Polyhedral oligomeric silsesquioxane (POSS)-silicon/carbon quantum dots nanocomposites for cell imaging.

Silicon quantum dots (SiQDs) and carbon quantum dots (CQDs) are renowned for their outstanding applications in fluorescence imaging and biosensing. However, their small size poses significant challenges in terms of preparation, collection, and purification. Polyhedral oligomeric silsesquioxanes (POSS), an organic-inorganic nanohybrid with a cage-like structure, has recently attracted considerable attention due to its excellent biocompatibility. In this research, we utilize the encapsulating properties of POSS to improve the optical property of SiQDs/CQDs through an in situ synthesis strategy, resulting in the production of blue-emitting POSS-SiQDs, green-emitting POSS-G-CNDs, and red-emitting POSS-R-CNDs. By examining their structural and optical characteristics, it is found that these hybrid materials exhibit excellent luminescent properties, biocompatibility and cell membrane permeability. This facilitates multicolor intracellular imaging and underscores their successful application in biological imaging. Our study presents a novel approach to synthesize POSS-QDs composite nanomaterials with new perspectives in biological imaging and medical diagnostics.

Effect of alprostadil plus cilostazol on the treatment outcomes and inflammatory factors in patients with lower extremity arteriosclerosis obliterans receiving evidence-based care.

This study aims to elucidate the effect of alprostadil (ALP) plus cilostazol (CIL) on the treatment outcomes and inflammatory factors in patients with lower extremity arteriosclerosis obliterans (LEASO) receiving evidence-based care. Firstly, 130 patients with LEASO were selected from February 2020 to February 2023 and then randomly divided into two groups with 65 patients each. Excluding the dropouts, 59 patients in the control group (6 cases of dropout) received ALP and 62 patients in the research group (3 cases of dropout) received ALP plus CIL. Both groups were cared for in accordance with the evidence-based care model. Treatment outcomes, arteriosclerosis indexes (blood flow of dorsalis pedis artery [DPA], ankle-brachial index [ABI] and toe-brachial index [TBI]), hemorheological parameters (erythrocyte aggregation index [EAI], erythrocyte deformation index [EDI], high blood viscosity [HBV] and haematocrit [HCT]), inflammatory factors (interleukin [IL]-6, IL-8 and tumour necrosis factor [TNF]-α) and complications (nausea, diarrhoea, headache and transaminase elevation) were compared between the control and research groups. Results show that the overall response rate was markedly higher in the research group (90.32%) than in the control group (74.58%). Additionally, the blood flow of DPA, ABI and TBI in the research group significantly increased after the treatment and were higher than those in the control group. Meanwhile, the EAI, EDI, HBV, HCT, IL-6, IL-8 and TNF-α were significantly lower. The two groups did not differ markedly in the complication rate. The above findings suggest that ALP plus CIL is effective for patients with LEASO receiving evidence-based care. It can significantly improve arteriosclerosis indexes and hemorheological parameters while inhibiting serum inflammatory responses, with some certain safety.

Vertical and horizontal assemblage patterns of bacterial communities in a eutrophic river receiving domestic wastewater in southeast China.

Bacterial communities in rivers receiving untreated domestic wastewater may show specific spatial assemblage patterns due to a wide range of physicochemical conditions created by periodic algal bloom. However, there are significant gaps in understanding environmental forces that drive changes in microbial assemblages in polluted rivers. In this study, we applied high-throughput sequencing of 16S rRNA gene amplicons to perform comprehensive spatio-temporal profiling of bacterial community structure in a local river segment receiving domestic wastewater discharge in southeast China. Multivariate statistics were then used to analyse links between bacterial community structure and environmental factors. Non-metric multidimensional scaling (NMDS) plots showed that the bacterial community structure was different between upstream and downstream sections of the river. While the upstream water contained a high proportion of bacteria degrading xenobiotic aromatic compounds, the downstream water experiencing stronger algal bloom had a more diverse bacterial community which included the genus Aeromonas comprising 14 species, most of which are human pathogens. Least discriminant analysis (LDA) effect size revealed that the surface water was mainly inhabited by aerobic microorganisms capable of degrading aromatic compounds, and also contained bacterial genera including pathogenic species. In contrast, in the bottom water we found, along with aromatic compound-degrading species, anaerobic denitrifiers and Fe3+-reducing and fermentative bacteria. Variance partitioning canonical correspondence analysis (VPA) showed that nutrient ratios had a stronger contribution to bacterial dissimilarities than other major physicochemical factors (temperature, pH, dissolved oxygen, total organic carbon, and chlorophyll a). These results show that microbial communities in rivers continuously receiving domestic wastewater have specific longitudinal and vertical assemblage patterns and may contain pathogenic species presenting a high threat to public health. These factors should be taken into consideration while developing pollution management strategies.

Bacterial community associated with the intestinal tract of Chinese mitten crab (Eriocheir sinensis) farmed in Lake Tai, China.

Chinese mitten crab (CMC, Eriocheir sinensis) is an economically valuable species in South-East Asia that has been widely farmed in China. Characterization of the intestinal bacterial diversity of CMC will provide insights into the aquaculturing of CMCs. Based on the analysis of cloned 16S rRNA genes from culture-independent CMC gut bacteria, 124 out of 128 different clones reveal ＞95% nucleotide similarity to the species belonging to the four phyla of Tenericutes, Bacteroidetes, Firmicutes and Proteobacteria; one clone shows 91% sequence similarity to the member of TM7 (a candidate phylum without cultured representatives). Fluorescent in situ hybridization also reveals the abundance of Bacteroidetes in crab intestine. Electron micrographs show that spherical and filamentous bacteria are closely associated with the microvillus brush border of the midgut epithelium and are often inserted into the space between the microvilli using a stalk-like cell appendage. In contrast, the predominant rod-shaped bacteria in the hindgut are tightly attached to the epithelium surface by an unusual pili-like structure. Both 16S rRNA gene denaturing gel gradient electrophoresis and metagenome library indicate that the CMC Mollicutes group 2 appears to be present in both the midgut and hindgut with no significant difference in abundance. The CMC Mollicutes group 1, however, was found mostly in the midgut of CMCs. The CMC gut Mollicutes phylotypes appear to be most closely related to Mollicutes symbionts detected in the gut of isopods (Crustacea: Isopoda). Overall, the results suggest that CMCs harbor diverse, novel and specific gut bacteria, which are likely to live in close relationships with the CMC host.