Objective:To explore the consistency of claudin 18.2 immunohistochemistry (IHC) using 4 different clone antibodies in gastric adenocarcinoma.Methods:A total of 226 gastric adenocarcinomas diagnosed and treated at the Drum Tower Hospital Affiliated to Nanjing University Medical College between January 2022 to March 2023 were included in this study. The cohort consisted of 165 males and 61 females, with a mean age of (61.3±12.1) years. Tumor tissues from radical resection specimens were collected for tissue microarrays. IHC detection of claudin 18.2 was performed using the EnVision method, utilizing 4 clones of antibody: OTIR157B5, 43-14A, EPR19202 and D313D22. The results were interpreted based on both the intensity of staining on tumor cell membranes and the percentage of positive tumor cells relative to the total tumor cells.Results:The positive cutoff value was set as moderately to strongly linear membrane staining in ≥75% of all viable invasive tumor cells, and clone OTIR157B5 demonstrated the highest positive expression rate at 52.2% (118/226). Additionally, the clones OTIR157B5, 43-14A, and EPR19202 were consistently and strongly positive, with all agreement rates of Cohen κ exceeding 0.8. In gastric adenocarcinoma and its three Lauren subtypes, OTIR157B5 exhibited clear membranous localization.Conclusions:Clone OTIR157B5 of claudin 18.2 antibody shows the highest rate of moderately to strongly linear membrane-positive staining, accounting for ≥75% of all viable invasive tumor cells, and clones 43-14A and EPR19202 show strong consistency and high sensitivity.

Objective:To investigate the neural regulatory mechanism of parvalbumin-positive interneurons(PV-INs)in the dentate gyrus(DG)involved in the impairment of spatial recognition memory by exercise-induced chronic fatigue.Methods:Male Sprague-Dawley(SD)rats were divided into control group and fatigue group by random num-ber method.A three-level incremental load treadmill training program was selected to establish a chronic exhaustion exercise fatigue model.The spatial recognition memory ability of rats was tested by novel object recognition test.The ac-tivation levels and quantitative changes of astrocytes(AS)and PV-INs in the DG region was observed and quantified through immunofluorescence staining and immunohistochemical staining.The phosphorylation level of calcium/calmodu-lin-dependent protein kinase Ⅱ(CaMK Ⅱ)in the hippocampus was detected by Western blot.Results:In the test of novel object recognition,the exploration time of novel object was reduced in the fatigue group,and the discrimination index was significantly lower than that in the control group(P＜0.01).Immunohistochemical staining showed that PV-INs in the DG region of fatigue rats were lighter and fewer than those in the control group,the fibers were short and sparse,and the positive cell density and average optical density of cells were significantly lower than those in the control group(P＜0.01).Immunofluorescence staining showed that AS was significantly activated,glial fibrillary acidic pro-tein(GFAP)was stained deeply,and the cell processes were dense and elongated in the DG region of fatigue rats.The positive cell density and mean fluorescence intensity were significantly higher than those of the control group(P＜0.01).The results of Western blot showed that the phosphorylation level of CaMK Ⅱ protein in the hippocampus of the fatigue group was significantly reduced than that of the control group(P＜0.01).Conclusion:Exercise-induced chro-nic fatigue inhibited PV-INs in the rat hippocampal DG region.The excessive activation of AS following exercise fatigue may be a major contributor to this PV-INs suppression.Concurrently,reduced phosphorylation levels of CaMK Ⅱ protein were observed in hippocampal tissue.These alterations ultimately impaired spatial recognition memory in the rats.

