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Twins Discordant (twin + discordant)
Kinds of Twins Discordant Selected AbstractsThe influence of the polymorphism in apolipoprotein B codon 2488 on insulin and lipid levels in a Danish twin populationDIABETIC MEDICINE, Issue 1 2002J. Bentzen Abstract Aims The apolipoprotein B codon 2488 polymorphism has been associated with the metabolism of lipoproteins in subjects with Type 2 diabetes. However, no data are available on the influence of the polymorphism on insulin or glucose metabolism. This study examines the impact of the polymorphism on parameters associated with the insulin resistance syndrome in Danish twins. Methods The effect of the polymorphism on lipid, glucose and insulin measures was studied in 548 same sex twins aged 55,74 years. Results The codon 2488 polymorphism influenced fasting triglyceride levels, as well as insulin, as measured at 120 min in an oral glucose tolerance test. Subjects with the genotype T2488T had 14% higher triglyceride levels (P = 0.02) and 31% higher insulin levels (P = 0.004) than subjects with genotype C2488C. In twins discordant for genotype, the T-allele was associated with higher levels of triglyceride (P = 0.04) and insulin (P = 0.02) and lower levels of HDL-cholesterol (P = 0.04). Conclusion The T-allele of the codon 2488 polymorphism influenced parameters related to the insulin resistance syndrome, i.e. increased levels of insulin, increased levels of triglyceride and decreased levels of HDL. As the polymorphism is silent, these effects must be mediated through linkage to other polymorphisms in apolipoprotein B or other genes on chromosome 2. [source] Elevated cerebrospinal fluid adiponectin and adipsin levels in patients with multiple sclerosis: a Finnish co-twin studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2010A. Hietaharju Background and purpose:, The aim of this study was to investigate the levels of three adipocytokines: leptin, adiponectin and adipsin, in serum and cerebrospinal fluid (CSF) of twins discordant for multiple sclerosis (MS). Adipose tissue is an important component connecting immune system and several tissues and organs including CNS. Fat cells produce adipocytokines, which seem to have a role in various autoimmune disorders including MS. Methods:, Plasma samples were collected from twelve twins and CSF samples from four twins discordant for MS. The concentrations of interleukine (IL)-6, adiponectin, adipsin and leptin in plasma and CSF samples were determined by enzyme immuno assay. Results:, A significant difference was seen in the adipocytokine levels in CSF samples. Twins with MS had higher concentrations of adiponectin (P = 0.039) and adipsin (P = 0.039), than their asymptomatic co-twins. Conclusion:, As adiponectin and adipsin levels in CSF did not correlate with their levels in plasma, it seems that there could be a secondary intrathecal synthesis of these adipocytokines in MS. [source] Specific bronchoalveolar lavage fluid T cells associate with disease in a pair of monozygotic twins discordant for sarcoidosisJOURNAL OF INTERNAL MEDICINE, Issue 6 2001J. Grunewald Abstract.,Grunewald J, Eklund A (Karolinska Hospital, Stockholm, Sweden). Specific bronchoalveolar lavage fluid T cells associate with disease in a pair of monozygotic twins discordant for sarcoidosis (Case report). J Intern Med 2001; 250: 535,539. A 49-year-old Caucasian woman had an acute onset of sarcoidosis. Bronchoscopy with bronchoalveolar lavage (BAL) showed a pronounced accumulation of BAL fluid CD4+ T cells expressing the T-cell receptor (TCR) AV2S3 gene. In line with this observation, the patient was HLA-DR17 positive, previously shown to strongly correlate with lung compartmentalized AV2S3+ T cells. At follow-up after recovery, reduced numbers of BAL fluid AV2S3+ T cells were found. Interestingly, BAL fluid of a healthy monozygotic twin sister contained normal numbers of AV2S3+ lung T cells. This report shows the T-cell repertoire of BAL fluid T cells to correlate with the disease (sarcoidosis), indicating a local and specific immune response triggered by an unknown antigen in sarcoidosis. [source] Disc degeneration and bone density in monozygotic twins discordant for insulin-dependent diabetes mellitusJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2000T. Videman The effects of insulin-dependent diabetes mellitus on bone density and connective tissue degeneration have theoretical interest and practical relevance. Several experimental studies in animals have demonstrated the harmful effects of insulin deficiency on connective tissues. However, clinical studies in humans have produced somewhat contradictory results, most likely due to difficulties controlling for general degeneration and factors associated with diabetes. In nine pairs of monozygotic twins discordant for insulin-dependent diabetes mellitus, we compared femoral and lumbar bone mineral density (assessed by dualenergy x-ray absorptiometry) and spinal degeneration (assessed by magnetic resonance imaging). The bone densities were, on average, 0.1,0.3% lower (p = 0.87,0.96) in diabetic patients. However, after controlling for smoking, we found that the bone density in the femoral neck was 2.5% (0.025 