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Background Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) RNA was found in the intestines and feces, but its clinical significance is not completely clear. We aim to characterize the longitudinal test results of SARS‐CoV‐2 RNA in anal swabs and to explore the association with disease severity. Methods We included laboratory‐confirmed coronavirus disease 2019 (COVID‐19) patients, who were hospitalized in Guangzhou Eighth People's Hospital and excluded those who had not received anal swabs for SARS‐COV‐2 RNA testing. Epidemiological, clinical, and laboratory data were obtained. Throat swabs and anal swabs were collected periodically for SARS‐COV‐2 RNA detection. Results Two hundred and seventeen eligible patients (median aged 50 years, 50.2% were females) were analyzed. 21.2% (46/217) of the patients were detected with SARS‐CoV‐2 RNA in anal swabs. The duration of viral RNA was longer, but the viral load was lower in anal swabs than throat swabs in the early stage of the disease. During a median follow‐up of 20 days, 30 (13.8%) patients were admitted to the intensive care unit (ICU) for high‐flow nasal cannula or higher‐level oxygen support measures to correct hypoxemia. Detectable viral RNA in anal swabs (adjusted hazard ratio [aHR], 2.50; 95% confidence interval [CI], 1.20‐5.24), increased C‐reactive protein (aHR, 3.14; 95% CI, 1.35‐7.32) and lymphocytopenia (aHR, 3.12; 95% CI, 1.46‐6.67) were independently associated with ICU admission. The cumulative incidence of ICU admission was higher among patients with detectable viral RNA in anal swabs (26.3% vs 10.7%, P = .006). Conclusion Detectable SARS‐CoV‐2 RNA in the digestive tract was a potential warning indicator of severe disease., Highlights We longitudinally detected the SARS‐CoV‐2 RNA in anal swabs and throat swabs, and explored the association with disease severity of COVID‐19.21.2% of COVID‐19 patients were detectable for SARS‐CoV‐2 RNA in annal swabs. The duration of virus was longer, but the viral load was lower in anal swabs than throat swabs.Patients with detectable viral RNA in anal swabs had a 2.5‐fold higher risk of ICU admission (26.3% vs. 10.7%, P = 0.006).Detectable SARS‐CoV‐2 RNA in the digestive tract was a potential warning indicator of severe disease. Screening the virus in digestive tract, close monitoring and early intervention of patients with detectable virus are needed.

Characterizing the serologic features of asymptomatic SARS-CoV-2 infection is imperative to improve diagnostics and control of SARS-CoV-2 transmission. In this study, we evaluated the antibody profiles in 272 plasma samples collected from 59 COVID-19 patients, consisting of 18 asymptomatic patients, 33 mildly ill patients and 8 severely ill patients. We measured the IgG against five viral structural proteins, different isotypes of immunoglobulins against the Receptor Binding Domain (RBD) protein, and neutralizing antibodies. The results showed that the overall antibody response was lower in asymptomatic infections than in symptomatic infections throughout the disease course. In contrast to symptomatic patients, asymptomatic patients showed a dominant IgG-response towards the RBD protein, but not IgM and IgA. Neutralizing antibody titers had linear correlations with IgA/IgM/IgG levels against SARS-CoV-2-RBD, as well as with IgG levels against multiple SARS-CoV-2 structural proteins, especially with anti-RBD or anti-S2 IgG. In addition, the sensitivity of anti-S2-IgG is better in identifying asymptomatic infections at early time post infection compared to anti-RBD-IgG. These data suggest that asymptomatic infections elicit weaker antibody responses, and primarily induce IgG antibody responses rather than IgA or IgM antibody responses. Detection of IgG against the S2 protein could supplement nucleic acid testing to identify asymptomatic patients. This study provides an antibody detection scheme for asymptomatic infections, which may contribute to epidemic prevention and control.

Trachinotus blochii (golden pompano) is an economically important cultured marine fish that is rich in polyunsaturated fat. The fatty acid profiles of triacylglycerols and phospholipids of T. blochii tissues were analyzed. Lipid contents in tissues followed the order of viscera (28.27%) > skin (17.25%) ≈ bone (16.18%) ≈ head (15.12%) > muscle (7.38%). In triacylglycerols (TAG), saturated fatty acids (palmitic acid predominated) were preferentially esterified in the sn-2 position, and monounsaturated fatty acids (oleic acid predominated) were mainly distributed in the sn-1, 3 positions. The numbers of n-3 polyunsaturated fatty acids (PUFA) in the sn-2 position were significantly greater than those in positions 1 and 3, while the n-6 PUFA were mainly found in the sn-1, 3 positions. Muscle TAG had a higher content of EPA+DHA (3.90%) than did the other tissues. In phosphatidylethanolamines, EPA+DHA in muscle (6.76%) predominated over that in other tissues. In phosphatidylcholines, EPA+DHA in bone (6.50%) predominated. This study is a guide for the biochemical and nutritional values of the T. blochii species and can be useful for further investigation of industrial applications. PRACTICAL APPLICATION: The high proportion of sn-2-palmitic acid (greater than 50%) is close to that of breast milk and the n-3 PUFA, especially EPA and DHA have the preferential distribution in the sn-2 position of triacylglycerol. Hence, golden pompano is an excellent dietary component for human nutrition and health.

