Objective To investigate the effects of epidural spinal cord electrical stimulation (ESCES) on spinal cord reflexes in normal adult rats, and to find out where and how the spinal cord reflexes are generated. Methods Ten adult female Sprague Dawley rats were anaesthetized and an electrode was placed at the S, spinal cord segment. Single electric pulses with 200 μs pulse width and voltages of 400 mV, 600 mV and 1200 mV were used in the ESCES. 1200 mV voltages with 50 Hz, 60 Hz, 80 Hz, 100 Hz frequency were also tested. EMG signals were re-corded with concentric needle electrodes in the rats' semitendinosus muscles to observe the characteristics of spinal cord reflexes. Results The voltage threshold for generating semitendinosus muscle response was 300 mV. The three ESCES voltages induced 2 kinds of spinal cord reflexes. The 400 mV and 600 mV stimulation induced spinal cord reflexes with short latency (5.27±0.36 ms and 5.19±0.67 ms respectively). The 1200 mV stimulation volt-age induced spinal cord reflexes with long latency (2.57±0.23 ms). Spinal cord reflexes could be generated by 50 Hz, 60 Hz, 80 Hz, and 100 Hz ESCES. At the higher frequencies, spinal cord reflexes declined late in the ex-periments and then appeared irregular. In some of the rats, spinal cord reflexes vanished entirely late in the stimula-tion experiments. The latency and duration of the spinal cord reflexes induced by 50 Hz ESCES were (4.46 ± 1.07) ms and (7.33±1.00)ms respectively. These were significantly different from the latency and duration initia-ted by 60 Hz, 80 Hz or 100 Hz ESCES. Conclusions Different ESCES voltages induce different spinal cord refle-xes generated differently. The long latency reflexes might be monosynaptic responses mediated by dorsal root excite-ment, while the short latency reflexes might be sarcous exciting electric activity mediated by direct excitement of mo-tor neurons or motor fibers. The irregular spinal cord reflexes induced by higher frequency ESCES might be one kind of monosynaptic response. Irregularly appearing spinal cord reflexes induced by higher frequency stimulation might due to the inhibitory effect of higher frequency stimulation.

Objective:To investigate the effects of epidural spinal cord stimulation (ESCS) and treadmill training on the locomotion function and ultrastructure of spinal cord anterior horn after moderate spinal cord injury in rats. (IT, n=3). All rats received a moderate spinal cord injury surgery. Four weeks after surgery, rats in SE group received an electrode implantation procedure, with the electrode field covering spinal cord segments L2-S1. Four weeks after electrode implantation, rats received subthreshold ESCS for 30 min/d. Rats in TY group received 4cm/s treadmill training for 30min/d. Rats in SI group received no intervention, as a control group. All procedures in these three groups lasted four weeks.The open field Basso,Beattie and Bresnahan (BBB) scale was used before and after intervention to evaluate rats' hindlimb motor function. Result:After four weeks intervention, rats in TT group improved their open field locomotion scores to 20. In contrast, no significant improvement was observed in groups SI and SE. The morphology of synapses and neurons were similar regardless of whether rats had undergone ESCS, treadmill training or not. Conclusion:ESCS alone was not sufficient to improve the walking ability of spinal cord injured rats. ESCS or treadmill training alone might not contribute to the changes of ultrastructure in anterior horn of spinal cord that underlie the recovery of walking ability. Further research is needed to understand the contributions of combination of ESCS and treadmill training to the rehabilitation of spinal cord injured rats.

