Gut microbiota composition and bone mineral loss-epidemiologic evidence from individuals in Wuhan, China

We explored the association between gut microbiota composition and bone mineral loss in Chinese elderly people by high-throughput 16S ribosomal RNA (rRNA) gene sequencing. Compared with controls, a smaller number of operational taxonomic units (OTUs), several taxa with altered abundance, and specific functional pathways were found in individuals with low-bone mineral density (BMD).

INTRODUCTION

Gut microbiota plays important roles in human health and associates with a number of diseases. However, few studies explored its association with bone mineral loss in human.

METHODS

We collected 102 fecal samples from each eligible individual belonging to low-BMD and control groups for high-throughput 16S rRNA gene sequencing.

RESULTS

The low-BMD individuals had a smaller number of OTUs and bacterial taxa at each level. At the phylum level, Bacteroidetes were more abundant in the low-BMD group; Firmicutes were enriched in the control group; Firmicutes and Actinobacteria positively correlated and Bacteroidetes negatively correlated with the BMD and T-score in all subjects. At the family level, the abundance of Lachnospiraceae in low-BMD individuals reduced and positively correlated with BMD and T-score; meanwhile, BMD increased with increasing Bifidobacteriaceae. At the genus level, low-BMD individuals had decreased proportions of Roseburia compared with control ones (P < 0.05). Roseburia, Bifidobacterium, and Lactobacillus positively correlated with BMD and T-score. Furthermore, BMD increased with rising abundance of Bifidobacterium. Functional prediction revealed that 93 metabolic pathways significantly differed between the two groups (FDR-corrected P < 0.05). Most pathways, especially pathways related to LPS biosynthesis, were more abundant in low-BMD individuals than in control ones.

CONCLUSIONS

Several taxa with altered abundance and specific functional pathways were discovered in low-BMD individuals. Our findings provide novel epidemiologic evidence to elucidate the underlying microbiota-relevant mechanism in bone mineral loss and osteoporosis.

Risk factors of hemorrhagic transformation after intravenous thrombolysis with rt-PA in acute cerebral infarction

BACKGROUND

Intravenous thrombolysis is considered to be the standard reperfusion therapy for acute ischemic stroke, but its application is limited by high risk of hemorrhagic transformation (HT) after thrombolysis.

AIM

This study aimed to identify risk factors of HT after intravenous thrombolysis.

METHODS

Patients with acute ischemic stroke receiving rt-PA thrombolysis from February 2013 to January 2018 were retrospectively reviewed. They were divided into HT group and non-HT group based on cranial computed tomography. Data of all patients were collected and analysed by univariate analysis and stepwise logistic regression analysis.

RESULTS

A total of 403 patients were enrolled and their age ranged from 13 to 86 years, with an average age of 67.01 ± 31.88 years. 136 (33.7%) patients were females. The average time from disease onset to thrombolysis was 52.05 ± 20.12 min, and 46 patients (11.4%) had HT after thrombolysis. We found significant differences in activated partial thromboplastin time, fibrinogen value, platelet value and smoking before thrombolysis between HT and non-HT group (P < 0.05).

CONCLUSION

Smoking, prolongation of activated partial thromboplastin time, low fibrinogen levels and low platelet counts are associated with the risk of HT and could help the selection of thrombolytic patients to avoid HT.

[Comparison of intraocular pressure reduction in eyes with different intraocular tamponades after pars plana vitrectomy by 20% mannitol]

Objective: To investigate the efficacy of 20% mannitol in reducing intraocular pressure (IOP) in eyes with different intraocular tamponades after pars plana vitrectomy (PPV). Methods: Retrospective case-control study. Sixty-eight patients were administered with 20% mannitol and IOP was noted at regular intervals after simple PPV with ocular hypertension, including 24 males (26 eyes) and 44 females (46 eyes), aged (45.6±19.3) years. These cases were divided into three groups according to different tamponades: silicon-oil tamponade, 23 eyes; gas tamponade, 30 eyes; balanced salt solution (BSS), 19 eyes. The data were analyzed using the t test, variance and q test. Results: There was a significant decrease in IOP in all patients after using 20% mannitol. The IOP in the group of silicon-oil decreased from (33.25±2.56) mmHg (1 mmHg=0.133 kPa) to (23.21±1.85) mmHg, with a maximum decrease of 30.10%; the reduction in the group of C(3)F(8) was from (33.25±2.84) mmHg to (12.15±1.12) mmHg, with a maximum decrease of 33.44%. The IOP of the two groups dropped to a minimum both at 75 minutes. In the group of BSS, the IOP decreased from (32.95±2.33) mmHg to (17.50±1.35) mmHg, and the maximum extent of the decrease was 45.82% at 45 minutes. The difference in the IOP among the three groups at 20 min, 30 min, 45 min and 60 min was statistically significant (F=34.02, 112.68, 122.07, 34.83, all P=0.00). There were significant differences between the BSS group and the silicone-oil group (q=6.44, 13.04, 15.00, 17.11, all P=0.00), and between the BSS group and the C(3)F(8) group (q=7.68, 12.56, 12.93, 13.61, all P=0.00). Conclusion: In eyes with different intraocular tamponades, 20% mannitol was useful for short-term IOP reduction after vitrectomy, especially in those with BSS within one hour. But after 75 minutes, there was no statistically significant difference between groups. (Chin J Ophthalmol, 2019, 55:289-293).

