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Objective: The management of long-segment ureteral stenosis has posed a significant challenge for urologists. Ureteroplasty with oral mucosal graft has emerged as an effective approach for treating long-segment ureteral stenosis and defects. A key step in replacement repair surgery involves suturing the surrounding tissue with an adequate blood supply around the reconstructed ureter. The current study aims to evaluate the potential practical application of the "perinephric fat wrapping" technique in laparoscopic ureteroplasty with oral mucosal graft., Methods: Between July 2018 and February 2023, 26 patients with ureteral stenosis underwent laparoscopic ureteroplasty with oral mucosal graft at the Second Affiliated Hospital of Anhui Medical University. We used traditional omental wrapping technique (OW group) or perinephric fat wrapping technique (PFW group) to enhance ureter repair. Perioperative and follow-up data for both groups were collected retrospectively and compared., Results: There were 10 patients in OW group, including 4 males and 6 females, with BMI of 23.5±2.8 kg/m2 and stenosis length of 3.6±1.6 cm. There were 16 patients in the PFW group, including 10 males and 6 females, with a BMI of 26.1±3.3 kg/m2 and a median stenosis length of 2.3 cm (range, 1.2~6.0 cm). The operation of both groups was successfully completed, and no serious complications occurred during the operation. The mean operating time (OT) in the OW group was 200.6±41.9 min, the estimated amount of blood loss (EBL) was 25 ml (range, 10~30ml), and the median length of postoperative hospital stay (LHS) was 7.5 days (range 4.0~14.0 days). In the PFW group, the mean operating time (OT) was 211.9±38.3 min, the estimated blood loss (EBL) was 25 ml (range, 5~150ml), and the postoperative hospital stay (LHS) was 6.8±2.0 d. There was no significant difference between the two groups in the above indexes. Postoperative anal exhaust time was 1.0 d (range, 1.0~2.5d) in the PFW group and 1.9±0.5 d in the OW group, with significant difference between the two groups (P=0.009). The mean follow-up time was 36.8±15.9 months, and there was no significant difference between OW group and PFW group in the curative effect of operation., Conclusion: Perinephric fat wrapping technique not only avoids the potential effects of using omentum on abdominal organs, it is also as safe and effective as omentum wrapping technique in repairing and reconstructing the ureter using oral mucosal grafts., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Single-molecule localization microscopy (SMLM) based on temporal-focusing multiphoton excitation (TFMPE) and single-wavelength excitation is used to visualize the three-dimensional (3D) distribution of spontaneously blinking fluorophore-labeled subcellular structures in a thick specimen with a nanoscale-level spatial resolution. To eliminate the photobleaching effect of unlocalized molecules in out-of-focus regions for improving the utilization rate of the photon budget in 3D SMLM imaging, SMLM with single-wavelength TFMPE achieves wide-field and axially confined two-photon excitation (TPE) of spontaneously blinking fluorophores. TPE spectral measurement of blinking fluorophores is then conducted through TFMPE imaging at a tunable excitation wavelength, yielding the optimal TPE wavelength for increasing the number of detected photons from a single blinking event during SMLM. Subsequently, the TPE fluorescence of blinking fluorophores is recorded to obtain a two-dimensional TFMPE-SMLM image of the microtubules in cancer cells with a localization precision of 18±6 nm and an overall imaging resolution of approximately 51 nm, which is estimated based on the contribution of Nyquist resolution and localization precision. Combined with astigmatic imaging, the system is capable of 3D TFMPE-SMLM imaging of brain tissue section of a 5XFAD transgenic mouse with the pathological features of Alzheimer's disease, revealing the distribution of neurotoxic amyloid-beta peptide deposits., (© 2024 Wiley-VCH GmbH.)

The complex processes of neuron differentiation and neuron repair are critical for treating nervous system injuries and neurodegenerative diseases. Neurite outgrowth plays a crucial role in these processes by enabling the formation of connections between neurons and the generation of neuroplasticity to restore the function of the nervous system. In this study, we fabricated functionalized carbon dots (CDs) with distinctive photoluminescence and low cytotoxicity for use as fluorescence imaging probes and nanocarriers to deliver plasmid DNAs to neurons effectively for inducing neurite outgrowth. CDs were prepared through a reflux process in nitric acid solution, and their surface was then modified using polyethylenimine (PEI) to obtain positively charged CDs for increasing the absorption of plasmid DNAs and the efficiency of cell uptake. Experimental results indicated that the fabricated CDs maintained a low cytotoxicity and exhibited a high neuron uptake of up to 97%. An improvement in the plasmid DNA ingestion of neurons resulted in enhanced expression of Rab13-Q67L and Rab14 proteins, which considerably promoted neurite sprouting and elongation. After the fabricated PEI-modified CDs were used to deliver the Rab13-Q67L and Rab14 plasmids, more than 56% of the neurons had a neurite length that was greater than twice the size of their soma. Thus, DNA delivery through functionalized CDs has a high potential for use in gene therapy for neuronal injuries and diseases.

A small-sized chromophore, BTTA-2OH, manifesting favorable solubility, large two-photon excitation efficiency, and good fluorescence photostability was synthesized to label the membrane of living cells for visualizing the dynamic movement of membrane-related vesicles via a two-photon fluorescence imaging technique based on wavelength-tunable temporal-focusing multiphoton excitation microscopy.

