Analysis of tuberculosis epidemiological characteristics and drug resistance among the floating population in Beijing in 2019 / 中华流行病学杂志

Objective: To analyze the epidemic characteristics and drug resistance of pulmonary tuberculosis among the floating population in Beijing and to provide a scientific basis for formulating strategies for the prevention and control of tuberculosis among the floating population. Methods: Data of tuberculosis patients who were positive for Mycobacterium tuberculosis culture was collected from 16 districts and one municipal institution of tuberculosis control and prevention in Beijing in 2019. The strain samples were tested for drug sensitivity by the proportional method. According to household registration location, patients were divided into the floating population and Beijing registration. SPSS 19.0 software analyzed tuberculosis patients' epidemic characteristics and drug resistance in the floating population. Results: In 2019, there were 1 171 culture-positive tuberculosis patients in Beijing, among the floating population, 593 (50.64%) patients were identified, with a male-to-female sex ratio of 2.2∶1 (409∶184). Compared to patients under household registration as Beijing residents, a higher proportion of young adults aged 20-39 years (65.09%,386/593) were noticed, with 55.65% (330/593) reported from the urban areas and 96.80% (574/593) were reported the first time. The differences were statistically significant (all P<0.05). After completing the drug sensitivity test, 37 cases were with multiple drug-resistant tuberculosis, accounting for 6.24% (37/593). The rates of isoniazid resistance (42.11%,8/19) and multidrug resistance (21.05%,4/19) in floating population patients after retreatment were significantly higher than those in newly treated patients (11.67%, 67/574 and 5.75%, 33/574), and the differences were statistically significant (all P<0.05). Conclusions: Most patients with tuberculosis in the floating population in Beijing in 2019 were young males aged 20-39 years. The reporting areas were urban areas and the newly treated patients mainly. The patients with tuberculosis in the re-treated floating population were more likely to suffer from multidrug and drug resistance, which should be taken as the key population for prevention and control.

Effects of Porphyromonas gingivalis injected through tail vein on the expressions of biomarkers in neural stem cells and neurons of wild-type rats hippocampus / 中华口腔医学杂志

Objectives: To study the effects of Porphyromonas gingivalis (Pg) injected through tail vein on the molecular expression levels of biomarkers of neural stem cells (NSC) and neurons in the hippocampus of wild-type adult rats, and the effects on hippocampal neurogenesis. Methods: Eighteen male Sprague-Dawley (SD) rats were randomly divided into 3 groups based on the table of random numbers (n=6 in each group). In low-intensity group and high-intensity group, rats were injected intravenously through tail vein with 200 μl Pg ATCC33277 [1.0×103 and 1.0×108 colony forming unit (CFU), respectively] 3 times per week for 8 weeks. In the sham group, 200 μl of phosphate buffer saline (PBS) was given instead. Behavioral tests: the navigation and the exploration tests using Morris water maze (MWM) were applied to evaluate learning and memory ability of rats. Immunohistochemistry was performed to detect cells positively expressing nestin, doublecortin (DCX) and neuronal nuclei (NeuN) in the subgranular zone (SGZ) of rats in each group. Western blotting was used to evaluate the expression levels of nestin, DCX and NeuN in rat hippocampus. Results: Learning and memory abilities: on day 5 of navigation test, the lagency time was 22.83 (16.00, 38.34) s in the high-intensity group, significantly longer than the sham group [5.59 (5.41, 6.17) s] (t=-11.17, P<0.001). There were no significant differences between the low-intensity group [9.85 (8.75, 21.01) s] and the sham group (t=-6.83, P=0.080). Results in the exploration test showed that, in the high-intensity group, the number of fime crossing over the previous platform area within 60 s was 1.50 (1.00, 2.00), significantly less than the sham group [4.00 (2.75, 4.00)] (t=9.75, P=0.003); no significant differences between the low-intensity group [2.50 (2.00, 3.00)] and the sham one (t=4.50, P=0.382). Immunohistochemistry showed that the nestin+ cell density in the low-intensity group [(35.36±4.32) cell/mm2] and high-intensity group [(26.51±5.89) cell/mm2] were significantly lower than the sham group [(59.58±14.15) cell/mm2] (t=24.21, P=0.018; t=33.07, P=0.005); as for the mean absorbance of DCX+ cells, the low-intensity group (0.007±0.002) and the high-intensity group (0.006±0.002) were significantly lower than the sham group (0.011±0.001) (t=0.004, P=0.018; t=0.006, P=0.005); compared with the sham group [(1.13±0.14)×103 cell/mm2], the density of NeuN+ neurons in the high-intensity group [(0.75±0.08)×103 cell/mm2] was significantly reduced (t=0.38, P=0.017), and was not significantly changed in the low-intensity group [(0.88±0.19)×103 cell/mm2] (t=0.25, P=0.075). Western blotting results showed that, compared with the sham group, the expression levels of nestin, DCX, and NeuN were significantly reduced in the high-intensity group (t=0.74, P<0.001; t=0.18, P=0.014; t=0.35, P=0.008), but were not statistically changed in the low-intensity group (t=0.18, P=0.108; t=0.08, P=0.172; t=0.19, P=0.077). Conclusions: Pg injected through tail vein may reduce learning and memory abilities of wild-type rats, and may reduce the number of nestin, DCX, and NeuN-positive cells, and the protein expression levels of the above molecules in the hippocampus.

