Development of a Time-Resolved Fluorescent Microsphere Test Strip for Rapid, On-Site, and Sensitive Detection of Picoxystrobin in Vegetables.

Picoxystrobin (PIC) is a fungicide extensively used for disease control in both crops and vegetables. Residues of PIC in vegetables pose a potential threat to human health due to their accumulation in the food chain. In this study, a specific PIC monoclonal antibody (mAb) was developed by introducing a carboxylic acid arm into PIC and subsequently preparing a hapten and an artificial antigen. A sensitive and rapid time-resolved fluorescence immunochromatographic assay (TRFICA) was established based on the mAb. Subsequently, using a time-resolved fluorescent microsphere (TRFM) as signal probe, mAbs and microspheres were covalently coupled. The activated pH, the mAb diluents, the mAb amount, and the probe amount were optimized. Under optimized conditions, the quantitative limits of detection (qLOD) of PIC in cucumber, green pepper, and tomato using TRFICA were established at 0.61, 0.26, and 3.44 ng/mL, respectively; the 50% inhibiting concentrations (IC50) were 11.76, 5.29, and 37.68 ng/mL, respectively. The linear ranges were 1.81-76.71, 0.80-35.04, and 8.32-170.55 ng/mL, respectively. The average recovery in cucumber, green pepper, and tomato samples ranged from 79.8% to 105.0%, and the corresponding coefficients of variation (CV) were below 14.2%. In addition, 15 vegetable samples were selected and compared with the results obtained using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The results revealed a high degree of concordance between the proposed method and UPLC-MS/MS. In conclusion, the devised TRFICA method is a valuable tool for rapid, on-site, and highly sensitive detection of PIC residues in vegetables.

Nosocomial outbreak of colistin-resistant, carbapenemase-producing Klebsiella pneumoniae ST11 in a medical intensive care unit.

OBJECTIVES: Klebsiella pneumoniae is an important opportunistic Gram-negative pathogen. This study describes an outbreak due to colistin-resistant and carbapenem-resistant Klebsiella pneumoniae (ColR-CRKP) in a tertiary hospital related to six patients successively admitted to the department of medical intensive care unit (MICU) between March 11 and April 29, 2021. METHODS: Phenotypic characterization was conducted on 16 ColR-CRKP strains obtained from six infected patients and five ColR-CRKP strains isolated from 48 environmental samples, followed by whole-genome sequencing (WGS) and polymerase chain reaction (PCR) analysis. RESULTS: All ColR-CRKP strains showed resistance to commonly used antibiotics. Whole-genome sequencing revealed a variety of resistance genes such as blaKPC-2, blaCTX-M-65, and blaTEM-4 present in all strains, which is consistent with their antimicrobial resistance profile. All isolates were identified as the high-risk sequence type 11 (ST11) clonal lineage by multilocus sequencing typing (MLST) and subsequently clustered into a single clonal type by core genome MLST (cgMLST). IS5-like element ISKpn26 family transposase insertion mutations at positions 74 nucleotides in the mgrB gene were the main cause of colistin resistance in these ColR-CRKP. The variations of genes were verified by PCR. SCOTTI analysis demonstrated the transmission pathway of the ColR-CRKP between the patients. CONCLUSION: Our study highlights the importance of coordinated efforts between clinical microbiologists and infection control teams to implement aggressive surveillance cultures and proper bacterial genotyping to diagnose nosocomial infections and take control measures. Routine surveillance and the use of advanced sequencing technologies should be implemented to enhance nosocomial infection control and prevention measures.

Downregulated BMP-Smad1/5/8 signaling causes emphysema via dysfunction of alveolar type II epithelial cells.

