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1.
An increase in the nuchal translucency that can be detected at 10-14 weeks of gestation by ultrasound forms the basis for a screening test for chromosomal abnormality. Several mechanisms leading to this increase in skin thickness have been proposed, including changes of the extracellular matrix, cardiac defects and abnormalities of the large vessels. This study examines the composition of the extracellular matrix of the skin in gestational age-matched fetuses with trisomy 21, 18 and 13 from 12-18 weeks. Immunohistochemistry was applied with monoclonal and polyclonal antibodies against collagen type I, III, IV, V and VI and against laminin and fibronectin. Collagen type VI gene expression was further studied by in situ hybridization to detect differences in expression patterns of COL6A1, COL6A3 and COL1A1 between normal fetuses and those with trisomy 21. The ultrastructure of tissue samples was studied by transmission electron microscopy (TEM) and additionally by immunogold TEM. Further, we examined the morphology of the skin in an animal model for Down's syndrome, the murine trisomy 16, by light and TEM. The dermis of trisomy 21 fetuses was richer in collagen type VI than that of normal fetuses and other trisomies, and COL6A1, located on chromosome 21, was expressed in a wider area than COL6A3, which is located on chromosome 2. Collagen type I was less abundant in the skin of trisomy 18 fetuses, while the skin of all three trisomies contained a dense network of collagen type III and V in comparison with normal fetuses. Collagen type IV, of which two genes are located on chromosome 13, was expressed in the basement membranes of the skin in all fetuses and additionally in the dermal fibroblasts only of trisomy 13 fetuses. Likewise, laminin was present in all basement membranes of normal and trisomic fetuses as well as in dermal fibroblasts of fetuses with trisomy 18. LAMA1 and LAMA3 genes are located on chromosome 18. Dermal cysts were found in the skin of trisomy 18 and 13, but not in trisomy 21 and normal fetuses. Ultrastructural findings showed that an extracellular precipitate containing glycosaminoglycans was regularly present in the skin of trisomy 21 fetuses and murine trisomy 16 embryos. In conclusion, this study suggests that the skin edema in fetal trisomies is characterized by specific alterations of the extracellular matrix that may be attributed to gene dosage effects as a result of a genetic imbalance due to the condition of fetal trisomy.  相似文献   

2.
Fourteen members of family P. and four members of family N. were clinico-biochemically examined. Among twelve adult children (19-32 years old) of family P. five sons manifested angiokeratotic skin lesions and other clinical signs of Fabry disease. Three of the probands had additional symptoms not generally found in Fabry disease. Biochemical studies including an enzyme assay, analysis of storage products and alpha-galactosidase multiple forms, allowed us to confirm the diagnosis of Fabry disease in four affected brothers and to establish the heterozygous status of their mother. The data of biochemical investigation of patient N. with atypical variant of Fabry disease are also presented. The patient N. with strong skin lesions had a high residual alpha-galactosidase activity and unusual composition of alpha-galactosidase multiple forms.  相似文献   

3.
Excessive deposition of extracellular matrix or neomatrix is a characteristic of desmoplastic invasive breast carcinomas. Type I and III collagens are abundant neomatrix components. Archival breast tissue sections were studied using 35S-labeled cDNA probes for alpha 1(I) and alpha 1(III) procollagen and in situ hybridization. Among the 33 invasive breast cancers, hybridization was seen forming a gradient-like pattern in fibroblasts closest to tumor cells. In the 10 ductal carcinomas in situ studied, a ring-like pattern of hybridization was seen in proximity to the basement membrane zone. Adjacent normal and benign tissues did not demonstrate the patterns of hybridization described in malignant tissues. Gene expression for neomatrix interstitial collagens occurs before there is evidence of invasion in carcinoma of the breast.  相似文献   

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Twenty-eight individuals with typical Down's syndrome (DS) phenotype (17 males and 11 females; age range: 10-74 years) were investigated for gender differences in the phenotypic expression of Alzheimer-type pathology (ATP). Quantitative neuropathology was performed in the 4 neocortical lobes of the right hemisphere, by counting senile plaques (SP), and neurofibrillary tangles (NFT). ATP was present in 25 middle-aged (> 40 years) individuals (16 males and 9 females). Females had significantly higher (p = 0.03) mean neocortical NFT densities (36.6 per mm2; s.e.m. +/- 6.6) than males (17.9 per mm2; s.e.m. +/- 4.7). None of the females had NFT densities below 10 per mm2, compared with 6 males in whom NFT were either absent or seen in very low densities (< 4 per mm2). Assessment of SP densities in the same cortical regions showed non-significant differences in females (42.4 per mm2; s.e.m. +/- 5.1) compared with males (33.6 per mm2; s.e.m. +/- 2.1). There was clinical evidence of dementia in all the female (8/8) individuals who were prospectively assessed, compared with only 54% (7/13) of males. The male individuals without clinical dementia had absent or low neocortical NFT densities regardless of high SP densities. Female DS cases (mean age: 48.8 years; s.e.m. +/- 1.9) had an earlier onset of dementia than males (mean age: 53.6 years; s.e.m. +/- 1.3; p = 0.05). Female middle-aged DS individuals have an earlier onset, and a more severe form of AD which correlates with higher neocortical NFT rather than SP density.  相似文献   