Objective To investigate the role of endogenous Hydrogen Sulfide (H2S) in airway inflammation and responsiveness in a rat model of chronic passive-smoking.Methods Male SD rats were randomly divided into a control group (breathing fresh air) and a passive smoking group [cigarette smoking (CS) passively] ,with 18 rats in each group.Six rats in each group were randomly intraporitoneally injected with normal saline, sodium hydrosulfide (NailS) or propargylglycine (PPG, an irreversible inhibitor of cystathionine-γ-lyase).The animals were divided into six subgroups,ie.Con group, Naris group, and PPG group, CS group, CS + Naris group, and CS + PPG group.After 4 months,lung histological change and airway tension were measured.The H2 S levels of plasma and lung tissue were analyzed by the sensitive sulphur electrode assay.The expression of cystathionine-γ-lyase (CSE) was measured by western blot.Results Compared with the Con group, CSE protein expression in lung tissues was increased in CS group(P < 0.05) ; the H2S levels of plasma were significantly higher in GS group,NariS group and CS + Naris group,and much lower in PPG group (P < 0.05, respectively).Compared with CS group, the H2 S levels of plasma were significantly higher in CS + Naris group, and much lower in CS + PPG group (P < 0.05, respectively).The H2S level of lung tissue in each group had no significant difference (P > 0.05).Compared with Con group, score of lung pathology was significant elevated, and the responsiveness of airway smooth muscles to Ach and KCI was significant augmented in CS group.Compared with CS group, the score of lung pathology was decreased, and the responsiveness of airway smooth muscles was decreased in CS + NariS group(P < 0.05), and vise versa in CS + PPG group (P < 0.01).Conclusion H2 S can alleviate airway inflammation and hyperresponsiveness induced by CS, and administration of H2S might be of clinical benefit in airway inflammation and airway responsiveness.

Objective To analyze the epidemiology and clinical characteristics of acquired immunodeficiency syndrome (AIDS) and pulmonary tuberculosis (TB) co-infection.Methods A retrospective study was conducted with the clinical data of patients diagnosed with AIDS and TB in Shanghai Public Health Clinical Center during the period from 2011 to 2015.The outcome of the patients were evaluated by outpatient and telephone follow-up.The data were analyzed by descriptive analysis using SPSS 22.0 software package.Results A total of 359 patients with AIDS/TB co-infection were included in this analysis,including 325 males and 34 females,the highest proportion in 30-44 age group.The diagnosis was delayed in about 42.6％ of the patients.The clinical symptoms were mainly fever,cough and weight loss,but hemoptysis uncommon.Both lungs were affected in most cases,with lesions in at least 3 lung fields,but rare pulmonary cavity.T-SPOT.TB test showed lower positive rate.CD4+T lymphocyte count was 50 cells/μL or less in 50.7％ of the patients at their first test.About 43.5％ of the 69 patients with antimicrobial susceptibility data showed resistance to therapy.Majority (93.2％) of the patients with known viral status received antiretroviral treatment.Extra-pulmonary tuberculosis was identified in 282 cases.The complication and opportunistic infection included central nervous system infection,syphilis,hepatitis B virus infection,hepatitis C virus infection,pulmonary infection,and drug-induced liver injury.Of the 333 patients with known outcome,53 died,most (79.2％,42/53) within 6 months.Conclusions The patients with AIDS/TB co-infection showed higher proportion of young people.The CT finding was atypical.The patients showed lower positive rate for T-SPOT TB test and lower CD4+T lymphocyte count at their first test.Most patients had extra-pulmonary tuberculosis and other complications or opportunistic infections.

Objective To investigate the clinical characteristics and treatment strategies of arachnoid cyst combined with chronic subdural hematoma.Methods Seventeen patients with arachnoid cyst combined with chronic subdural hematoma,who received treatment in our hospital from February 2008 to March 2016,were chosen in our study;13 of them were performed burr hole irrigation and drainage,2 received craniotomy for removing hematoma and cystectomy,and 2 received endoscopic cyst excision and hematoma removal surgery.A retrospectively analysis of clinical characteristics and treatment strategies of these patients was performed.Results Follow up for 0.5-2 years was performed in the 13 patients performed burr hole irrigation and drainage,and no hematoma relapse was noted;one was found rebleeding in the cyst associated with a small amount of subdural hematoma on the 5th d of surgery,and the subdural hematoma was absorbed during the follow-up observation;one was found that the cyst and subdural hematoma both disappeared in the postoperative check,while the cyst reappeared 40 days after surgery,and during the follow-up observation,the cyst was not enlarged and the chronic subdural hematoma was not relapsed.Two patients recovered after receiving the craniotomy for removing hematoma and cystectomy;two patients recovered after receiving the endoscopic cyst excision andhematoma removal surgery.Conclusion For patients with arachnoid cyst associated with chronic subdural haematoma,burr-hole irrigation and drainage are generally selected;for patients with reappeared cyst or hematoma,there is no need to burr hole again or perform the surgery aiming at the cyst in a haste,and follow-up observation is suggested;for patients whose symptoms in the cyst have appeared before hemorrhage or whose hemorrhage appeared recurrently in the cyst,surgery of hematoma removal and cyst excision can be chosen at the same time.

