The two-step strategy for enhancing the specific activity and thermostability of alginate lyase AlyG2 with mechanism for improved thermostability.

To overcome the trade-off challenge encountered in the engineering of alginate lyase AlyG2 from Seonamhaeicola algicola Gy8T and to expand its potential industrial applications, we devised a two-step strategy encompassing activity enhancement followed by thermal stability engineering. To enhance the specific activity of efficient AlyG2, we strategically substituted residues with bulky steric hindrance proximal to the active pocket with glycine or alanine. This led to the generation of three promising positive mutants, with particular emphasis on the T91S mutant, exhibiting a 1.91-fold specific activity compared to the wild type. To mitigate the poor thermal stability of T91S, mutants with negative ΔΔG values in the thermal flexibility region were screened out. Notably, the S72Ya mutant not only displayed 17.96 % further increase in specific activity but also exhibited improved stability compared to T91S, manifesting as a remarkable 30.97 % increase in relative activity following a 1-hour incubation at 42 °C. Furthermore, enhanced kinetic stability was observed. To gain deeper insights into the mechanism underlying the enhanced thermostability of the S72Ya mutant, we conducted molecular dynamics simulations, principal component analysis (PCA), dynamic cross-correlation map (DCCM), and free energy landscape (FEL) analysis. The results unveiled a reduction in the flexibility of the surface loop, a stronger correlation dynamic and a narrower motion subspace in S72Ya system, along with the formation of more stable hydrogen bonds. Collectively, our findings suggest amino acids substitutions resulting in smaller side chains proximate to the active site can positively impact enzyme activity, while reducing the flexibility of surface loops emerges as a pivotal factor in conferring thermal stability. These insights offer valuable guidance and a framework for the engineering of other enzyme types.

Silver Nanoparticles Encapped by Dihydromyricetin: Optimization of Green Synthesis, Characterization, Toxicity, and Anti-MRSA Infection Activities for Zebrafish (Danio rerio).

To achieve the environmentally friendly and rapid green synthesis of efficient and stable AgNPs for drug-resistant bacterial infection, this study optimized the green synthesis process of silver nanoparticles (AgNPs) using Dihydromyricetin (DMY). Then, we assessed the impact of AgNPs on zebrafish embryo development, as well as their therapeutic efficacy on zebrafish infected with Methicillin-resistant Staphylococcus aureus (MRSA). Transmission electron microscopy (TEM) and dynamic light-scattering (DLS) analyses revealed that AgNPs possessed an average size of 23.6 nm, a polymer dispersity index (PDI) of 0.197 ± 0.0196, and a zeta potential of -18.1 ± 1.18 mV. Compared to other published green synthesis products, the optimized DMY-AgNPs exhibited smaller sizes, narrower size distributions, and enhanced stability. Furthermore, the minimum concentration of DMY-AgNPs required to affect zebrafish hatching and survival was determined to be 25.0 µg/mL, indicating the low toxicity of DMY-AgNPs. Following a 5-day feeding regimen with DMY-AgNP-containing food, significant improvements were observed in the recovery of the gills, intestines, and livers in MRSA-infected zebrafish. These results suggested that optimized DMY-AgNPs hold promise for application in aquacultures and offer potential for further clinical use against drug-resistant bacteria.

Preliminary identification and semi-quantitative characterization of a multi-faceted high-stability alginate lyase from marine microbe Seonamhaeicola algicola with anti-biofilm effect on Pseudomonas aeruginosa.

Alginate lyases with unique characteristics for degrading alginate into size-defined oligosaccharide fractions, were considered as the potential agents for disrupting Pseudomonas aeruginosa biofilms. In our study, a novel endolytic PL-7 alginate lyase, named AlyG2, was cloned and expressed through Escherichia coli. This enzyme exhibited excellent properties: it maintained more than 85% activity at low temperatures of 4 °C and high temperatures of 70 °C. After 1 h of incubation at 4 °C, it still retained over 95% activity, demonstrating the ability to withstand low temperature. The acid-base and salt tolerance properties shown it preserves more than 50% activity in the pH range of 5.0 to 11.0 and in a high salt environment at 3000 mM NacCl, indicating its high stability in several aspects. More importantly, AlyG2 in our research was revealed to be effective at removing mature biofilms and inhibiting biofilm formation produced by Pseudomonas aeruginosa, and the inhibition and disruption rates were 47.25 ± 4.52% and 26.5 ± 6.72%, respectively. Additionally, the enzyme AlyG2 promoted biofilm disruption in combination with antibiotics, particularly manifesting the synergistic effect with erythromycin (FIC=0.5). In all, these results offered that AlyG2 with unique characteristics may be an effective technique for the clearance or disruption of biofilm produced by P. aeruginosa.