6.
Cytogenetic findings and fluorescens in situ hybridization results of a hepatoblastoma of a boy of two and half years of age are presented. Cytogenetic analysis and fluorescens in situ hybridization technique were performed using tumor tissue obtained by biopsy. The direct culture was harvested after 16 hour colcemid treatment. The results of G-banding were as follows: 47,XY,add(4) (q26),-9,+20. There were considerable variation in the degree of condensation and hence in the number of visible G-bands both between metaphases and between homologous chromosomes in the same metaphases. Fluorescens in situ hybridisation were carried out by whole chromosome painting probes: 2,3,4, and 20. The karyotype of the malignant cells was adjusted accordingly: 47,XY,der(4)(q35),dir ins(9;2)(p22;q?21q?25),+20. The results confirm the most common primary chromosome abnormalities in hepatoblastoma are the following: trisomy 2, trisomy 20 and 4q structural rearrangement. Fluorescens in situ hybridization confirms the importance of trisomy 2q21-qter in hepatoblastoma. Authors recommend the use of fluorescens in situ hybridization to correct any tumor karyotype with difficult or ambiguous chromosome morphology.  相似文献   

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A newborn infant with trisomy 21 was found to have congenital diabetes which appears to be permanent. Congenital diabetes is extremely rare and differs from type I or type II diabetes. It has never been reported previously in Down's syndrome and it seems to be due to a selective beta cell defect with undetectable C-peptide but normal alpha-cell function.  相似文献   

9.
The major histological characteristic of sun-damaged skin is the accumulation of an elastotic material that appears to replace collagen. This elastotic material consists primarily of elastin and histological studies suggest a large loss of collagen in the dermis of chronically sun-damaged skin. In this study, we examine the content and distribution of collagen and procollagen in sun-damaged human skin. The total collagen content of sun-damaged skin was 20% less than nonsolar-exposed skin (524 micrograms collagen per mg total protein in sun-damaged skin and 667 micrograms collagen per mg total protein in nonsolar-exposed skin). In addition, there was a 40% decrease in the content of intact amino propeptide moiety of type III procollagen in sun-damaged skin (0.68 U per 50 mg wet weight) as compared to nonsolar-exposed skin (1.12 U per 50 mg wet weight). The data suggest that this change in collagen content is due to increased degradation. The distribution of collagen in sun-damaged skin was examined by indirect immunofluorescence. Mild digestion of sun-damaged skin with elastase removed the elastin and revealed the presence of collagen in the elastotic material. Therefore, the elastin appears to mask the presence of collagen fibers in the dermis of sun-damaged skin.  相似文献   

10.
Secondary vitamin K deficiency in rats caused by pelentan was accompanied by a decrease in the total collagen content and a rise in free oxyproline in the skin. Under these conditions the rate of collagen hydrolysis proved to increase. Vitamin K (vikasol) prevented development of the mentioned shifts in collagen metabolism.  相似文献   

11.
We report for the first time the case of postabortional HELLP-syndrome in the 21st week of gestation. In this case mosaic trisomy 9 was confirmed by amniocentesis prior to induction. Pertinent history, clinical course and pathoanatomical morphology are described. We emphasize the early onset of the HELLP-syndrome in association with trisomy 9 after abortion. The possibility of interconnections between trisomy 9 and the occurrence of HELLP-syndrome (sparse blood, vessels in the villi, circulatory deficit on the fetal side of the placenta, increased production of e.g. vasopressive substances) is discussed.  相似文献   

12.
In approximately 5% of individuals with Down syndrome aneuploidy results from a chromosomal rearrangement. FISH analysis on chromosome metaphases and interphase nuclei of 5 individuals with Down syndrome carrying different types of chromosome 21 translocations demonstrated the diagnostic efficiency of this method. By use of different commercially available chromosome 21 specific probes we were able to show that only the cosmid probe specific for the Down syndrome critical region (DCR) in 22qll gave reliable results for interphase analysis of trisomy 21, while the use of chromosome 21 centromere- or of painting probes carry a high risk of a false-negative diagnosis in translocation trisomy 21.  相似文献   

