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61.
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms  相似文献   
62.
Plant Ecology - Volatile compounds from leaf litter of invasive alien Ageratina adenophora are known to inhibit growth of native species in sub-tropical Asia, but there is not...  相似文献   
63.
In a bid to characterize the antigens and immunization mechanisms which may be used to produce a protective response against L. donovani, role of lipid associated polysaccharide (LPS) antigen and whole antigen was evaluated. BALB/C mice were immunized with whole or LPS antigen in combination with one of three putative adjuvents (anti CD-2 antibody/FIA/0.85% Saline). LPS antigen emulsified in anti CD-2 antibody was found to induce significant antibodies in mice on day 28 against challenge with lethal dose of L. donovani. Immunoprophylactic properties of LPS and whole antigen was investigated on day 40 through cytokine elicitation (IL-2), MIF) in culture supernatants of spleen cells, but before that MHC-II expressed on macrophage was studied. The LPS antigen in combination with anti CD-2 antibody was found to be most immuno-reactive inducing higher MHC-II expression on macrophages which was associated with substantial rise in the level of MIF and IL-2. It coincided with decline in antibody titre in 100% mice immunized with LPS antigen while Leishmania injected as whole antigen failed to induce specific macrophage and T-cell response with all the above formulations. We surmise from our data that lipid associated polysaccharide antigen linked to anti CD-2 antibody has potential for eliciting protective immunity against Leishmania.  相似文献   
64.
Molecular and phylogenetic characterisation of Cryptosporidium from birds   总被引:4,自引:0,他引:4  
Avian isolates of Cryptosporidium species from different geographic locations were sequenced at two loci, the 18S rRNA gene and the heat shock gene (HSP-70). Phylogenetic analysis of the sequence data provided support for the existence of a new avian species of Cryptosporidium infecting finches and a second species infecting a black duck. The identity of Cryptosporidium baileyi and Cryptosporidium meleagridis as valid species was confirmed. Also, C. baileyi was identified in a number of isolates from the brown quail extending the host range of this species.  相似文献   
65.
Abderrazak, S. B., Oury, B, Lal, A. A., Bosseno, M.-F., Force-Barge, P., Dujardin, J.-P., Fandeur, T., Molez, J.-F., Kjellberg, F., Ayala, F. J., and Tibayrenc, M. 1999. Plasmodium falciparum: Population genetic analysis by multilocus enzyme electrophoresis and other molecular markers. Experimental Parasitology 92, 232-238. The population structure of Plasmodium falciparum, the agent of malignant malaria, is uncertain. We have analyzed multilocus enzyme electrophoresis (MLEE) polymorphisms at 7-12 gene loci in each of four populations (two populations in Burkina Faso, one in Sudan, one in Congo), plus one "cosmopolitan" sample consisting of parasite cultures from 15 distant localities in four different continents. We have also performed random amplified polymorphic DNA analysis (RAPD) and restriction fragment length polymorphism (RFLP) and characterized gene varia tion at four antigen genes in the Congo population. All genetic assays show abundant genetic variability in all populations analyzed. With the isoenzyme assays, strong linkage disequilibrium is apparent in at least two local populations, the Congo population and one population from Burkina Faso, as well as in the cosmopolitan sample, and less definitely in the other Burkina Faso population. However, no linkage disequilibrium is detected in the Congo population with the molecular assays. We failed to detect any nonrandom association between the different kinds of genetic markers; that is, MLEE with RAPD or RFLP, RAPD with RFLP, and so on. Although isoenzyme data show statistical departures from panmictic expectations, these results suggest that in the areas under survey, P. falciparum populations do not undergo predominant clonal evolution and show no clear-cut subdivisions, un like Trypanosoma cruzi, Leishmania sp., and other major parasitic species. We discuss the epidemiological and taxonomical significance of these results.  相似文献   
66.
