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1.
Although clinical features in Turner syndrome have been well defined, underlying genetic factors have not been clarified. To deduce the factors leading to the development of clinical features, we took the following four steps: (1) assessment of clinical features in classic 45,X Turner syndrome; (2) review of clinical features in various female sex chromosome aberrations (karyotype-phenotype correlations); (3) assessment of factors that could lead to Turner features; and (4) correlation of the clinical features with the effects of specific factors. The results indicate that the clinical features in 45,X and in other female sex chromosome aberrations may primarily be determined by: (1) degree of global non-specific developmental defects caused by quantitative alteration of a euchromatic or noninactivated region; (2) dosage effect of a pseudoautosomal growth gene(s), a Y-specific growth gene(s), and an Xp-Yp homologous lymphogenic gene(s); and (3) degree of chromosome pairing failure in meiocytes that are destined to develop as oocytes in the absence of SRY.  相似文献   

2.
目的用生长激素与促性腺激素释放激素类似物(Gonadotropin-releasing hormone analogues,GHA)联合治疗中枢性性早熟女性患儿对其最终成人身高的影响.方法生长激素(GH)与促性腺激素释放激素类似物(GHA)联合治疗4例中枢性性早熟女性患儿半年,对比治疗前后患儿的第二性征,骨龄发育,性激素及最终成人身高的变化.结果第二性征的发育停止,骨龄发育被控制,实际生活年龄与骨年龄的比值提高(平均0.79→0.84);血LH对促性腺激素释放激素的反应及血浆雌激素水平平均已降至青春期前,分别为(平均25.79±10.60mlu/ml→1.13±0.21mlu/ml)及(平均64.87±27.51pg/ml→3.03±1.87pg/ml);预测最终成人身高增加(平均149.60±4.31cm→156.75±3.84cm)差异具有显著性(P<0.05).结论生长激素与GHA联合治疗中枢性性早熟患儿,不仅能抑制第二性征发育,而且能有效改善最终成人身高,无任何毒付作用.  相似文献   

3.
Studies on tooth crown size and structure of individuals with various sex chromosome anomalies and their normal male and female relatives have demonstrated differential direct effects on growth of genes on the human X and Y chromosomes. The Y chromosome promotes growth of both tooth enamel and dentin, whereas the effect of the X chromosome on tooth growth seems to be restricted to enamel formation. Enamel growth is decisively influenced by cell secretory function and dentin growth by cell proliferation. It is suggested that these differential effects of the X and Y chromosomes on growth explain the expression of sexual dimorphism in various somatic features, such as the size, shape and number of teeth, and, under the assumption of genetic pleiotropy, torus mandibularis, statural growth, and sex ratio. Future questions concern, among other topics, the Y chromosome and the mineralization process, concentric control of enamel and dentin growth, and gene expression. Received: 11 March 1997 / Accepted: 10 June 1997  相似文献   

4.
Summary Sister chromatid exchanges (SCE) and structural chromosome aberrations were analyzed in peripheral blood lymphocytes of 100 individuals, and correlated to age and sex. No correlation was found between the frequency of SCE and age, but older individuals had significantly more structural aberrations than younger. Females had significantly more SCE as well as structural chromosome aberrations than males. The positive correlations of SCE and structural aberrations to age and sex were also significant when these factors, as well as smoking habits, were taken into consideration in an analysis of covariance.  相似文献   

