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1.
All acrocentrics were shown to take part in the formation of satellite association at the 52nd, 72nd and 90th hr of human lymphocytes culturing, in the first mitosis with equal frequency but having different associative capacity in further mitoses. It seems likely that a single nucleolus in the lymphocytes at initial stage of activation, the high frequency of satellite associations, and a random participation of acrocentrics in the associations in first mitosis are due to that all acrocentrics form association in small lymphocytes which are sensitive to PHA.  相似文献   

2.
3.
Meiotic drive has attracted much interest because it concerns the robustness of Mendelian segregation and its genetic and evolutionary stability. We studied chromosomal meiotic drive in the common shrew (Sorex araneus, Insectivora, Mammalia), which exhibits one of the most remarkable chromosomal polymorphisms within mammalian species. The open question of the evolutionary success of metacentric chromosomes (Robertsonian fusions) versus acrocentrics in the common shrew prompted us to test whether a segregation distortion in favor of metacentrics is present in female and/or male meiosis. Performing crosses under controlled laboratory conditions with animals from natural populations, we found a clear trend toward a segregation distortion in favor of metacentrics during male meiosis, two chromosome combinations (gm and jl) being significantly preferred over their acrocentric homologs. Apart for one Robertsonian fusion (hi), this trend was absent in female meiosis. We propose a model based on recombination events between twin acrocentrics to explain the difference in transmission ratios of the same metacentric in different sexes and unequal drive of particular metacentrics in the same sex. Pooled data for female and male meiosis revealed a trend toward stronger segregation distortion for larger metacentrics. This is partially in agreement with the frequency of metacentrics occurring in natural populations of a chromosome race showing a high degree of chromosomal polymorphism.  相似文献   

4.
Summary The pattern of association of acrocentric chromosomes was examined in ten and five carriers of a 15/21 and a 13/14 Robertsonian translocation, respectively, and was compared with that of the same numbers of relatives with normal karyotypes. In the carriers of 15/21 translocation, the number of large associations (involving more than two acrocentrics) and the association frequencies for individual acrocentric chromosomes, were significantly higher than in the control group. The mean number of associations of the single homologs of the translocation chromosomes was much higher than that of the other acrocentrics. In the carriers of 13/14 translocations, only the association frequency for chromosome 13 was higher than in the normal relatives. The uninvolved chromosomes homologous to those involved in translocations showed an insignificant increase in associations in comparison with the other acrocentrics. These results suggest that some mechanism within the cells compensates for the effect of missing acrocentrics or of acrocentrics lacking NORs on the number of associations. The possible relations of this phenomenon to the activity of the nucleolus organizing regions are discussed.  相似文献   

5.
BUdR-Giemsa labeling and satellite association in human leukocytes   总被引:1,自引:0,他引:1  
Bernd Beek 《Human genetics》1981,59(3):240-244
Summary Satellite associations were analysed in differentially stained human leukocyte chromosomes, obtained from four patients with Down's syndrome and four normal probands. A particular type of close association between two acrocentrics, showing a non-random arrangement of sister chromatids in a concordant dark-to-dark and light-to-light alignment, was found to be more common in patients with Down's syndrome compared with the normal controls. Apart from this particular type of association, sister chromatids are randomly arranged in satellite associations between two acrocentrics in both groups of probands. Considerable differences in the mean frequencies of satellite associations between first and second metaphases of the same individual were found in some probands of both groups of individuals. Since a high degree of inter-individual variability in the proliferative response of human leukocytes in culture is well established, the use of BUdR-Giemsa labeling for comparative analysis of satellite association frequencies is suggested.  相似文献   

6.
Summary The inheritance of nucleolus organizer regions (NORs) was investigated by examining the degree of silver-staining in individual acrocentric chromosomes in two successive generations. The study was undertaken in six Down's syndrome children and their respective parents. Quinacrine fluorescent polymorphisms were used to identify individual acrocentrics and to determine which of the child's acrocentrics were informative as to parental homologue of origin. Of the 66 acrocentrics in the six children, 31 were informative. The correlation between the degree of silver-staining in the child's chromosomes and the respective parental chromosomes of origin was highly significant (P<0.001), with a correlation coefficient of 0.90. The results suggest that the degree of Ag-AS staining is characteristic for a particular chromosome and that this characteristic is an inherited property.  相似文献   

7.
The frequency of acrocentric chromosome associations (ACA) in the long-term culture of lymphocytes progressively decreases by 25% (on the average) for one mitotic cycle. As a result proliferous lymphocytes after 3-4 divisions contain either no associations or not more than 2 associating acrocentrics. The diversity of the peripheral blood lymphocytes as to the frequency of ACA in the first mitosis is connected with their different proliferative activity in the organism.  相似文献   