Dysbiosis of gut microbiota and metabolites during AIDS: implications for CD4 + T cell reduction and immune activation.

OBJECTIVE: Identifying the gut microbiota associated with host immunity in the AIDS stage. DESIGN: We performed a cross-sectional study. METHODS: We recruited people with HIV (PWH) in the AIDS or non-AIDS stage and evaluated their gut microbiota and metabolites by using 16S ribosomal RNA (rRNA) sequencing and liquid chromatography-mass spectrometry (LC-MS). Machine learning models were used to analyze the correlations between key bacteria and CD4 + T cell count, CD4 + T cell activation, bacterial translocation, gut metabolites, and KEGG functional pathways. RESULTS: We recruited 114 PWH in the AIDS stage and 203 PWH in the non-AIDS stage. The α-diversity of gut microbiota was downregulated in the AIDS stage ( P  < 0.05). Several machine learning models could be used to identify key gut microbiota associated with AIDS, including the logistic regression model with area under the curve (AUC), sensitivity, specificity, and Brier scores of 0.854, 0.813, 0.813, and 0.160, respectively. The decreased key bacteria ASV1 ( Bacteroides sp.), ASV8 ( Fusobacterium sp.), ASV30 ( Roseburia sp.), ASV37 ( Bacteroides sp.), and ASV41 ( Lactobacillus sp.) in the AIDS stage were positively correlated with the CD4 + T cell count, the EndoCAb IgM level, 4-hydroxyphenylpyruvic acid abundance, and the predicted cell growth pathway, and negatively correlated with the CD3 + CD4 + CD38 + HLA-DR + T cell count and the sCD14 level. CONCLUSION: Machine learning has the potential to recognize key gut microbiota related to AIDS. The key five bacteria in the AIDS stage and their metabolites might be related to CD4 + T cell reduction and immune activation.

The median effective dose of propofol combined with butorphanol during artificial abortion: a randomized controlled trial.

Objective: Propofol-opioids are the most common drug combination and can reduce the dose of propofol and the incidence of adverse events in painless artificial abortion. We hypothesized that butorphanol may reduce the median effective dose (ED50) of propofol, propofol injection pain, and postoperative uterine contraction pain. Methods: This was a randomized, double-blind, controlled study. A total of 54 female patients, who had ASA I or II, aged 18-49 years, undergoing painless artificial abortion, were randomly assigned into two groups, namely, Group P (propofol) and Group PB (propofol plus 10 µg/kg butorphanol). According to the pre-experiment, the initial dose of propofol for the P and PB groups was 3 and 2.5 mg/kg, respectively, with a dose gradient of 0.25 mg/kg. The ED50 of propofol was analyzed using probit regression analysis. The total propofol dose consumed, recovery time, and anesthesia-related adverse events were also recorded. Results: There were 25 and 29 patients in the P and PB groups, respectively. The ED50 (95% CI) of propofol for artificial abortion were 2.477 (2.186-2.737) and 1.555 (1.173-1.846) mg/kg in the P and PB groups, respectively. The total propofol dose consumed was (150.7 ± 21.7) mg and (110.4 ± 28.2) mg in the P and PB groups, respectively (P < 0.001). Compared with the P group, injection-site pain (76 vs. 20.7%) and uterine contraction pain (72 vs. 6.9%) in the PB group had a significant decrease (P < 0.001). Conclusion: Combination of propofol with 10 µg/kg butorphanol reduced the ED50 of propofol and decreased the incidence of propofol injection-site pain and postoperative uterine contraction pain during painless artificial abortion compared with propofol alone. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=166610, identifier: ChiCTR2200059795.

Preparation of Tetrandrine Nanocrystals by Microfluidic Method and Its In Vitro and In Vivo Evaluation.