A hydrocarbon degrading Acinetobacter baumannii S30 strain, isolated from crude oil-contaminated soil, was inserted with the lux gene from the luciferase gene cassette luxCDABE. Soil microcosms were designed to study the degradation efficacy for total petroleum hydrocarbon (TPH) of crude oil by lux-tagged A. baumannii S30 pJES. Bioaugmentation of a TPH-contaminated microcosm with A baumannii S30 pJES showed that TPH levels were reduced from 89.3 to 53.9 g/kg soil in 90 days. Biodegradation of TPH by A baumannii S30 pJES was also monitored in shake flask conditions, which showed a reduction of initial TPH levels by over 50% at the end of 120 h. A lux-PCR-based approach along with the standard dilution plating with selective antibiotics was successfully utilized to monitor the survivability of the lux-tagged strain A. baumannii S30 pJES in soil microcosms and stability of the lux insert in the host strain A. baumannii S30. The selective plating technique indicated the population of A. baumannii S30 pJES to be 6.5+/-0.13 x 10(8) CFU/g at day zero (just after bioaugmentation) and 2.09+/-0.08 x 10(8) CFU/g of soil after 90 days of incubation. lux-PCR confirmed the stability of the insert in all the randomly selected colonies of A. baumannii strains from the antibiotic plates. The lux insert was stable after 50 generations in Luria Bertini broth and storage at -70 degrees C as glycerol stocks for over a year. These results revealed that the lux insert was stable and lux-tagged A. baumannii S30 strain could survive in a TPH-contaminated soil microcosm and could degrade TPH in the soil microcosm conditions. It can be used as an effective marker to monitor the survival of augmented strains at a bioremediation site.  相似文献   
67.
Clinical application of composite tissue allograft transplants opened discussion on the restoration of facial deformities by allotransplantation. The authors introduce a hemifacial allograft transplant model to investigate the rationale for the development of functional tolerance across the major histocompatibility complex barrier. Eighteen rats in three groups were studied. The composite hemifacial allotransplantations including the ear and scalp were performed between Lewis-Brown Norway (RT1l+n) and Lewis (RT1l) rats and isotransplantations were performed between Lewis rats. Isograft controls (n = 6) and allograft controls (n = 6) did not receive treatment. Allografts in treatment group (n = 6) were treated with cyclosporine A 16 mg/kg/day during the first week; this dose was tapered to 2 mg/kg/day over 4 weeks and maintained at this level thereafter. Functional tolerance to face allografts was evaluated clinically and histologically. Donor-specific chimerism was assessed at days 21 and 63 by flow cytometry. In vitro evaluation of donor-specific tolerance was performed by mixed lymphocyte reaction at day 160 after transplantation. Isograft controls survived indefinitely. All nontreated allografts were rejected within 5 to 7 days after transplantation, as confirmed by histopathologic analysis. Five of six face allografts under the cyclosporine A protocol showed no signs of rejection for up to 240 days and remained alive and under evaluation, whereas one animal showed signs of rejection at day 140. This was reversed by adjustment of the cyclosporine A dose. At day 21 after transplantation, flow cytometric analysis of the donor-specific chimerism showed 1.11 percent of double-positive CD4FITC/RT1Ac-Cy7 and 1.43 percent of double-positive CD8PE/RT1Ac-Cy7 T-cell populations in the peripheral blood of hemiface allotransplant recipients. The chimerism level of double-positive CD4FITC/RT1Ac-Cy7 T cells increased to 3.39 percent, whereas it remained stable for the double-positive CD8PE/RT1Ac-Cy7 T-cell population at day 63 after transplantation (1.00 percent). The mixed lymphocyte reaction assay at day 160 after transplantation revealed donor-specific tolerance to donor (Lewis-Brown Norway) antigens and strong reactivity to the third-party (ACI) alloantigens. In this study, donor-specific chimerism and functional tolerance were induced in hemifacial allograft transplants across the major histocompatibility complex barrier under cyclosporine A monotherapy protocol. This model will allow further studies on tolerance induction protocols.  相似文献   
68.
