123rc/medical_text huggingface dataset:
Immediate regional endocardial surface expansion following coronary occlusion in the canine left ventricle: disproportionate effects of anterior versus inferior ischemia. The exact time of onset of functional expansion after acute myocardial infarction/ischemia remains unclear in spite of its potential link to chronic pathologic infarct expansion and its potential implications for therapy. To examine this early change in ventricular morphology, 14 open-chest dogs were studied with two-dimensional echocardiography before and after occlusion (10 minutes) of the left anterior descending coronary artery (LAD, n = 7) or circumflex artery (CIRC, n = 7). The endocardial surface area (ESA) and the area of abnormal wall motion (AWM) were reconstructed from the echocardiographic data using a previously reported technique for quantitatively mapping the ESA and extent of AWM. For the total group (N = 14), the mean ESA before occlusion was 48.9 +/- 9.8 cm2, increasing to 65.7 +/- 18.9 cm2 at 10 minutes occlusion (p less than 0.001). For the LAD subgroup, the mean ESA before occlusion was 50.7 +/- 9.3 cm2, increasing to 79.1 +/- 14.1 cm2 at 10 minutes following occlusion (p less than 0.001). For the CIRC subgroup, the mean ESA before occlusion was 47.1 +/- 10.8 cm2, increasing to 52.3 +/- 12.6 cm2 at 10 minutes after occlusion (p less than 0.001). The ESA increase for the LAD subgroup was significantly larger than that of the CIRC subgroup (LAD range 14.5 to 49.9 cm2 versus CIRC range 1.5 to 9 cm2, p less than 0.0001). Coronary occlusion resulted in similarly sized regions of AWM for both subgroups (LAD, 31.3 +/- 12.2 cm2 versus CIRC, 25.9 +/- 10.3 cm2, p = n.s.). For the LAD group, the largest increase in endocardial circumference occurred within the zone of AWM at the apex (39.9 +/- 12%). The endocardial surface area therefore expands immediately after coronary occlusion and the magnitude of this process is primarily related to the site (anteroapical) rather than to the extent of AWM.
Reflections on the U.S. Preventive Services Task Force recommendations for screening for hypertension and hypercholesterolemia. The U.S. Preventive Services Task Force recommendations for screening for hypertension and high blood cholesterol are generally consistent with preexisting national guidelines promulgated by the Joint National Committee for Detection, Evaluation, and Treatment of High Blood Pressure and the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Cholesterol in Adults. While a welcome addition to the armamentarium of the clinician, the Task Force recommendations represent only a partial solution to our current epidemic of blood-pressure- and cholesterol-related cardiovascular disease. A meaningful reduction in society's burden of cardiovascular disease can be achieved only by complementing the Task Force recommendations with community-based mass treatment strategies aimed at shifting the distribution of blood pressure and cholesterol toward a biologically more normal pattern.
Mucosal injury and gamma-irradiation produce persistent gastric ulcers in the rabbit. Evaluation of antiulcer drug binding to experimental ulcer sites. A method producing persistent gastric ulcers in the rhesus monkey by combined mucosal injury and gamma-irradiation was modified and evaluated in the rabbit. gamma-Irradiation (800-1000 cGy) immediately after removal of 2-mm-diameter sections of antral mucosa resulted in ulcer craters 5-7 days later. Ulcer sites were characterized by loss of the mucosa, muscularis mucosa, and much of the submucosa. The exposed submucosa was coated with fibrin and necrotic debris infiltrated with heterophils, the rabbit equivalent of neutrophils. These ulcers strongly resemble human chronic gastric ulcers. Binding of Carafate (sucralfate; Marion Laboratories, Inc., Kansas City, MO) and Maalox (magnesia-alumina oral suspension; Wm. H. Rorer, Inc., Ft. Washington, PA) to ulcer and nearby nonulcer sites in the antrum was assessed 1 hour after drug dosing. Drug binding was determined by aluminum quantitation of stomach wall punch biopsies at necropsy. Both drugs significantly increased aluminum bound to the stomach wall compared with vehicle treatment. Significantly more antiulcer drug was bound to ulcer sites than to nearby nonulcer sites only after sucralfate administration. This model of persistent gastric ulcer should be useful to further study gastric ulcer pathogenesis and treatment.