The anti-hepatocellular carcinoma effects of TET are acknowledged, but its application is hindered by its poor water solubility and low bioavailability. Conventional methods for nanocrystal preparation are laborious and lack control. To address these limitations, we propose employing the microfluidic method in the preparation of TET nanocrystals, aiming to enhance the aforementioned constraints. The objectives of this study were to prepare TET nanocrystals (TET-NC@GL) using a Y-microfluidic method with glycyrrhetinic acid (GL) as a stabilizer. The optimal preparation prescription was determined through a single-factor test and Box-Behnken response surface method. Additionally, the nanocrystals prepared with the commonly used stabilizer polyvinylpyrrolidone K30 (PVPK30), known as TET-NC@PVPK30, were characterized and evaluated for their toxicity to HepG2 cells. Hybridized nanocrystals (TET-HNC@GL and TET-HNC@PVPK30) were synthesized using a water-soluble aggregation-induced emission (AIE) fluorescent probe (TVP). Qualitative and quantitative cellular uptake experiments were conducted using these hybridized nanocrystals. Conducting in vivo pharmacokinetic assays evaluates the relative bioavailability of nanocrystals. The results indicated that TET-NC@GL, optimized using the response surface method, had a particle size of 136.47 ± 3.31 nm and a PDI of 0.219 ± 0.002. The administration of TET-NC@GL significantly enhanced the cell inhibition rate compared to the TET group and the TET-NC@PVPK30 group (P < 0.01). Moreover, the qualitative and quantitative cellular uptake results revealed a significant enhancement in cellular uptake in the TET-HNC@GL administration group compared to the TET-HNC@PVPK30 group (P < 0.01). In vivo pharmacokinetic results showed that the bioavailability of TET-NC@GL group was 3.5 times higher than that of the TET group. The results demonstrate the successful preparation of TET-NC@GL nanocrystals.

Single-cell RNA sequencing revealed potential targets for immunotherapy studies in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a solid tumor prone to chemotherapy resistance, and combined immunotherapy is expected to bring a breakthrough in HCC treatment. However, the tumor and tumor microenvironment (TME) of HCC is highly complex and heterogeneous, and there are still many unknowns regarding tumor cell stemness and metabolic reprogramming in HCC. In this study, we combined single-cell RNA sequencing data from 27 HCC tumor tissues and 4 adjacent non-tumor tissues, and bulk RNA sequencing data from 374 of the Cancer Genome Atlas (TCGA)-liver hepatocellular carcinoma (LIHC) samples to construct a global single-cell landscape atlas of HCC. We analyzed the enrichment of signaling pathways of different cells in HCC, and identified the developmental trajectories of cell subpopulations in the TME using pseudotime analysis. Subsequently, we performed transcription factors regulating different subpopulations and gene regulatory network analysis, respectively. In addition, we estimated the stemness index of tumor cells and analyzed the intercellular communication between tumors and key TME cell clusters. We identified novel HCC cell clusters that specifically express HP (HCC_HP), which may lead to higher tumor differentiation and tumor heterogeneity. In addition, we found that the HP gene expression-positive neutrophil cluster (Neu_AIF1) had extensive and strong intercellular communication with HCC cells, tumor endothelial cells (TEC) and cancer-associated fibroblasts (CAF), suggesting that clearance of this new cluster may inhibit HCC progression. Furthermore, ErbB signaling pathway and GnRH signaling pathway were found to be upregulated in almost all HCC tumor-associated stromal cells and immune cells, except NKT cells. Moreover, the high intercellular communication between HCC and HSPA1-positive TME cells suggests that the immune microenvironment may be reprogrammed. In summary, our present study depicted the single-cell landscape heterogeneity of human HCC, identified new cell clusters in tumor cells and neutrophils with potential implications for immunotherapy research, discovered complex intercellular communication between tumor cells and TME cells.

[ZEB2 Regulates the Migration and Invasion of PANC-1 Pancreatic Cancer Cells: An Experimental Study].

