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101.
A newly-synthesized cry2Ab gene was characterized in Nicotiana tabacum, before its further transformation in cotton. Synthetic cry2Ab gene was cloned in pGreen0029 and its expression was transiently analyzed at mRNA level through agroinfiltration in tobacco. The mRNA of cry2Ab was detected after 72 h agroinfiltration through PCR using total plant RNA. This construct was then transformed into N. tabacum through Agrobacterium. Insect bioassays were conducted on detached leaves using first instar Spodoptera exigua larvae; after 96 h significant insect mortality was recorded. This newly synthesized gene was effective in controlling S. exigua first instar larvae. It can be used in combinations with other Bt genes like cry1Ac for developing resistance against major insect pests of cotton and further widening the insect control spectrum.  相似文献   
102.

Background

Plants have widely been used and documented for their therapeutic potential in many parts of the world. There are, however, few reports on the use of plants for the treatment of diseases of equines. To this end, participatory epidemiology and rapid rural appraisal techniques were used to document the plants having pharmacotherapeutic significance against different ailments of equines in selected population of Punjab, Pakistan.

Methods

A survey was conducted to interview a total of 450 respondents (150 from each of the districts of Faisalabad, Lahore and Sargodha of Pakistan) to collect information about disease recognition of the equines and their treatment on a well ? structured questionnaire. A total of 60 plants belonging to 40 families were documented. An inventory was developed depicting detailed information of plants used in treatment of different conditions of equines.

Results

The top ten species of plants used were: Allium cepa, Zingiber officinale, Vernonia anthelmintica, Capsicum annum, Brassica campestris, Trachyspermum ammi, Anethum graveolens, Picrorhiza kurroa, Azadirachta indica, and Citrullus colocynthis. Seeds were the most frequently used (n?=?16/60) parts, followed by leaves (n?=?12/60) and fruits (n?=?11/60) of plants. Based on the combination of different parts of plants used in different ratios and variation in their dose or mode of preparation led to a large number of recipes/remedies against wounds, lameness, bronchitis, colic, anorexia, dermatitis, weakness, parasitism (internal & external), fever, heat stress, urine retention, swelling, toxemia, and indigestion.

