Discordant sex in monozygotic XXY/XX twins: a case report.

We report a case of discordant phenotypic sex in monozygotic twins mosaic 47,XXY/46,XX: monozygotic heterokaryotypic twins. The twins presented with cognitive and comprehension delay, behavioural and language disorders, all symptoms frequently reported in Klinefelter syndrome. Molecular zygosity analysis with several markers confirmed that the twins are in effect monozygotic (MZ). Array comparative genomic hybridization found no evidence for the implication of copy number variation in the phenotypes. Ultrasound scans of the reproductive organs revealed no abnormalities. Endocrine tests showed a low testosterone level in Twin 1 (male phenotype) and a low gonadotrophin level in Twin 2 (female phenotype) which, combined with the results from ultrasound examination, provided useful information for potentially predicting the future fertility potential of the twins. Blood karyotypes revealed the presence of a normal 46,XX cell line and an aneuploïd 47,XXY cell line in both patients. Examination of the chromosome constitutions of various tissues such as blood, buccal smear and urinary sediment not surprisingly showed different proportions for the 46,XX and 47,XXY cell lines, which most likely explains the discordant phenotypic sex and mild Klinefelter features. The most plausible underlying biological mechanism is a post-zygotic loss of the Y chromosome in an initially 47,XXY zygote. This would result in an embryo with both 46,XX and 47,XXY cells lines which could subsequently divide into two monozygotic embryos through a twinning process. The two cell lines would then be distributed differently between tissues which could result in phenotypic discordances in the twins. These observations emphasize the importance of regular paediatric evaluations to determine the optimal timing for fertility preservation measures and to detect new Klinefelter features which could appear throughout childhood in the two subjects.

Discordance between immunochemistry of mismatch repair proteins and molecular testing of microsatellite instability in colorectal cancer.

BACKGROUND: DNA mismatch repair system deficiency (dMMR) is found in 15% of colorectal cancers (CRCs). Two methods are used to determine dMMR, immunohistochemistry (IHC) of MMR proteins and molecular testing of microsatellite instability (MSI). Only studies with a low number of patients have reported rates of discordance between these two methods, ranging from 1% to 10%. MATERIALS AND METHODS: Overall, 3228 consecutive patients with CRCs from two centers were included. Molecular testing was carried out using the Pentaplex panel and IHC evaluated four (MLH1, MSH2, MSH6, and PMS2; cohort 1; n = 1085) or two MMR proteins (MLH1 and MSH2; cohort 2; n = 2143). The primary endpoint was the rate of discordance between MSI and MMR IHC tests. RESULTS: Fifty-one discordant cases (1.6%) were initially observed. Twenty-nine out of 51 discordant cases were related to IHC misclassifications. In cohort 1, after re-reading IHC and/or carrying out new IHC, 16 discordant cases were reclassified as nondiscordant. In cohort 2, after the addition of MSH6/PMS2 IHC and re-examination, 13 were reclassified as nondiscordant. In addition, 10 misclassifications of molecular tests were identified. Finally, only 12 discordant cases (0.4%) remained: 5 were proficient MMR/MSI and 7 were dMMR/microsatellite stable. CONCLUSIONS: Our study confirmed the high degree of concordance between MSI and MMR IHC tests. Discordant cases must be reviewed, and if needed, tests must be repeated and analyzed by an expert team.

The antithrombotic potential of dalteparin in man assessed indirectly by Wessler's technique.

The aim of this study was to demonstrate the effectiveness of a new experimental approach for assessing the antithrombotic potential of low molecular weight heparins (LMWH) such as dalteparin. In this approach, sera obtained from healthy volunteers treated with various i.v. doses of dalteparin (30, 60 or 120 anti-Xa IU/kg) or placebo (physiological saline) were used as the thrombogenic challenge in a Wessler's stasis model of experimental venous thrombosis in the rat. Sera from placebo-treated volunteers showed a stable thrombogenic activity (0.25 ml/kg of serum producing thrombi of about 50 mg wet weight). Sera from healthy volunteers having previously received dalteparin however demonstrated dose- and time-related reductions in their thrombogenic activity. Half-lives of these effects were 300. 444 and > 480 min for 30, 60 and 120 anti-Xa IU/kg dalteparin respectively. These values were significantly higher than the corresponding anti-Xa and anti-IIa half-lives.

[Desmoid fibroma of the scapula. Recurrence with pulmonary metastasis]. / Fibrome desmoïde de l'omoplate--récidive avec métastases pulmonaires.

A 22 year old woman presented with a desmoid tumour located in the subspinal fossa of the right scapula. A recurrence was observed 3 years after local excision. This recurrence was accompanied by pulmonary metastases. A new excision of the tumour and a pulmonary biopsy confirmed the similarity of that tumour with the original one. Six years after the initial operation the pulmonary lesions extended in spite of chemotherapy. The pulmonary metastases of the desmoid fibromata are exceptional and only three cases have been described in literature, with fatal outcome.

Efficacy and safety of low, standard, and high dosages of an estradiol transdermal system (Esclim) compared with placebo on vasomotor symptoms in highly symptomatic menopausal patients. The Esclim Study Group.

OBJECTIVE: Our purpose was to evaluate the efficacy and safety of 3 dosages of Esclim, delivering 0.025 mg, 0.050 mg, or 0.100 mg 17beta-estradiol per 24 hours, in the treatment of moderate to severe vasomotor symptoms. STUDY DESIGN: In this double-blind, placebo-controlled, parallel-group, multicenter trial, 196 highly symptomatic menopausal women received 12 weeks of continuous unopposed treatment with 1 of the 3 dosages of Esclim or a matching placebo patch. RESULTS: The reduction in frequency of moderate to severe vasomotor symptoms was statistically significant compared with placebo (P <.05) from week 2 onward in the Esclim 50 and 100 groups and from week 3 onward in the Esclim 25 group. Symptom severity was also reduced. Estrogen-related adverse events, particularly metrorrhagia and endometrial hyperplasia, were less frequent in the Esclim 25 group than in the higher-dosage groups. CONCLUSION: All 3 dosages of Esclim were effective in the treatment of vasomotor symptoms. The efficacy and safety of Esclim 25 indicate a good risk-benefit ratio.