940 resultados para Munchausen Syndrome by proxy


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Hyaline fibromatosis syndrome is an autosomal recessive disease caused by mutations in ANTXR2, a gene involved in extracellular matrix homeostasis. Sixty percent of patients carry frameshift mutations at a mutational hotspot in exon 13. We show in patient cells that these mutations lead to low ANTXR2 mRNA and undetectable protein levels. Ectopic expression of the proteins encoded by the mutated genes reveals that a two base insertion leads to the synthesis of a protein that is rapidly targeted to the ER-associated degradation pathway due to the modified structure of the cytosolic tail, which instead of being hydrophilic and highly disordered as in wild type ANTXR2, is folded and exposes hydrophobic patches. In contrast, one base insertion leads to a truncated protein that properly localizes to the plasma membrane and retains partial function. We next show that targeting the nonsense mediated mRNA decay pathway in patient cells leads to a rescue of ANTXR2 protein in patients carrying one base insertion but not in those carrying two base insertions. This study highlights the importance of in-depth analysis of the molecular consequences of specific patient mutations, which even when they occur at the same site can have drastically different consequences.

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Tourette syndrome is a childhood-onset neuropsychiatric disorder with a high prevalence of attention deficit hyperactivity and obsessive-compulsive disorder co-morbidities. Structural changes have been found in frontal cortex and striatum in children and adolescents. A limited number of morphometric studies in Tourette syndrome persisting into adulthood suggest ongoing structural alterations affecting frontostriatal circuits. Using cortical thickness estimation and voxel-based analysis of T1- and diffusion-weighted structural magnetic resonance images, we examined 40 adults with Tourette syndrome in comparison with 40 age- and gender-matched healthy controls. Patients with Tourette syndrome showed relative grey matter volume reduction in orbitofrontal, anterior cingulate and ventrolateral prefrontal cortices bilaterally. Cortical thinning extended into the limbic mesial temporal lobe. The grey matter changes were modulated additionally by the presence of co-morbidities and symptom severity. Prefrontal cortical thickness reduction correlated negatively with tic severity, while volume increase in primary somatosensory cortex depended on the intensity of premonitory sensations. Orbitofrontal cortex volume changes were further associated with abnormal water diffusivity within grey matter. White matter analysis revealed changes in fibre coherence in patients with Tourette syndrome within anterior parts of the corpus callosum. The severity of motor tics and premonitory urges had an impact on the integrity of tracts corresponding to cortico-cortical and cortico-subcortical connections. Our results provide empirical support for a patho-aetiological model of Tourette syndrome based on developmental abnormalities, with perturbation of compensatory systems marking persistence of symptoms into adulthood. We interpret the symptom severity related grey matter volume increase in distinct functional brain areas as evidence of ongoing structural plasticity. The convergence of evidence from volume and water diffusivity imaging strengthens the validity of our findings and attests to the value of a novel multimodal combination of volume and cortical thickness estimations that provides unique and complementary information by exploiting their differential sensitivity to structural change.

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INTRODUCTION We functionally analyzed a frameshift mutation in the SCN5A gene encoding cardiac Na(+) channels (Nav1.5) found in a proband with repeated episodes of ventricular fibrillation who presented bradycardia and paroxysmal atrial fibrillation. Seven relatives also carry the mutation and showed a Brugada syndrome with an incomplete and variable expression. The mutation (p.D1816VfsX7) resulted in a severe truncation (201 residues) of the Nav1.5 C-terminus. METHODS AND RESULTS Wild-type (WT) and mutated Nav1.5 channels together with hNavβ1 were expressed in CHO cells and currents were recorded at room temperature using the whole-cell patch-clamp. Expression of p.D1816VfsX7 alone resulted in a marked reduction (≈90%) in peak Na(+) current density compared with WT channels. Peak current density generated by p.D1816VfsX7+WT was ≈50% of that generated by WT channels. p.D1816VfsX7 positively shifted activation and inactivation curves, leading to a significant reduction of the window current. The mutation accelerated current activation and reactivation kinetics and increased the fraction of channels developing slow inactivation with prolonged depolarizations. However, late INa was not modified by the mutation. p.D1816VfsX7 produced a marked reduction of channel trafficking toward the membrane that was not restored by decreasing incubation temperature during cell culture or by incubation with 300 μM mexiletine and 5 mM 4-phenylbutirate. CONCLUSION Despite a severe truncation of the C-terminus, the resulting mutated channels generate currents, albeit with reduced amplitude and altered biophysical properties, confirming the key role of the C-terminal domain in the expression and function of the cardiac Na(+) channel.