g/cm2) lower in diabetic individuals than in their twins (p = 0.09). The five magnetic resonance imaging parameters used to evaluate discdegeneration did not differ between diabetic patients and their twins. In conclusion, our results provide no evidence that insulin-dependent diabetes mellitus has any major effect on bone density or disc degeneration. [source] Monochorionic-diamniotic twins discordant in gender from a naturally conceived pregnancy through postzygotic sex chromosome loss in a 47,XXY zygotePRENATAL DIAGNOSIS, Issue 8 2008Nicolas H. Zech Abstract Objective It is generally believed that monochorionic-diamniotic twin pregnancies result from one fertilized oocyte with both siblings having the same genotype and phenotype. In rare instances, due to somatic mutations or chromosome aberrations, the karyotypes and phenotypes of the two twins can differ. Method We report cytogenetic, molecular genetic and clinical examinations in monochorionic-diamniotic twins discordant in gender. Results The monochorionic-diamniotic status of the twins was diagnosed by ultrasound and histologic examination of the placenta. Prenatal chromosome examination performed on amniocytes revealed a normal female karyotype in one and a 46,XX(26)/46,XY(3) karyotype in the other twin. Molecular examinations confirmed monozygosity despite discordant sex. Based on the cytogenetic and molecular results of lymphocytes and placental cells, the only explanation for gender discordance was that the conceptus originally had a 47,XXY chromosome complement. Conclusion A 47,XXY zygote appears to have undergone a twinning process. A postzygotic loss of the X chromosome in some cells and the Y chromosome in other cells, either before or after twinning, resulted in 46,XX/46,XY mosaicism in both monozygotic (MZ) twins. The sex discordance of the MZ twins can be explained by different proportions of the 46,XX and 46,XY cell lines in the gonads and other tissues. Copyright © 2008 John Wiley & Sons, Ltd. [source] Monochorionic and dichorionic twin pregnancies discordant for fetal anencephaly: a systematic review of prenatal management optionsPRENATAL DIAGNOSIS, Issue 4 2008Annelies Lust Abstract The aim of this study was to evaluate the effect of selective feticide (SF) compared to expectant management (EM) on perinatal outcome in dichorionic and monochorionic twins discordant for anencephaly. For this purpose, we conducted a systematic review of literature and added ten unpublished cases. As a result, we found that in dichorionic twins, mean gestational age (GA) at birth in the SF group was 38.0 weeks versus 34.9 weeks (P = 0.0002). Mean birth weight was 2922 g in the SF group versus 2474 g (P = 0.03). In monochorionic twins, mean GA at birth was 35.2 weeks versus 32.7 weeks (P = 0.1). Mean birth weight was 2711 g versus 1667 g (P = 0.0001). We conclude that while SF does not reduce perinatal mortality, it does result in significantly longer gestations and higher birth weight, and appears to be the management of choice in dichorionic twins discordant for anencephaly. In monochorionic twins, SF also increases birth weight, but in view of the complexity of this group, no clear recommendations can be made. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prenatal diagnosis of female monozygotic twins discordant for Turner syndrome: implications for prenatal genetic counsellingPRENATAL DIAGNOSIS, Issue 8 2002B. Gilbert Abstract We describe a set of monozygotic (MZ) female twins, one of whom presented with a typical Turner syndrome (TS) phenotype and the other a normal female phenotype. Prenatal fetal ultrasonographic examination showed a monochorial diamniotic pregnancy with a hygroma colli and growth delay in Twin A and no anomalies in Twin B. Karyotypic analysis performed on fetal blood samples demonstrated a 46,XX/45,X (23/2) mosaicism in Twin A and a normal 46,XX chromosome constitution in Twin B. At birth, Twin A presented with a typical TS and Twin B had a normal female phenotype. Postnatal cytogenetic investigation of blood lymphocytes showed the same 46,XX/45,X mosaicism in both twins: 46,XX/45,X (40/7) in Twin A and 46,XX/45,X (40/5) in Twin B. Further investigations at the age of 10,months showed in Twin A a 46,XX/45,X (98/2) mosaicism in lymphocytes and 100% of 45,X (50 analysed cells) in fibroblasts, and in Twin B a normal 46,XX (100 analysed cells) chromosome constitution in lymphocytes but a mild 46,XX/45,X (78/2) mosaicism in fibroblasts. Monozygosity was confirmed by molecular analysis. To our knowledge, this is the first report of prenatal diagnosis of MZ female twins discordant for TS. Review of reported sets of MZ female twins (eight cases) or triplets (one case) discordant for TS shows, as in the present case, that the phenotype correlates better with the chromosomal distribution of mosaicism in fibroblasts than in lymphocytes. In the blood of MZ twins chimerism may modify the initial allocation of the mosaicism. These results suggest that, in cases of prenatal diagnosis of MZ female twins discordant for TS, the phenotype of each twin would be better predicted from karyotype analysis of cells from amniotic fluid than from fetal blood. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||