The genetic diversity of Cryptosporidium in reptiles was analyzed by PCR-restriction fragment length polymorphism and sequence analysis of the small subunit rRNA gene. A total of 123 samples were analyzed, of which 48 snake samples, 24 lizard samples, and 3 tortoise samples were positive for Cryptosporidium: Nine different types of Cryptosporidium were found, including Cryptosporidium serpentis, Cryptosporidium desert monitor genotype, Cryptosporidium muris, Cryptosporidium parvum bovine and mouse genotypes, one C. serpentis-like parasite in a lizard, two new Cryptosporidium spp. in snakes, and one new Cryptosporidium sp. in tortoises. C. serpentis and the desert monitor genotype were the most common parasites and were found in both snakes and lizards, whereas the C. muris and C. parvum parasites detected were probably the result of ingestion of infected rodents. Sequence and biologic characterizations indicated that the desert monitor genotype was Cryptosporidium saurophilum. Two host-adapted C. serpentis genotypes were found in snakes and lizards.  相似文献   
69.
Ingested fat releases CCK, causes gastric relaxation, delays gastric emptying, and limits meal size; however, the mechanistic link among these actions has not been established. Fatty acid release of CCK is chain-length sensitive; dodecanoic acid (C12) induces greater CCK release than decanoic acid (C10). The effect of C12 or C10 on tolerance to subsequent intragastric infusion of liquid was determined in healthy subjects, with and without the CCK(1) receptor antagonist dexloxiglumide. Gastric wall relaxation after either fatty acid was assessed by graded volume distension and by barostat; gastric emptying was measured by gastric aspiration and by a [(13)C]octanoic acid breath technique. C12 released more CCK (mean plasma CCK after vehicle, 4.7 +/- 0.8 pM; C10, 4.8 +/- 0.3 pM; C12, 8 +/- 1.2 pM; P < 0.05 C12 vs. C10 or vehicle) and reduced the volume of water (and of 5 and 25% glucose solutions) delivered at maximum tolerance compared with C10 or vehicle (volume of water tolerated after vehicle, 1,535 +/- 164 ml; C10, 1,335 +/- 160 ml; C12, 842 +/- 103 ml; P < 0.05 C12 vs. C10 or vehicle); this effect was abolished by dexloxiglumide. Intragastric volumes were always similar at the limit of tolerance, and, whereas gastric relaxation occurred to similar degrees after the fatty acids, its duration was longer after C12, which also induced a longer delay in half-gastric emptying [t(1/2)(min) after vehicle, 53 +/- 2; C10, 67 +/- 3; C12, 88 +/- 7; P < 0.05 C12 vs. C10 or vehicle]. In conclusion, ingestion of a CCK-releasing fatty acid reduces the tolerated volume of liquid delivered into the stomach, primarily via a CCK(1) receptor-mediated delay in gastric emptying.  相似文献   
70.
Ribozymes: A modern tool in medicine   总被引:6,自引:0,他引:6  
Since the discovery of ribozymes and self-splicing introns, it has been estimated that this biological property of RNA combined with other recombinant DNA technologies would become a tool to combat viral diseases and control oncogenes. These goals seem like a distinct possibility now. However, there is still a lot to be learned about the mobility of RNA inside the cells and the cellular factors that can impede ribozyme action in order to capitalize fully on the targeted RNA inactivation property of ribozymes. The most effective approach to maximize ribozyme function in a complex intracellular environment is to understand as much as possible about the intracellular fate of the RNA that is being targeted. As new techniques in cell biology become available, such understanding will be less problematic. Fundamental studies of ribozyme structure and mechanism of catalysis are flourishing both at the academic and industrial level and it can be expected that many new developments will continue to take place in these areas in the near future. Here, we review the design, stability and therapeutic application of these technologies illustrating relevant gene targets and applications in molecular medicine. Relevant problems in implementation of the technology, group I and II introns and the differences in applications, ribozyme structure and the application of this technology to virus attack and oncogene downregulation are discussed. Also some of the latest RNA-based technologies such as siRNA, RNA/DNA duplexes and RNA decoys have been introduced.  相似文献   
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