Objective:To investigate the neural regulatory mechanism of parvalbumin-positive interneurons(PV-INs)in the dentate gyrus(DG)involved in the impairment of spatial recognition memory by exercise-induced chronic fatigue.Methods:Male Sprague-Dawley(SD)rats were divided into control group and fatigue group by random num-ber method.A three-level incremental load treadmill training program was selected to establish a chronic exhaustion exercise fatigue model.The spatial recognition memory ability of rats was tested by novel object recognition test.The ac-tivation levels and quantitative changes of astrocytes(AS)and PV-INs in the DG region was observed and quantified through immunofluorescence staining and immunohistochemical staining.The phosphorylation level of calcium/calmodu-lin-dependent protein kinase Ⅱ(CaMK Ⅱ)in the hippocampus was detected by Western blot.Results:In the test of novel object recognition,the exploration time of novel object was reduced in the fatigue group,and the discrimination index was significantly lower than that in the control group(P＜0.01).Immunohistochemical staining showed that PV-INs in the DG region of fatigue rats were lighter and fewer than those in the control group,the fibers were short and sparse,and the positive cell density and average optical density of cells were significantly lower than those in the control group(P＜0.01).Immunofluorescence staining showed that AS was significantly activated,glial fibrillary acidic pro-tein(GFAP)was stained deeply,and the cell processes were dense and elongated in the DG region of fatigue rats.The positive cell density and mean fluorescence intensity were significantly higher than those of the control group(P＜0.01).The results of Western blot showed that the phosphorylation level of CaMK Ⅱ protein in the hippocampus of the fatigue group was significantly reduced than that of the control group(P＜0.01).Conclusion:Exercise-induced chro-nic fatigue inhibited PV-INs in the rat hippocampal DG region.The excessive activation of AS following exercise fatigue may be a major contributor to this PV-INs suppression.Concurrently,reduced phosphorylation levels of CaMK Ⅱ protein were observed in hippocampal tissue.These alterations ultimately impaired spatial recognition memory in the rats.

Objective:To explore the consistency of claudin 18.2 immunohistochemistry (IHC) using 4 different clone antibodies in gastric adenocarcinoma.Methods:A total of 226 gastric adenocarcinomas diagnosed and treated at the Drum Tower Hospital Affiliated to Nanjing University Medical College between January 2022 to March 2023 were included in this study. The cohort consisted of 165 males and 61 females, with a mean age of (61.3±12.1) years. Tumor tissues from radical resection specimens were collected for tissue microarrays. IHC detection of claudin 18.2 was performed using the EnVision method, utilizing 4 clones of antibody: OTIR157B5, 43-14A, EPR19202 and D313D22. The results were interpreted based on both the intensity of staining on tumor cell membranes and the percentage of positive tumor cells relative to the total tumor cells.Results:The positive cutoff value was set as moderately to strongly linear membrane staining in ≥75% of all viable invasive tumor cells, and clone OTIR157B5 demonstrated the highest positive expression rate at 52.2% (118/226). Additionally, the clones OTIR157B5, 43-14A, and EPR19202 were consistently and strongly positive, with all agreement rates of Cohen κ exceeding 0.8. In gastric adenocarcinoma and its three Lauren subtypes, OTIR157B5 exhibited clear membranous localization.Conclusions:Clone OTIR157B5 of claudin 18.2 antibody shows the highest rate of moderately to strongly linear membrane-positive staining, accounting for ≥75% of all viable invasive tumor cells, and clones 43-14A and EPR19202 show strong consistency and high sensitivity.

Objective To evaluate the risk factors and sonographic findings of pregnancies complicated by placenta increta or placenta percreta. Methods Totally, 2219 cases were retrospectively analyzed from 20 tertiary hospitals in China from January 2011 to December 2015. The data were collected based on the original case records. All cases were divided into two groups, the placenta increta (PI) group (79.1％, 1755/2219) and the placenta percreta (PP) group (20.9％, 464/2219), according to the degree of placental implantation. The risk factors and sonographic findings of placenta increta or percreta were analyzed by uni-factor and logistic regression statistic methods. Results The risk factors associated with the degree of placental implantation were age, gravida, previous abortion or miscarriage, previous cesarean sections, and placenta previa (all P<0.05), especially, previous cesarean sections (χ2=157.961) and placenta previa (χ2=91.759). Sonographic findings could be used to predict the degree of placental invasion especially the boundaries between placenta and uterine serosa, the boundary between placenta and myometrium, the disruption of the placental-uterine wall interface and loss of the normal retroplacental hypoechoic zone(all P<0.01). Conclusions Previous cesarean sections and placenta previa are the main independent risk factors associated with the degree of placenta implantation. Ultrasound could be used to make a prenatal suggestive diagnosis of placenta accreta spectrum disorders.

