Serum antibody levels in COVID-19 patients six months after hospital discharge / 上海预防医学

ObjectiveTo investigate the level of serum antibodies in COVID-19 patients six months after discharge， and to provide data to evaluate the duration of IgM， IgG and neutralizing antibody titers in the patients. MethodsEnzyme-linked immunosorbent assay （ELISA） was used to determine the antibody levels of IgM and IgG， and the new coronavirus live virus neutralization test was used to detect the neutralizing antibodies in the plasma of 181 recovered patients. ResultsThe IgG positive rate was 92.27% （167/181） in COVID-19 patients six months after discharge， while the lgM positive rate was 28.18% （51/181）. Six months after hospital discharge， 117 recovered patients （64.64%） were positive for IgG antibodies and negative for IgM antibodies， indicating that they had produced stable antibodies. This result suggested that they had been infected with the new coronavirus （SARS-CoV-2） and were in the recovery stage. The positive detection rate of neutralizing antibodies was as high as 91.71%. ConclusionSix months after infection with SARS-CoV-2， IgG antibodies produced in the patients continue to exist， and the neutralizing antibodies maintain a high and stable level. Results of this study have important guiding significance for future research on the durability of new coronavirus antibodies.

Serum antibody levels in COVID-19 patients six months after hospital discharge / 上海预防医学

ObjectiveTo investigate the level of serum antibodies in COVID-19 patients six months after discharge， and to provide data to evaluate the duration of IgM， IgG and neutralizing antibody titers in the patients. MethodsEnzyme-linked immunosorbent assay （ELISA） was used to determine the antibody levels of IgM and IgG， and the new coronavirus live virus neutralization test was used to detect the neutralizing antibodies in the plasma of 181 recovered patients. ResultsThe IgG positive rate was 92.27% （167/181） in COVID-19 patients six months after discharge， while the lgM positive rate was 28.18% （51/181）. Six months after hospital discharge， 117 recovered patients （64.64%） were positive for IgG antibodies and negative for IgM antibodies， indicating that they had produced stable antibodies. This result suggested that they had been infected with the new coronavirus （SARS-CoV-2） and were in the recovery stage. The positive detection rate of neutralizing antibodies was as high as 91.71%. ConclusionSix months after infection with SARS-CoV-2， IgG antibodies produced in the patients continue to exist， and the neutralizing antibodies maintain a high and stable level. Results of this study have important guiding significance for future research on the durability of new coronavirus antibodies.

Correlation between FOXP3, CD11c Protein Expression and Prognosis of Patients with Diffuse Large B-cell Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To investigate the correlation between FOXP3, CD11c protein expression and the prognosis of patients with diffuse large B-cell lymphoma (DLBCL).@*METHODS@#This study included 48 patients with DLBCL who were admitted to Jiujiang No.1 People's Hospital and TCM-Integrated Hospital of Southern Medical University from January 2015 to January 2019. The DLBCL tissues removed during the operation were collected as test specimens. The expression of FOXP3 and CD11c protein were detected by immunohistochemistry. The deadline for postoperative follow-up was December 31, 2019, and the patient's short-term efficacy (complete remission, partial remission) and progression-free survival were recorded.@*RESULTS@#FOXP3 protein was positively expressed in the nucleus, mostly focally or diffusely distributed, the FOXP3@*CONCLUSION@#In some patients with DLBCL, FOXP3 and CD11c expresse positively, and the positive expression rate is related to the clinical stage and international prognostic index score. The positive expression of FOXP3 and CD11c indicate a good prognosis.