5.
The statural catch-up growth, defined as reaching at least tenth length/height percentile (P10) for normal population standards (-1.28 SD score, SDS), was studied in 73 infants short at birth (length < P10 for gestational age) admitted to NICU. Mean gestational age at birth was 35.2 weeks (range 29-41) and mean birth length standard deviation score -2.31 (-4.52/-1.46). Infants were measured at birth, at 3, 6, 12, 18, and 24 months corrected age and then once a year until 6 years chronological age. Statural catch-up growth was studied, with reference both to normal population standards and to individual genetic target. With reference to normal population standards, 44% of infants had caught-up at 3 months of age, 51% at 3 years, 66% at 4 years and 73% at 6 years. In the case of individual genetic targets, a similar trend was present, but the absolute values were slightly higher from 4 to 6 years (73 vs. 66% and 78 vs. 73%, respectively). Statistically significant changes in mean standard deviations score for chronological age were present from birth to 3 months, 3 to 12 months, 3 to 4 years and 5 to 6 years (p<0.05). No differences were found in this trend of recovery when considering ponderal index (PI) at birth (symmetrical vs. asymmetrical), sex (male vs. female) or gestational age (p>0.05). In the majority of cases infants with short stature at birth admitted to a NICU had a statural catch-up growth within the first years of life. This is more evident when considered in relation to individual genetic target rather than to normal population standards.  相似文献   

6.
Previous studies in animal populations have shown that stunted neural and thymolymphatic growth early in development may result in permanently impaired neural and immune function, decreased body growth, vertebral wedging, and decreased life-span. In the human adult, small vertebral neural canal (VNC) diameters may reflect early stunted neural and immune development and impaired function that leads to decreased health (inferred by greater vertebral wedging) and life-span in the adult. VNC, which complete their growth by early childhood (age 4), are markers of early development in adults. On the other hand, features following general body growth, such as height, weight (represented here by vertebral body height) continues to grow until young adulthood. They are less reliable, because they readily experience catch-up growth (even in chronically stressed populations) and, unlike VNC, may mask poor early growth. To test associations between early growth and adult health and life-span in humans, we measured 2,060 VNC, vertebral heights, vertebral wedging, nerve-root tunnel lengths, severity of vertebral osteophytosis, and ages at death in 90 adult (aged 15-55 years) prehistoric skeletons (950-1300 A.D.). Tibial lengths were also measured in a subsample (n = 30). Multivariate, bivariate, and nonparametric analyses showed that small VNC are significantly associated with greater vertebral wedging and decreased life-span (P less than 0.05-0.00001). VNC are independent of vertebral body heights and tibial lengths (general body growth). VNC, but not statural components, are useful in predicting adult health, presumably because they reflect neural and immune development and do not readily experience catch-up growth. Thus, longitudinal retrospective measures of early growth and adult health were systematically linked within individuals regardless of confounding factors operating over the 350-year time period. Since this research was completed, this model has repeatedly been independently confirmed in four living urban industrial populations. Longitudinal retrospective analysis was employed together with direct measures of VNC, neural and immune function. Together these results suggested that it may be essential to improve growth prior to early childhood in order to maximize adult health and life-span.  相似文献   

7.
对217例无精和严重少精症患者外周血淋巴细胞染色体核型进行分析,并采用聚合酶链反应对7例Y染色体结构异常患者的AZFc区进行检测。发现187例无精症患者中检出异常核型77例(41.18%)(其中46,XY,t(6;14)(p21;p13),46,XY,t(8;12)(p21;q24)为世界首报核型),主要涉及染色体异常(数目异常和结构异常);染色体异态(Y染色体异态和9号染色体臂间倒位)及46,XX性反转;30例严重少精症患者中检出异常核型4例(13.33%)(结构异常和46,XX性反转)。由此可见,性染色体数目和结构异常是精子发生障碍的主要原因,其次常染色体的某些断裂点也可能影响精子发生。AZFc区的缺失与否与精子发生也有直接关系。  相似文献   

8.
Screening human populations for chromosome aberrations   总被引:2,自引:0,他引:2  
A Norman  D Bass  D Roe 《Mutation research》1985,143(3):155-160
In order to determine the usefulness of micronuclear counts (MNC) for identifying people with relatively high frequencies of chromosome aberrations we have examined factors that influence the MNC in a learning set of blood samples obtained from 28 adults. The presence of cells with chromosome aberrations among approximately 170 metaphase cells per sample was the most important factor. Controlling for the effect of chromosome aberrations we found that age had a significant effect on MNC, but that donor sex, the mitotic index, the per cent of metaphase cells in the second or third division or the frequency of abnormal anaphase cells did not. Using logistic regression analysis we found that MNC was an excellent predictor of the presence of cells with chromosome aberrations among both the learning set and a test set of 17 additional blood samples.  相似文献   

