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61.
Maroyi A  MT Rasethe 《Phyton》2015,84(2):288-297
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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63.
The purpose of this study was to determine the efficacy of pre-treating mature bovine oocytes with Taxol before vitrification by the open pulled Straw method (OPS). We evaluated the effects of pre-treating the oocytes with 1 microM Taxol on chromosome organization, spindle morphology, cortical granule distribution and the ability of fertilized oocytes to develop to the blastocyst stage. After calf or cow oocyte vitrification without Taxol, significantly higher proportions of spindle abnormalities in the form of abnormal spindle structures or dispersed or decondensed chromosomes were observed compared to fresh control oocytes. In contrast, when we compared calf oocytes pre-treated with Taxol before vitrification with control calf oocytes, similar percentages of oocytes showing a normal spindle morphology were observed. The percentages of oocytes with a peripheral cortical granule (CG) distribution increased when the oocytes were pretreated with Taxol and vitrified, while oocytes vitrified without Taxol pre-treatment gave rise to higher cortical distribution percentages. Cleavage and blastocyst rates were significantly lower for vitrified versus untreated oocytes, both in cow and calf oocytes. Significantly higher cleavage rates were obtained when calf and cow oocytes were vitrified with Taxol. Pre-treatment with Taxol before cow oocyte vitrification yielded significantly higher blastocyst rates. Calf oocytes, however, were unable to develop to the blastocyst stage, irrespective of previous Taxol treatment. These results indicate that the pre-treatment of oocytes with Taxol before vitrification helps to reduce the damage induced by the cryopreservation process, and potentially improves the subsequent development of vitrified bovine oocytes. Summary sentence: Pre-treatment of oocytes with Taxol before vitrification helps to reduce the damage induced by vitrification and potentially improves the development of vitrified bovine oocytes.  相似文献   
64.

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   
65.
A report on the First International Symposium of the Austrian Proteomics Platform, Seefeld, Austria, 26-29 January 2004.  相似文献   
66.
The retinoblastoma gene product, pRb, plays a crucial role in cell cycle regulation, differentiation and inhibition of oncogenic transformation. pRb and its closely related family members p107 and p130 perform exclusive and overlapping functions during mouse development. The embryonic lethality of Rb-null animals restricts the phenotypic analysis of these mice to mid-gestation embryogenesis. We employed the Cre/loxP system to study the function of Rb in adult mouse stratified epithelium. Rb(F19/F19);K14cre mice displayed hyperplasia and hyperkeratosis in the epidermis with increased proliferation and aberrant expression of differentiation markers. In vitro, pRb is essential for the maintainance of the postmitotic state of terminally differentiated keratinocytes, preventing cell cycle re-entry. However, p107 compensates for the effects of Rb loss as the phenotypic abnormalities of Rb(F19/F19);K14cre keratinocytes in vivo and in vitro become more severe with the concurrent loss of p107 alleles. p107 alone appears to be dispensable for all these phenotypic changes, as the presence of a single Rb allele in a p107-null background rescues all these alterations. Luciferase reporter experiments indicate that these phenotypic alterations might be mediated by increased E2F activity. Our findings support a model in which pRb in conjunction with p107 plays a central role in regulating epidermal homeostasis.  相似文献   
67.