Bone morphogenetic protein (BMP)-Smad1/5/8 signaling plays a crucial regulatory role in lung development and adult lung homeostasis. However, it remains elusive whether BMP-Smad1/5/8 signaling is involved in the pathogenesis of emphysema. In this study, we downregulated BMP-Smad1/5/8 signaling by overexpressing its antagonist Noggin in adult mouse alveolar type II epithelial cells (AT2s), resulting in an emphysematous phenotype mimicking the typical pathological features of human emphysema, including distal airspace enlargement, pulmonary inflammation, extracellular matrix remodeling, and impaired lung function. Dysregulation of BMP-Smad1/5/8 signaling in AT2s leads to inflammatory destruction dominated by macrophage infiltration, associated with reduced secretion of surfactant proteins and inhibition of AT2 proliferation and differentiation. Reactivation of BMP-Smad1/5/8 signaling by genetics or chemotherapy significantly attenuated the morphology and pathophysiology of emphysema and improved the lung function in Noggin-overexpressing lungs. We also found that BMP-Smad1/5/8 signaling was downregulated in cigarette smoke-induced emphysema, and that enhancing its activity in AT2s prevented or even reversed emphysema in the mouse model. Our data suggest that BMP-Smad1/5/8 signaling, located at the top of the signaling cascade that regulates lung homeostasis, represents a key molecular regulator of alveolar stem cell secretory and regenerative function, and could serve as a potential target for future prevention and treatment of pulmonary emphysema. © 2023 The Pathological Society of Great Britain and Ireland.

Different Physiological Responses to Continuous Drought between Seedlings and Younger Individuals of Haloxylon ammodendron.

Drought is an important environmental factor that influences physiological processes in plants; however, few studies have examined the physiological mechanisms underlying plants' responses to continuous drought. In this study, the seedlings and younger individuals of Haloxylon ammodendron were experimentally planted in the southern part of the Gurbantunggut Desert. We measured their photosynthetic traits, functional traits and non-structural carbohydrate contents (NSCs) in order to assess the effects of continuous drought (at 15-day and 30-day drought points) on the plants' physiological responses. The results showed that at the 15-day (15 d) drought point, the leaf light-saturated net photosynthetic rate (An) values of both the seedlings and the younger individuals were decreased (by -68.9% and -45.2%, respectively). The intrinsic water use efficiency (iWUE) of the seedlings was significantly lower than that of the control group (-52.2%), but there was no diffenrence of iWUE observed in younger individuals. At the 30-day (30 d) drought point, a decrease in the An (-129.8%) of the seedlings was induced via biochemical inhibition, with a lower potential maximum photochemical rate (Fv/Fm, 0.42) compared with the control group, while a decrease in the An (-52.3%) of the younger individuals was induced due to lower stomatal conductance (gs, -50.5%). Our results indicated that prolonged drought induced a greater risk of seedling mortality as the relatively limited ability of stomatal regulation may increase the possibility of massive embolism, resulting in hydraulic failure.

Rapid Detection of blaKPC in Carbapenem-Resistant Enterobacterales Based on CRISPR/Cas13a.

Klebsiella pneumoniae carbapenemase (KPC) is a crucial enzyme that causes carbapenem resistance in Enterobacterales, and infections by these "superbugs" are extremely challenging to treat. Therefore, there is a pressing need for a rapid and accurate KPC detection test to control the prevalence of carbapenem-resistant Enterobacterales (CREs). In this study, we established a novel method for detection of blaKPC, the gene responsible for encoding KPC, based on a recombinase polymerase amplification (RPA) and a CRISPR/Cas13a reaction coupled to fluorophore activation (termed RPA-Cas13a assay). We carefully selected a pair of optimal amplification primers for blaKPC and achieved a lower limit of detection of approximately 2.5 copies/µL by repeatedly amplifying a recombinant plasmid containing blaKPC. The RPA-Cas13a assay demonstrated a sensitivity of 96.5% and specificity of 100% when tested on 57 blaKPC-positive CRE strains, which were confirmed by DNA sequencing. Moreover, in 311 sputum samples, the theoretical antibiotic resistance characteristics of blaKPC-positive strains obtained by the RPA-Cas13a assay were highly consistent with the results of antibiotic susceptibility test (Kappa = 0.978 > 0.81, P < 0.01). In conclusion, the RPA-Cas13a system is a simple and one-hour efficient technology for the detection of a potentially fatal antibiotic resistance gene.