High-dose epinephrine improves outcome from pediatric cardiac arrest. STUDY OBJECTIVE: Animal studies suggest that the standard dose of epinephrine (SDE) for treatment of cardiac arrest in human beings may be too low. We compared the outcome after SDE with that after high-dose epinephrine (HDE) in children with refractory cardiac arrest. DESIGN: Prospective intervention versus historic control groups. TYPE OF PARTICIPANTS: Two similar groups of 20 consecutive patients each (median ages, 2.5 and 3 years) with witnessed cardiac arrest who remained in arrest after at least two SDEs (0.01 mg/kg). INTERVENTIONS: Treatment with an additional SDE versus HDE (0.2 mg/kg). MEASUREMENTS AND MAIN RESULTS: The rates of return of spontaneous circulation and long-term survival were compared. Fourteen of the HDE group (70%) had return of spontaneous circulation, whereas none of the SDE group did (P less than .001). Eight children survived to discharge after HDE, and three were neurologically intact at follow-up. No significant toxicity from HDE was observed. CONCLUSION: HDE provided a higher return of spontaneous circulation rate and a better long-term outcome than SDE in our series of pediatric cardiac arrest. HDE may warrant incorporation into standard resuscitation protocols at an early enough point to prevent irreversible brain injury.
Carotid endarterectomy for elderly patients: predicting complications OBJECTIVE: To determine whether the complication or death rate from carotid endarterectomy can be predicted from hospital and physician structural variables, such as the hospital's teaching status or the number of endarterectomies done by the surgeon per year. DESIGN: Survey of medical records. After controlling for the severity of the patient's condition on the basis of data in the medical record at the time of the endarterectomy, regression analyses were used to predict the postoperative stroke, heart attack, and 30-day death rate as a function of patient, physician, and hospital characteristics. SETTING: Three geographic areas (states or large parts of states; average population, 3 million) in the United States. PATIENTS: Random sample of 1302 patients 65 years of age or older having carotid endarterectomy in 1981. INTERVENTION: Carotid endarterectomy. MEASUREMENTS AND MAIN RESULTS: Of 1302 patients, 11.3% had a postoperative stroke or heart attack or died within 30 days of the operation. Patient age, race, income, and gender; physician volume, board certification status, and age; and hospital size, for-profit status, ownership, and teaching status were not significantly related to the postoperative complication or death rate. If the surgeon was a graduate of a foreign, but not a Western European or Canadian, medical school, however, the average complication or death rate rose from 10.4% to 19.6% (P less than 0.05). CONCLUSIONS: The effectiveness of carotid endarterectomy depends heavily on its complication rate. Because complications after surgery cannot, in general, be predicted from structural variables, referring physicians cannot rely solely on the surgeon's experience and qualifications when recommending a carotid endarterectomy. The surgeon's and the hospital's actual postoperative complication and death rate should be considered.
Spontaneous pneumoperitoneum. A surgical dilemma. Pneumoperitoneum is usually the result of hollow viscus perforation with associated peritonitis. Nonsurgical spontaneous pneumoperitoneum incidental to intrathoracic, intra-abdominal, gynecologic, iatrogenic, and other miscellaneous causes not associated with perforated viscus have been documented in the literature. Seven cases of spontaneous pneumoperitoneum admitted over 3-year period to Grady Memorial Hospital, Atlanta, Georgia are reported. Six patients with pneumoperitoneum underwent exploratory laparotomy when clinical examination suggested an acute abdomen; no intra-abdominal pathology was documented in any of these patients. A seventh patient, on ventilatory support, was managed conservatively after performing a diagnostic peritoneal lavage that was negative. There were no cases of radiographically misdiagnosed pneumoperitoneum. Pneumoperitoneum, preceded by a reasonable incidental cause in a patient with a adequate abdominal examination, may warrant continued observation thus avoiding an unnecessary laparotomy.
Interpleural analgesia [published erratum appears in Heart Lung 1991 Jul;20(4):413] Postoperative pain relief is necessary not only for patient comfort, but also to facilitate ventilation and ambulation. The use of opioid analgesia, either intravenously, intramuscularly, or intraspinally, may be ineffective and can cause respiratory depression. The administration of local anesthetics into the pleural space is a technique of providing analgesia of rapid onset and long duration. This analgesia is accomplished without causing the respiratory depression or sedation associated with the use of opioids. Because innovative analgesic methods are often selected for critically ill patients presenting after surgery in the intensive care setting, critical care nurses may encounter patients receiving local anesthetics administered via interpleural catheter.
