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Bone marrow-derived mesenchymal stem cells: A promising therapeutic option for the treatment of diabetic foot ulcers

Dama G, Du J, Zhu X, Liu Y, Lin J

Diabetes Res Clin Pract, 2023 Jan;195:110201.
PMID: 36493913 DOI: 10.1016/j.diabres.2022.110201

Chronic wounds fail to heal through the three normal stages of healing (inflammatory, proliferative, and remodelling), resulting in a chronic tissue injury that is not repaired within the average time limit. Patients suffering from type 1 and type 2 diabetes are prone to develop diabetic foot ulcers (DFUs), which commonly develop into chronic wounds that are non treatable with conventional therapies. DFU develops due to various risk factors, such as peripheral neuropathy, peripheral vascular disease, arterial insufficiency, foot deformities, trauma and impaired resistance to infection. DFUs have gradually become a major problem in the health care system worldwide. In this review, we not only focus on the pathogenesis of DFU but also comprehensively summarize the outcomes of preclinical and clinical studies thus far and the potential therapeutic mechanism of bone marrow-derived mesenchymal stem cells (BMSCs) for the treatment of DFU. Based on the published results, BMSC transplantation can contribute to wound healing through growth factor secretion, anti-inflammation, differentiation into tissue-specific cells, neovascularization, re-epithelialization and angiogenesis in DFUs. Moreover, clinical trials showed that BMSC treatment in patients with diabetic ulcers improved ulcer healing and the ankle-brachial index, ameliorated pain scores, and enhanced claudication walking distances with no reported complications. In conclusion, although BMSC transplantation exhibits promising therapeutic potential in DFU treatment, additional studies should be performed to confirm their efficacy and long-term safety in DFU patients.
Electrospun of functionalized mesoporous UiO-66 as the selective coating of solid phase microextraction Arrow for the determination of nine alkylphenols

Yang P, Zhu X, Lan H, Wu Y, Pan D

Mikrochim Acta, 2024 Mar 08;191(4):188.
PMID: 38457047 DOI: 10.1007/s00604-024-06248-w

A solid-phase microextraction (SPME) Arrow and high-performance liquid chromatography-UV detector (HPLC-UV, detection at 225 nm) based method was developed for the selective determination of nine alkylphenols (APs) in milk. The functionalized mesoporous UiO-66 (4-meso-UiO-66) was utilized as the new coating material, which was synthesized by post-modification of pore-expanded UiO-66-NH2 by an esterification reaction with 4-pentylbenzoic acid. It was fully characterized by X-ray photoelectron spectroscopy (XPS), fourier transformation infrared spectrometry, nitrogen sorption-desorption test, scanning electron microscopy, transmission electron microscopy, and X-ray diffractometer. The characterization results showed the ester groups and benzene rings were introduced into the 4-meso-UiO-66, and the mesoporous structure was predominant in the 4-meso-UiO-66. The extraction mechanism of 4-meso-UiO-66 to APs is the synergistic effect of Zr-O electrostatic interaction and the size exclusion effect resulting from XPS, selectivity test, and nitrogen sorption-desorption test. The electrospinning technique was utilized to fabricate the 4-meso-UiO-66 coated SPME Arrow and polyacrylonitrile (PAN) was used as the adhesive. The mass rate of 4-meso-UiO-66 to PAN and the electrospinning time were evaluated. The extraction and desorption parameters were also studied. The linear range of this method was 0.2-1000 μg L-1 with a coefficient of determination greater than 0.9989 under the optimal conditions. The detection limits were 0.05-1 μg L-1, the inter-day and intra-day precision (RSD) were 2.8-11.5%, and the recovery was 83.6%-112%. The reusability study showed that the extraction performance of this new SPME Arrow could be maintained after 80 adsorption-desorption cycles. This method showed excellent applicability for the selective determination of APs in milk.
PCR tools for the verification of the specific identity of ascaridoid nematodes from dogs and cats

