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R Poland

Publications and source records attributed to R Poland.

11 recordsLinked to original sources

Effect of venlafaxine on imipramine metabolism.

The present study was designed to determine the effect of venlafaxine on imipramine metabolism in an attempt to elucidate the potential for cytochrome P450 drug-drug interactions with venlafaxine. We examined the metabolism of a single 100-mg dose of imipramine before and after treatment with venlafaxine, 50 mg three times a day. Eight male subjects were phenotyped for CYP2D6 activity. Two subjects were poor metabolizers of dextromethophan, and data from the remaining six subjects (mean age=45.3+/-15) were analyzed. Venlafaxine increased imipramine C(max) and elevated AUC by 40%. Desipramine clearance and volume of distribution were reduced by 20% and 25%, respectively. These findings are consistent with a statistically significant, but clinically modest impact of venlafaxine on CYP2D6-metabolized substrates.

Adult↗

Antenatal phenobarbital therapy and neonatal outcome. I: Effect on intracranial hemorrhage.

OBJECTIVE: To evaluate the effect of antenatal phenobarbital (PB) therapy on neonatal intracranial hemorrhage (ICH) in preterm infants. DESIGN: Prospective, randomized, controlled trial. SETTING: Single institution study. SUBJECTS AND INTERVENTIONS: Women in preterm labor ( < 35 weeks' gestation) were assigned to control and treatment groups. The treatment group received 10 mg/kg (maximum, 1000 mg) PB intravenously, followed by 100 mg orally daily, until delivery. Neonates did not receive PB after birth. Head sonograms were performed on days 3, 7, and 14 and at discharge. Hemorrhage was classified as mild, moderate, or severe by a single reader. OUTCOME MEASURES: Incidence of neonatal ICH in all infants, infants weighing less than 1250 g, and infants of multiple gestations. RESULTS: The study population comprised 110 women, 60 in the control group and 50 in the PB group. Neonates in the control group (n = 74, including 10 pairs of twins and 2 sets of triplets) were comparable to those in the treatment group (n = 62, including 7 pairs of twins, 1 set of triplets, and 1 set of quadruplets) regarding birth weight, gestational age, and other clinical risk factors for ICH. There was a trend for the incidence of any grade of hemorrhage to be lower in the PB group (22% [14 of 62]) compared with the control group (35% [26 of 74]). Moderate and severe hemorrhages were significantly lower in the PB group (1.6% [1 of 62]) compared with the control group (9.4% [7 of 74]). Among infants weighing less than 1250 g, overall ICH was lower in the PB group (23% [6 of 26]) compared with the control group (51% [18 of 35]). Among multiple-gestation infants, overall ICH was 4.7% (1 of 21) in the PB group, compared with 31% (8 of 26) in the control group. CONCLUSIONS: Antenatal PB therapy results in a significant decrease in moderate and severe ICH in infants born at less than 35 weeks' gestation. Antenatal PB therapy also resulted in a decrease in the incidence of all grades of ICH in infants weighing less than 1250 g and infants born of multiple gestations.

Administration, Oral↗

Differential diagnosis and pathophysiology of Cushing's syndrome and primary affective disorder.

Most patients with major depression have increased 24-hour urinary free cortisol and cortisol nonsuppression after dexamethasone administration, which are cornerstones of a diagnosis of Cushing's syndrome. Similarly, Cushing's syndrome patients often suffer from major psychiatric syndromes, most often depression. These similarities between the two conditions sometimes make it difficult to differentiate them and have led some investigators to suggest they are two points on a spectrum of endocrinologic dysfunction. This article reviews the literature comparing Cushing's syndrome and primary affective disorder and presents two cases that illustrate just how closely these diseases may resemble one another.

Adrenocorticotropic Hormone↗

Vitamin A deficiency and pulmonary oxygen toxicity: morphometric studies in the murine lung.

Vitamin A and its precursor beta-carotene are naturally occurring antioxidants. The effects of diets deficient in beta-carotene and vitamin A on the alveolar-capillary membrane were studied in young adult BALB/C mice before and after exposure to 65% oxygen. One of three diets (standard complete, beta-carotene deficient, or beta-carotene and vitamin A deficient) was fed for a 6-wk period. Mice were then exposed to 65% oxygen for 0, 3, or 6 days, sacrificed, and their lungs examined by electron microscopy using the morphometric techniques of Weibel. The arithmetic and the harmonic mean thicknesses of the alveolar-capillary membrane and its components (epithelium, interstitium, and endothelium) were measured to assess the influences of diet and of duration of exposure to 65% oxygen. Analysis of variance and multiple comparisons of means (Student-Neuman-Keuls statistics) were applied. Diet alone did not significantly affect membrane thickness. However, duration of oxygen exposure increased the thicknesses of both the epithelium and interstitium in the group fed a diet deficient in both beta-carotene and vitamin A as compared to the other two groups although this was only significant for the epithelium. beta-Carotene deficiency alone did not affect the respiratory membrane either before or after oxygen exposure. These results suggest that vitamin A may be an important nutrient in the protection against pulmonary oxygen toxicity.

Animals↗

Thoracic spinal cord (T3-T4) transection in a breech-presenting, cesarean-section-delivered preterm infant.

Thoracic spinal cord transection below the origin of the brachial plexus is a rare event among breech-presenting infants delivered by cesarean section. A case of a thoracic (T3-T4) spinal cord injury with paravertebral hemorrhage mimicking catastrophic intracranial bleeding is presented to illustrate the value of careful application of traction or any longitudinal stretching forces during fetal head extraction.

Adult↗

Neonatal resuscitation.

The long-term outcome of infants subjected to perinatal asphyxia can be improved if they are recognized as high risk before birth and managed so as to reduce the period of hypoxemia to a minimum. Prompt and effective resuscitation of asphyxiated infants at the time of birth can contribute much to improving the long-term outcome of these infants.

Airway Obstruction↗

Familial T-cell lymphoblastic lymphoma: association with Von Recklinghausen neurofibromatosis and Gardner syndrome.

A family is described in which three of seven siblings developed a T-cell lymphoblastic lymphoma. Tumor cells formed rosettes with sheep erythrocytes, lacked surface Ig, and expressed human T- but not B-lymphocyte antigens. They lacked the enzyme terminal transferase suggesting a lymph node rather than thymic T-cell origin. Autopsy findings supported this conclusion. All three sibs, like their father, had numerous cafe'-au'lait spots indicative of Von Recklinghausen neurofibromatosis. One child had a subcutaneous fibroma, and another had multiple colonic polyps and exostoses characteristic of Gardner syndrome. Both are autosomal dominant conditions known to predispose to malignancies. The genetic factors responsible for these conditions may also predispose to the development of "post-thymic" T-cell lymphoblastic lymphoma.

Child↗

Brain damage, stress, and life span: an experimental study.

Mice received frontal pole transections or sham operations, and approximately half in each group experienced cold stress five times throughout their lives. On two occasions certain selected animals were subjected to cold + restraint stress. Neither the brain lesions nor the cold stress affected life span. The stressors, however, were effective in temporarily elevating serum corticosterone levels and, in the case of cold + restraint, producing gastric stress erosions. A significant partial correlation between stress and cause of death was found. This effect appeared to be due primarily to reticulum cell sarcomas metastasizing to the lung (pulmonary tumors) with much greater frequency among animals exposed to stress.

Animals↗