9.
Several methodological problems complicate the evaluation of final statural height (FH) benefit after treatment with gonadotropin releasing hormone (GnRH) agonists for central precocious puberty (CPP). Since no controlled study has been performed, we have to rely on indirect methods, comparison with predicted height or with historical controls. FH of 58 girls, uniformly treated with triptorelin slow release formulation (triptorelin-SR, Decapeptyl((R))) for CPP were compared with predicted height before treatment and with FH of an historical group of patients not treated with GnRH agonist. The comparison with predicted height revealed an improvement of 4.8 +/- 5.8 cm; comparison with the historical control group showed a mean improvement of 8.3 cm. The post-treatment growth spurt (DeltaFH - height at the end of treatment) was a strong predictor of FH in multivariate analysis. The data suggest that continuing treatment beyond the age of 11 in girls does not improve and could actually decrease FH.  相似文献   

10.
In boys with constitutional delay of growth and puberty, adult height may be inconsistent with parental (target) height. We aimed at studying which period of growth was important to account for adult height being above or below target height. In this retrospective study, adult height measured after 20 years in 39 patients was compared with target height and height data obtained at about 6 and 12 years of age and at diagnosis of delayed puberty (mean 14.6 years). Twenty-eight patients were untreated while 11 received testosterone enanthate (50 or 100 mg/month for 6 months). The growth data from both groups were pooled since they were not different. On average, the adult height standard deviation score (-0. 6 +/- 0.8, mean +/- SD) was similar to target height (-0.5 +/- 0.6). There were, however, marked individual differences since adult height varied between 1.7 SD (11 cm) below target height and 1.4 SD (9.5 cm) above target height. Multiple regression analysis showed that the most significant determinant of the difference between adult height and target height was height catch up during puberty (p < 0.002). We conclude that the magnitude of height catch up during puberty is a significant determinant of adult height in boys with constitutional delay of growth and puberty. Thus, optimizing pubertal growth may be a relevant therapeutic aim for adult height in boys with short stature and delayed puberty. Copyrightz1999S. KargerAG,Basel  相似文献   

11.
Fluorescence in situ hybridization (FISH) was used to compare aneuploidy rates in four autosomes and two sex chromosomes in interphase nuclei of noncultivated (quiescent) and cultivated (induced to divide with phytohemagglutinin (PHA)) leukocytes in people engaged in nuclear-chemical industry and in a control group of people not exposed to mutagenic factors occupationally or at home. The overall rates of numerical chromosome aberrations for all of the six chromosomes studied showed little difference, although a higher rate of loss of the X- and Y-chromosomes was observed in the exposed group. In individuals exposed to several adverse environmental factors, the overall rate of numerical chromosome aberrations in cultivated cells after at least one DNA replication cycle exceeded that in noncultivated cells by 52% (P = 0.01), whereas only a trend for its increase was observed in the control group (23%, P = 0.25). Thus, the effect of adverse environmental factors in humans caused more than a twofold increase in the difference between the rates of aneuploid cells in cultivated and non-cultivated leukocytes in the exposed group as compared to control. It is conjectured that cell division is accompanied by the expression of potential damage of mitotic chromatid segregation apparatus accumulated in vivo. These defects, realized during cell division, bring about numerical chromosome aberrations.  相似文献   

12.
Blood samples were taken from 106 individuals (73 males and 33 females) and examined for chromosome aberrations, mitogen-induced blastogenesis and proliferative rate index (PRI). The values obtained were investigated in relation to sex, age, smoking, alcohol consumption and X-ray exposure. In all the parameters, there was shown to be a difference between the mean values for the males and females. The incidence of chromosome aberrations was greater in females than in the males, whereas the mean values of PRI and mitogen-induced blastogenesis were lower in females than in the males. A sex difference has been reported previously in the same population, in that the females were shown to have a higher rate of sister-chromatid exchanges than the males (Anderson et al., 1986; Dewdney et al., 1986). Contraceptive pill usage was not considered to be of importance in the sex difference seen and there was shown to be no significant influence due to age, smoking or alcohol consumption on any of the parameters except that smoking reduced lymphocyte PRI. Males with previous X-ray exposure also showed a lower response to mitogen-induced blastogenesis and had a reduced PRI.  相似文献   

