Early autoimmunity and outcome in virus encephalitis: a retrospective study based on tissue-based assay.

To explore the autoimmune response and outcome in the central nervous system (CNS) at the onset of viral infection and correlation between autoantibodies and viruses. METHODS: A retrospective observational study was conducted in 121 patients (2016-2021) with a CNS viral infection confirmed via cerebrospinal fluid (CSF) next-generation sequencing (cohort A). Their clinical information was analysed and CSF samples were screened for autoantibodies against monkey cerebellum by tissue-based assay. In situ hybridisation was used to detect Epstein-Barr virus (EBV) in brain tissue of 8 patients with glial fibrillar acidic protein (GFAP)-IgG and nasopharyngeal carcinoma tissue of 2 patients with GFAP-IgG as control (cohort B). RESULTS: Among cohort A (male:female=79:42; median age: 42 (14-78) years old), 61 (50.4%) participants had detectable autoantibodies in CSF. Compared with other viruses, EBV increased the odds of having GFAP-IgG (OR 18.22, 95% CI 6.54 to 50.77, p<0.001). In cohort B, EBV was found in the brain tissue from two of eight (25.0%) patients with GFAP-IgG. Autoantibody-positive patients had a higher CSF protein level (median: 1126.00 (281.00-5352.00) vs 700.00 (76.70-2899.00), p<0.001), lower CSF chloride level (mean: 119.80±6.24 vs 122.84±5.26, p=0.005), lower ratios of CSF-glucose/serum-glucose (median: 0.50[0.13-0.94] vs 0.60[0.26-1.23], p=0.003), more meningitis (26/61 (42.6%) vs 12/60 (20.0%), p=0.007) and higher follow-up modified Rankin Scale scores (1 (0-6) vs 0 (0-3), p=0.037) compared with antibody-negative patients. A Kaplan-Meier analysis revealed that autoantibody-positive patients experienced significantly worse outcomes (p=0.031). CONCLUSIONS: Autoimmune responses are found at the onset of viral encephalitis. EBV in the CNS increases the risk for autoimmunity to GFAP.

Impact of water level fluctuations on the development of phytoplankton in a large subtropical reservoir: implications for the management of cyanobacteria.

Lake water level fluctuations (WLF) are an important factor driving the selection and seasonal dynamics of phytoplankton and potentially toxigenic cyanobacteria. Nevertheless, the relative importance of environmental drivers connected to WLF may be completely different, depending on the typology and use of waterbodies, latitude and climatic regimes. In this study, we investigated the impact of WLF in a large subtropical reservoir in south-eastern China (Hongfeng Reservoir, Guizhou Province). The study was based on monthly samplings carried out in 2014 in six stations. The strong increase in the water level observed in early summer caused a radical shift in the phytoplankton community. While in the pre-flooding period phytoplankton was composed of large diatoms, chrysophytes and Oscillatoriales (mostly Limnothrix sp.), the post-flooding period showed an increase in smaller and more competitive chlorophytes, smaller diatoms and cryptophytes better adapted to a fast colonisation of new and nutrient-rich environments. The environmental drivers that drove the change were dilution, flushing and interference with the seasonal water stratification processes. We concluded that, because WLF represents a complex variable integrating different physical effects in one explanatory descriptor, its value as a predictor of phytoplankton and cyanobacteria dynamics in lake ecosystems is difficult to generalise and needs to be investigated on a case-by-case basis. For this reason, considering the year-to-year hydrological variability that potentially characterise reservoirs, definite indications for management should be outlined considering more than 1-year study.

Changes in the structure of intestinal mucosal flora in colorectal cancer patients / 南方医科大学学报

OBJECTIVE@#To investigate the changes in bacterial flora in fecal samples, at the tumor loci and in adjacent mucosa in patients with colorectal cancer (CRC).@*METHODS@#We collected fecal samples from 13 patients with CRC and 20 healthy individuals and tumor and adjacent mucosa samples from 6 CRC patients. The differences in bacterial composition between the fecal and mucosa samples were analyzed with 16S rDNA sequencing and bioinformatics methods. We also detected the total number of bacteria in the feces using flow cytometry, isolated and identified the microorganisms in the fecal and mucosa samples using common bacterial culture media. We further tested the effects of 7 isolated bacterial strains on apoptosis of 3 CRC cell lines using lactate dehydrogenase detection kit.@*RESULTS@#The bacterial α-diversity in the feces of healthy individuals and in adjacent mucosa of CRC patients was significantly higher than that in the feces and tumor mucosa in CRC patients (P < 0.05). Lactobacillaceae is a specific bacteria in the feces, while Escherichia, Enterococcus, and Fusobacterium are specific bacteria in tumor mucosa of CRC patients as compared with healthy individuals. Cell experiment with3 CRC cell lines showed that Bacteroides fragilis isolated from the tumor mucosa of CRC patients produced significant inhibitory effects on cell proliferation (P < 0.0001), while the isolated strain Fusobacterium nucleatum obviously promoted the proliferation of the cell lines (P < 0.001).@*CONCLUSION@#The bacterial flora in the feces, tumor mucosa and adjacent mucosa of CRC patients is significantly different from that in the feces of healthy individuals, and the fecal flora of CRC patients can not represent the specific flora of the tumor mucosa. Inhibition of F. nucleatum colonization in the tumor mucosa and promoting B. fragilis colonization may prove beneficial for CRC treatment.