Effects of activation or blockade of 5-HT1A receptors in the medial septum-diagonal band of Broca complex on cognitive functions in hemiparkinsonian rats / 西安交通大学学报(医学版)

Objective To explore the role and mechanisms of 5-HT1Areceptors in the medial septum-diagonal band of Broca complex (MS-DB) in hemiparkinsonian rats. Methods Combined behavioral and electrophysiological studies were performed to assess the role of MS-DB 5-HT1Areceptors in working memory and hippocampal theta rhythm in rats with 6-hydroxydopamine (6-OHDA)lesions in the medial forebrain bundle (MFB).Results ① MFB lesions in the rats decreased choice accuracy in the T-maze rewarded alternation test. Intra-MS-DB injection of 5-HT1Areceptor agonist 8-OH-DPAT further decreased choice accuracy,while intra-MS-DB injection of 5-HT1Areceptor antagonist WAY-100635 increased choice accuracy in the lesioned rats.② MFB lesions in the rats decreased peak theta rhythm frequency. Intra-MS-DB injection of 8-OH-DPAT suppressed hippocampal theta rhythm and decreased normalized theta power,while intra-MS-DB injection of WAY-100635 induced theta rhythm and increased normalized theta power.Conclusion Blockade of MS-DB 5-HT1Areceptors can recover cognitive dysfunction in Parkinson's disease, which may be attributed to the enhancement of hippocampal theta rhythm.

Multiple primary sarcomatoid carcinoma of the jejunum with postoperative lung and brain metastases: a case report and literature review / 南方医科大学学报

We report a rare case of a multiple sarcomatoid carcinoma of the jejunum with postoperative lung and brain metastases. The patient underwent jejunum segmental resection for intussusception and gastrointestinal bleeding. Multiple metastasis ofbrain and lung occurred 4 months after the operation, and the patient died for multiple organ failure 8 months after the surgery. Primary sarcomatoid carcinoma was difficult to diagnose at an early stage, and the diagnosis relies on optical microscopic and immunohistochemical observations. Currently no guidelinesare established for treatment for sarcomatoid carcinoma of the jejunum, and surgical resection remains the optimal therapeutic approach. Previous reports documented a poor prognosis of the patients with a median survival time of 5.5 months (0.36-36months), and the primary causes of death were tumor recurrence and metastasis. Ki-67 as a potential prognostic marker and the value of PD-L1-targeted immunotherapy for the treatment await further investigation.

Inhibitory effect of photodynamic therapy combined with paclitaxel on the proliferation of esophageal carcinoma Eca-109 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the inhibitory effect of photodynamic therapy (PDT) in combination with paclitaxel (PCT) on proliferation in esophageal carcinoma Eca-109 cells line.</p><p><b>METHODS</b>Eca-109 cells were treated with PCT alone, HPD alone at different doses, or their combinations. For the combined treatments, the cells were exposed to PCT for 12 h followed by incubation with HPD at high, middle or low concentrations for 4 h. PDT was then performed on these treated cells and fluorescence microscopic observation was made before and after PDT. The cell survival was measured by MTT assay, and the cell apoptosis rate analyzed by flow cytometry after a 24-h cell incubation following PDT.</p><p><b>RESULTS</b>The fluorescence excitation of the cells was weakened after PDT. Combined treatments resulted in significantly lowered cell survival rate and increased cell apoptosis rates as compared to those of the control cells and the cells treated with PCT alone and low-dose HPD (P<0.01). Significant differences were also noted among the cells exposed to HPD at different concentrations (P<0.05).</p><p><b>CONCLUSION</b>PDT combined with PCT have significant synergetic effects in inhibiting the proliferation of human esophageal carcinoma cells and inducing their apoptosis in vitro.</p>