13.
This study reviews the frequency and distribution of numerical and structural chromosomal abnormalities in spermatozoa from normal men obtained by the human-hamster system and by multicolor-FISH analysis on decondensed sperm nuclei. Results from large sperm karyotyping series analyzed by chromosome banding techniques and results from multicolor FISH in sperm nuclei (of at least 10(4) spermatozoa per donor and per probe) were reviewed in order to establish baseline values of the sperm chromosome abnormalities in normal men. In karyotyping studies, the mean disomy frequency in human sperm is 0.03% for each of the autosomes, and 0.11% for the sex chromosomes, lower than those reported in sperm nuclei by FISH studies using a similar methodology (0.09% and 0.26%, respectively). Both types of studies coincide in that chromosome 21 and sex chromosomes have a greater tendency to suffer segregation errors than the rest of the autosomes. The mean incidence of diploidy, only available from multicolor FISH in sperm nuclei, is 0.19%. Inter-donor differences observed for disomy and diploidy frequencies among FISH studies of decondensed sperm nuclei using a similar methodology could reflect real differences among normal men, but they could also reflect the subjective application of the scoring criteria among laboratories. The mean frequency of structural aberrations in sperm karyotypes is 6.6%, including all chromosome types of abnormalities. Chromosome 9 shows a high susceptibility to be broken and 50% of the breakpoints are located in 9q, between the centromere and the 9qh+ region. Structural chromosome aberrations for chromosomes 1 and 9 have also been analyzed in human sperm nuclei by multicolor FISH. Unfortunately, this assay does not allow to determine the specific type of structural aberrations observed in sperm nuclei. An association between advancing donor age and increased frequency of numerical and structural chromosome abnormalities has been reported in spermatozoa of normal men.  相似文献   

14.
Summary The frequency of chemical diabetes is increased in patients with aneuploid sex chromosome aberrations such as Klinefelter's syndrome and Turner's syndrome, and a high frequency of chemical diabetes has been found in parents of patients with Down's syndrome. Abnormal pattern in plasma insulin and growth hormone during a glucose load has been found in patients with Klinefelter's syndrome and Turner's syndrome.These findings might, if they are confirmed on large and well selected groups of patients with different chromosome abnormalities, shed some new light on the genetic background of diabetes mellitus, i.e. on the role of the sex chromosomes in the aetiology of diabetes mellitus or alternatively on the possibility that the frequency of non-disjunction in increased in patients with diabetes mellitus.  相似文献   

15.
The aim of the study was to investigate the effects of the Y chromosome on different body and head dimensions of 47,XYY males, and especially its effect on their body proportions. From seven adult 47,XYY males 25 anthropometric measurements were recorded and compared with four male relatives and 42 control males. In most dimensions 47,XYY males were larger than the normal males, the difference being mainly between 0.5 and 1.5 S.D. units. The body proportions of 47,XYY males were found to be similar to those of the normal males when the effect of size was allowed for. It is concluded that the extra Y chromosome in 47,XYY males causes an increase in their growth without affecting the body proportions. This finding suggests that the Y chromosome contains gene(s) which affects growth by increasing its quantitative outcome. This effect may be mediated by a direct action of the Y chromosome on the cells. It also may seem that the Y chromosomal gene(s) influence the development of the sex difference in height and body size.  相似文献   

