Objective To provide reliable indicators for effective prevention and control of COVID-19, we examined the biochemical indicators as well as anti-SARS-CoV-2 IgM and IgG antibodies in confirmed and suspected COVID-19 patients. Methods A total of 56 confirmed and suspected COVID-19 cases quarantined during January-March, 2020 in Gansu Provincial People′s Hospital and People′s Hospital of Xigu District, Gansu Province were included.Based on the results of nucleic acid testing and CT scan finding, they were divided into three groups: positive in both nucleic acid testing and CT scan finding; positive in nucleic acid testing but negative in CT scan finding; negative in both nucleic acid testing and CT scan finding.COVID-19 viral nucleic acid was detected and chest CT scan was performed.The following biochemical indicators were examined: total protein, albumin, total bilirubin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, γ-glutamyltranspeptidase, creatine kinase and lactate dehydrogenase.SPSS 22.0 statistical software was used to analyze the differences in the biochemical indicators among these three groups, as well as the temporal trend of IgM and IgG antibodies at different points of time. Results There were significant differences in the mean values of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase between these three groups (P < 0.05), whereas no significant difference in the mean value of total protein and albumin (P>0.05).ROC curve indicated that aspartate aminotransferase had the largest maximum area under the curve (AUC, 0.834), whereas alanine aminotransferase had the highest sensitivity (1.0) and total bilirubin had the highest specificity (0.927).Thus, aspartate transaminase provided the best prediction for the diagnosis of COVID-19, with sensitivity of 0.786, specificity of 0.854, and the maximum AUC of 0.834.In 12 of 16 confirmed COVID-19 patients tested IgG positive after 10 days of diagnosis, and 10 of 10 confirmed COVID-19 patients tested IgG positive after 14 days of diagnosis. Conclusion Aspartate aminotransferase may be the most useful indicator in the diagnosis of COVID-19.

Large epiglottic cysts can block the glottis, leading to serious consequences. This condition presents a challenge in terms of airway management for anesthesiologists during induction of anesthesia. We report the use of a Shikani™ Seeing Optical Stylet combined with a Macintosh laryngoscope to aid tracheal intubation in seven patients with large epiglottic cysts. Use of this technique can avoid cyst rupture and allow smooth, safe intubation.
Epiglottis ; pathology ; Female ; Fiber Optic Technology ; methods ; Humans ; Intubation, Intratracheal ; methods ; Laryngeal Diseases ; pathology ; Laryngoscopes ; Male ; Middle Aged

Objective To observe the maximal heart rate changes, atrioventricular (A-V) conduction block and atrial fibrillation (AF) inducibility in dogs with vagosympathetic trunk exposed to electromagnetic fields (EMFs). Methods The vagosympathetic trunk of adult dogs was separatedand exposed to EMFs 0.043 kHz(2.87 μG, n=5) and to EMFs 2 kHz(0.34 μG, n=6) for two to three hours. Simultaneously, the vagosympathetic trunk was stimulated with 20 Hz frequency and 1-8 V intensity for 0.1 ms. Heart rate, presence of A-V conduction block and AF inducibility were determined. Results After 5-minutes exposure to EMFs 0.043 kHz (2.87 μG), the maximal heart rate decreased 29%, the voltage applied to vagosympathetic trunk required to induce A-V conduction block decreased by 60% in experimental group versus 5% increase in control group. This effect lasted 2 to 3 hours.While vagosympathetic trunk exposure to EMFs 2 kHz (0.34 μG) was associated with significant increase in the incidence of atrial premature beats, atrial tachycardia and AF, these effects could be blocked by propranolol and atropine. Conclusions Our results showed that 0.043 kHz (2.87 μG) EMFs exposure might reduce while 2 kHz(0.34 μG) EMFs exposure might increase AF inducibility. Our study thus suggested autonomic nervous system of dogs could be affected by EMFs exposure and 0.043 kHz (2.87 μG) EMFs exposure might be a novel option for AF prevention.

AIMTo investigate the molecular mechanism of protective effect of acidic oligose 971 on Alzheimer's disease mouse model by using microarray.

METHODSBalb/c mice were randomly divided into control group, beta-AP(25-35) i.c.v. injected group and 971-treated group. The learning-memory ability of mice was tested by Morris water maze experiment. Total RNA of the cerebral cortex was extracted from the mice of each group. cDNA microarrays containing 1176 genes were used to investigate the gene expression pattern of each group. Expressions of 5 genes were randomly selected for further confirmation by RT-PCR.

RESULTSIcv injection of beta-AP(25-35) caused significant impairments in spatial and working memory performances of mice in Morris water maze and which were relieved by the treatment of 971. Up- and down- regulated genes were 19 and 12 in beta-AP(25-35)-injected group vs control group, respectively. Up- and down- regulated genes were 13 and 4, respectively, in 971-treated group vs beta-AP(25-35)-injected group. RT-PCR results indicated that 5 genes showed identical results to that of the microarray.