Objective: To investigate the effects and mechanisms of zinc finger E-box binding homeobox transcription factor-2 ( ZEB2) on the proliferation, colony formation, migration, and invasion abilities and the epithelial-mesenchymal transition (EMT) of PANC-1 cells, a human pancreatic cancer cell line. Methods: Data on the expression of ZEB2 in pancreatic cancer tissues and paracancerous tissues from The Cancer Genome Atlas (TCGA) database were analyzed. PANC-1 pancreatic cancer cells were divided into si-NC group, si- ZEB2 group, pcDNA3.1 group, and pcDNA3.1- ZEB2 group. qRT-PCR and Western blot were conducted to confirm the effectiveness of ZEB2 knockdown or overexpression. CCK-8, colony formation, wound healing, and Transwell assays were conducted to examine the effects of ZEB2 on the proliferation, colony formation, migration, and invasion of PANC-1 cells. qRT-PCR and immunofluorescence assays were performed to examine the expression of E-cadherin and vimentin, the EMT markers, in the cells. Prediction of proteins interacting with ZEB2 was made through the STRING database. Results: TCGA database analysis showed that the expression level of ZEB2 in pancreatic cancer tissues was significantly higher than that in adjacent tissues ( P<0.05). Compared with those of cells in the control group, the proliferation, colony formation, migration, and invasion of cells in the si- ZEB2 group were decreased ( P<0.05). Compared with those of cells in the pcDNA3.1 group, the proliferation, colony formation, migration and invasion of cells in the pcDNA3.1- ZEB2 group were increased (all P<0.05). According to the results of qRT-PCR and immunofluorescence assays, compared with those of the si-NC group, the expression of E-cadherin mRNA, an epithelial marker, in the si- ZEB2 group increased, while the expression of vimentin mRNA, an mesenchymal marker, and the protein decreased. Compared with those of the pcDNA3.1 group, the expression of E-cadherin mRNA in the PANC-1 cells of the pcDNA3.1- ZEB2 group decreased, while the expression of vimentin mRNA and the protein increased (all P<0.05). Analysis with the STRING database predicted that 10 proteins had close interaction with ZEB2. Conclusion: Overexpression of ZEB2 promotes the migration, invasion, and the EMT process of PANC-1 pancreatic cancer cells.

Controllable 3D Flower-Like Ag-CF Electrodes as Flexible Marine Electric Field Sensors with High Stability.

Construction of three-dimensional (3D) flower-like nanostructures with controlled morphologies has emerged as an attractive tool by scientists in the marine electric field sensor research field due to their peculiar structural features. Herein, novel 3D flower-like Ag-CF capacitive composite electrodes have been created by an eco-friendly water-bath strategy via AgNO3 as a sliver source and subsequently compounded with carbon fibers (CFs) pretreated by thermal oxidation. A series of electrode samples with various morphologies obtained by modulating different reaction times and temperatures bring about the dominant formation mechanism of these nanostructures and the influence behavior on the CF electrode in detail. Especially, the 3D flower-like Ag-CF electrode shows a large surface area acquired under the conditions of 80 °C and 15 min, which can provide more electroactive sites in electrochemical analysis and exhibit a maximum areal specific capacitance of 619.75 mF·cm-2 at a scanning speed of 10 mV·s-1. This is mainly due to the synergistic behavior of the unique 3D flower-like morphology and the large specific surface area of CFs. Furthermore, a cylinder-shaped Ag-CF sensor is designed, which delivers a superior potential difference of 33.08 µV, a potential difference drift of 18.62 µV/24 h for 30 days, and a self-noise of 0.92 nV/rt (Hz)@1 Hz. In this work, the intriguing synthesis strategy can be a promising facile approach to manufacture the controllable 3D flower-like Ag-CF electrode for electric field sensor applications.

Changes in stigma characteristics of HIV infectionAIDS patients treated with antiviral therapy in Guangxi / 中国热带医学

