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1.
Although neither Klinefelter syndrome nor monozygotic twins are particularly rare (1/667 male births and 3–4/1000 live births, respectively), the occurrence of both in the same pregnancy (ie, identical twins with Klinefelter syndrome) is exceedingly rare and has only been reported three times previously in the literature. This report describes the fourth ever reported case of monozygotic twins with Klinefelter syndrome (who presented to our male fertility clinic with failure to conceive) and sheds interesting light on the reproductive concordance observed with this rare clinical entity. To our knowledge, this is the first reported case of monozygotic twins with Klinefelter syndrome that describes the infertility workup and outcomes of microsurgical testicular sperm extraction.Key words: Klinefelter syndrome, Microsurgical testicular sperm extraction, Azoospermia, Sertoli only syndrome, Germ cell aplasiaKlinefelter syndrome, the most common sex chromosome disorder in men, is the clinical result of an additional X chromosome in human males. This syndrome, which affects an estimated 1 in 667 live male births, most commonly manifests as 47,XXY, but may also take the form of 46,XY/47,XXY (Klinefelter mosaicism), 48,XXXY, or 49,XXXXY.1 Typical clinical manifestations of the syndrome include primary infertility, atrophic testes, hypergonadotropic hypogonadism, gynecomastia, eunuchoidism, and decreased facial and body hair.1 This condition often goes undiagnosed in prepubertal boys, and even in adult men, despite the physical hallmarks of the syndrome; many cases come to light only during the evaluation of primary male factor infertility. The andrologist, therefore, plays a central role in the diagnosis, work-up, and management of men with Klinefelter syndrome.With an incidence approximately twice that of Klinefelter (3–4 per 1000 live births worldwide),2 monozygotic (identical) twinning occurs when one fertilized egg splits and divides into two embryos. Monozygotic twins have been observed with various karyotypic abnormalities, including trisomy 21,3 trisomy 18,4 and trisomy 13.5 However, the presentation of monozygotic twins with Klinefelter syndrome (a fertilized egg with a 47, XXY karyotype splitting to produce identical embryos with Klinefelter syndrome) is exceedingly rare. In this report, we discuss one case of identical twin brothers diagnosed with Klinefelter syndrome at our fertility clinic (Glickman Urological & Kidney Institute, Cleveland, OH) as part of a work-up for inability to conceive.  相似文献   

2.
Structures of mitochondrial bc 1 complex have been reported based on four different crystalforms by three different groups. In these structures, the extrinsic domain of the Rieske [2Fe–2S]protein, surprisingly, appeared at three different positions: the c 1 position, where the [2Fe–2S]cluster exists in close proximity to the heme c 1; the b position, where the [2Fe–2S] clusterexist in close proximity to the cytochrome b; and the intermediate position where the[2Fe–2S] cluster exists in between c 1 and b positions. The conformational changes betweenthese three positions can be explained by a combination of two rotations; (1) a rotation of theentire extrinsic domain and (2) a relative rotation between the cluster-binding fold and thebase fold within the extrinsic domain. The hydroquinone oxidation and the electron bifurcationmechanism at the QP binding pocket of the bc 1 complex is well explained using theseconformational changes of the Rieske [2Fe–2S] protein.  相似文献   

3.
Klinfelter syndrome was first described in adult males with gynecomastia, azoospermia and hypergonadotropic hypogonadism. Children with the 47, XXY karyotype demonstrate few clinical findings so Klinefelter syndrome is rarely diagnosed until adult life. Besides children who have been diagnosed during prenatal genetic testing, in infancy a male with 47, XXY (or variants: 46, XY-47, XXY; 48, XXXY; 48, XXYY, 49, XXXXY) may be found while undergoing evaluation of micropenis, hypospadias, cryptorchidism or facial anomalies. The older child may present with learning disabilities, behavior disorders or tall stature. At the time of puberty, the clinical picture includes small testes, gynecomastia and an eunuchoid habitus. Early diagnosis of Klinefelter syndrome must be performed since it has been demonstrated that early treatment with androgens may ameliorate many aspects of the clinical symptoms and attenuate or prevent behavioral and psychiatric disorders associated with 47, XXY males.  相似文献   