Li MW, Lin RQ, Chen HH, Sani RA, Song HQ, Zhu XQ

Mol Cell Probes, 2007 Oct-Dec;21(5-6):349-54.
PMID: 17532185

Based on the sequences of the internal transcribed spacers (ITS-1 and ITS-2) of nuclear ribosomal DNA (rDNA) of Toxocara canis, Toxocara cati, Toxocara malaysiensis and Toxascaris leonina, specific forward primers were designed in the ITS-1 or ITS-2 for each of the four ascaridoid species of dogs and cats. These primers were used individually together with a conserved primer in the large subunit of rDNA to amplify partial ITS-1 and/or ITS-2 of rDNA from 107 DNA samples from ascaridoids from dogs and cats in China, Australia, Malaysia, England and the Netherlands. This approach allowed their specific identification, with no amplicons being amplified from heterogeneous DNA samples, and sequencing confirmed the identity of the sequences amplified. The minimum amounts of DNA detectable using the PCR assays were 0.13-0.54ng. These PCR assays should provide useful tools for the diagnosis and molecular epidemiological investigations of toxocariasis in humans and animals.
Differentiating the extent of cartilage repair in rabbit ears using nonlinear optical microscopy

Zhu XQ, Xu YH, Liao CX, Liu WG, Cheng KK, Chen JX

J Microsc, 2015 Nov;260(2):219-26.
PMID: 26366638 DOI: 10.1111/jmi.12288

Nonlinear optical microscopy (NLOM) was used as a noninvasive and label-free tool to detect and quantify the extent of the cartilage recovery. Two cartilage injury models were established in the outer ears of rabbits that created a different extent of cartilage recovery based on the presence or absence of the perichondrium. High-resolution NLOM images were used to measure cartilage repair, specifically through spectral analysis and image texture. In contrast to a wound lacking a perichondrium, wounds with intact perichondria demonstrated significantly larger TPEF signals from cells and matrix, coarser texture indicating the more deposition of type I collagen. Spectral analysis of cells and matrix can reveal the matrix properties and cell growth. In addition, texture analysis of NLOM images showed significant differences in the distribution of cells and matrix of repaired tissues with or without perichondrium. Specifically, the decay length of autocorrelation coefficient based on TPEF images is 11.2 ± 1.1 in Wound 2 (with perichondrium) and 7.5 ± 2.0 in Wound 1 (without perichondrium), indicating coarser image texture and faster growth of cells in repaired tissues with perichondrium (p < 0.05). Moreover, the decay length of autocorrelation coefficient based on collagen SHG images also showed significant difference between Wound 2 and 1 (16.2 ± 1.2 vs. 12.2 ± 2.1, p < 0.05), indicating coarser image texture and faster deposition of collagen in repaired tissues with perichondrium (Wound 2). These findings suggest that NLOM is an ideal tool for studying cartilage repair, with potential applications in clinical medicine. NLOM can capture macromolecular details and distinguish between different extents of cartilage repair without the need for labelling agents.
Molecular characterization of a Toxocara variant from cats in Kuala Lumpur, Malaysia

Zhu XQ, Jacobs DE, Chilton NB, Sani RA, Cheng NA, Gasser RB

Parasitology, 1998 Aug;117 ( Pt 2):155-64.
PMID: 9778638

The ascaridoid nematode of cats from Kuala Lumpur, Malaysia, previously identified morphologically as Toxocara canis, was characterized using a molecular approach. The nuclear ribosomal DNA (rDNA) region spanning the first internal transcribed spacer (ITS-1), the 5.8S gene and the second internal transcribed spacer (ITS-2) was amplified and sequenced. The sequences for the parasite from Malaysian cats were compared with those for T. canis and T. cati. The sequence data showed that this taxon was genetically more similar to T. cati than to T. canis in the ITS-1, 5.8S and ITS-2. Differences in the ITS-1 and ITS-2 sequences between the taxa (9.4-26.1%) were markedly higher than variation between samples within T. canis and T. cati (0-2.9%). The sequence data demonstrate that the parasite from Malaysian cats is neither T. canis nor T. cati and indicate that it is a distinct species. Based on these data, PCR-linked restriction fragment length polymorphism (RFLP) and single-strand conformation polymorphism (SSCP) methods were employed for the unequivocal differentiation of the Toxocara variant from T. canis and T. cati. These methods should provide valuable tools for studying the life-cycle, transmission pattern(s) and zoonotic potential of this parasite.
Effects of descending or ascending stair exercise on body composition, insulin sensitivity, and inflammatory markers in young Chinese women with obesity: A randomized controlled trial

Chow BC, Li S, Zhu X, Jiao J, Quach B, Baker JS, et al.