Clostridium difficile( C. difficile)is a major nosocomial infection pathogen and the principal causative agent of antibiotic-associated diarrhea. The toxigenic C. difficile strains cause colonic injury and inflammation mainly by secreting enterotoxin A( TcdA)and cytotoxin B( TcdB). The severity of C. difficile associated disease( CDAD)is correlated to the toxin level during host infection. However,the toxigenic capacity of C. difficile varies widely among strains,which correlates with the gene regulation involved during toxin production. This article reviewed the regulatory mechanism of C. difficile toxin-associated pathogenic gene and anti-toxin treatment.

Objective:To observe effect of acupuncture combined with hypothermia therapy on MAPK/ERK pathway and apoptosis related factorsin rats suffered cerebral ischemia reperfusion and to explore underlying mechanisms.Methods:Middle cerebral artery ischemia model were established.Ninety SD rats were randomly assigned into a blank group,a control group,a model group,an acupuncture group,a mild hypothermia group,and an acupuncture with hypothermia group.After 72 h treatment,nervefunction defect scores were observed,and infarction area percent was detected by 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining;expressions of Bcl-2 and Bax were examined by immunohistochemistry;apoptotic cells were detected by TUNEL assay;and expression levels of phospho-mitogen-activated protein kinase(p-MEK2) and phospho-extracellular signal regulated kinase 1/2 (p-ERK1/2) in the rats' hippocampus ischemic side were determined by Western blot.Results:In the rats of the model group,the neural function defect scores,the infarction area percent,the expression level of Bax,and apoptotic cells increased,while the level of Bcl-2 decreased significantly.The level of p-MEK2 and p-ERK1/2 increased obviously compared with the blank and control groups (P＜0.05 or P＜0.01).After treatment with acupuncture and hypothermia,the neural function defect scores,infarction area percent,and the level ofBax,apoptotic cells and the levels of p-MEK2 and p-ERK1/2 were significantly decreased,while the level of Bcl-2 in the treatment group was significantly elevated (P＜0.05 or P＜0.01) compared with the model group.Compared with the acupuncture group or the hypothermia group,the neural function defect scores and the levels of p-MEK2 and p-ERK1/2 in the acupuncture combined with hypothermia group were significantly reduced (P＜0.05 or P＜0.01).Conclusion:Acupuncture and hypothermia therapy can improve cerebral function,and reduce the cerebral injury through down-regulation of Bax level,and up-regulation of Bcl-2 level,which is related to reducing the levels of p-MEK2 and p-ERK1/2.The therapeutic effects on cerebral ischemia reperfusion injury for combination of acupuncture with hypothermia are better than those with single application of acupuncture or hypothermia.

Clostridium difficile (C.difficile) infection is the leading cause of hospital-acquired diarrhea and pseudomembranous colitis.C.difficile-associated disease (CDAD) is mediated mainly by two bacterial toxins, TcdA and TcdB, which cause the diarrhea, as well as colitis and even intestinal necrosis.It has been indicated that level of C.difficile toxin is an important factor influencing the clinical phenotype of CDAD, however, the exact association between toxin and clinical phenotype remains unclear.In this article, we summarized the clinical phenotype of CDAD, the structure, function and regulatory mechanism of C.difficile toxin and discussed the relationship between C.difficile toxin and clinical phenotype, which may help to understand the pathogenic mechanism and provide possible therapeutic target for C.difficile infection.

