulase production. [ABSTRACT FROM AUTHOR]

Studies the complete mitochondrial DNA sequence of Chinese alligator, Alligator sinensis, and phylogeny of crocodiles. Study methods; Composition of bases; Difference of the gene arrangement from the common vertebrate gene arrangement.

Describes the recombinant adeno-associated viral vector with human coagulation factor IX minigene which was regulated by cytomegalovirus promoter. Preparation of large quantity of recombinant adeno-associated viral particles; Intramuscular injection of viral vectors in the quadriceps femoris; Elevation of human factor IX expression in the plasma of hemophilia B mice.

Recombinant adeno-associated virus (rAAV) has proven to be a promising gene delivery vector for human gene therapy. However, its application has been limited by difficulty in obtaining enough quantities of high-titer vector stocks. In this paper, a novel and highly efficient production system for rAAV is described. A recombinant herpes simplex virus type 1 (rHSV-1) designated HSV1-rc/ΔUL2, which expressed adeno-associated virus type2 (AAV-2) Rep and Cap proteins, was constructed previously. The data confirmed that its functions were to support rAAV replication and packaging, and the generated rAAV was infectious. Meanwhile, an rAAV proviral cell line designated BHK/SG2, which carried the green fluorescent protein (GFP) gene expression cassette, was established by transfecting BHK-21 cells with rAAV vector plasmid pSNAV-2-GFP. Infecting BHK/SG2 with HSV1-rc/ΔUL2 at an MOI of 0.1 resulted in the optimal yields of rAAV, reaching 250 transducing unit (TU) or 4.28×104 particles per cell. Therefore, compared with the conventional transfection method, the yield of rAAV using this “one proviral cell line, one helper virus” strategy was increased by two orders of magnitude. Large-scale production of rAAV can be easily achieved using this strategy and might meet the demands for clinical trials of rAAV-mediated gene therapy. [ABSTRACT FROM AUTHOR]

A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associated viral vector containing hFIXR338A, prepared by rHSV/AAV hybrid helper virus system, was directly introduced to the hind leg muscle of factor IX knock out mice. The expression and the biological activity of human factor IX mutant, hFIXR338A, and the immune response against it in the treated mice were assayed and detected. The results showed that (i) the high-level expression of human factor IX mutant protein, hFIXR338A, has been detected in rAAV-hFIXR338A treated hemophilia B mice and lasted more than 15 weeks; (ii) the clotting activity of hFIXR338A in plasma is 34.2%±5.23%, which is remarkably higher than that of (14.27% ± 3.4%) of wild type hFIX treated mice in the activated partial thromboplastin assay; (iii) immune response against factor IX R338A was absent, with no factor IX mutant protein (hFIXR338A) inhibitors development in the treated mice; and (iv) no local or systemic side-effects and toxicity associated with the gene transfer were found. It demonstrated the potential use of treating hemophilia B by recombinant adeno-associated viral vectors with mutant hFIXR338A gene, an alternative strategy for hemophilia B gene therapy to wild-type human factor IX. [ABSTRACT FROM AUTHOR]

Background: Epothilone compounds (e.g. epothilones A and B) represent a new structural class of microtubule inhibitors with the remarkable ability to inhibit tumor growth of multidrug-resistant cell lines at low nanomolar or even subnanomolar concentrations. Unfortunately, this therapeutic efficacy has only been achieved to date with a narrow therapeutic window. Hence, other structural analogs of compounds such as epothilone B are currently being synthesized in the hope that they will demonstrate equivalent antitumor efficacy with reduced systemic toxicity.Purpose: To evaluate the relative efficacy and toxicity of selectively modified epothilone compounds.Methods: Compounds were initially screened for relative cytotoxicity against the human prostate cancer cell lines PC3, LNCaP, MDA PCa 2a and MDA PCa 2b. Growth inhibitory IC50 values of 0.5 to 4 nM were obtained. From this initial screen, one epothilone compound, 26-fluoroepothilone B, was chosen for further evaluation against the growth of s.c.-implanted MDA PCa 2b- and PC3-derived prostate tumors in athymic nude mice. The compound was administered intravenously at 2, 5 and 10 mg/kg after the tumors had reached 300 mm3. Two control groups were used: paclitaxel (40 mg/kg) and saline.Results: Following treatment with 10 mg 26-fluoroepothilone B/kg, there was a sustained decrease in tumor size for 30 days reaching a maximal reduction of 80% when compared with tumor growth in the saline control group. Sustained suppression (> 20 days) of tumor growth was observed following the second drug injection. Although a maximal body weight loss of 30% occurred after the second injection, all mice completely regained their initial body weight in 20 days. A lower dose (2 mg/kg) produced a 58% maximal reduction in tumor size and a 20% body weight loss. Minimal inhibition of tumor growth, however, was obtained with paclitaxel at a maximally tolerated dose (40 mg/kg). Other epothilones tested were either less effective and/or more toxic than 26-fluoroepothilone B. This new fluorinated epothilone compound supports the growth of paclitaxel-dependent Tax-18 mutant CHO cells and produces microtubule bundles similar to those produced by paclitaxel, indicating that the two drugs share a similar mechanism of action.Conclusion: A new fluorinated epothilone compound, 26-fluoroepothilone B, has been described that stabilizes microtubule structures based on its support of growth of a mutant paclitaxel-dependent CHO cell line. Its antitumor activity against human prostate cancer in nude mice is superior to that of paclitaxel at equivalent toxic doses. Further research is required to determine optimal dosing strategies and to fully assess the compound's activity against other malignant diseases. [ABSTRACT FROM AUTHOR]

Focuses on a study which described the generation of a recombinant herpes simplex virus that can provide packaging function for recombinant adeno-associated virus production. Materials and methods; Results; Discussion of results.

A novel packaging system for producing recombinant adeno-associated virus (rAAV) vector was described. Instead of the conventional method for rAAV production by two-plasmid co-transfection followed by superinfection with adenovirus 5, an HSV-1 amplicon system expressing AAV-2 rep and cap genes from their native promoters was used to provide complete helper functions for rAAV replicating and packaging. This HSV-1 amplicon stock consisted of two kinds of infectious HSV-1 virions, a replicating-defective HSV-I amplicon pseudovirus harboring multi-copies of AAV-2 rep and cap gene and a temperature-sensitive HSV-1 mutant strain ts-KOS. High-titer rAAV was generated with this new packaging system. This packaging system gives a simple and scaleable process for rAAV production. [ABSTRACT FROM AUTHOR]

Crocodilians are a group of reptiles that are closely related to birds and are thought to possess a strong immune system. Here we report that the IgH locus in the Siamese crocodile and the Chinese alligator contains multiple ? genes, in contrast to other tetrapods. Both the ?2 and ?3 genes are expressed through class-switch recombination involving the switch region and germline transcription. Both IgM1 and IgM2 are present in the serum as polymers, which implies that IgM class switching may have significant roles in humoural immunity. The crocodilian ? genes are the first IgA-encoding genes identified in reptiles, and these genes show an inverted transcriptional orientation similar to that of birds. The identification of both ? and ? genes in crocodilians suggests that the IgH loci of modern living mammals, reptiles and birds share a common ancestral organization. [ABSTRACT FROM AUTHOR]