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111.
Norepinephrine (NE) induces apoptosis in cardiac myocytes, and autocrine production of angiotensin (ANG) II is required for apoptosis of alveolar epithelial cells (AECs) (Wang R, Zagariya A, Ang E, Ibarra-Sunga O, and Uhal BD. Am J Physiol Lung Cell Mol Physiol 277: L1245--L1250, 1999; Wang R, Alam G, Zagariya A, Gidea C, Pinillos H, Lalude O, Choudhary G, and Uhal BD. J Cell Physiol 185: 253--259, 2000). On this basis, we hypothesized that NE might induce apoptosis of AECs in a manner inhibitable by ANG system antagonists. Purified NE induced apoptosis in the human A549 AEC-derived cell line or in primary cultures of rat AECs, with EC(50) values of 200 and 20 nM, respectively. Neither the alpha-agonist phenylephrine nor the beta-agonist isoproterenol could mimic NE when tested alone but when applied together could induce apoptosis with potency equal to NE. Apoptosis and net cell loss (47--59% in 40 h) in response to NE was completely abrogated by the ANG-converting enzyme inhibitor lisinopril or the ANG II receptor antagonist saralasin, each at concentrations capable of blocking Fas- or tumor necrosis factor-alpha-induced apoptosis. These data suggest that NE induces apoptosis of human and rat AECs through a mechanism involving the combination of alpha- and beta-adrenoceptor activation followed by autocrine generation of ANG II.  相似文献   
112.
[Co(NH3)5Cl]Cl2 forms neutral 1:3 complex by reaction with aromatic thiohydrazides, i.e. thiobenzhydrazide, o-hydroxythiobenzhydrazide, thiophen-2-thiohydrazide and furan-2-thiohydrazide. All these complexes are diamagnetic and have been characterized by elemental analysis and combination of spectroscopic methods. Cyclic voltammometry of the complexes shows irreversible metal centered and ligand centered electron transfer reactions. One complex, tris-o-hydroxythiobenzhydrazidocobalt(III), has been crystallized from DMSO solution to produce solvated crystals and its structure has been established by X-ray crystallography. Cobalt(III) ion is linked through three hydrazinic nitrogen and three sulfur atoms of three identical deprotonated ligand molecules in a distorted octahedral environment. Involvement of -OH group in intramolecular and intermolecular hydrogen bonding is crucial for crystal formation.  相似文献   
113.
Spontaneous shoot regeneration was observed from Agrobacterium rhizogenes-induced hairy roots of Plumbago indica when these were incubated in liquid MS medium for a period of 3 weeks under continuous light. Insertion of the rolB gene in putative transformed plants was confirmed by PCR and sequencing. Transformed plants grown for a period of 1 week on solid MS medium containing 0.5 mg l−1 6-benzyladenine and then transplanted to growth regulator-free medium showed better overall growth than control plants. Transformed plants had a higher root bio-biomass and an increased plumbagin content relative to non-transformed plants.  相似文献   
114.
There are laws which protect and prevent the teenage girls from working. But still in the developing countries like India, Bangladesh, etc. teenage girls coming from low socio-economic background work, to add to the family income. There is dearth of data regarding the ergonomic studies of the teenage girls working in the manual brick manufacturing units of the unorganized sectors in India. Therefore, a field study was conducted in about four brick manufacturing units of West Bengal, India. Their job in these fields was to carry 8-10 unbaked and sun-dried bricks (49.11 +/- 2.13 Kg) from the brick field to the kiln-top and again carry the baked bricks back from the kiln to some other corner of the brick field, under the hot sun. Thus, this study aimed at evaluating their work load and their consequent work-related health effects. Results show that 86 % of them suffered from work-related pain in different body parts and there was an increase in their physiological and psychological parameters after work. It is concluded that the frequent use of awkward postures while at work (OWAS) and performing heavy to moderate types of tasks in the field are deteriorating their health conditions.  相似文献   
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116.

