Development and characterization of brain cell line from Trachinotus blochii and its application in virological and gene expression studies

A permanent cell line, SPB (Snubnose pompano brain) was established from Trachinotus blochii by the explant culture method. It has been sub-cultured more than 75 passages and showed optimal growth at 28°C using L-15 medium supplemented with 15% to 20% FBS. The SPB cells were cryopreserved at different passage levels for various applications. SPB cells were composed of fibroblastic and epithelial-like cells. The SPB cells were tested for mycoplasma contamination which was found to be negative. The origin of the SPB cell line from T. blochii was confirmed by amplification of the mitochondrial cytochrome oxidase I (COI) gene. The transfection efficiency of SPB cell line is 15% assessed by expression of green fluorescent protein using pEGFP-N1 plasmid. In addition, two CMV promotor plasmids pFNCPE42-DNA and pcDNAVP28 were transfected to SPB cells and it shows high expression levels of FNCP of fish nodavirus and VP28 protein of white spot syndrome virus by immunostaining. The SPB cells showed susceptibility to SJNNV and the infection was confirmed by RT-PCR, Western blot, ELISA, TCID50 and RT-qPCR. Experimental infection was carried out in T. blochii using SJNNV propagated in SPB cell line and found 100% mortality with clinical signs. The infection was confirmed by RT-PCR. The SPB cell line can be used for propagation of fish viral pathogens and production of the recombinant proteins.

Observational study on necrotizing enterocolitis in neonates born to SARS-CoV-2-positive mothers

Background

The impact of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic on expectant mother and their babies extends to many aspects of life. Necrotizing enterocolitis (NEC) has been recognized as a life-threatening gastrointestinal inflammatory process in neonates that has high rates of morbidity and mortality.

Objective

To investigate factors associated with NEC in hospitalized neonates whose mothers were SARS-CoV-2-positive and their relationship to mortality.

Method

This observational study was conducted from May 2020 to March 2021. All neonates who were hospitalized, after confirming that the mother was SARS-CoV-2-positive, were included in this study. The confirmation of positive SARS-CoV-2 was determined according to the reverse transcription-polymerase chain reaction (PCR) assay. The neonatal SARS-CoV-2 test was performed on the first day of birth. NEC was established based on a suggestive clinical presentation and abnormal abdominal radiographs.

Results

Of the 125 neonates enrolled in this study, there were 5 neonates who developed NEC and only one survived. Significant associated factors with NEC included lower birth weight (p < 0.001), lower gestational age (p < 0.001), positive SARS-CoV-2 PCR results (OR = 15.333; 95% CI = 2.074–113.381, p = 0.007), asphyxia (OR = 13.143; 95% CI = 1.411–122.443, p = 0.024), and mortality (OR = 156.000; 95% CI = 13.157–1849.623; p < 0.001). Mortality was significantly associated with lower gestational age (p = 0.025), cesarean section delivery (p = 0.025), and asphyxia (p = 0.025).

Conclusion

Significant associated factors with NEC in neonates born to SARS-CoV-2-positive mothers included positive SARS-CoV-2 PCR results, asphyxia, lower gestational age, and lower birth weight. In addition to caesarean section delivery, these factors were related to mortality in neonates in such conditions.

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There is an association between SARS-CoV-2 positive mothers and the incidence of NEC in their neonates.

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Significant associated factors with NEC in neonates born to SARS-CoV-2-positive mothers included positive SARS-CoV-2, asphyxia, lower gestational age, and lower birth weight.

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There is a link between NEC and mortality in neonates born to SARS-CoV-2-positive mothers.

Necrotizing Enterocolitis in Preterm Infants Born to Mother with COVID-19

Background: The COVID-19 pandemic has had a wide impact on both pregnant women and their babies. Necrotizing enterocolitis (NEC) is a gastrointestinal emergency in neonates with high morbidity and mortality. Objective: This study aims to investigate the incidence of NEC in preterm infants born to mothers with confirmed COVID-19. Methods: This observational study was conducted in neonatal intensive care unit at Dr. Soetomo General Academic Hospital, Surabaya, Indonesia, from May 2020 to April 2021. All preterm infants born to mothers with positive COVID-19 based on swab examination were included as study participants. PCR swab examination was performed within 48 hours after birth. The diagnosis of COVID-19 was defined as positive if the swab test result could detect the SARS-CoV-2 virus. The diagnosis of NEC was established by clinical symptoms and confirmed by abdominal radiography. Results: Out of 45 preterm infants included in this study, 6 infants experienced NEC. Factors that were significantly associated with the incidence of NEC included asphyxia and intubated mother. Positive PCR results from the infants alone did not significantly increase the risk of NEC. The combination of asphyxia and intubated mother (Odds Ratio [OR]=10.000, 95% Confidence Interval [CI]=1.056-94.677, P=0.020) and the combination of positive PCR result, asphyxia, and intubated mother (OR=2.438, 95% CI=1.673-3.551, P=0.007) were found to be significantly associated with the incidence of NEC Conclusion: Significant factors associated with the incidence of NEC in preterm infants born to mothers with COVID-19 included asphyxia and intubated mothers prior to delivery. A positive PCR result alone did not significantly increase the risk of NEC.