Diet of Cnesterodon decemmaculatus (Poeciliidae) and Jenynsia multidentata (Anablepidae) in a hypertrophic shallow lake of Uruguay

Diet of Cnesterodon decemmaculatus (Jenyns, 1842) and Jenynsia multidentata (Jenyns, 1842) were analysed in Lake Rodó, an urban hypertrophic lake from Montevideo, Uruguay. Both species displayed omnivory. The most consumed items for C. decemmaculatus were zooplankton, periphyton, phytoplankton and detritus; the diet of J. multidentata included zooplankton, insects, crustaceans and juvenile fish. Our results suggest that both species could be acting as facultative planktivores. The fish community of this lake is characterised by the dominance of C. decemmaculatus and J. multidentata. Under this condition, predation on large-bodied zooplankton could indirectly be contributing to maintain a high phytoplankton abundance and a low water transparency.

Genome-wide linkage in a highly consanguineous pedigree reveals two novel loci on chromosome 7 for non-syndromic familial Premature Ovarian Failure.

BACKGROUND: The human condition known as Premature Ovarian Failure (POF) is characterized by loss of ovarian function before the age of 40. A majority of POF cases are sporadic, but 10-15% are familial, suggesting a genetic origin of the disease. Although several causal mutations have been identified, the etiology of POF is still unknown for about 90% of the patients.¦METHODOLOGY/PRINCIPAL FINDINGS: We report a genome-wide linkage and homozygosity analysis in one large consanguineous Middle-Eastern POF-affected family presenting an autosomal recessive pattern of inheritance. We identified two regions with a LOD(max) of 3.26 on chromosome 7p21.1-15.3 and 7q21.3-22.2, which are supported as candidate regions by homozygosity mapping. Sequencing of the coding exons and known regulatory sequences of three candidate genes (DLX5, DLX6 and DSS1) included within the largest region did not reveal any causal mutations.¦CONCLUSIONS/SIGNIFICANCE: We detect two novel POF-associated loci on human chromosome 7, opening the way to the identification of new genes involved in the control of ovarian development and function.

The SPONASTRIME dysplasia: familial short-limb dwarfism with saddle nose, spinal alterations and metaphyseal striation. Report of 4 siblings.

We report clinical, anthropometric and radiological findings in 4 siblings with a new type of skeletal dysplasia. 4 normally intelligent girls exhibit dwarfism between -3.4 and -4.6 standard deviations with accentuated shortening of the lower limbs, moderate deformity of the vertebral bodies, mildly striated metaphyses, saddle nose, frontal bossing, and relatively large head. The family pedigree suggests autosomal recessive inheritance. We propose the designation of SPONASTRIME dysplasia, derived from spondylar and nasal alterations with striation of the metaphyses.

A model for intra-familial distribution of an infectious disease (Chagas' disease)

A probabilistic model for intra-familial distribution of infectous disease is proposed and applied to the prevalence of positive serology for Trypanosoma cruzi infection in Northeastern Brazilian sample. This double with one tail excess model fits satisfactorily to the data and its interpretation says that around 51% of these 982 families are free of infection risk; among those that are at risk, 3% have a high risk (0.66), probably due to high domestic infestation of the vector bug; while 97% show a small risk (0.11), probably due to accidental, non-domestic transmission.

Electrocardiographic alteration among first degree relatives with serologic evidence of Trypanosoma cruzi infection: a sibship study

To analyze whether electrocardiographic alterations (ECGA) in patients with antibodies to Trypanosoma cruzi showed a patttern of familial aggregation, a sample of 379 young adults (166 men and 213 women) distributed in sibships, were assessed for the presence of anti-T.cruzi antibodies, and subjected to a complete clinical examination and a standard resting electrocardiogram (ECG). Positive T. cruzi serology was detected in 165 individuals, 48 of them showing an abnormal ECG (overall prevalence 29 por cento). One hundred and eleven seropositive individuals were distributed in 45 sibships, each of them constituted by more than one seropositive sib, with ECGA being present in 34 out of these patients. Seropositive subjects with ECGA were detected in 27 sibships. Since the index case within each sibship is counted exactly once, affected individuals selected at random as propositi were extracted to calculate the prevalence of ECGA among first degree relatives of probands. Abnormal ECGs were recorded in 7 out of 45 sibs yielding a prevalence that did not differ from estimations registered in the general population or seropositive sibs. Data from the present sample show no familial aggregation for the occurrence of ECGA in patients with T.cruzi infection.

Functional effects of Na+,K+-ATPase gene mutations linked to familial hemiplegic migraine.

