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51.
Documentation of use patterns of plants across national boundaries is of relevance in understanding the importance of plant resources to livelihood strategies of different ethnic groups. Plant resources have gained prominence as a natural asset through which families derive food, firewood, income, medicines and timber, enabling particularly poor communities to achieve self-sufficiency. The objective of this study was to investigate the trends in plant usage in South Africa and Zimbabwe. An ethnobotanical investigation was conducted between January 2012 and January 2013 in the Limpopo Province, South Africa and the Midlands Province, Zimbabwe. The study used questionnaire surveys and interviews with a total of 143 participants to explore plant use patterns in South Africa and Zimbabwe. A total of 98 plant species were identified, with Zimbabwe contributing 70 species and 47 species from South Africa. The uses were classified into 15 categories, major use categories were firewood, food plants, medicine and timber. Food plant was a major plant use category in Zimbabwe, contributing 55.1%, followed by medicinal plants (36.8%), firewood (35.7%) and timber (31.6%). In contrast, firewood was the major plant use category in South Africa, contributing 18.4%, followed by food plants (17.3%), medicinal (14.3%) and timber (1.0%). Comparison of the two countries demonstrated remarkable differences in plant use patterns. The results showed that rural households in Zimbabwe were more reliant on plant resources than their counterparts in South Africa. Such a trend could be attributed to a close relationship between the local people, and their natural and agricultural environment leading to a rich knowledge base on plants, plant use and related practices. This comparative analysis strengthens the firm belief that utilization of plant resources represents an important shared heritage, preserved over the centuries, which must be exploited in order to provide further new and useful body of ethnobotanical knowledge. 相似文献
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Frelin C Imbert V Bottero V Gonthier N Samraj AK Schulze-Osthoff K Auberger P Courtois G Peyron JF 《Cell death and differentiation》2008,15(1):152-160
Apoptosis is mediated by cysteine-dependent, aspartate-directed proteases of the caspase family that proteolyse strategic intracellular substrates to induce cell suicide. We describe here that engagement of apoptotic processes by Fas triggering or by staurosporine stimulation leads to the caspase-dependent inactivation of the nuclear factor kappa B (NF-kappaB) pathway after cleavage of IKK1 (IkappaB kinase 1) and NEMO (NF-kappaB essential modulator), which are needed to transduce NF-kappaB activation signals. In this study, we have analyzed in more detail, the role of NEMO cleavage, as NEMO, but not IKK1, is important for the pro-survival actions of NF-kappaB. We demonstrate that NEMO is cleaved after Asp355 to remove the last 64 C-terminal amino acids. This short form was unable to rescue NF-kappaB activation by tumor necrosis factor-alpha (TNF-alpha) when transfected in NEMO-deficient cells. Consequently, inactivation of NEMO resulted in an inhibition of the expression of antiapoptotic NF-kappaB-target genes coding for caspase inhibitors (cIAP-1, cIAP-2) or adaptors of the TNF receptor family. NEMO-deficient Jurkat cells transiently expressing a non-cleavable mutant of NEMO were less sensitive to TNF-alpha-induced apoptosis. Therefore, downmodulation of NF-kappaB activation via the proteolytic cleavage of NEMO could represent an amplification loop for apoptosis. 相似文献
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Cevasco A Urbatzka R Bottero S Massari A Pedemonte F Kloas W Mandich A 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2008,147(2):241-251
A number of man-made chemicals has been shown to mimic endogenous hormones and to induce alterations of reproductive physiology in wild populations. Of particular importance are compounds that mimic estrogens and androgens (and their antagonists), because of their central role in reproductive function. In this study, male and female adult South African clawed toads (Xenopus laevis) were exposed to ethinylestradiol (EE2), tamoxifen (TAM), methyldihydrotestosterone (MDHT) and flutamide (FLU) as (anti)estrogenic and (anti)androgenic model compounds, respectively, at a concentration of 10(-8) M, and to water from the river Lambro (LAM), a contaminated watercourse from Northern Italy. Potential disrupting effects on reproduction were studied by histological analyses of gonads. The strongest adverse effects were observed in EE2 and LAM exposed males, e.g. tubule mean diameter reduction, spermatogenic nest breakdown and interlobular wall thickening. In both groups, the occurrence of small oocytes within the seminiferous tubules was observed. In TAM and MDHT exposed females slight oocyte atresia and occurrence of spermatogenic nests were observed. In contrast to previous studies addressing the alteration of molecular biomarkers in the same experimental setup, histological analyses of gonads were very sensitive and indicated an adverse effect of water from Lambro River on reproductive physiology of X. laevis. 相似文献