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Liddle's syndrome is a monogenic form of hypertension caused by mutations in the PY motif of the COOH terminus of beta- and gamma-epithelial Na+ channel (ENaC) subunits. These mutations lead to retention of active channels at the cell surface. Because of the critical role of this PY motif in the stability of ENaCs at the cell surface, we have investigated its contribution to the ENaC response to aldosterone and vasopressin. Mutants of the PY motif in beta- and gamma-ENaC subunits (beta-Y618A, beta-P616L, beta-R564stop, and gamma-K570stop) were stably expressed by retroviral gene transfer in a renal cortical collecting duct cell line (mpkCCDcl4), and transepithelial Na+ transport was assessed by measurements of the benzamil-sensitive short-circuit current (Isc). Cells that express ENaC mutants of the PY motif showed a five- to sixfold higher basal Isc compared with control cells and responded to stimulation by aldosterone (10(-6) M) or vasopressin (10(-9) M) with a further increase in Isc. The rates of the initial increases in Isc after aldosterone or vasopressin stimulation were comparable in cells transduced with wild-type and mutant ENaCs, but reversal of the effects of aldosterone and vasopressin was slower in cells that expressed the ENaC mutants. The conserved sensitivity of ENaC mutants to stimulation by aldosterone and vasopressin together with the prolonged activity at the cell surface likely contribute to the increased Na+ absorption in the distal nephron of patients with Liddle's syndrome.

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Human immunodeficiency virus (HIV)-positive patients have a greater prevalence of coinfection with human papillomavirus (HPV) is of high oncogenic risk. Indeed, the presence of the virus favours intraepithelial squamous cell lesion progression and may induce cancer. The aim of this study was to evaluate the prevalence of HPV infection, distribution of HPV types and risk factors among HIV-positive patients. Cervical samples from 450 HIV-positive patients were analysed with regard to oncotic cytology, colposcopy and HPV presence and type by means of polymerase chain reaction and sequencing. The results were analysed by comparing demographic data and data relating to HPV and HIV infection. The prevalence of HPV was 47.5%. Among the HPV-positive samples, 59% included viral types of high oncogenic risk. Multivariate analysis showed an association between HPV infection and the presence of cytological alterations (p = 0.003), age greater than or equal to 35 years (p = 0.002), number of partners greater than three (p = 0.002), CD4+ lymphocyte count < 200/mm3 (p = 0.041) and alcohol abuse (p = 0.004). Although high-risk HPV was present in the majority of the lesions studied, the low frequency of HPV 16 (3.3%), low occurrence of cervical lesions and preserved immunological state in most of the HIV-positive patients were factors that may explain the low occurrence of precancerous cervical lesions in this population.

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Altered serine protease activity is associated with skin disorders in humans and in mice. The serine protease channel-activating protease-1 (CAP1; also termed protease serine S1 family member 8 (Prss8)) is important for epidermal homeostasis and is thus indispensable for postnatal survival in mice, but its roles and effectors in skin pathology are poorly defined. In this paper, we report that transgenic expression in mouse skin of either CAP1/Prss8 (K14-CAP1/Prss8) or protease-activated receptor-2 (PAR2; Grhl3(PAR2/+)), one candidate downstream target, causes epidermal hyperplasia, ichthyosis and itching. K14-CAP1/Prss8 ectopic expression impairs epidermal barrier function and causes skin inflammation characterized by an increase in thymic stromal lymphopoietin levels and immune cell infiltrations. Strikingly, both gross and functional K14-CAP1/Prss8-induced phenotypes are completely negated when superimposed on a PAR2-null background, establishing PAR2 as a pivotal mediator of pathogenesis. Our data provide genetic evidence for PAR2 as a downstream effector of CAP1/Prss8 in a signalling cascade that may provide novel therapeutic targets for ichthyoses, pruritus and inflammatory skin diseases.

