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991.
Seminal plasma alpha-glucosidase activity and male infertility 总被引:7,自引:1,他引:7
Mahmoud AM; Geslevich J; Kint J; Depuydt C; Huysse L; Zalata A; Comhaire FH 《Human reproduction (Oxford, England)》1998,13(3):591-595
Measurement of alpha-glucosidase (alpha-GLUC) activity by means of a simple
colorimetric test using a commercial kit (EpiScreen; FertiPro, Lotenhulle,
Belgium) yielded results that were strongly correlated with the values
obtained for the neutral iso-enzyme measured by a fluorimetric reference
method (r=0.85, P=0.003, n=13). The former method was characterized by a
low intra- and inter-coefficient of variation (6.6 and 4.3% respectively).
Vasectomized men with azoospermia (n=27) had a significantly lower
alpha-GLUC activity in semen than vasectomized men with residual
spermatozoa present (n=11, P < 0.01) and men with azoospermia of primary
testicular origin (n=33, P < 0.01). Receiver operating curve (ROC)
analysis showed alpha-GLUC measurement to be reasonably accurate in
differentiation between cases with obstructive versus testicular
azoospermia at criterion value 13.5 U/l (sensitivity=82%, specificity=
70%). In cases with spermatozoa present, alpha-GLUC activity and output per
ejaculate were positively correlated with sperm concentration (r=0.53 and
0.38, n=472), linear velocity (r=0.35 and 0.30, n=224), curvilinear
velocity (r=0.32 and r=0.29, n=224), semen adenosine triphosphate (r=0.35
and 0.26, n=64), the concentration of 5alpha-dihydrotestosterone (r=0.31
and 0.29, n=74), and gamma-glutamyltransferase activity (r=0.62 and 0.32,
n=275) in seminal plasma. The activity of alpha-GLUC was inversely
correlated with ROS generation after 12-myristate, 13-acetate phorbol ester
stimulation (r=-0.27, n=104), and both alpha-GLUC activity and total output
were inversely correlated with the concentration of peroxidase- positive
white blood cells among samples with > or =1x10(6)/ml of these cells
(r=-0.30 and -0.19, n=165). It is concluded that simple photometric
measurement of alpha-GLUC activity in seminal plasma reflects the
functional state of the epididymis and may be helpful for the differential
diagnosis of certain cases with azoospermia.
相似文献
992.
993.
Srikar Anagoni Nagaraja Mudhigeti Mohan Alladi Verma Anju Padmalatha AM Usha Kalawat 《Indian journal of medical microbiology》2022,40(3):427-432
PurposeA large number of new molecular or virology laboratories have been established to increase the testing capacity for SARS-CoV-2. Due to heavy workload, there is delay in testing of samples. In order to avoid the negative effect of delayed testing on RTPCR results guidelines are issued from WHO and CDC to transport samples in cold chain. However, in pandemic situations the recommended guidelines for transport and storage conditions are often compromised. This study was conducted to evaluate the effect of sample storage conditions at different temperatures on the results of RT PCR test.MethodsTotal 275 samples were included in this study, among these 126 samples tested positive and 149 samples tested negative. All samples were aliquoted into two and the aliquotes stored in duplicate at 4 ?°C and room temperature. All aliquots stored at both the temperatures were tested by RTPCR every 24 hours up to 5 days.ResultsDiagnostic accuracy decreased from day1 to day 5 at both the storage temperatures i,e 4 ?°C and room temperature in comparison to the initial day results. Positivity decreased on an average of 9.02% at 4 ?°C and at 9.27% at room temperature per day. Among total 126 positive samples on an average false negative and failure of internal control at 4 ?°C and room temperature was 8.86%, 8.22% and 3.64%, and 4.12%, respectively. All the samples with CT value ?< ?30 remained positive at both temperatures up to 5 days. Few samples with >30 CT value showed variable results i.e. positive, negative or internal control failure from day 1 (2nd day after sample collection) onwards.ConclusionsThere was no significant difference between RT PCR results of samples stored at 4 ?°C and room temperature up to 5 days of collection. However internal control failure was more in samples stored at room temperature. Therefore, samples received without cold chain also may be processed by RTPCR and should not be rejected. 相似文献
994.
Evaluation of the performance of hysterosalpingo contrast sonography in 500 consecutive, unselected, infertile women 总被引:1,自引:1,他引:1
Hamilton JA; Larson AJ; Lower AM; Hasnain S; Grudzinskas JG 《Human reproduction (Oxford, England)》1998,13(6):1519-1526
The performance of hysterosalpingo contrast sonography (Hy Co Sy) as a
first-line, outpatient investigation of tubal patency was examined in 500
consecutive, infertile women, at one centre. Hy Co Sy was completed in 463
(92.6%) cases, using a galactose microbubble contrast agent (Echovist-200)
and transvaginal sonography. Initial plain scanning identified adnexal
pathology in 198 women (39.6%). Examination with Echovist was attempted for
905 tubes and only 67 (7.4%) were not assessable; after the first 100 women
this decreased to 35 tubes (4.8%). A sonographic appearance compatible with
blocked tubes was found on 118 (14.1%) occasions but it was also possible
to identify variations in the appearance/filling/spilling patterns of
individual tubes which increased the number assessed as abnormal to 193
(23.0%). Comparison with laparoscopy and dye chromopertubation findings
from the past three years was possible for 185 (37%) women, representing
282 tubes, which gave Hy Co Sy an overall concordance rate of 85.8%,
sensitivity of 90.4%, specificity of 70.3%, positive predictive value of
91.2% and negative predictive value of 68.2%. Some 51.0% of women described
only mild discomfort and there were no significant postprocedure
complications. Hy Co Sy appears to be an acceptable first- line screen and
may select out women in whom more invasive investigations are likely to
reveal pathology.