J Sports Sci, 2021 Mar;39(5):496-502.
PMID: 33012244 DOI: 10.1080/02640414.2020.1829362

We examined the effects of descending (DSE) or ascending (ASE) stair exercise on body composition, insulin sensitivity, and inflammatory markers in young Chinese women with obesity. Thirty-six participants were randomly assigned into three groups DSE, ASE and a control group. The DSE and ASE groups performed three sessions of stair walking per week for 12 weeks with a gradual increase in repetitions. Following the exercise interventions, body composition related variables obtained by Dual-energy X-ray absorptiometry scans significantly decreased. Abdominal fat decreased in the DSE group only. Moreover, Insulin sensitivity improved significantly 3.5-fold in the DSE group compared with ASE group (insulin: -33.2% vs. -9.8%, homoeostasis model assessment for insulin resistance: -35.6% vs. -10.8%). Pro-inflammatory factors showed significant decreases in tumour necrosis factor-α (TNF-α) (-39.9% vs. -23.2%) for both intervention groups. The reduction in TNF-α concentrations in the DSE group was significantly different compared to the other two groups. Interleukin-6 significantly decreased in both exercise protocols. Our results show that 12-weeks induced stair walking improved body composition parameters in Chinese females with obesity. The results also demonstrate the superiority of the DSE protocol for improving insulin sensitivity. These findings may be attributable to the decreases observed in TNF- α levels.
Effects of foam nickel supplementation on anaerobic digestion: Direct interspecies electron transfer

Guo X, Sun C, Lin R, Xia A, Huang Y, Zhu X, et al.

J Hazard Mater, 2020 11 15;399:122830.
PMID: 32937692 DOI: 10.1016/j.jhazmat.2020.122830

Stimulating direct interspecies electron transfer with conductive materials is a promising strategy to overcome the limitation of electron transfer efficiency in syntrophic methanogenesis of industrial wastewater. This paper assessed the impact of conductive foam nickel (FN) supplementation on syntrophic methanogenesis and found that addition of 2.45 g/L FN in anaerobic digestion increased the maximum methane production rate by 27.4 % (on day 3) while decreasing the peak production time by 33 % as compared to the control with no FN. Cumulative methane production from day 2 to 6 was 14.5 % higher with addition of 2.45 g/L FN than in the control. Levels of FN in excess of 2.45 g/L did not show benefits. Cyclic voltammetry results indicated that the biofilm formed on the FN could generate electrons. The dominant bacterial genera in suspended sludge were Dechlorobacter and Rikenellaceae DMER64, whereas that in the FN biofilm was Clostridium sensu stricto 11. The dominant archaea Methanosaeta in the FN biofilm was enriched by 14.1 % as compared to the control.
Fulltext Efficacy and safety of Jianpishengsui for chemotherapy-related fatigue in patients with non-small cell lung cancer: study protocol for a randomized placebo-controlled clinical trial

Xiao Z, Hu L, Lin J, Lu L, Huang X, Zhu X, et al.