Mechanism of photodynamic therapy against human esophageal carcinoma xenografts in nude mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the mechanism of photodynamic therapy (PDT) in nude mice bearing human esophageal cancer cell line Eca-109 xenografts.</p><p><b>METHODS</b>A nude mouse model bearing human esophageal carcinoma was established by subcutaneous transplantation of Eca-109 cells. The mice were then randomized into 4 groups, namely hematoporphyrin derivative (HpD)-PDT group (given HpD and laser irradiation), exclusive laser irradiation group, exclusive HpD group and blank control group. In HpD-PDT group, the mice were exposed to irradiation at the light energy density of 120 Jsol;cm(2) delivered via a DIOMED 630 PDT system 24 h after intraperitoneal HpD injection, and the mice in exclusive laser irradiation group received only laser irradiation. Three days later, all the nude mice were sacrificed for determination of malondialdehyde (MDA) production, immunohistochemistry for caspase-3 protein and HE staining of the tumor tissue.</p><p><b>RESULTS</b>The MDA level was significantly higher in HpD-PDT group than in the other 3 groups (P<0.01), and comparable between the latter 3 groups. Expression of caspase-3 protein was similar between HpD-PDT group and the blank control group (P>0.05). Under light microscope, HE staining visualized massive tissue necrosis in HpD-PDT group with homogeneous red staining.</p><p><b>CONCLUSION</b>In human esophageal carcinoma xenografts in nude mice, HpD-PDT generates singlet oxygen to result in direct tumor cell damage and cause MDA production. Caspase-3 may not be activated in the apoptotic pathway, suggesting that this pathway may not be caspase-3-dependent.</p>

Biology of thioredoxin and its association with Alzheimer's disease and Parkinson's disease / 药学学报

Thioredoxin (Trx) is a crucial protein for antioxidative defense, as well as a redox regulator of the intra- and extracellular signaling pathways and transcription factors. In this review, we focus on mammalian Trx and its association with Alzheimer's disease (AD) and Parkinson's disease (PD). Based on the evidence of neuroprotective effects of Trx, up-regulation of Trx may be a good strategy for prevention and treatment of AD and PD.

Main factors affecting the effect of photodynamic therapy against human esophageal cancer cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the tumor cell-killing effect of photodynamic therapy against human esophageal cancer cells in vitro and identify the main factors affecting the effect.</p><p><b>METHODS</b>Human esophageal cancer Eca-109 cells were incubated for 24 h in vitro with hematoporphyrin derivative (HpD) and Photofrin at different concentrations prior to exposure to a light energy density of 15 J/cm(2) delivered from a DIOMED 630 PDT system. The cell killing effect was also evaluated for different HpD concentrations combined with 3 light energy densities (10, 30, and 50 J/cm(2)), respectively. The cell survival rate was measured using MTT assay, and fluorescence spectrometry was used to detect the intracellular photosensitizer fluorescence of the tumor cells after incubation with HpD for 4 h.</p><p><b>RESULTS</b>The cell survival rate after incubation with the two photosensitizers at different concentrations were significantly different, and under the 3 different light energy densities, incubation of the cells with different HpD concentrations also resulted in significantly different cell survival rates (P<0.05). At the 4 low photosensitizer concentrations and with different light energy densities, the cell survival rates were similar (P>0.05), but the 4 higher photosensitizer concentrations resulted in significant difference in the cells survival (P<0.05). Correlation analysis showed that the intracellular photosensitizer concentration was positively correlated to the photosensitizer concentrations in cell incubation (r=0.997).</p><p><b>CONCLUSION</b>When the light source remains constant, the light energy density, the kinds of photosensitizers and their concentrations are the main factors affecting the Eca-109 cell-killing effect of PDT.</p>

Hematoporphyrin derivative-mediated photodynamic therapy for human nasopharyngeal carcinoma: a comparative study with CNE2 and C666-1 cell lines in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate biological effect of hematoporphyrin derivative (HpD) photodynamic therapy (PDT) on in vitro cultured nasopharyngeal carcinoma (NPC) cell lines CNE2 and C666-1.</p><p><b>METHODS</b>CNE2 and C666-1 cells cultured in vitro were incubated in a medium containing HpD at different concentrations (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 microg/ml) for 4 h followed by exposure to different light doses (2, 5, 10, and 20 J/cm2) using a diode laser at 630 nm with power density of 20 mW/cm2. After 24 h of incubation with HpD-PDT, the survival rate of CNE2 and C666-1 cells were analyzed by MTT assay.</p><p><b>RESULTS</b>HpD-PDT produced effective killing of CNE2 and C666-1 cells cultured in vitro, and the killing effects were positively correlated with HpD concentration and the irradiation dose. Exposure of CNE2 and C666-1 cells to irradiation dose of 20 J/cm2 resulted in the IC50 of 0.7 and 1.2 microg/ml, respectively (P<0.01). With the same HpD concentration and irradiation dose, the survival rate of C666-1 cells, however, was significantly higher than that of CNE2 cells (P<0.05).</p><p><b>CONCLUSION</b>HpD-PDT may result in effective killing of CNE2 and C666-1 cells cultured in vitro, although C666-1 cells are less sensitive to HpD-PDT than CNE2 cells.</p>

