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91.
Isolated congenital heart block (ICHB) is frequently associated with neonatal lupus syndrome (NLS). Therefore few data are available regarding the long-term cardiac outcome of newborns with ICHB and the pathogenic mechanisms are not yet defined. In order to compare demographic features and cardiological outcome of patients with ICHB submitted to pacemaker (PM) implantation with and without NLS, forty ICHB patients were evaluated pre- and post-PM implantation, by clinical, electrocardiogram, Holter Monitoring, treadmill test, and electrophysiological study. According to the presence of antibodies to 52 and 60 kDa Ro/SSA and La/SSB proteins in mother's sera, it was found that 60% (24/40) of patients had ICHB associated to NLS (ICHB/NL+). Twenty-three of 24 ICHB/NL+ patients were asymptomatic, and 16 (67%) were female (P = 0.013). The frequency of syncope, mitral insufficiency (MI), and congestive heart failure (CHF) was similar pre-PM implantation in both ICHB/NL+ and ICHB/NL- groups (P > 0.05). After PM implantation, MI and CHF were only observed in ICHB/NL+ patients, although not statistically significant. Interestingly, 67% of ICHB/NL+ were noticed before one year of age while only one fourth of ICHB/NL- was diagnosed in this period (P = 0.024). Almost half (46%) of ICHB/NL+ patients required PMs in the first 24 months of life, whereas only one in the ICHB/NL- received a PM at the same age (P = 0.02). In ICHB patients requiring PM implantation, the antibody-mediated lesion seems to be associated with an earlier onset and a more severe heart disease, in spite of the uniform criteria for PM indication.  相似文献   
92.
We have investigated the influences of gamma interferon (IFN-gamma) and interleukin-12 (IL-12) on the efficacy of posaconazole (POS) treatment of acute experimental infections with Trypanosoma cruzi; the standard drug, benznidazole (BZ), was used as a positive control. Wild-type (WT) mice infected with T. cruzi and treated with POS or BZ had no parasitemia, 100% survival, and cure rates of 86 to 89%. IFN-gamma-knockout (KO) mice infected with T. cruzi and treated with BZ controlled the infection during treatment but relapsed after the drug pressure ceased and had 0% survival, while those receiving POS better controlled the infection after the end of treatment and had 70% survival (P<0.0001 compared to the results for both untreated and BZ-treated animals). IL-12-KO mice infected and treated with POS or BZ had intermediate results, displaying enhanced parasitemia, decreased survival (77 to 83%), and reduced cure rates (35 to 39%) compared with those of the WT animals. Our results demonstrate that either IFN-gamma or IL-12 deficiency reduces the efficacy of POS or BZ in this experimental model but also indicate that the anti-T. cruzi activity of POS is much less dependent on the activity of IFN-gamma than that of BZ is.  相似文献   
93.
Despite the development of efficient boar semen extenders, there is still room for improvement of new formulas using new molecules that could increase fertilisation outcomes and substitute cryoprotectants and antibiotics. The goal of this work was to evaluate if the essential oils from the leaves of Myrrhinium atropurpureum and Cymbopogon citratus are suitable as additives in boar semen extender. The major compounds found in the essential oils from M. atropurpureum were 1,8‐cineole (37.37%) and terpinolene (19.18%); and geranial (49.8%) and neral (33.24%) in essential oil of Ccitratus. The addition of 1% and 0.1% of both essential oils to extended semen had immediate spermicidal effects (< 0.05). Lower concentrations were tested and no cytotoxic effect was observed when M. atropurpureum essential oil was added at 0.001%. Differently, essential oil from Ccitratus reduced sperm motility, membrane functionality and integrity and mitochondrial membrane potential even in concentrations as low as 0.001%. Also, addition of essential oils in low concentrations had no inhibitory effect against Escherichia coli and Pseudomonas aeruginosa growth. We conclude that the essential oils from C. citratus and M. atropurpureum, rich in monoterpenes, are cytotoxic to swine spermatozoa, therefore unsuitable as semen extender additives.  相似文献   
94.
The prevalence of osteoporosis is expected to increase with the ageing of the world's population. This article reviews the epidemiology, risk factors and health burden of osteoporosis. In the Global Burden of Disease (GBD) Study 2005, osteoporosis is studied as a risk factor for fracture by considering the bone-mineral-density (BMD) measurement as the continuous exposure variable. We have performed a systematic review seeking population-based studies with BMD data measured by dual-X-ray absorptiometry (DXA). The femoral neck was selected as the unique location and all values were converted into Hologic(?) to enable inclusion of worldwide data for analysis. Provisional results on mean BMD values for different world regions are shown in age breakdowns for males and females 50 years or over, as well as mean T-scores using the young, white, female reference of National Health and Nutrition Examination Survey (NHANES) III. Results show remarkable geographical differences and a time trend towards improvement of the BMD values in Asian and European populations.  相似文献   
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Epidural motor cortex stimulation (MCS) has been used for treating patients with neuropathic pain resistant to other therapeutic approaches. Experimental evidence suggests that the motor cortex is also involved in the modulation of normal nociceptive response, but the underlying mechanisms of pain control have not been clarified yet. The aim of this study was to investigate the effects of epidural electrical MCS on the nociceptive threshold of naive rats. Electrodes were placed on epidural motor cortex, over the hind paw area, according to the functional mapping accomplished in this study. Nociceptive threshold and general activity were evaluated under 15-min electrical stimulating sessions. When rats were evaluated by the paw pressure test, MCS induced selective antinociception in the paw contralateral to the stimulated cortex, but no changes were noticed in the ipsilateral paw. When the nociceptive test was repeated 15 min after cessation of electrical stimulation, the nociceptive threshold returned to basal levels. On the other hand, no changes in the nociceptive threshold were observed in rats evaluated by the tail-flick test. Additionally, no behavioral or motor impairment were noticed in the course of stimulation session at the open-field test. Stimulation of posterior parietal or somatosensory cortices did not elicit any changes in the general activity or nociceptive response. Opioid receptors blockade by naloxone abolished the increase in nociceptive threshold induced by MCS. Data shown herein demonstrate that epidural electrical MCS elicits a substantial and selective antinociceptive effect, which is mediated by opioids.  相似文献   
99.
The Dandy-Walker syndrome (DWS) is a rare posterior fossa malformation. The DWS can occur associated with other brain or systemic malformations, but ocular abnormalities in this disease are rare and clinical findings mimicking myasthenia gravis have not been described to date. We report a 23-year-old woman who presented mild limitation of the ocular movements with progressive palpebral ptosis, which changed in intensity during the day. The investigation showed negative anti-acetylcholine receptor antibody, repetitive nerve stimulation and "Tensilon test", but the brain magnetic resonance image reveals DWS with hydrocephalus associated with callosal dysgenesis. The characteristic of disease, clinical manifestations and pathologic features, specially the clinical evaluation of ocular abnormalities in suspicion of DWS, including the MG in differential diagnosis are discussed.  相似文献   
100.
Rippling muscle disease (RMD) is a benign myopathy with symptoms and signs of muscular hyperirritability. We report a 17-year-old patient who presented with muscular hypertrophy, local mounding on percussion, and a rippling phenomenon. Needle electromyography showed electrical silence during the rippling phenomenon. Muscle protein immunohistochemical analysis showed a partial deficiency of caveolin-3. Molecular analysis revealed a novel heterozygous A>C transition at nucleotide position 140 in exon 2 of the caveolin-3 gene. We associated this novel mutation with RMD.  相似文献   
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