Trials, 2020 Jan 16;21(1):94.
PMID: 31948475 DOI: 10.1186/s13063-019-3982-3

BACKGROUND: Chemotherapy-related fatigue (CRF) is a common symptom in non-small cell lung cancer (NSCLC) patients. A Chinese herbal formula cream for oral application, called Jianpishengsui (JPSS), is extensively used in the First Affiliated Hospital of Guangzhou University of Chinese Medicine as an internal preparation for CRF and is associated with a promising response. Due to the lack of high-quality clinical evidence, a randomized placebo-controlled trial is required to assess the efficacy and safety of JPSS.
METHODS/DESIGN: The efficacy and safety of JPSS herbal formula cream will be evaluated through a prospective, randomized, placebo-controlled trial conducted in the First Affiliated Hospital of Guangzhou University of Chinese Medicine. NSCLC patients with CRF will be randomized into two groups at a ratio of 1:1. Each group will receive either 15 g of the oral JPSS herbal formula cream or placebo twice a day from day 6 to day 20 during two courses of paclitaxel + platinum/docetaxel + platinum/pemetrexed + platinum (TP/DP/AP) chemotherapy. The primary endpoint is the difference in the degree of fatigue between baseline (the day before the start of the intervention) and day 42, which will be assessed by the Revised Piper Fatigue Scale score. The secondary endpoints are quality of life (measured by the 43-item European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Lung Cancer C43), Eastern Cooperative Oncology Group Performance Status, and Traditional Chinese Medicine syndrome score. The toxicity of the treatments will also be evaluated at the same time. All outcomes will be measured at baseline, day 6, day 21, and day 42 of the treatment.
DISCUSSION: This randomized trial will investigate the efficacy and safety of JPSS applied for CRF in patients with NSCLC.
TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900023451. Registered on 28 May 2019.
Catalytic co-hydrothermal carbonization of food waste digestate and yard waste for energy application and nutrient recovery

He M, Zhu X, Dutta S, Khanal SK, Lee KT, Masek O, et al.

Bioresour Technol, 2022 Jan;344(Pt B):126395.
PMID: 34822987 DOI: 10.1016/j.biortech.2021.126395

Hydrothermal carbonization (HTC) provides a promising alternative to valorize food waste digestate (FWD) and avoid disposal issues. Although hydrochar derived from FWD alone had a low calorific content (HHV of 13.9 MJ kg-1), catalytic co-HTC of FWD with wet lignocellulosic biomass (e.g., wet yard waste; YW) and 0.5 M HCl exhibited overall superior attributes in terms of energy recovery (22.7 MJ kg-1), stable and comprehensive combustion behaviour, potential nutrient recovery from process water (2-fold higher N retention and 129-fold higher P extraction), and a high C utilization efficiency (only 2.4% C loss). In contrast, co-HTC with citric acid provided ∼3-fold higher autogenous pressure, resulting in a superior energy content of 25.0 MJ kg-1, but the high C loss (∼74%) compromised the overall environmental benefits. The results of this study established a foundation to fully utilize FWD and YW hydrochar for bioenergy application and resource recovery from the process water.
Fulltext Editorial: Model-informed drug development and evidence-based translational pharmacology

Zhao J, Zhu X, Tan S, Chen C, Kaddoumi A, Guo XL, et al.

Front Pharmacol, 2022;13:1086551.
PMID: 36578539 DOI: 10.3389/fphar.2022.1086551
Accelerating charge transfer via nonconjugated polyelectrolyte interlayers toward efficient versatile photoredox catalysis

Li T, Feng C, Yap BK, Zhu X, Xiong B, He Z, et al.

Commun Chem, 2021 Oct 22;4(1):150.
PMID: 36697810 DOI: 10.1038/s42004-021-00589-w

One of the challenges for high-efficiency single-component-based photoredox catalysts is the low charge transfer and extraction due to the high recombination rate. Here, we demonstrate a strategy to precisely control the charge separation and transport efficiency of the catalytic host by introducing electron or hole extraction interlayers to improve the catalytic efficiency. We use simple and easily available non-conjugated polyelectrolytes (NCPs) (i.e., polyethyleneimine, PEI; poly(allylamine hydrochloride), PAH) to form interlayers, wherein such NCPs consist of the nonconjugated backbone with charge transporting functional groups. Taking CdS as examples, it is shown that although PEI and PAH are insulators and therefore do not have the ability to conduct electricity, they can form good electron or hole transport extraction layers due to the higher charge-transfer kinetics of pendant groups along the backbones, thereby greatly improving the charge transfer capability of CdS. Consequently, the resultant PEI-/PAH-functionalized nanocomposites exhibit significantly enhanced and versatile photoredox catalysis.
Fulltext Exploring Guolin Qigong (Mind-Body Exercise) for Improving Cancer Related Fatigue in Cancer Survivors: A Mixed Method Randomized Controlled Trial Protocol

Low SLK, Ho GF, Liu B, Koh ES, Fei Y, Teo CS, et al.