Familial hemiplegic migraine type 2, an autosomal dominant form of migraine with aura, has been associated with four distinct mutations in the alpha2-subunit of the Na+,K+-ATPase. We have introduced these mutations in the alpha2-subunit of the human Na+,K+-ATPase and the corresponding mutations in the Bufo marinus alpha1-subunit and studied these mutants by expression in Xenopus oocyte. Metabolic labeling studies showed that the mutants were synthesized and associated with the beta-subunit, except for the alpha2HW887R mutant, which was poorly synthesized, and the alpha1BW890R, which was partially retained in the endoplasmic reticulum. [3H]ouabain binding showed the presence of the alpha2HR689Q and alpha2HM731T at the membrane, whereas the alpha2HL764P and alpha2HW887R could not be detected. Functional studies with the mutants of the B. marinus Na+,K+-ATPase showed a reduced or abolished electrogenic activity and a low K+ affinity for the alpha1BW890R mutant. Through different mechanisms, all these mutations result in a strong decrease of the functional expression of the Na+,K+-pump. The decreased activity in alpha2 isoform of the Na+,K+-pump expressed in astrocytes seems an essential component of hemiplegic migraine pathogenesis and may be responsible for the cortical spreading depression, which is one of the first events in migraine attacks.

Defective production of interleukin 2 in patients with Chagas' disease: purified IL-2 augments in vitro response in patients with chagasic cardiomyopathy

The production of interleukin 2 (IL-2) by peripheral blood mononuclear cells, from patients with different clinical forms of Chagas disease and healthy controls, was evaluated after stimulation with Trypanosoma cruzi antigen, PPD and PHA. PHA induced higher production of IL-2 in infected patients than healthy controls. No diferences were found between infected groups. With PPD the trend was similar, the only difference was that asymptomatic infected patients (INF) showed higher levels of IL-2 production than patients with cardiomyopathy (CDM). With T. cruzi antigen, most patients showed little or no IL-2 production at 24 hr, a peak at 48 hr and an abrupt fall at 72 hr. A similar pattern of IL- 2 production was observed in INF and CDM. To evaluate the physiologic relevance of the deficit in IL-2 production, we studied the effect of non-mitogenic concentratios of IL-2 in the proliferative response to specific antigens. The addition of IL-2 only enhanced the proliferative response of CDM patients. These observations suggest that patients suffering Chagas' disease, particularly CDM, have a significant reduction in the capacity to produce IL-2. These findings could be of importance in the pathogenesis of Chagas' disease.

Altering in vivo fate of heart-infiltrating progenitors from pro-fibrotic into F4/80+macrophages prevents progression of myocarditis into inflammatory dilated cardiomyopathy

Rationale: Experimental autoimmune myocarditis (EAM) mirrors important pathogenic aspects of inflammatory cardiomyopathy, a common cause of heart failure. In EAM, TGF-β-dependent conversion of heart-infiltrating prominin-1+ progenitors into myofibroblasts is critical for development of fibrosis and the end-stage heart failure phenotype. Therapeutic strategies modulating the in vivo fate of prominin-1+ progenitors might therefore prevent TGF-β-mediated cardiac fibrosis and pathological remodelling. Methods and Results: EAM was induced in BALB/c mice using alpha-myosin heavy chain (aMyHC) peptide/complete Freund's adjuvant (CFA) immunization. Prominin-1+ cells were isolated from the inflamed hearts at day 21 after immunization, expanded and treated with Macrophage Colony-Stimulating Factor (M-CSF) or Transforming Growth Factor-beta (TGF-β). Herein, we demonstrated that M-CSF turns, ex vivo and in the EAM, heart-infiltrating prominin-1+ progenitors into immunosuppressive F4/80/CD11b/CD16/32/NOS2-expressing, nitric oxide producing and E.coli bacteria phygocyting macrophages, and protect further TGF-β-stimulated differentiation into pathogenic myofibroblasts. Systemic M-CSF treatment during myocarditis completely prevented post-inflammatory fibrosis, T cell relapse and left ventricular dysfunction. Mechanistically, M-CSF-induced macrophage differentiation from prominin-1+ progenitors critically required nitric oxide synthase 2. Accordingly, M-CSF treatment failed to reduce myocardial fibrosis development in Nos2-/- mice. Conclusions: Altering the in vivo fate of inflammatory prominin-1 expressing progenitors from pro-fibrotic into the F4/80 expressing macrophage phenotype protects from myocarditis progression, cardiac fibrosis, and heart failure. These findings offer a modern therapeutic model and challenge former concepts, which attributed macrophages a detrimental role in inflammatory cardiomyopathy progression.

