A Cross-Sectional Study to Assess Knowledge, Attitude, and Practices Towards COVID-19 Pandemic Amongst Pregnant Women and Healthcare Staff at a Periurban Teaching Hospital in Haryana.

OBJECTIVE: The objective is to assess knowledge, attitude, and practices towards the COVID-19 pandemic amongst pregnant women and healthcare staff at a periurban teaching hospital in Haryana, India. METHODS:  This was a single centre questionnaire-based cross-sectional analysis regarding COVID-19 which was conducted at a periurban teaching hospital in Haryana, India, amongst 300 participants which included pregnant women and healthcare staff involved in managing them. They were assessed for demographic details and KAP scores (knowledge-14 questions, attitude-9 questions, and practice-14 questions). Analysis of data was done using IBM Statistical Package for the Social Sciences (SPSS) version 25.0. RESULTS: Participants in the present study had an overall adequate mean score of knowledge (22.54 ± 5.22) and were following correct practices (mean score 23.91 ± 6.72) to prevent COVID-19. The overall correlation of knowledge and practice also shows a positive correlation (0.939, p=<0.0001). CONCLUSION: This study demonstrated that the majority of the pregnant women and healthcare workers involved in the management of pregnant women had adequate knowledge and a positive attitude towards tackling COVID-19. They were following correct practices and taking necessary steps for the prevention of the disease. They had adequate knowledge regarding vaccination for pregnant females.

Timed interactions between viral and cellular replication factors during the initiation of SV40 in vitro DNA replication.

The initiation of SV40 (simian virus 40) DNA replication requires the co-operative interactions between the viral Tag (large T-antigen), RPA (replication protein A) and Pol (DNA polymerase alpha-primase) on the template DNA. Binding interfaces mapped on these enzymes and expressed as peptides competed with the mutual interactions of the native proteins. Prevention of the genuine interactions was accomplished only prior to the primer synthesis step and blocked the assembly of a productive initiation complex. Once the complex was engaged in the synthesis of an RNA primer and its extension, the interfering effects of the peptides ceased, suggesting a stable association of the replication factors during the initiation phase. Specific antibodies were still able to disrupt preformed interactions and inhibited primer synthesis and extension activities, underlining the crucial role of specific protein-protein contacts during the entire initiation process.

Different activities of the largest subunit of replication protein A cooperate during SV40 DNA replication.

Replication protein A (RPA) is a stable heterotrimeric complex consisting of p70, p32 and p14 subunits. The protein plays a crucial role in SV40 minichromosome replication. Peptides of p70 representing interaction sites for the smaller two subunits, DNA as well as the viral initiator protein large T-antigen (Tag) and the cellular DNA polymerase alpha-primase (Pol) all interfered with the replication process indicating the importance of the different p70 activities in this process. Inhibition by the peptide disrupting protein-protein interactions was observed only during the pre-initiation stage prior to primer synthesis, suggesting the formation of a stable initiation complex between RPA, Tag and Pol at the primer end.

Effects of different doses of intraumbilical oxytocin on the third stage of labor.

OBJECTIVE: To determine the optimal dose of oxytocin to be injected intraumbilically after fetal delivery for active management of the third stage of labor. METHODS: A prospective randomized study was carried out with 125 primigravidas to compare the duration of the third stage of labor following the intraumbilical administration of 50 mL of a normal saline solution alone (in a control group), or with 10 IU, 20 IU, or 30 IU of oxytocin. The volumes of blood lost were also compared. RESULTS: Compared with the control group, the duration of the third stage of labor was significantly reduced in the 3 study groups (P<0.001), and the maximum reduction was in the group that received 30 IU of oxytocin. Blood loss and hematocrit values followed the same pattern. CONCLUSION: Administering 30 IU of oxytocin intraumbilically in 50 mL of a normal saline solution after fetal delivery is a simple, noninvasive, and effective method for active management of the third stage of labor.

Insights into the oligomeric states, conformational changes, and helicase activities of SV40 large tumor antigen.

The large T (LT) antigen encoded by SV40 virus is a multi-domain, multi-functional protein that can not only transform cells but can also function as an efficient molecular machine to unwind duplex DNA for DNA replication. Here we report our findings on the oligomeric forms, domain interactions, and ATPase and helicase activities of various LT constructs. For the LT constructs that hexamerize, only two oligomeric forms, hexameric and monomeric, were detected in the absence of ATP/ADP. However, the presence of ATP/ADP stabilizes LT in the hexameric form. The LT constructs lacking the N- and C-terminal domains, but still retaining hexamerization ability, have ATPase as well as helicase activities at a level comparable to the full-length LT, suggesting the importance of hexamerization for these activities. The domain structures and the possible interactions between different LT fragments were probed with limited protease (trypsin) digestion. Such protease digestion generated a distinct pattern in the presence and absence of ATP/ADP and Mg(2+). The most C-terminal fragment (residues 628-708, containing the host-range domain), which was thought to be completely unstructured, was somewhat trypsin-resistant despite the presence of multiple Arg and Lys, possibly due to a rather structured C terminus. Furthermore, the N- and C-terminal fragments cleaved by trypsin were associated with other parts of the molecule, suggesting the interdomain interactions for the fragments at both ends.

Partial proteolysis of simian virus 40 T antigen reveals intramolecular contacts between domains and conformation changes upon hexamer assembly.

Simian virus 40 large tumor antigen (Tag) is a multi-functional viral protein that binds specifically to SV40 origin DNA, serves as the replicative DNA helicase, and orchestrates the assembly and operation of the viral replisome. Tag associated with Mg-ATP forms hexamers and, in the presence of SV40 origin DNA, double hexamers. Limited tryptic digestion of monomeric Tag revealed three major stable structural domains. The N-terminal domain spans amino acids 1-130, the central domain comprises amino acids 131-476, and the C-terminal domain extends from amino acid 513 to amino acid 698. Co-immunoprecipitation of digestion products of monomeric Tag suggests that the N-terminal domain associates stably with sequences located in the central region of the same Tag molecule. Hexamer formation protected the tryptic cleavage sites in the exposed region between the central and C-terminal domains. Upon hexamerization, this exposed region also became less accessible to a monoclonal antibody whose epitope maps in that region. The tryptic digestion products of the soluble hexamer and the DNA-bound double hexamer were indistinguishable. A low-resolution model of the intramolecular and intermolecular interactions among Tag domains in the double hexamer is proposed.

A dominant-negative mutant of human DNA helicase B blocks the onset of chromosomal DNA replication.

A cDNA encoding a human ortholog of mouse DNA helicase B, which may play a role in DNA replication, has been cloned and expressed as a recombinant protein. The predicted human DNA helicase B (HDHB) protein contains conserved helicase motifs (superfamily 1) that are strikingly similar to those of bacterial recD and T4 dda proteins. The HDHB gene is expressed at low levels in liver, spleen, kidney, and brain and at higher levels in testis and thymus. Purified recombinant HDHB hydrolyzed ATP and dATP in the presence of single-stranded DNA, displayed robust 5'-3' DNA helicase activity, and interacted physically and functionally with DNA polymerase alpha-primase. HDHB proteins with mutations in the Walker A or B motif lacked ATPase and helicase activity but retained the ability to interact with DNA polymerase alpha-primase, suggesting that the mutants might be dominant over endogenous HDHB in human cells. When purified HDHB protein was microinjected into the nucleus of cells in early G(1), the mutant proteins inhibited DNA synthesis, whereas the wild type protein had no effect. Injection of wild type or mutant protein into cells at G(1)/S did not prevent DNA synthesis. The results suggest that HDHB function is required for S phase entry.