Integr Cancer Ther, 2024;23:15347354241252698.
PMID: 38757745 DOI: 10.1177/15347354241252698

BACKGROUND: Cancer-related fatigue and its associated symptoms of sleep disorder and depression are prevalent in cancer survivors especially among breast, lung, and colorectal cancer survivors. While there is no gold standard for treating cancer-related fatigue currently, studies of mind-body exercises such as Qigong have reported promise in reducing symptoms. This study was designed to evaluate the feasibility and effect of Guolin Qigong on cancer-related fatigue and other symptoms in breast, lung and colorectal cancer survivors while exploring their perceptions and experiences of Guolin Qigong intervention.
METHODS: This is an open-label randomized controlled trial with 60 participants divided into 2 study groups in a 1:1 ratio. The intervention group will receive 12 weeks of Guolin Qigong intervention with a 4-week follow-up while control will receive usual care under waitlist. The primary outcome will be feasibility measured based on recruitment and retention rates, class attendance, home practice adherence, nature, and quantum of missing data as well as safety. The secondary subjective outcomes of fatigue, sleep quality and depression will be measured at Week-1 (baseline), Week-6 (mid-intervention), Week-12 (post-intervention), and Week-16 (4 weeks post-intervention) while an objective 24-hour urine cortisol will be measured at Week-1 (baseline) and Week-12 (post-intervention). We will conduct a semi-structured interview individually with participants within 3 months after Week-16 (4 weeks post-intervention) to obtain a more comprehensive view of practice adherence.
DISCUSSION: This is the first mixed-method study to investigate the feasibility and effect of Guolin Qigong on breast, lung, and colorectal cancer survivors to provide a comprehensive understanding of Guolin Qigong's intervention impact and participants' perspectives. The interdisciplinary collaboration between Western Medicine and Chinese Medicine expertise of this study ensures robust study design, enhanced participant care, rigorous data analysis, and meaningful interpretation of results. This innovative research contributes to the field of oncology and may guide future evidence-based mind-body interventions to improve cancer survivorship.
TRIAL REGISTRATION: This study has been registered with ANZCTR (ACTRN12622000688785p), was approved by Medical Research Ethic Committee of University Malaya Medical Centre (MREC ID NO: 2022323-11092) and recognized by Western Sydney University Human Research Ethics Committee (RH15124).
Fulltext Evaluating the roles of microRNAs associated with nonalcoholic fatty liver disease in hepatocellular carcinoma tumorigenesis: a systematic review and network analysis

Peng Q, Zhu X, Jiang Y, Peng M, Zheng D, Wang X, et al.

Front Med (Lausanne), 2024;11:1462513.
PMID: 39618816 DOI: 10.3389/fmed.2024.1462513

INTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease worldwide. Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide, with high morbidity and mortality. The rapidly increasing incidence of NAFLD is becoming an essential precursor of HCC globally. MicroRNAs (miRNAs) are involved in the progression of NAFLD and HCC.
METHOD: Potential miRNAs associated with NAFLD in HCC tumorigenesis were identified through a systematic review, and their roles were evaluated by data mining analysis. The biological function of the potential miRNA and its target genes in NAFLD and HCC were evaluated by bioinformatic analysis.
RESULT: MIR122 was identified as the potential miRNA associated with NAFLD and HCC. Then, MIR122 expression was significantly lower in HCC patients, and higher MIR122 levels were associated with significantly better overall survival. Next, the biological functions of MIR122 and target genes were predicted to be involved in inflammation, fibrosis, cell proliferation, invasion, metastasis, and apoptosis. In particular, the FOXO signaling pathway may regulate the above biological functions.
CONCLUSION: MIR122 was suggested to be involved in progressing from NAFLD to HCC through the PI3K/AKT/FOXO pathway.
SYSTEMATIC REVIEW REGISTRATION: PROSPERO, identifier: CRD 42024517940.
Fulltext Effects of different dietary supplements on athletic performance in soccer players: a systematic review and network meta-analysis

Luo H, Tengku Kamalden TF, Zhu X, Xiang C, Nasharuddin NA

J Int Soc Sports Nutr, 2025 Dec;22(1):2467890.
PMID: 39972597 DOI: 10.1080/15502783.2025.2467890