@#Abstract: Objective To explore the dynamic characteristics of stigmatization in HIV/AIDS patients and provide scientific evidence for psychological care. Methods HIV/AIDS patients receiving antiretroviral therapy (ART) treatment in Nanning Fourth People's Hospital were randomly selected for baseline and 1 year follow-up questionnaire survey including internalized HIV stigma, anticipated HIV stigma, exposure to HIV stigma. The differences between the two groups at different time points were dynamically compared to analyze the changing characteristics of stigma in HIV/AIDS patients. Results After one year of ART treatment, among the eight items of internalizing stigma, five items including the proportion of feeling ashamed of being infected with HIV/AIDS, feeling unclean because of being infected with HIV/AIDS, feeling inferior to others because of having HIV/AIDS, feeling guilty because of having HIV/AIDS, and having a poorer self-perception due to how others view HIV/AIDS decreased significantly from 34.0% to 43.5% at the baseline to 19.5% to 29.5%, showing significant improvement with statistical significance (χ2=18.586, 14.277, 10.473, 12.219, 9.934, P<0.05); among the nine items of anticipated stigma, four items including the proportion of community/community workers not taking my needs seriously, discriminating against me, refusing to provide services for me, and healthcare workers avoiding contact with me decreased significantly from 16.0% to 27.5% at the baseline to 7.0% to 15.5%, respectively, showing significant improvement with statistical significance (χ2=13.690, 15.787, 12.034, 12.593, P<0.05); among the 16 items of exposure to HIV stigma, six items including the proportion of experiencing physical attacks, psychological pressure from spouses/partners, being refused sexual relationships, losing jobs or other economic sources, being rejected or losing a job opportunity due to HIV/AIDS, changing job nature due to HIV/AIDS, or being refused medical services decreased significantly from 2.5% to 15.0% at the baseline to 1.0% to 8.0%, respectively, showing significant improvement with statistical significance (χ2=8.619, 15.558, 6.061, 9.049, 5.432, 8.156, P<0.05). Physical assaults on people with HIV/AIDS increased by 5.5 percent(χ2=5.368, P<0.05). Conclusions Through 1-year dynamic monitoring, 48.48% of the three dimensions of stigma of HIV/AIDS patients were alleviated. Treatment intervention, self-acceptance and the creation of a good non-discriminatory social environment have an important impact on the stigma of HIV/AIDS patients and deserve the attention of society as a whole.

tBHQ attenuates podocyte injury in diabetic nephropathy by inhibiting NADPH oxidase-derived ROS generation via the Nrf2/HO-1 signalling pathway.

Aims: Oxidative stress plays a crucial role in podocyte injury in diabetic nephropathy (DN). tert-Butylhydroquinone (tBHQ) is an activator of Nrf2 that exerts protective effects in diabetic mice, but the underlying mechanism of tBHQ in the podocytes of DN is not fully understood. Materials and methods: A high glucose (HG)-induced HK2 cell model and streptozotocin-induced rat model of DN were established and treated with tBHQ or apocynin. The expression levels of Nrf2, HO-1, NOX2 and NOX4 were determined by Western blot or immunohistochemical staining. The level of oxidative stress in podocytes or kidney tissues was assessed using DCFH-DA or dihydroethidium (DHE) staining. Cell injury was assessed by F-actin staining and flow cytometry analysis. Key findings: We showed that HG treatment increased the expressions of NOX2 and NOX4 and enhanced ROS production in podocytes. Inhibition of NADPH oxidase activity by apocynin dramatically attenuated HG-induced ROS production and further alleviated cell injury and apoptosis in podocytes. Moreover, we found that HG inhibited the Nrf2/HO-1 signalling pathway in podocytes; however, tBHQ treatment significantly activated the Nrf2 signalling pathway, inhibited NADPH oxidase activity, and attenuated ROS production and cell injury in HG-treated podocytes. Furthermore, we observed that tBHQ treatment partially attenuated renal injury, activated the Nrf2 signalling pathway, inhibited NADPH oxidase activity and reduced ROS generation in the kidneys of STZ-induced diabetic rats. Significance: These results suggest that tBHQ exerts a protective role in hyperglycaemia-induced podocyte injury, and that the potential protective mechanism of tBHQ involves inhibiting NADPH oxidase-derived ROS generation by activating the Nrf2/HO-1 signalling pathway.

Urethane Improves the Response of Auditory Neurons to Tone.

Urethane has little effect on nervous system and is often used in neuroscience studies. However, the effect of urethane in neurons is not thoroughly clear. In this study, we investigated changes in neuron responses to tones in inferior colliculus during urethane anesthesia. As urethane was metabolized, the best and characteristic frequencies did not obviously change, but the minimal threshold (MT) remained relatively stable or was elevated. The frequency tuning bandwidth at 60 dB SPL (BW60dBSPL) remained unchanged or decreased, and the average evoked spike of effective frequencies at 60 dB SPL (ES60dBSPL) gradually decreased. Although the average evoked spike of effective frequencies at a tone intensity of 20 dB SPL above MT (ES20dBSPLaboveMT) decreased, the frequency tuning bandwidth at a tone intensity of 20 dB SPL above MT (BW20dBSPLaboveMT) did not change. In addition, the changes in MT, ES60dBSPL, BW60dBSPL, and ES20dBSPLaboveMT increased with the MT in pre-anesthesia awake state (MTpre-anesthesiaawake). In some neurons, the MT was lower, BW60dBSPL was broader, and ES60dBSPL and ES20dBSPLaboveMT were higher in urethane anesthesia state than in pre-anesthesia awake state. During anesthesia, the inhibitory effect of urethane reduced the ES20dBSPLaboveMT, but did not change the MT, characteristic frequency, or BW20dBSPLaboveMT. In the recording session with the strongest neuron response, the first spike latency did not decrease, and the spontaneous spike did not increase. Therefore, we conclude that urethane can reduce/not change the MT, increase the evoked spike, or broaden/not change the frequency tuning range, and eventually improve the response of auditory neurons to tone with or without "pushing down" the tonal receptive field in thresholding model. The improved effect increases with the MTpre-anesthesiaawake of neurons. The changes induced by the inhibitory and improved effects of urethane abide by similar regularities, but the change directions are contrary. The improvement mechanism may be likely due to the increase in the ratio of excitatory/inhibitory postsynaptic inputs to neurons.