Cytogenetic analysis of caprine 2- to 4-cell embryos produced in vitro   总被引:1,自引:0,他引:1  
Prepubertal goat in vitro matured/in vitro fertilised oocytes produce only a small percentage of blastocysts. The present study examines the incidence of chromosomal anomalies in 2- to 4-cell embryos in vitro produced (IVP) from prepubertal oocytes fertilised with the semen of two males. Cumulus-oocyte complexes were obtained by slicing ovaries from slaughtered prepubertal goats. Oocytes were matured in TCM199 supplemented with 20% heat inactivated Donor Bovine Serum (DBS), 10 microg/ml FSH + 10 microg/ml LH + 1 microg/ml 17beta-oestradiol for 27 h at 38.5 degrees C in 5% CO2 in air. IVM oocytes were inseminated with the sperm from two males prepared using the swim-up and heparin-capacitation procedures. At 24 h postinsemination (hpi) the oocytes were transferred to 100 microl drops of SOF medium for a further 24 h. At 17 hpi a sample of oocytes was stained with lacmoid to evaluate the nuclear stage after fertilisation. The cleavage rate was determined at 24, 36 and 48 hpi and chromosome slides were prepared according to the gradual-fixation technique and stained with Leishman. A total of 1070 2- to 4-cell embryos from prepubertal goat oocytes were studied, but it was only possible to analyse 241 cytogenetically. Of these, 40% exhibited a normal diploid chromosome complement, 59% were haploid and 1% were triploid. There were significant differences between the two males in sperm oocyte penetration and oocyte cleavage but no differences were found in chromosomal anomalies. In conclusion, the low number of embryos karyotyped and the high number of haploid embryos found in this study suggested a high incidence of abnormal fertilised embryos and deficient cytoplasmic maturation of the oocyte which inhibits sperm head decondensation.  相似文献   
68.
Forced expression of K10, a keratin normally expressed in postmitotic, terminally differentiating epidermal keratinocytes, inhibits the progression of the cell cycle in cultured cells (Paramio, J. M., Casanova, M. Ll., Segrelles, C., Mittnacht, S., Lane, E. B., and Jorcano, J. L. (1999) Mol. Cell. Biol. 19, 3086-3094). This process requires a functional retinoblastoma (pRb) gene product and is mediated by K10-induced inhibition of Akt and PKCzeta, two signaling intermediates belonging to the phosphoinositide (PI) 3-kinase signal transduction pathway (Paramio, J. M., Segrelles, C., Ruiz, S., and Jorcano, J. L. (2001) Mol. Cell. Biol. 21, 7449-7459). Extending earlier in vitro studies to the in vivo situation, this work analyzes the alterations found in transgenic mice that ectopically express K10 in the proliferative basal cells of the epidermis. Increased expression of K10 led to a hypoplastic and hyperkeratotic epidermis due to a dramatic decrease in skin keratinocyte proliferation in association with the inhibition of Akt and PKCzeta activities. The inhibition of cell proliferation and Akt and PKCzeta activities was also observed although to a minor extent in low hK10-expressing mice. These animals displayed no overt epidermal phenotype nor overexpression of K10. In these non-phenotypic mice, ectopic K10 expression also resulted in decreased skin tumorigenesis. Collectively, these data demonstrate that keratin K10 in vivo functions include the control of epithelial proliferation in skin epidermis.  相似文献   
69.
The aim of this study was to improve in vitro embryo development of prepubertal goat oocytes by studying the effect of adding cysteamine to in vitro maturation medium, glutathione (GSH) to in vitro fertilization medium and ionomycin to the sperm capacitation medium. In experiment 1, we analysed the effect of 1 mM GSH added to fertilization medium of oocytes matured with 400 microM cysteamine. The control group were oocytes without cysteamine and GSH. In experiment 2, oocytes matured and fertilized in the presence of 400 microM cysteamine and 1 mM GSH, respectively, were inseminated with spermatozoa treated with ionomycin or heparin. In experiment 1, the percentages of total and normal fertilized oocytes were significantly higher for oocytes supplemented with cysteamine and GSH (40.26% and 30.20%, respectively) than for oocytes from the control group (16.66%, and 10.61%, respectively). The percentage of total embryos obtained after 7 days of culture was significantly higher in the group supplemented with cysteamine and GSH (30.62%) than in the control group (8.09%). In experiment 2, percentages of total and normal fertilized oocytes were significantly higher for the group of spermatozoa capacitated with ionomycin (52.21% and 37.17%, respectively) than with heparin (38.62% and 28.35%, respectively). After 7 days of culture, total embryo rate was significantly higher in the group of sperm capacitated with ionomycin (44.91%) than with heparin (38.69%). However, the percentage of embryos developed to the blastocyst stage was not affected by any of the treatments studied.  相似文献   
70.
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