Association of lifestyle habits and cardiovascular risk among sedentary adults.

This study aimed to analyze the association of lifestyle habits (physical activity, sleep habits, and eating habits) with cardiovascular risk (arterial stiffness and autonomic nervous system function) among sedentary adults. Sixty adults of sedentariness and physical activity were evaluated by accelerometers; sleep and eating habits were assessed by questionnaires; cardiovascular risks were assessed by pulse wave velocity (PWV), ankle-brachial index, flow mediated dilation, and heart rate variability; circulating biomarkers were also determined. Prolonged sitting (represented by longer maximum length of sedentary bouts, lower length of sedentary breaks, and more total time of sitting) were (P < .05) significantly associated with matrix metalloproteinases, neuropeptide Y, C-reactive protein, peptide Y, ghrelin, and leptin; significant associations (P < .05) were also observed of total time in physical activity with most circulating biomarkers except interleukin-6, tumor necrosis factor-α, and adiponectin. Sleep habits, especially sleep efficiency, were (P < .05) significantly associated with PWV, ankle-brachial index, and circulating biomarkers. Eating habits (including emotional overeating and enjoyment of food) were (P < .05) significantly associated with PWVs and flow mediated dilation; satiety responsiveness and enjoyment of food were (P < .05) significantly associated with low-frequency spectral component expressed in normalized units, high frequency spectral component expressed in normalized units, and ratio between low-frequency/high frequency spectral component expressed in normalized units. The findings indicated that several lifestyle habits among sedentary adults were closely associated with increased cardiovascular risk. Sedentary people were encouraged to live with sufficient physical activity, good sleep, and healthy eating habits for decreasing arterial stiffness and balancing autonomic nervous function.

The sensitivity of bone conduction for dental implants.

Dental implants are connected to the alveolar bone by osseointegration. Dental implants could be used as a potential bone conduction (BC) hearing assistive device in the mouth. However, the BC threshold of dental implants has not been reported. The present study aimed to examine the pure tone auditory thresholds of normal human subjects to BC stimulation of the implants. Dental implants showed a significantly lower BC threshold than natural teeth and mastoids. Mandibular dental implants had BC sensitivity similar to that of maxillary dental implants. The BC threshold of anterior dental implants was significantly lower than that of posterior dental implants. Dental implants exhibited excellent BC properties.

Pain assessment during physiotherapy and noxious stimuli in patients with disorders of consciousness: A preliminary study.

Objectives: The primary purpose of this study is to determine whether patients with disorders of consciousness (DOC) (unresponsive wakefulness syndrome, UWS; minimally conscious state, MCS) experience pain during physiotherapy and noxious stimuli in a larger patient population. Materials and methods: The patients' level of consciousness was measured with the Coma Recovery Scale-Revised (CRS-R). Additionally, the Nociception Coma Scale-revised (NCS-R) was used to assess their pain response. The NCS-R total scores between UWS and MCS at baseline, physiotherapy and noxious stimulus were compared using the Mann-Whitney U test (Wilcoxon rank-sum test) and the Kruskal-Wallis H test with Bonferroni correction. Results: The study enrolled 93 participants. There was a statistically significant difference in NCS-R total scores between the three conditions (H = 215.25, p < 0.001). At baseline, there was no statistically significant difference between MCS and UWS (U = 378, z = -1.35, p = 0.178). While there was a statistically significant difference between MCS and UWS during physiotherapy (U = 1,362, z = -3.06, p < 0.01) and under noxious stimuli (U = 5142.5, z = -11.22, p < 0.001). Conclusion: Physiotherapy improved the activity responsiveness of DOC patients, and patients experienced less potential pain. However, some DOC patients, especially MCS patients, perceived pain under the noxious stimuli.

Systematic analysis of prognostic and immunologic characteristics associated with coronavirus disease 2019 regulators in acute myeloid leukemia.

