[Pathogenic detection and molecular tracing of a bacillary dysentery outbreak by Shigella sonnei in Huainan city].

Objective: To understand the virulence gene and drug resistance profile of Shigella sonnei outbreak in Huainan city, and conduct pathogenic traceability analysis. Methods: Water samples and feces related to an infectious diarrhea outbreak in Huainan city in August 2020 were collected for multiple pathogen detection. Virulence gene, drug sensitivity, pulse-field gel electrophoresis and whole genome sequencing of Shigella isolates were analyzed respectively. Results: 38 strains of Shigella sonnei were detected in 56 samples of mucilage feces with a positive rate 67.86%, and all serotypes were Shigella sonnei Phase I. Three strains of Shigella sonnei were detected by fluorescence PCR in the Gram-negative (GN) bacterial enrichment solution of terminal water and well water. Virulence genes were ipaH positive (38), ipaH/ial (31) and ipaH/ial/sen positive (1), respectively. The drug resistance spectrum showed that 9 of 14 antibiotics were 100% resistant, and only imipenem, chloramphenicol, ceftazidime and ciprofloxacin were effective drugs. XbaⅠ restriction enzyme map type of 36 isolates was completely consistent, and the ST type analysis of 3 strains was ST152. Whole genome sequencing and analysis verified that the outbreak was caused by a single clonal group of strains, and revealed that the isolates of the outbreak were clustered into a large cluster with 3 Chinese strains and 1 Korean strain in the database, far away from the strains of other countries. Conclusion: The outbreak is caused by a single clone of Shigella sonnei, which are low virulence strains and have multiple drug resistance.

[Influence of genetic variation of programmed death-ligand 1 (PD-L1) on the prognosis of patients with non-small cell lung cancer who received platinum-based adjuvant chemotherapy].

Objective: The aim of present study was to investigate the influence of genetic variation of programmed death-ligand 1 (PD-L1) on the prognosis of patients with non-small cell lung cancer (NSCLC) who received platinum-based adjuvant chemotherapy. Methods: This study was designed as a retrospective analysis, and a total of 278 patients with postoperative NSCLC who received platinum-based adjuvant chemotherapy from January 2012 to December 2018 in the Department of Respiratory Medicine of the First affiliated Hospital of Zhengzhou University were included in this study. Biological specimens of the patients were collected during hospitalization. Recurrence status and adverse reactions were evaluated in the hospital during adjuvant chemotherapy. Survival data of the patients were obtained through telephone follow-up after completing the fixed cycle of adjuvant chemotherapy. DNA extracted from the collected hematological specimens was genotyped for PD-L1 gene polymorphism. Additionally, postoperative cancer tissue specimens from 68 patients were collected for RNA extraction in order to perform the PD-L1 mRNA expression analysis. The univariate analysis of genotypes and prognosis was carried out by Kaplan-Meier survival analysis. Results: Prognostic results indicated that the median disease-free survival (DFS) of the 278 patients with NSCLC was 3.2 years and the median overall survival (OS) was 4.9 years. The prevalence of -1813G>C polymorphism were: GG genotype 173 cases (62.23%), GC genotype 92 cases (33.09%), CC genotype 13 cases (4.68%), the minor allele frequency was 0.21, the distribution of the three genotypes was in accordance with Hardy-Weinberg Equilibrium (P=0.864). In view of the rare frequency of CC genotype, GC and CC genotype were merged in the following analysis. The survival analysis results of the two genotype groups suggested that the median DFS of patients with GG and GC/CC genotype was 2.7 and 4.0 years, which was statistically significant (P=0.013). Furthermore, the median OS of patients with GG and GC/CC was 4.0 and 5.4 years respectively, which was statistically significant as well (P=0.009). However, the safety analysis failed to find the significant association between the polymorphism and adverse events (P>0.05). Interestingly, expression analysis of RNA extracted from cancer tissues specimens indicated that the PD-L1 mRNA expression of the patients with GG genotype were significantly higher than those of the GC/CC genotype (3.67±0.65 vs 2.69±0.78, P<0.001). Conclusion: The prognosis of patients with postoperative non-small cell lung cancer who received platinum-based adjuvant chemotherapy is influenced by -1813G>C polymorphism of PD-L1 gene.

Neurobiological mechanisms of TENS-induced analgesia.