BACKGROUND: As dietary supplements play a crucial role in meeting the unique nutritional needs of soccer players, a growing body of studies are exploring the effects of dietary supplements on athletic performance in soccer players. The effectiveness of certain supplements, such as caffeine and creatine, remains debated due to inconsistent results across studies. Therefore, this systematic review and Bayesian network meta-analysis was conducted to tentatively identify the most effective dietary supplements for soccer players.
METHODS: We searched PubMed, Web of Science, Cochrane, Embase, and SPORTDiscus from database establishment to 5 February 2024 to identify randomized controlled trials (RCTs) evaluating the effects of different dietary supplements on athletic performance in soccer players. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials. A Bayesian network meta-analysis was performed using the R software and Stata 18.0. A subgroup analysis was conducted based on the competitive level of the athletes.
RESULTS: Eighty RCTs were included, with 1,425 soccer players randomly receiving 31 different dietary supplements or placebo. The network meta-analysis showed that compared with placebo, carbohydrate + protein (SMD: 2.2, very large), carbohydrate + electrolyte (SMD: 1.3, large), bovine colostrum (SMD: moderate) and caffeine (SMD: 0.29, small) were associated with a significant effect on increasing the distance covered. Kaempferia parviflora (SMD: 0.46, small) was associated with a significant effect on enhancing muscular strength. Beta-alanine (SMD: 0.83, moderate), melatonin (SMD: 0.75, moderate), caffeine (SMD: 0.37, small), and creatine (SMD: 0.33, small) were associated with a significant effect on enhancing jump height. Magnesium creatine chelate (SMD: -3.0, very large), melatonin (SMD: -1.9, large), creatine + sodium bicarbonate (SMD: -1.4, large), and arginine (SMD: -1.2, moderate) were associated with a significant effect on decreasing sprint time. Creatine + sodium bicarbonate (SMD: -2.3, very large) and caffeine (SMD: -0.38, small) were associated with a significant effect on improving agility. Sodium pyruvate (SMD: 0.50, small) was associated with a significant effect on increasing peak power. Magnesium creatine chelate (SMD: 1.3, large) and sodium pyruvate (SMD: 0.56, small) were associated with a significant effect on increasing mean power. Carbohydrate + electrolyte (SMD: -0.56, small) was associated with a significant effect on improving the rating of perceived exertion.
CONCLUSIONS: This study suggests that a range of dietary supplements, including caffeine, creatine, creatine + sodium bicarbonate, magnesium creatine chelate, carbohydrate + electrolyte, carbohydrate + protein, arginine, beta-alanine, bovine colostrum, Kaempferia parviflora, melatonin, and sodium pyruvate, can improve athletic performance in soccer players. This review provides evidence-based guidance for soccer coaches and nutritionists on using dietary supplements to enhance specific performance measures.
Fulltext Helminth-derived molecules: pathogenic and pharmacopeial roles

Zhang Y, Shen C, Zhu X, Leow CY, Ji M, Xu Z

J Biomed Res, 2024 Sep 25;38(6):1-22.
PMID: 39314046 DOI: 10.7555/JBR.38.20240177

Parasitic helminths, taxonomically comprising trematodes, cestodes, and nematodes, are multicellular invertebrates widely disseminated in nature and have afflicted people continuously for a long time. Helminths play potent roles in the host through generating a variety of novel molecules, including some excretory/secretory products and others that are involved in intracellular material exchange and information transfer as well as the initiation or stimulation of immune and metabolic activation. The helminth-derived molecules have developed powerful and diverse immunosuppressive effects to achieve immune evasion for parasite survival and establish chronic infections. However, they also improve autoimmune and allergic inflammatory responses and promote metabolic homeostasis by promoting metabolic reprogramming of various immune functions, and then inducing alternatively activated macrophages, T helper 2 cells, and regulatory T cells-mediated immune responses. Therefore, a deeper exploration of the immunopathogenic mechanism and immune regulatory mechanisms of helminth-derived molecules exerted in the host is crucial for understanding host-helminth interactions as well as the development of therapeutic drugs for infectious or non-infectious diseases. In this review, we focus on the properties of helminth-derived molecules to give an overview of the most recent scientific knowledge about their pathogenic and pharmacopeial roles in immune-metabolic homeostasis.
Association between indoor microbiome exposure and sick building syndrome (SBS) in junior high schools of Johor Bahru, Malaysia

Fu X, Norbäck D, Yuan Q, Li Y, Zhu X, Hashim JH, et al.