[Seasonal stratification and eutrophication characteristics of a deep reservoir, Longtan Reservoir in subtropical area of China].

In order to reveal the seasonal stratification and eutrophication characteristics of the subtropical large deep reservoir--Longtan Reservoir, the spatial and temporal distribution of environmental factors and eutrophic index were investigated during November (dry period) 2012, April (level period) and July (wet period) 2013. The results suggested that: (1) The stratification structure of Longtan Reservoir was meromictic lake, it had a single thermocline structure in the dry season, the surface layer to the 60 m was a mixomolimnion, 60-80 m was a thermocline, deeper more than 80 m was a monimolimnion. It had a double thermocline structure in flow period and wet period, the surface to 10 m was a mixed layer, 10-20 m was a thermocline, 20-40 m was a mixed layer, 40-60 m was a thermocline, deeper more than 60 m was a mixed layer. (2) The thermal stratification dominated the structure of other environmental factors, the stratification structure limited the water convection, especially the monimolimnion reduced the harm of the endogenous pollution. (3) The trophic level index (TLI) was 23.4-32.8 in the dry period, 27.1-38.6 in the flow period and 26.0-45.1 in the wet period, which were all Mesotropher. The trophic state index of total nitrogen was 60.3-72.5, which was eutropher to hyper eutropher, N: P was 107:1, which was phosphorus limited.

Effect and mechanism of aspirin combined with vinorelbine on non-small cell lung cancer / 中国中药杂志

The study aimed to investigate the effect and mechanism of aspirin combined with vinorelbine on the proliferation and apoptosis of non-small cell lung cancer cells. 3-(4-dimethylthiazolyl-2)-2-diphenyltetrazolium bromide(MTT) was used to detect the cytotoxic effect of aspirin and vinorelbine on H460 and A549 cells, and half of inhibitory concentration(IC_(50)) value of drugs as well as synergistic effect were calculated. The results showed that both aspirin and vinorelbine inhibited the cancer cells proliferation by a concentration-dependent manner with IC_(50 )values of 1.553 mmol·L~(-1) and 0.033 μmol·L~(-1) in H460 cells, respectively. The IC_(50 )values of aspirin and vinorelbine were 1.70 mmol·L~(-1)and more than 20 μmol·L~(-1) in A549 cells. The combination index(CI) value was used to evaluate the combined effect of two drugs. Aspirin combined with vinorelbine had synergistic effects at the ratio of 100∶1 on H460 cells and 1∶10 on A549 cells(CI<1). Clone formation and 4',6-diamidino-2-phenylindole(DAPI)/propidium iodide(PI) staining assays were used to verify the effect of the combination of two drugs on proliferation of H460 cells. Compared with the aspirin single group, the combination group had stronger inhibitory effect on the proliferation of H460 cells and the clone formation rate was 49.5%(P<0.05). Furthermore, apoptosis, mitochondrial membrane potential, reactive oxygen species and Western blot experiments were used to explore the synergistic mechanism of aspirin combined with vinorelbine in inhibiting cell proliferation. The results showed that the cancer cell apoptosis rate was 52.8%, the mitochondrial membrane potential was decreased to 33.1%, and the levels of reactive oxygen species was increased to 73.3% in combination group, which were significantly different from those of the single drug treatment groups(P<0.05). Western blot showed that combination group significantly up-regulated the expressions of Bax, p53, cleaved caspase-3 and cytochrome C, while down-regulated the expression of anti-apoptosis proteins such as Bcl-xL and Bcl-2 when compared with single groups. Our results suggested that aspirin combined with vinorelbine could synergistically inhibit the proliferation of H460 cells by inducing the cell apoptosis through the mitochondrial pathway.

Preparation and evaluation of novel purine derivative F7 thermosensitive liposome / 国际药学研究杂志

Objective To prepare F7 thermosensitive liposome and evaluate its physicochemical properties, then investigate its cytotoxicity against tumor cells in vitro. Methods The F7 thermosensitive liposome was prepared by the pH gradient active drug loading method using dipalmitoyl phosphatidylcholine myristoyl lyso-phosphocholine and 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy (polyethylene glycol)-2000 as membrane materials. The encapsulation efficiency and drug loading were determined for the F7 thermosensitive liposome by HPLC. The phase transition temperature of F7 thermosensitive liposome was investigated by differential scanning calorimetry;the liposome morphology was observed by atomic force microscopy;the drug release of liposome was examined by dialysis;and the particle size and zeta potential were measured through Malvern particle size analyzer. The cytotoxicity of F7 and F7 thermosensitive liposome was determined by the MTT method, and the freeze-drying process was optimized using the designexpert software. Results The encapsulation efficiency of F7 thermosensitive liposomes was (97.56±0.22) ％, and the drug loading ratio was (1.51±0.01) ％. The phase transition temperature of F7 thermosensitive liposome was 39.9℃, the zeta potential was (-15.10±0.85) mV, the particle size was (86.94±1.21) nm, and the poly disperse coefficient was 0.17±0.01. Compared with the F7 injection, the F7 thermosensitive liposomes showed a stronger, dose-dependent inhibitory effect on the growth of lung cancer H1299 and breast cancer MCF-7 cells. The freeze-dried powder of liposomes dissolved well with the encapsulation efficiency of 95％ and the particle size of approximately 130 nm. Conclusion The F7 thermosensitive liposome prepared by the pH gradient active drug loading method has high encapsulation efficiency and good stability. The preparation method is simple and feasible for further development of the F7 preparation.