Rôle de l'IRM cardiaque dans le dépistage des cardiomyopathies de l'adulte [Cardiomyopathy and cardiac magnetic resonance].

Cardiovascular magnetic resonance (CMR) is a rapidly emerging non-invasive imaging technique free of X-Ray and offers higher spatial resolution than alternative forms of cardiac imaging for the assessment of left ventricular (LV) anatomy, function, and viability due to the unique capability of myocardial tissue characterization after gadolinium-chelates contrast administration. This imaging technique has clinical utility over a broad spectrum of heart diseases: ranging from ischaemic to non ischaemic aetiologies. Cardiomyopathies (CMP) are a heterogeneous group of diseases of the myocardium associated with architectural abnormalities and mechanical dysfunction. CMR can help excluding coronary artery disease and can provide positive diagnostic features for several CMP resulted in better diagnosis and management, Leading to improvements in mortality.

IRM cardiaque dans le suivi des cardiopathies congénitales à l'âge adulte [Cardiac MRI in the follow-up of adult congenital cardiomyopathy patients].

Magnetic resonance imaging is a rapidly developing modality in cardiology. It offers an excellent image definition and a large field of view, allowing a more accurate morphological assessment of cardiac malformations. Due to its unique versatility and its ability to provide myocardial tissue characterization, cardiac magnetic resonance (CMR) is now recognized as a central imaging modality for a wide range of congenital heart diseases, including assessment of post-surgical cardiac anatomy, quantification of valvular disease and detection of myocardial ischemia. CMR provides useful diagnostic information without any radiation exposure, and improves the global management of patients with congenital heart disease.

Familial aplasia of the trapezius muscle: clinical and MRI findings.

A 5-year-old boy was referred to our neurology clinic for suspected myopathy. His parents reported normal upper extremity strength and no limitation in daily activities; however, he was unable to raise his arms above his head. On examination, both shoulders were down-slanting and anteriorly displaced, leading to a webbed neck appearance. Muscle MRI demonstrated isolated bilateral aplasia of the trapezius muscles. His father was found to have a unilateral partial trapezius hypoplasia with no functional consequences. Conclusion:  Congenital aplasia of the trapezius muscle is a rare condition; bilateral aplasia of the muscle, having been reported in only five cases, is most often associated with aplasia of the pectoralis major. This is the first report to our knowledge to demonstrate bilateral isolated trapezius aplasia by MRI.

The AP-1 transcription factor c-Jun prevents stress-imposed maladaptive remodeling of the heart.

Systemic hypertension increases cardiac workload and subsequently induces signaling networks in heart that underlie myocyte growth (hypertrophic response) through expansion of sarcomeres with the aim to increase contractility. However, conditions of increased workload can induce both adaptive and maladaptive growth of heart muscle. Previous studies implicate two members of the AP-1 transcription factor family, junD and fra-1, in regulation of heart growth during hypertrophic response. In this study, we investigate the function of the AP-1 transcription factors, c-jun and c-fos, in heart growth. Using pressure overload-induced cardiac hypertrophy in mice and targeted deletion of Jun or Fos in cardiomyocytes, we show that c-jun is required for adaptive cardiac hypertrophy, while c-fos is dispensable in this context. c-jun promotes expression of sarcomere proteins and suppresses expression of extracellular matrix proteins. Capacity of cardiac muscle to contract depends on organization of principal thick and thin filaments, myosin and actin, within the sarcomere. In line with decreased expression of sarcomere-associated proteins, Jun-deficient cardiomyocytes present disarrangement of filaments in sarcomeres and actin cytoskeleton disorganization. Moreover, Jun-deficient hearts subjected to pressure overload display pronounced fibrosis and increased myocyte apoptosis finally resulting in dilated cardiomyopathy. In conclusion, c-jun but not c-fos is required to induce a transcriptional program aimed at adapting heart growth upon increased workload.

Immunopathology of cardiomyopathy in the experimental Chagas disease

The mechanisms by which Trypanosoma cruzi causes cardiomyopathy and induces neuronal destruction are discussed in this paper. The results suggest that autoimmunity in the chronic phase is the main cause of the progressive cardiac destruction, and that autoreactivity is restricted to the CD4+ T cell compartment. During the acute phase, the neuronal and cardiac fiber destruction occurs when ruptured parasite nests release T. cruzi antigens that bind to the cell surface in the vicinity which become targets for the cellular and humoral immune response against T. cruzi. The various factors involved in the genesis of autoimmunity in chronic T. cruzi infection include molecular mimicry, presentation of self-antigens and imbalance of immune regulation.