CONCLUSIONThe protective effect of 971 on learning and memory ability of beta-AP(25-35)-treated mouse may be related to the expression changes of genes involved in cell cycle, DNA repair, nerve growth, synaptic plasticity and immune response, etc.

Alzheimer Disease ; chemically induced ; genetics ; physiopathology ; Amyloid beta-Peptides ; Animals ; Gene Expression Profiling ; Male ; Maze Learning ; drug effects ; Mice ; Mice, Inbred BALB C ; Neuroprotective Agents ; isolation & purification ; pharmacology ; Oligonucleotide Array Sequence Analysis ; Oligosaccharides ; isolation & purification ; pharmacology ; Peptide Fragments ; Phaeophyta ; chemistry ; Random Allocation

Objective To evaluate the risk of hepatitis B virus(HBV) infection among preschool children who were the non-responders to hepatitis B vaccine in future. Methods A prospective cohort study was conducted. Children aged 2 to 5 years were selected from 64 kindergartens.These children were inoculated three doses of hepatitis b vaccine at 0, 1 and 6 months after birth. Hepatitis B surface antigen (HBsAg)and Hepatitis B surface antibody (anti-HBs)were detected during the period from March to May 2015. The children who were HBsAg negative were enrolled in the study. The subjects were divided into exposure group (anti-HBs negative) and control group (anti-HBs positive) . The follow-up began on June 1, 2015 and ended on June 1, 2016. Serum HBsAg of children in the cohort was then collected and detected from June 1 to 30, 2016. At the end of the study, the HBsAg positive rates between two groups were compared. Results 83 children who received hepatitis B vaccine again during the follow-up period were excluded from 1 907 non-responders. The actual number in non-responders group was 1 824. 151 children were lost at the end of the study. The actual number of follow-up was 1 673 and 5 children were found to be positive for HBsAg and the infection rate was 0.30% (5/1673). In the respondent goup, 2 054 were enrolled and followed. Finally, 140 children were lost and none of the remaining 1 914 people were HBsAg positive at the end of the study. HBsAg positive rate was higher in the non-responder group than in the responder group (P=0.023). Conclusion There is a risk of HBV infection in the children who are non-responders to hepatitis B vaccine in future.

Objective To optimize the oxygen therapy regimens for infants with pulmonary diseases during bronchoscopy.Methods A prospective randomized,controlled,and single-center clinical trial was conducted on 42 infants who underwent electronic bronchoscopy from July 2019 to July 2021.These infants were divided into a nasal cannula(NC)group and a modified T-piece resuscitator(TPR)group using a random number table.The lowest intraoperative blood oxygen saturation was recorded as the primary outcome,and intraoperative heart rate and respiratory results were recorded as the secondary outcomes.Results Compared with the NC group,the modified TPR group had a significantly higher level of minimum oxygen saturation during surgery and a significantly lower incidence rate of hypoxemia(P<0.05).In the modified TPR group,there were 6 infants with mild hypoxemia,2 with moderate hypoxemia,and 1 with severe hypoxemia,while in the NC group,there were 3 infants with mild hypoxemia,5 with moderate hypoxemia,and 9 with severe hypoxemia(P<0.05).The modified TPR group had a significantly lower incidence rate of intraoperative respiratory rhythm abnormalities than the NC group(P<0.05),but there was no significant difference in the incidence rate of arrhythmias between the two groups(P>0.05).Conclusions Modified TPR can significantly reduce the risk of hypoxemia in infants with pulmonary diseases during electronic bronchoscopy,and TPR significantly decreases the severity of hypoxemia and the incidence of respiratory rhythm abnormalities compared with traditional NC.

OBJECTIVE: To observe the effect of Bruton's tyrosine kinase (BTK) on the proliferation and differentiation of osteoclasts and to explore the mechanism of BTK on bone destruction in periapical periodontitis. METHODS: After RAW264.7 cells induced with 100 ng·L⁻¹ receptor activator for nuclear factor-κB ligand (RANKL) for 5 days, osteoclast induction was confirmed by light microscopy, tartrate-resistant acid phosphatase (TRAP) staining, and quantitative real-time PCR (RT-qPCR). Then, BTK-small interfering RNA (BTK-siRNA) was transfected into cells induced for 5 days. After 24 h, the expression of TRAP mRNA was measured using RT-qPCR, and the proliferation and differentiation of osteoclasts were detected using CCK-8 and TRAP activity assay. Statistical analysis was performed. RESULTS: After RAW264.7 was induced with RANKL for 5 days, a large number of round, ellipse, irregularly protuberant, and TRAP-positive macrophages were observed under light microscopy. The expression of TRAP mRNA significantly reduced after 24 h of BTK-siRNA transfection (P<0.05). The detection of CCK-8 and TRAP activities showed that the proliferation and differentiation of osteoclasts significantly decreased (P<0.05). CONCLUSIONS Silencing of BTK can inhibit the proliferation and differentiation of osteoclasts. BTK can be used as a new target for the inhibition of osteoclasts.
Agammaglobulinaemia Tyrosine Kinase ; Cell Differentiation ; Cell Proliferation ; Macrophages ; Osteoclasts ; RANK Ligand