Pain inhibition by additional somatosensory input is the rationale for the widespread use of Transcutaneous Electrical Nerve Stimulation (TENS) to relieve pain. Two main types of TENS produce analgesia in animal models: high-frequency (∼50-100 Hz) and low-intensity 'conventional' TENS, and low-frequency (∼2-4 Hz) and high-intensity 'acupuncture-like' TENS. However, TENS efficacy in human participants is debated, raising the question of whether the analgesic mechanisms identified in animal models are valid in humans. Here, we used a sham-controlled experimental design to clarify the efficacy and the neurobiological effects of 'conventional' and 'acupuncture-like' TENS in 80 human volunteers. To test the analgesic effect of TENS we recorded the perceptual and brain responses elicited by radiant heat laser pulses that activate selectively Aδ and C cutaneous nociceptors. To test whether TENS has a long-lasting effect on brain state we recorded spontaneous electrocortical oscillations. The analgesic effect of 'conventional' TENS was maximal when nociceptive stimuli were delivered homotopically, to the same hand that received the TENS. In contrast, 'acupuncture-like' TENS produced a spatially-diffuse analgesic effect, coupled with long-lasting changes both in the state of the primary sensorimotor cortex (S1/M1) and in the functional connectivity between S1/M1 and the medial prefrontal cortex, a core region in the descending pain inhibitory system. These results demonstrate that 'conventional' and 'acupuncture-like' TENS have different analgesic effects, which are mediated by different neurobiological mechanisms.

Treatment of vitiligo with 308-nm excimer laser: our experience from a 2-year follow-up of 979 Chinese patients.

BACKGROUND: The 308-nm excimer laser had been proved to be a time-efficient and potent therapeutic alternative for the management of vitiligo. Different results had been reported in different ethnic populations. OBJECTIVE: To investigate the efficacy and related contributing factors of 308-nm excimer laser in Chinese vitiligo patients. METHODS: A total of 979 Chinese patients (3478 lesions) with progressive-stage vitiligo who had received 308-nm excimer laser treatment were recruited from the vitiligo clinic of Shandong Provincial Hospital of Dermatology &Venereology from 2012 to 2014. Efficacy of treatment was evaluated at the end of session by two independent dermatologists based on the before and after images taken. Repigmentation was graded on a 4-point scale: grade 1, poor repigmentation (0-25%); grade 2, moderate repigmentation (26-50%); grade 3, good repigmentation (51-75%); grade 4, excellent repigmentation (76-100%). RESULTS: The mean grade of repigmentation was 2.29, 44.22% showed less than 25% repigmentation, 16.27% showed 26-50% repigmentation, 5.95% showed 51-75% repigmentation and 33.55% showed more than 76% repigmentation. The repigmentation of facial lesions was better than lesions located elsewhere (P < 0.0001), the best response was noted in the periorbital region, while lesions on hands and feet showed poor repigmentation (P < 0.0001). The degree of repigmentation was negatively correlated with disease duration (r = -0.268, P < 0.001), age (r = -0.095, P < 0.001) and shape of lesions (r = -0.114, P < 0.001), whereas it was positively correlated with treatment frequency (r = 0.270, P < 0.001). Lesions with concurrent poliosis were more likely resistant to treatments. CONCLUSION: 308-nm excimer laser appears to be an effective and safe treatment in Chinese vitiligo patients. The clinical response and treatment efficacy was affected by many factors such as age, affected anatomical area, shape of the lesion, disease duration and treatment frequencies.

CARD9 mutation linked to Corynespora cassiicola infection in a Chinese patient.

Corynespora cassiicola is a plant pathogen associated with leaf-spotting disease. The fungus has been found on diverse substrates: leaves, stems and roots of plants; nematode cysts and human skin. It rarely causes human infections. Here we report one case of subcutaneous phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis in a woman. All of her clinical features pointed towards a genetic linkage. Hence, whole-exome sequencing and Sanger sequencing were performed on this patient. One mutation of CARD9 was detected.

Relationship between UV-irradiated HaCaT cell cytokines and Th1/Th2 imbalance.

We have previously found that an imbalance of Tc1/Tc2 T cell subtypes in vivo impacts the development of photodermatitis. The aim of this study was to investigate the relationship between cytokines derived from keratinocytes exposure to UV and the imbalance of Th subgroups. We used different doses of UVA and UVB to irradiate HaCaT cells. Twelve hours after irradiation, the expression of IL-10R, IL-4R, IL-12R, and IFN-γR proteins was observed using the S-P method, and the percentage of positive cells calculated. Protein levels of the respective ligands in the supernatant was measured by ELISA. Our results showed low levels of expression of the interrogated proteins in unirradiated HaCaT cells, and little or no expression could be detected in the supernatant. Little or no expression was also observed for IL-12R and IFN-γR 12 h after UVA or UVB irradiation. However, the expression of IL-10R and IL-10 was upregulated 12 h following UVB irradiation, as well as following lower dose UVA irradiation. In contrast, higher dose UVA decreased the expression of IL-10R and IL-10. The expression of IL-4R was increased following high doses of UVA and UVB irradiation, whereas no expression was observed after lower dose UV exposure. There was no change in IL-4 secretion into the supernatant. Our results demonstrate that the effects of UV exposure on keratinocyte-derived cytokines are different according to the doses of irradiation and the types of cytokines, and suggest that keratinocyte-derived cytokines after UV exposure might cause an imbalance of Th1/Th2.