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Vitamin D deficiency is associated with higher cardiovascular risk and metabolic syndrome (MeS) criteria. The main objective of this study was to analyse the association of 25-hydroxyvitamin D (25-OHD) serum levels with MeS (National Cholesterol Education Program-Adult Treatment Panel-III criteria) in 46 Spanish patients with psoriasis, but without arthritis and systemic treatment, and 46 control subjects, matched by sex and age. The patients with psoriasis showed significantly lower level of 25-OHD than controls (30.5 vs. 38.3 ng/ml; p = 0.0001). Patients with MeS had significantly lower serum levels of 25-OHD than those without MeS (24.1 ± 7.5 vs. 32.8 ± 8.9, p = 0.007), and a negative correlation was found between 25-OHD and waist circumference, diastolic blood pressure, fasting glucose, and triglyceridaemia. In the control group no significant correlation between 25-OHD and MeS was found. Al-though the sample was small, our results suggest a potential protective role for 25-OHD in the metabolic profile of patients with psoriasis without arthritis.

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Sirenomelia, also called the mermaid syndrome is a severe malformation involving multiple organs and characterized by partially or completely developed lower extremities fused by the skin. The birth of a "mermaid" is very rare (1.2-4.2 cases for 100,000 births); most are stillborn, or die at or shortly after birth. The case of a living female neonate with dipodic simelia (fusion of well-developed legs) is presented. No prenatal diagnosis was made and the newborn had an uneventful neonatal course following Cesarean section delivery. The complex and striking malformation was obvious at birth and further evaluation revealed very poorly functioning kidneys, associated with abnormal anorectum, urogenital tract, and external genitalia, as well as a pelvic malformation. Supportive care was applied because of the poor prognosis and the child died at 7 weeks of age, due to renal failure.

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A 49-year-old woman, without known cardiovascular risk factors. Hoarseness of voice caused by a paralysis of left vocal cord. She was admitted to hospital because of acute coronary syndrome, associated to resuscitated cardiac arrest (asystolia documented) without later neurology sequels. Physical examination was anodyne. Echocardiographic study demonstrated a compatible image with a large left sinus of Valsalva aneurysm (SVA) (Panel A) and mild aortic regurgitation. Cardiac catheterization confirmed the presence of left SVA (Panel B) that produced extrinsic compression of the left main coronary artery (Panels C and D). Repair surgery was made by means of closing the aneurysmal orifice with a patch of dacron. Intra-operatory echocardiographic control study found severe aortic regurgitation, so valvular replacement with 19 mm mechanical prosthesis and extension of the valve annulus with patch of dacron was performed, associated with bypass with safena vein graft to left coronary artery. SVA is a very infrequent cardiac anomaly, generally with silent clinical course until it ruptures. Myocardial ischaemia caused by coronary artery compression is unusual. We described the case of a patient diagnosed of left SVA, whose initial clinical manifestation was the appearance of resuscitated sudden cardiac death in the context of an acute coronary syndrome.

