448 research outputs found
Exploring cucumber extract for skin rejuvenation
This study was designed to develop a topical skin-care cream water in oil (w/o) emulsion of 3% cucumber extracts versus its vehicle (Base) as control and evaluates its effects on skin-melanin, skin erythema, skin moisture, skin sebum and transepidermal water loss (TEWL). Hydroalcohol.c cucumber (Cucumis sativus) fruit extract was entrapped in the inner aqueous phase of w/o emulsion. Base containing no extract and a formulation containing 3% concentrated extract of C. sativus was formulated. The odour was adjusted with few drops of lemon oil. Both the base and formulation were stored at different storage conditions for a period of 4 weeks to predict their stability. Different stability parameters that is: Physical stability, centrifugation and pH were monitored at different time intervals. Both the base and formulation were applied to the cheeks of 21 healthy human volunteers for a period of 4 weeks. The expected pharmaceutical stability of creams was achieved from 4 weeks in vitro study period. Odour disappeared with passage of time due to volatilization of lemon oil. The base showed insignificant (p > 0.05) effects on all skin parameters except sebum that was not significant, whereas the formulation showed statistically significant (p.0.05) effects on skin sebum secretion. TEWL and erythema was increased while skin melanin and skin hydration level was decreased by formulation. However these effects were statistically insignificant (p > 0.05). The results showed a good stability over 4 weeks of observation period of both base and formulation and the formulation has anti sebum secretion, bleaching and moisturizing effects.Key words: Cucumber extract, melanin, skin moisture, skin sebum, transepidermal water loss (TEWL)
Identification of Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infections among Healthcare Workers at Sultan Qaboos University Hospital, Oman
Objectives: This study aimed to describe the incidence and features of asymptomatic COVID-19 infections among HCWs at a tertiary hospital in Oman. Methods: This cross-sectional study was conducted between August 2020 and February 2021 among HCWs with no history of COVID-19 infection using an online questionnaire to collect sociodemographic and clinical data. COVID-19 infection was diagnosed using nasopharyngeal/throat swabs, which were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Analyses were performed using Chi-squared test, Fisher’s exact test, or univariate ordinary least squares regression, as appropriate. Results: A total of 583 HCWs participated in the study. Most were female (56.6%) and the mean age was 35 ± 8 years . Only 9.6% (95% confidence interval [CI]: 7.3–12.3%) of the HCWs were at high exposure risk as they were directly involved in the care of COVID-19-infected patients. Overall, 4.1% (95% CI: 2.7–6.1%) of the HCWs screened positive for SARS-CoV-2; of these, five (20.8%) developed symptoms within two weeks. The frequency of SARS-CoV-2 positivity among HCWs working in high, intermediate, low, and miscellaneous risk areas was 1.8% (95% CI: <0.1–9.6%), 2.6% (95% CI: <0.1–6.5%), 5.3% (95% CI: 0.3–9.3%), and 4.8% (95% CI: <0.1–69.3%), respectively. Working in high-risk areas was associated with increased compliance with various infection control strategies (P <0.001). Conclusion: There was a greater frequency of SARS-CoV-2 positivity among HCWs working in lower-risk areas, whereas HCWs who worked in high-risk areas were significantly more likely to report increased compliance with infection control strategies.