A study of HTLV-I and its associated risk factors in Trinidad and Tobago. Seroprevalence of human T-lymphotropic virus type 1 (HTLV-I) among a sample of persons selected from a government register of businesses in Trinidad was 3.2% in 1,025 persons of African descent compared to 0.2% among 487 persons of Asian descent and 0% among 46 persons of European-descent. In Tobago, from a coastal village, among persons of African ancestry ascertained as part of a cardiovascular survey, the rate was 11.4%, which was significantly higher when corrected for age and race than the rate in Trinidad. The seroprevalence rate of antibodies to hepatitis A and B was also significantly elevated in Tobago compared to Trinidad. HTLV-I seroprevalence rates were higher in females than males while hepatitis A and B rates were not significantly different in the two sexes. For males, age was a significant determinant of HTLV-I seropositivity, while for females, age, markers of poor sanitation, and hepatitis B were each independently linked to HTLV-I seropositivity. The frequent occurrence of multiple infectious exposures in persons of lower socioeconomic circumstances in this tropical environment may result in immune activation that heightens susceptibility to HTLV-I infection.
Focal myositis. A new cause for the pediatric neck mass. Focal myositis is an inflammatory pseudotumor of skeletal muscle that may involve the head and neck. It can closely mimic either a neoplastic or infectious process. We present the case of a 7-year-old boy with a 2-week history of a painful, unilateral neck swelling, fever, and torticollis. He failed to respond to antibiotic therapy and required an open neck exploration. An incisional biopsy of the indurated, inflammatory tissue adherent to his sternocleidomastoid muscle showed focal myositis. Focal myositis is an unusual, but important possibility in the differential diagnosis of any neck mass and especially one in a child. Although its cause is unknown, it is a self-limited disease and neither excisional biopsy nor radical resection is justified.
Abscess of the iliopsoas muscle diagnosed by magnetic resonance imaging and ultrasonography. We have reported a case of abscess of the iliopsoas muscle, in which a limp and hip pain pointed toward pathology of the hip. The diagnosis in such cases may be difficult unless there is close attention to the clinical history and a good physical examination is obtained. One ultrasonographic examination of the hip in such a patient, subtle differences between the iliopsoas muscles should alert the radiologist to examine the psoas muscle. Ultrasonography is instrumental in demonstrating the solid or cystic nature of the iliopsoas mass, while MRI depicts the extent and proximity of adjacent organs. Once an iliopsoas abscess is diagnosed, treatment includes parenteral antibiotics and drainage.
Coinheritance of two mild defects in low density lipoprotein receptor function produces severe hypercholesterolemia. A family is described in which the probands, twin girls, had severe hypercholesterolemia suggestive of familial hypercholesterolemia (FH). The mother of the twins had normal plasma cholesterol levels, and the father had only moderate hypercholesterolemia. Moreover, low density lipoprotein (LDL) binding studies in cultured fibroblasts and isolated lymphocytes in the parents failed to reveal significantly reduced LDL receptor activity that is typical of FH heterozygotes. Turnover studies of LDL in the parents, however, revealed low fractional clearance rates (FCRs) for LDL. In cultured fibroblasts and isolated lymphocytes from the twin probands, binding of normal LDL was half normal or less. LDL turnover studies in the twins revealed a marked reduction in FCRs for LDL. When the twins were treated with lovastatin, however, FCRs for LDL increased significantly, suggesting enhancement of LDL receptor activity. This finding along with LDL binding studies in the cultured cells infer that the twins did not have homozygous FH. In addition, all family members tested negative for familial defective apolipoprotein-B-100, and LDL isolated from the mother and twins showed normal binding to normal fibroblasts. The overall data suggest that the severe hypercholesterolemia in the offspring was due to inheritance of mild to moderate defects of LDL receptor function from both parents. Although the latter defects could not be detected with certainty by in vitro tests in each parent, they were evident from LDL turnover tests. Coinheritance of these defects apparently produced severe hypercholesterolemia in the offspring.