Objectives: To explore the effects of acupoint application therapy (AAT) with TianGui Powder (TGP) on the expressions of the transforming growth factor β1 (TGF-β1) and Smad-2/3 signaling pathway in ovariectomized osteoporosis rats., Methods: Sixty rats were randomly divided into four groups: normal group (group A), model group (group B), TGP group (group C), and Western medicine group (group D). Group A had only the corresponding amount of adipose tissue around the ovary removed; rats in the other groups had bilateral ovariectomies. After 1 week, groups A and B were given 1 mL/100 mg normal saline solution by gavage, group C was treated with AAT with TGP on ShenQue acupoint (0.2 piece/rat, 6 h/time, 1 time/d) and group D was given calcium carbonate vitamin D3 (36 mg/kg/d) and alfacalcidol (0.05 μg/kg/d) tablet suspension. In this study, the bone mineral density (BMD) , the levels of BALP, TRAP-5b, and BGP in serum and the changes in bone histomorphology was detected. For acquiring lumbar experimental data, the expression of TGF-β1, Smad-2/3 proteins and mRNA of TGF-β1and Smad-2/3 were assessed. After 12 weeks, the data were collected for analysis., Results: Compared with group A, the bone trabecula was thinner and significantly reduced in other groups. The result of BMD improved significantly in both groups C and D compared to group B after intervention (P < 0.05). In contrast, compared to group B, the levels of BALP, TRAP-5b, and BGP significantly declined in both groups C and D. In group C, the results of protein expressions in TGF-β1, Smad-2/3 were 2.870 ± 0.270, 1.552 ± 0.111, and 1.420 ± 0.079, respectively. In groups C and D, those indications significantly declined compared to group B (P < 0.01). In group C, the level of mRNA expressions of TGF-β1, Smad-2/3 were 1.872 ± 0.177, 1.672 ± 0.086, and 1.790 ± 0.136, respectively. Compared with group B, those indications had significant difference in groups C and D (P < 0.05)., Conclusion: Acupoint application therapy with TGP could significantly improve the BMD. The TGF-β1 and Smad-2/3 signaling pathway could be a therapeutic target of TGP in postmenopausal osteoporosis rats., (© 2019 The Authors. Orthopaedic Surgery published by Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.)

The present study aimed to examine how the long non‑coding RNA (lncRNA) RP11‑543N12.1 interacted with microRNA (miR)‑324‑3p to modify microglials (MIs)‑induced neuroblastoma cell apoptosis, which may pose benefits to the treatment of Alzhemier's disease (AD). The cell model of AD was established by treating SH‑SY5Y cells with amyloid β (Aβ)25‑35, and MI were acquired using primary cell culture technology. The lncRNAs that were differentially expressed between SH‑SY5Y and control cells were screened through a microarray assay and confirmed via polymerase chain reaction. In addition, overexpression of RP11‑543N12.1 and miR‑324‑3p was established by transfection of SH‑SY5Y cells with pcDNA3.1(+)‑RP11‑543N12.1 and miR‑324‑3p mimics, respectively, while downregulation of RP11‑543N12.1 and miR‑324‑3p was achieved by transfection with RP11‑543N12.1‑small interfering RNA (siRNA) and miR‑324‑3p inhibitor, respectively. The interaction between RP11‑543N12.1 and miR‑324‑3p was confirmed with a dual‑luciferase reporter gene assay. The results revealed that the expression levels of total and phosphorylated tau in SH‑SY5Y cells were significantly elevated following Aβ25‑35 treatment (P<0.05), and RP11‑543N12.1 was found to be differentially expressed between the control and Aβ25‑35‑treated cells (P<0.05). Furthermore, the targeted association of RP11‑543N12.1 and miR‑324‑3p was predicted based on miRDB4.0 and PITA databases, and then validated via the dual‑luciferase reporter gene assay. SH‑SY5Y cells transfected with siRNA or inhibitor, and treated with Aβ25‑35 displayed cellular survival and apoptosis that were similar to the normal levels (P<0.05). Finally, co‑culture of MI and SH‑SY5Y cells transfected with RP11‑543N12.1‑siRNA/miR‑324‑3p inhibitor significantly enhanced cell apoptosis (P<0.05). In conclusion, RP11‑543N12.1 targeted miR‑324‑3p to suppress proliferation and promote apoptosis in the AD cell model, suggesting that RP11‑543N12.1 and miR‑324‑3p may be potential biomarkers and therapeutic targets for AD.