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OBJECTIVES: Acute respiratory distress syndrome is a common and highly lethal inflammatory lung syndrome. We previously have shown that an adenoviral vector expressing the heat shock protein (Hsp)70 (AdHSP) protects against experimental sepsis-induced acute respiratory distress syndrome in part by limiting neutrophil accumulation in the lung. Neutrophil accumulation and activation is modulated, in part, by the nuclear factor-kappaB (NF-kappaB) signal transduction pathway. NF-kappaB activation requires dissociation/degradation of a bound inhibitor, IkappaBalpha. IkappaBalpha degradation requires phosphorylation by IkappaB kinase, ubiquitination by the SCFbeta-TrCP (Skp1/Cullin1/Fbox beta-transducing repeat-containing protein) ubiquitin ligase, and degradation by the 26S proteasome. We tested the hypothesis that Hsp70 attenuates NF-kappaB activation at multiple points in the IkappaBalpha degradative pathway. DESIGN: Laboratory investigation. SETTING: University medical center research laboratory. SUBJECTS: Adolescent (200 g) Sprague-Dawley rats and murine lung epithelial-12 cells in culture. INTERVENTIONS: Lung injury was induced in rats via cecal ligation and double puncture. Thereafter, animals were treated with intratracheal injection of 1) phosphate buffer saline, 2) AdHSP, or 3) an adenovirus expressing green fluorescent protein. Murine lung epithelial-12 cells were stimulated with tumor necrosis factor-alpha and transfected. NF-kappaB was examined using molecular biological tools. MEASUREMENTS AND MAIN RESULTS: Intratracheal administration of AdHSP to rats with cecal ligation and double puncture limited nuclear translocation of NF-kappaB and attenuated phosphorylation of IkappaBalpha. AdHSP treatment reduced, but did not eliminate, phosphorylation of the beta-subunit of IkappaB kinase. In vitro kinase activity assays and gel filtration chromatography revealed that treatment of sepsis-induced lung injury with AdHSP induced fragmentation of the IkappaB kinase signalosome. This stabilized intermediary complexes containing IkappaB kinase components, IkappaBalpha, and NF-kappaB. Cellular studies indicate that although ubiquitination of IkappaBalpha was maintained, proteasomal degradation was impaired by an indirect mechanism. CONCLUSIONS: Treatment of sepsis-induced lung injury with AdHSP limits NF-kappaB activation. This results from stabilization of intermediary NF-kappaB/IkappaBalpha/IkappaB kinase complexes in a way that impairs proteasomal degradation of IkappaBalpha. This novel mechanism by which Hsp70 attenuates an intracellular process may be of therapeutic value.

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22q11.2 deletion syndrome (22q11.2DS) is a common genetic condition associated with cognitive and learning impairments. In this study, we applied a three-dimensional method for quantifying gyrification at thousands of points over the cortical surface to imaging data from 44 children, adolescents, and young adults with 22q11.2DS (17 males, 27 females; mean age 17y 2mo [SD 9y 1mo], range 6-37y), and 53 healthy participants (21 males, 32 females; mean age 15y 4mo [SD 8y 6mo]; range 6-40y). Several clusters of reduced gyrification were observed, further substantiating the pattern of cerebral alterations presented by children with the syndrome. Comparisons within 22q11.2DS demonstrated an effect of congenital heart disease (CHD) on cortical gyrification, with reduced gyrification at the parieto-temporo-occipital junction in patients with CHD, as compared with patients without CHD. Reductions in gyrification can resemble mild polymicrogyria, suggesting early abnormal neuronal proliferation or migration and providing support for an effect of hemodynamic factors on brain development in 22q11.2DS. The results also shed light on the pathophysiology of acquired brain injury in other populations with CHD.

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BACKGROUND Fragile X syndrome (FXS) is an inherited neurodevelopmental condition characterised by behavioural, learning disabilities, physical and neurological symptoms. In addition, an important degree of comorbidity with autism is also present. Considered a rare disorder affecting both genders, it first becomes apparent during childhood with displays of language delay and behavioural symptoms.Main aim: To show whether the combination of 10 mg/kg/day of ascorbic acid (vitamin C) and 10 mg/kg/day of α-tocopherol (vitamin E) reduces FXS symptoms among male patients ages 6 to 18 years compared to placebo treatment, as measured on the standardized rating scales at baseline, and after 12 and 24 weeks of treatment.Secondary aims: To assess the safety of the treatment. To describe behavioural and cognitive changes revealed by the Developmental Behaviour Checklist Short Form (DBC-P24) and the Wechsler Intelligence Scale for Children-Revised. To describe metabolic changes revealed by blood analysis. To measure treatment impact at home and in an academic environment. METHODS/DESIGN A phase II randomized, double-blind pilot clinical trial. SCOPE male children and adolescents diagnosed with FXS, in accordance with a standardized molecular biology test, who met all the inclusion criteria and none of the exclusion criteria. INSTRUMENTATION clinical data, blood analysis, Wechsler Intelligence Scale for Children-Revised, Conners parent and teacher rating scale scores and the DBC-P24 results will be obtained at the baseline (t0). Follow up examinations will take place at 12 weeks (t1) and 24 weeks (t2) of treatment. DISCUSSION A limited number of clinical trials have been carried out on children with FXS, but more are necessary as current treatment possibilities are insufficient and often provoke side effects. In the present study, we sought to overcome possible methodological problems by conducting a phase II pilot study in order to calculate the relevant statistical parameters and determine the safety of the proposed treatment. The results will provide evidence to improve hyperactivity control and reduce behavioural and learning problems using ascorbic acid (vitamin C) and α-tocopherol (vitamin E). The study protocol was approved by the Regional Government Committee for Clinical Trials in Andalusia and the Spanish agency for drugs and health products. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01329770 (29 March 2011).

