Objective: To summarize the laboratory findings of a case of hemolytic disease of the fetus and newborn (HDFN) caused by Rh system anti-c antibodies and to review the literature, so as to explore the characteristics of anti-c HDFN. Methods: The ABO blood type, Rh blood type, direct antiglobulin test (DAT) results, and the presence of unexpected antibodies and their titers were determined by serological methods. The cases of anti-c HDFN in our laboratory in China and abroad were statistically analyzed, and the incidence of severe HDFN caused by anti-c, anti-D and anti-E was compared. Results: The blood type of the child was B (Rh CcDee) with a positive DAT. Anti-c antibody was detected in both serum and eluate, with a serum antibody titer of 4. The mother’s blood type was AB (Rh CCDee) with a negative DAT, and anti-c antibody was detected in the serum with a titer of 128. Among 20 cases of anti-c HDFN, 17 were DAT positive, and 9 (45%, 9/20) underwent blood transfusion or exchange transfusion. The incidence of severe HDFN was 47.60% (10/21) for anti-c, 47.60% (10/21) for anti-D and 31.30% (5/16) for anti-E. Conclusion: Maternal pregnancy and/or blood transfusion are the main reasons for the production of Rh alloantibodies such as anti-c. The prevention and management of anti-c should be similar to that of anti-D. Rh antigen-matched (five antigens of Rh blood group) transfusion is necessary for women of childbearing age to avoid antibody production, and Rh typing and antibody screening during prenatal examination is recommended to ensure early detection, intervention and treatment.

Objective:To preliminarily investigate the applicability of a poliovirus pseudovirus-based neutralization assay in evaluating the immunogenicity of recombinant poliovirus vaccines and their in vivo potency in rats. Methods:Serum samples from rats immunized with recombinant poliovirus vaccines were tested using both the pseudovirus neutralization assay and the live-virus neutralization assay with Sabin strain. The consistency and correlation of the two methods were analyzed using the Kappa test and Spearman′s rank correlation.Results:For the neutralizing antibodies against typeⅠ, Ⅱ, and Ⅲ polioviruses, the Kappa values for consistency analysis of the two methods were 0.914, 1.000, and 0.751, respectively ( P<0.001), and the correlation coefficients ( R values) were 0.833, 0.927, and 0.859, respectively ( P<0.001). Conclusions:The test results of the two methods are consistent and show a good correlation, indicating that the pseudovirus neutralization assay can be applied to evaluating the immunogenicity of poliovirus vaccines and also can be used in rat potency tests.

Objective:To systematically evaluate the prevalence of norovirus causing sporadic acute gastroenteritis in China.Methods:Relevant articles on acute gastroenteritis caused by norovirus in China published between January 2010 and October 2023 were retrieved from Wanfang, CNKI and PubMed database. The articles met inclusion and exclusion criteria were enrolled in this study. Excel software and SPSS20.0 software were used for statistical analysis. The epidemiological features of sporadic cases of acute gastroenteritis caused by norovirus in China were summarized using descriptive statistical analysis.Results:A total of 500 articles were included in this study, involving 784 486 cases of acute gastroenteritis and 670 292 samples in 32 provinces and regions. Norovirus GⅡ was the predominant genogroup causing acute gastroenteritis in China in recent years, but there were significant differences in the distribution of genotypes and epidemic strains at different times. GⅡ.4 was the predominant genotype in each year, and GⅡ.4/2006b and GⅡ.4 /Sydney_2012 were the main epidemic strains. Norovirus-related diarrhea occurred throughout the year, especially between the months of October and December. The incidence of norovirus infection was high in children under five years old and varied in different regions.Conclusions:Norovirus GⅡ was the predominant genogroup causing norovirus-related sporadic acute gastroenteritis in China, but there was an obvious genetic evolutionary trend in the epidemic strains. Factors such as epidemic strains, season and geographical region should be considered when making strategies for the prevention and control of norovirus-related diarrhea and developing vaccines.