Expression of long non-coding RNA MALAT1, NEAT1 and NEAT2 in peripheral blood of tuberculosis patients / 中华疾病控制杂志

Objective To analyze the differences in the expression levels of the lncRNA MALAT1, NEAT, NEAT2 in peripheral blood mononuclear cell (PBMC) from tuberculosis patients and healthy controls. Methods We detected the lncRNA expression levels in PBMC from 79 tuberculosis patients and 82 healthy controls by quantitative reverse transcription polymerase chain reaction, and analyzed the correlation between lncRNA expression levels and some clinical features and laboratory indicators in tuberculosis patients. Results The expression levels of MALAT1, NEAT1 in PBMC of tuberculosis patients were significantly higher than healthy controls (Z=-4.386, P<0.001; Z=-10.175, P<0.001). There was no significant difference in the expression of NEAT2 between tuberculosis patients and healthy controls (Z=-0.203，P=0.839). The correlation results of lncRNA levels and some clinical features, laboratory indicators in tuberculosis patients suggested that the NEAT2 level in PBMC of newly treated tuberculosis patients was higher than recurrent tuberculosis patients, while the NEAT2 level in PBMC of sputum smear positive tuberculosis patients was lower than that of sputum smear negative tuberculosis patients (all P<0.05). There was a negative correlation between MALAT1 level and erythrocyte sedimentation rate (rs=-0.256, P=0.034). Conclusion MALAT1 and NEAT1 are abnormally expressed in PBMC of tuberculosis patients, and may be involved in the pathogenesis of pulmonary tuberculosis.

Association of red blood cell damage with arachidonic acid / 中国骨伤

<p><b>OBJECTIVE</b>To study the correlation between arachidonic acid (AA) and acute red blood cells damage in rats, and to build a model with hidden blood loss in vivo, and to explore the pathological mechenism of hidden blood loss.</p><p><b>METHODS</b>A total of 50 male adult Sprague-Dawley rats weighing (200 ± 20) g were randomly divided into five groups (n = 10): control group and four experimental groups. The rats in the experimental groups were given 0.5 ml different concentrations of AA dilu- ents, 5, 10, 20, 40 mmol/L respectively. The blood samples were collected from orbital venous at the beginning and 24, 48, 72 hours after administration. Then the changes of hemoglobin (Hb) ,red blood cell count (RBC), glutathione peroxidase (GSH- PX) activity, total superoxide dismutase (T-SOD) activity and hydrogen peroxide (H202) in the blood samples were tested.</p><p><b>RESULTS</b>Significant hidden blood loss occurred when the concentration was 10 mmol/L in the experimental group, with the RBC and Hb sharply reduced in blood samples. The Hb and RBC were reduced in all the experimental groups and control group at 24 hours after administration, while in the experimental groups they changed more obviously. The GSH-PX activity, T-SOD activity and H₂O₂were also significantly reduced in all groups, and the changes showed significant differences. The Hb and RBC were relatively stable in the control group and the experimental groups at 48 hours after administration; while GSH-PX activity, T-SOD activity and H₂O₂were all significantly decreased, and the changes in the experimental groups were more notable.</p><p><b>CONCLUSION</b>Elevated levels of AA in the blood causes oxidative stress in the red blood cells, leading to the damage of red blood cells and hemoglobin, which is responsible for hidden blood loss.</p>