13.
Beliefs about human nature, adult education, adult learners, and moral commitment are at the heart of the educator-learner agreement. In continuing nursing education, it is the point where professional values, morals, and ethical principles meet. Using Husteds' bioethical decision-making model, the values, beliefs, and actions within the educator-learning agreement are identified and organized by the bioethical standards. By relating the bioethical standards to practice, continuing nurse educators can find their own basis for practice and work toward attaining a consistent professional ethical orientation.  相似文献   

14.
Using biochemical and immunocytochemical methods, we have investigated endogenous levels of various markers in tissues obtained from 67 Down's syndrome pregnancies after therapeutic abortion in the second trimester and in corresponding tissues from unaffected abortuses. Alpha-fetoprotein (AFP), intact and free beta human chorionic gonadotrophin (hCG), pregnancy-specific beta-1 glycoprotein (SP-1), placental alkaline phosphatase (PALP), pregnancy-associated plasma protein A (PAPP-A), and gamma glutamyl transferase (GGT) were investigated in placental tissue; AFP and GGT in fetal liver; and GGT in fetal intestine. The results indicate that maternal serum levels of placental products reflect those found in the placenta: intact hCG, free beta hCG, and SP-1 levels were elevated in Down's syndrome pregnancies, while PAPP-A and PALP levels were little changed. This suggests that membrane passage of these markers is not affected but there is altered synthesis of hCG and SP-1. AFP levels were strikingly elevated in placental homogenates and unchanged in liver homogenates from Down's syndrome pregnancies, while the levels in maternal serum were reduced, pointing to a possible transport defect specific to AFP. GGT levels were high in placenta and liver from Down's syndrome pregnancies but low in fetal intestine.  相似文献   

15.
We describe a novel phage display system that affords the surface expression and hence affinity selection of cDNAs. The strategy is based on a new approach to functionally display proteins on filamentous phage through the attachment to the C-terminus of the minor coat protein VI. The utility of the method was evaluated using a cDNA library derived from the parasite Ancylostoma caninum. cDNA sequences were fused in each of the three reading frames to the 3'-end of the M13 gene VI expressed by a phagemid vector. Phages rescued from this cDNA expression library were subjected to biopanning against two serine proteases, trypsin and the human coagulation factor Xa. This led to the identification of cDNAs encoding novel members of two different families of serine protease inhibitors. The authenticity of the cDNA selected with trypsin as the target was demonstrated by purifying the encoded potent Kunitz-type inhibitor from an Ancylostoma caninum extract. The rapid isolation of specific cDNAs with the protein VI monovalent display system should facilitate the search for novel biologically important ligands.  相似文献   

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A new instrument for laparoscopic access consists of a trocarless, reusable, visual-access cannula with an external thread that ends in a blunt tip. The device has no sharp ends or moving parts. The cannula does not transect but radially stretches and elevates vessels, fascia, and muscle fibers, preserving the fascia's natural gridiron shutter mechanism at the access site. The outer thread stabilizes the cannula, and no fascial suture is necessary. In a prospective clinical trial between 1994 and 1997, the instrument was used in 203 patients requiring 234 access ports for diagnostic and operative laparoscopies. No device-related complications or failed attempts were recorded. The cannula caused less tissue trauma at access sites, and may decrease the frequency of hernias and postoperative access site pain.  相似文献   

19.
Objective:We aimed to analysis the HER2 gene status and its relationship with p21 protein expression in gastric carcinoma.Methods:Fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) techniques were used to detect HER2 gene status and p53 protein in 59 cases of gastric cancer.Results:FISH detection of HER2 gene amplification rate was 16.9% (10/59),HER2 gene amplification in 49 cases without copy number gain and gene amplification were a total of 49.2% (29/59).HER2 protein expression was 42.4% (25/59),HER2 gene amplification rates in patients with +++,++ HER2 protein expression were 3/3 and 5/8,while in patients with + HER2 protein expression,it was 2/14,there was significant difference (P < 0.05).p21 protein expression rate was 49.2% (29/59),HER2 gene amplification rates and p21 protein expression had significant difference in tumor invasion depth,lymph node metastasis (P < 0.05);had no statistical significance in histological type,age,gender differences (P > 0.05).Conclusion:HER2 gene amplification rate and gene copy number had positively correlation with p21 protein expression,HER2 gene status and expression of p21 protein combined detection can provide a reference value in gastric cancer metastasis,patient's condition development and prognosis,it also can guide clinical development of individual treatment.  相似文献   

20.
A case of acute cholecystitis in an immunosuppressed patient with hepatocellular dysfunction is reported. The diagnostic dilemmas posed by the lack of specific sonographic findings, the possibility of acute gallbladder disease without early cystic duct obstruction, and the absence of clear guidelines for the interpretation of delayed appearance of the gallbladder on hepatobiliary scintigraphy in this subgroup of patients are discussed.  相似文献   

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