Recurrent and founder mutations in the Netherlands: cardiac Troponin I (TNNI3) gene mutations as a cause of severe forms of hypertrophic and restrictive cardiomyopathy

Background About 2-7% of familial cardiomyopathy cases are caused by a mutation in the gene encoding cardiac troponin 1 (TNNI3). The related clinical phenotype is usually severe with early onset. Here we report on all currently known mutations in the Dutch population and compared these with those described in literature. Methods TheTNNI3 gene was screened for mutations in all coding exons and flanking intronic sequences in a large cohort of cardiomyopathy patients. All Dutch index cases carrying a TNNI3 mutation that are described in this study underwent extensive cardiological evaluation and were listed by their postal codes. Results In 30 families, 14 different mutations were identified. Three TNNI3 mutations were found relatively frequently in both familial and non-familial cases of hypertrophic cardiomyopathy (HCM) or restrictive cardiomyopathy (RCM). Haplotype analysis showed that p. Arg145Trp and p.Ser166Phe are founder mutations in the Netherlands, while p.Glu209Ala is not. The majority of Dutch TNNI3 mutations were associated with a HCM phenotype. Mean age at diagnosis was 36.5 years. Mutations causing RCM occurred less frequently, but were identified in very young children with a poor prognosis. Conclusion In line with previously published data, we found TNNI3 mutations to be rare and associated with early onset and severe clinical presentation

Maternal morbidity in the first year after childbirth in Mombasa Kenya; a needs assessment

<p>Abstract</p> <p>Background</p> <p>In sub-Saharan Africa, few services specifically address the needs of women in the first year after childbirth. By assessing the health status of women in this period, key interventions to improve maternal health could be identified. There is an underutilised opportunity to include these interventions within the package of services provided for woman-child pairs attending child-health clinics.</p> <p>Methods</p> <p>This needs assessment entailed a cross-sectional survey with 500 women attending a child-health clinic at the provincial hospital in Mombasa, Kenya. A structured questionnaire, clinical examination, and collection of blood, urine, cervical swabs and Pap smear were done. Women's health care needs were compared between the early (four weeks to two months after childbirth), middle (two to six months) and late periods (six to twelve months) since childbirth.</p> <p>Results</p> <p>More than one third of women had an unmet need for contraception (39%, 187/475). Compared with other time intervals, women in the late period had more general health symptoms such as abdominal pain, fever and depression, but fewer urinary or breast problems. Over 50% of women in each period had anaemia (Hb <11 g/l; 265/489), with even higher levels of anaemia in those who had a caesarean section or had not received iron supplementation during pregnancy. Bacterial vaginosis was present in 32% (141/447) of women, while 1% (5/495) had syphilis, 8% (35/454) <it>Trichomonas vaginalis </it>and 11% (54/496) HIV infection.</p> <p>Conclusion</p> <p>Throughout the first year after childbirth, women had high levels of morbidity. Interface with health workers at child health clinics should be used for treatment of anaemia, screening and treatment of reproductive tract infections, and provision of family planning counselling and contraception. Providing these services during visits to child health clinics, which have high coverage both early and late in the year after childbirth, could make an important contribution towards improving women's health.</p

Disease-Related Cardiac Troponins Alter Thin Filament Ca2+ Association and Dissociation Rates

The contractile response of the heart can be altered by disease-related protein modifications to numerous contractile proteins. By utilizing an IAANS labeled fluorescent troponin C, , we examined the effects of ten disease-related troponin modifications on the Ca2+ binding properties of the troponin complex and the reconstituted thin filament. The selected modifications are associated with a broad range of cardiac diseases: three subtypes of familial cardiomyopathies (dilated, hypertrophic and restrictive) and ischemia-reperfusion injury. Consistent with previous studies, the majority of the protein modifications had no effect on the Ca2+ binding properties of the isolated troponin complex. However, when incorporated into the thin filament, dilated cardiomyopathy mutations desensitized (up to 3.3-fold), while hypertrophic and restrictive cardiomyopathy mutations, and ischemia-induced truncation of troponin I, sensitized the thin filament to Ca2+ (up to 6.3-fold). Kinetically, the dilated cardiomyopathy mutations increased the rate of Ca2+ dissociation from the thin filament (up to 2.5-fold), while the hypertrophic and restrictive cardiomyopathy mutations, and the ischemia-induced truncation of troponin I decreased the rate (up to 2-fold). The protein modifications also increased (up to 5.4-fold) or decreased (up to 2.5-fold) the apparent rate of Ca2+ association to the thin filament. Thus, the disease-related protein modifications alter Ca2+ binding by influencing both the association and dissociation rates of thin filament Ca2+ exchange. These alterations in Ca2+ exchange kinetics influenced the response of the thin filament to artificial Ca2+ transients generated in a stopped-flow apparatus. Troponin C may act as a hub, sensing physiological and pathological stimuli to modulate the Ca2+-binding properties of the thin filament and influence the contractile performance of the heart