Preparation of hematoporphyrin-herceptin photoimmunoconjugate for photoimmunotherapy / 南方医科大学学报

<p><b>OBJECTIVE</b>To prepare photoimmunoconjugate of hematoporphyrin (HP) and herceptin, and study its killing and apoptosis-inducing effect on tumor cells BT-474.</p><p><b>METHODS</b>HP-herceptin photoimmunoconjugate was synthesized with EDCI as the condensator. After exposure of the cells to 630 nm laser, the killing effect of the conjugate and cell apoptosis were evaluated by MTT assay and flow cytometry.</p><p><b>RESULTS</b>Compared with free HP at equivalent dose, the immune reactivity, killing effect and the apoptosis-inducing effect of HP-herceptin immunoconjugate on BT-474 cells was enhanced (P<0.05).</p><p><b>CONCLUSION</b>The killing effect of HP-herceptin immunoconjugate is stronger than free HP on BT-474 cells.</p>

Construction of adeno-associated virus vector carried mutated dihydrofolate reductase and green fluorescent protein and its expression in NIH3T3 cells / 中国实验血液学杂志

The aim of this study was to construct recombinant mDHFR-GFP/AAV vector containing mutated dihydrofolate reductase (mDHFR) and green fluorescent protein (GFP) fusion genes and its expression in NIH3T3 cells, to investigate the resistance of the cells to methotrexate. Amplified cDNA of mDHFR and GFP segmented from their plasmid separately were linked by PCR with the aminoacetic acid linker. The fusion gene was inserted into T vector, and after enzyme cutting the fusion gene fragment was inserted into AAV vector, then packaging the vector into recombined AAV and infected NIH3T3 cells. Expression of gene fusion was observed by PCR, fluorescent microscopy and flow cytometry. mDHFR and GFP cDNA were found in NIH3T3 genomic DNA, the GFP expression rate was about 25%, and resistance of the transferred cells to MTX was increased markedly. The results showed that AAV vector can transfer mDHFR and GFP fusion gene into NIH3T3 cells and increase resistance to MTX in gene modified cells. This data provided a basis for application of mDHFR and AAV vector in gene therapy.

VIesenteric lymph of shock rats activates peripheral neutrophils / 中国普通外科杂志

Objective To study the peripheral neutrophils activation mesenteric lymph in a murine hemorrhagic shock model.Methods In this study,18 male Sprague-Dawley rats were evenly divided into 3 groups.Group A:rats subjected to hemorrhagic-shock and Ringer's lactate(RL)resuscitation,group B:rats suffered from no blood loss but received same amount of RL as in group A,and group C:rats experience no blood loss nor RL transfusion.The main mesenteric lymphatic duct was cannulated with 24G catheter in all rats.In group A,blood was withdrawn through femoral artery until mean arterial pressure reached 40?5 mm Hg,the pressure was maintained for 90 min.In group B,no blood was withdrawn,these two groups received RL 3 times as the blood withdrawn,in group C,no blood was withdrawn,nor fluid was given.Lymph samples during pre-shock,the first hour and second hour post-shock or sham shock were collected and was used to induce PMN activation.Mesenteric lymph-induced rat PMN(polymorphonuclear neutrophil)adhesion molecule expression(CD18 and CD11b)and neutrophil respiratory burst activity was examined using a FACS flow cytometer.Results In group A,1st hour and 2 nd hour post-shock mesenteric lymph induced rat PMN activation,the expression of CD11b was 63.28?1.13%,61.23? 1.16%,respectively,compared with control(P