ClC-c regulates the proliferation of intestinal stem cells via the EGFR signalling pathway in Drosophila.

OBJECTIVES: Adult stem cells uphold a delicate balance between quiescent and active states, which is crucial for tissue homeostasis. Whereas many signalling pathways that regulate epithelial stem cells have been reported, many regulators remain unidentified. MATERIALS AND METHODS: Flies were used to generate tissue-specific gene knockdown and gene knockout. qRT-PCR was used to assess the relative mRNA levels. Immunofluorescence was used to determine protein localization and expression patterns. Clonal analyses were used to observe the phenotype. RNA-seq was used to screen downstream mechanisms. RESULTS: Here, we report a member of the chloride channel family, ClC-c, which is specifically expressed in Drosophila intestinal stem/progenitor cells and regulates intestinal stem cell (ISC) proliferation under physiological conditions and upon tissue damage. Mechanistically, we found that the ISC loss induced by the depletion of ClC-c in intestinal stem/progenitor cells is due to inhibition of the EGFR signalling pathway. CONCLUSION: Our findings reveal an ISC-specific function of ClC-c in regulating stem cell maintenance and proliferation, thereby providing new insights into the functional links among the chloride channel family, ISC proliferation and tissue homeostasis.

Ipomoea staphylina Attenuates Potassium Dichromate-Induced Nephrotoxicity in Wistar Rats via Antioxidant and Antiapoptotic Effects.

Occupational and environmental exposure to chromium compounds leads to nephrotoxicity to humans and animals due to the overproduction of ROS. Our study was aimed to demonstrate the shielding effect of hydroethanolic extract of Ipomoea staphylina (HEIS) bark on male Wistar rats challenged with potassium dichromate (K2Cr2O7). Division of animals was done in 4 groups' viz., normal control, K2Cr2O7 control, K2Cr2O7+HEIS (100 mg/kg), and K2Cr2O7+HEIS (200 mg/kg). Except for the normal control group, other groups were challenged with a single dose (subcutaneous) of K2Cr2O7 (15 mg/kg) and then treated with HEIS (100 and 200 mg/kg) for 1 week. It was observed that animals treated with K2Cr2O7 showed a notable increase in serum creatinine, blood urea, and BUN and dwindles in protein level. These changes were significantly reversed after a 1-week treatment with HEIS (100 and 200 mg/kg). Moreover, HEIS (100 and 200 mg/kg) showed a remarkable improvement in the activity of antioxidant enzymes (GPx, CAT, and SOD) and decreased the levels of TNF-α and IL-1ß in the kidney. Furthermore, treatment with HEIS (100 and 200 mg/kg) notably decreased the activity of caspase-3 and improved the level of HO-1 especially in the K2Cr2O7+ HEIS (200 mg/kg) group. Also, the histopathological study of the kidney supported the protective effects of HEIS. Hence, HEIS bark holds a notable protective effect against K2Cr2O7-induced nephrotoxicity in rats.

High expression of disabled homolog 2-interacting protein contributes to tumor development and proliferation in cutaneous squamous cell carcinoma.