Hypervirulent Klebsiella pneumoniae (HvKP) is a new variant of Klebsiella pneumoniae. It is characterized by strong virulence and easy dissemination. It mainly causes liver abscess with multiple invasive infections, including eye, lung and central nervous system, with a high fatality rate. A case of severe intracranial infection caused by HvKP was reported. The patient was a 44-year-old formerly healthy man. He had acute onset of fever, headache, and disturbance of consciousness, which rapidly progressed to intracranial hypertension and respiratory failure. Cerebrospinal fluid examination suggested purulent infection, and bacterial culture suggested Klebsiella pneumoniae, which was sensitive to other commonly used antibiotics except ampicillin. Brain magnetic resonance imaging showed multiple abnormal signals in bilateral frontal, parietal and temporal lobes, right centrum semiovale, bilateral corona radiata, basal ganglia, thalamus and insula, as well as enhancement of meningeal and ependymal membrane, and swelling of brain tissue. During hospitalization, the patient developed a blood stream infection of pan-drug-resistant Klebsiella pneumoniae and was in critical condition. After aggressive treatment, the patient was cured and discharged from the hospital. After half a year follow-up, his prognosis was good and his social function was restored. The clinical data, diagnosis and treatment of the patient were reported and the literature was reviewed to provide clinical reference for the disease.

Objective:To investigate the role of adenosine diphosphate ribosylation factor 6 (Arf6) in the pathogenesis of endometriosis.Methods:Endometrial tissues were sampled from women who were hospitalized in the Affiliated Hospital of Medical School of Ningbo University and Ningbo Women and Children′s Hospital from November 2020 to May 2021 with endometriosis ( n=44, endometriosis group) and without endometriosis ( n=17, control group). The expression of Arf6 protein in the endometrial tissues was detected by western blot. Endometrial epithelial cells from both groups were primary cultured and the distribution of intracellular mitochondria was detected by immunofluorescence. The expression of Arf6 protein was down-regulated by small interference RNA (siRNA), the distribution of mitochondria in cells with decreased Arf6 protein expression was observed, and the expression of mitochondria-related proteins development and differentiation enhancing factor 1 (DDEF1, also called AMAP1), reactive oxygen species 1 (ROS1) and epithelial-mesenchymal transition (EMT)-related proteins E-cadherin, vimentin were detected. Transwell assay was used to detect the changes in the migration ability of the cells. Results:Compared with the control group, ectopic endometrial tissue of endometriosis group showed high expression of Arf6 protein (0.174±0.019 vs 0.423±0.033; t=29.630, P<0.01); and in ectopic endometrial epithelial cells, mitochondria were distributed near the edge of the cell membrane. While Arf6 expression was down-regulated by siRNA, the distribution of mitochondria in ectopic cells returned to natural, close to the control level. In addition, the expression levels of AMAP1 and ROS1 in ectopic cells after Arf6 protein knockdown were significantly decreased. Transwell assay results indicated that knockdown of Arf6 could reduce the migration ability of ectopic epithelial cells [migration cell count: (34.3±7.5) cells]; and immunofluorescence verified low expression of E-cadherin but high expression of vimentin in ectopic epithelial cells, whereas knockdown of Arf6 protein E-cadherin expression increased but vimentin expression decreased. Conclusions:High expression of Arf6 protein in ectopic endometrial epithelial cells leads to the distribution of mitochondria tending to membrane marginalization, while inducing EMT, which are involved in the mechanism of endoheterosis pathogenesis.

Cryptococcal meningitis is a central nervous system infection caused by cryptococcal invasion of meninges and (or) brain parenchyma. It is characterized by severe intracranial hypertension and brain parenchyma damage. This opportunistic infection commonly occurs among HIV infected individuals, organ transplant recipients, and other immunosuppressive situations, and otherwise immunologically normal hosts. The global burden of human immunodeficiency virus/acquired immunodeficiency syndrome has declined over the years, but cryptococcal meningitis still has a high morbidity and mortality. The risk groups, clinical presentation, imaging characteristics, diagnostic criteria and therapeutic issues were reviewed in this article.

