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Janaka?WeragodaEmail author Rohini?Seneviratne Manuj?C.?Weerasinghe SM?Wijeyaratne 《BMC research notes》2016,9(1):508
Background
Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.Methods
This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.Results
The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.Conclusions
Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.3.
AP Shoko SM Limbu HA Lamtane MA Kishe-Machumu B Sekadende EE Ulotu 《African Journal of Aquatic Science》2019,44(1):15-24
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system. 相似文献
4.
Thyroid hormones (TH) stimulate oxidative metabolism in many tissues in the body, but testis is not one of them. Therefore, in this sense, testis is not considered as a target organ for TH. However, recent findings clearly show that TH have significant functions on the testis in general, and Leydig cells in particular; this begins from the onset of their differentiation through aging. Some of these functions include triggering the Leydig stem cells to differentiate, producing increased numbers of Leydig cells during differentiation by causing proliferation of Leydig stem cells and progenitors, stimulation of the Leydig cell steroidogenic function and cellular maintenance. The mechanism of action of TH on Leydig cell differentiation is still not clear and needs to be determined in future studies. However, some information on the mechanisms of TH action on Leydig cell steroidogenesis is available. TH acutely stimulate testosterone production by the Leydig cells in vitro via stimulating the production of steroidogenic acute regulatory protein (StAR) and StAR mRNA in Leydig cells; StAR is associated with intracellular trafficking of cholesterol into the mitochondria during steroid hormone synthesis. However, the presence and/or the types of TH receptors in Leydig cells and other cell types of the Leydig cell lineage is still to be resolved. Additionally, it has been shown that thyrotropin-releasing hormone (TRH), TRH receptor and TRH mRNA in the testis in many mammalian species are seen exclusively in Leydig cells. Although the significance of the latter observations are yet to be determined, these findings prompt whether hypothalamo-pituitary-thyroid axis and hypothalamo-pituitary-testis axis are short-looped through Leydig cells. 相似文献
5.
Polychlorinated biphenyls (PCBs) are worldwide pollutants and have caused hazardous effects on many animal species including humans. They have been detected in human milk and therefore exposure of newborns to PCBs is unavoidable if they are breast-fed. We present our findings on two experiments performed to test the effects of intermittent and continuous exposure of lactating rats to two different doses (80 microg and 8 microg) of Aroclor 1242 (a PCB congener) on testicular steroidogenic function of their adult male offspring. In experiment I, three groups of lactating dams received daily subcutaneous (SC) injections of either corn oil, 80 microg of Aroclor 1242 and 8 microg of Aroclor 1242 in corn oil, respectively. In experiment II, three groups of lactating dams received two SC injections per week of either corn oil or Aroclor 1242 (80 microg and 8 microg) in corn oil, respectively. Pups in all groups (n=8 per group) were weaned at day 21 and were raised on a normal diet until sacrificed at 90 days. Experiment I: Leydig cell number per testis was significantly (P<0.05) increased and the average volume of a Leydig cell was significantly (P<0.05) reduced in both groups of Aroclor-exposed rats compared to corn oil controls. Both doses of Aroclor resulted in reduced (P<0.05) serum testosterone levels compared to corn oil-treated controls. LH-stimulated testosterone production per testis and per Leydig cell was lower in Aroclor-exposed rats compared to controls. Experiment II: No changes were observed in Leydig cell size and number per testis among the three groups. Serum LH, testosterone and LH-stimulated testicular testosterone production in offspring rats of Aroclor-treated dams were not significantly different (P>.05) from the offspring of corn oil-treated dams. However, these parameters were lower in value in the offspring of dams treated with Aroclor 80 microg compared to the other two groups. LH-stimulated testosterone secretory capacity per Leydig cell was significantly lower in offspring of dams treated with Aroclor compared to controls. Serum T4 and T3 levels were not significantly different among the Aroclor-exposed and control rats in both experiments. These results demonstrate that continuous exposure of lactating mothers to 8 and 80 microg of Aroclor 1242 causes hypotrophy and malfunctioning of Leydig cells in the adult male offspring resulting in a hypoandrogenic status. Intermittent treatment of lactating mothers with 80 microg of Aroclor (but not with 8 microg of Aroclor) also produced malfunctioning of Leydig cells and a hypoandrogenic status in the absence of Leydig cell hypotrophy. However, the Aroclor 8 microg dose was ineffective to produce the above effects. 相似文献
6.
