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91.
Innate immune mechanisms play a deterministic role in the rate of disease progression during acute infection in HIV infected humans and SIV infection of non-human primates. The role NK cells play in mediating such an effect has thus gained importance. One of the major sets of molecules that regulate NK cell function are the killer cell immunoglobulin-like molecules (KIR’s). Our laboratory has previously shown an association of KIR3DL alleles 13 and 14 with high plasma viral loads in a cohort of SIV-infected rhesus macaques. To gain a more detailed understanding of the role of KIR polymorphisms, our laboratory herein conducted studies of three additional KIR loci and show that select KIR3DH alleles appear to be more strongly associated with high plasma viral loads than KIR3DL alleles 13 and 14. In addition, we herein document the existence of additional new alleles for the KIR1D, KIR2DL4, and the KIR3DH loci.  相似文献   
92.
Several incidences of adverse effects on human health have been reported in many countries, due to consumption of edible oil adulterated with argemone oil (AO). The clinical manifestation of the disease is commonly referred to as epidemic dropsy. Our prior studies have shown that AO and isolated sanguinarine alkaloid (SANG) possess genotoxic and tumour initiating activity. In this study, the effect of AO/SANG was investigated on the development of tumour formation in mice using 7,12-dimethylbenz (a) anthracene (DMBA) initiated followed by tetradecanoyl phorbol acetate (TPA)-promoted skin tumour protocol. Single application of AO (300 μl) or SANG (4.5 μmol) when used during initiation phase in DMBA/TPA group did not reveal substantial difference in tumourigenic response. However, twice weekly application of AO (100 μl) or SANG (1.5 μmol) during promotion phase (25 weeks) resulted in enhanced tumourigenic response by ≥30% in DMBA/TPA treated group along with significant decrease in dermal tyrosinase (45–49%), histidase (30–32%), superoxide dismutase (53–56%), catalase (41%), GSH reductase (37–40%) and GSH-peroxidase activity (29–33%) compared to control. Furthermore, significant decrease of epidermal GSH (64–66%) content and enhanced formation of lipid peroxides (96–121%) was noticed following AO or SANG treatment during promotion phase to DMBA/TPA induced animals indicating the modified pro-oxidant status in skin. Although dermal biochemical parameters were also altered by AO or SANG when used during initiation phase in DMBA/TPA treated animals, nonetheless, the response in these parameters were relatively more when AO or SANG were used during promotion phase in DMBA/TPA treated animals. These results clearly suggest that AO and SANG have the ability to enhance the tumourigenic response, which may have relevance to its carcinogenic potential.  相似文献   
93.
Biological control using rhizosphere bacteria, Pseudomonas spp. and Serratia spp. is a prospective alternative technique to overcome plant parasitic nematodes infection. So, the current study was conducted in vitro on five egg-masses, 100 free eggs and 100 infective juveniles (IJs) of Meloidogyne incognita as well as greenhouse treatments on Luffa aegyptiaca L. to evaluate the nematicidal potential of six strains belong to Pseudomonas spp. and Serratia spp. as compared to oxamyl.Results showed that the inhibitory effect and juvenile mortality varied according to bacteria species, strains and exposure time. All the tested bacteria significantly (P ≤ 0.05) inhibited egg hatching and increased juvenile mortality in vitro. After 3 days of treatment, Pseudomonas spp. were more effective against eggs (48.31to 55.15%) and IJs (20.98 to 25.30%) than Serratia spp. (44.55 to 49.75% with eggs) and (19.06 to 21.61% with IJs), respectively. In the pot experiment, Luffa aegyptiaca L. treated with Serratia spp. and Pseudomonas spp. displayed significantly higher (P ≤ 0.05) levels of growth (as indicated by root length, fresh roots weight and fresh shoots weight) compared to control plants and significantly (P ≤ 0.05) suppressed galling (number of galls) and reproduction (as indicated by number of egg-masses on roots and number of eggs and juveniles in pot soil). Meanwhile, among the treated plants, Serratia spp. and Pseudomonas spp. gave the best results in shoot weight of pots infected by eggs of M. incognita than those infected with IJs as compared with positive control. While, oxamyl treatment gave the best results in pots infected by eggs and IJs.The lowest galling (gall index), number of eggs and juveniles in soil was observed in the treatment with mixture of Serratia spp. and Pseudomonas spp. as well as, enhanced growth of sponge gourd more than application each of them alone. Pots treated with oxamyl overwhelmed those treated with mixture of Serratia spp. and Pseudomonas spp.  相似文献   
94.