Objective To determine the electrocardiographic (ECG) characteristics of myocardial infarction (MI) evolution in rats and the intervention effect of Chinese herbs, and to provide basis for the establishment of the criteria for ECG diagnosis and assessment of drug therapeutic effects of rats MI. Methods Totally 140 male SD rats were randomly divided into sham operation group, model group, replenishing qi group, activating blood group, replenishing qi and activating blood (1∶2) and (2∶1) group as well as Tongxinluo group, each group with 20 rats. The rat MI model was established by ligating the left anterior descending coronary artery. The treatment groups were administrered with corresponding drugs by gavage from the first day after operation. The sham operation group and model group were given the same volume of distilled water. The 12-lead ECGs were recorded before, immediately after, 1st and 2nd week after operation respectively. The voltage value of ST segment deviation, the time limit of QRS complex and the number of animals with pathologic Q wave were evaluated for statistical analysis. Results Model group showed the elevation of ST segment, significantly prolonged time limit of QRS complex (P<0.01), and no pathologic Q wave showed immediately after operation compared with sham operation group. And all above observational indexes reached the peak at 1st week and declined at 2nd week after operation. Compared with model group at 2nd week after operation, replenishing qi and activating blood (1∶2) group and (2∶1) group all presented remarkable dropping of ST segment, shortening in time limit of QRS complex and reduction in number of rats with pathologic Q wave, of which 2∶1 group showed the most (P<0.01). Activating blood group only displayed decreases in time limit of QRS and number of rats with pathologic Q wave (P<0.05), and no significant decline in ST segment. Replenishing qi group demonstrated no significant changes in above three observational indexes (P>0.05). Thus, we proposed the criterion for the ECG diagnosis of rats MI as well as the criterion for the ECG assessment of drug therapeutic effects of rats MI. Conclusion ECG can overall and sensitively evaluate the evolution and drug therapeutic effects of MI in rats, thus providing a relatively objective and available assessment method for the experimental studies of myocardial ischemic diseases.

PD-L1 is a member of the B7 protein family, most of whose members so far were identified as dimers in a solution and crystalline state, either complexed or uncomplexed with their ligand(s). The binding of PD-L1 with its receptor PD-1 (CD279) delivers an inhibitory signal regulating the T cell function. Simultaneously with the Garboczi group, we successfully solved another structure of human PD-L1 (hPD-L1). Our protein crystallized in the space group of C222(1) with two hPD-L1 molecules per asymmetric unit. After comparison of reported B7 structures, we have found some intrinsic factors involved in the interaction of these two molecules. Based on these results, we tend to believe this uncomplexed hPD-L1 structure demonstrated its potential dimeric state in solution, although it could just be an evolutionary relic, too weak to be detected under present technology, or still a functional unit deserved our attentions.
Antigens, CD ; chemistry ; immunology ; B7-H1 Antigen ; Crystallography, X-Ray ; Evolution, Molecular ; Humans ; Protein Multimerization ; Protein Structure, Quaternary ; Protein Structure, Secondary ; T-Lymphocytes ; chemistry ; immunology