Three species of Aeromonas (A. dhakensis, A. hydrophila and A. jandaei) isolated from freshwater crocodiles (Crocodylus siamensis) with pneumonia and septicemia

Hundreds of farmed Siamese crocodiles (Crocodylus siamensis) died during July 2016 at a farm in Wenchang, Hainan, China. In two necropsied crocodiles, we observed symptoms of dermatorrhagia, hepatomegaly and hepatic congestion. Pulmonitis was diagnosed by pulmonary congestion and pulmonary fibrinous exudate. Septicaemia was diagnosed by isolation of three Aeromonas species from blood and visceral tissues; A. dhakensis, A. hydrophila and A. jandaei were identified by biochemical and molecular tests. We used a zebrafish model to determine the half-maximal lethal dose (LD₅₀ ), and A. dhakensis was found to be the most virulent species, with an LD₅₀ of 8·91 × 10⁵ CFU per ml. The results of a drug sensitivity test indicated that these species were sensitive to 11 antibiotics. This is the first report of A. dhakensis, A. hydrophila and A. jandaei being isolated from a mixed infection in Siamese crocodiles. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we isolated three species of Aeromonas (A. dhakensis, A. hydrophila and A. jandae) from farmed Siamese crocodiles with fatal fibrinous pneumonia and septicaemia. This is the first description of a mixed infection with three Aeromonas species among captive crocodilians.

[Preliminary study of auditory cortex resting-state fMRI features for adult post-lingual deafness]

Objective: To understand the auditory cortex resting-state fMRI features for adult post-lingual deafness.Method: The author performed functional connectivity analysis on the study subjects with resting-state fMRI,the region of interest(ROI) of which were based separately on the left and right sides of primary auditory cortex. The data were collected from 8 cases with severe or above sensorineurally post-lingual deafness,compared to a control group of 8 cases with normal hearing. Result: When ROI were based on the left A1 areas of all subjects, the main activating area in the control group was bilateral superior temporal gyrus(STG), while the post-lingual deafness group included the bilateral STG, pre-central gyri, left Transverse temporal gyrus(TTG), post-central gyri and right TTG (P<0.01); when ROI were based on the right A1 areas of all subjects, the main activating area in the control group was the bilateral STG, while the post-lingual deafness group included the bilateral STG, right precentral gyri and post-central gyr i(P<0.01). The data showed statistical significance(P<0.05). Conclusion: After hearing loss functional reorganization takes place in the brains of adults with post-lingual deafness, resulting in possible enhancement of visual sense, tactile sense and other sensory systems in order to compensate information acquisition in daily life. .

[Gastroesophageal reflux disease is associated with high risk of obstructive sleep apnea syndrome]

Objective: To investigate the relationship between gastroesophageal reflux disease (GERD) and obstructive sleep apnea syndrome(OSAS). Methods: Patients diagnosed as GERD and healthy controls without GERD related symptoms or endoscopic esophagitis were enrolled from October 2017 and December 2017. All subjects completed Berlin Questionaire to assess the risk of OSAS. Univariate and multivariate logistic regression models were applied to identify risk factors of OSAS. Results: A total of 177 subjects (97 GERD, 80 controls) were finally selected. Significantly more patients in GERD group had high risk OSAS than those in controls [36.1%(35/97) vs. 17.5%(14/80), P=0.005]. In GERD group, patients with erosive reflux diseases (ERD) had especially higher proportion of high risk OSAS compared with the non-ERD group and the healthy controls [53.3% (24/45) vs. 20.8% (10/48) and 17.5% (14/80), P=0.001]. On univariate analysis, male, aging and reflux esophagitis were identified as risk factors of OSAS (all P<0.01). On multivariate analysis, male (OR=12.156, 95%CI 1.382-106.905, P=0.024), aging (OR=1.132, 95%CI 1.051-1.220, P=0.001), acid regurgitation with reflux esophagitis (OR=5.157, 95%CI 1.327-20.034, P=0.018) were significant risk factors. Conclusions: More GERD patients are combined with high risk OSAS than controls, especially subjects with reflux esophagitis. Male and aging GERD patients with acid regurgitation and reflux esophagitis need further evaluation on OSAS screening.