Keywords: SARS-CoV-2; COVID-19 Nucleic Acid Testing; Asymptomatic Infections; Health Personnel; Occupational Exposure; Infection Control; Real-Time Polymerase Chain Reaction; Oman
Genetic variation of male reproductive success in a laboratory population of Anopheles gambiae
<p>Abstract</p> <p>Background</p> <p>For Anopheline mosquitoes, the vectors of human malaria, genetic variation in male reproductive success can have important consequences for any control strategy based on the release of transgenic or sterile males.</p> <p>Methods</p> <p>A quantitative genetics approach was used to test whether there was a genetic component to variation in male reproductive success in a laboratory population of <it>Anopheles gambiae</it>. Swarms of full sibling brothers were mated with a fixed number of females and their reproductive success was measured as (1) proportion of ovipositing females, (2) proportion of ovipositing females that produced larvae, (3) proportion of females that produced larvae, (4) number of eggs laid per female, (5) number of larvae per ovipositing female and (6) number of larvae per female.</p> <p>Results</p> <p>The proportion of ovipositing females (trait 1) and the proportion of ovipositing females that produced larvae (trait 2) differed among full sib families, suggesting a genetic basis of mating success. In contrast, the other measures of male reproductive success showed little variation due to the full sib families, as their variation are probably mostly due to differences among females. While age at emergence and wing length of the males were also heritable, they were not associated with reproductive success. Larger females produced more eggs, but males did not prefer such partners.</p> <p>Conclusion</p> <p>The first study to quantify genetic variation for male reproductive success in <it>A. gambiae </it>found that while the initial stages of male reproduction (i.e. the proportion of ovipositing females and the proportion of ovipositing females that produced larvae) had a genetic basis, the overall reproductive success (i.e. the mean number of larvae per female) did not.</p
Comparison of male reproductive success in malaria-refractory and susceptible strains of Anopheles gambiae
<p>Abstract</p> <p>Background</p> <p>In female mosquitoes that transmit malaria, the benefits of being refractory to the <it>Plasmodium </it>parasite are balanced by the immunity costs in the absence of infection. Male mosquitoes, however, gain no advantage from being refractory to blood-transmitted parasites, so that any costs associated with an enhanced immune system in the males limit the evolution of female refractoriness and has practical implications for the release of transgenic males.</p> <p>Methods</p> <p>Aspects of the male cost of carrying <it>Plasmodium</it>-refractory genes were estimated by comparing the males' immune response and reproductive success among strains of <it>Anopheles gambiae </it>that had been selected for refractoriness or extreme susceptibility to the rodent malaria parasite, <it>Plasmodium yoelii nigeriensis</it>. The refractory males had a stronger melanization response than males from the susceptible line. Four traits were used as correlates of a male's reproductive success: the proportion of females that were inseminated by a fixed number of males in a cage within a fixed time frame, the proportion of females with motile sperm in their spermathecae, the proportion of ovipositing females, and the mean number of eggs per batch.</p> <p>Results</p> <p>Although there were significant differences among groups of males in sperm motility and oviposition success, these differences in male reproductive success were not associated with the refractory or susceptible male genotypes. Contrary to expectation, females mated to early emerging refractory males laid significantly more eggs per batch than females mated to later emerging susceptible males. Sperm motility and oviposition success were strongly correlated suggesting that variation in sperm motility influences female oviposition and ultimately male reproductive success.</p> <p>Conclusion</p> <p>An increased melanization response in male <it>A. gambiae </it>does not diminish male reproductive success under the experimental protocol used in this study. That refractory males induced ovipositing females to lay more eggs than susceptible males is an interesting result for any strategy considering the release of transgenic males. That sperm motility influences female oviposition is also important for the release of transgenic males.</p
Effect of sugar on male Anopheles gambiae mating performance, as modified by temperature, space, and body size
Male mating biology
Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings are successful. Previous failures in mosquito sterile insect technique (SIT) projects have been linked to poor knowledge of local mating behaviours or the selection of deleterious phenotypes during colonisation and long-term mass rearing. Careful selection of mating characteristics must be combined with intensive field trials to ensure phenotypic characters are not antagonistic to longevity, dispersal, or mating behaviours in released males. Success has been achieved, even when colonised vectors were less competitive, due in part to extensive field trials to ensure mating compatibility and effective dispersal. The study of male mating biology in other dipterans has improved the success of operational SIT programmes. Contributing factors include inter-sexual selection, pheromone based attraction, the ability to detect alterations in local mating behaviours, and the effects of long-term colonisation on mating competitiveness. Although great strides have been made in other SIT programmes, this knowledge may not be germane to anophelines, and this has led to a recent increase in research in this area
PET Molecular Targets and Near-Infrared Fluorescence Imaging of Atherosclerosis
PURPOSE OF REVIEW: With this review, we aim to summarize the role of positron emission tomography (PET) and near-infrared fluorescence imaging (NIRF) in the detection of atherosclerosis. RECENT FINDINGS: (18)F-FDG is an established measure of increased macrophage activity. However, due to its low specificity, new radiotracers have emerged for more specific detection of vascular inflammation and other high-risk plaque features such as microcalcification and neovascularization. Novel NIRF probes are engineered to sense endothelial damage as an early sign of plaque erosion as well as oxidized low-density lipoprotein (oxLDL) as a prime target for atherosclerosis. Integrated NIRF/OCT (optical coherence tomography) catheters enable to detect stent-associated microthrombi. Novel radiotracers can improve specificity of PET for imaging atherosclerosis. Advanced NIRF probes show promise for future application in human. Intravascular NIRF might play a prominent role in the detection of stent-induced vascular injury
Land use/land cover changes and regional climate over the Loess Plateau during 2001–2009. Part I: observational evidence
Chronic Obstructive Pulmonary Disease and Lung Cancer: Underlying Pathophysiology and New Therapeutic Modalities
Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship
Comparative transcriptomics of elasmobranchs and teleosts highlight important processes in adaptive immunity and regional endothermy
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