Sci Total Environ, 2021 Jan 20;753:141904.
PMID: 32890872 DOI: 10.1016/j.scitotenv.2020.141904

Sick building syndrome (SBS) is a collection of nonspecific syndromes linked with the built environment. The occurrence of SBS is associated with humidity, ventilation, moulds and microbial compounds exposure. However, no study has reported the association between indoor microbiome and SBS. In this study, 308 students were surveyed for SBS symptoms from 21 classrooms of 7 junior high schools from Johor Bahru, Malaysia, and vacuum dust from floor, desks and chairs was collected. High throughput amplicon sequencing (16S rRNA gene and ITS region) and quantitative PCR were conducted to characterize the absolute concentration of bacteria and fungi taxa. In total, 326 bacterial and 255 fungal genera were detected in dust with large compositional variation among classrooms. Also, half of these samples showed low compositional similarity to microbiome data deposited in the public database. The number of observed OTUs in Gammaproteobacteria was positively associated with SBS (p = 0.004). Eight microbial genera were associated with SBS (p
Volatile-char interactions during biomass pyrolysis: Cleavage of C-C bond in a β-5 lignin model dimer by amino-modified graphitized carbon nanotube

Huang Y, Liu S, Zhang J, Syed-Hassan SSA, Hu X, Sun H, et al.

Bioresour Technol, 2020 Jul;307:123192.
PMID: 32220819 DOI: 10.1016/j.biortech.2020.123192

This study investigated the interactions between volatile and char during biomass pyrolysis at 400 °C, employing a β-5 lignin dimer and amino-modified graphitized carbon nanotube (CNT-NH2) as their models, respectively. The results demonstrated that both -NH2 and its carrier (CNT) facilitated the conversion of the β-5 dimer, which significantly increased from 9.7% (blank run), to 61.6% (with CNT), and to 96.6% (with CNT-NH2). CNT mainly favored the breakage of C-O bond in the feedstock to produce dimers with a yield of 55.5%, while CNT-NH2 promoted the cleavage of both C-O and C-C bonds to yield monomers with a yield up to 63.4%. Such significant changes in the pyrolysis behaviors of the β-5 lignin dimer after the introduction of CNT-NH2 were considered to be mainly caused by hydrogen-bond formations between -NH2 and the dimeric feedstock/products, in addition to the π-π stacking between CNT and aromatic rings.
Fulltext Molecular Characteristics of Burkholderia pseudomallei Collected From Humans in Hainan, China

Zhu X, Chen H, Li S, Wang LC, Wu DR, Wang XM, et al.

Front Microbiol, 2020;11:778.
PMID: 32457710 DOI: 10.3389/fmicb.2020.00778

Melioidosis is a common infectious disease in Southeast Asia and Northern Australia. In Hainan, several cases have been reported, but no systematic study has yet been done on the molecular epidemiology profiles of the organism. An investigation of the molecular epidemiology links and population structure of Burkholderia pseudomallei would help to better understand the clonally of the isolates and differences among them. In this study, multilocus variable-number tandem repeat analysis (MLVA), and multilocus sequence typing (MLST) were applied to examine the epidemiological relatedness and population structure of 166 B. pseudomallei isolates obtained during 2002-2014 in Hainan, China. Both the MLVA_4 and MLST approaches had high discriminatory power for this population, with diversity indices of 0.9899 and 0.9457, respectively. However, the MLVA_4 assay showed a higher discriminatory power than the MLST approach, and a variable-number tandem repeat (VNTR3 933) found by the MLVA approach was the most useful in discriminating strains from this province. A total of 166 strains yielded 99 MLVA_4 genotypes, of which 34 genotypes were shared by 101 isolates, for a clustering rate of 60.8% (101/166), which suggested that some cases may have a common source. Additionally, 65 isolates showed distinct genotypes, indicating that more than 39.2% (65/166) of melioidosis cases in Hainan had epidemiologically unrelated or sporadic characteristics. The 166 isolates were resolved into 48 STs, of which five STs (ST55, -70, -46, -50, and -58) were here found to be predominant. Phylogenetic analysis of 116 isolates conducted using the eBURST v3 segregated the 48 STs into eight groups with ST50 as predicted founder, and 21 STs were found to be singletons, which suggest that the strains in the Hainan region represent a high diversity of ST clones, indicating that many B. pseudomallei clone groups are endemic to this region. Moreover, ST50 had 5 SLV, 7 DLV, 6 TLV, and 29 satellite STs and formed a radial expansion pattern, suggesting that the melioidosis epidemic in this study was mainly caused by the clonal expansion of ST 50. Phylogenetic analysis on global scale suggests that China's isolates are closely related to isolates from Southeast Asia, particularly from Thailand and Malaysia.
Fulltext Synthesis of 2,4-Diaminopyrimidine Core-Based Derivatives and Biological Evaluation of Their Anti-Tubercular Activities

