267 research outputs found
High-Risk Human Papillomaviruses and Epstein-Barr Virus in Colorectal Cancer and Their Association with Clinicopathological Status.
Colorectal cancer (CRC) is a common malignancy with a high mortality rate worldwide. It is a complex, multifactorial disease that is strongly impacted by both hereditary and environmental factors. The role of microbes (e.g., viruses) in the pathogenesis of CRC is poorly understood. In the current study, we explored the status of high-risk human papillomaviruses (HPV) and Epstein-Barr virus (EBV) in a well-defined CRC cohort using immunohistochemistry and polymerase chain reaction assays. Our data showed that high-risk HPVs were common (~80%) and EBV had a low presence (14-25%) in the CRC samples. The most common high-risk HPVs are HPV16, 31, 18, 51, 52 and 45 genotypes. The co-presence of high-risk HPV and EBV was observed in ~16% of the sample population without any significant association with the clinicopathological variables. We conclude that high-risk HPVs are very prevalent in CRC samples while EBV positivity is relatively low. The co-expression of the two viruses was observed in a minority of cases and without any correlation with the studied parameters. Further studies are necessary to confirm the clinical relevance and potential therapeutic (preventive) effects of the observations reported herein.Qatar University grants: QUHI-CMED-19/20-1 and GCC#2017-002 Q
Malaria: how useful are clinical criteria for improving the diagnosis in a highly endemic area?
To assess the validity of clinical criteria, we investigated 2096 outpatients diagnosed as malaria cases by nurses at a rural health subcentre in a highly endemic area of Papua New Guinea. 73% of the children < 10 years old had a positive blood slide for any species of Plasmodium and 32% had ⩾ 10 000 P. falciparum parasites per μL. For adults the frequencies were 51% and 9%, respectively. Stepwise logistic regression identified spleen size, no cough, temperature, no chest indrawing, and normal stools as significant predictors for a positive blood slide in children; no cough and normal stools predicted a positive blood slide in adults. Fever, no cough, vomiting, and enlarged spleen were significant predictors for a P. falciparum parasitaemia ⩾ 10 000/μL in children; in adults the only predictor was vomiting. In children the association of no cough and enlarged spleen had the best predictive value for a positive blood slide, and a temperature ⩾ 38 °C had the best predictive value for a P. falciparum parasitaemia ⩾ 10 000 μL. In adults, no major symptom had a good predictive value for a positive blood slide but vomiting had the best predictive value for a P. falciparum parasitaemia ⩾ 10 000/μL. When microscopy is not available, these findings can help in areas of high endemicity to determine which patients with a history of fever are most likely to have malaria and, more importantly, for which patients another diagnosis should be strongly considere
Water-pipe smoking and serum testosterone levels in adult males in Qatar.
Water-pipe (WP) smoking is the most common method of tobacco consumption in the Middle-East and is rapidly spreading on a global scale. Although, water-pipe smoking is linked to various diseases, such as emphysema and various types of cancers, its effect on testosterone levels has yet to be investigated. This study explores the effect of water-pipe smoking on serum testosterone levels in males in Qatar. In this cross-sectional sample within a cohort study, we retrieved data for a total of 1000 male volunteers from the Qatar BioBank (QBB) project. A self-reported questionnaire was used to determine the water-pipe smoking status of participants. Moreover, participants were stratified based on the frequency of smoking. Total testosterone and sex hormone binding globulin (SHBG) were measured clinically, whereas free testosterone and bioavailable testosterone were calculated using Vermeulen's equation. Hormone values of 541 males (277 water-pipe smokers and 264 non-smokers) were compared using multiple regression analysis based on water-pipe smoking status after adjusting for confounding factors. No statistically significant difference was observed between WP smokers and non-water-pipe smokers in the likelihood of having lower or higher total testosterone, after adjustment for confounding factors. Similar results were found in free testosterone, bioavailable testosterone, and sex hormone binding globulin (all p>0.05). When compared with the reference group, both light and heavy water-pipe smokers had a similar likelihood of circulating low total testosterone levels (OR=0.83, 95% CI: 0.46-1.49; and OR=0.80, 95% CI: 0.43-1.49; respectively). Our results reveal, for the first time, that there is no significant change in total testosterone, free testosterone, bioavailable testosterone and sex hormone binding globulin in waterpipe smokers compared to non-water-pipe smokers. Therefore, we believe that further studies are needed to confirm the effect of water-pipe smoking on testosterone in different populations.This work was supported by the College of Medicine of Qatar University and grant QUST-2-CMED-2018-1 from Qatar University
Indigenous Australians and the National Disability Insurance Scheme
The National Disability Insurance Scheme (NDIS) is one of the major policy innovations of the early 21st century in Australia, representing a new way of delivering services to people with a disability and those who care for them
Influence of PST and PHF heating conditions on the swirl flow of Al+Mg+TiO2 ternary hybrid water-ethylene glycol based nanofluid with a rotating cone
Swirl flow heat exchangers are commonly used in industrial processes such as power generation, chemical processing, and refrigeration. They can be used for both heating and cooling applications and can be designed to handle a wide range of fluid flow rates and temperatures. This study investigated the influence of PST (prescribed surface temperature) and PHF (prescribed heat flux) heating conditions on the swirl flow of Al+Mg+TiO2 ternary hybrid water-ethylene glycol (50/50) based nanofluid with a heated rotating cone. The governing ordinary differential equations were derived from the partial differential equations using the proper similarity transformations. The problem was solved using the Shifted Legendre Collocation Method (SLCM), which is a powerful numerical method. The results showed that the PST heating conditions had a significant impact on the flow and heat transfer characteristics of the ternary hybrid nanofluid. Under PHF heating conditions, the swirl velocity distribution was leading to a noteworthy influence. The use of the Al+Mg+TiO2 ternary hybrid water-ethylene glycol based nanofluid resulted in a significant enhancement in the convective heat transfer coefficient. The SLCM method provided accurate and efficient numerical solutions for the problem, demonstrating its suitability for simulating complex fluid flow and heat transfer problems