HLA-B*13:01 and the dapsone hypersensitivity syndrome.

BACKGROUND: Dapsone is used in the treatment of infections and inflammatory diseases. The dapsone hypersensitivity syndrome, which is associated with a reported mortality of 9.9%, develops in about 0.5 to 3.6% of persons treated with the drug. Currently, no tests are available to predict the risk of the dapsone hypersensitivity syndrome. METHODS: We performed a genomewide association study involving 872 participants who had received dapsone as part of multidrug therapy for leprosy (39 participants with the dapsone hypersensitivity syndrome and 833 controls), using log-additive tests of single-nucleotide polymorphisms (SNPs) and imputed HLA molecules. For a replication analysis, we genotyped 24 SNPs in an additional 31 participants with the dapsone hypersensitivity syndrome and 1089 controls and performed next-generation sequencing for HLA-B and HLA-C typing at four-digit resolution in an independent series of 37 participants with the dapsone hypersensitivity syndrome and 201 controls. RESULTS: Genomewide association analysis showed that SNP rs2844573, located between the HLA-B and MICA loci, was significantly associated with the dapsone hypersensitivity syndrome among patients with leprosy (odds ratio, 6.18; P=3.84×10(-13)). HLA-B*13:01 was confirmed to be a risk factor for the dapsone hypersensitivity syndrome (odds ratio, 20.53; P=6.84×10(-25)). The presence of HLA-B*13:01 had a sensitivity of 85.5% and a specificity of 85.7% as a predictor of the dapsone hypersensitivity syndrome, and its absence was associated with a reduction in risk by a factor of 7 (from 1.4% to 0.2%). HLA-B*13:01 is present in about 2 to 20% of Chinese persons, 1.5% of Japanese persons, 1 to 12% of Indians, and 2 to 4% of Southeast Asians but is largely absent in Europeans and Africans. CONCLUSIONS: HLA-B*13:01 was associated with the development of the dapsone hypersensitivity syndrome among patients with leprosy. (Funded by the National Natural Science Foundation of China and others.).

Dietary supplementation with Lactobacillus fermentum I5007 improves the anti-oxidative activity of weanling piglets challenged with diquat.

AIMS: To determine the effects of Lactobacillus fermentum I5007 on the redox state of piglets oxidatively stressed with diquat. METHODS AND RESULTS: Twenty-four, 28-day-old barrows were used in a 2 × 2 factorial design experiment with the main effects being Lact. fermentum supplementation and diquat challenge. Half of the pigs (n = 12) were orally administered with 20 ml of a solution containing 10(8 ) CFU ml(-1) of Lact. fermentum each morning of the 21-day trial, while the remainder received saline. On day 8, these two groups were further subdivided so that half of the pigs in each group (n = 6) were intraperitoneally injected with 10 mg kg(-1) BW diquat, while the remainder received saline. The diquat-injected pigs had significantly poorer performance and increased levels of plasma cortisol, adrenaline, carbonyl and malondialdehyde. Lactobacillus fermentum supplementation significantly increased superoxide dismutase and glutathione and increased the ability to inhibit superoxide anion production in liver and muscle. CONCLUSIONS: Lactobacillus fermentum improved the anti-oxidative defence system and alleviated damage caused by diquat. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus fermentum has the potential to alleviate oxidative stress and improve weaning pig performance.

Analysis of the differentially expressed genes in Microsporum canis in inducing smooth skin and scalp tissue conditions.