Background

Malaria is a major public health problem in Cameroon. Unlike in the southern forested areas where the epidemiology of malaria has been better studied prior to the implementation of control activities, little is known about the distribution and role of anophelines in malaria transmission in the coastal areas.

Methods

A 12-month longitudinal entomological survey was conducted in Tiko, Limbe and Idenau from August 2001 to July 2002. Mosquitoes captured indoors on human volunteers were identified morphologically. Species of the Anopheles gambiae complex were identified using the polymerase chain reaction (PCR). Mosquito infectivity was detected by the enzyme-linked immunosorbent assay and PCR. Malariometric indices (plasmodic index, gametocytic index, parasite species prevalence) were determined in three age groups (<5 yrs, 5–15 yrs, >15 yrs) and followed-up once every three months.

Results

In all, 2,773 malaria vectors comprising Anopheles gambiae (78.2%), Anopheles funestus (17.4%) and Anopheles nili (7.4%) were captured. Anopheles melas was not anthropophagic. Anopheles gambiae had the highest infection rates. There were 287, 160 and 149 infective bites/person/year in Tiko, Limbe and Idenau, respectively. Anopheles gambiae accounted for 72.7%, An. funestus for 23% and An. nili for 4.3% of the transmission. The prevalence of malaria parasitaemia was 41.5% in children <5 years of age, 31.5% in those 5–15 years and 10.5% in those >15 years, and Plasmodium falciparum was the predominant parasite species.

Conclusion

Malaria transmission is perennial, rainfall dependent and An. melas does not contribute to transmission. These findings are important in the planning and implementation of malaria control activities in coastal Cameroon and West Africa.
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118.
Pyricularia oryzae Cav. reacts differently to different varieties. IB race group attacked Zenith for three consecutive years for both rabi and kharif seasons under artificial inoculation condition. Three different isolates were obtained in IB race which differed in their pathogenicity giving a constant susceptible reaction to Zenith. The difference in energy potential of three isolates of P. oryzae was tested biochemically. Total sugar, protein and protein patterns were studied following modern methods. W isolate contained maximum amount of total sugar (18.3 μg/g), total protein (23.8 μg/g albumin equivalent) and seven distinct protein bands on polyacrylamide disc electrophoretic gel which was directly correlated with maximum infection value. So it was concluded that the aggressiveness of P. oryzae depends on its energy potentiality in terms of total protein and protein patterns.  相似文献   
119.

We have previously established that RiHSPRO2, a nematode resistance protein-like homolog from wild crucifer Rorippa indica (L.) Hiern is a potent candidate to control mustard aphid Lipaphis erysimi. The present study further exploits this protein through structure prediction, biosafety assessment and transgenic study. The RiHSPRO2 protein showed an abundance of alpha helices intervened with loops in the homology-based three-dimensional model. No allergenic moiety was found in its amino acid sequence based on homology search in Protein Data Base. The secondary structure of RiHSPRO2 was unstable at temperatures above 50 °C. In vitro pepsin digestion assay revealed the protein to be digested in pepsin supplemented Simulated Gastric Fluid (SGF) within 2 minutes. The protein is proved to be biologically safe as per the FAO/WHO guidelines. An efficient Agrobacterium-mediated Brassica juncea transformation involving direct organogenesis with mean transformation frequency of 5.06?±?0.28% is reported. RiHSPRO2, under the influence of constitutive promoter CaMV35S, was transformed into susceptible B. juncea cv. B85. Southern hybridization confirmed stable integration of the transgene and Western blotting confirmed consistent expression of RiHSPRO2 in the genetically modified Brassica lines. The transgene segregated following Mendelian 3:1 ratio in the successive generation. Detached leaf aphid bioassay and in planta aphid bioassay in transgenic B. juncea lines revealed a reduction in aphid survivability by 45% and a decrease in aphid fecundity by 45.6%.

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120.
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