Acetoin is an important platform chemical with a variety of applications in foods, cosmetics, chemical synthesis, and especially in the asymmetric synthesis of optically active pharmaceuticals. It is also a useful breath biomarker for early lung cancer diagnosis. In order to enhance production of optical ( S )-acetoin and facilitate this building block for a series of chiral pharmaceuticals derivatives, we have developed a systematic approach using in situ -NADH regeneration systems and promising diacetyl reductase. Under optimal conditions, we have obtained 52.9 g L -1 of ( S )-acetoin with an enantiomeric purity of 99.5% and a productivity of 6.2 g (L h) -1 . The results reported in this study demonstrated that the production of ( S )-acetoin could be effectively improved through the engineering of cofactor regeneration with promising diacetyl reductase. The systematic approach developed in this study could also be applied to synthesize other optically active α-hydroxy ketones, which may provide valuable benefits for the study of drug development., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: The relationship between protein structure and its bioactivity is one of the fundamental problems for protein engineering and pharmaceutical design., Method: A new method, called SPTD (Simulated Protein Thermal Detection), was proposed for studying and improving the thermal stability of enzymes. The method was based on the evidence observed by conducting the MD (Molecular Dynamics) simulation for all the atoms of an enzyme vibrating from the velocity at a room temperature (e.g., 25°C) to the desired working temperature (e.g., 65°C). According to the recorded MD trajectories and the coordinate deviations of the constituent residues under the two different temperatures, some new strategies have been found that are useful for both drug delivery and starch industry., Conclusion: The SPTD technique presented in this paper may become a very useful tool for pharmaceutical design and protein engineering., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Dental caries is one of the most common chronic diseases and is caused by acid fermentation of bacteria adhered to the teeth. Streptococcus mutans (S. mutans) utilizes sortase A (SrtA) to anchor surface proteins to the cell wall and forms a biofilm to facilitate its adhesion to the tooth surface. Some plant natural products, especially several flavonoids, are effective inhibitors of SrtA. However, given the limited number of inhibitors and the development of drug resistance, the discovery of new inhibitors is urgent. Here, the high-throughput virtual screening approach was performed to identify new potential inhibitors of S. mutans SrtA. Two libraries were used for screening, and nine compounds that had the lowest scores were chosen for further molecular dynamics simulation, binding free energy analysis and absorption, distribution, metabolism, excretion and toxicity (ADMET) properties analysis. The results revealed that several similar compounds composed of benzofuran, thiadiazole and pyrrole, which exhibited good affinities and appropriate pharmacokinetic parameters, were potential inhibitors to impede the catalysis of SrtA. In addition, the carbonyl of these compounds can have a key role in the inhibition mechanism. These findings can provide a new strategy for microbial infection disease therapy.

A method, so called "active hydrogen bond network" (AHBN), is proposed for site-directed mutations of hydrolytic enzymes. In an enzyme the AHBN consists of the active residues, functional residues, and conservative water molecules, which are connected by hydrogen bonds, forming a three dimensional network. In the catalysis hydrolytic reactions of hydrolytic enzymes AHBN is responsible for the transportation of protons and water molecules, and maintaining the active and dynamic structures of enzymes. The AHBN of pullulanase BNPulA324 from Bacillus naganoensis was constructed based on a homologous model structure using Swiss Model Protein-modeling Server according to the template structure of pullulanase BAPulA (2WAN). The pullulanase BNPulA324 are mutated at the mutation sites selected by means of the AHBN method. Both thermal stability and pH-sensitivity of pullulanase BNPulA324 were successfully improved. The mutations at the residues located at the out edge of AHBN may yield positive effects. On the other hand the mutations at the residues inside the AHBN may deprive the bioactivity of enzymes. The AHBN method, proposed in this study, may provide an assistant and alternate tool for protein rational design and protein engineering., Competing Interests: The authors have declared that no competing interests exist.

Objectives: To preliminarily assess the effects of Bushen Huoxue Granule (BHG) on Parkinson's Patients with Parkinson's Disease Questionnaire-39 (PDQ-39)and to provide data for further research., Design: A randomized, double-blinded, placebo controlled study with a 3-month intervention period and a 6-month follow-up., Interventions: Participants were patients with Parkinson's Disease (PD) of age ranging from 50 to 80 years and Hoehn and Yahr (H-Y) stage I-IV of the disease.120 participants were allocated to BHG group or placebo group at a 1:1 ratio. The BHG group received BHG twice a day for 3 months, and was followed-up for 6 months after treatment; the placebo group did not receive any Chinese Herb treatment for 9 months. All the patients were given the conventional therapy of levodopa (Madopar)., Main Outcome Measures: Primary outcome measure was PDQ-39 comprises 39 questions with five different options of answer related to the frequency of the disease manifestation., Results: Significant statistical difference appeared in the following PDQ-39 dimensions: mobility; emotional well-being; stigma; cognition (P<0.01) and bodily discomfort (P<0.05).There was no statistical difference in the dimensions of social support, ADL and communication between the data of these two group patients (P≥0.05). We found that the sum index of PDQ-39 was significantly different between two groups., Conclusion: The results of this study show that BHG treatment makes significant effects in most domains of PD patients life quality,especially in mobility, emotional well-being, stigma and cognition. The affected factors should be confirmed in larger studies., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Recently considerable researches have focused on monitoring vegetation changes because of its important role in regula- ting the terrestrial carbon cycle and the climate system. There were the largest areas with high-altitudes in the Qinghai-Tibet Plateau (QTP), which is often referred to as the third pole of the world. And vegetation in this region is significantly sensitive to the global warming. Meanwhile NDVI dataset was one of the most useful tools to monitor the vegetation activity with high spatial and temporal resolution, which is a normalized transform of the near-infrared radiation (NIR) to red reflectance ratio. Therefore, an extended GIMMS NDVI dataset from 1982-2006 to 1982-2014 was presented using a unary linear regression by MODIS dataset from 2000 to 2014 in QTP. Compared with previous researches, the accuracy of the extended NDVI dataset was improved again with consideration the residuals derived from scale transformation. So the model of extend NDVI dataset could be a new method to integrate different NDVI products. With the extended NDVI dataset, we found that in growing season there was a statistically significant increase (0.000 4 yr⁻¹, r² = 0.585 9, p < 0.001) in QTP from 1982 to 2014. During the study pe- riod, the trends of NDVI were significantly increased in spring (0.000 5 yr⁻¹, r² = 0.295 4, p = 0.001), summer (0.000 3 yr⁻¹, r² = 0.105 3, p = 0.065) and autumn respectively (0.000 6 yr⁻¹, r² = 0.436 7, p < 0.001). Due to the increased vegeta- tion activity in Qinghai-Tibet Plateau from 1982 to 2014, the magnitude of carbon sink was accumulated in this region also at this same period. Then the data of temperature and precipitation was used to explore the reason of vegetation changed. Although the trends of them are both increased, the correlation between NDVI and temperature is higher than precipitation in vegetation grow- ing season, spring, summer and autumn. Furthermore, there is significant spatial heterogeneity of the changing trends for ND- VI, temperature and precipitation at Qinghai-Tibet Plateau scale.