Mice have been used widely in in vivo and in vitro cardiovascular research. The availability of knockout mice provides further clues to the physiological significance of specific receptor subtypes. Adenosine A(1) receptor (A(1)AR)-knockout (A(1)KO) mice and their wild-type (A(1)WT) controls were employed in this investigation. The heart and aortic arch were carefully removed and retroinfused with enzyme solution (1 mg/ml collagenase type I, 0.5 mg/ml soybean trypsin inhibitor, 3% BSA, and 2% antibiotics) through the aortic arch. The efflux was collected at 30-, 60-, and 90-min intervals. The cells were centrifuged, and the pellets were mixed with medium [medium 199-F-12 medium with 10% FBS and 2% antibiotics (for endothelial cells) and advanced DMEM with 10% FBS, 10% mouse serum, 2% GlutaMax, and 2% antibiotics (for smooth muscle cells)] and plated. Endothelial cells were characterized by a cobblestone appearance and positive staining with acetylated LDL labeled with 1,1'-dioctadecyl-3,3,3',3-tetramethylindocarbocyanine perchlorate. Smooth muscle cells were characterized by positive staining of smooth muscle alpha-actin and smooth muscle myosin heavy chain. Homogeneity of the smooth muscle cells was approximately 91%. Western blot analysis showed expression of smoothelin in the cells from passages 3, 7, and 11 in A(1)WT and A(1)KO mice. Furthermore, the A(1)AR was characterized by Western blot analysis using an A(1)AR-specific antibody. To our knowledge, this is the first isolation and successful characterization of smooth muscle cells from the mouse coronary system.  相似文献   
95.
The study was conducted to assess the effect of heparin binding seminal plasma proteins (HBP) on freezability and in vitro fertilizing ability of buffalo cauda epididymal spermatozoa. Spermatozoal motility, viability and acrosomal integrity at prefreeze and post-thaw stages were studied. The in vitro fertilizing ability of spermatozoa was assessed by the application of two tests, i.e. bovine cervical mucus penetration test (BCMPT) and hypo-osmotic sperm swelling test (HOST). HBP isolated from buffalo seminal plasma and maintained in the laboratory were used for the study. Twelve pairs of epididymis from adult buffaloes slaughtered at the local abattoir were used for the study. The results indicated that HBP addition improved the progressive motility, BCMPT and HOST response at prefreeze level. HBP at a concentration of 40 microg/ml showed better results than HBP at a concentration of 80 microg/ml. However, subjecting the HBP treated spermatozoa to cryopreservation resulted in significant reduction of motility, viability, acrosomal integrity and response to BCMPT and HOST in the HBP treated groups when compared to those in control group. The deleterious effect of HBP was found to be concentration dependent with the higher concentration causing higher post-thaw damage.  相似文献   
96.
A study was undertaken to find out the effect of addition of oviductal proteins on sperm functions and lipid peroxidation (LPO) levels in buffaloes. Oviductal flushings were collected from apparently healthy buffalo genital tracts (nonluteal and luteal stage of estrous cycle), centrifuged (3000 rpm; 30 min), filtered (0.2 microm) and frozen at -20 degrees C. The proteins in pooled nonluteal and luteal oviductal fluid were precipitated overnight using ammonium sulphate, centrifuged (10,000 rpm; 30 min) and dialyzed (>10 kDa). After protein estimation, aliquots of samples containing 10 mg proteins were lyophilized in cryovials and stored frozen at -20 degrees C. Six pooled good quality ejaculates collected by artificial vagina method from two Murrah buffalo bulls were utilized for the study. After fresh semen analysis, each pooled ejaculate was split into three parts and extended in Tris-Egg yolk-Citrate extender (20% egg yolk: 7% glycerol), so that final dilution yielded approximately 60 million sperm cells/ml and cryopreserved in 0.5 ml French straws (30 million sperm cells per straw) in LN2 (-196 degrees C). Before freezing, the nonluteal and luteal oviductal proteins (NLOP &LOP) were incorporated at the concentration of 1mg/ml of extended semen. The equilibrated and frozen thawed (37 degrees C for 30s) semen was evaluated for motility, viability and acrosomal integrity, bovine cervical mucus penetration test and hypo-osmotic sperm swelling test. Besides these tests, LPO level was assessed in sperm and seminal plasma in equilibrated and frozen thawed semen. Results revealed that addition of oviductal proteins to semen before freezing convey beneficial effect in terms of spermatozoan motility, viability and acrosomal integrity. Nonluteal oviductal proteins favored significantly (P < 0.05) higher sperm penetration distance in cervical mucus (23.00+/-1.15 mm) than the control group (15.00+/-3.46 mm) in frozen thawed semen. Similarly, swollen sperm percentage was also significantly (P < 0.05) higher in NLOP treated group than the LOP included and control groups. In frozen thawed spermatozoa, the LPO level was significantly (P < 0.05) lower in NLOP added group than the LOP added and control group. It was inferred that incorporation of oviductal proteins in extender before freezing reduced the lipid peroxidation levels in buffalo spermatozoa during cryopreservation and thereby improved the post-thaw semen quality.  相似文献   
97.