Objective To investigate the correlation between the manual compression on injection point and the incidence of subcutaneous bleeding after subcutaneous injection of low molecular weight heparin(LMWH)in elderly patients with coronary artery disease.Methods A total of 131 elderly patients with coronary artery disease,who received subcutaneous injection of LMWH after percutaneous coronary intervention(PCI)at the Affiliated Nanjing Hospital of Nanjing Medical University of China between January 2019 and December 2021,were enrolled in this study.According to whether the manual compression on the injection point was employed or not after the injection of LMWH,the patients were divided into the study group(n=67)and the control group(n=64).The operation process of subcutaneous injection of LMWH was carried out in accordance with the"Supervision Standard for Nursing Quality of Hypodermic Injection of Low Molecular Weight Heparin"which was included in the norms formulated by authors'hospital.For the patients of the study group,the injection point was manually pressed for 3-5 min after the injection of LMWH,the manually-used force was to press the skin down for 1cm deep.The incidence of subcutaneous bleeding was compared between the two groups.Results In the study group and the control group,the incidence of subcutaneous ecchymosis was 9.0%and 7.8%respectively,the incidence of subcutaneous hard tubercle was 4.5%and 1.6%respectively,the differences between the two groups were not statistically significant(both P＞0.05).The patient's age,gender,abdominal circumference and body mass index(BMI)carried no obvious correlation with the subcutaneous bleeding after LMWH injection(P＞0.05),while a statistically significant correlation existed between the abdominal wall fat thickness and the subcutaneous bleeding(P＜0.05),which could be used as an independent predictor for the occurrence of subcutaneous bleeding after LMWH injection.Conclusion No obvious correlation exists between the manual compression on injection point and the incidence of subcutaneous bleeding in elderly patients with coronary artery disease after subcutaneous injection of LMWH,therefore,no compression manipulation,used as a hemostatic measure,is required after subcutaneous injection of LMWH.The abdominal wall fat thickness is an independent predictor for subcutaneous bleeding after injection of LMWH.Standard operation procedures should be strictly followed so as to avoid the occurrence of subcutaneous bleeding after injection of LMWH.(J Intervent Radiol,2024,32:77-81)

Protein A and protein G are two well-defined immunoglobulin (Ig)-binding proteins (IBPs), which show affinity for specific sites on Ig of mammalian hosts. Protein A and protein G contained several highly homologous IgG-binding domains which had been demonstrated to have function to bind to IgG. Whether combinations of Ig-binding domains of various IBPs could produce useful novel binding properties remains interesting. We constructed a combinatorial phage library which displayed randomly-rearranged A, B, C, D and E domains of protein A, B2 and B3 domains of protein G. Four rounds molecular evolution of this library directed by all four human IgG subclasses respectively generated a common arrangement of D-C respectively which didn't exist in SpA. The dynamic loss of control phages and increase of the phages displaying two or more binding domains, especially the selective enrichment of D-C and strict selection of its linking peptides demonstrated the efficient molecular evolutions and the significance of the selected D-C arrangement. The phage binding assays confirmed that D-C possessed a binding advantage with four human IgG subclasses compared to SpA. In this work, a novel combination of Ig-binding domains, D-C, was obtained and presented the novel Ig binding properties which provided a novel candidate molecule for the purification, production and detection of IgG antibodies and a new approach for the further study of structures and functions of IBPs.
Amino Acid Sequence ; Antibody Specificity ; Bacterial Proteins ; immunology ; metabolism ; Binding Sites ; Binding, Competitive ; Evolution, Molecular ; Immunoglobulin G ; immunology ; metabolism ; Molecular Sequence Data ; Peptide Library ; Sequence Alignment ; Staphylococcal Protein A ; immunology ; metabolism

We constructed a phage-displayed random mutation library of Tat38-61(51N/55N), for studying the molecular evolution screening of HIV-1 Tat38-61 epitope. We used primers containing the random nucleotide sequences, and introduced the random mutations at the sites of 51 and 55 amino acids coding sequences into full-length Tat sequences by overlapping PCR. With the randomly mutated full-length Tat as template, the Tat38-61(51N/55N) mutants which contained recognition sequences for the Xba I in both ends were amplified by PCR using the designed primers. The mutants were cloned into Xba I site in the phagemid vector pCANTAB5S, then the recombinants were transformed into E. coli TG1, a phage-displayed the random mutation library of Tat38-61(51N/55N) was constructed by the rescue of help virus M13KO7. The results showed that the library consisted of about 5.0 x 10(6) colonies and the phage library titer was 2.65 x 10(12) TU/mL. More than 56.50% colonies in the library were positive for insertion. Sequence analysis showed that the nucleotides encoding amino acids at the sites of 51 and 55 distributed randomly. The constructed mutation library could meet the requirements for the following molecular evolution screening, and might prepare the Tat mutants for the further study of new Tat vaccine candidates.
AIDS Vaccines ; immunology ; Escherichia coli ; genetics ; metabolism ; HIV-1 ; genetics ; Humans ; Mutation ; Peptide Fragments ; biosynthesis ; genetics ; immunology ; Peptide Library ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; tat Gene Products, Human Immunodeficiency Virus ; biosynthesis ; genetics ; immunology