Objective: To investigate the effect of acupuncture plus mild hypothermia on neurological function impairment score, cerebral infarct size and apoptosis-related factors in cerebral ischemia reperfusion injury (CIRI) rats.Methods: Sixty healthy male Sprague-Dawley (SD) rats were routinely reared for 1 week. Ten rats were randomly selected as the sham operation group and 10 rats as the blank control group, while the remaining 40 rats were subjected to preparing the middle cerebral artery occlusion (MCAO) model by modified filament occlusion method. The 40 MCAO rats were further randomly divided into a model group, an acupuncture group, a mild hypothermia group and an acupuncture plus mild hypothermia group, with 10 rats in each group. Rats in the sham operation group, the blank control group and the model group did not accept treatment except binding; rats in the acupuncture group received acupuncture treatment; rats in the mild hypothermia group received mild hypothermia treatment; rats in the acupuncture plus mild hypothermia group received acupuncture and mild hypothermia treatment. 72 h after the treatment, neurological function impairment score was performed; the infarct area ratio was determined by 2,3,5-tripheyl tetrazolium chloride (TTC) staining; apoptosis of brain cells was observed by TUNEL method; the expressions of Bcl-2, Bax and Caspase-3 were detected by immunohistochemistry.Results: Compared with the blank control group and the sham operation group, the neurological function impairment score, cerebral infarct area ratio, apoptosis, and the expressions of Bax and Caspase-3 in the model group were significantly increased, while the expression of Bcl-2 was significantly decreased, and there were significant between-group differences (allP<0.05). After the treatment, there were statistically significant differences among the treatment groups in the neurological function impairment score, cerebral infarct area ratio and apoptosis in the ischemic side of rats, as well as the expressions of Bcl-2, Bax and Caspase-3 (allP<0.05), and from the figures, tables and statistical analysis, it was found that a better tendency in the acupuncture plus mild hypothermia group than the acupuncture group or mild hypothermia group.Conclusion: Acupuncture plus mild hypothermia can protect the brain cells by improving neurological function impairment, decreasing cerebral infarct area ratio, reducing the number of apoptotic cells in the ischemic area and regulating the expressions of apoptosis related proteins to inhibit apoptosis.

Objective:To observe the protective effect of acupuncture plus mild hypothermia on brain tissues in rats with cerebral ischemia-reperfusion injury (CIRI), and the influence on protein expression levels of phosphorylated Raf-1, MEK-2 and ERK1/2 in the mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinases (ERK) pathway, and to explore the mechanism of acupuncture plus mild hypothermia therapy for the ischemic stroke. Methods:Ninety Sprague-Dawley (SD) rats were randomly divided into a blank control group, a sham operation group, a model group, an acupuncture group, a mild hypothermia group and an acupuncture plus mild hypothermia group, 15 rats in each group. Except the rats in the blank control group, the remaining rats were used to prepare the middle cerebral artery occlusion (MCAO) models according to the modified occlusion method using lines, while only the occlusion lines were inserted without blocking the brain arteries of rats in the sham operation group. When the vital signs of rats were stable, rats in the blank control group did not receive any intervention; rats in the sham operation group and the model group received fastening without treatment; rats in the acupuncture group, the mild hypothermia group, and the acupuncture plus mild hypothermia group were treated with the corresponding therapeutic methods. 72 h later, observed neurologic injury score, evaluated infarction area ratio by 2,3,5-tripheyl tetrazolium chloride (TTC) staining, determined apoptosis by TUNEL assay, and measured the phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels in rat ischemic hippocampal tissues by Western blot assay. Results: Compared with the blank control group and the sham operation group, after modeling, the neurologic injury score, infarction area ratio and apoptotic cells were increased, and phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels were significantly increased in the model group; the differences were statistically significant (P<0.05 orP<0.01). Compared with the model group, after acupuncture or mild hypothermia therapy, neurologic injury score and infarction area ratio were decreased; apoptotic cells and phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels were significantly decreased; the differences were statistically significant (P<0.05 orP<0.01). Compared with the acupuncture group, neurologic injury score and phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels were decreased in the acupuncture plus mild hypothermia group; differences between the groups were statistically significant (P<0.05 or P<0.01). Compared with the mild hypothermia group, phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels decreased in the acupuncture plus mild hypothermia group, and differences were statistically significant (P<0.01). Conclusion:Acupuncture or mild hypothermia therapy can improve neurologic injury, reduce infarction area and apoptosis, which brought about protective effect on the brain tissues, in the MCAO model. The protective effect of acupuncture plus mild hypothermia group is the strongest. The mechanism may involve the MAPK/ERK pathway, by reducing the phosphorylated Raf-1, MEK-2 and ERK1/2 protein expression levels.