BACKGROUND: Disabled homolog 2-interacting protein (DAB2IP), a Ras GTPase-activating protein, is downregulated in several cancers. Its depletion is involved in tumor cell proliferation, apoptosis, and metastasis, as well as epithelial-mesenchymal transition. The present study aimed to explore the potential role of DAB2IP in cutaneous squamous cell carcinoma (cSCC) and provide a theoretical basis for the diagnosis and targeted therapy of cSCC. METHODS: The clinicopathological features of DAB2IP expression in cSCC were analyzed by immunohistochemistry, and the effects of DAB2IP on SCL-1 cell behavior were determined via genetic interference in vitro. SCL-1 cell lines that exhibited reduced expression of DAB2IP and a scrambled shRNA control were constructed using a lentivirus vector-based shRNA technique. RNA extraction, reverse transcription-quantitative PCR (RT-qPCR), MTT assay, colony formation test, cell cycle analysis, apoptosis test, transwell assay, wound-healing assay, in vitro invasive assay were used in this study. RESULTS: The immunohistochemical results demonstrated that the expression of DAB2IP was higher in cSCC tissues than in soft fibroma. The level of DAB2IP expression was associated with the degree of malignancy and the depth of tumor infiltration; however, it had no association with patients' sex, tumor size, location, or phenotype. The results of the MTT, cell cycle, apoptosis, and invasion experiments demonstrated that knockdown of DAB2IP inhibited the viability and invasion of SCL-1 cells in vitro. CONCLUSIONS: High expression of DAB2IP may contribute to the development and proliferation of cSCC.

Genome mining as a biotechnological tool for the discovery of novel marine natural products.

Compared to terrestrial environments, the oceans harbor a variety of environments, creating higher biodiversity, which gives marine natural products a high occurrence of significant biology and novel chemistry. However, traditional bioassay-guided isolation and purification strategies are severely limiting the discovery of additional novel natural products from the ocean. With an increasing number of marine microorganisms being sequenced, genome mining is gradually becoming a powerful tool to retrieve novel marine natural products. In this review, we have summarized genome mining approaches used to analyze key enzymes of biosynthetic pathways and predict the chemical structure of new gene clusters by introducing successful stories that used genome mining strategy to identify new marine-derived compounds. Furthermore, we also put forward challenges for genome mining techniques and their proposed solutions. The detailed analysis of the genome mining strategy will help researchers to understand this novel technique and its application. With the development of a genome sequence, genome mining strategies will be applied more widely, which will drive rapid development in the field of marine natural product development.

Effects of cotrimoxazole prophylaxis on Talaromyces marneffei infection in HIV/AIDS patients receiving antiretroviral therapy: a retrospective cohort study.

The dimorphic fungus Talaromyces marneffei (TM) is a common cause of HIV-associated opportunistic infections in Southeast Asia. Cotrimoxazole (CTX) inhibits folic acid synthesis which is important for the survival of many bacteria, protozoa, and fungi and has been used to prevent several opportunistic infections among HIV/AIDS patients. We question whether CTX is effective in preventing TM infection. To investigate this question, we conducted an 11-year (2005-2016) retrospective observational cohort study of all patients on the Chinese national antiretroviral therapy (ART) programme in Guangxi, a province with high HIV and TM burden in China. Survival analysis was conducted to investigate TM cumulative incidence, and Cox regression and propensity score matching (PSM) were used to evaluate the effect of CTX on TM incidence. Of the 3359 eligible individuals contributing 10,504.66 person-years of follow-up, 81.81% received CTX within 6 months after ART initiation, and 4.73% developed TM infection, contributing 15.14/1,000 person-year TM incidence rate. CTX patients had a significantly lower incidence of TM infection than non-CTX patients (4.11% vs. 7.53%; adjusted hazard ratio (aHR) = 0.50, 95% CI 0.35-0.73). CTX reduced TM incidence in all CD4+ cell subgroups (<50 cells/µL, 50-99 cells/µL, 100-199 cells/µL), with the highest reduction observed in patients with a baseline CD4+ cell count <50 cells/µL in both Cox regression and the PSM analyses. In conclusion, in addition to preventing other HIV-associated opportunistic infections, CTX prophylaxis has the potential to prevent TM infection in HIV/AIDS patients receiving ART.

An optimal BMI range associated with a lower risk of mortality among HIV-infected adults initiating antiretroviral therapy in Guangxi, China.

