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31.
32.
Retroposed new genes out of the X in Drosophila 总被引:12,自引:0,他引:12
New genes that originated by various molecular mechanisms are an essential component in understanding the evolution of genetic systems. We investigated the pattern of origin of the genes created by retroposition in Drosophila. We surveyed the whole Drosophila melanogaster genome for such new retrogenes and experimentally analyzed their functionality and evolutionary process. These retrogenes, functional as revealed by the analysis of expression, substitution, and population genetics, show a surprisingly asymmetric pattern in their origin. There is a significant excess of retrogenes that originate from the X chromosome and retropose to autosomes; new genes retroposed from autosomes are scarce. Further, we found that most of these X-derived autosomal retrogenes had evolved a testis expression pattern. These observations may be explained by natural selection favoring those new retrogenes that moved to autosomes and avoided the spermatogenesis X inactivation, and suggest the important role of genome position for the origin of new genes. 相似文献
33.
Comparison of C(18)-carboxypropylbetaine and standard N-acetyl-L-cysteine-NaOH processing of respiratory specimens for increasing tuberculosis smear sensitivity in Brazil
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Scott CP Dos Anjos Filho L De Queiroz Mello FC Thornton CG Bishai WR Fonseca LS Kritski AL Chaisson RE Manabe YC 《Journal of clinical microbiology》2002,40(9):3219-3222
Techniques to improve the sensitivity of smear microscopy would facilitate early tuberculosis (TB) diagnosis and disease control, especially in low-income countries where the positive predictive value is high. C(18)-carboxypropylbetaine (CB-18) is a zwitterionic detergent that helps to compensate for the innate buoyancy of mycobacteria, potentially enhancing recovery by centrifugation. Previous data suggest that CB-18 may increase the sensitivity of smear, culture, and molecular amplification diagnostic testing. The goal of the present study was to evaluate if the sensitivity of the smear technique using light microscopy could be improved by treating respiratory samples with CB-18. In the first phase, respiratory specimens were collected consecutively from patients with suspected pulmonary tuberculosis in a tertiary-care hospital in Rio de Janeiro, Brazil (236 specimens were analyzed). After protocol modifications, another 120 respiratory specimens were evaluated. The standard technique was N-acetyl-L-cysteine with sodium hydroxide (NALC-NaOH) treatment, smear concentration with centrifugation, and Ziehl-Neelsen staining. Culture on L?wenstein-Jensen slants was performed on all specimens for use as the "gold standard." No specimens from patients undergoing active TB treatment were included. The initial protocol for CB-18 processing resulted in a sensitivity of 59.6% and specificity of 96.8% compared to standard processing with a sensitivity of 66.0% and specificity of 96.8%. Using the modified protocol, the sensitivity of CB-18 increased to 71.4% with a specificity of 97.0% versus standard processing with a sensitivity of 61.9% and a specificity of 99.0%. The diagnostic yield of acid-fast bacillus smear with CB-18 in the absence of fluorescence microscopy and PCR compared to standard processing with NALC-NaOH was not significantly different, although the power to detect a difference by the modified assay was low. 相似文献
34.
Autologous mixed lymphocyte reaction in man. XIV. Deficiency of the autologous mixed lymphocyte reaction in acquired immune deficiency syndrome (AIDS) and AIDS related complex (ARC). In vitro effect of purified interleukin-1 and interleukin-2. 总被引:2,自引:7,他引:2
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Peripheral blood mononuclear cells from male homosexuals with acquired immune deficiency syndrome (AIDS) and with AIDS related complex (ARC) were examined for the autologous mixed lymphocyte reaction (AMLR) between responder T and irradiated autologous non-T cells and in vitro influence of purified human interleukin-1 (IL-1) and -2 (IL-2) on the AMLR. The AMLR was significantly (P less than 0.001) deficient in both ARC and AIDS; the deficiency of the AMLR was of the similar magnitude in two groups when compared to asymptomatic homosexuals and healthy heterosexuals. In vitro addition of IL-2 enhanced the AMLR to the baseline levels of control subjects in most patients in ARC group (P less than 0.01) and in four of 15 patients in AIDS group (P less than 0.01). Addition of IL-1 to IL-2 containing cultures resulted in no further increase in the AMLR response over those with IL-2 alone. This study demonstrates deficiency of the AMLR in patients with ARC and AIDS that is corrected by purified IL-2 in the majority of cases with ARC but only a subset of patients with AIDS. The significance of these findings is discussed. 相似文献
35.