8.
The somatic chromosomes, obtained from short term leukocyte cultures, were studied of four species of the Hylobatidae: Hylobates lar, H. agilis, H. (Nomascus) concolor and Symphalangus syndactylus. In accordance with earlier observations by others, the diploid chromosome numbers were found to be 44 in both Hylobates lar and H. agilis, 52 in H. concolor and 50 in Symphalangus syndactylus. The chromosome associations observed in metaphase spreads are clearly different in the three types of chromosome complements. In Hylobates lar and H. agilis associations are found between both members of the marked chromosome pair. In Symphalangus syndactylus the only two acrocentric elements of the karyo-type, which are of medium size, associate frequently. In H. concolor finally, the members of three pairs of small acrocentrics are involved in chromosome associations. G-banding patterns (obtained by trypsin treatment) showed that in a male individual of this species also the small acrocentric Y chromosome sometimes participates in these associations. The evolutionary aspects of these observations are briefly discussed.  相似文献   

9.
There is a lack of studies that analyze the association between micronutrient-related biomarker status and physical fitness in adolescents. In the present study, biochemical parameters for iron and vitamin status were studied, along with objective measures of physical fitness in healthy male and female European adolescents. One thousand eighty-nine adolescents (580 girls, 12.5-17.5 yr) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study were included. Hierarchical linear models were performed to determine the associations between micronutrient biomarkers and physical fitness. Age, seasonality, latitude, body mass index, menarche (in girls), and physical activity were used as covariates. For cardiorespiratory fitness, concentrations of hemoglobin, retinol, and vitamin C in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with maximal oxygen consumption. For muscular fitness, concentrations of hemoglobin, β-carotene, retinol, and α-tocopherol in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with better performance of the standing long jump test. In summary, concentrations of hemoglobin and most antioxidant vitamins in male adolescents and β-carotene and 25(OH)D in female adolescents were positively associated with cardiorespiratory and muscular fitness, after controlling for relevant confounders. The associations between physical fitness and iron or vitamin status observed in this cross-sectional study in adolescents should be followed up by a study specifically designed to evaluate causal relationships.  相似文献   

10.
In this work we used daily outpatient data from the Landseed Hospital in a heavily industrial area in northern Taiwan to study the associations between daily outpatient visits and air pollution in the context of a heavily polluted atmospheric environment in Chung-Li area during the period 2007–2011. We test the normality of each data set, control for the confounding factors, and calculate correlation coefficient between the outpatient visits and air pollution and meteorology, and use multiple linear regression analysis to seek significance of these associations. Our results show that temperature and relative humidity tend to be negatively associated with respiratory diseases. NO and are two main air pollutants that are positively associated with respiratory diseases, followed by , , , CO, and . Young outpatients (age 0–15 years) are most sensitive to changing air pollution and meteorology factors, followed by the eldest (age 66 years) and age 16–65 years of outpatients. Outpatients for COPD diseases are most sensitive to air pollution and meteorology factors, followed by allergic rhinitis, asthma, and pneumonia diseases. In the context of sex difference to air pollution and meteorological factors, male outpatients are more sensitive than female outpatients in the 16–65 age groups, while female outpatients are more sensitive than male outpatients in the young 0–15 age groups and in the eldest age groups. In total, female outpatients are more sensitive to air pollution and meteorological factors than male outpatients.  相似文献   

11.
Summary A simple and rapid technique is described whereby the nucleolus organizer regions (NORs) of human chromosomes can be differentially stained with silver. This staining is followed by trypsin-Giemsa banding on the same metaphase chromosomes. The metaphases simultaneously exhibit silverstained NORs and G bands, allowing for the unequivocal identification of all chromosomes and greatly facilitating studies involving the NOR-bearing acrocentrics.  相似文献   

12.
Lymphocytes from one normal male and one normal female were labeled with tritiated thymidine to study the autoradiographic patterns of association of acrocentrics, i.e., D and G groups. Association into groups of two and three acrocentrics was found to be random. These results are supported by a random association found in other cell lines studied without autoradiography. These include: normal persons, leukemic cell lines and several other instances where rearrangements of D and G chromosomes have been found.This paper is dedicated with gratitude to my teacher Dr. MiguelJiménez S. This study was supported by funds from the Universidad Nacional Autónoma de México and the Secretaria de Salubridad y Asistencia.  相似文献   

