25 research outputs found

    Brine Shrimp Toxicity Evaluation Of Some Tanzanian Plants Used Traditionally For The Treatment Of Fungal Infections

    Get PDF
    Plants which are used by traditional healers in Tanzania have been evaluated to obtain preliminary data of their toxicity using the brine shrimps test. The results indicate that 9 out of 44 plant species whose extracts were tested exhibited high toxicity with LC50 values below 20μg/ml. These include Aloe lateritia Engl. (Aloaceae) [19.1μg/ml], Cassia abbreviata Oliv. (Caesalpiniaceae) [12.7μg/ml], Croton scheffleri Pax (Euphorbiaceae) [13.7μg/ml], Hymenodactyon parvifolium Brig (Rubiaceae) [13.4μg/ml], Kigelia Africana L. (Bignoniaceae) [7.2μg/ml], and Ocimum suave Oliv. (Labiatae) [16.7μg/ml]. Twelve plants gave LC50 values between 21 and 50μg/ml, 11 plants gave LC50 values between 50 and 100 μg/ml, and 18 plants gave LC50 values greater than 100 μg/ml. Keywords: Brine shrimp test; Toxicity evaluation; Traditional antifungal plants African Journal of Traditional, Complementary and Alternative Medicines Vol. 4 (2) 2007: pp. 219-22

    Seasonal Variation in Vitamin D3 Levels Is Paralleled by Changes in the Peripheral Blood Human T Cell Compartment

    Get PDF
    It is well-recognized that vitamin D3 has immune-modulatory properties and that the variation in ultraviolet (UV) exposure affects vitamin D3 status. Here, we investigated if and to what extent seasonality of vitamin D3 levels are associated with changes in T cell numbers and phenotypes. Every three months during the course of the entire year, human PBMC and whole blood from 15 healthy subjects were sampled and analyzed using flow cytometry. We observed that elevated serum 25(OH)D3 and 1,25(OH)2D3 levels in summer were associated with a higher number of peripheral CD4+ and CD8+ T cells. In addition, an increase in naïve CD4+CD45RA+ T cells with a reciprocal drop in memory CD4+CD45RO+ T cells was observed. The increase in CD4+CD45RA+ T cell count was a result of heightened proliferative capacity rather than recent thymic emigration of T cells. The percentage of Treg dropped in summer, but not the absolute Treg numbers. Notably, in the Treg population, the levels of forkhead box protein 3 (Foxp3) expression were increased in summer. Skin, gut and lymphoid tissue homing potential was increased during summer as well, exemplified by increased CCR4, CCR6, CLA, CCR9 and CCR7 levels. Also, in summer, CD4+ and CD8+ T cells revealed a reduced capacity to produce pro-inflammatory cytokines. In conclusion, seasonal variation in vitamin D3 status in vivo throughout the year is associated with changes in the human peripheral T cell compartment and may as such explain some of the seasonal variation in immune status which has been observed previously. Given that the current observations are limited to healthy adult males, larger population-based studies would be useful to validate these findings

    High transcript levels of vitamin D receptor are correlated with higher mRNA expression of human beta defensins and IL-10 in mucosa of HIV-1-exposed seronegative individuals