The effect of the anaesthetic, Propofol, on in-vitro oocyte maturation, fertilization and cleavage in mice 总被引:3,自引:4,他引:3
Propofol is a common anaesthetic agent used for oocyte retrieval procedures
during in-vitro fertilization (IVF). The effect of Propofol in vitro on
mouse oocyte maturation, fertilization and embryo cleavage was studied. In
this study, 551 cumulus-free and 222 cumulus-enclosed oocytes from mice
stimulated with pregnant mare's serum gonadotrophin (PMSG) were incubated
for 30 min in medium containing 0, 100, 1000 or 10,000 ng/ml of Propofol
prior to in-vitro maturation. Also, 325 cumulus-enclosed oocytes from mice
stimulated to ovulate with PMSG/human chorionic gonadotrophin (HCG) were
incubated for 30 min in similar concentrations of Propofol prior to IVF.
Maturation, fertilization and cleavage rates were compared. A significant
decrease in the in-vitro maturation rate was observed only when the
cumulus-free and cumulus-enclosed oocytes were exposed to 10,000 ng/ml
Propofol (P < 0.0074 and P < 0.0001 respectively). Fertilization and
embryo cleavage rates were not significantly different compared with the
controls. These findings give some reassurance with respect to human IVF.
However, further studies on the potential effects of Propofol on
implantation and pregnancy outcome following IVF are needed.
相似文献
36.
Age-related deficits in brain androgen binding and metabolism, testosterone, and sexual behavior of male rats 总被引:1,自引:0,他引:1
Brain androgen binding and metabolism, serum testosterone (T), and sexual behavior were measured in old and young male Fischer 344 rats. After completion of sexual behavior tests, blood was collected for T assay and brains were removed for simultaneous measurements of cytosolic (ARc) and nuclear (ARn) androgen receptors and aromatase activity (AA) in the preoptic area (POA), hypothalamus (HYP) and amygdala (AMG). In Experiment 1, old and young intact males were examined. None of the old males ejaculated in any of the tests of sexual behavior whereas all of the young males ejaculated. The old males had lower levels of serum T, lower levels of ARn in the POA and HYP and lower levels of AA in the POA. The ARc levels of the old and young males did not differ. Experiment 2 was designed to determine if the deficits in brain androgen binding and metabolism were due to low levels of T. Old and young T-treated gonadectomized (GX-T) males and young intact (I) males were examined. T levels were comparable in the young and old GX-T males and were higher in each of these groups than in the young I males. In sexual behavior tests, all of the young but only 25% of the old GX-T males ejaculated. Although ARn levels in the old GX-T males were lower than in the young GX-T males, they were comparable to the young I male levels. No age-related differences in T induction of AA were observed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
37.
