Objective To examine the gene expression levels of matrix metalloproteinase-1(MMP-1), tissue inhibitor of metalloproteinase-1 ( TIMP-1) in peripheral blood mononuclear cells (PBMC) and sera in the patients with chronic hepatitis B (CHB) and to investigate the value of message RNA(mRNA) expression of MMP-1 and TIMP-1 for diagnosing liver fibrosis. Methods PBMC and sera samples were collected from 37 CHB patients and 20 healthy controls. The total RNA isolated from PBMC was reversely transcribed into cDNA. The mRNA levels of MMP-1 and TIMP-1 in PBMC were examined by real-time fluorescence quantitative reverse transcription polymerase chain reaction (FQ-RT-PCR). The serum levels of MMP-1 and TIMP-1 were determined by sandwich enzyme-linked immunosorbent assay (ELISA). Liver tissues were obtained from all these patients by biopsy and subsequently used for evaluating liver fibrosis stages (S). Intergroup comparison was performed by non parametric test. The correlation analysis was performed by Spearman. Results The MMP-1 and TIMP-1 mRNA levels in PBMC from healthy controls were low. The MMP-1 mRNA levels in PBMC from CHB patients were not significantly different from those in healthy controls,while the TIMP-1 mRNA levels were remarkably higher in CHB patients' PBMC compared to healthy controls. Both the MMP-1 mRNA levels in PBMC and the MMP-1 protein levels in sera were not significantly different among CHB patients at different disease stages and healthy controls (χ~2 =8. 960,P=0.111l ;χ~2 =7. 898, P = 0.211). However, the TIMP-1 mRNA levels in PBMC and the TIMP-1 protein levels in sera increased gradually along with the disease progressed from S1 to S4. The TIMP-1 mRNA levels in PBMC were (1.67±0. 84) lg copy/μL, (3. 48±2. 08) lg copy/μL,(5. 86±3. 47) lgcopy/μL and (8. 14 ± 6. 48) lg copy/μL from stage 1 to 4 respectively, while the protein levels of TIMP-1 in sera were (233. 73±64. 84) ,μg/L, (262. 10±71. 12) μg/L, (301. 15±62. 74)μg/L and(381. 15 ± 152. 75)μg/L, respectively. The differences between each stages were statistically significant (χ~2'= 14. 290, P=0.002,χ~2 = 12.209, P=0. 007). The TIMP-1 mRNA levels in PBMC and the TIMP-1 serum levels were positively correlated with liver fibrosis stage (r=0. 752, P<0. 01;r=0. 530, P=0. 008). Conclusions The TIMP-1 mRNA level in PBMC and TIMP-1 protein level in serum are closely related with liver fibrosis stages. These two parameters, especially the TIMP-1 mRNA level in PBMC, can be potentially new markers for diagnosing liver fibrosis.

Objective To study the clinical characteristics, diagnostic methods and therapeutic efficacy of pneumocystis pneumonia (PCP) in patients with acquired immunodeficiency syndrome (AIDS). Methods Sixty-nine AIDS cases of PCP were diagnosed according to the criteria of USA Centers for Disease Control and Prevention revised in 1993. The clinical symptoms and signs of the patients were observed. The peripheral blood lymphocyte counts, blood gas analysis and bronchoalveolar lavage fluid (BALF) were checked and transbronchoscopic lung biopsy was performed. Results All studied patients were in the late stage of AIDS. The main clinical manifestations included fever (100.0%), cough (97.1%), and dyspnea (92.80%). Pulmonary rales could be heard in 42 cases (60.9% ). Peripheral CD4+ T lymphocyte counts ranged from 1 × 106 -88 × 106/L. Fifty-two cases (75.4% ) had low arterial partial pressure of oxygen value of less than 10.7 kPa (1 kPa = 7.5 mm Hg). Sixty-one cases (88.4 %) had elevated serum lactate dehydrogenase (LDH) level. Bilateral diffused interstitial change (46.4%) and ground-glass shadow (29.0%) were the most common abnormal chest radiological findings. Pneumocystis organisms were detected in the BALF from 2 patients and in the transbronchial biopsy (TBB) tissue from 35 patients. All patients were treated with compound sulfamethoxazole. Thirty-three were treated with corticosteroid simultaneously and 27 were assisted with mechanical ventilation. Fifty patients recovered or got improved, eleven died, and eight left hospital because of deteriorated condition. Conclusions When an AIDS patient represents with fever, cough, dyspnea, hypoxemia, elevated serum I.DH level, CD4+ T lymphocyte count below 100 × 106/L, and interstitial pneumonia or ground-glass shadow in chest images, the diagnosis of PCP could be made presumptively. It is difficult to make a nosogenic diagnosis of PCP, but TBB considerably increases the positive rate of pneumocystis. Compound sulfamethoxazole is recommended as the first selected drug. In severe cases, corticosteroid and assisted mechanical ventilation combined with compound sulfamethoxazole could remarkably improve the prognosis of PCP.