To understand the role of interferon (IFN)-γ gene (IFNG) single-nucleotide polymorphisms (SNPs) in the resistance to H5N1 highly pathogenic avian influenza (HPAI), we determined the SNPs, the log2-transformed specific antibody titers, and ex vivo recall antigen-specific IFN-γ production by peripheral blood mononuclear cells (PBMCs) in 62 red junglefowls (Gallus gallus) immunized twice with inactivated H5N1 HPAI vaccine. Consequently, 52 SNPs were detected in the amplified 1137-bp length covering the promoter region and all exons, with +2133A/T SNP in the coding DNA sequence that caused a missense mutation and was identified in G. gallus for the first time. For -316A/G SNP genotypes, the chi-squared test showed that the bird sample was in the Hardy-Weinberg equilibrium (P=0.369>0.05), and the least squares analysis revealed an increasing tendency in the antibody titers with G to A substitution so that a significant difference occurred between the AA genotype (8.031±0.247) and the GG genotype (6.571±0.528) (P=0.015<0.05, 95% confidence interval [CI]: 0.0004-0.0866), as basically consistent with the antigen-induced IFN-γ protein expression, which indicated possible association of the -316A/G SNP with a secondary humoral immune response to the HPAI vaccine in the bird population. These findings may help to improve genetic resistance using cross-breeding and enhance HPAI vaccine-induced immunity in chicken production.

Background/objectives: Lysosomal/autophagic pathway plays important role in the early onset of acute pancreatitis (AP). However, its role in the later recovery phase of AP is unknown. This study aims to investigate the role of lysosomal/autophagic pathway in the self-limited program of AP and elucidate the underlying mechanisms., Methods: AP was induced in the rat by 3% sodium taurocholate injection in the pancreaticobiliary duct. Serum amylase activity assay, histological examination, and cell death detection were used to assess the time course of AP severity. Meanwhile, the expression of LC3-II, p62 and Lamp-2 was measured to evaluate the status of autophagic flux. S6RP phosphorylation was detected to determine the time course of mTOR activation. Rapamycin was administered to block mTOR activity., Results: AP developed in the rats to the most severe at 24 h but tended to self-restore at 36 and 48 h. The impairment of autophagic flux characterized by the accumulation of LC3-II and p62 and the depletion of Lamp-2 occurred at 24 h after AP induction followed by the restoration over the following 24 h. Furthermore, the phosphorylation of S6RP was increased at 36 and 48 h after AP induction despite the initial inhibition. Rapamycin treatment reduced the level of phospho-S6RP and inhibited the restoration of autophagic homeostasis and pancreatic tissue injury., Conclusions: Activation of mTOR is correlated with the improvement of autophagic flux and pancreatic injury, suggesting that mTOR activation plays a potential protective role in the later recovery of AP., (Copyright © 2015 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

This study aims to investigate the anxiolytic effects of essential oil from S. miltiorrhiza in rats. The elevated plus maze test and the social interaction test were performed to evaluate the anxiolytic effects of essential oil. The levels of noradrenaline (NE), dopamine (DA) and serotonin (5-HT) in cerebral cortex of rats as well as the plasma corticosterone (CORT) level were examined in the rats with the treatment of essential oil. The rota-rod test was carried out to exclude any false positive results in experimental procedures related to anxiety disorders. The catalepsy test was carried out to investigate whether essential oil induces the catalepsy. Our results showed that oral administration of essential oil increased the percentage of time spent in the open arms and increased the number of entries to the open arms in the elevated plus maze test. Oral administration of essential oil also increased the time for social interaction in rats. No apparent extrapyramidal symptom (EPS) was observed in the animals with essential oil treatment. The effect of essential oil in the intracellular chloride (Cl(-)) concentration in the cultured human neuroblastoma cells was assessed. Treatment with essential oil (50-100 mg/kg) increased intracellular Cl(-) concentration in the cell culture in a dose-dependent manner, suggesting the involvement of GABAA receptor-Cl(-) ion channel. Together, our data indicate an anxiolytic effect induced by the essential oil from S. miltiorrhiza.