    Get PDF
    RESUMEN: La vitamina D (VitD) es un inmunomodulador endógena que podría proteger de la infección por VIH-1 la reducción de la activación inmune y la inducción de la expresión de VIH-1 anti-péptidos. Para establecer una correlación entre VitD y resistencia natural a la infección VIH-1, un estudio de casos y controles utilizando sangre y mucosa muestras de 58 VIH-1 expuesto, pero seronegativos (HESN) individuos , 43 VIH-1 seropositivos (SP) y 59 no controles sanos -exposed (HCS) se llevó a cabo. La concentración VitD en el plasma se determinó por ELISA, y de ARNm de unidades relativas (RU) de VDR, IL-10 , TGF-β, TNF-α e IL-1β en las células mononucleares de sangre periférica (PBMCs), oral y genital mucosa se cuantificó por QRT-PCR. mRNA niveles de humana beta -defensin (HBD) -2 y -3 se informó anteriormente y utilizados para correlaciones. Significativamente más altos niveles de VitD se encontraron en plasma, así como mayor mRNA RU de VDR en PBMCs, y en genital mucosa de HESN en comparación con HC. Además, superior mRNA RU de TNF-α, IL-1β y IL-10 , e inferior mRNA RU de TGF-β se encontraron en PBMC de HESNs en comparación con HC. También se observó mayor IL-10 mRNA RU en genital mucosa de HESNs en comparación con HC, y los ARNm de los niveles de TNF-α en oral y genital mucosa de SPs estábamos más alta en comparación con HESNs. Por otra parte, las correlaciones positivas entre VDR y la IL-10 mRNA RU en PBMCs y genital mucosa encontrados de HESNs. Por último, HBD-2 y HBD-3 ARNm RU fueron positivamente correlacionadas con VDR mRNA expresión en forma oral mucosa de HESNs. Estos resultados sugieren que los altos niveles de VitD y su receptor están asociadas con resistencia natural a la infección por VIH-1. Sobre regulación de los anti-inflamatoria IL-10 , y la inducción de anti-VIH-1 defensinas en la mucosa podría ser parte de los mecanismos implicados en esta asociación. Sin embargo, se necesitan más estudios para definir las asociaciones causales.ABSTRACT: Vitamin D (VitD) is an endogenous immunomodulator that could protect from HIV-1 infection reducing immune activation and inducing the expression of anti-HIV-1 peptides. To establish a correlation between VitD and natural resistance to HIV-1 infection, a case-control study using blood and mucosa samples of 58 HIV-1-exposed but seronegative (HESN) individuals, 43 HIV-1 seropositives (SPs) and 59 non-exposed healthy controls (HCs) was carried out. The VitD concentration in plasma was determined by ELISA, and mRNA relative units (RU) of VDR, IL-10, TGF-β, TNF-α and IL-1β in peripheral blood mononuclear cells (PBMCs), oral and genital mucosa was quantified by qRT-PCR. mRNA levels of human beta-defensin (HBD) -2 and -3 were previously reported and used for correlations. Significantly higher levels of VitD were found in plasma as well as higher mRNA RU of VDR in PBMCs, and in genital mucosa from HESN compared to HCs. In addition, higher mRNA RU of TNF-α, IL-1β and IL-10, and lower mRNA RU of TGF-β were found in PBMC from HESNs compared to HCs. We also observed higher IL-10 mRNA RU in genital mucosa of HESNs compared to HCs, and the mRNA levels of TNF-α in oral and genital mucosa of SPs were higher compared to HESNs. Furthermore, positive correlations between VDR and IL-10 mRNA RU in PBMCs and genital mucosa of HESNs were found. Finally, HBD-2 and HBD-3 mRNA RU were positively correlated with VDR mRNA expression in oral mucosa from HESNs. These results suggest that high levels of VitD and its receptor are associated with natural resistance to HIV-1 infection. Up-regulation of the anti-inflammatory IL-10, and the induction of anti-HIV-1 defensins in mucosa might be part of the mechanisms involved in this association. However, further studies are required to define causal associations

    Vitamin D and HIV Progression among Tanzanian Adults Initiating Antiretroviral Therapy