Tricyclodecan-9-yl-xanthogenate (D609) has in vivo and in vitro antioxidant properties. D609 mimics glutathione (GSH) and has a free thiol group, which upon oxidation forms a disulfide. The resulting dixanthate is a substrate for glutathione reductase, regenerating D609. Recent studies have also shown that D609 protects brain in vivo and neuronal cultures in vitro against the potential Alzheimer's disease (AD) causative factor, Abeta(1-42)-induced oxidative stress and cytotoxicity. Mitochondria are important organelles with both pro- and antiapoptotic factor proteins. The present study was undertaken to test the hypothesis that intraperitoneal injection of D609 would provide neuroprotection against free radical-induced, mitochondria-mediated apoptosis in vitro. Brain mitochondria were isolated from gerbils 1 h post injection intraperitoneally (ip) with D609 and subsequently treated in vitro with the oxidants Fe(2+)/H(2)O(2) (hydroxyl free radicals), 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH, alkoxyl and peroxyl free radicals), and AD-relevant amyloid beta-peptide 1-42 [Abeta(1-42)]. Brain mitochondria isolated from the gerbils previously injected ip with D609 and subjected to these oxidative stress inducers, in vitro, showed significant reduction in levels of protein carbonyls, protein-bound hydroxynonenal [a lipid peroxidation product], 3-nitrotyrosine, and cytochrome c release compared to oxidant-treated brain mitochondria isolated from saline-injected gerbils. D609 treatment significantly maintains the GSH/GSSG ratio in oxidant-treated mitochondria. Increased activity of glutathione S-transferase, glutathione peroxidase, and glutathione reductase in brain isolated from D609-injected gerbils is consistent with the notion that D609 acts like GSH. These antiapoptotic findings are discussed with reference to the potential use of this brain-accessible glutathione mimetic in the treatment of oxidative stress-related neurodegenerative disorders, including AD.  相似文献   
98.
99.
The white grub, Hoplia philanthus Füessly (Coleoptera: Scarabaeidae), is a major pest of turf and ornamental plants in Belgium. Previously, the combination of lethal concentration of the entomopathogenic nematodes Heterorhabditis megidis or Steinernema glaseri with the entomopathogenic fungus Metarhizium anisopliae (strain CLO 53) caused additive or synergistic mortality to third-instar H. philanthus in the laboratory and greenhouse. In this present study, we examined this interaction under field conditions and compared a combination of a commercial formulation of Heterorhabditis bacteriophora (Nema-green®) and M. anisopliae. Controls were M. anisopliae, chlorpyrifos (Dursban 5 Granules) and H. bacteriophora. Field applications (surface or subsurface) were made against a mixed population of second/third-instar H. philanthus at a sport field and lawn infested in the province of West-Flanders. In both trials, the combination of M. anisopliae with H. bacteriophora at 5 × 1012 conidia/ha +2.5 × 109 infective juveniles/ha resulted in additive or synergistic effects, causing more than 95% grub mortality when the nematodes was applied 4 weeks after the application of fungus. However, application of nematode, chlorpyrifos or fungus alone provided 39–66%, 42–60% (surface) and 33–76%, 82–100% or 37–65%, (subsurface) control of H. philanthus. We concluded that the pathogen combinations we tested are compatible elements of integrated pest management and are likely to improve control of H. philanthus larvae and perhaps other insect pests beyond what is expected from single application of the pathogen.  相似文献   
100.
Modular design of artificial transcription factors   总被引:6,自引:0,他引:6  
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