16.
Sex differences in growth were studied in a longitudinal study of 39 boys and 31 girls for sitting height. Individual growth patterns were determined by means of Preece Baines model 1. The results showed no significant bias in the fits of height and sitting height in boys and girls. Girls fits were significantly better than those of the boys for both height and sitting height. Univariate analysis by means of Mann-Whitney test showed significant sex differences for all function and biological parameters of height and sitting height excepted for s1 parameter (the rate constant controlling pubertal velocity). Linear discriminant analysis revealed that the strongest sex differences for the timing and size parameters at adolescent. Peak velocity at adolescent was slightly less discriminating between the two sexes and velocity at take-off showed the least sex difference. These trends were similar for height and sitting height. Decomposition of sex differences in adult size showed that the major contributor to adult the sex differences is the effect of the later onset of the adolescent growth spurt in boys than in girls. Sex differences in adult phenotypes of height and sitting height are to a slightly lesser extent due to the greater adolescent gain in boys while prepubertal sex differences are almost negligible.  相似文献   

17.
目的:通过荧光原位杂交技术(FISH)结合病理分级,探讨染色体畸形变与膀胱癌发生和发展的关系。方法:采用3、7、9、17号染色体着丝粒探针和9P16区带探针对105例膀胱癌复发患者尿液脱落细胞进行荧光原位杂交,观察膀胱癌复发患者中3、7、9、17号染色体的畸形变情况并分析其与患者临床和病理特征之间的关系。结果:105例膀胱癌复发患者中,3、7、9和17号染色体的非整数倍突变率分别是21.9%、29.5%、12.4%、和36.2%,与患者的性别、年龄无显著相关性(P0.05)。仅7号染色体畸变与膀胱癌的病理分级具有显著相关性(P0.05)。结论:7号染色体畸形变与复发膀胱癌的病理分级显著相关。  相似文献   

18.
Chromosome studies were carried out on peripheral blood lymphocytes from 36 PCB-poisoned patients and on ten PCB-unexposed healthy controls. Nineteen out of 36 patients (52.7%) had either chromosome or chromatid aberrations, while none of the controls had. The highest percentage of cells with chromosome or chromatid aberrations in a single individual was 34.0. The blood PCB level ranged from 6.4 to 101.8 ppb, with a mean of 34.1 ppb. No correlation was observed between the level of blood PCB and the presence or absence of chromosome or chromatid aberrations.  相似文献   

19.
Childhood celiac disease may lead to a failure of statural growth. After institution of a gluten-free diet most patients exhibit catch-up growth. Catch-up growth is a remarkable phenomenon characterized by a supranormal height velocity. One of the hypothetical mechanisms of catch-up growth is that an increased activity of the somatotrophic axis is involved. In order to provide further insight in the physiology of catch-up growth, auxological and endocrine changes were prospectively studied in 28 children with newly diagnosed celiac disease. The results demonstrate a malnutrition-like state of the somatotrophic axis at the time of diagnosis and a rapid recovery of this axis towards normal functioning after institution of the gluten-free diet. Although several correlations between these endocrine alterations and auxological parameters were detected, it is questionable whether the endocrine changes are the driving force behind catch-up growth.  相似文献   

20.
Summary Chromosome aberrations were studied in peripheral lymphocytes from 50 patients treated with melphalan against ovarian carcinoma. The chromosome analyses were carried out 4–132 months (mean 57 months) after the end of melphalan therapy. Most of the patients were studied several times during four years. The mean frequency of cells with chromosome and chromatid aberrations was 5.4% in the patients and 2.3% in an untreated control group. The highest aberration frequency (average 18%) was found in a patient who later developed gastric carcinoma. The dominating types of berrations in the patients were chromosome exchanges occurring as single marker chromosomes or as multiple chromosome rearrangements. These types of aberrations were found in only 0.3% of the control cells as compared to 3.8% of the patient cells. Patients with a high total dose of melphalan (above 420 mg) and a long duration of the therapy (average 22.5 months) had a higher frequency of cells with aberrations (6.3%) than patients with a lower total dose (below 420 mg) and a shorter therapy (12 months) (4.2%). No additive effect of radiation therapy was observed on the aberration frequency.This work was supported by grants from the Swedish Cancer Society (1179), and the Swedish Medical Research Council (3681)  相似文献   

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