Microsporum canis is a common zoophilic dermatophyte, which causes a range of infections. To explore the pathogenic mechanism of tinea capitis, we used the suppression subtractive hybridization (SSH) technique to investigate the differences in gene expression between different cultures of Microsporum canis incubated on three different types of mineral media containing child glabrous skin, child scalp tissue and adult scalp tissue. Using dot-blot hybridization and real-time PCR technique, we successfully screened and identified a pair of genes that had expression levels 44.6 and 117 times higher in culture 1 (M. canis cultured in mineral medium with child scalp tissue) than in culture 2 (M. canis cultured in mineral medium with glabrous skin tissue), and another pair of genes with expression levels 78.2 and 9.8 times higher in culture 1 than in culture 3 (M. canis cultured in mineral medium with adult scalp tissue). These four genes were found to have 41%, 53%, 40% and 94% homology to those encoding a hypothetical protein [family of serine hydrolases 1; (FSH1)], PQ loop repeat protein (PQ-LRP), a predicted protein [porphyrin galactose 4; (P-GAL4)] and NADH dehydrogenase subunit (NADH)1, respectively. The upregulation of the FSH1, PQ-LRP, P-GAL4 and NADH1 genes in cultures of child scalp tissue indicates that they are essential in the pathogenesis of tinea capitis caused by M. canis.

Identification of two novel splice mutations of the ADAR1 gene in two Chinese families with dyschromatosis symmetrica hereditaria.

Dyschromatosis symmetrica hereditaria (DSH) is a rare, autosomal dominant dermatosis, characterized by a mixture of hyperpigmented and hypopigmented macules on the dorsa of the hands and feet. The DSH locus has been mapped to chromosome 1q21, and in 2003, pathogenic mutations were identified in the ADAR1 (adenosine deaminase acting on RNA1) gene. In this study, we performed mutation detection of the ADAR1 gene in two Chinese families with DSH. PCR and direct sequencing of the ADAR1 gene were used to identify and confirm the mutations in the two families. Furthermore, we analysed the RNA transcripts by reverse transcriptase (RT)-PCR. Two aberrant splice products were confirmed with RT-PCR and DNA direct sequence analysis. These novel findings further extend our understanding of the role of ADAR1 in DSH.

Up-regulation of CXC chemokine receptor 4 expression in chronic atrial fibrillation patients with mitral valve disease may be attenuated by renin-angiotensin system blockers.

This study characterized CXC chemokine receptor 4 (CXCR4) expression in patients with mitral valve disease and chronic atrial fibrillation (AF). Forty-eight patients with chronic AF formed two groups based on whether they were treated with or without renin-angiotensin system (RAS) blockers (AF + RAS group; n = 25, or AF - RAS group; n = 23). The controls comprised 17 mitral valve disease patients with sinus rhythm (SR group). CXCR4 mRNA and protein levels in the left atria were significantly higher in the AF - RAS and AF + RAS groups than in the SR group. CXCR4 expression was significantly lower in the AF + RAS group than the AF - RAS group. More CD34(+) cells expressed CXCR4 in the AF - RAS and AF + RAS groups than in the SR group. Angiotensin II, collagen I and left atrial diameter significantly positively correlated with CXCR4 expression in the AF - RAS group. These results suggest that CXCR4 expression is up-regulated in chronic AF patients with mitral valve disease, is associated with atrial remodelling, and that these effects are attenuated by RAS blockers.

Resveratrol reduces endothelial progenitor cells senescence through augmentation of telomerase activity by Akt-dependent mechanisms.

BACKGROUND AND PURPOSE: Recent studies have shown that resveratrol increased endothelial progenitor cells (EPCs) numbers and functional activity. However, the mechanisms remain to be determined. Previous studies have demonstrated that increased EPC numbers and activity were associated with the inhibition of EPC senescence, which involves activation of telomerase. Therefore, we investigated whether resveratrol inhibits the onset of EPC senescence through telomerase activation, leading to potentiation of cellular activity. EXPERIMENTAL APPROACH: After prolonged in vitro cultivation, EPCs were incubated with or without resveratrol. The senescence of EPCs were determined by acidic beta-galactosidase staining. The bromo-deoxyuridine incorporation assay or a modified Boyden chamber assay were employed to assess proliferative or migratory capacity, respectively. To further examine the underlying mechanisms of these effects, we measured telomerase activity and the phosphorylation of Akt by western blotting. KEY RESULTS: Resveratrol dose dependently prevented the onset of EPCs senescence and increased the proliferation and migration of EPCs. The effect of resveratrol on senescence could not be abolished by eNOS inhibitor or by an oestrogenic receptor antagonist. Resveratrol significantly increased telomerase activity and Akt phosphorylation. Pre-treatment with the PI3K inhibitor, LY294002, significantly attenuated resveratrol-induced telomerase activity. CONCLUSIONS AND IMPLICATIONS: Resveratrol delayed the onset of EPC senescence and this effect was accompanied by activation of telomerase through the PI3K-Akt signalling pathway. The inhibition of EPCs senescence by resveratrol might protect EPCs against dysfunction induced by pathological factors in vivo and improve EPC functional activities in a way that may be important for cell therapy.