13.
Summary Carbonic anhydrase activity was studied in the quail metanephros by means of histochemical, histophotometrical and biochemical methods. Male and female samples were examined separately in order to show sex-related differences in enzyme activity and localization. The staining patterns revealed differential distribution of reaction product in the different, tubular segments. The initial portion of proximal tubules showed positivity on the brush border in female kidneys only.Extra situ investigations provided further evidence of sexual dimorphism resulting in higher values of enzyme activity for female than for male kidneys.In both sexes, marked staining was detected at the distal tubule level where histophotometric analysis confirmed the highest amount of reaction product. Moreover, the intracellular staining distribution at this site proved to be similar to that observed for mammalian proximal convoluted tubules.In the collecting ducts, a mosaic-like pattern was found with respect to both carbonic anhydrase staining and metachromatic properties.The functional significance of the presence of enzyme in the different renal tubules is discussed by comparison with the mammalian kidney. A model is proposed whereby the distal tubules represent the main sites of urinary acidification and bicarbonate reabsorption.  相似文献   

14.
《Insect Biochemistry》1986,16(5):789-795
Hybridoma antibodies to Drosophila melanogaster soluble yolk proteins (YPs) were developed by both in vivo and in vitro immunizations followed by the fusion of SP2/0-Ag14 cells and splenocytes of BALB/c mice. Rabbit antiserum was made female specific by affinity column with male proteins as ligand. The binding sites of these hybridoma antibodies and rabbit antibodies towards different YP components were identified with a combination of gel electrophoresis, Western blotting and immunohistochemical staining. A double antibody sandwich enzyme-linked immunosorbent assay was developed with monoclonal antibodies from 2 cell lines and alkaline phosphatase labelled rabbit polyclonal antibodies as primary and secondary antibodies respectively. Yolk polypeptide levels in the haemolymph can be monitored in individual insect samples.  相似文献   

15.
Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) was recently identified as the first tissue-specific angiogenic molecule. EG-VEGF (the gene product of PROK-1) appears to be expressed exclusively in steroid-producing organs such as the ovary, testis, adrenals and placenta. Since the human pancreatic cells retain steroidogenic activity, in the present study we ascertained whether this angiogenic factor is expressed in normal pancreas and pancreatic adenocarcinoma. Tissue samples from normal males (n=5), normal females (n=5) and from surgically resected adenocarcinomas (n=2) were processed for RT-PCR and immunohistochemical studies. Results from semi-quantitative analysis by RT-PCR suggest a distinct expression level for EG-VEGF in the different tissue samples. The relative amount of EG-VEGF mRNA in pancreas was more abundant in female adenocarcinoma (0.89) followed by male adenocarcinoma (0.71), than normal female (0.64) and normal male (0.38). The expression of mRNA for EG-VEGF in normal tissue was significantly higher in females than in males. All samples examined showed specific immunostaining for EG-VEGF. In male preparations, the positive labeling was localized predominantly within the pancreatic islets while in female preparations the main staining was detected towards the exocrine portion. Specific immunolabeling was also observed in endothelial cells of pancreatic blood vessels. Our data provide evidence that the human pancreas expresses the EG-VEGF, a highly specific mitogen which regulates proliferation and differentiation of the vascular endothelium. The significance of this finding could be interpreted as either, EG-VEGF is not exclusive of endocrine organs, or the pancreas should be considered as a functional steroidogenic tissue. The extent of the expression of EG-VEGF appears to have a dimorphic pattern in normal and tumoral pancreatic tissue.  相似文献   

16.
Summary The submandibular glands of female mice and the sublingual and parotid glands of adult male and female mice have been examined by light microscopical immunocytochemistry for nerve growth factor (NGF). In female submandibular glands, staining for NGF was observed in granular convoluted tubule and striated duct cells. Sublingual glands of the mouse contained relatively few granular cells staining for NGF compared with submandibular glands. However, such granular cells appeared to be more numerous in male sublingual glands than in female glands. The remainder of the intralobular duct cells in both male and female sublingual glands exhibited apical subluminal staining for NGF as well as light basal plasmalemmal staining. Parotid glands in both male and female mice exhibited a similar pattern of staining for NGF in striated duct cells. However, the glands did not contain granular cells nor did they exhibit any pattern of staining which reflected a sexual dimorphism. Immunodot staining of salivary gland extracts confirmed the presence of immunoreactivity for NGF in all three of the major salivary glands.  相似文献   

17.
Summary Peripheral blood cultures of five healthy chromosomally normal adults were used to study the lateral orientation of mitotic chromatids in satellite associations. Chromosomes were prepared after bromodeoxyuridine substitution for two S phases and the fluorescence-plus-Giemsa (FPG) technique. Conventionally stained preparations were used to assess the polymorphisms of the acrocentrics in each individual. Satellite association pairs in which the acrocentrics were involved in a close, relatively straight end-to-end configuration were analyzed in cells with differentially stained sister chromatids. The number of concordant (light-light) and discordant (light-dark) chromatid alignments in associations varied from individual to individual. Chi square analysis revealed that four of the five subjects and the combined cell population from all subjects showed no deviation from the expected frequency of random alignment. The one subject with preferential nonrandom alignment had the widest range of polymorphisms and very long stalks involved in the majority of the associations, compared with the rest. We have obtained no evidence that as a general rule satellite associations are nonrandom with preferential orientation of dark-to-dark and light-to-light chromatids, although this may be the case in some individuals with very active NORs.  相似文献   