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Background. Hamstring injuries continue to affect active individuals and although inadequate muscle extensibility remains a commonly accepted factor, little is known about the most effective method to improve flexibility. Purpose. To determine if an isolated neurodynamic sciatic sliding technique would improve hamstring flexibility to a greater degree than stretching or a placebo intervention in asymptomatic subjects with short hamstring syndrome (SHS). Study Design. Randomized double-blinded controlled trial. Methods. One hundred and twenty subjects with SHS were randomized to 1 of 3 groups: neurodynamic sliding, hamstring stretching, and placebo control. Each subject's dominant leg was measured for straight leg raise (SLR) range of motion (ROM) before and after interventions. Data were analyzed with a 3 × 2 mixed model ANOVA followed by simple main effects analyses. Results. At the end of the study, more ROM was observed in the Neurodynamic and Stretching groups compared to the Control group and more ROM in the Neurodynamic group compared to Stretching group. Conclusion. Findings suggest that a neurodynamic sliding technique will increase hamstring flexibility to a greater degree than static hamstring stretching in healthy subjects with SHS. Clinical Relevance. The use of neurodynamic sliding techniques to improve hamstring flexibility in sports may lead to a decreased incidence in injuries; however, this needs to be formally tested.

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BACKGROUND Tapia's syndrome is an uncommon disease described in 1904 by Antonio Garcia Tapia, a Spanish otolaryngologist. It is characterized by concomitant paralysis of the hypoglossal (XIIth) and pneumogastric (Xth) nerves. Only 69 cases have been described in the literature. Typically, the reported patients presented with a history of orotracheal intubation. Common symptoms are dysphonia, tongue deviation toward the affected side, lingual motility disturbance, and swallowing difficulty. CASE PRESENTATION In the report, we describe three cases of Tapia's syndrome in three Caucasian patients who underwent surgery with general anesthesia. Two of these patients underwent neck abscess drainage, and the third had an open reduction of a shoulder fracture. The clinical symptoms of Tapia's syndrome appeared after extubation. All three of our patients recovered their lost function at 3 months after diagnosis. CONCLUSIONS We underline the importance of performing airway endoscopy and a specific program of swallowing rehabilitation for the proper management of Tapia's syndrome.

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Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome, which is characterized by cleft palate and severe defects of the skin, is an autosomal dominant disorder caused by mutations in the gene encoding transcription factor p63. Here, we report the generation of a knock-in mouse model for AEC syndrome (p63(+/L514F) ) that recapitulates the human disorder. The AEC mutation exerts a selective dominant-negative function on wild-type p63 by affecting progenitor cell expansion during ectodermal development leading to a defective epidermal stem cell compartment. These phenotypes are associated with impairment of fibroblast growth factor (FGF) signalling resulting from reduced expression of Fgfr2 and Fgfr3, direct p63 target genes. In parallel, a defective stem cell compartment is observed in humans affected by AEC syndrome and in Fgfr2b(-/-) mice. Restoring Fgfr2b expression in p63(+/L514F) epithelial cells by treatment with FGF7 reactivates downstream mitogen-activated protein kinase signalling and cell proliferation. These findings establish a functional link between FGF signalling and p63 in the expansion of epithelial progenitor cells and provide mechanistic insights into the pathogenesis of AEC syndrome.