4.
Cleft lip (CL) and/or palate (CP) are uncommon anomalies in Turner syndrome (TS) series. We report two unrelated sporadic 46,X,i(Xq) patients exhibiting orofacial clefts and a peculiar facial appearance masking the clinical diagnosis. CL, and CP in case 1 and CP in case 2, though non-specific of TS, may not be fortuitous findings. The increased frequency of CP and bifid uvula in poly X syndromes, the dermatoglyphic similarities between iXq TS and X polysomies, and the occurrence of Klinefelter phenotype when extra Xq material is present in a male, are all indirect evidences suggesting that Xq material cannot be considered phenotipically inert and facial clefts found in our patients may be syndromal manifestation of trisomic Xq dosage.  相似文献   

5.
Disulfide bonds in soybean trypsin inhibitor (Kunitz) were simultaneously reduced and alkylated using tri-n-butylphosphine and 2-vinylquinoline at pH 7.6 in 0.11 M Tris-4.4 M urea, 41% ethanol. The resulting S--2-quinolylethylated protein (2-QE-STI) has a new absorption peak at 315–318 nm. Its quinoline fluorescence can be excited above 310 nm independently of intrinsic protein fluorescence. Free 2-quinolylethylcysteine (2-QEC) shows unexpectedly weak fluorescence. Quinoline absorption in 2-QEC and 2-QE-STI changes with pH. The apparentpK values determined spectrophotometrically are near 5 for 2-QEC and 3 for 2-QE-STI. Fluorescence decreased with increasing pH and in the presence of chloride ions. Both structural and charge effects thus appear to influence the absorption and fluorescence of the quinoline group. Corrected fluorescence emission (excited at 316 nm) of neutral 2-QE-STI diluted in 0.1 N H2SO4 was directly proportional to concentration in the range 0.4–8 m 2-QEC. The 2-QEC content of the protein derivative determined by UV absorption at pH 1.5 was in agreement with the expected value of four residues per mole. Fluorescence measurements ofS-2-quinolylethylated proteins may be especially useful as a sensitive, specific assay for cyst(e)ine residues.Reference to a company or product name does not imply approval or recommendation of the product by the U.S. Department of Agriculture to the exclusion of others that may be suitable.Abbreviations used are Mops: 3-(N-morpholino)propanesulfonic acid; STI: soybean trypsin inhibitor (Kunitz); 2-PE-STI:S--2-pyridylethylated STI; 2-QEC:S--(2-quinolylethyl)-l-cysteine; 2-QE-STI:S--2-quinolylethylated STI; TosPheCH2-trypsin: bovine trypsin treated withp-toluenesulfonyl phenylalanine chloromethyl ketone.  相似文献   

6.
49,XXXXY syndrome is a rare sex chromosome aneuploidy and characterized by mental retardation, skeletal defects, craniofacial anomalies and hypogonadism. The increased frequency of diabetes mellitus in patients with Klinefelter syndrome and other types of X-chromosome polysomy has been reported, but no cases of diabetes mellitus in adult with 49,XXXXY syndrome have been reported so far. We report an 18-year-old patient with 49,XXXXY syndrome accompanying diabetes mellitus.  相似文献   

7.
Summary The X-chromosome of the chinchilla is the largest member of the complement. Since its area equals approximately 9% of that of the haploid autosome set, it may represent a duplicate-type X-chromosome, in contrast to the original-type in which the ratio X:autosomes ranges from 5 to 6.5%. Unlike other known species with the duplicate-type X-chromosome, the chinchilla possesses a very small Y-chromosome.It was inferred from the allocyclic behavior and asynchronous replication pattern of the sex chromosomes in somatic cells that one X-chromosome in the female and the male X-chromosome manifest a single genetically active region: the presumed active segment is inserted in the longer arm adjacent to the centromere. The remainder of these X-chromosomes, the entire second X-chromosome in the female and the Y-chromosome displayed positive heteropycnosis in mitotic prophase and completed DNA synthesis prior to mitosis later than any other elements: this cytologic behavior was held to reflect genetic inertness.The existence of genetic inactivation of much of the duplicate-type X-chromosome mass of the chinchilla supports the hypothesis that a constant optimal ratio between the functional portion of the X-chromosomes and the autosomes is maintained in mammals despite a wide range of relative sizes of the X-chromosomes.In female meiosis there is a free exchange of chiasmata between the X-chromosomes at first meiotic metaphase. In the male, however, the association between the large X- and small Y-chromosomes during meiosis is invariably end-to-end, denoting the absence of synapsis. This contrasts with the occurrence of side-by-side pairing of the XY-bivalent in other mammals possessing the duplicate-type X-chromosome but in which the Y-chromosome is correspondingly large.Supported by USPHS research grants HD 00544, GM 10210 and CA 05138.John and Mary R. Markle Scholar in Academic Medicine.The authors gratefully acknowledge the valuable technical assistance of Miss Sarah F. Holt and Mr. Richard J. Low.  相似文献   