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Wither J Cai YC Lim S McKenzie T Roslin N Claudio JO Cooper GS Hudson TJ Paterson AD Greenwood CM Gladman D Pope J Pineau CA Smith CD Hanly JG Peschken C Boire G;CaNIOS Investigators Fortin PR 《Arthritis research & therapy》2008,10(5):R108-13
Introduction
Systemic lupus erythematosus is a genetically complex disease. Currently, the precise allelic polymorphisms associated with this condition remain largely unidentified. In part this reflects the fact that multiple genes, each having a relatively minor effect, act in concert to produce disease. Given this complexity, analysis of subclinical phenotypes may aid in the identification of susceptibility alleles. Here, we used flow cytometry to investigate whether some of the immune abnormalities that are seen in the peripheral blood lymphocyte population of lupus patients are seen in their first-degree relatives.Methods
Peripheral blood mononuclear cells were isolated from the subjects, stained with fluorochrome-conjugated monoclonal antibodies to identify various cellular subsets, and analyzed by flow cytometry.Results
We found reduced proportions of natural killer (NK)T cells among 367 first-degree relatives of lupus patients as compared with 102 control individuals. There were also slightly increased proportions of memory B and T cells, suggesting increased chronic low-grade activation of the immune system in first-degree relatives. However, only the deficiency of NKT cells was associated with a positive anti-nuclear antibody test and clinical autoimmune disease in family members. There was a significant association between mean parental, sibling, and proband values for the proportion of NKT cells, suggesting that this is a heritable trait.Conclusions
The findings suggest that analysis of cellular phenotypes may enhance the ability to detect subclinical lupus and that genetically determined altered immunoregulation by NKT cells predisposes first-degree relatives of lupus patients to the development of autoimmunity. 相似文献56.
Sivakumar R Sharma-Walia N Raghu H Veettil MV Sadagopan S Bottero V Varga L Levine R Chandran B 《Journal of virology》2008,82(4):1759-1776
Kaposi's sarcoma (KS), a vascular tumor associated with human immunodeficiency virus type 1 infection, is characterized by spindle-shaped endothelial cells, inflammatory cells, cytokines, growth and angiogenic factors, and angiogenesis. KS spindle cells are believed to be of the lymphatic endothelial cell (LEC) type. Kaposi's sarcoma-associated herpesvirus (KSHV, or human herpesvirus 8) is etiologically linked to KS, and in vitro KSHV infection of primary human dermal microvascular endothelial cells (HMVEC-d) is characterized by the induction of preexisting host signal cascades, sustained expression of latency-associated genes, transient expression of a limited number of lytic genes, sustained induction of NF-κB and several cytokines, and growth and angiogenic factors. KSHV induced robust vascular endothelial growth factor A (VEGF-A) and VEGF-C gene expression as early as 30 min postinfection (p.i.) in serum-starved HMVEC-d, which was sustained throughout the observation period of 72 h p.i. Significant amounts of VEGF-A and -C were also detected in the culture supernatant of infected cells. VEGF-A and -C were also induced by UV-inactivated KSHV and envelope glycoprotein gpK8.1A, thus suggesting a role for virus entry stages in the early induction of VEGF and requirement of KSHV viral gene expression for sustained induction. Exogenous addition of VEGF-A and -C increased KSHV DNA entry into target cells and moderately increased latent ORF73 and lytic ORF50 promoter activation and gene expression. KSHV infection also induced the expression of lymphatic markers Prox-1 and podoplanin as early as 8 h p.i., and a paracrine effect was seen in the neighboring uninfected cells. Similar observations were also made in the pure blood endothelial cell (BEC)-TIME cells, thus suggesting that commitment to the LEC phenotype is induced early during KSHV infection of blood endothelial cells. Treatment with VEGF-C alone also induced Prox-1 expression in the BEC-TIME cells. Collectively, these studies show that the in vitro microenvironments of KSHV-infected endothelial cells are enriched, with VEGF-A and -C molecules playing key roles in KSHV biology, such as increased infection and gene expression, as well as in angiogenesis and lymphangiogenesis, thus recapitulating the microenvironment of early KS lesions. 相似文献
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A report on the First International Symposium of the Austrian Proteomics Platform, Seefeld, Austria, 26-29 January 2004. 相似文献
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Ottavio de Cobelli Daniela Terracciano Elena Tagliabue Sara Raimondi Danilo Bottero Antonio Cioffi Barbara Jereczek-Fossa Giuseppe Petralia Giovanni Cordima Gilberto Laurino Almeida Giuseppe Lucarelli Carlo Buonerba Deliu Victor Matei Giuseppe Renne Giuseppe Di Lorenzo Matteo Ferro 《PloS one》2015,10(10)