Conclusions

This study generated lot of data on phytomedicinal approach for the treatment of ailments in the equines in some selected areas. It would, therefore, be imperative to expand similar studies in other parts of Pakistan and elsewhere. Moreover, use of the documented plants may be validated employing standard scientific procedures, which may have their application in the drug discovery/development by the pharmaceutical industry.
  相似文献   
103.
The development of accurate computational models of biological processes is fundamental to computational systems biology. These models are usually represented by mathematical expressions that rely heavily on the system parameters. The measurement of these parameters is often difficult. Therefore, they are commonly estimated by fitting the predicted model to the experimental data using optimization methods. The complexity and nonlinearity of the biological processes pose a significant challenge, however, to the development of accurate and fast optimization methods. We introduce a new hybrid optimization method incorporating the Firefly Algorithm and the evolutionary operation of the Differential Evolution method. The proposed method improves solutions by neighbourhood search using evolutionary procedures. Testing our method on models for the arginine catabolism and the negative feedback loop of the p53 signalling pathway, we found that it estimated the parameters with high accuracy and within a reasonable computation time compared to well-known approaches, including Particle Swarm Optimization, Nelder-Mead, and Firefly Algorithm. We have also verified the reliability of the parameters estimated by the method using an a posteriori practical identifiability test.  相似文献   
104.
105.
Several deleterious intra-acinar phenomena are simultaneously triggered on initiating acute pancreatitis. These culminate in acinar injury or inflammatory mediator generation in vitro and parenchymal damage in vivo. Supraphysiologic caerulein is one such initiator which simultaneously activates numerous signaling pathways including non-receptor tyrosine kinases such as of the Src family. It also causes a sustained increase in cytosolic calcium- a player thought to be crucial in regulating deleterious phenomena. We have shown Src to be involved in caerulein induced actin remodeling, and caerulein induced changes in the Golgi and post-Golgi trafficking to be involved in trypsinogen activation, which initiates acinar cell injury. However, it remains unclear whether an increase in cytosolic calcium is necessary to initiate acinar injury or if injury can be initiated at basal cytosolic calcium levels by an alternate pathway. To study the interplay between tyrosine kinase signaling and calcium, we treated mouse pancreatic acinar cells with the tyrosine phosphatase inhibitor pervanadate. We studied the effect of the clinically used Src inhibitor Dasatinib (BMS-354825) on pervanadate or caerulein induced changes in Src activation, trypsinogen activation, cell injury, upstream cytosolic calcium, actin and Golgi morphology. Pervanadate, like supraphysiologic caerulein, induced Src activation, redistribution of the F-actin from its normal location in the sub-apical area to the basolateral areas, and caused antegrade fragmentation of the Golgi. These changes, like those induced by supraphysiologic caerulein, were associated with trypsinogen activation and acinar injury, all of which were prevented by Dasatinib. Interestingly, however, pervanadate did not cause an increase in cytosolic calcium, and the caerulein induced increase in cytosolic calcium was not affected by Dasatinib. These findings suggest that intra-acinar deleterious phenomena may be initiated independent of an increase in cytosolic calcium. Other players resulting in acinar injury along with the Src family of tyrosine kinases remain to be explored.  相似文献   
106.
107.
Chitin based polyurethane bio-nanocomposites (PUBNC) were prepared using chitin, Delite® HPS bentonite nanoclay enriched in montmorillonite (MMT), 4,4′-diphenylmethane diisocyanate (MDI) and polycaprolactone polyol CAPA 231 (3000 g/mol−1). The prepolymers having different concentration of Delite HPS bentonite nanoclay were extended with 2 moles of chitin. The structures of the resulted polymers were determined by FT-IR technique. The effect of nanoclay contents on mechanical properties and in vitro biocompatibility was investigated. The mechanical properties of the synthesized materials were improved with increase in the Delite HPS® bentonite nanoclay contents. Optimum mechanical properties were obtained from the PU bio-nanocomposite samples having 4% Delite HPS® bentonite nanoclay. The results revealed that the final PU bio-nanocomposite having 2% Delite HPS® bentonite nanoclay contents is ideal contenders for surgical threads with on going investigations into their in vitro biocompatibility, non-toxicity, and mechanical properties.  相似文献   
108.
Cytokinesis in mammalian cells requires actin assembly at the equatorial region. Although functions of RhoA in this process have been well established, additional mechanisms are likely involved. We have examined if Cdc42 is involved in actin assembly during cytokinesis. Depletion of Cdc42 had no apparent effects on the duration of cytokinesis, while overexpression of constitutively active Cdc42 (CACdc42) caused cytokinesis failure in normal rat kidney epithelial cells. Cells depleted of Cdc42 displayed abnormal cell morphology and caused a failure of tight accumulation of actin and RhoA at the equator. In contrast, in cells overexpressing CACdc42, actin formed abnormal bundles and RhoA was largely eliminated from the equator. Our results suggest that accurate regulation of Cdc42 activity is crucial for proper equatorial actin assembly and RhoA localization during cytokinesis. Notably, our observations also suggest that tight actin concentration is not essential for cytokinesis in adherent mammalian cells.  相似文献   
109.
With declining levels of international donor funding for financing reproductive health programmes, developing country governments and international donors are looking towards private sector strategies to expand the supply of quality reproductive health services. One of the challenges of a health franchise is to improve the quality of services provided by independent private practitioners. Private providers are more likely to abide by the quality standards set by a franchiser if they see a financial benefit resulting from franchise participation. This study was conducted to measure whether (a) there were improvements in perceived quality of care and perceived access to health facilities once these facilities became part of a franchise and (b) improvements in perceived quality and perceived access were associated with increased client loyalty to franchised clinics. Franchisees were given basic reproductive health training for seven days and services marketing training for two days. Exit interviews were conducted with male and female clients at health facilities. A pre-test measurement was taken in April 2001, prior to the start of project activities. A post-test measurement was taken in February/March 2002, about 9 months after the pre-test. Multilevel regression analysis, which takes the hierarchical structure of the data into account, was used for the analysis. After taking provider-level variation into account and controlling for client characteristics, the analyses showed significant improvements in perceived quality of care and perceived access to services. Private provider participation in a franchise network helps improve client perceptions of quality of, and access to, services. Improvements in client perceptions of quality and access contribute to increased client loyalty to franchised clinics. Once increased client loyalty translates into higher client volumes, providers are likely to see the benefits of franchise participation. In turn, this should lead to increased provider willingness to remain part of the franchise and to abide by the standards of quality set by the franchiser.  相似文献   
110.
The objective of this paper is to determine the effect of ivermectin administration on cell mediated (CMI) and humoral immunity (HI) of rabbits. CMI against dinitrochlorobenzene (DNCB) and sheep red blood cells (SRBC) in rabbits was determined by delayed-type hypersensitivity and macrophage engulfment assay (MEA), respectively; whereas, HI to Pasteurella multocida B2 vaccine and SRBC was determined by indirect haemagglutination assay (IHA) and Jerne hemolytic plaque formation assay (JHPFA), respectively. The rabbits were divided into four major groups (A through D) each subdivided into four sub-groups (1 through 4). Rabbits of group A served as vehicle control while those of groups B, C and D were treated with ivermectin at the dose rates of 200 microg/kg, 400 microg/kg and 600 microg/kg b.w., respectively. Cellular immunity was determined in sub-groups 1 and 2 through DNCB and MEA, respectively while HI was determined in sub-groups 3 and 4 through IHA and JHPFA, respectively. The skin sensitivity to DNCB at 24 and 48 h and macrophage engulfment of SRBC were highest (P>0.05) in rabbits administered with 600 microg/kg b.w. The highest geometric mean titers (14.00+/-0.31) and number of plaque forming units (1860+/-0.75) were found in rabbits that received ivermectin at a dose of 600 microg/kg b.w. followed, in order by the groups that received 400 microg/kg, 200 microg/kg b.w. and controls. Leukocyte counts were significantly higher in ivermectin-treated groups (C and D) than group A (vehicle control) and B (ivermectin at the rate of 200 microg/kg). A graded dose immune response suggested an immunopotentiating effect of ivermectin at higher doses.  相似文献   
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