Relationships between Plasmodium falciparum infection and morbidity in a highly endemic area
A total of 736 outpatients diagnosed as having malaria using clinical criteria at a health centre in a highly endemic area of Papua New Guinea were investigated parasitologically. Plasmodium falciparum-attributable fractions were determined using a logistic regression model to compare parasite densities in cases with those of healthy individuals in community surveys. Thirty-seven percent of presumptive cases were found to have raised P. falciparum parasitaemia. This corresponds to an average reporting rate for the population of 0·53 attributable episodes per annum. Whilst the maximum prevalence of parasitaemia in the community was in children aged 5-9 years, the maximum age-specific incidence of attributable cases at the outpatient clinic was 2 cases per annum in the 2- to 4-year-old age group. The procedure for estimating attributable fractions makes it possible to compare morbidity rates between age groups, and to examine how the relationship between morbidity risk and parasite density changes with age, without diagnosing individual episodes. The average tolerance of parasites in an age group was measured by considering the level of parasitaemia associated with a given risk of malaria-attributable morbidity. In contrast to anti-parasite immunity, tolerance of parasites declines with age since at parasite isodensity the probability of being symptomatic increases with ag
Factor structure of Urdu version of the flourishing scale
Background: A great deal of research has been carried out on the assessment of the eudaimonic perspective of psychological well-being and the hedonic perspective of subjective well-being. The Flourishing Scale (FS) has been extensively used in research and practice, as it assesses the fundamental aspects of social psychological functioning. Nevertheless, the psychometric properties of Urdu versions of eudaimonic measures, such as the FS, have not yet been ascertained. The translation and validation of the FS in the Urdu language was not available, and hence this study was planned with the aim to validate the Urdu version of the FS.
Methods: We assessed the psychometric properties of the FS in a sample of adults aged 18 years and above in Pakistan (N = 130) using exploratory factor analysis based on principal component analysis with varimax rotation and confirmatory factor analysis.
Results: The exploratory factor analysis confirmed the unidimensional nature of the 8-item FS. We assessed that the Urdu version of the FS showed a high internal consistency reliability (α = 0.914) with a significant intraclass correlation coefficient (ICC), p < 0.001). In our study, the Kaiser–Mayer–Olkin value was 0.915 with a chi-square test value (χ2) of 637.687, and Bartlett's test of sphericity was significant (df = 28, p < 0.001). The intraclass correlation coefficients (ICCs) at test–retest for all domains were statistically significant (p < 0.001) and showed excellent agreement for all the items. The revised confirmatory factor analysis revealed a good-fit model, but with item 8—“People respect me”—removed due to its lower factor loading.
Conclusions: The findings suggest that the FS is a psychometrically sound instrument for assessing social psychological functioning among adults in Pakistan. Therefore, the validated Urdu version of the FS may be used in future studies of well-being in clinical psychology and positive psychology
CR1 Knops blood group alleles are not associated with severe malaria in the Gambia
The Knops blood group antigen erythrocyte polymorphisms have been associated with reduced falciparum malaria-based in vitro rosette formation (putative malaria virulence factor). Having previously identified single-nucleotide polymorphisms (SNPs) in the human complement receptor 1 (CR1/CD35) gene underlying the Knops antithetical antigens Sl1/Sl2 and McC(a)/McC(b), we have now performed genotype comparisons to test associations between these two molecular variants and severe malaria in West African children living in the Gambia. While SNPs associated with Sl:2 and McC(b+) were equally distributed among malaria-infected children with severe malaria and control children not infected with malaria parasites, high allele frequencies for Sl 2 (0.800, 1,365/1,706) and McC(b) (0.385, 658/1706) were observed. Further, when compared to the Sl 1/McC(a) allele observed in all populations, the African Sl 2/McC(b) allele appears to have evolved as a result of positive selection (modified Nei-Gojobori test Ka-Ks/s.e.=1.77, P-value <0.05). Given the role of CR1 in host defense, our findings suggest that Sl 2 and McC(b) have arisen to confer a selective advantage against infectious disease that, in view of these case-control study data, was not solely Plasmodium falciparum malaria. Factors underlying the lack of association between Sl 2 and McC(b) with severe malaria may involve variation in CR1 expression levels
IgG antibody responses to Plasmodium falciparum merozoite antigens in Kenyan children have a short half-life
BACKGROUND: Data suggest that antibody responses to malaria parasites merozoite antigens are generally short-lived and this has implications for serological studies and malaria vaccine designs. However, precise data on the kinetics of these responses is lacking. METHODS: IgG1 and IgG3 responses to five recombinant Plasmodium falciparum merozoite antigens (MSP-119, MSP-2 type A and B, AMA-1 ectodomain and EBA-175 region II) among Kenyan children were monitored using ELISA for 12 weeks after an acute episode of malaria and their half-lives estimated using an exponential decay model. RESULTS: The responses peaked mainly at week 1 and then decayed rapidly to very low levels within 6 weeks. Estimation of the half-lives of 40 IgG1 responses yielded a mean half-life of 9.8 days (95% CI: 7.6-12.0) while for 16 IgG3 responses it was 6.1 days (95% CI: 3.7-8.4), periods that are shorter than those normally described for the catabolic half-life of these antibody subclasses. CONCLUSION: This study indicates antibodies against merozoite antigens have very short half-lives and this has to be taken into account when designing serological studies and vaccines based on the antigens
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