Previous studies investigating HIV-infected patients suggested a direct link between underweight and the mortality rate of AIDS. However, there was a lack of evidence showing the optimal range of initial body mass index (BMI) patients maintain during antiretroviral therapy (ART). We aimed to evaluate associations of the BMI values pre-ART and during the entire ART duration with mortality among HIV-positive individuals. In total, 5101 HIV/AIDS patients, including 1439 (28.2%) underweight, 3047 (59.7%) normal-weight, 548 (10.7%) overweight and 67 (1.3%) obese patients, were included in this cohort. The cumulative mortality of underweight, normal-weight, and overweight were 2.4/100 person-years (95% CI 1.9-2.9), 1.1/100 person-years (95% CI 0.9-1.3), and 0.5/100 person-years (95% CI 0.1-0.9), respectively. Cumulative mortality was lower in both the normal-weight and overweight populations than in the underweight population, with an adjusted hazard ratio (AHR) of 0.5 (95% CI 0.4-0.7, p < 0.001) and 0.3 (95% CI 0.1-0.6, p = 0.002), respectively. Additionally, in the 1176 patients with available viral load data, there was significant difference between the underweight and normal-weight groups after adjustment for all factors, including viral load (p = 0.031). This result suggests that HIV-infected patients in Guangxi maintaining a BMI of 19-28 kg/m2, especially 24-28 kg/m2, have a reduced risk of death.

Incidence and types of HIV-1 drug resistance mutation among patients failing first-line antiretroviral therapy.

OBJECTIVE: This study aims to investigate the prevalence and types of drug resistance mutations among patients failing first-line antiretroviral therapy (ART). METHODS: Plasma samples from 112 patients with human immunodeficiency virus-1 (HIV-1) were collected for virus RNA extract and gene amplification. The mutations related to drug resistance were detected and the incidence was statistically analyzed, and the drug resistance rate against common drugs was also evaluated. RESULTS: 103 cases were successfully amplified, and the main drug resistance mutations in the reverse transcriptase (RT) region were M184V (50.49%), K103N (28.16%), Y181C (25.24%), and K65R (27.18%), while no drug main resistance mutation was found in the protease (PR) region. The incidence of drug resistance mutations was significantly different among patients with different ages, routes of infection, duration of treatment, initial ART regimens and viral load. The drug resistance rate to the common drugs was assessed, including Efavirenz (EFV, 71.84%), Nevirapine (NVP, 74.76%), Lamivudine (3TC, 66.02%), Zidovudine (AZT, 4.85%), Stavudine (D4T, 16.51%), and Tenofovir (TDF, 21.36%). CONCLUSION: The drug resistance mutations to NRTIs and NNRTIs are complex and highly prevalent, which was the leading cause of first-line ART failure. This study provides significant theoretical support for developing the second-line and third-line therapeutic schemes.

Dual Targeting of Bile Acid Receptor-1 (TGR5) and Farnesoid X Receptor (FXR) Prevents Estrogen-Dependent Bone Loss in Mice.

Osteoporosis is a global bone disease characterized by reduced bone mineral density (BMD) and increased risk of fractures. The risk of developing osteoporosis increases with aging, especially after menopause in women. Discovering the signaling pathways that play a significant role in aging- and menopause-induced osteoporosis should accelerate osteoporosis drug discovery. In this study, we found that bile acid membrane receptor Tgr5 knockout C57BL/6J mice had similar bone mass as wild-type mice during early and middle-age (before 4 months old) bone remodeling; however, Tgr5-/- markedly decreased bone mass in aged (more than 7 months old) and ovariectomized (OVX) mice compared with wild-type mice. Moreover, Tgr5 knockout strongly induced osteoclast differentiation but had no effect on osteoblast activity. Treatment with different TGR5 agonists consistently inhibited osteoclast differentiation. Importantly, our results showed that Tgr5 regulates osteoclastogenesis by the AMP-activated protein kinase (AMPK) signaling pathway, which is a central metabolic pathway involved in the pathophysiology of aging and age-related diseases. The bile acid nuclear receptor FXR is an established regulator of bone metabolism. We screened the derivatives of betulinic acid (BA), a known TGR5 agonist, to identify novel dual agonists of FXR and TGR5. The derivative SH-479, a pentacyclic triterpene acid, could activate both TGR5 and FXR, with a better inhibitory effect on osteoclastogenesis compared with agonists solely activating FXR or TGR5 and additionally enhanced osteoblastogenesis. Furthermore, SH-479 therapeutically abrogated bone loss in C57BL/6J mice through the bone remodeling pathways. Together, our results demonstrate that dual targeting the bile acid membrane receptor TGR5 and nuclear receptor FXR is a promising strategy for osteoporosis. © 2018 American Society for Bone and Mineral Research.