Ouyang Y, Yang H, Zhang P, Wang Y, Kaur S, Zhu X, et al.

Molecules, 2017 Sep 22;22(10).
PMID: 28937657 DOI: 10.3390/molecules22101592

Tuberculosis (TB) is a chronic, potentially fatal disease caused by Mycobacterium tuberculosis (Mtb). The dihyrofolate reductase in Mtb (mt-DHFR) is believed to be an important drug target in anti-TB drug development. This enzyme contains a glycerol (GOL) binding site, which is assumed to be a useful site to improve the selectivity towards human dihyrofolate reductase (h-DHFR). There have been previous attempts to design drugs targeting the GOL binding site, but the designed compounds contain a hydrophilic group, which may prevent the compounds from crossing the cell wall of Mtb to function at the whole cell level. In the current study, we designed and synthesized a series of mt-DHFR inhibitors that contain a 2,4-diaminopyrimidine core with side chains to occupy the glycerol binding site with proper hydrophilicity for cell entry, and tested their anti-tubercular activity against Mtb H37Ra. Among them, compound 16l showed a good anti-TB activity (MIC = 6.25 μg/mL) with a significant selectivity against vero cells. In the molecular simulations performed to understand the binding poses of the compounds, it was noticed that only side chains of a certain size can occupy the glycerol binding site. In summary, the novel synthesized compounds with appropriate side chains, hydrophobicity and selectivity could be important lead compounds for future optimization towards the development of future anti-TB drugs that can be used as monotherapy or in combination with other anti-TB drugs or antibiotics. These compounds can also provide much information for further studies on mt-DHFR. However, the enzyme target of the compounds still needs to be confirmed by pure mt-DHFR binding assays.
Extracellular vesicle-transmitted miR-671-5p alleviates lung inflammation and injury by regulating the AAK1/NF-κB axis

Lian J, Zhu X, Du J, Huang B, Zhao F, Ma C, et al.

Mol Ther, 2023 May 03;31(5):1365-1382.
PMID: 36733250 DOI: 10.1016/j.ymthe.2023.01.025

Mesenchymal stem cells regulate remote intercellular signaling communication via their secreted extracellular vesicles. Here, we report that menstrual blood-derived stem cells alleviate acute lung inflammation and injury via their extracellular vesicle-transmitted miR-671-5p. Disruption of this abundantly expressed miR-671-5p dramatically reduced the ameliorative effect of extracellular vesicles released by menstrual blood-derived stem cells on lipopolysaccharide (LPS)-induced pulmonary inflammatory injury. Mechanistically, miR-671-5p directly targets the kinase AAK1 for post-transcriptional degradation. AAK1 is found to positively regulate the activation of nuclear factor κB (NF-κB) signaling by controlling the stability of the inhibitory protein IκBα. This study identifies a potential molecular basis of how extracellular vesicles derived from mesenchymal stem cells improve pulmonary inflammatory injury and highlights the functional importance of the miR-671-5p/AAK1 axis in the progression of pulmonary inflammatory diseases. More importantly, this study provides a promising cell-based approach for the treatment of pulmonary inflammatory disorders through an extracellular vesicle-dependent pathway.

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