[Analysis of the impact of job characteristics and organizational support for workplace violence]

Objective: To analyze the effect of job characteristics and organizational support for workplace violence, explore the influence path and the theoretical model, and provide a theoretical basis for reducing workplace violence. Methods: Stratified random sampling was used to select 813 medical staff, conductors and bus drivers in Chongqing with a self-made questionnaire to investigate job characteristics, organization attitude toward workplace violence, workplace violence, fear of violence, workplace violence, etc from February to October, 2014. Amos 21.0 was used to analyze the path and to establish a theoretical model of workplace violence. Results: The odds ratio of work characteristics and organizational attitude to workplace violence were 6.033 and 0.669, respectively, and the path coefficients were 0.41 and-0.14, respectively (P<0.05). The Fitting indexes of the model: Chi-square (χ(2)) =67.835, The ratio of the chi-square to the degree of freedom (χ(2)/df) =5.112, Good-of-fit index (GFI) =0.970, Adjusted good-of-fit index (AGFI) =0.945, Normed fit index (NFI) =0.923, Root mean square error of approximation (RMSEA) =0.071, Fit criterion (Fmin) =0.092, so the model fit well with the data. Conclusion: The job characteristic is a risk factor for workplace violence while organizational attitude is a protective factor for workplace violence, so changing the job characteristics and improving the enthusiasm of the organization to deal with workplace violence are conducive to reduce workplace violence and increase loyalty to the unit.

Drug Resistance and Gene Transfer Mechanisms in Respiratory/Oral Bacteria

Growing evidence suggests the existence of new antibiotic resistance mechanisms. Recent studies have revealed that quorum-quenching enzymes, such as MacQ, are involved in both antibiotic resistance and cell-cell communication. Furthermore, some small bacterial regulatory RNAs, classified into RNA attenuators and small RNAs, modulate the expression of resistance genes. For example, small RNA sprX, can shape bacterial resistance to glycopeptide antibiotics via specific downregulation of protein SpoVG. Moreover, some bacterial lipocalins capture antibiotics in the extracellular space, contributing to severe multidrug resistance. But this defense mechanism may be influenced by Agr-regulated toxins and liposoluble vitamins. Outer membrane porin proteins and efflux pumps can influence intracellular concentrations of antibiotics. Alterations in target enzymes or antibiotics prevent binding to targets, which act to confer high levels of resistance in respiratory/oral bacteria. As described recently, horizontal gene transfer, including conjugation, transduction and transformation, is common in respiratory/oral microflora. Many conjugative transposons and plasmids discovered to date encode antibiotic resistance proteins and can be transferred from donor bacteria to transient recipient bacteria. New classes of mobile genetic elements are also being identified. For example, nucleic acids that circulate in the bloodstream (circulating nucleic acids) can integrate into the host cell genome by up-regulation of DNA damage and repair pathways. With multidrug resistant bacteria on the rise, new drugs have been developed to combate bacterial antibiotic resistance, such as innate defense regulators, reactive oxygen species and microbial volatile compounds. This review summaries various aspects and mechanisms of antibiotic resistance in the respiratory/oral microbiota. A better understanding of these mechanisms will facilitate minimization of the emergence of antibiotic resistance.

[Application of endoscope assisted curved laryngoscope in laryngeal microsurgery of patients with difficulty laryngeal exposure]

Objective:To investigate the feasibility and clinical value of endoscope assisted curved laryngoscopy in laryngeal microsurgery of patients with difficulty laryngeal exposure. Method:The data of 28 patients with difficulty laryngeal exposure underwent microlaryngosurgery with endoscope assisted curved laryngoscopy technique were collected. Result:Surgeries with endoscope assisted curved laryngoscopy technique were completed successfully one-time in all patients. The fully exposure of glottis was 100%. All cases were followed up for 2 to 18 months. No residual disease or recurrence occurred and no obvious complication occurred. Conclusion:Endoscope assisted curved laryngoscopy technique is a useful solution to difficulty laryngeal exposure. It has satisfactory glottis exposure, clear surgical field and fewer complications which is worthy of promotion.