Muscle maximal O2 uptake at constant O2 delivery with and without CO in the blood. In the present study we investigated the effects of carboxyhemoglobinemia (HbCO) on muscle maximal O2 uptake (VO2max) during hypoxia. O2 uptake (VO2) was measured in isolated in situ canine gastrocnemius (n = 12) working maximally (isometric twitch contractions at 5 Hz for 3 min). The muscles were pump perfused at identical blood flow, arterial PO2 (PaO2) and total hemoglobin concentration [( Hb]) with blood containing either 1% (control) or 30% HbCO. In both conditions PaO2 was set at 30 Torr, which produced the same arterial O2 contents, and muscle blood flow was set at 120 ml.100 g-1.min-1, so that O2 delivery in both conditions was the same. To minimize CO diffusion into the tissues, perfusion with HbCO-containing blood was limited to the time of the contraction period. VO2max was 8.8 +/- 0.6 (SE) ml.min-1.100 g-1 (n = 12) with hypoxemia alone and was reduced by 26% to 6.5 +/- 0.4 ml.min-1.100 g-1 when HbCO was present (n = 12; P less than 0.01). In both cases, mean muscle effluent venous PO2 (PVO2) was the same (16 +/- 1 Torr). Because PaO2 and PVO2 were the same for both conditions, the mean capillary PO2 (estimate of mean O2 driving pressure) was probably not much different for the two conditions, even though the O2 dissociation curve was shifted to the left by HbCO. Consequently the blood-to-mitochondria O2 diffusive conductance was likely reduced by HbCO.
Neuropsychological assessment of monozygotic twins discordant for schizophrenia. A comparison of monozygotic twins discordant for schizophrenia controls for genetic variance and reduces variance due to environmental circumstances, thus serving to highlight differences due to phenotypic-related variables. In this study, we assessed 16 such twin pairs on a wide range of neuropsychological tests. The affected twins tended to perform worse than their unaffected counterparts on most of the tests. Deficits were especially severe on tests of vigilance, memory, and concept formation, suggesting that dysfunction is greatest in the frontotemporal cortex. While manifest symptoms were not highly associated with neuropsychological scores, global level of functioning was. To address the issue of genetic liability, we also compared the sample of discordant unaffected twins with a sample of seven pairs of normal monozygotic twins. No significant differences between the groups were found for any neuropsychological test. In fact, the results suggest that neuropsychological dysfunction is a consistent feature of schizophrenia and that it is related primarily to the clinical disease process and not to genetic or nonspecific environmental factors.
Interstitial irradiation and hyperthermia for the treatment of recurrent malignant brain tumors. Between June 1987 and June 1989, 29 recurrent malignant gliomas or recurrent solitary brain metastases in 28 patients were treated in a Phase I study of interstitial irradiation and hyperthermia. Patient age ranged from 18 to 65 years, and the Karnofsky Performance Status scores ranged from 40 to 90%. There were 13 glioblastomas, 10 anaplastic astrocytomas, 3 melanomas, and 3 adenocarcinomas. Catheters were implanted stereotactically after computed tomography-based preplanning. Hyperthermia was administered before and after brachytherapy, using one to six 2450- or 915-MHz helical coil microwave antennas and one to three multisensor fiberoptic thermometry probes. The goal was to heat as much of the tumor as possible to 42.5 degrees C for 30 minutes. Within 30 minutes after the first hyperthermia treatment, implant catheters were afterloaded with high-activity iodine-125 seeds delivering tumor doses of 32.6 to 61.0 Gy. Most patients had no sensation of heating. Complications included seizures in 5 patients, reversible neurological changes in 9 patients, a scalp burn in 1, and infections in 3. Of 28 evaluable 2-month follow-up scans, 11 showed definite improvement in the radiological appearance of the tumor, 4 were slightly improved, 7 were stable, and 6 showed tumor progression. Ten patients underwent reoperation for persistent tumor and/or necrosis. Eleven of 28 patients are alive 40 to 97 weeks after treatment. Thirteen patients died of a brain tumor, 2 died of extracranial melanoma metastases, 1 died of new brain melanoma metastases, and 1 died of a pulmonary embolus. The median survival was 55 weeks overall. Median survival has not yet been reached for the anaplastic astrocytoma subgroup. We conclude that interstitial brain hyperthermia using helical coil microwave antennas is technically feasible. The level of toxicity is acceptable, and the computed tomographic response rate is encouraging.
