Clinical and epidemiological investigation of a child with asymptomatic COVID-19 infection following reoccurrence.

Objective: To investigate the case of a child infected with coronavirus disease 2019 (COVID-19) who had subsequent viral reactivation. Methods: We retrospectively analyzed the clinical manifestations, epidemiological data, laboratory and imaging examinations, treatment, and follow-up of the child. And then, we searched related literature using PubMed. Results: The 9-year-old boy was exposed to COVID-19 in Malawi and tested positive for NAT in Haikou, China. He was asymptomatic and admitted to our hospital. After six negative NATs, he was discharged from the hospital and quarantined in a hotel. His infection was reactivated again after 22 days (interval between first and last positive NATs). The cycle threshold (Ct) values of positive tests were 25 and 31, and the gene sequencing viral loads were very low. The viral strain Kenya/P2601/2020, a variant of the hCoV-19/Wuhan/IVDC-HB-01/2019 genome (GISAID accession IL: EPI_ISL_402119), was found when polymerase chain reaction enrichment was used to sequence the virus. However, people around him tested negative for COVID-19. Conclusion: First, we confirmed the reactivation of COVID-19 in a child. The risk of recurrent infection with SARS-CoV-2 was low, and the policy of strictly isolating patients carrying long-term viral ribonucleic acid should be reconsidered. The interval positivity was most likely due to incorrect sampling and/or testing methods. SGS and aB testing are recommended for children with viral reactivation. Second, SARS-CoV-2 viral reactivation cannot be ruled out. The possible mechanisms, such as prolonged infection and viral latent reactivation, need further investigation.

Silencing of AHNAK2 restricts thyroid carcinoma progression by inhibiting the Wnt/ß-catenin pathway.

AHNAK nucleoprotein 2 (AHNAK2) has been proposed to have an oncogenic role in various human cancers. However, the functional role of AHNAK2 in thyroid carcinoma (TC) progression has never been explored. In this study, quantitative real-time polymerase chain reaction and western blot were conducted to evaluate the expression of genes. The functional role of AHNAK2 was elucidated by cell count kit-8, colony-forming assay, wound-healing assay, and Transwell invasion assay. We found that AHNAK2 was highly expressed in thyroid carcinoma, and it was tightly correlated with the pathological stage in TC. The mRNA and protein levels of AHNAK2 were increased in TC cells. Silencing of AHNAK2 restricted the proliferation, metastasis, and epithelial-mesenchymal transition (EMT) of TC cells. AHNAK2 silencing inhibited the protein expression of ß-catenin and cyclin D1, and AHNAK2 overexpression had the opposite effects. Moreover, LiCl or ICG-001 exposure counteracted the effects of AHNAK2 silencing or upregulation on malignant phenotypes of TC cells. In conclusion, the knockdown of AHNAK2 restrained the proliferation, metastasis, and EMT of TC cells by inhibiting the Wnt/ß-catenin pathway, providing a new potential mechanism of AHNAK2 in understanding the oncogenesis and progression of TC.

Overexpression of serum lncRNA-ABHD11-AS1 as poor prognosis of patients with papillary thyroid carcinoma.

This paper was aimed at exploring the correlation of long non-coding RNA (lncRNA)-ABHD11 Antisense RNA1 (ABHD11-AS1) with the poor prognosis of patients with papillary thyroid carcinoma (PTC) and at investigating its effects on the survival of PTC cells. Serum was respectively collected from 64 PTC patients who were admitted to our hospital (PTC group) and from 50 healthy controls who underwent physical examinations (HC group) both from April 2011 to April 2015. The expression levels of ABHD11-AS1 in the serum were detected, and the values of it for diagnosis and prognosis (5-year follow-ups) were analyzed. The knockdown and overexpression models of ABHD11-AS1 in were constructed to explore the effects of the models on their proliferation, cycles and apoptosis. According to the data, the expression levels of serum ABHD11-AS1 in the PTC patients were remarkably higher than those in the healthy controls, and the area under the curve (AUC) for distinguishing the patients from the controls was 0.920. In the analysis of prognosis, the levels in patients with a poor prognosis were remarkably higher than those in patients with a good prognosis. According to the curves of overall survival rates (OSRs), the high levels of ABHD11-AS1 were remarkably correlated with the poor prognosis (a lower 5-year OSR). COX analysis showed that TNM staging, lymph node metastasis and ABHD11-AS1 were the independent prognostic factors of PTC patients. In the cell experiments, knocking down ABHD11-AS1 remarkably inhibited PTC cells from proliferation, arrested them in G0/G1 phase, and induced their apoptosis, negatively affecting their survival indices. Overexpressing this RNA had positive effects on the survival indices. Taken together, high levels of serum ABHD11-AS1 are related to the poor prognosis of PTC patients, and knocking down its expression can inhibit the survival of PTC cells.

Epidemiological investigation of a COVID-19 family cluster outbreak transmitted by a 3-month-old infant.