Arsenic trioxide (As2O3) has been shown to induce apoptosis in hepatocellular carcinoma cells. However, the molecular mechanism of As2O3-induced apoptosis in the hepatocellular carcinoma cells remains poorly understood. Here, we investigated the impact of As2O3 exposure on the human hepatocellular carcinoma cell line HepG2 and examined the underlying mechanism of cell death. As2O3 induced apoptosis of HepG2 cells in a dose- and time-dependent manner and caused a massive production of reactive oxygen species (ROS). The antioxidant N-acetylcysteine (NAC) was able to prevent As2O3-induced cell death, implying an involvement of ROS in the induction of As2O3-triggered apoptosis. Furthermore, As2O3 initiated apoptosis by triggering of the mitochondria apoptotic pathway as indicated by inhibited Bcl-2 expression, a collapse of the mitochondrial membrane potential (MMP), release of cytochrome c and activation of the caspase cascade. However, these As2O3-induced events can be prevented by NAC. Taken together, these findings suggest that the As2O3 induced apoptosis through a ROS-mediated mitochondrial pathway and activation of caspases.

Objective: To analyze the clinical evaluation of Parkinson's disease (PD) patients receiving integrated Chinese and Western medicine therapy., Methods: One hundred and twenty patients were enrolled and randomly allocated to a control group or treatment group. Patients in the two groups received placebo and Bushen Huoxue Granule (, BHG), respectively. Both groups received baseline levodopa and benserazide (Madopar). The effects of treatment were assessed monthly during the 9-month treatment. Means of evaluation included Unified PD Rating Scale (UPDRS) scores (II and III), sleep scale score, 10 m turn back test (getting up time, 10 m×2 times, and turning time), timing motor test (TMT)-left and TMT-right, which were treated as the dependent variables; and age, sex, duration of PD, Hoehn and Yahr (H-Y) stage and Madopar dosage of admitted PD patients were as the independent variables. Multiple linear regression was used to analyze these factors., Results: H-Y stage significantly affected UPDRS II score, UPDRS III score, and getting up time (P<0.01). Madopar dosage and H-Y stage significantly affected the 10 m×2 times (P<0.05 or <0.01). Madopar dosage significantly affected the sleep scale score (P<0.05). There were also significant correlations between age and TMT-left or TMT-right (P<0.01), and duration of PD and TMT-right (P<0.05)., Conclusions: The six assessed means of clinical evaluation (including UPDRS II and UPDRS III scores, sleep scale score, getting up time, 10 m×2 times, and turning time) are sensitive indexes in all PD patients. H-Y stage and Madopar dosage are the major factors influencing means of clinical assessment of PD treatment.

Background: The recently solved solution structure of HCV (hepatitis C virus) p7 ion channel provides a solid structure basis for drug design against HCV infection. In the p7 channel the ligand amantadine (or rimantadine) was determined in a hydrophobic pocket. However the pharmocophore (-NH2) of the ligand was not assigned a specific binding site., Results: The possible binding sites for amino group of adamantane derivatives is studied based on the NMR structure of p7 channel using QM calculation and molecular modeling. In the hydrophobic cavity and nearby three possible binding sites are proposed: His17, Phe20, and Trp21. The ligand binding energies at the three binding sites are studied using high level QM method CCSD(T)/6-311+G(d,p) and AutoDock calculations, and the interaction details are analyzed. The potential application of the binding sites for rational inhibitor design are discussed., Conclusions: Some useful viewpoints are concluded as follows. (1) The amino group (-NH2) of adamantane derivatives is protonated (-NH3+), and the positively charged cation may form cation-π interactions with aromatic amino acids. (2) The aromatic amino acids (His17, Phe20, and Trp21) are the possible binding sites for the protonated amino group (-NH3+) of adamantane derivatives, and the cation-π bond energies are 3 to 5 times stronger than the energies of common hydrogen bonds. (3) The higher inhibition potent of rimantadine than amantadine probably because of its higher pKa value (pKa = 10.40) and the higher positive charge in the amino group. The potential application of p7 channel structure for inhibitor design is discussed.

Background: Among the 20 natural amino acids histidine is the most active and versatile member that plays the multiple roles in protein interactions, often the key residue in enzyme catalytic reactions. A theoretical and comprehensive study on the structural features and interaction properties of histidine is certainly helpful., Results: Four interaction types of histidine are quantitatively calculated, including: (1) Cation-π interactions, in which the histidine acts as the aromatic π-motif in neutral form (His), or plays the cation role in protonated form (His+); (2) π-π stacking interactions between histidine and other aromatic amino acids; (3) Hydrogen-π interactions between histidine and other aromatic amino acids; (4) Coordinate interactions between histidine and metallic cations. The energies of π-π stacking interactions and hydrogen-π interactions are calculated using CCSD/6-31+G(d,p). The energies of cation-π interactions and coordinate interactions are calculated using B3LYP/6-31+G(d,p) method and adjusted by empirical method for dispersion energy., Conclusions: The coordinate interactions between histidine and metallic cations are the strongest one acting in broad range, followed by the cation-π, hydrogen-π, and π-π stacking interactions. When the histidine is in neutral form, the cation-π interactions are attractive; when it is protonated (His+), the interactions turn to repulsive. The two protonation forms (and pKa values) of histidine are reversibly switched by the attractive and repulsive cation-π interactions. In proteins the π-π stacking interaction between neutral histidine and aromatic amino acids (Phe, Tyr, Trp) are in the range from -3.0 to -4.0 kcal/mol, significantly larger than the van der Waals energies.