Obesity-related hypertension: evaluation of the separate effects of energy restriction and weight reduction on hemodynamic and neuroendocrine status. PURPOSE: Although weight reduction generally lowers blood pressure, it is unclear whether the response is due to concurrent dietary changes or to reduced body mass itself. In this study, the independent effects of energy restriction and weight reduction were examined prospectively in 24 obese, hypertensive, normoglycemic women whose dietary intake was tightly controlled. SUBJECTS AND METHODS: Sodium, potassium, and calcium intake, the polyunsaturated/saturated fat ratio, and the proportional composition of carbohydrate, fat, and protein were constant throughout the 5-month protocol. Hemodynamic and neuroendocrine status was evaluated in four 10-day hospital phases: two prior to weight loss (energy balance and then 800-kcal intake), and two after an average loss of 13 kg to normal body weight (800 kcal and then return to energy balance). RESULTS: Fasting serum insulin, triiodothyronine:reverse triiodothyronine ratio, resting metabolic rate, and heart rate declined, and sodium and potassium balances were negative during energy restriction. Catecholamines, renin, aldosterone, plasma volume, cardiac output, and blood pressure showed no consistent response to changes in energy intake. By contrast, weight reduction independently lowered blood pressure, plasma volume, cardiac output, and plasma renin activity. Body fat pattern remained unchanged. CONCLUSION: These results demonstrate that weight loss has a blood pressure-lowering effect that is distinct from energy restriction and that is related to changes in blood volume and cardiac output.
Impaired sympathetic nerve function in the inflamed rat intestine. The effect of intestinal inflammation on norepinephrine release from the myenteric plexus in the Trichinella spiralis-infected rat was assessed. Longitudinal muscle-myenteric plexus preparations were preincubated with [3H]norepinephrine and release was evoked by electrical field stimulation and KCl administration. Preincubation of preparations with desipramine or pretreatment of rats with 6-hydroxydopamine significantly suppressed the uptake and evoked release of [3H]norepinephrine; electrical field stimulation but not KCl-evoked release of [3H] norepinephrine was sensitive to tetrodotoxin. These results confirm the presence of functioning sympathetic nerves in the preparations. T. spiralis infection was associated with significant suppression of both electrical field stimulation and KCl-evoked release of [3H]norepinephrine on the sixth day postinfection, and the suppression persisted 100 days postinfection. No suppression of [3H]norepinephrine release was seen in the worm-free and noninflamed ileum of infected rats. Suppression of [3H]norepinephrine release from the jejunum of infected rats was attenuated by treatment with betamethasone (3.0 mg/kg SC daily). These results are consistent with the hypothesis that intestinal inflammation suppresses the release of norepinephrine from the myenteric plexus in the Trichinella-infected rat.
A clarification on endodontic flare-ups [comment] In an article on endodontic flare-ups by Robert J. Matusow, our research and publications are discussed. Since we found what we consider to be distortions and misinterpretations of our work, it was decided to clarify the apparent discrepancies found in Matusow's article.
Alcohol and pyruvate cardioplegia. Twenty-four-hour in situ preservation of hamster hearts. Isolated hamster hearts were first perfused with a normal Krebs-Henseleit medium to demonstrate comparable viability of hearts before perfusing and storing them for 24 hours in one of three solutions. The three solutions were a physiologic saline with pyruvate as the substrate and 4% alcohol to arrest the heart (group 1), a standard cardioplegic solution (group 2), and an alcohol-free physiologic saline with pyruvate as the substrate (group 3). Recovery in terms of rate/pressure product and oxygen consumption after 30 minutes of reperfusion was 81% and 93%, respectively, for group 1, 13% and 32% for group 2, and 70% and 72% for group 3. Percent of physiologic recovery was not related to recovery of adenosine triphosphate. The adenosine triphosphate level returned to approximately 40% control level in all three groups, and in all three groups inorganic phosphate remained approximately 320% over control level after 30 minutes of reperfusion. Phosphocreatine level significantly higher in groups 1 and 3 than in group 2, as a result of improved oxygen consumption. Intracellular pH, determined by phosphorous 31 nuclear magnetic resonance spectroscopy, was physiologic in groups 1 and 3 but alkaline in group 2. This alkalinity may have been caused by leaky membranes. Pyruvate helped preserve mitochondrial function during depressed oxygen delivery, such as was seen during the 24-hour storage period. Four percent alcohol arrested the heart; combined with pyruvate plus alcohol solution were better than a standard cardioplegic solution for maintaining functional capability.