8.
Chromosomal aberrations were comparatively assessed in nuclei extracted from synovial tissue, primary-culture (P-0) synovial cells, and early-passage synovial fibroblasts (SFB; 98% enrichment; P-1, P-4 [passage 1, passage 4]) from patients with rheumatoid arthritis (RA; n = 21), osteoarthritis (OA; n = 24), and other rheumatic diseases. Peripheral blood lymphocytes (PBL) and skin fibroblasts (FB) (P-1, P-4) from the same patients, as well as SFB from normal joints and patients with joint trauma (JT) (n = 4), were used as controls. Analyses proceeded by standard GTG-banding and interphase centromere fluorescence in situ hybridization. Structural chromosomal aberrations were observed in SFB (P-1 or P-4) from 4 of 21 RA patients (19%), with involvement of chromosome 1 [e.g. del(1)(q12)] in 3 of 4 cases. In 10 of the 21 RA cases (48%), polysomy 7 was observed in P-1 SFB. In addition, aneusomies of chromosomes 4, 6, 8, 9, 12, 18, and Y were present. The percentage of polysomies was increased in P-4. Similar chromosomal aberrations were detected in SFB of OA and spondylarthropathy patients. No aberrations were detected in i) PBL or skin FB from the same patients (except for one OA patient with a karyotype 45,X[10]/46,XX[17] in PBL and variable polysomies in long-term culture skin FB); or ii) synovial tissue and/or P-1 SFB of normal joints or of patients with joint trauma. In conclusion, qualitatively comparable chromosomal aberrations were observed in synovial tissue and early-passage SFB of patients with RA, OA, and other inflammatory joint diseases. Thus, although of possible functional relevance for the pathologic role of SFB in RA, these alterations probably reflect a common response to chronic inflammatory stress in rheumatic diseases.  相似文献   

9.
The assignment of the trivial name to new isolated or detected brassinosteroid is based on the trivial names of seven different brassinosteroids, with names assigned according to the plant source from which they were first isolated. To avoid some observed mistakes in assigning trivial names to these compounds and the impractical constant usage of their systematic names, we propose a semisystematic nomenclature of brassinosteroids, in which (22R,23R)-2,3,22,23-tetrahydroxy-5-campestane, the trivial name of which is 6-deoxocastasterone, is considered the functional parent compound and is named brassinostane or brassinane. A set of rules for naming the remaining natural brassinosteroids is presented.  相似文献   

10.
Heterochromatin protein 1 (HP1) is one of the nonhistone chromosomal components tightly associated with the pericentromeric heterochromatic region in Drosophila. The human homologue of HP1 is recognized by a subpopulation of anti-centromere antibodies (ACA). Such autoantibodies recognize a group of several nuclear proteins with Mr of 23–25 kDa and have been termed anti-chromo antibodies (AChA) because an evolutionarily conserved N-terminal half called the chromo domain of HP1 is the epitope. In this study, 84 ACA sera were examined by immunoblotting with recombinant 25-kDa chromo protein (p25). The p25 antigen was expressed as a glutathione S-transferase-fusion protein in E. coli and purified with glutathione-sepharose. Except for one serum specimen, AChA-positive sera reacted with the N-terminus (a.a 16–106) and/or the C-terminus (a.a. 83–191) of p25. Autoimmune response against the N-terminus of p25 in 33 patients was significantly associated with systemic lupus erythematosus and significantly related to leukopenia, thrombocytopenia and elevated erythrocyte sedimentation rate; C-terminal reactivity in 30 patients was significantly associated with primary Sjogren's syndrome and related to leukopenia. The internal 64-amino acid stretch (a.a. 43–106) with DNA-binding activity was not autoantigenic. p25 has two separate homologous regions to Drosophila HP1 at the N- and C-termini; the chromo domain and the chromo shadow domain. Patients with autoimmune responses against these conserved domains might form a clinical subset of patients positive for ACA.Abbreviations ACA anti-centromere antibodies - AChA anti-chromo antibodies - CENP centromere protein - DM dermatomyositis - ESR erythrocyte sedimentation rate - GST glutathione S-transferase - HP1 heterochromatin protein 1 - p25 25-kDa chromo protein - SLE systemic lupus erythematosus - SS Sjogren's syndrome - SSc systemic sclerosis - WBC white blood cell  相似文献   

