Health-Related Quality of Life of Nurses Caring for Hospitalised Children and Their Families: A National Cross-Sectional Study.

PURPOSE: Health-related quality of life (HRQoL) continues to be understudied among nurses in developing countries. This study aimed to assess (1) the HRQoL of nurses in Malawi caring for hospitalised children and their families, and (2) the nurses' demographic characteristics associated with their HRQoL. DESIGN AND METHODS: The cross-sectional study was carried out at 23 hospitals in Malawi, and 203 nurses participated, resulting in a 96% response rate. The Medical Outcomes Study 36-Item Short Form Health Survey was used to collect data. The physical and mental health component scores were evaluated and compared with those in a Cyprus study as the population norm. Both univariate and multivariate analyses were performed, with the significance level set at 0.05. RESULTS: The nurses' HRQoL was moderately impaired; however, the mean scores of both the physical and the mental health components of the nurses in the Cyprus study were statistically lower than those of the Malawian nurses (t = 36.541, p < 0.001 and t = 19.477, p < 0.001, respectively). Age was independently associated with a better physical health status (ß = 29.949, p = 0.038), while female nurses were more likely to report a negative physical health status compared with male nurses (ß = -97.481, p = 0.002). CONCLUSION: The findings suggested that the Malawian nurses were affected by work-related stress, which affected their mental and physical health status. The current findings represent preliminary data, and as such further studies on the association between work-related factors and HRQoL are needed. PRACTICE IMPLICATIONS: Knowledge of HRQoL from the perspective of nurses can help healthcare organisations to develop interventions to limit the negative impacts of work-related stress on nurses caring for children.

Host-interactive genes in Amerindian Helicobacter pylori diverge from their Old World homologs and mediate inflammatory responses.

Helicobacter pylori is the dominant member of the gastric microbiota and has been associated with an increased risk of gastric cancer and peptic ulcers in adults. H. pylori populations have migrated and diverged with human populations, and health effects vary. Here, we describe the whole genome of the cag-positive strain V225d, cultured from a Venezuelan Piaroa Amerindian subject. To gain insight into the evolution and host adaptation of this bacterium, we undertook comparative H. pylori genomic analyses. A robust multiprotein phylogenetic tree reflects the major human migration out of Africa, across Europe, through Asia, and into the New World, placing Amerindian H. pylori as a particularly close sister group to East Asian H. pylori. In contrast, phylogenetic analysis of the host-interactive genes vacA and cagA shows substantial divergence of Amerindian from Old World forms and indicates new genotypes (e.g., VacA m3) involving these loci. Despite deletions in CagA EPIYA and CRPIA domains, V225d stimulates interleukin-8 secretion and the hummingbird phenotype in AGS cells. However, following a 33-week passage in the mouse stomach, these phenotypes were lost in isolate V225-RE, which had a 15-kb deletion in the cag pathogenicity island that truncated CagA and eliminated some of the type IV secretion system genes. Thus, the unusual V225d cag architecture was fully functional via conserved elements, but the natural deletion of 13 cag pathogenicity island genes and the truncation of CagA impaired the ability to induce inflammation.

Essential protein-protein interactions between Plasmodium falciparum thymidylate synthase and dihydrofolate reductase domains.

In Plasmodium falciparum, dihydrofolate reductase and thymidylate synthase activities are conferred by a single 70-kDa bifunctional polypeptide (DHFR-TS, dihydrofolate reductase-thymidylate synthase) which assembles into a functional 140-kDa homodimer. In mammals, the two enzymes are smaller distinct molecules encoded on different genes. A 27-kDa amino domain of malarial DHFR-TS is sufficient to provide DHFR activity, but the structural requirements for TS function have not been established. Although the 3'-end of DHFR-TS has high homology to TS sequences from other species, expression of this protein fragment failed to yield active TS enzyme, and it failed to complement TS(-) Escherichia coli. Unexpectedly, even partial 5'-deletion of full-length DHFR-TS gene abolished TS function on the 3'-end. Thus, it was hypothesized that the amino end of the bifunctional parasite protein plays an important role in TS function. When the 27-kDa amino domain (DHFR) was provided in trans, a previously inactive 40-kDa carboxyl-domain from malarial DHFR-TS regained its TS function. Physical characterization of the "split enzymes" revealed that the 27- and the 40-kDa fragments of DHFR-TS had reassembled into a 140-kDa hybrid complex. Thus, in malarial DHFR-TS, there are physical interactions between the DHFR domain and the TS domain, and these interactions are necessary to obtain a catalytically active TS. Interference with these essential protein-protein interactions could lead to new selective strategies to treat malaria resistant to traditional DHFR-TS inhibitors.

Chromosome 2 sequence of the human malaria parasite Plasmodium falciparum.

Chromosome 2 of Plasmodium falciparum was sequenced; this sequence contains 947,103 base pairs and encodes 210 predicted genes. In comparison with the Saccharomyces cerevisiae genome, chromosome 2 has a lower gene density, introns are more frequent, and proteins are markedly enriched in nonglobular domains. A family of surface proteins, rifins, that may play a role in antigenic variation was identified. The complete sequencing of chromosome 2 has shown that sequencing of the A+T-rich P. falciparum genome is technically feasible.