OBJECTIVE: To investigate the clinical characteristics, epidemiological characteristics, and transmissibility of coronavirus disease 2019 (COVID-19) in a family cluster outbreak transmitted by a 3-month-old confirmed positive infant. METHODS: Field-based epidemiological methods were used to investigate cases and their close contacts. Real-time fluorescent reverse transcription polymerase chain reaction (RT-PCR) was used to detect Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for all collected specimens. Serum SARS-CoV-2 IgM and IgG antibodies were detected by Chemiluminescence and Gold immnnochromatography (GICA). RESULTS: The outbreak was a family cluster with an attack rate of 80% (4/5). The first case in this family was a 3-month-old infant. The transmission chain was confirmed from infant to adults (her father, mother and grandmother). Fecal tests for SARS-CoV-2 RNA remained positive for 37 days after the infant was discharged. The infant's grandmother was confirmed to be positive 2 days after the infant was discharged from hospital. Patients A (3-month-old female), B (patient A's father), C (patient A's grandmother), and D (patient A's mother) had positive serum IgG and negative IgM, but patients A's grandfather serum IgG and IgM were negative. CONCLUSION: SARS-CoV-2 has strong transmissibility within family settings and presence of viral RNA in stool raises concern for possible fecal-oral transmission. Hospital follow-up and close contact tracing are necessary for those diagnosed with COVID-19.

The individual and combined effects of hypoxia and high-fat diet feeding on nutrient composition and flesh quality in Nile tilapia (Oreochromis niloticus).

Hypoxia and high-fat diet (HFD) feeding are two factors commonly existing in aquaculture. However, their individual and combined effects on nutrient composition and flesh quality in fish have not been investigated. The present study evaluated the alterations of growth, nutrient composition and flesh quality in Nile tilapia (initially 7.0 ± 0.1 g and 5.6 ± 0.2 cm) fed with normal fat diet (5.95% fat) or HFD (11.8% fat) at two dissolved oxygen levels (1.1 ± 0.1 and 7.2 ± 0.1 mg/L) for 8 weeks. The results showed that hypoxia and HFD had similar effects in inducing lipid deposition, reducing flesh protein and amino acids content, pH values and water holding ability. Hypoxia had additional adverse effects in decreasing meat yield, flesh contents of n-3 PUFA and glycogen, increasing flesh fragmentation and causing liver damages. The combination of hypoxia and HFD significantly decreased feed intake, survival rate and muscle protein content, but didn't affect flesh quality-related parameters.

LncRNA PVT1 Acts as a Tumor Promoter in Thyroid Cancer and Promotes Tumor Progression by Mediating miR-423-5p-PAK3.

INTRODUCTION: Thyroid cancer (TC) is an endocrine tumor whose risk of onset has been rising, so the deep understanding of its molecular mechanism helps formulate new treatment strategies. METHODS: This paper was aimed at exploring the regulatory mechanism of long non-coding RNA (LncRNA) plasmacytoma variant translocation 1 (PVT1) in TC. The expression of PVT1, miR-423-5p and p21-activated kinase 3 (PAK3) in TC tissues and cell lines was detected by real-time PCR. PAK3 levels were detected by Western blot. Regulatory relationships between target genes and the proliferation, invasion and apoptosis of cells and genes were analyzed. RESULTS: PVT1 and PAK3 upregulated while miR-423-5p downregulated in the tissues and cell lines. PVT1 downregulation inhibited TC cells from malignantly proliferating and invading, and promoted their apoptosis. PVT1 specifically regulated miR-423-5p, and its overexpression could weaken the anti-tumor effect of this miR on TC cells. In addition, miR-423-5p directly targeted PAK3, and knocking down its expression could weaken the inhibitory effect of PAK3 downregulation on TC progression. Besides, PVT1 acted as a competitive endogenous RNA to sponge this miR and thus regulate PAK3 expression. DISCUSSION: In conclusion, PVT1 can mediate the molecular mechanism of the miR-423-5p-PAK3 axis regulatory network on regulating TC, so it is a new direction of treating the disease.

Relationship between catecholamine level and gene polymorphism of ß1 adrenergic receptor G1165C in children with EV71 infection in hand foot and mouth disease.

OBJECTIVE: To investigate the relationship between the levels of plasma adrenaline and norepinephrine and gene polymorphism of ß1 adrenergic receptor G1165C in children with enterovirus 71 (EV71) infection in hand foot and mouth disease (HFMD). METHODS: The polymerase chain reaction (PCR) was used to detect the expression of gene polymorphism of ß1 adrenergic receptor G1165C in vitro. The levels of plasma adrenaline and norepinephrine were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The plasma norepinephrine level of severe group was significantly higher than the mild group in children with EV71 infection in HFMD (P < 0.05); however, the levels of plasma adrenaline in two groups had no statistical differences (P > 0.05); There was no significant difference in the distribution of ß1 adrenergic receptor G1165C genotype and allele between EV71 infection group and healthy control group (P > 0.05). Further analysis of EV71 infection group by dividing it into mild and severe groups showed that there was no significant difference in the distribution of genotype and allele between these two groups as well (P > 0.05). There was no significant difference in the levels of epinephrine and norepinephrine in different genotypes of EV71 infection group (P > 0.05), and in the levels of plasma epinephrine and norepinephrine in the mild and severe groups (P > 0.05). CONCLUSIONS: As the disease gets worse, the plasma norepinephrine level has a rising trend in children with EV71 infection in HFMD, which is an important indicator to evaluate the progress of the disease. However, the gene polymorphism of ß1 adrenergic receptor G1165C have no significant correlation, not only with the susceptibility and severity of EV71 infection in hand, foot and mouth disease, but also with the levels of catecholamine.