The coronavirus disease 2019 (COVID-19) pandemic has so far damaged the health of millions and has made the treatment of cancer patients more complicated, and so did acute myeloid leukemia (AML). The current problem is the lack of understanding of their interactions and suggestions of evidence-based guidelines or historical experience for the treatment of such patients. Here, we first identified the COVID-19-related differentially expressed genes (C-DEGs) in AML patients by analyzing RNA-seq from public databases and explored their enrichment pathways and candidate drugs. A total of 76 C-DEGs associated with the progress of AML and COVID-19 infection were ultimately identified, and the functional analysis suggested that there are some shared links between them. Their protein-protein interactions (PPIs) and protein-drug interactions were then recognized by multiple bioinformatics algorithms. Moreover, a COVID-19 gene-associated prognostic model (C-GPM) with riskScore was constructed, patients with a high riskScore had poor survival and apparently immune-activated phenotypes, such as stronger monocyte and neutrophil cell infiltrations and higher immunosuppressants targeting expressions, meaning which may be one of the common denominators between COVID-19 and AML and the reason what complicates the treatment of the latter. Among the study's drawbacks is that these results relied heavily on publicly available datasets rather than being clinically confirmed. Yet, these findings visualized those C-DEGs' enrichment pathways and inner associations, and the C-GPM based on them could accurately predict survival outcomes in AML patients, which will be helpful for further optimizing therapies for AML patients with COVID-19 infections.

Efficient Robust Yield Method for Preparing Bacterial Ghosts by Escherichia coli Phage ID52 Lysis Protein E.

Bacterial ghosts (BGs) are nonliving empty bacterial shells without cytoplasm retaining original morphology and identical antigenicity of natural bacteria, making them high potential and promising vaccine candidates and delivery vehicles. However, the low yield of commonly used BGs preparation methods limits its mass production and widely application. In order to improve BGs production, E. coli phage ID52 lysis protein E was introduced to generating BGs for the first time. Above all, we compared the lysis activity of lysis protein of E. coli phage φX174 and E. coli phage ID52 as well as the effects of promoters on the lysis activity of ID52-E, which shown that the lysis activity and BGs formation rate of protein ID52-E was significantly higher than protein φX174-E. Further, the lysis activity of ID52-E was significantly improved under the control of L-arabinose inducible promoter which initial induction OD600 reached as high as 2.0. The applicability of lysis protein ID52-E induced by L-arabinose was proved by preparing probiotic E. coli Nissle 1917 BGs and pathogenic Salmonella typhimurium BGs in mass production. This paper introduced a novel and highly efficient method for BGs preparation depending on recombinant expression of E. coli phage ID52-E under eco-friendly and reasonable price inducer L-arabinose.

Methimazole and α-lipoic acid as metallo-ß-lactamases inhibitors.

The emergence of bacterial resistance poses a serious threat to public health. One of the most important resistance mechanisms against ß-lactam antibiotics is the production of metallo-ß-lactamases (MBLs). In this study, α-lipoic acid (LA) and methimazole (MMI), which have been used in clinical practice as non-antibacterial drugs and as a supplement, were chosen to explore their potential to be metallo-ß-lactamases inhibitors (MBLIs). Enzyme inhibition assays showed that LA and MMI had moderate inhibitory activity against NDM-1 but no activity against VIM-2 and IMP-7. Antibacterial assays to determine synergy, demonstrated that the combination of LA or MMI with meropenem (MER) reduced the MIC value of MER against NDM-1 producing E. coli 16 times and 4 times, respectively, lower than that of MER alone. The fractional inhibitory concentration index (FICI) values were calculated to be less than 0.5, indicating that both LA and MMI had synergistic antibacterial effects with MER against all three MBLs expressing E. coli strains. The time-kill studies also suggested that LA and MMI were effective in restoring the antibacterial effect of MER. These findings revealed that LA and MMI are potential carbapenem enhancers, and provide a starting point for the development of potent MBLIs.

