Risk factors of peripheral arterial disease: a case control study in Sri Lanka

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.

     

Production of St. John's wort plants under controlled environment for maximizing biomass and secondary metabolites

Summary St. John's wort (Hypericum perforatum L.) is a medicinal plant used in the treatment of neurological disorders and has been recently shown to have anticancer potential. The principle medicinal components of St. John's wort are hypericin. pseudohypericin, and hyperforin. One of the problems associated with medicinal plant preparations including St. John's wort is the extreme variability in the phytochemical content, mostly due to environmental variability, and biotic and abiotic contamination during cropping. The current study was undertaken to transplant St. John's wort plants from in vitro bioreactors in a closed controlled environment system (CCES) with CO₂ enrichment for the optimized production of biomas and phytochemicals. The growth and levels of hypericin, pseudohypericin, and hyperforin in plants grown in CCES were compared with those of the greenhouse and in vitro-grown plants. The environmental parameters in the greenhouse were found to be variable whereas in the CCES these parameters were controlled. Generally, all the growth parameters and hypericin and psendohypericin levels were significantly higher in the plants grown in the CCES. These results provide the first indication that growing St. John's wort plants, under CO₂ enrichment in a closed environment system can enhance the biomass and medicinal contents. The adaptation of this growing system may be useful for the production of optimized products of St. John's wort and other medicinal species.     

<Emphasis Type="Italic">In vitro</Emphasis> regeneration of <Emphasis Type="Italic">Echinacea purpurea</Emphasis> L.: Enhancement of somatic embryogenesis by indolebutyric acid and dark pre-incubation

Summary The embryogenic potential of different Echinacea purpurea tissues, viz. leaf, cotyledon, and root, was investigated. Maximum embryo-induction was achieved from leaf dises cultured on Murashige and Skoog medium supplemented with benzylaminopurine (5.0 μM) and indolebutyric acid (2.5 μM) where 95% of the explants responded, yielding an average of 83 embryos per explant within 4 wk of culture. Incubation of cultures in the dark for an initial period of 14 d significantly increased the frequency of somatic embryogenesis (6–8-fold in leaf explants). Exposure of the abaxial surface of leaves to the medium significantly increased the number of embryos. Transfer of somatic embryos to a medium devoid of growth regulators resulted in 80% germination within 7 d. Over 73% of the somatic embryos developed roots within 28 d of culture on a medium containing naphthaleneacetic acid (10 μM) with a maximum root number of 9.8 per plantlet. Transplanting ex vitro and acclimatization for a period of 7 d were sufficient to promote establishment of plants in the greenhouse, and more than 90% of the regenerated plants survived.     

The role of fish-poultry integration on fish growth performance,yields and economic benefits among smallholder farmers in sub-Saharan Africa,Tanzania

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.     

Effects of double ligation of Stensen's duct on the rabbit parotid gland

Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14–30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts pre-ligation to surrounding a majority of the residual duct-like structures, many of which clearly were atrophic acini. Thus, both atrophy and apoptosis made major contributions to the post-ligation reduction in gland size. Structures also occurred with both ductal and acinar markers that suggested acini differentiating into ducts. Overall, the reaction to duct ligation proceeded at a considerably slower pace in the rabbit parotid glands than has been reported for the salivary glands of the rat.     

Level of daily physical activity in individuals with COPD compared with healthy controls

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.     

GObar: A Gene Ontology based analysis and visualization tool for gene sets

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.     

Pressure gradients along whole culms and leaf sheaths, and other aspects of humidity-induced gas transport in Phragmites australis

Emergent aquatic macrophytes growing in waterlogged anaerobic sediments overlain by deep water require particularly efficient ventilating systems. In Phragmites australis (Cav.) Trin. ex Steud, pressurized gas flows, generated by humidity-induced diffusion of air into leaf sheaths, enhance oxygen transport to below-ground parts and aid in the removal of respiratory CO2 and sediment-generated CO2 and methane. Although modelling and flow measurements have pointed to the probable involvement of all leaf sheaths in the flow process and the development of pressure gradients along the whole lengths of living culm and leaf sheaths, direct measurements of pressure gradients have never been reported. The aim of this study was to search for pressure gradient development in Phragmites culms and leaf sheaths and to determine their magnitudes and distribution. In addition, dynamic (with gas flow) and static pressures (no flow condition) and their relationship to flows, leaf sheath areas, and living-to-dead culm ratios were further investigated. Dynamic pressures (DeltaPd) recorded in the pith cavities of intact (non-excised) leafy culms, pneumatically isolated from the below-ground parts and venting through an artificial bore-hole near the base, revealed a curvilinear gradient of pressure 'asymptoting' towards the tips of the culms. Similarly, DeltaPd in upper and lower parts of leaf sheaths increased with distance from the base of the culm, with values in the upper parts always being greater. Curvilinear gradients of pressure were also found along pneumatically isolated individual leaf sheaths, but radial channels linking the leaf sheath aerenchyma with the pith cavity of the culm appeared to offer little resistance to flow. In keeping with predictions, static pressure differentials (DeltaPs) achieved in intact and excised culms and single leaf sheaths on intact culms proved to be relatively independent of leaf sheath area, whereas the potential for developing convective flows (pressure-driven flows) increased with increasing leaf sheath area. As measured by the ventilating coefficient [1-(DeltaPd/(DeltaPs)] the old dead (efflux) to living (influx) culm ratio of 1:12 compared with 1:25 raised ventilating efficiency from 31% to 71%, giving flows per tall culm into the rhizome system of c. 2.8 cm3 and 6.5 cm3 min-1, respectively. It was concluded that dynamic pressure gradients probably extend along the whole length of the leafy culms and leaf sheaths of Phragmites and that all leaf sheaths and all exposed points along the leaf sheaths can contribute convective gas-flow to the rhizome system.     

Ligand-dependent differences in estrogen receptor beta-interacting proteins identified in lung adenocarcinoma cells corresponds to estrogenic responses

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.