18.
In 46 male and 19 female students who were both donors and recipients of scent samples, we studied effects of the menstrual cycle phase, reproductive health, sexual motivation, and sexual experience on subjective assessment of intensity and pleasantness of the sweat scent. The sweat samples were collected by the 60-min long exposure of a filter paper in the armpit. Then the male and female samples were reciprocally assessed olfactorily with respect to their intensity, unpleasantness/pleasantness, and association with male or female. It has been established that the cycle phase affects statistically significantly the coincidence of subjective assessments by the unpleasant/pleasant scale, which different recipients were giving to the same scent samples. Their coincidence in the non-receptive state is replaced by the non-coincidence at the receptive cycle phase, which indicates an increase in the contribution of the recipient's individual properties to the variability of scent assessments. In girls in the non-receptive state there is noted the reverse correlation between the strength and pleasantness of the male scent. In the receptive state, they become tolerant to intensive male scents. At non-regular menstrual cycles, the female scent is assessments by young males as less pleasant. At the same time, the girls themselves with the cycle disturbances assess higher the male scent samples as compared with reproducibly healthy girls. The first sexual experience decreases the subjective assessments given by girls to the male scent samples. The young males, on the contrary, increase assessments given by girls to the male scent samples. The young males, on the contrary, increase assessments of the female scent on having acquired the sexual experiment. Coefficients of correlation of the mutual assessments of scent pleasantness of young males and females are progressingly rising with increase of biological and social significance of the search for optimal partner. Thus, effect of psychophysiological and social factors on assessments of pleasantness of scent samples aggress well with requirements, to which the reproductively significant non-verbal signal should fit.  相似文献   

19.
Summary Trypsin-banded metaphase plates provided by one whole blood culture of a normal adult female were analyzed as to the chromosome distribution by measuring: (1) distances between centromeres; (2) angles formed between a centromere, the gravity center of the metaphase plane, and a second centromere; and (3) the measured tendency to associate, as defined by Galperin (1969b). These data are correlated with Ag-NOR staining findings obtained from 72 cells from another culture of the same individual. In these cells, the chromosome pairs are identified using a simultaneous Ag-NOR staining and acridine orange banding technique. The silver precipitation is also correlated with the scored satellite associations in these cells. The results show a correlation between all concerned parameters, indicating that the nucleolar function of the human acrocentric chromosomes, as demonstrated by the silver precipitation technique, is probably one of the major determinants of the proximity of these chromosomes. There is a pronounced correlation of the Ag-NOR findings with those measured parameters which describe best the preferential small distances between chromosomes (angle analysis and tendency to associated data). Moreover, the association patterns of the acrocentrics with small amounts of NOR provide some evidence for the interference of other determinants cogoverning the position of the human D-and G-group chromosomes.To whom offprint requests should be sent  相似文献   

20.
Summary Nerve growth factor (NGF) was localized in the submandibular, sublingual, and parotid salivary glands of male and female diabetic mice and their normal littermates by immunoperoxidase staining usingp-phenylenediamine-pyrocatechol as a chromogen for the cytochemical demonstration of peroxidase activity. In the normal male submandibular gland, immunoreactive NGF was localized in the apical regions of granular, intercalated and collecting duct cells, while in the normal female submandibular gland, NGF was present throughout the cytoplasm of granular duct cells. The localization of NGF in the diabetic male and female submandibular glands was similar and resembled that of the normal female. NGF immunoreactivity was also observed in the striated duct cells in the sublingual and parotid glands of all four types of mice.The sympathetic innervation of the submandibular glands of normal and diabetic mice was demonstrated using glyoxylic acid-induced histofluorescence. The pattern of sympathetic innervation and the intensity of catecholamine fluorescence was consistently different in the four types of mice. In the normal male submandibular gland the fluorescence was very intense, particularly in nerves adjacent to the granular ducts. In the normal female submandibular gland, the fluorescence was weak, while in the diabetic male and female the fluorescence was moderate.The correlation between the intensity of the immunocytochemical staining for NGF and the catecholamine fluorescence adjacent to the granular ducts suggests a trophic influence of the NGF-containing granular ducts on their sympathetic innervation.  相似文献   

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