Linking human activities and global climatic oscillation to phytoplankton dynamics in a subtropical lake.

Human activities and climate change are two major stressors affecting lake ecosystems as well as phytoplankton communities worldwide. However, how the temporal dynamics of phytoplankton are directly or indirectly linked to anthropogenic activities and climatic oscillation remains unclear. We assessed the annual trends (1988-2018) in phytoplankton abundance (PA) in Lake Dongting, China and related it to five groups of variables characterizing human activities, global climate oscillation, water nutrients, hydrology, and meteorology. We found a significant increase in PA, urbanization (Upop), total nitrogen (TN), fertilizer application (FA), number of summer days (SU), and the warm speed duration index (WSDI) and a significant decrease in the water discharge of three inlets (TIWD) and the sediment discharge of three inlets (TISD) and four tributaries (FTSD) and the net sediment deposition (NSD). However, no significant annual trends were observed for the number of rainstorm days (R50mm), the simple precipitation intensity index (SDII) and yearly anomalies of El Niño-Southern oscillation events (ENSOi). Cross-correlation Function analyses demonstrated that the operation of the Three George Dam (TGD) strengthened the effects of hydrology, rainfall patterns and ENSOi on phytoplankton, but strongly weakened the association between water nutrients, human activities and phytoplankton abundance. Path analysis revealed that TP, TN, FA, R50 mm as well as WSDI had a direct positive effect on PA, while a direct negative effect was found for ENSOi, NSD and TISD. Human activities (Upop and FA), warming (WSDI and SU), and rainfall patterns (SDII and R50 mm) exerted indirect controls on phytoplankton through changes in water nutrients and hydrology. Climate change (ENSOi) had a direct effect on PA, but also showed twelve indirect pathways via changes in hydrology and meteorology (both positive and negative effects were found). Overall, meteorology contributed most markedly to the variations of PA (29.3%), followed by hydrology (25.3%), human activities (24%), water nutrients (10.5%), and ENSOi (1.9%). Our results highlight a strongly causal connection between human activities as well as global climate change and phytoplankton and the benefits of considering multiple environmental drivers in determining the temporal dynamics of lake biotic communities.

Association Between Aspartate Aminotransferase to Alanine Aminotransferase Ratio and Incidence of Type 2 Diabetes Mellitus in the Japanese Population: A Secondary Analysis of a Retrospective Cohort Study.

BACKGROUND: The study on the association between aspartate aminotransferase to alanine aminotransferase (AST/ALT) ratio and the risk of type 2 diabetes mellitus (T2DM) was limited. Therefore, we conducted a secondary analysis based on online data to explore whether there was an association between the AST/ALT ratio and incident T2DM among a large number of Japanese people. METHODS: The study was a retrospective cohort study. We downloaded the NAGALA (NAfld in Gifu area) data from DATADRYAD website between 2004 and 2015. This present study included 15,291 participants. Cox proportional-hazards regression, generalized additive models and subgroup analyses were used to find out the association between the AST/ALT ratio and T2DM events. RESULTS: The negative relationship was shown between AST/ALT ratio and incident T2DM (HR = 0.617, 95% CI: 0.405-0.938) in our study. A non-linear relationship and saturation effect were found between them, and the inflection point was 0.882. It indicated that the AST/ALT ratio was negatively correlated with incident T2DM when the AST/ALT ratio was less than the inflection point (HR = 0.287, 95% CI: 0.126-0.655, p = 0.0030). We found that exercise modified their relationship (P for interaction = 0.0024), and people who did not exercise associated strongly (HR = 0.464 95% CI: 0.290-0.741). CONCLUSION: AST/ALT ratio was negatively associated with T2DM risk, and their relationship was non-linear and had a saturation effect. When the AST/ALT ratio was less than 0.882, they showed a significant negative correlation.