OBJECTIVETo establish a new mouse model of H-2 haploidentical stem cell transplantation from double donors (DHSCT) and compare with conventional haploidentical hematopoietic stem cell transplantation (HSCT) so as to alleviate transplant-related complications.

METHODSThe recipients CB6F1 of conventional HSCT group were pretreated by 8 Gy total body irradiation(TBI), and received 3×10donor (male C57) spleen mononuclear cells (spMNC) mobilized by G-CSF within 2 hours after TBI. Recipients CB6F1 of D-HSCT groups accepted 2 Gy TBI, and received total 12×10spMNC mobilized by G-CSF from 2 donors within 2 hours after TBI, each donor donated 6×10cells. According to the different strains and sex of donors, DHSCT were divided into 3 groups: in group A, the stem cells were from male C57 and female BALB/c; in group B, stem cells were from male C57 and male BALB/c, while the stem cells in group C were from male C57 and male C3H. Hematopoietic reconstruction, engraftment, GVHD and survival were observed among these 4 groups.

RESULTSThe nadir of white blood cell count after conventional HSCT were lower than 1×10/L and lasted for 3 to 5 days, while not less than 3×10/L after D-HSCT among either group A, B or C. The complete chimerism (CC) in conventional HSCT group was achieved quickly within only 1 week in peripheral blood. Mixed chimerism (MC) in peripheral blood was found within the first week after DHSCT among either group A, B or C, and transformed into stable CC within the second week eventually. Both GVHD morbidity and mortality of conventional HSCT were 100% at 34th day after transplantation.Among DHSCT groups,the overall GVHD morbidity and mortality at 34th day after transplant were 49.6% and 50%(P<0.01,P<0.05), respectively,and 60.4% and 81.2% at 50th day after transplant. Overall survival of 50 days was 50.9% that indicated a long survival in such mice DHSCT. The differences of hematopoietic reconstruction, donor cell engraftment, GVHD incidence, GVHD mortality and OS were not statistically significant among group A, B and C(P>0.05).

CONCLUSIONA new mouse model of H-2 haploidentical peripheral blood stem cell transplantation from double donors (DHSCT) has been successfully established by reducing conditioning intensity and increasing graft cell numbers from double haploidentical donors without GVHD prophylaxis. DHSCT successfully achieved stable complete chimerism, less GVHD morbidity and mortality and longer OS without hematopoietic suppression. This study provides experimental evidence for clinical application of HLA haploidentical peripheral blood stem cell transplantation from double donors.

OBJECTIVETo explore the biological characteristics of microvesicles(MV) derived from bone marrow mesenchymal stem cells (BM-MSC) and their capability supporting ex vivo expansion of hematopoietic stem cells(HSC).

METHODSThe MV from cultured BM-MSC supernatant were isolated by multi-step differential velocity contrifugation; the morphological characteristics of MV were observed by electron microscopy with negative staining of samples; the protein level in MV was detected by using Micro-BCA method; the surface markers on MV were analyzed by flow cytometry. The peripheral blood HSC(PB-HSC) were isolated after culture and mobilization; the experiment was diveded into 2 group: in MV group, the 10 mg/L MV was given, while in control group, the same volume of PBS was given; the change of PB-HSC count was observed by cell counting; the change of surface markers on PB-HSC was detected dynamically by flow cytometry; the cell colony culture was used to determin the function change of PB-HSC after co-culture with MV.

RESULTSMSC-MVs are 20-100 nm circular vesicles under electron microscope. About 10 µg protein could be extracted from every 1×10MSC. The flow cytometry showed that CD63 and CD44 were positive with a rate of 96.0% and 50.2%, while the HLA-DR, CD34, CD29 and CD73 etc were negative. When being co-cultured with GPBMNC for 2 days, the cell number of MV groups was 1.49±0.15 times of the control group (P>0.05). When being co-cultured for 4 days, the cell number of MV groups was 2.20±0.24 times of the control group(P<0.05). The CD34cell number of MV groups was 1.76±0.30 times the control group after culture for 2 day and 1.95±0.20 times after culture for 4 day.

CONCLUSIONThe MV has been successfully extracted from MSC culture supernatant by multi-step differential velocity centrifugation. MSC-MV can promote HSC expansion in vitro.