相似文献
995.
996.
Identification and characterization of a novel genomic island integrated at selC in locus of enterocyte effacement-negative, Shiga toxin-producing Escherichia coli
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Schmidt H Zhang WL Hemmrich U Jelacic S Brunder W Tarr PI Dobrindt U Hacker J Karch H 《Infection and immunity》2001,69(11):6863-6873
The selC tRNA gene is a common site for the insertion of pathogenicity islands in a variety of bacterial enteric pathogens. We demonstrate here that Escherichia coli that produces Shiga toxin 2d and does not harbor the locus of enterocyte effacement (LEE) contains, instead, a novel genomic island. In one representative strain (E. coli O91:H(-) strain 4797/97), this island is 33,014 bp long and, like LEE in E. coli O157:H7, is integrated 15 bp downstream of selC. This E. coli O91:H(-) island contains genes encoding a novel serine protease, termed EspI; an adherence-associated locus, similar to iha of E. coli O157:H7; an E. coli vitamin B12 receptor (BtuB); an AraC-type regulatory module; and four homologues of E. coli phosphotransferase proteins. The remaining sequence consists largely of complete and incomplete insertion sequences, prophage sequences, and an intact phage integrase gene that is located directly downstream of the chromosomal selC. Recombinant EspI demonstrates serine protease activity using pepsin A and human apolipoprotein A-I as substrates. We also detected Iha-reactive protein in outer membranes of a recombinant clone and 10 LEE-negative, Shiga toxin-producing E. coli (STEC) strains by immunoblot analysis. Using PCR analysis of various STEC, enteropathogenic E. coli, enterotoxigenic E. coli, enteroaggregative E. coli, uropathogenic E. coli, and enteroinvasive E. coli strains, we detected the iha homologue in 59 (62%) of 95 strains tested. In contrast, espI and btuB were present in only two (2%) and none of these strains, respectively. We conclude that the newly described island occurs exclusively in a subgroup of STEC strains that are eae negative and contain the variant stx(2d )gene. 相似文献
997.
Myocardial contraction bands revisited 总被引:2,自引:0,他引:2
998.
Linkage analysis of candidate regions for coeliac disease genes 总被引:5,自引:0,他引:5
Houlston RS; Tomlinson IP; Ford D; Seal S; Marossy AM; Ferguson A; Holmes GK; Hosie KB; Howdle PD; Jewell DP; Godkin A; Kerr GD; Kumar P; Logan RF; Love AH; Johnston S; Marsh MN; Mitton S; O'Donoghue D; Roberts A; Walker-Smith JA; Stratton MF 《Human molecular genetics》1997,6(8):1335-1339
A strong HLA association is seen in coeliac disease [specifically to the
DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account
for the increased risk seen in relatives of affected cases. One or more
genes at HLA-unlinked loci also predispose to coeliac disease and are
probably stronger determinants of disease susceptibility than HLA. A recent
study has proposed a number of candidate regions on chromosomes 6p23
(distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3,
19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked
susceptibility gene. We have examined these regions in 28 coeliac disease
families by linkage analysis. There was excess sharing of chromosome 6p
markers, but no support for a predisposition locus telomeric to HLA. No
significant evidence in favour of linkage to coeliac disease was obtained
for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or
22cen. There was, however, excess sharing close to D15S642. The maximum
non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for
linkage of coeliac disease to chromosome 15q26 is not strong, the well
established association between coeliac disease and insulin dependent
diabetes mellitus, together with the mapping of an IDDM susceptibility
locus (IDDM3) to chromosome 15q26, provide indirect support for this as a
candidate locus conferring susceptibility to coeliac disease in some
families.
相似文献
999.
Germline mutations of the MEN1 gene in familial multiple endocrine neoplasia type 1 and related states 总被引:9,自引:0,他引:9
Agarwal SK; Kester MB; Debelenko LV; Heppner C; Emmert-Buck MR; Skarulis MC; Doppman JL; Kim YS; Lubensky IA; Zhuang Z; Green JS; Guru SC; Manickam P; Olufemi SE; Liotta LA; Chandrasekharappa SC; Collins FS; Spiegel AM; Burns AL; Marx SJ 《Human molecular genetics》1997,6(7):1169-1175
Familial multiple endocrine neoplasia type 1 (FMEN1) is an autosomal
dominant trait characterized by tumors of the parathyroids, gastro-
intestinal endocrine tissue, anterior pituitary and other tissues. We
recently cloned the MEN1 gene and confirmed its identity by finding
mutations in FMEN1. We have now extended our mutation analysis to 34 more
unrelated FMEN1 probands and to two related states, sporadic MEN1 and
familial hyperparathyroidism. There was a high prevalence of heterozygous
germline MEN1 mutations in sporadic MEN1 (8/11 cases) and in FMEN1 (47/50
probands). One case of sporadic MEN1 was proven to be a new MEN1 mutation.
Eight different mutations were observed more than once in FMEN1. Forty
different mutations (32 FMEN1 and eight sporadic MEN1) were distributed
across the MEN1 gene. Most predicted loss of function of the encoded menin
protein, supporting the prediction that MEN1 is a tumor suppressor gene. No
MEN1 germline mutation was found in five probands with familial
hyperparathyroidism, suggesting that familial hyperparathyroidism often is
caused by mutation in another gene or gene(s).
相似文献
1000.