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991.
Two frequent missense mutations in Pendred syndrome 总被引:8,自引:3,他引:8
Van Hauwe P; Everett LA; Coucke P; Scott DA; Kraft ML; Ris-Stalpers C; Bolder C; Otten B; de Vijlder JJ; Dietrich NL; Ramesh A; Srisailapathy SC; Parving A; Cremers CW; Willems PJ; Smith RJ; Green ED; Van Camp G 《Human molecular genetics》1998,7(7):1099-1104
Pendred syndrome is an autosomal recessive disorder characterized by early
childhood deafness and goiter. A century after its recognition as a
syndrome by Vaughan Pendred, the disease gene ( PDS ) was mapped to
chromosome 7q22-q31.1 and, recently, found to encode a putative sulfate
transporter. We performed mutation analysis of the PDS gene in patients
from 14 Pendred families originating from seven countries and identified
all mutations. The mutations include three single base deletions, one
splice site mutation and 10 missense mutations. One missense mutation
(L236P) was found in a homozygous state in two consanguineous families and
in a heterozygous state in five additional non-consanguineous families.
Another missense mutation (T416P) was found in a homozygous state in one
family and in a heterozygous state in four families. Pendred patients in
three non-consanguineous families were shown to be compound heterozygotes
for L236P and T416P. In total, one or both of these mutations were found in
nine of the 14 families analyzed. The identification of two frequent PDS
mutations will facilitate the molecular diagnosis of Pendred syndrome.
相似文献
992.
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994.
GM Hafen C Hurst J Yearwood J Smith Z Dzalilov PJ Robinson 《BMC medical informatics and decision making》2008,8(1):44
Background
Cystic fibrosis is the most common fatal genetic disorder in the Caucasian population. Scoring systems for assessment of Cystic fibrosis disease severity have been used for almost 50 years, without being adapted to the milder phenotype of the disease in the 21st century. The aim of this current project is to develop a new scoring system using a database and employing various statistical tools. This study protocol reports the development of the statistical tools in order to create such a scoring system. 相似文献995.
The human corpus luteum: reduction in macrophages during simulated maternal recognition of pregnancy 总被引:2,自引:0,他引:2
It has been shown that immune cells, particularly macrophages, accumulate
in the corpus luteum during luteolysis. This study aimed to investigate the
effect of maternal recognition of pregnancy on the localization and numbers
of macrophages in the human corpus luteum. Corpora lutea (n = 12) were
obtained from normally cycling women at the time of hysterectomy and were
dated on the basis of serial urinary luteinizing hormone (LH) estimation.
In addition, corpora lutea (n = 4) were collected from women who had
received daily doubling doses of human chorionic gonadotrophin (HCG) to
mimic the hormonal changes of early pregnancy. Macrophages were localized
by immunohistochemistry using an anti-CD68 antibody. Steroidogenic cells,
steroidogenic cells of thecal origin and endothelial cells were identified
on serial sections by immunohistochemistry for 3beta-hydroxysteroid
dehydrogenase, 17alpha-hydroxylase and von Willebrand factor, respectively.
The luteal cells capable of responding directly to HCG were identified by
isotopic in-situ hybridization for messenger RNA encoding LH/HCG receptors.
Macrophages were localized primarily to the vascular connective tissue and
theca-lutein areas of the corpus luteum, although some were found in the
granulosa-lutein cell layer. Macrophage numbers increased throughout the
luteal phase to a maximum in the late- luteal phase (P < 0.05). Luteal
'rescue' with HCG was associated with a marked reduction in the numbers of
tissue macrophages when compared with those of the late-luteal phase (P
< 0.001). One of the effects of HCG during maternal recognition of
pregnancy is to prevent the normal influx of macrophages into the corpus
luteum. As LH/HCG receptors localized to the steroidogenic cells, this
implies a fundamental role for steroidogenic cell products in the control
of macrophage influx into the human corpus luteum.
相似文献
996.
AIM: To compare an ultrasonic height measuring device (Gulliver) with mechanical stadiometry and the classical "book and tape measure" method. METHODS: Blinded duplicate measurements of height were made on each of 14 children by a pair of observers using a stadiometer (H) and Gulliver (G). Height was measured on a further 18 children by parents and an auxologist using Gulliver and the book and tape method (TM), and the results were compared with those obtained with a single stadiometry measurement. Finally, measurement of a rigid metal box was made on 10 occasions by the three methods. RESULTS: In the group of 14 children, the mean difference (range) in height (H minus G) was +2.8 cm (+0.5 to +4.55 cm), with H giving a systematically higher value in 276 of 280 individual measurements. In the group of 18 children, height by H was greater than by G or TM in 47 of 52 individual measurements. The mean (SD) height of the box by H (61.60 (0.07) cm) was greater than by G (60.96 (0.15) cm; p < 0.001) but not TM (61.4 (0.16) cm; p > 0.05). G and TM produced three times less reliable estimations of height than H, but with a large difference in cost, and there was evidence of systematic underrecording of height by 0.5 cm with G. CONCLUSIONS: Stadiometry is precise and reproducible, and can detect true changes in height over one month periods in mid-childhood, and should remain the standard way of observing growth. The book and tape method can produce clinically acceptable quarterly estimations of height that can be performed in the home. 相似文献
997.