11.
An -N-acetylgalactosaminidase IV able to remove blood type specificity of human A(II)-erythrocytes and not effecting B(III)-erythrocytes was isolated from the marine bacterium Arenibacter latericius KMM 426T. The -N-acetylgalactosaminidase IV preparation exhibits high activity during inhibition of hemagglutination with blood group substance A containing determinants analogous to A-erythrocytes. The enzyme has a pH optimum from 7.0 to 8.0 and completely retains its activity during 30-min heating at 50°C and for a week at 20°C. The enzyme can be stored under the sterile conditions for any length of time at 4°C, but it does not withstand freezing. The -N-acetylgalactosaminidase is resistant to NaCl; for p-nitrophenyl--N-acetyl-D-galactosaminide, the K m is 0.38 mM. The molecular mass of the enzyme determined by gel filtration is 84 kD.  相似文献   

12.
Summary 97 lethal and semilethal mutations were induced by ethyl methanesulfonate, nitrosomethyl urea and -irradiation in the 2D3-F5 region of the X-chromosome of D. melanogaster. Approximately 1 per cent of the tested X-chromosomes carried a lethal in the 2D3-2F5 region. The mutation frequencies per band or DNA content in this region and the whole X-chromosome are equal.Complementation analysis revealed at least 10 functionally independent essential loci in this region including about 10 bands. The data presented in this study support the one bandone gene hypothesis.The Pgd locus coding for 6-phosphogluconate dehydrogenase (6PGD) is mapped in the 2D3 (or 2D4) band. Isolation of 11 lethal or semilethal point mutations with null or reduced 6PGD activity shows that the Pgd locus is a vital one.  相似文献   

13.
Summary A natural product, Sch 42029, isolated from the fermentation of anActinoplanes sp. (SCC 1971) was found to displace Sch 23390 from the dopamine-1 (D1) receptor. The compound was isolated from the fermentation broth by adsorption of the filtrate on XAD-16 resin, elution with water-methanol, followed by purification by gel-permeation chromatography and HPLC. Using spectroscopic analysis, the structure was determined to be 2,5-dihydroxy acetanilide. The pure compound displaced Sch 23390, a D1-selective ligand, at aK i of 1.6 m and spiperone, a D2-selective ligand, at aK i of 200 m.  相似文献   

14.
The modulatory effects of noradrenergic agonists on the 25 mM K+-induced release of [3H]dopamine (3H-DA) from rat brain nucleus accumbens slices was investigated, using a superfusion technique. The K+-induced release of3H-DA was Ca2+ dependent, significantly enhanced (25–32%;p<0.02) by the -adrenoceptor agonist isoproterenol (10 M), and significantly decreased (13–25%;p<0.05) by the 2-adrenoceptor agonist clonidine (10 M). At these concentrations neither drug affected basal release of3H-DA. Clonidine (100 M) increased the basal release of3H-DA, while decreasing the K+-induced release by 19% (p<0.01). The inclusion of desipramine in the incubation medium, to prevent accumulation of3H-DA into noradrenergic neurons, did not alter the inhibitory effect of clonidine (10 M) on3H-DA release. This study provides direct evidence that noradrenergic neurons can modulate dopaminergic neurotransmission in the mesolimbic system.  相似文献   

15.
Gender Dysphoria is characterized by a marked incongruence between the cerebral sex and biological sex. To investigate the possible influence of karyotype on the etiology of Gender Dysphoria we carried out the cytogenetic analysis of karyotypes in 444 male-to-females (MtFs) and 273 female-to-males (FtMs) that attended the Gender Identity Units of Barcelona and Málaga (Spain) between 2000 and 2016. The karyotypes from 23 subjects (18 MtFs and 5 FtMs) were also analysed by Affymetrix CytoScan? high-density (HD) arrays. Our data showed a higher incidence of cytogenetic alterations in Gender Dysphoria (2.65%) than in the general population (0.53%) (p?<?0.0001). When G-banding was performed, 11 MtFs (2.48%) and 8 FtMs (2.93%) showed a cytogenetic alteration. Specifically, Klinefelter syndrome frequency was significantly higher (1.13%) (p?<?0.0001), however Turner syndrome was not represented in our sample (p?<?0.61). At molecular level, HD microarray analysis revealed a 17q21.31 microduplication which encompasses the gene KANSL1 (MIM612452) in 5 out of 18 MtFs and 2 out of 5 FtMs that corresponds to a copy-number variation region in chromosome 17q21.31. In conclusion, we confirm a significantly high frequency of aneuploidy, specifically Klinefelter syndrome and we identified in 7 out of 23 GD individuals the same microduplication of 572 Kb which encompasses the KANSL1 gene.  相似文献   