Oxidative stress is a pivotal pathogenic factor for bone loss in mouse model. Salidroside, a phenylpropanoid glycoside extracted from Rhodiola rosea L, exhibits potent antioxidative effects. In the present study, we used an in vitro oxidative stress model induced by hydrogen peroxide (H(2)O(2)) in MC3T3-E1 cells and a murine ovariectomized (OVX) osteoporosis model to investigate the protective effects of salidroside on bone loss and the related mechanisms. We demonstrated that salidroside caused a significant (P<0.05) elevation of cell survival, alkaline phosphatase (ALP) staining and activity, calcium deposition, and the transcriptional expression of Alp, Col1a1 and Osteocalcin (Ocn) in the presence of H(2)O(2). Moreover, salidroside decreased the production of intracellular reactive oxygen species (ROS), and osteoclast differentiation inducing factors such as receptor activator of nuclear factor-kB ligand (RANKL) and IL-6 induced by H(2)O(2). In vivo studies further demonstrated that salidroside supplementation for 3 months caused a decrease in malondialdehyde (MDA) and an increase in reduced glutathione (GSH) concentration in blood of ovariectomized mouse (P<0.05), it also improved trabecular bone microarchitecture and bone mineral density in the fourth lumbar vertebra and distal femur. Our study indicated that the protection provided by salidroside in alleviating bone loss was mediated, at least in part, via inhibition of the release of bone-resorbing mediators and oxidative damage to bone-forming cells, suggesting that salidroside can be used as an effective remedy in the treatment or prevention of osteoporosis.

Clinical and experimental data have demonstrated that inflammation plays fundamental roles in the pathogenesis of ischemic stroke. Interleukin-16 (IL-16) is identified as a proinflammatory cytokine that is a key element in the ischemic cascade after cerebral ischemia. We aimed to examine the relationship between the IL-16 polymorphisms and the risk of ischemic stroke in a Chinese population. A total of 198 patients with ischemic stroke and 236 controls were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing method. We found that the rs11556218TG genotype and G allele of IL-16 were associated with significantly increased risks of ischemic stroke (TG versus TT, adjusted OR = 1.88; 95% CI, 1.15-3.07; G versus T, adjusted OR = 1.54; 95% CI, 1.05-2.27, resp.). However, there were no significant differences in the genotype and allele frequencies of IL-16 rs4778889 T/C and rs4072111 C/T polymorphisms between the two groups, even after stratification analyses by age, gender, and the presence or absence of hypertension, diabetes mellitus, hypercholesterolemia, and hypertriglyceridemia. These findings indicate that the IL-16 polymorphism may be related to the etiology of ischemic stroke in the Chinese population.

Oxidative stress can induce apoptosis and decrease activities of osteoblasts. 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (TSG), is a potent antioxidant derived from a Chinese herb Polygonum multiflorum Thunb. To evaluate the protective effect provided by TSG to osteoblastic MC3T3-E1 cells, the cells were pretreated with TSG for 24h before being treated with 0.3mM hydrogen peroxide (H(2)O(2)) for 24 h, then some markers of osteoblast function and oxidative damage of the cells were examined. Our data demonstrated that TSG significantly (P< 0.05) increased cell survival, alkaline phosphatase (ALP) activity, calcium deposition, and the mRNA expression of ALP, collagen I (COL-I) and osteocalcin (OCN) in the presence of H(2)O(2). In addition, TSG decreased the production of receptor activator of nuclear factor-κB ligand (RANKL), interleukin-6 (IL-6), intracellular reactive oxygen species and malondialdehyde (MDA) of osteoblastic MC3T3-E1 cells induced by H(2)O(2). Taken together, these results demonstrated that the protective effect provided by TSG to osteoblastic MC3T3-E1 cells was mediated, at least in part, via inhibition of the release of bone-resorbing mediators and oxidative damage of the cells. Our results indicated that TSG may be effective in providing protection against osteoporosis associated with oxidative stress., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Statistical effective energy function (SEEF) is derived from the statistical analysis of the database of known protein structures. Dehouck-Gilis-Rooman (DGR) group has recently created a new generation of SEEF in which the additivity of the energy terms was manifested by decomposing the total folding free energy into a sum of lower order terms. We have tried to optimize the potential function based on their work. By using decoy datasets as screening filter, and through modification of algorithms in calculation of accessible surface area and residue-residue interaction cutoff, four new combinations of the energy terms were found to be comparable to DGR potential in performance test. Most importantly, the term number was reduced from the original 30 terms to only 5 in our results, thereby substantially decreasing the computation time while the performance was not sacrificed. Our results further proved the additivity and manipulability of the DGR original energy function, and our new combination of the energy could be used in prediction of protein structures.

