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31.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
32.
Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
相似文献
33.
ATRX encodes a novel member of the SNF2 family of proteins: mutations point to a common mechanism underlying the ATR-X syndrome 总被引:11,自引:3,他引:11
Picketts DJ; Higgs DR; Bachoo S; Blake DJ; Quarrell OW; Gibbons RJ 《Human molecular genetics》1996,5(12):1899-1907
It was shown recently that mutations of the ATRX gene give rise to a
severe, X-linked form of syndromal mental retardation associated with alpha
thalassaemia (ATR-X syndrome). In this study, we have characterised the
full-length cDNA and predicted structure of the ATRX protein. Comparative
analysis shows that it is an entirely new member of the SNF2 subgroup of a
superfamily of proteins with similar ATPase and helicase domains. ATRX
probably acts as a regulator of gene expression. Definition of its genomic
structure enabled us to identify four novel splicing defects by screening
52 affected individuals. Correlation between these and previously
identified mutations with variations in the ATR-X phenotype provides
insights into the pathophysiology of this disease and the normal role of
the ATRX protein in vivo.
相似文献
34.
Rapid discrimination of Mycobacterium tuberculosis strains by random amplified polymorphic DNA analysis. 总被引:5,自引:8,他引:5
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Investigations of the epidemiology of tuberculosis have been hampered by the lack of strain-specific markers that can be used to differentiate isolates of Mycobacterium tuberculosis. We report the development of a rapid protocol for random amplified polymorphic DNA analysis which included the use of a commercially available DNA extraction kit (GeneReleaser). This was applied to 14 strains of M. tuberculosis, including strains associated with temporal and geographical clusters of tuberculosis in the United Kingdom and those from India, Africa, and Saudi Arabia. Strains of M. tuberculosis could be discriminated in about 8 h by this method, which is therefore a rapid and simple alternative to restriction fragment length polymorphism analysis. 相似文献
35.
DJ SINGH 《Medical Journal Armed Forces India》1996,52(4):239-241
Stress fractures amongst military recruits are limited to the lower extremities; yet involvement of the shaft of the femur is unusual. Seven such cases in a series of 352 stress fractures are presented. The importance of early recognition and management is emphasized with a view to prevent bony disruption in an otherwise easily treatable condition.KEY WORDS: Fractures stress, Femoral fractures 相似文献
36.
MA Ebert J Blight S Price A Haworth C Hamilton D Cornes DJ Joseph 《Journal of Medical Imaging and Radiation Oncology》2004,48(3):347-352
Digital data from 3‐D treatment planning computers is generally used for patient planning and then never considered again. However, such data contains enormous quantities of information regarding patient geometries, tissue outlining, treatment approaches and dose distributions. Were such data accessible from planning systems from multiple manufacturers, there would be substantial opportunities for undertaking quality assurance of radiotherapy clinical trials, prospective assessment of trial outcomes and basic treatment planning research and development. The technicalities of data exchange between planning systems are outlined, and previous attempts at producing systems capable of viewing and/or manipulating imaging and radiotherapy digital data reviewed. Development of a software system for enhancing the quality of Australasian clinical trials is proposed. 相似文献
37.
S Bydder NA Spry DRH Christie D Roos BH Burmeister H Krawitz S Davis DJ Joseph M Poulsen M Berry 《Journal of Medical Imaging and Radiation Oncology》2003,47(3):284-288
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation. 相似文献
38.
Measurement of albumin and low molecular weight proteins in the urine of newborn infants using a cotton wool ball collection method 总被引:2,自引:0,他引:2
Objective : The aim of this study was to investigate the inter-relationship between urinary excretion of alpha-1-microglobulin (AIM), retinol-binding protein (RBP) and albumin in term and premature neonates, with urine collected into cotton wool balls and extracted by a novel method. Subjects and methods : Sixty-four infants were studied on the first day of life; 26 had been born at term (37–42 weeks gestation) and 38 prematurely (24–28 weeks n = 16, 29–36 weeks n = 22). Urine collected into cotton wool balls was analysed following a new detergent extraction method, which resulted in a recovery rate of 94–107% for albumin, AIM, RBP and creatinine. Results : Urinary protein excretion, expressed as a ratio to urinary creatinine, decreased significantly with increasing gestational age (24–28 weeks, 29–36 weeks, 37–42 weeks: albuminxreatinine ratio mg/mmol mean 96.9, 31.7, 19.3; AIM: creatinine ratio mg/mmol mean 99.3, 37.0, 7.8; RBP: creatinine ratio mg/mmol mean 16.2, 3.8, and <0.01, below the limit of detection, respectively). When results were corrected for birthweight, this gestation-associated effect was still present for A1M and RBP, but not for albumin. In premature infants there was a significant positive correlation between AIM: creatinine ratio and RBP: creatinine ratio ( r = 0.85), and also between albumin and both AIM and RBP ( r = 0.82 and 0.77). Conclusion : Increased excretion of AIM, RBP and albumin at earlier gestational ages is probably due to proximal tubular immaturity, although tubular damage and also glomerular dysfunction cannot be excluded as possible explanations. 相似文献
39.
Objectives: To assess: (i) the size of placental transfusion following a 30 s delay in cord clamping following vaginal and Caesarean births; and (ii) the feasibility of delaying cord clamping in the labour ward and particularly in the operating theatre.
Methods: Fourty-six infants born at 26–33 weeks gestation were randomized to having the umbilical cord clamped either immediately or 30 s after birth. The venous haematocrit was measured at 1 and at 4 h of age.
Results: There were trends towards higher mean haematocrits in the infants following delayed clamping, but these were not significant either at 1 h (55±7.7 vs 52.9±7) or at 4 h of age (55±7 vs 52.5±7). The trends were more marked in the infants born by Caesarean section, and in those born at 26–29 weeks gestation.
Conclusions: A 30 s delay in cord clamping is feasible at both vaginal and Caesarean births, but does not lead to the predicted difference in infant haematocrit. Although physiological studies suggest that a placental transfusion of 15–20 mL/kg occurs within 30 s of delivery, these data suggest that future trials should either delay cord clamping for more than 30 s, or should alter the position of the infant in relation to the uterus in order to facilitate the transfusion. Delayed cord clamping is feasible at Caesarean section. 相似文献
Methods: Fourty-six infants born at 26–33 weeks gestation were randomized to having the umbilical cord clamped either immediately or 30 s after birth. The venous haematocrit was measured at 1 and at 4 h of age.
Results: There were trends towards higher mean haematocrits in the infants following delayed clamping, but these were not significant either at 1 h (55±7.7 vs 52.9±7) or at 4 h of age (55±7 vs 52.5±7). The trends were more marked in the infants born by Caesarean section, and in those born at 26–29 weeks gestation.
Conclusions: A 30 s delay in cord clamping is feasible at both vaginal and Caesarean births, but does not lead to the predicted difference in infant haematocrit. Although physiological studies suggest that a placental transfusion of 15–20 mL/kg occurs within 30 s of delivery, these data suggest that future trials should either delay cord clamping for more than 30 s, or should alter the position of the infant in relation to the uterus in order to facilitate the transfusion. Delayed cord clamping is feasible at Caesarean section. 相似文献
40.
Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTPw ) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTPw were less likely to have apnoea and/or bradycardia than those given DTPw alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization. 相似文献
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTP
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTP
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization. 相似文献