[The effects and related mechanism of salvianolate on rats with myocardial ischemia-reperfusion injury]

Objective: To investigate the effect and related mechanism of salvianolate on myocardial ischemia-reperfusion (I/R) injury in rats. Methods: Thirty-six adult Sprague-Dawley rats were divided into three groups (n=12 each) using random number table method: control group (coronary artery was not ligated) , I/R group (myocardial I/R model was established by ligation and opening of left anterior descending coronary artery) , and salvianolate+I/R group (5 mg/kg of salvianolate was injected through the tail vein at the time of reperfusion) .Triphenyltetrazolium chloride (TTC) stain was utilized to measure the myocardial infarct size. The ELISA method was used to detect myocardial necrotic markers, including cardiac troponin T (TnT) , creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) . Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to analyses the levels of apoptosis. The levels of cleaved Caspase-3 protein were analyzed with Western blot.Cold luminescence method was used to detect the ATP level of myocardial tissue. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in myocardial tissue were detected by immunofluorescence. Results: (1) The infarct size in control group, I/R group and salvianolate+I/R group were 0, (23.90±5.66) %, and (12.06±5.97) %, respectively (P<0.01 or 0.05) . (2) The TnT level was (0.04±0.03) , (16.96±2.80) , and (6.95±2.31) ng/ml, the CK-MB level was (43.6±23.5) , (1 135.8±180.6) ,and (390.3±121.5) U/L, the LDH level was (119.0±58.6) , (1 838.6±543.8) , and (631.6±228.3) U/L in control group, I/R group and salvianolate+I/R group, all significantly lower in salvianolate+I/R group than in I/R group (all P<0.01) . (3) The rate of TUNEL positive myocardial cells were (1.07±1.16) %, (21.36±4.11) %,and (13.30±3.67) % in control group, I/R group,and salvianolate+I/R group (all P<0.01) . (4) The cleaved Caspase-3 expression was 0.11±0.05, 0.84±0.20,and 0.43±0.09 in control group, I/R group, and salvianolate+I/R group (all P<0.01) . (5) The ATP level of myocardial tissue was (100.0±0.0) %, (34.2±9.2) %,and (62.1±18.0) % respectively in control group, I/R group, and salvianolate+I/R group (all P<0.01) . (6) There was almost no 8-OHdG expression in the myocardial tissue of control group. The expression of 8-OHdG in the myocardial tissue of I/R group was greater than that of the control group. The expression of 8-OHdG in the myocardial tissue of salvianolate+I/R group was less than that of the I/R group. Conclusion: Salvianolate may alleviate myocardial I/R injury of rat through reducing the mitochondrial DNA oxidative damage, protecting mitochondrial function and inhibiting the apoptosis of myocardial cells.

[Application of endoscope assisted curved laryngoscopy technique in transoral laryngopharyngeal minimally invasive surgery]

Objective: To explore the possibility of endoscope assisted curved laryngoscopy technique applied in transoral laryngopharyngeal minimally invasive surgery and evaluate the advantages of this technique. Methods: Eight patients with huge benign lesions in larynx and pharynx undergoing transoral microsurgery at Peking University Third Hospital between February 2016 and February 2017 were enrolled in this study.The diagnosis included cyst at the base of tongue in two patients, cysts in the epiglottis in two patients, hemangioma in two patients, multiple masses of the hypopharynx and amyloidosis in supraglottic area in one patient each.The time and exposure during surgery, occurrence rate of complication and conditions of following-up were recorded. Results: The mean time of surgery was 20 min, the exposure was satisfying.There was no obvious complication after surgery.No residual or recurrent lesion was observed after 1 to 12 months follow-up(mean time 4.5 months). Conclusion: The endoscope assisted curved laryngoscopy technique has advantages in shortening the time of surgery, improving exposure and reducing the rate of complication and recurrence.

