Umbilical cord clamping and skin-to-skin contact in deliveries from women positive for SARS-CoV-2: a prospective observational study.

OBJECTIVE: To demonstrate that delayed cord clamping (DCC) is safe in mothers with confirmed SARS-CoV-2 infection. DESIGN, SETTING AND PARTICIPANTS: Prospective observational study involving epidemiological information from 403 pregnant women with SARS-CoV-2 between 1 March and 31 May 2020. Data were collected from 70 centres that participate in the Spanish Registry of COVID-19. METHODS: Patients' information was collected from their medical chart. MAIN OUTCOMES AND MEASURES: The rate of perinatal transmission of SARS-CoV-2 and development of the infection in neonates within 14 days postpartum. RESULTS: The early cord clamping (ECC) group consisted of 231 infants (57.3%) and the DCC group consisted of 172 infants (42.7%). Five positive newborns (1.7% of total tests performed) were identified with the nasopharyngeal PCR tests performed in the first 12 hours postpartum, two from the ECC group (1.7%) and three from the DCC group (3.6%). No significant differences between groups were found regarding neonatal tests for SARS-CoV-2. No confirmed cases of vertical transmission were detected. The percentage of mothers who made skin-to-skin contact within the first 24 hours after delivery was significantly higher in the DCC group (84.3% versus 45.9%). Breastfeeding in the immediate postpartum period was also significantly higher in the DCC group (77.3% versus 50.2%). CONCLUSIONS: The results of our study show no differences in perinatal outcomes when performing ECC or DCC, and skin-to-skin contact, or breastfeeding. TWEETABLE ABSTRACT: This study demonstrates that delayed cord clamping is safe in mothers with confirmed SARS-CoV-2 infection.

Regulation of tetralin biodegradation and identification of genes essential for expression of thn operons.

The tetralin biodegradation genes of Sphingomonas macrogolitabida strain TFA are clustered in two closely linked and divergent operons. To analyze expression of both operons under different growth conditions, transcriptional and translational gene fusions of the first genes of each operon to lacZ have been constructed in plasmids unable to replicate in Sphingomonas and integrated by recombination into the genome of strain TFA. Expression analysis indicated that the transcription of both genes is induced in similar ways by the presence of tetralin. Gene expression in both operons is also subjected to overimposed catabolic repression. Two additional genes named thnR and thnY have been identified downstream of thnCA3A4 genes. ThnR is similar to LysR-type regulators, and mutational analysis indicated that ThnR is strictly required for expression of the thn operons. Unlike other LysR-type regulators, ThnR does not repress its own synthesis. In fact, ThnR activates its own expression, since thnR is cotranscribed with the thnCA3A4 genes. ThnY is similar to the ferredoxin reductase components of dioxygenase systems and shows the fer2 domain, binding a Cys4[2Fe-2S] iron sulfur center, and the FAD-binding domain, common to those reductases. However, it lacks the NAD-binding domain. Intriguingly, ThnY has a regulatory role, since it is also strictly required for expression of the thn operons. Given the similarity of ThnY to reductases and the possibility of its being present in the two redox states, it is tempting to speculate that ThnY is a regulatory component connecting expression of the thn operons to the physiological status of the cell.