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81.
Summary Cultures of fetal aoudad sheep kidney (FAK), bovine embryonic lung (BEL), and African green monkey kidney (Vero) cells were compared for differential replication of alcelaphine herpesviruses. Cell-free virus appears more rapidly when infected cells are incubated at 33° C rather than at 37° C. Events in the replication and morphologic development of several alcelaphine herpesvirus isolates have been documented using light and electron microscopy. Techniques for indirect immunofluorescence and serum virus neutralization are described. When virus free of host-cell contaminants is desired for biochemical analysis, virus isolates are initially purified on sucrose gradients and then further purified by density gradient centrifugation in Percoll.  相似文献   
82.
This study was designed to compare the antidepressant effects of alprazolam and amitriptyline in a group of 30 inpatients suffering from a severe major endogenous depression, diagnosed by Research Diagnostic Criteria and the Newcastle Rating scale, and to examine the effects of alprazolam and amitriptyline on two biological markers of depression, the dexamethasone suppression test and sleep EEG parameters. The 6-week study was double-blind with a random allocation of treatment. Patients were treated with flexible doses of 4-9 mg of alprazolam and 100-225 mg of amitriptyline. After 4 weeks of treatment the antidepressant effects of amitriptyline significantly exceeded those of alprazolam, as measured on the Hamilton Rating Scale for Depression. There was a high drop-out rate in the alprazolam group because of ineffectiveness of treatment. Alprazolam showed similar effects on sleep parameters as amitriptyline: lengthening of the REM latency and a tendency to shorten stages 3 and 4 and stage REM. These negative clinical results should be interpreted with caution, because of the severity of our selection criteria, and should not be extended to all depressive disorders.  相似文献   
83.
Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.  相似文献   
84.
Cortical malformations resulting from aberrant brain development can be associated with mental retardation, dyslexia, and intractable forms of epilepsy. Despite emerging interest in the pathology and etiology of cortical malformations, little is known about the phenotype of cells within these lesions. In utero exposure to the DNA methylating agent methylazoxymethanol acetate (MAM) during a critical stage in neurodevelopment results in animals with distinct clusters of displaced neurons in hippocampus, i.e. nodular heterotopia. Here we examined the molecular and electrophysiological properties of cells within hippocampal heterotopia using rats exposed to MAM during gestation. Molecular analysis revealed that heterotopic cells do not express mRNA markers normally found in hippocampal pyramidal cells or dentate granule cells (SCIP, Math-2, Prox-1, neuropilin-2). In contrast, Id-2 mRNA, normally abundant in Layer II-III supragranular neocortical neurons but not in CA1 pyramidal neurons, was prominently expressed in hippocampal heterotopia. Current-clamp analysis of the firing properties of heterotopic neurons revealed a striking similarity with supragranular cortical neurons. In particular, both cells were characterized by small hyperpolarizing 'sag' potentials, high input resistance values, slow spike-train afterhyperpolarizations, and the absence of a depolarizing afterpotential. Normotopic CA1 pyramidal neurons (e.g. pyramidal cells with normal lamination adjacent to a heterotopia) in the MAM brain exhibited molecular and electrophysiological properties that were nearly identical to those of age-matched CA1 pyramidal neurons from control rats.We conclude that neuronal heterotopiae in the hippocampus of MAM-exposed rats are comprised of neurons with a Layer II-III supragranular cortex phenotype. The MAM model, therefore, may serve as a useful tool in examination of the factors influencing aberrant brain development and epilepsy.  相似文献   
85.
Pigmented nodular cortical hyperplasia, a rare cause of Cushing’s syndrome, is characterized by resistance to inhibition with dexamethasone and normal sized adrenal glands with multiple, small pigmented nodules. The disorder may be a component of a syndrome inherited as an autosomal dominant pattern that includes intra- and extracardiac myxomas, lentiginous lesions, blue nevi, other functional endocrine tumors, and peripheral nerve tumors (Carney’s complex). We report a patient in whom bilateral myelolipomas were found, in addition to the usual features of this complex. A 29-yr-old man was admitted to the hospital for Cushing’s syndrome of probably more than 15 yr duration. Physical examination showed diffuse facial hyperchromatic macules, 0.2–0.5 cm, predominantly around the lips and on the palmar surfaces of the fingers. Results with dexamethasone suppression nocturnal testing (1 and 8 mg) were compatible with an adrenal adenoma. The computed tomography (CT) of the sella turcica was normal. Adrenal CT showed a tumor in the left gland with a double component: one solid and another suggestive of fat, consistent with an angiomyelolipoma. Following 5 wk treatment with ketoconazole, 800 mg per day po, serum cortisol decreased to 5.9 μg/dL, morning and evening, respectively. Bilateral adrenalectomy was performed. Pathologic examination revealed pigmented nodular cortical hypersplasia and a dominant myelolipoma in the left adrenal. A microscopic myelolipoma was identified in the right adrenal. An echocardiogram showed a mass on the posterior wall of the left ventricle which was a myxoma. Study of the patient's family disclosed two sisters with facial lentigines. Echocardiograms were performed on all available first degree relatives: all were normal. Nocturnal inhibition with dexamethasone revealed that one of the patient’s sisters with lentigines also had hypercortisolism. Myelolipoma has been reported in association to Cushing syndrome in humans and experimentally after pituitary extracts in animals. The relationship between this finding and the Carney’s complex remain elusive.  相似文献   
86.