The cation-π interactions occur frequently within or between proteins due to six (Phe, Tyr, Trp, Arg, Lys, and His) of the twenty natural amino acids potentially interacting with metallic cations via these interactions. In this study, quantum chemical calculations and molecular orbital (MO) theory are used to study the energies and properties of cation-π interactions in biological structures. The cation-π interactions of H⁺ and Li⁺ are similar to hydrogen bonds and lithium bonds, respectively, in which the small, naked cations H⁺ and Li⁺ are buried deep within the π-electron density of aromatic molecules, forming stable cation-π bonds that are much stronger than the cation-π interactions of other alkali metal cations. The cation-π interactions of metallic cations with atomic masses greater than that of Li⁺ arise mainly from the coordinate bond comprising empty valence atomic orbitals (AOs) of metallic cations and π-MOs of aromatic molecules, though electrostatic interactions may also contribute to the cation-π interaction. The binding strength of cation-π interactions is determined by the charge and types of AOs in the metallic cations. Cation-π interaction energies are distance- and orientation-dependent; energies decrease with the distance (r) and the orientation angle (θ). In solution, the cation-π energies decrease with the increase of the dielectric constant (ɛ) of the solvent; however, solvation has less influence on the H⁺-π and H₃O⁺-π interactions than on interactions with other cations. The conclusions from this study provide useful theoretical insights into the nature of cation-π interactions and may contribute to the development of better force field parameters for describing the molecular dynamics of cation-π interactions within and between proteins., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Cation-π interaction is comparable and as important as other main molecular interaction types, such as hydrogen bond, electrostatic interaction, van der Waals interaction, and hydrophobic interaction. Cation-π interactions frequently occur in protein structures, because six (Phe, Tyr, Trp, Arg, Lys, and His) of 20 natural amino acids and all metallic cations could be involved in cation-π interaction. Cation-π interactions arise from complex physicochemical nature and possess unique interaction behaviors, which cannot be modeled and evaluated by existing empirical equations and force field parameters that are widely used in the molecular dynamics. In this study, the authors present an empirical approach for cation-π interaction energy calculations in protein interactions. The accurate cation-π interaction energies of aromatic amino acids (Phe, Tyr, and Try) with protonated amino acids (Arg and Lys) and metallic cations (Li(+), Na(+), K(+), and Ca(2+)) are calculated using B3LYP/6-311+G(d,p) method as the benchmark for the empirical formulization and parameterization. Then, the empirical equations are built and the parameters are optimized based on the benchmark calculations. The cation-π interactions are distance and orientation dependent. Correspondingly, the empirical equations of cation-π interactions are functions of two variables, the distance r and the orientation angle θ. Two types of empirical equations of cation-π interactions are proposed. One is a modified distance and orientation dependent Lennard-Jones equation. The second is a polynomial function of two variables r and θ. The amino acid-based empirical equations and parameters provide simple and useful tools for evaluations of cation-π interaction energies in protein interactions., (Copyright © 2011 Wiley Periodicals, Inc.)

Background: The proteins in a family, which perform the similar biological functions, may have very different amino acid composition, but they must share the similar 3D structures, and keep a stable central region. In the conservative structure region similar biological functions are performed by two or three catalytic residues with the collaboration of several functional residues at key positions. Communication signals are conducted in a position network, adjusting the biological functions in the protein family., Methodology: A computational approach, namely structural position correlation analysis (SPCA), is developed to analyze the correlation relationship between structural segments (or positions). The basic hypothesis of SPCA is that in a protein family the structural conservation is more important than the sequence conservation, and the local structural changes may contain information of biology functional evolution. A standard protein P(0) is defined in a protein family, which consists of the most-frequent amino acids and takes the average structure of the protein family. The foundational variables of SPCA is the structural position displacements between the standard protein P(0) and individual proteins P(i) of the family. The structural positions are organized as segments, which are the stable units in structural displacements of the protein family. The biological function differences of protein members are determined by the position structural displacements of individual protein P(i) to the standard protein P(0). Correlation analysis is used to analyze the communication network among segments., Conclusions: The structural position correlation analysis (SPCA) is able to find the correlation relationship among the structural segments (or positions) in a protein family, which cannot be detected by the amino acid sequence and frequency-based methods. The functional communication network among the structural segments (or positions) in protein family, revealed by SPCA approach, well illustrate the distantly allosteric interactions, and contains valuable information for protein engineering study.

Background: The main clinical symptoms of Parkinson's disease (PD) are resting tremor, muscle rigidity, bradykinesia, and so on. There is no effective treatment for PD yet, and dyskinesia symptoms affect the life qualities of PD patients. The therapy used for reinforcing kidney and activating blood circulation in treatment of PD can achieve good clinical effects., Objective: To evaluate the efficacy and safety of Bushen Huoxue Granule (BSHXG), a compound traditional Chinese herbal medicine for reinforcing kidney and activating blood circulation in treatment of PD., Design, Setting, Participants and Interventions: A multi-center, randomized, double-blind, placebo-controlled clinical study was undertaken. A total of 120 PD patients from Outpatient Department of General Hospital of People's Liberation Army, Guangdong Provincial Hospital of Traditional Chinese Medicine, and Xijing Hospital and Tangdu Hospital in Xi'an, were randomly divided into BSHXG group and placebo group. There were 55 cases in BSHXG group, for 5 cases lost to follow-up, and 51 cases in placebo group, for 1 case was excluded and 8 cases lost to follow-up. The patients in two groups were all treated for three months., Main Outcome Measures: The movement scale, exercise testing, and muscle tension were observed before and after treatment to make a comprehensive evaluation for clinical efficacy. One month follow-up was also made., Results: At three different times (one, two and three months) after treatment, the score of Unified Parkinson's Disease Rating Scale (UPDRS) III, rise time of 10-meter back and forth exercise and resting muscle tension in BSHXG group were improved as compared with before treatment (P<0.05, P<0.01), and there was an interaction between treatment time and intervention (P<0.05, P<0.01). There were no differences in evaluation results of chronograph movement (times of left and right hand movement in one minute), and walking time and turn around time of 10-meter back and forth exercise between BSHXG group and placebo group, and no interaction existed between treatment time and intervention. BSHXG showed a better efficacy than the placebo (P<0.01) in improving motor function, shortening rise time of 10-meter back and forth test and relieving muscle tension. No adverse effects were found in this trial., Conclusion: BSHXG plus Western medicine is effective and safe in improving motor dysfunction of PD patients.