Objective To investigate the histopathological characteristics of colonoscopic biopsy specimens from AIDS patients .Methods A total of 310 clinically confirmed AIDS patients with abdominal pain, diarrhea or tenesmus were enrolled from Guangzhou NO .8 People’s Hospital during 2010 and 2014. All patients underwent colonoscopic examination , and the biopsy specimens were collected .Conventional HE staining, special stainings including Gomori’s methenamine silver ( GMS), Periodic Acid-Schiff stain (PAS), acid-fast staining, and immunohistochemical staining of cytomegalovirus (CMV) were performed. Results The biopsy specimens showed mucosa chronic inflammation (93.9%), epithelial degeneration and necrosis;the local erosion and ulcer formation were observed in severe cases .Among 310 patients, the infective pathogens were identified in 139 ( 44.8%) cases, including 47 ( 15.2%) cases with CMV infections, 36(11.6%) cases with mycobacterium infections , 21(6.8%) cases with penicillium marneffei infections, 10(3.2%) cases with Cryptococcus infections, 3(1.0%) cases with candida infections, 2(0.6%) cases with cryptozoite infections and the rest 20(6.5%) cases were with uncertain pathogens . Conclusion Chronic inflammatory lesions are common in patients with AIDS , and colonoscopic mucosal biopsy can help to identify the pathogens of intestinal opportunistic infection .

This article introduces ethical problems emerging in the imaging trials in clinical practice,and stresses the importance of protecting the privacy of volunteers and patients,and their legal rights of informed consent.This article also stresses the importance of the respect for the basic human right of volunteers and patients,and puts forward some countermeasures to promote the efficiency and reasonable supervision system in the clinical trials.Last but not least,it also emphasizes the significance of a personalized-style of care for volunteers and patients.

Objective:To explore the changes of the auditory event-related potentials P300 and the Montreal Cognitive Assessment (MoCA) in the chronic mild lead poisoning in order to find out the impairment of cognitive function and intervene early.Methods:In February 2020, 50 patients with chronic mild lead poisoning in Wuhan Center for Prevention and Treatment of Occupational Diseases from June 2011 to June 2015 were selected as the case group, and 50 healthy people were selected as the control group. The changes of auditory event-related potential P300 and MOCA of the two groups were analyzed.Results:Compared with the control group, the latency of P300 of auditory event-related potential in the case group was prolonged and the amplitude was decreased ( P<0.05) . Compared with the control group, the total score of MoCA in the case group was decreased, the mean score of language, abstract and delayed memory items decreased, and the differences were statistically significant ( P<0.05) . Conclusion:The combination of auditory event-related potential P300 and MOCA is helpful to detect the early cognitive impairment in chronic lead poisoning population, and auditory event-related potential P300 is an objective and effective early detection method.

Objective:To explore the changes of the auditory event-related potentials P300 and the Montreal Cognitive Assessment (MoCA) in the chronic mild lead poisoning in order to find out the impairment of cognitive function and intervene early.Methods:In February 2020, 50 patients with chronic mild lead poisoning in Wuhan Center for Prevention and Treatment of Occupational Diseases from June 2011 to June 2015 were selected as the case group, and 50 healthy people were selected as the control group. The changes of auditory event-related potential P300 and MOCA of the two groups were analyzed.Results:Compared with the control group, the latency of P300 of auditory event-related potential in the case group was prolonged and the amplitude was decreased ( P<0.05) . Compared with the control group, the total score of MoCA in the case group was decreased, the mean score of language, abstract and delayed memory items decreased, and the differences were statistically significant ( P<0.05) . Conclusion:The combination of auditory event-related potential P300 and MOCA is helpful to detect the early cognitive impairment in chronic lead poisoning population, and auditory event-related potential P300 is an objective and effective early detection method.