Objective: To identify the characteristics including clinical features and pulmonary computed tomography (CT) features of heart failure and novel coronavirus pneumonia(COVID-19). Methods: This study was a retrospective study. A total of 7 patients with Heart failure and 12 patients with COVID-19 in the Second Xiangya Hospital of Central South University between December 1, 2019 and February 15, 2020 were enrolled. The baseline clinical and imaging features of the two groups were statistically analyzed. Results: There was no significant difference in age and sex between the two groups, but the incidence of epidemiological contact history, fever or respiratory symptoms in the COVID-19 group was significantly higher than that in the heart failure group (12/12 vs. 2/7, P=0.001; 12/12 vs. 4/7, P<0.001). While the proportion of cardiovascular diseases and impaired cardiac function was significantly less than that of the heart failure group(2/12 vs.7/7, P<0.001; 0/12 vs.7/7, P<0.001). For imaging features, both groups had ground-glass opacity and thickening of interlobular septum, but the ratio of central and gradient distribution was higher in patients with heart failure than that in patients with COVID-19 (4/7 vs. 1/12, P=0.04). In heart failure group, the ratio of the expansion of small pulmonary veins was also higher (3/7 vs. 0, P=0.013), and the lung lesions can be significantly improved after effective anti-heart failure treatment. Besides, there are more disease with rounded morphology in COVID-19 (9/12 vs. 2/7, P=0.048) . Conclusions More patients with COVID-19 have epidemiological history and fever or respiratory symptoms. There are significant differences in chest CT features, such as enlargement of pulmonary veins, lesions distribution and morphology between heart failure and COVID-19.

Objective:To construct and evaluate a decision tree based on biomarkers for predicting severe acute kidney injury (AKI) in critical patients.Methods:A prospectively study was conducted. Critical patients who had been admitted to the department of critical care medicine of Xiaolan Hospital of Southern Medical University from January 2017 to June 2018 were enrolled. The clinical data of the patients were recorded, and the biomarkers, including serum cystatin C (sCys C) and urinary N-acetyl-β-D-glucosaminidase (uNAG) were established immediately after admission to intensive care unit (ICU), and the end points were recorded. The test cohort was established with patient data from January to December 2017. The decision tree classification and regression tree (CART) algorithm was used, and the best cut-off values of biomarkers were used as the decision node to construct a biomarker decision tree model for predicting severe AKI. The accuracy of the decision tree model was evaluated by the overall accuracy and the receiver operating characteristic (ROC) curve. The validation cohort, established on patient data from January to June 2018, was used to further validate the accuracy and predictive ability of the decision tree.Results:In test cohort, 263 patients were enrolled, of whom 57 developed severe AKI [defined as phase 2 and 3 of Kidney Disease: Improving Global Outcomes (KDIGO) criterion]. Compared with patients without severe AKI, severe AKI patients were older [years old: 64 (49, 74) vs. 52 (41, 66)], acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score were higher [23 (19, 27) vs. 15 (11, 20)], the incidence of hypertension, diabetes and other basic diseases and sepsis were higher (64.9% vs. 40.3%, 28.1% vs. 10.7%, 63.2% vs. 29.6%), the levels of sCys C and uNAG were higher [sCys C (mg/L): 1.38 (1.12, 2.02) vs. 0.79 (0.67, 0.98), uNAG (U/mmol Cr): 5.91 (2.43, 10.68) vs. 2.72 (1.60, 3.90)], hospital mortality and 90-day mortality were higher (21.1% vs. 4.4%, 52.6% vs. 13.1%), the length of ICU stay was longer [days: 6.0 (4.0, 9.5) vs. 3.0 (1.0, 6.0)], and renal replacement therapy requirement was higher (22.8% vs. 1.9%), with statistically significant differences (all P < 0.05). ROC curve analysis showed that the areas under ROC curve (AUC) of sCys C and uNAG in predicting severe AKI were 0.857 [95% confidence interval (95% CI) was 0.809-0.897) ] and 0.735 (95% CI was 0.678-0.788), and the best cut-off values were 1.05 mg/L and 5.39 U/mmol Cr, respectively. The structure of the biomarker decision tree model constructed by biomarkers were intuitive. The overall accuracy in predicting severe AKI was 86.0%, and AUC was 0.905 (95% CI was 0.863-0.937), the sensitivity was 0.912, and the specificity was 0.796. In validation cohort of 130 patients, this decision tree yielded an excellent AUC of 0.909 (95% CI was 0.846-0.952), the sensitivity was 0.906, and the specificity was 0.816, with an overall accuracy of 81.0%. Conclusion:The decision tree model based on biomarkers for predicting severe AKI in critical patients is highly accurate, intuitive and executable, which is helpful for clinical judgment and decision.