miR‑338‑3p, a recently discovered miRNA, has been shown to play important roles in tumorigenesis and metastasis in various cancers. However, the exact roles and mechanisms of miR‑338‑3p remain unknown in human ovarian epithelial carcinoma (EOC). The relationship between miR‑338‑3p expression pattern and clinicopathological features of patients with EOC were determined by real-time quantitative RT-PCR. Furthermore, the role of miR‑338‑3p and possible molecular mechanisms in EOC was investigated by several in vitro approaches and in a nude mouse model. We first showed that the expression of miR‑338‑3p was significantly downregulated in EOC tissues compared to those in adjacent normal tissues, and the value was negatively related to advanced FIGO stage, high histological grading and lymph node metastasis (P

Brain demyelination is possibly one of the main pathological factors involved in schizophrenia, and targeting on myelination may be a useful strategy for schizophrenia treatment. Quetiapine, a widely used atypical antipsychotic drug for schizophrenia treatment, has been reported to have neuroprotective effects on cerebral myelination in a demyelination animal model. The objective of the present study was to evaluate the effect and underlying neuroprotective mechanism of quetiapine on the schizophrenia-like behaviors and possible cerebral demyelination induced by MK-801, an N-methyl-D-aspartate glutamate receptor antagonist. Mice were treated with chronic quetiapine (10 mg/kg/day, intraperitoneally) for 28 days. From day 22 to 28, 1 h after the administration of quetiapine, the mice were administered MK-801 (2 mg/kg/day, subcutaneously). The positive symptom of schizophrenia was measured in a locomotor activity test on day 29, the memory was evaluated by a Y-maze test on day 30, and the sensorimotor gating deficit in mice was measured by prepulse inhibition test on day 31. After the behavioral tests, the protein expression of myelin basic protein (MBP) was measured by Western Blot, and the protein expression of brain-derived neurotrophic factor (BDNF) was measured by ELISA in the frontal cortex of mice. Our results showed quetiapine attenuated schizophrenia-like behaviors including hyperactivity, memory impairment, and sensorimotor gating deficit in the MK-801 mice. In the same time, quetiapine attenuated demyelination, concurrent with attenuated BDNF decrease in the brain of MK-801-injected mice. These results suggest that the beneficial effects of quetiapine on schizophrenia might be partly related to its neuroprotective effect on brain myelin basic protein and its upregulating neuroprotective proteins such as BDNF, and indicate that modulation of cerebral demyelination could be a novel treatment target of schizophrenia.

Epidermal growth factor (EGF) has important physiological functions that are mediated by the epidermal growth factor receptor (EGFR); however, to date, the changes in cellular behaviours and signalling properties of EGF/EGFR with aging remain unclear in the pig tissue models. Hence, the present study used porcine hepatocytes as a model to explore this issue. The study revealed the following results: 1) EGF could activate the intra-cellular signalling pathways in a time- and dose-dependent manner both in the young- and aged-pig hepatocytes, EGF induced tyrosine phosphorylation of EGFR, signal transducers and activators of transcription 3 (STAT3), protein kinase B (AKT) and extra-cellular signal-regulated kinase 1/2 (ERK1/2). Nevertheless, the EGF's signalling ability in the aged-pig hepatocytes was significantly reduced compared with that of the young-pig hepatocytes; 2) although EGF/EGFR can still be internalised into cells in a time-dependent manner with aging, the endocytic pathway differs between the young- and aged-pig hepatocytes. Furthermore, the results of the present study indicated that caveolin may play a pivotal role in the endocytosis of EGF/EGFR in the aged-pig hepatocytes, which is different from that of EGF/EGFR's endocytosis in young-pig hepatocytes; 3) It is well-known that EGFR carried out its biological effects via two signalling pathways, cytoplasmic pathway (traditional) and nuclear pathway; however, we found that the nuclear localisation of EGFR was significantly reduced in the aged-pig hepatocytes, which indicated that EGFR may lose its nuclear pathway with aging. Collectively, the present study lays the foundation for further study regarding the biological functional changes occurring in EGF/EGFR with aging.

miR‑338‑3p, a recently discovered miRNA, has been shown to play important roles in tumorigenesis and metastasis in various cancers. However, the exact roles and mechanisms of miR‑338‑3p remain unknown in human ovarian epithelial carcinoma (EOC). The relationship between miR‑338‑3p expression pattern and clinicopathological features of patients with EOC were determined by real-time quantitative RT-PCR. Furthermore, the role of miR‑338‑3p and possible molecular mechanisms in EOC was investigated by several in vitro approaches and in a nude mouse model. We first showed that the expression of miR‑338‑3p was significantly downregulated in EOC tissues compared to those in adjacent normal tissues, and the value was negatively related to advanced FIGO stage, high histological grading and lymph node metastasis (P