The expression and cellular localization of angiotensin II (Ang II) and AT(1) receptor proteins were examined in the normal human prostate and benign prostatic hyperplasia (BPH) by immunohistochemistry. In the normal prostate, Ang II immunoreactivity was localized to the basal layer of the epithelium and AT(1) receptor immunostaining was found predominantly on stromal smooth muscle and also on vascular smooth muscle of prostatic blood vessels. Ang II immunoreactivity was markedly increased in hyperplastic acini in BPH compared with acini in the normal prostate (normal: 7.4+/-0.2%, n=5 vs. BPH: 22.7+/-1.9%, n=5, p<0.001). However, AT(1) receptor immunoreactivity was significantly decreased in BPH compared with the normal prostate [normal: 16.4+/-2.2%, n=4 vs. BPH: 9.4+/-1.3%, n=5, p<0.05 (p=0.025)]. The present study demonstrates the presence of Ang II peptide in the basal layer of the epithelium and AT(1) receptors on stromal smooth muscle, suggesting that Ang II may mediate paracrine functions on cellular growth and smooth muscle tone in the human prostate. Furthermore, AT(1) receptor down-regulation in BPH may be due to receptor hyperstimulation by increased local levels of Ang II in BPH. These data extend previous findings in support of the novel concept that overactivity of the renin-angiotensin system (RAS) may be involved in the pathophysiology of BPH.  相似文献   
87.
In order to examine the meal pattern characteristics associated with bulimia nervosa the meal patterns of 19 untreated bulimia nervosa, 12 recovered bulimics, and 21 normal controls spontaneously eating in their natural environments were compared. Subjects reported in a diary everything they either ate or drank for seven consecutive days. Meal pattern correlations included comparisons of the groups in regard to meal size (and binge size), meal frequency, premeal and postmeal intervals, deprivation ratios, satiety ratios, stomach contents, and composition of meals and binges. Results indicated that, although total reported intake was normal, only 33% of the total calories consumed by the untreated bulimia nervosa subjects were not followed immediately by purging. Both purged and unpurged binges were twice as large as their meal sizes which did not differ from normal. It is hypothesized that the caloric restriction of the untreated bulimics is binge/purge specific, and is used by them as a form of weight control. The recovered group showed a lack of responsivity to the signals that influence meal size and intermeal intervals in normals including impaired social facilitation of eating. They also had larger meal sizes, and greater frequency of meals. It is theorized that recovered bulimics employ other, as yet unspecified, means of food intake restriction resulting in an abnormal feeding pattern.  相似文献   
88.
Inhibitory neurotransmission in the brain is largely mediated by GABA(A) receptors. Potentiation of GABA receptor activation through an allosteric benzodiazepine (BZ) site produces the sedative, anxiolytic, muscle relaxant, anticonvulsant and cognition-impairing effects of clinically used BZs such as diazepam. We created genetically modified mice (alpha1 H101R) with a diazepam-insensitive alpha1 subtype and a selective BZ site ligand, L-838,417, to explore GABA(A) receptor subtypes mediating specific physiological effects. These two complimentary approaches revealed that the alpha1 subtype mediated the sedative, but not the anxiolytic effects of benzodiazepines. This finding suggests ways to improve anxiolytics and to develop drugs for other neurological disorders based on their specificity for GABA(A) receptor subtypes in distinct neuronal circuits.  相似文献   
89.
During development and injury, pulmonary neuroendocrine (NE) cells may transiently express Clara cell 10 kD protein (CC10), a major product of the nonciliated progenitor cells for normal and neoplastic airway epithelia suggesting a close relationship between the cells. To assess the role of CC10 during NE differentiation, we studied CC10-deficient mouse lungs by immunohistochemistry and digital imaging. The knockout model revealed a lack of the disrupted gene product in the lung. Because NE cells, which occur as solitary cells or in neuroepithelial bodies (NEBS), comprise less than 1% of airway epithelia, we counted foci positive for each of the three NE markers--synaptophysin, calcitonin gene-related peptide (CGRP), and protein gene product (PGP) 9.5--and developed a method to analyze numerous airways in serial sections. Digitized images of slides were segmented with Photoshop imaging software. The length of airway epithelium and total section areas were then measured using MetaMorph image analysis software. A comparable range of NE foci was observed regardless of CC10 expression patterns with all three markers, suggesting that CC10 is not critical for NE ontogenesis. However, discrimination according to size revealed that wild-type lungs harbored 30% to 40% greater synaptophysin- and CGRP-containing NEBs relative to CC10 deficient lungs. We posit that an attenuation of pulmonary NE differentiation afflicts the CC10-deficient state. Our imaging application greatly facilitates the acquisition and analysis of complex structures such as the lung and promises to be a widely applicable technique for assessments of tissue sections.  相似文献   
90.
The sequence is presented of RNA-5 of Echinochloa hoja blanca tenuivirus, a second tenuivirus associated with rice cultivation in Latin America (after rice hoja blanca virus). The RNA is 1334 nucleotides long and contains in the complementary sense RNA a single long open reading frame. The deduced amino acid sequence of this open reading frame shows that it encodes a highly basic and hydrophilic 44 kD protein (pc5) with about 50% similarity to the pc5 protein of maize stripe virus (MStV). This and other features of the RNA are discussed.The GenBank accession number of the sequence reported in this paper is L47430.  相似文献   
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