    Get PDF
    Background: There is growing evidence of an association between low vitamin D and HIV disease progression; however, no prospective studies have been conducted among adults receiving antiretroviral therapy (ART) in sub-Saharan Africa. Methods Serum 25-hydroxyvitamin D (25(OH)D) levels were assessed at ART initiation for a randomly selected cohort of HIV-infected adults enrolled in a trial of multivitamins (not including vitamin D) in Tanzania during 2006–2010. Participants were prospectively followed at monthly clinic visits for a median of 20.6 months. CD4 T-cell measurements were obtained every 4 months. Proportional hazard models were utilized for mortality analyses while generalized estimating equations were used for CD4 T-cell counts. Results: Serum 25(OH)D was measured in 1103 adults 9.2% were classified as vitamin D deficient (30 ng/mL). After multivariate adjustment, vitamin D deficiency was significantly associated with increased mortality as compared to vitamin D sufficiency (HR: 2.00; 95% CI: 1.19–3.37; p = 0.009), whereas no significant association was found for vitamin D insufficiency (HR: 1.24; 95% CI: 0.87–1.78; p = 0.24). No effect modification by ART regimen or change in the associations over time was detected. Vitamin D status was not associated with change in CD4 T-cell count after ART initiation. Conclusions: Deficient vitamin D levels may lead to increased mortality in individuals receiving ART and this relationship does not appear to be due to impaired CD4 T-cell reconstitution. Randomized controlled trials are needed to determine the safety and efficacy of vitamin D supplementation for individuals receiving ART

    Change in Vitamin D Levels Occurs Early after Antiretroviral Therapy Initiation and Depends on Treatment Regimen in Resource-Limited Settings

    Get PDF
    STUDY BACKGROUND Vitamin D has wide-ranging effects on the immune system, and studies suggest that low serum vitamin D levels are associated with worse clinical outcomes in HIV. Recent studies have identified an interaction between antiretrovirals used to treat HIV and reduced serum vitamin D levels, but these studies have been done in North American and European populations. METHODS Using a prospective cohort study design nested in a multinational clinical trial, we examined the effect of three combination antiretroviral (cART) regimens on serum vitamin D levels in 270 cART-naïve, HIV-infected adults in nine diverse countries, (Brazil, Haiti, Peru, Thailand, India, Malawi, South Africa, Zimbabwe and the United States). We evaluated the change between baseline serum vitamin D levels and vitamin D levels 24 and 48 weeks after cART initiation. RESULTS Serum vitamin D levels decreased significantly from baseline to 24 weeks among those randomized to efavirenz/lamivudine/zidovudine (mean change: -7.94 [95% Confidence Interval (CI) -10.42, -5.54] ng/ml) and efavirenz/emtricitabine/tenofovir-DF (mean change: -6.66 [95% CI -9.40, -3.92] ng/ml) when compared to those randomized to atazanavir/emtricitabine/didanosine-EC (mean change: -2.29 [95% CI -4.83, 0.25] ng/ml). Vitamin D levels did not change significantly between week 24 and 48. Other factors that significantly affected serum vitamin D change included country (p<0.001), season (p<0.001) and baseline vitamin D level (p<0.001). CONCLUSION Efavirenz-containing cART regimens adversely affected vitamin D levels in patients from economically, geographically and racially diverse resource-limited settings. This effect was most pronounced early after cART initiation. Research is needed to define the role of Vitamin D supplementation in HIV care

    Burden, Access, and Disparities in Kidney Disease

    Get PDF
    Kidney disease is a global public health problem, affecting more than 750 million persons worldwide. The burden of kidney disease varies substantially across the world, as does its detection and treatment. In many settings, rates of kidney disease and the provision of its care are defined by socioeconomic, cultural, and political factors leading to significant disparities. World Kidney Day 2019 offers an opportunity to raise awareness of kidney disease and highlight disparities in its burden and current state of global capacity for prevention and management. Here, we highlight that many countries still lack access to basic diagnostics, a trained nephrology workforce, universal access to primary health care, and renal replacement therapies. We point to the need for strengthening basic infrastructure for kidney care services for early detection and management of acute kidney injury and chronic kidney disease across all countries and advocate for more pragmatic approaches to providing renal replacement therapies. Achieving universal health coverage worldwide by 2030 is one of the World Health Organization’s Sustainable Development Goals. Although universal health coverage may not include all elements of kidney care in all countries, understanding what is feasible and important for a country or region with a focus on reducing the burden and consequences of kidney disease would be an important step toward achieving kidney health equity
    corecore