Objective To investigate the liver histological characteristics of children with chronic hepatitis B (CHB).Methods We recruited data of children with CHB and liver biopsy,then analyzed their liver histopathological characteristics and their associations with laboratory parameters.Results One hundred and twenty-four children with CHB were included in the present study,including 114 (91.9％) HBeAg-positive CHB children and 10 (8.1％) HBeAg-negative CHB children.In HBeAg-positive CHB children,the frequency of significant necroinflammation stratified by ALT levels was 32.1％ (9/28) in ALT ≤ULN,60.7％ (17/28) in ALT(1-2) ×ULN and 81.0％ (47/58) in ALT＞2 ×ULN group,while significant fibrosis was 46.4％ (13/28) in ALT ≤ ULN,71.4％ (20/28) in ALT (1-2) × ULN and 74.1％ (43/58) in ALT ＞ 2 × ULN group,respectively.Significant liver histological abnormalities were much higher in the ALT ＞ 2 × ULN and ALT (1-2) × ULN groups than the ALT ≤ ULN group.Logistic analysis indicated only AST levels associated with significant inflammation (OR =1.032,P =0.008) and significant fibrosis (OR =1.026,P =0.007).Conclusion Frequencies of significant liver histological abnormalities in children with CHB are high,and AST levels are associated with them.

Abstract The COVID-19 pandemic has posed a series of complex challenges. COVID-19 in children and adolescents is generally less severe than in adults and the elderly; however, some children and adolescents may experience severe complications and adverse health effects even after mild or asymptomatic COVID-19 infections. The article focuses on gathering the epidemic characteristics, health impact, risk factors, prevention and control measures, and vaccination status of children and adolescents with COVID-19 infection to provide recommendations for protecting children and adolescents in the post COVID-19 era.

Curriculum integration has become the core content of the current medical education reform.With the rapid development of information technology,how to reflect the teaching and learning effects and to further improve them,is one of the difficulties in the reform of the integrated curriculum.In view of the problems of single form of assessment model,separate classroom teaching and extracurricular teaching evaluation,low utilization of network and electronic teaching resources,we make full use of network methods to carry out reform on the current formative teaching evaluation system.With the purpose of formative assessment and evaluation,the "Blackboard network teaching system" of the curriculum has been built,and the evaluation indexes of classroom teaching and extracurricular teaching have been established.And at the same time,the formative assessment index has been enriched and perfected in a diversified form,and the formative assessment model adapted to the integrated curriculum is preliminarily explored.

Reducing lactate accumulation has always been a goal of the mammalian cell biotechnology industry. When animal cells are cultured in vitro, the accumulation of lactate is mainly the combined result of two metabolic pathways. On one hand, glucose generates lactate under the function of lactate dehydrogenase A (LDHA); on the other hand, lactate can be oxidized to pyruvate by LDHB or LDHC and re-enter the TCA cycle. This study comprehensively evaluated the effects of LDH manipulation on the growth, metabolism and human adenovirus (HAdV) production of human embryonic kidney 293 (HEK-293) cells, providing a theoretical basis for engineering the lactate metabolism in mammalian cells. By knocking out ldha gene and overexpression of ldhb and ldhc genes, the metabolic efficiency of HEK-293 cells was effectively improved, and HAdV production was significantly increased. Compared with the control cell, LDH manipulation promoted cell growth, reduced the accumulation of lactate and ammonia, significantly enhanced the efficiency of substrate and energy metabolism of cells, and significantly increased the HAdV production capacity of HEK-293 cells. Among these LDH manipulation measures, ldhc gene overexpression performed the best, with the maximum cell density increased by about 38.7%. The yield of lactate to glucose and ammonia to glutamine decreased by 33.8% and 63.3%, respectively; and HAdV titer increased by at least 16 times. In addition, the ATP production rate, ATP/O₂ ratio, ATP/ADP ratio and NADH content of the modified cell lines were increased to varying degrees, and the energy metabolic efficiency was significantly improved.
Animals ; Humans ; L-Lactate Dehydrogenase/genetics* ; Lactic Acid ; Adenoviruses, Human ; Ammonia ; HEK293 Cells ; Glucose/metabolism* ; Adenosine Triphosphate/metabolism* ; Kidney/metabolism* ; Mammals/metabolism*