16.
Summary An Indiana family segregating a syndrome of X-linked mental retardation and skeletal anomalies was tested for linkage of the mutant gene to X-chromosome molecular markers. Lod scores of 3.27 and 3.06 (-0) for the molecular probes St14-1 (DXS52) and Dx13 (DXS15), respectively, indicate that the disease gene is located in the terminal portion of Xq.  相似文献   

17.
Summary A study was made of the effect of genotype and temperature (25 and 17°C) on sex ratio in the hybrids D. virilis Sturt. X D. littoralis Sokolov. A genetic system has been found controlling sex-differential viability. In the F1 of the reciprocal hybrids D. virilis X D. littoralis the sex ratio is normal, though at 17°C females are slightly excessive. The abnormal sex ratio is observed only in the progeny of test crosses.The major gene causing the death of female progeny of the cross [ (, D. virilis x , D. littoralis) x D. virilis] x D. littoralis is located on chromosome 2 of D. virilis. It is expressed as a lethal if chromosome 5 is heterogeneous virilis-littoralis. Chromosome 3 of D. virilis bears a modifier-enhancer and chromosome 5, a suppressor, of this lethal found in chromosome 2. This genetic system has a maternal effect and functions at 25°C, interacting with the X-chromosome of D. littoralis. If the maintainance temperature is lowered to 17°C, the progeny of the cross hybrid FB1 x D. littoralis is predominantly female. Partial death of males is accounted for by a disturbance in the interaction between the genes of X-chromosome in certain combinations with the D. virilis autosomes and the Y-chromosome of the paternal species D. littoralis.Sex-differential mortality in the hybrids D. virilis x D. littoralis is one of the isolating factors between these species which does not appear to act until the second and subsequent F1 generations due to the formation of the recombination load.  相似文献   

18.
A cytogenetic procedure is described whereby a combination of polytene chromosome analysis and complementation mapping has permitted the unequivocal localization of ordinary sex-linked genes (those not covered by the Y-chromosome) in Section 20, the most proximal region of Bridges' (1938) map of the polytene X-chromosome. Thus far, eleven functional units in Section 20 distal to the bobbed locus, but none proximal, have been resolved. We suggest that the polytenized portion of Section 20, which heretofore has traditionally been considered as heterochromatic, corresponds, in fact, with the euchromatic portion of the mitotic X-chromosome.  相似文献   

19.
During the normal growth cycle of peanut (Arachis hypogaea L.) cells, cultured in suspension medium, cell aggregates of <0.5 mm were formed during the log phase and grew to aggregates of >0.5 mm during late growth phase. Calmodulin rose to its original level during <0.5 mm aggregate formation following an initial 50% drop. Observations by UV microscopy showed that calmodulin. Ca2+ was centered in intense fluorescent sites. Calmodulin antagonists and a calcium chelator inhibited <0.5 mm aggregate formation as well as protein accumulation. The chelator suppressed cationic peroxidase isozyme release, while the antagonists had some partial effect on the anionic isozyme. Some heavy metals such as cadmium, mercury, lead and cobalt at low concentrations would allow continued growth of >0.5 but not of the <0.5 populations. At high (1 mM) concentrations these ions caused arrested growth. At low (10 M) levels and in the presence of 3 mM calcium they had a synergistic effect.Abbreviations AOA amino oxy acetic acid - BCA big cell aggregates - CPZ chlorpromazine - EGTA ethylene glycol bis (-aminoethyl ether) - N, N, N, N tetra acetic acid - SCA small cell aggregates - TFP trifluoperazine  相似文献   

20.
49,XXXXY syndrome is a very rare condition that is associated with a considerable more severe phenotype than classic 47,XXY Klinefelter syndrome. We present a patient with 49,XXXXY syndrome, who was first presented to an endocrinological unit at the age of 12.5 years with prepubertal genitalia. He was then lost from follow-up and showed clear clinical and biochemical signs of hypergonadotropic hypogonadism when presenting again at the age of 16 years. The patient was started on testosterone replacement therapy. This case is reported to underline the need for thorough endocrinological follow-up examinations in males with X polysomies.  相似文献   

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