Downregulation of MCM8 expression restrains the malignant progression of cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a highly aggressive malignant tumor with an extremely poor prognosis. Minichromosome maintenance 8 homologous recombination repair factor (MCM8) is a helicase involved in the elongation step of DNA replication and tumorigenesis. In the present study, the clinical significance and biological function of MCM8 in CCA were investigated. The expression levels of MCM8 in CCA and paracancerous tissues were analyzed using immunohistochemical staining. The potential mechanisms underlying MCM8 and the biological effects of MCM8 in CCA cells were explored using in vitro assays and in vivo mouse xenograft models. The high expression levels of MCM8 in CCA has important clinical significance in predicting disease progression. Knockdown of MCM8 decreased proliferation, promoted apoptosis and suppressed migration of CCA cells. MCM8 knockdown also suppressed tumor growth in vivo. Mechanistically, MCM8 knockdown led to the abnormal downregulation of survivin, XIAP, HSP27, IGF­1sR, sTNF­R1, sTNF­R2, TNF­α and TNF­ß. Furthermore, downregulation of MCM8 expression inhibited the PI3K/Akt signaling pathway and induced the MAPK9 signaling pathway. MCM8 promoted the malignant progression of CCA, indicating that inhibition of MCM8 may have the potential to serve as a novel molecular targeted therapy.

Desulfovibrio is not always associated with adverse health effects in the Guangdong Gut Microbiome Project.

Desulfovibrio (DSV) is frequently found in the human intestine but limited knowledge is available regarding the relationship between DSV and host health. In this study, we analyzed large-scale cohort data from the Guangdong Gut Microbiome Project to study the ecology of DSV and the associations of DSV and host health parameters. Phylogenetic analysis showed that Desulfovibrio piger might be the most common and abundant DSV species in the GGMP. Predominant sub-OTUs of DSV were positively associated with bacterial community diversity. The relative abundance of DSV was positively correlated with beneficial genera, including Oscillospira, Coprococcus,Ruminococcus,Akkermansia, Roseburia,Faecalibacterium, andBacteroides, and was negatively associated with harmful genera, such as Clostridium,Escherichia,Klebsiella, and Ralstonia. Moreover, the relative abundance of DSV was negatively correlated with body mass index, waist size, triglyceride levels, and uric acid levels. This suggests that DSV is associated with healthy hosts in some human populations.

Bioprinting of Human Cord Blood-Derived CD34+ Cells and Exploration of the Multilineage Differentiation Ability in Vitro.

The three-dimensional (3D) marrow microenvironment plays an essential role in regulating human cord blood-derived CD34+ cells (hCB-CD34+) migration, proliferation, and differentiation. Extensive in vitro and in vivo studies have aimed to recapitulate the main components of the bone marrow (BM) niche. Nonetheless, the models are limited by a lack of heterogeneity and compound structure. Here, we fabricated coaxial extruded core-shell tubular scaffolds and extrusion-based bioprinted cell-laden mesh scaffolds to mimic the functional niche in vitro. A multicellular mesh scaffold and two different core-shell tubular scaffolds were developed with human bone marrow-derived mesenchymal stromal cells (BMSCs) in comparison with a conventional 2D coculture system. A clear cell-cell connection was established in all three bioprinted constructs. Cell distribution and morphology were observed in different systems with scanning electron microscopy (SEM). Collected hCB-CD34+ cells were characterized by various stem cell-specific and lineage-specific phenotypic parameters. The results showed that compared with hCB-CD34+ cells cocultured with BMSCs in Petri dishes, the self-renewal potential of hCB-CD34+ cells was stronger in the tubular scaffolds after 14 days. Besides, cells in these core-shell constructs tended to obtain stronger differentiation potential of lymphoid and megakaryocytes, while cells encapsulated in mesh scaffolds obtained stronger differentiation tendency into erythroid cells. Consequently, 3D bioprinting technology could partially simulate the niche of human hematopoietic stem cells. The three models have their potential in stemness maintenance and multilineage differentiation. This study can provide initial effective guidance in the directed differentiation research and related screening of drug models for hematological diseases.

Long-term dynamic compression enhancement TGF-ß3-induced chondrogenesis in bovine stem cells: a gene expression analysis.

