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21.
Previous studies have suggested that corticotropin-releasing factor (CRF) has immunoregulatory effects in addition to its neuroendocrine role. We examined the ability of CRF to inhibit lipopolysaccharide (LPS)-induced pulmonary vascular leak in vivo. Female BALB/C mice were treated with either normal saline (NS) or CRF prior to injection with LPS. Pulmonary vascular leak was inhibited by CRF as assessed by measurement of lung wet-to-dry ratios. The stress-induced increase in serum corticosterone levels in mice injected with LPS alone was not further increased by treatment with CRF. This indicates that the effect of CRF was not mediated centrally by stimulation of endogenous steroid release. Histologic examination of the lungs revealed that leukocyte infiltration was significantly depressed in CRF-treated mice thus confirming the protective effect of CRF. In addition, a modest prolongation of survival was demonstrated in CRF-treated mice following challenge with LPS (p=.08). These data indicate the potential utility of CRF as a modulator of pulmonary vascular leak.  相似文献   
22.
Primary dystonia is a disorder of movement for which no consistent pathophysiology has been identified; in the absence of evidence to the contrary, it is assumed to be cognitively benign. We have studied a clinically heterogeneous group of 14 patients with primary dystonia on a battery of neuropsychological tests. Despite well-preserved speed of information processing, language, spatial, memory and general intellectual skills relative to normal controls, we have identified a constellation of attentional-executive cognitive deficits on the Cambridge Neuropsychological Test Automated Battery (CANTAB). Specifically, patients demonstrated significant difficulties negotiating the extra-dimensional set-shifting phase of the IED task. The implications of these findings for the pathophysiology of primary dystonia are discussed. This is, to the best of our knowledge, the first report of a significant cognitive deficit in patients with primary dystonia.  相似文献   
23.
We report a case of cervical dystonia occurring in a 33-year-old without personal history of movement disorder but with family history of essential tremor, primigravid, primiparous woman at 1 weeks' amenorrhea, resolved completely after delivery in the course of 3 months. Dystonia never recurred in the following 5 years. Several neurological disorders are known to occur or worsen during pregnancy. As far as we know, this is the second reported case of dystonia occurring during pregnancy, thus confirming that dystonia gravidarum represents a new entity and should be considered in women of reproductive age affected by dystonia, especially when presenting with rapid-onset cervical dystonia.  相似文献   
24.
Status dystonicus (SD) is a life threatening disorder that develops in patients with both primary and secondary dystonia, characterized by acute worsening of symptoms with generalized and severe muscle contractions. To date, no information is available on the best way to treat this disorder. We review the previously described cases of SD and two new cases are reported, one of which occurring in a child with static encephalopathy, and the other one in a patient with pantothenate kinase-associated neurodegeneration. Both patients were admitted to an intensive care unit and treated with midazolam and propofol. This approach proved to be useful in the former while the progressive nature of the dystonia of the second patient required the combination of intrathecal baclofen infusion and bilateral pallidal deep brain stimulation. We believe that a rapid and aggressive approach is justified to avoid the great morbidity and mortality which characterize SD. Our experience, combined with the data available in the literature, might permit to establish the best strategies in managing this rare and severe condition.  相似文献   
25.
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
26.
27.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.  相似文献   
28.
The content of dolichol, an isoprenoid present in all biological membranes, was determined in isolated sinusoidal liver cells after treatment of rats for 2 and 4 months with a low dosage of the hepatotoxin thioacetamide. The significant decrease in dolichol observed in hepatocytes after 2 months might be explained by peroxidation of the isoprenoid. At the same time point, retinol was retained, and decreased only after 4 months of treatment. After 4 months of treatment therefore both lipids decreased. In a subfraction of hepatic stellate cells, Ito-1 cells, the main storage site of vitamin A, dolichol decreased significantly only after 4 months. A remarkable difference from hepatocytes is that in Ito-1 cells retinol content significantly decreased after 2 months of treatment. In another subfraction, Ito-2 cells, the content of the two isoprenoids decreased in parallel. This heterogeneous subfraction might represent those transitional hepatic stellate cells that, while losing retinol, are in the process of differentiating into myofibroblasts secreting extracellular matrix components. In Kupffer cells and sinusoidal endothelial cells, impairment of dolichol might be observed later, only after 4 months of treatment, while retinol decreases uniformly over time. Starting after two months of treatment, the decrease of dolichol and the increase of retinol in hepatocytes, at the same time as retinol decreases in hepatic stellate cells, might be taken as an early index of incipient liver injury due to thioacetamide. This hypothesis is discussed with regard to a role of dolichol in the modulation of membrane fluidity for intracellular and intercellular retinol transport.  相似文献   
29.
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.  相似文献   
30.
Zusammenfassung Anamnese und Diagnostik: Ein 75-jähriger Patient wies neben unspezifischen anamnestischen Symptomen (Appetitverlust, Merkfähigkeitsstörung und Muskelschwäche) klinisch diskrete Beinödeme, abgeschwächte Muskeleigenreflexe und eine deutliche Gedächtnisstörung auf. Aufgrund einer euvolämischen, laborchemisch hypoosmolaren Hypoatriämie und eines Urinnatriums im Normbereich wurde als Arbeitsdiagnose von einem Syndrom der inadäquaten ADH-Sekretion (SIADH) ausgegangen. Während sich weder in der Anamnese noch in den folgenden Untersuchungen eine dem SIADH zugrunde liegende Pathologie eruieren ließ, ergab sich in den weiteren Laboruntersuchungen der Befund einer ausgeprägten Hypothyreose. Die Hyponatriämie bei Hypothyreose spiegelt eine Komponente der renalen Funktionsstörung bei Schilddrüsenhormonmangel wider. Therapie und Verlauf: Nach Flüssigkeitsrestriktion und Hormonsubstitution erreichte der Patient schnell normale Natriumwerte und zeigte eine deutliche Besserung seiner kognitiven Fähigkeiten. Schlussfolgerung: Als Schlussfolgerung aus dieser Kasuistik wird Zurückhaltung bei der Diagnose eines SIADH empfohlen, bevor nicht eine sorgfältige Untersuchung des Nebennieren- und Schilddrüsenhormonstatus erfolgt ist. Abstract Case History and Diagnosis: A 75-year-old male patient presented with a history of anorexia, muscle weakness, and increasing memory loss. He had mild pedal edema and decreased deep tendon reflexes. As the laboratory tests showed hypoosmolar hyponatremia and urinary sodium within the normal range, a syndrome of inappropriate ADH secretion (SIADH) was presumed. While neither the medical history nor any of the diagnostic procedures revealed any underlying pathology explaining the SIADH, laboratory tests showed significant hypothyroidism. Hypothyroid states are associated with significant changes in renal function, one of which is hypoosmolar hyponatremia. Treatment and Course: Treatment included fluid restriction and hormone substitution and resulted in a quick correction of the hyponatremia and a clear improvement of the patient's cognitive function. Conclusion: It is concluded that the diagnosis of SIADH should only be made after thorough investigation of the adrenal and thyroid hormone status.  相似文献   
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