Measured haplotype analysis of the angiotensin-I converting enzyme gene 总被引:20,自引:5,他引:20
Keavney B; McKenzie CA; Connell JM; Julier C; Ratcliffe PJ; Sobel E; Lathrop M; Farrall M 《Human molecular genetics》1998,7(11):1745-1751
Linkage and segregation analysis have shown that circulating angiotensin-I
converting enzyme (ACE) levels are influenced by a major quantitative trait
locus that maps within or close to the ACE gene. The D variant of a 287 bp
insertion/deletion (I/D) polymorphism in intron 16 of the gene is
associated with high ACE levels and may also be related to increased risk
of cardiovascular disease. Multiple variants that are in linkage
disequilibrium with the I/D polymorphism have been described, but it is
unknown if any of these are directly implicated, alone or in combination
with as yet undiscovered variants, in the determination of ACE levels. An
analysis of 10 polymorphisms spanning 26 kb of the ACE gene revealed a
limited number of haplotypes in Caucasian British families due to strong
linkage disequilibrium operating over this small chromosomal region. A
haplotype tree (cladogram) was constructed with three main branches (clades
A-C) which account for 90% of the observed haplotypes. Clade C is most
likely derived from clades A and B following an ancestral recombination
event. This evolutionary information was then used to direct a series of
nested, measured haplotype analyses that excluded upstream sequences,
including the ACE promoter, from harbouring the major ACE-linked variant
that explains 36% of the total trait variability. Residual familial
correlations were highly significant, suggesting the influence of
additional unlinked genes. Our results demonstrate that a combined
cladistic/measured haplotype analysis of polymorphisms within a gene
provides a powerful means to localize variants that directly influence a
quantitative trait.
相似文献
998.
A small vertical screen oxygenator was built using a stainless steel screen enclosed in a Plexiglas box as the oxygenating surface. The unit was primed with 35 ml dextran-diluted blood (Hct 25.1 +/- 0.6%. mean +/- SE) and tested in cats with a partial cardiopulmonary bypass circuit. An oxygen saturation of more than 95% was always obtained, even when the incoming venous saturation was as low as 15%. The O2 exchange capacity was minimally affected by changes in blood flow (1.5 to 70 ml/min) through the unit. CO2 extraction was not flow limited over the range tested. Output PCO2 was 33.3 +/- 0.6 mmHg and pH was 7.29 +/- 0.02. These results were obtained when 3% CO2 in O2 was passed through the oxygenator chamber at 1.0 to 5.0 l/min. The performance of the unit was stable for periods up to 4 h. The small priming volume and reliable performance make this oxygenator suitable for organ perfusion in small experimental animals. 相似文献
999.
Hilton PJ; Taylor J; Forni LG; Treacher DF 《QJM : monthly journal of the Association of Physicians》1998,91(4):279-283
Continuous haemofiltration with lactate-based replacement fluid is widely
used for the treatment of acute renal failure (ARF). In the presence of
lactic acidosis, such treatment exacerbates rather than improves the
clinical state. Continuous haemofiltration using a locally- prepared
bicarbonate-based replacement fluid was performed in 200 patients over 7
years. All the patients had ARF with concomitant lactic acidosis, or
demonstrated lactate intolerance after starting haemofiltration with
lactate-based replacement fluids. In every case it was possible to correct
the acidosis without inducing either extracellular volume expansion or
hypernatraemia. In 89 patients (45%), the lactic acidosis resolved while
being treated with bicarbonate-based haemofiltration. Fifty-seven patients
(28.5%) survived. Significant differences at presentation in the group who
survived, compared with those who died, were seen in age (50.8 vs. 57.1),
mean arterial pressure (68.5 vs. 60.0 mmHg) and APACHE II score (32.1 vs.
38.9). Neither the severity of the presenting acidosis nor the arterial
blood lactate appeared to predict outcome. Patients who developed ARF and
lactic acidosis after cardiac surgery had a low survival rate. The
combination of ARF and lactic acidosis that cannot safely be treated by
haemofiltration using lactate-based replacement fluids can be managed with
bicarbonate-based haemofiltration.
相似文献
1000.
RG Strauss ; GA Ludwig ; MV Smith ; PJ Villhauer ; MJ Randels ; A Smith-Floss ; TA Koerner 《Transfusion》1994,34(2):116-121
BACKGROUND: Historically, paid blood donors were found to transmit hepatitis at higher rates than volunteers. In those older studies, paid donors frequently were recruited from prisons or slum areas–a finding consistent with the belief that monetary payment in itself did not necessarily lead to the high-risk status of commercial blood. Instead, it was the population base from which the donors were recruited that was important. STUDY DESIGN AND METHODS: Today, cytapheresis donors are in great demand. Because payment is one incentive that might entice donors to undertake the increased commitment of repeated cytapheresis donation, the results were studied of infectious disease history and laboratory testing performed concurrently in 917 volunteer whole-blood donors and 1240 paid cytapheresis donors, who were enrolled in distinct programs at the DeGowin Blood Center from October 7, 1987, through November 30, 1990. RESULTS: When first, repeat, and overall donations made by these donors were evaluated separately, paid cytapheresis donors were found to exhibit no increase in infectious disease history or test results beyond those of volunteer whole-blood donors. CONCLUSION: Thus, paid cytapheresis donors, when managed within a formal program, should not necessarily be presumed to be more dangerous than volunteers, from an infectious disease aspect. However, definitive proof of safety (comparison of transfusion-transmitted infection rates in two groups of patients receiving blood components exclusively from either paid cytapheresis or volunteer donors) was not pursued by long- term follow-up studies. 相似文献