Objective: To investigate the influence of serum creatinine (sCr) at different time-points on prognosis of critically ill patients with acute kidney injury (AKI). Methods: This study was retrospectively analyzed the clinical data of critical patients with AKI who admitted to the mixed ICU of Xiaolan Hospital of Southern Medical University during March 2015 and January 2016. According to the clinical prognosis, the patients were divided into the renal replacement therapy (RRT) group and non-renal replacement therapy (non-RRT) group, 28-day renal loss group and renal recover group, hospital death group and survival group. Serum Cr at different time-points and clinical data were collected. The receiver operating characteristic (ROC) curve and the area under curve (AUC) were used to evaluate the capability of sCr at different time-points in predicting clinical prognosis. Results: During the study, 85 AKI patients were enrolled. The in-hospital mortality was 20%, RRT rate was 15.3%, and renal lose at 28 days after ICU admission was 31.8%. The levels of sCr out of ICU (o-sCr) and the peak of sCr were significantly higher in the RRT group than the non-RRT group (P<0.01). The o-sCr and p-sCr predicted RRT during the hospital stay with a higher AUC value (0.806 vs 0.833) than b-sCr and a-sCr. The levels of b-sCr, a-sCr, o-sCr, and p-sCr were all significantly higher in the28-day renal loss group than the kidney recover group (P<0.01). The levels of o-sCr and p-sCr were significantly higher in the hospital death group than the survival group (P<0.05). The o-sCr predicted renal lose at 28 days and hospital death with the highest AUC value of 0.850 and 0.797, respectively. Conclusions It cannot be ignored to monitor dynamically the level of sCr at different time-points in critical patients with AKI, which can predict the clinical prognosis such as hospital death, RRT and renal lose at 28 days after ICU admission.

Objective To evaluate the immune effects of virus-like particles ( VLPs) assembled from the capsid protein VP1 of a recombinant norovirus ( NoV) GⅡ. 17 genotype. Methods The recombi-nant NoV GⅡ. 17 VP1 VLPs were purified, and then tested by SDS-PAGE and Western blot to analyze the purity. The size, morphology and diameter distribution of the recombinant VLPs were detected by transmis-sion electron microscopy ( TEM) and dynamic light scattering ( DLS) analyzer. The recombinant VP1 VLPs adsorbed by aluminium adjuvant were used to immunize BALB/c mice. Serum samples were collected after immunization. Specific antibody level and neutralizing antibody activity were evaluated with enzyme linked immunosorbent assay ( ELISA) and histo-blood group antigen ( HBGA)-VLP blocking test. Cross-reactivity of serum samples with GⅠ. 1 and GⅡ. 4 VP1 VLPs were detected. Moreover, cross-protection against GⅠ. 1 and GⅡ. 4 VP1 VLPs was analyzed. Results The purity of the recombinant NoV GⅡ. 17 VP1 VLP was greater than 90％ and specific bands were detected by Western blot. TEM images and DLS experiments showed that VLPs were 30-50 nm in size with good morphology and uniformity, indicating that the recombi-nant VLPs were similar to the wildtype virus. High titers of specific antibodies were detected in serum sam-ples of the immunized mice. A certain degree of cross-reactions between serum samples and VP1 VLPs of NoV GⅠ. 1 and GⅡ. 4 were observed, but no cross-protection was detected. Conclusion The recombinant GⅡ. 17 VP1 VLPs in combination with aluminum adjuvant can induce higher titers of HBGA blocking anti-bodies in mice, suggesting that it could be used as a candidate target antigen for norovirus vaccine.