Effects of thyroid hormone on Leydig cell regeneration in the adult rat following ethane dimethane sulphonate treatment 总被引:5,自引:0,他引:5
We tested the effects of thyroid hormone on Leydig cell (LC) regeneration in the adult rat testis after ethane dimethyl sulphonate (EDS) treatment. Ninety-day-old, thyroid-intact (n = 96) and thyroidectomized (n = 5) male Sprague-Dawley rats were injected intraperitoneally (single injection) with EDS (75 mg/kg) to destroy LC. Thyroid-intact, EDS-treated rats were equally divided into three groups (n = 32 per group) and treated as follows: control (saline-injected), hypothyroid (provided 0.1% propyl thiouracil in drinking water), and hyperthyroid (received daily subcutaneous injections of tri-iodothyronine, 100 microg/kg). Testing was done at Days 2, 7, 14, and 21 for thyroid-intact rats and at Day 21 for thyroidectomized rats after the EDS treatment. Leydig cells were absent in control and hyperthyroid rats at Days 2, 7, and 14; in hypothyroid rats at all ages; and in thyroidectomized rats at Day 21. The LC number per testis in hyperthyroid rats was twice as those of controls at Day 21. 3beta-Hydroxysteroid dehydrogenase (LC marker) immunocytochemistry results agreed with these findings. Mesenchymal cell number per testis was similar in the three treatment groups of thyroid-intact rats on Days 2 and 7, but it was different on Days 14 and 21. The highest number was in the hypothyroid rats, and the lowest was in the hyperthyroid rats. Serum testosterone levels could be measured in control rats only on Day 21, were undetectable in hypothyroid rats at all stages, and were detected in hyperthyroid rats on Days 14 and 21. These levels in hyperthyroid rats were twofold greater than those of controls on Day 21. Serum androstenedione levels could be measured only in the hyperthyroid rats on Day 21. Testosterone and androstenedione levels in the incubation media showed similar patterns to those in serum, but with larger values. These findings indicate that hypothyroidism inhibits LC regeneration and hyperthyroidism results in accelerated differentiation of more mesenchymal cells into LC following the EDS treatment. The observations of the EDS-treated, thyroidectomized rats confirmed that the findings in hypothyroid rats were, indeed, due to the deficiency of thyroid hormone. 相似文献
7.
Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.8.
Sigrid NW Vorrink Helianthe SM Kort Thierry Troosters Jan-Willem J Lammers 《Respiratory research》2011,12(1):33
Background
Persons with Chronic Obstructive Pulmonary Disease (COPD), performing some level of regular physical activity, have a lower risk of both COPD-related hospital admissions and mortality. COPD patients of all stages seem to benefit from exercise training programs, thereby improving with respect to both exercise tolerance and symptoms of dyspnea and fatigue. Physical inactivity, which becomes more severe with increasing age, is a point of concern in healthy older adults. COPD might worsen this scenario, but it is unclear to what degree. This literature review aims to present the extent of the impact of COPD on objectively-measured daily physical activity (DPA). The focus is on the extent of the impact that COPD has on duration, intensity, and counts of DPA, as well as whether the severity of the disease has an additional influence on DPA.Results
A literature review was performed in the databases PubMed [MEDLINE], Picarta, PEDRO, ISI Web of Knowledge and Google scholar. After screening, 11 studies were identified as being relevant for comparison between COPD patients and healthy controls with respect to duration, intensity, and counts of DPA. Four more studies were found to be relevant to address the subject of the influence the severity of the disease may have on DPA. The average percentage of DPA of COPD patients vs. healthy control subjects for duration was 57%, for intensity 75%, and for activity counts 56%. Correlations of DPA and severity of the disease were low and/or not significant.Conclusions
From the results of this review, it appears that patients with COPD have a significantly reduced duration, intensity, and counts of DPA when compared to healthy control subjects. The intensity of DPA seems to be less affected by COPD than duration and counts. Judging from the results, it seems that severity of COPD is not strongly correlated with level of DPA. Future research should focus in more detail on the relation between COPD and duration, intensity, and counts of DPA, as well as the effect of disease severity on DPA, so that these relations become more understandable. 相似文献9.
Background
Microarray experiments, as well as other genomic analyses, often result in large gene sets containing up to several hundred genes. The biological significance of such sets of genes is, usually, not readily apparent. 相似文献10.
The partitioning of limited resources commonly explains how different species can coexist within the same ecological community. In this 2010 study, the diets of three coexisting freshwater fishes (Cape galaxias Galaxias zebratus, n = 27; Cape kurper Sandelia capensis, n = 60; Breede River redfin Pseudobarbus burchelli, n = 77) were characterised and compared in three headwater streams in South Africa's Cape Fold Ecoregion using gut contents and stable isotope analyses. These data were analysed to ascertain whether the three species exploit distinct trophic niches. Both approaches provided evidence that these species occupy different trophic niches, though with some overlap. However, dietary differences among sites were not consistent and were probably influenced by site-specific factors like resource availability. Pseudobarbus burchelli had a broader niche breadth at Tierkloof Stream than the other two species, but not at Waaihoek or Tierstel Streams. Our results also suggest that P. burchelli consumed a more omnivorous diet than do the other two species, whereas S. capensis occupied a higher trophic position than the other two species and consumed vertebrates. Our findings suggest that these species occupy non-equivalent feeding niches in Cape Fold Ecoregion headwater streams, and that diet partitioning might facilitate their coexistence in these systems. 相似文献