Characterization and transplantation of enteric neural crest cells from human induced pluripotent stem cells

The enteric nervous system (ENS) is recognized as a second brain because of its complexity and its largely autonomic control of bowel function. Recent progress in studying the interactions between the ENS and the central nervous system (CNS) has implicated alterations of the gut/brain axis as a possible mechanism in the pathophysiology of autism spectrum disorders (ASDs), Parkinson's disease (PD) and other human CNS disorders, whereas the underlying mechanisms are largely unknown because of the lack of good model systems. Human induced pluripotent stem cells (hiPSCs) have the ability to proliferate indefinitely and differentiate into cells of all three germ layers, thus making iPSCs an ideal source of cells for disease modelling and cell therapy. Here, hiPSCs were induced to differentiate into neural crest stem cells (NCSCs) efficiently. When co-cultured with smooth muscle layers of ganglionic gut tissue, the NCSCs differentiated into different subtypes of mature enteric-like neurons expressing nitric oxide synthase (nNOS), vasoactive intestinal polypeptide (VIP), choline acetyltransferase (ChAT) or calretinin with typical electrophysiological characteristics of functional neurons. Furthermore, when they were transplanted into aneural or aganglionic chick, mouse or human gut tissues in ovo, in vitro or in vivo, hiPSC-derived NCSCs showed extensive migration and neural differentiation capacity, generating neurons and glial cells that expressed phenotypic markers characteristic of the enteric nervous system. Our results indicate that enteric NCSCs derived from hiPSCs supply a powerful tool for studying the pathogenesis of gastrointestinal disorders and brain/gut dysfunction and represent a potentially ideal cell source for enteric neural transplantation treatments.

[Characterization and uncertainty evaluation of aqueous reference materials for cholesterol]

Objective: Characterization and evaluation of the uncertainty of the reference materials of cholesterol in aqueous solution. Methods: The certified reference material GBW09203b was weighed accurately and dissolved into methyl cyclodextrin aqueous solution to prepare six kinds of candidate reference materials of cholesterol according to the concentration. The materials were tested for homogeneity and stability using routine methods and were evaluated the uncertainty derived from the inhomogeneity and instability. The uncertainty due to measurement was derived from the purity of the raw material, the weighing and the density measurement. The certified values and expanded uncertainties were calculated according to the ISO Guide. The expanded uncertainty of the certified value was the combination of standard uncertainty of measurement, inhomogeneity and instability. The coverage factor, k, was determined from the Student's t-distribution corresponding to the calculated effective degrees of freedom and 95% level of confidence. Results: It showed that the six candidate reference materials were homogeneous and were tested to be stable for at least 1 year at -70 ℃ and -20 ℃ using the isochronous stability study. The relative uncertainties due to the inhomogeneity were 0.14%, 0.11%, 0.13%, 0.47%, 0.39% and 0.11%. The relative uncertainty due to the instability was 0.25% at -70 ℃. The uncertainties of measurement were 0.06%, 0.05%, 0.05%, 0.05%, 0.05% and 0.05%.The certified values (reference value ± expanded uncertainty, mmol/L) were as follows: (0.651±0.004), (1.310 ±0.007), (2.574±0.015), (5.210±0.055), (7.710±0.072), (10.242±0.056) mmol/L. Conclusions: Six kinds of certified reference materials for cholesterol in aqueous solution have been prepared, which were homogeneity, stable and reliable. It showed that the uncertainty of measurement was very small compared with the uncertainty due to inhomogeneity and instability.

[Prevalence and control status of diabetes in elderly community residents and risk factors]

Objective: To analyze the prevalence and control status of diabetes in elderly community residents and related risk factors. Methods: A population-based cross-sectional study was conducted in elderly community residents aged 60-95 years in an urban district of Beijing from September 2009 to June 2010 to collect the general health status of the elderly in the community, the prevalence of diabetes, medication treatment, and laboratory tests were conducted. Results: A sample of 2 102, including 848 males and 1 254 females, were selected through randomized clustering sampling for this study. Most participants had higher educational levels, and the smoking and drinking rates were low among them. The prevalence of diabetes, impaired fasting glucose and impaired glucose tolerance were 24.8%, 2.5% and 30.6%, respectively. The awareness, treatment and control rates of diabetes were 78.5%, 69.3% and 15.9%, respectively. Multivariate logistic regression analysis showed that ORs of obesity, family diabetes history for diabetes were 1.42 (95%CI: 1.14-1.76) and 3.42 (95% CI: 2.70-4.35), respectively compared with control group. Also, obesity and family diabetes history were related risk factors for control status of diabetes. Conclusions: The prevalence of diabetes was relatively high, but the control rate was low in elderly community residents. Obesity, unhealthy lifestyles and family diabetes history were related risk factors.