W G McCluggage H Bharucha L M Caughley A Date P W Hamilton C M Thornton M Y Walsh 《Journal of clinical pathology》1996,49(10):833-835
AIMS: To assess interobserver variation in reporting cervical colposcopic biopsy specimens and to determine whether a modified Bethesda grading system results in better interobserver agreement than the traditional cervical intraepithelial neoplasia (CIN) grading system. METHODS: One hundred and twenty five consecutive cervical colposcopic biopsy specimens were assessed independently by six histopathologists. Specimens were classified using the traditional CIN grading system as normal, koilocytosis, CIN I, CIN II, or CIN III. The specimens were also classified using a modified Bethesda grading system as either normal, low grade squamous intraepithelial lesion (LSIL) or high grade squamous intraepithelial lesion (HSIL). Participants were also asked to categorise biopsy specimens by the CIN system with the addition of the recently proposed category "basal abnormalities of uncertain significance (BAUS)". The degree of agreement between participants was assessed by kappa statistics. RESULTS: Using the CIN system, interobserver agreement was generally poor: unweighted and weighted kappa values between individual pairs of observers ranging from 0.05 to 0.34 (average 0.20) and from 0.20 to 0.54 (average 0.36), respectively. With the modified Bethesda system, interobserver agreement was better but still poor: unweighted and weighted kappa values ranging from 0.15 to 0.58 (average 0.30) and from 0.21 to 0.61 (average 0.36), respectively. There was little or no agreement between observers in the diagnosis of BAUS. CONCLUSIONS: Interobserver agreement in the reporting of cervical colposcopic biopsy specimens using the CIN grading system is poor. Agreement, while still poor, is better when a modified Bethesda grading system is used. There is little or no consensus in the diagnosis of BAUS. 相似文献
38.
The virulent fish pathogen Aeromonas salmonicida was rapidly killed in vivo when restricted inside a diffusion chamber implanted intraperitoneally in rainbow trout. After a period of regrowth, the survivors had acquired resistance to host-mediated bacteriolysis, phagocytosis, and oxidative killing, properties which were subsequently lost by growth in vitro. Resistance to bacteriolysis and phagocytosis was associated with a newly acquired capsular layer revealed by acidic polysaccharide staining and electron microscopy. This capsular layer shielded the underlying, regular surface array (S-layer) from immunogold labeling with a primary antibody to the S-layer protein. Resistance to oxidative killing was mediated by a mechanism not associated with the presence of the capsular layer. An attenuated vaccine strain of A. salmonicida grown in vivo failed to express the capsular layer. Consequently, the in vivo-grown cells of this attenuated strain remained as sensitive to bacteriolysis, and as avidly adherent to macrophages, as the in vitro-grown cells. The importance of these new virulence determinants and their relation to the known virulence factors of A. salmonicida are discussed. 相似文献
39.
Tyrer P Thompson S Schmidt U Jones V Knapp M Davidson K Catalan J Airlie J Baxter S Byford S Byrne G Cameron S Caplan R Cooper S Ferguson B Freeman C Frost S Godley J Greenshields J Henderson J Holden N Keech P Kim L Logan K Manley C MacLeod A Murphy R Patience L Ramsay L De Munroz S Scott J Seivewright H Sivakumar K Tata P Thornton S Ukoumunne OC Wessely S 《Psychological medicine》2003,33(6):969-976
BACKGROUND: We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD: Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS: Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION: Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined. 相似文献
40.
AIMS: To investigate the histogenesis of paratesticular adenomatoid tumour by use of immunohistochemical markers for a variety of carcinomas and mesothelioma. METHODS AND RESULTS: Immunohistochemical staining of sections from 12 cases of paratesticular adenomatoid tumour was undertaken using primary antibodies to antigens expressed by benign epithelial cells and carcinoma (cytokeratin AE1/AE3, cytokeratin 34ssE12, epithelial membrane antigen, MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1), stromal and vascular markers (vimentin, CD34, factor VIII), and mesothelioma-associated antigens (thrombomodulin, HBME-1, OC 125) and p53 protein. There was absence of immunohistochemical expression of epithelial/carcinoma markers MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1 and to factor VIII and CD34. All tumours expressed cytokeratin AE1/AE3, epithelial membrane antigen and vimentin, with weak expression of cytokeratin 34ssE12 in 25% of tumours. Each tumour showed expression of thrombomodulin, HBME-1 and OC 125 in a membranous distribution. p53 protein expression was not detected. CONCLUSIONS: The immunohistochemical profile of paratesticular adenomatoid tumour is strongly supportive of a mesothelial cell origin. 相似文献