Green tea, owing to its beneficial effect on health, is becoming more and more popular worldwide. (-)-Epigallocatechin-3-gallate (EGCG), the main ingredient of green tea polyphenols, is a known protective effect on injured neurons in neurodegenerative disease, such as Alzheimer's disease and Parkinson's disease. Paraquat (PQ) is a widely used herbicide that possesses a similar structure to MPP(+) and is toxic to mesencephalic dopaminergic neurons. In the present study, PQ-injured PC12 cells were chosen as an in vitro cell model of Parkinson's disease and the neuroprotective effects of EGCG were investigated. The results showed that EGCG attenuated apoptosis of PC12 cells induced by PQ. The possible mechanism may be associated with maintaining mitochondrial membrane potential, inhibiting caspase-3 activity and downregulating the expression of pro-apoptotic protein Smac in cytosol. The present study supports the notion that EGCG could be used as a neuroprotective agent for treatment of neurodegenerative diseases.

Objective: To investigate the safety dosage of intravitreal injection of Plasmin, Hyaluronidase and their combination and to evaluate their efficacy in the formation of posterior vitreous detachment (PVD) through animal experiments., Methods: Eight rabbits each were randomly assigned to one of six groups and one eye of each rabbit were experimental eye, the other is control eye. The position of drug injection was in posterior 1/3 of vitreous before papillary. The drug-injection groups were assigned as following: the first group-Hyaluronidase 20 IU (0.1 ml BSS), the second group-Hyaluronidase 30 IU (0.1 ml BSS), the third group-Plasmin 1 IU (0.1 ml BSS), the forth group-Plasmin 2 IU (0.1 ml BSS), the fifth group-Plasmin 3 IU (0.1 ml BSS), the sixth group- Hyaluronidase 20 IU (0.05 ml BSS) combined with Plasmin 1 IU (0.05 ml BSS); the control eyes were injected with BSS (0.1 ml) at the same position. The experimental rabbits were followed for 2 weeks, and in this period all eyes were examined with slit-lamp biomicroscopy, +90 D preset lens, indirect ophthalmoscope, electroretinography, B-scan, and optical coherence tomography. After two weeks, the animals were killed and the eyes enucleated. Scan electron and light microscopy were performed., Results: Hyaluronidase concentration of 20 IU, Plasmin concentration of 1 IU and their combination didn't produce inflammatory response and retinal toxicity in the experimental eyes. 30 IU Hyaluronidase and 2 IU Plasmin both caused mild inflammatory response in the vitreous without retinal histological changes, while the latter caused a reversible decrease in the ERG b-wave. 3 IU of Plasmin caused severe inflammatory response with retinal histological and electroretinographic changes. In safety dosage neither Hyaluronidase nor Plasmin alone were successful in producing completely posterior vitreous detachment (PVD), but the latter can produce partial PVD. The combination of Plasmin (1 IU) and Hyaluronidase (20 IU) was effective on producing completely PVD without retinal toxicity., Conclusion: 20 IU of Hyaluronidase and 1 IU of Plasmin are safe to retina and others structures in the eyes without any toxicity. Posterior vitreous injection of Hyaluronidase (20 IU) combined with Plasmin (1 IU) can produce complete posterior vitreous detachment.

OBJECTIVE: To establish a simple, sensitive in vitro method to evaluate oxygen/glucose deprivation (OGD)-induced injury of brain hippocampal slices in rats. METHODS: Rat hippocampal slices were incubated in 2% 2, 3, 5-triphenyltetrazolium chloride (TTC) solution after oxygen/glucose deprivation. They were then soaked in a measured volume of ethanol and dimethylsulfoxide (50:50) to extract the TTC formazan Product which was then measured by spectrophotometry. OGD induced LDH release was simultaneously measured. RESULTS: Progressive prolongation of OGD induced hippocampal injury resulted in decreased formazan coloration as determined by spectrophotometry. There was a parallel increase in LDH release, thus a negative correlation in these two products was noted. (r=-0.933,P <0.01). The injury was attenuated in the brain slices pre-treated with nimodipine, dexamethasone, and ketamine, but not ONO-1078. CONCLUSION: Solvent extraction and spectrophotometric quantification of formazan represents an objective measurement of OGD-induced injury of rat hippocampal slices.