BACKGROUND: Bioengineering has demonstrated the potential of utilising mesenchymal stem cells (MSCs), growth factors, and mechanical stimuli to treat cartilage defects. However, the underlying genes and pathways are largely unclear. This is the first study on screening and identifying the hub genes involved in mechanically enhanced chondrogenesis and their potential molecular mechanisms. METHODS: The datasets were downloaded from the Gene Expression Omnibus (GEO) database and contain six transforming growth factor-beta-3 (TGF-ß3) induced bovine bone marrow-derived MSCs specimens and six TGF-ß3/dynamic-compression-induced specimens at day 42. Screening differentially expressed genes (DEGs) was performed and then analysed via bioinformatics methods. The Database for Annotation, Visualisation, and Integrated Discovery (DAVID) online analysis was utilised to obtain the Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment. The protein-protein interaction (PPI) network of the DEGs was constructed based on data from the STRING database and visualised through the Cytoscape software. The functional modules were extracted from the PPI network for further analysis. RESULTS: The top 10 hub genes ranked by their connection degrees were IL6, UBE2C, TOP2A, MCM4, PLK2, SMC2, BMP2, LMO7, TRIM36, and MAPK8. Multiple signalling pathways (including the PI3K-Akt signalling pathway, the toll-like receptor signalling pathway, the TNF signalling pathway, and the MAPK pathway) may impact the sensation, transduction, and reaction of external mechanical stimuli. CONCLUSIONS: This study provides a theoretical finding showing that gene UBE2C, IL6, and MAPK8, and multiple signalling pathways may play pivotal roles in dynamic compression-enhanced chondrogenesis.

A 3D engineered scaffold for hematopoietic progenitor/stem cell co-culture in vitro.

Proliferation of HPSCs in vitro can promote its broad clinical therapeutic use. For in vitro co-culture, interaction between the stem cell and feeder cell as well as their spatial position are essential. To imitate the natural microenvironment, a 3D engineered scaffold for CD34+ cells co-culture was established via 3D bioprinting. Herein, the concentration of hydrogel and the ratio of two kinds of cells were optimized. Flow cytometry, real time PCR and RNA-seq technology were applied to analyze the effect of the engineered scaffold on expanded cells. After 10 days co-culture with the engineered scaffold, the expansion of CD34+CD38- cells can reach 33.57-folds and the expansion of CD34+CD184+ cells can reach 16.66-folds. Result of PCR and RNA-seq indicates that the CD34+ cells in 3D group exhibited a tendency of interaction with the engineered scaffold. Compared to 2D co-culture, this customizable 3D engineered scaffold can provide an original and integrated environment for HPSCs growth. Additionally, this scaffold can be modified for different cell co-culture or cell behavior study.

High Oscillospira abundance indicates constipation and low BMI in the Guangdong Gut Microbiome Project.

Oscillospira is a common yet rarely cultivated gut bacterial genus. Recently human gut microbiota studies have demonstrated its underlying significance for host health. However, little is known about Oscillospira-related host information and the links between Oscillospira and other members of the gut microbial community. To study the ecology of Oscillospira and gain insights into Oscillospira-related host physiological conditions, we analyzed data from the Guangdong Gut Microbiome Project, one of the largest gut microbiota database currently. Data of 6376 participants were analyzed. We studied the prevalence and relative abundance of Oscillospira as well as the profiles of associated microbial communities. We found that Oscillospira is closely related to human health because its abundance was positively correlated with microbial diversity, high density lipoprotein, and sleep time, and was inversely correlated with diastolic blood pressure, systolic blood pressure, fasting blood glucose, triglyceride, uric acid and Bristol stool type. Moreover, random forest analysis with five-fold cross validation showed Oscillospira could be a predictor of low BMI and constipation in the subset. Overall, in this study, we provide a basic understanding of Oscillospira-related microbiota profile and physiological parameters of the host. Our results indicate Oscillospira may play a role in aggravating constipation.