123rc/medical_text huggingface dataset:
Dietary calcium, vascular reactivity, and genetic hypertension in the Lyon rat strain. In order to examine the relationship existing between dietary calcium and the development of hypertension, we developed a long-term study in the Lyon hypertensive rat strain (LH) and two control strains, the Lyon normotensive (LN) and low blood pressure rats (LL) given enriched (HCa, 2.5%), deprived (LCa, 0.03%) and normal (NCa, 0.6%) calcium diets. Evolution of body weight, systolic blood pressure (BP), plasma calcium and magnesium was monitored from 4 to 23 weeks of age. Total cardiovascular reactivity and contractile response of isolated aorta to norepinephrine were measured at 23 weeks of age. LH rats on HCa diet failed to develop hypertension (BP less than 150 mm Hg) whereas LH rats on LCa diet exhibited higher blood pressure levels than their controls fed the NCa diet. Moreover, in LN rats HCa diet slightly decreased BP whereas LCa had no effect. In the LL rats, on the contrary, only LCa diet slightly increased BP. In vivo responsiveness to NE was significantly higher in LH compared to LL and LN rats fed a NCa diet. HCa and LCa diets both induced a significant decrease in this response in LH rats. HCa diet increased the response in LN rats but decreased it in LL. In contrast, at the same age, the in vitro contractile response of isolated aorta to NE was significantly decreased in LH compared to LN and LL rats receiving NCa diet. Moreover in LH and LN rats on HCa diet the contractile response was markedly increased but no significant difference was observed with LCa diet.
Landau-Kleffner syndrome: a pharmacologic study of five cases. Five children with Landau-Kleffner syndrome (epilepsy, acquired aphasia, and continuous spike-wave discharges during sleep), were treated with antiepileptic drugs (AEDs), sleep-modifying drugs, and corticosteroids. The pharmacologic profiles differed from those observed in focal epilepsies, resembling instead those of certain generalized epilepsies, such as West or Lennox-Gastaut syndromes. Phenobarbital (PB), carbamazepine (CBZ), and phenytoin (PHT) were ineffective or worsened the EEG and neuropsychological symptoms, whereas valproate (VPA), ethosuximide (ESM), and benzodiazepines were partially or transiently efficacious. Dextroamphetamine produced a dramatic but transient improvement in waking and sleep EEG in one of two children; aphasia did not change. Corticosteroid treatment resulted in improved speech, suppression of seizures, and normalization of the EEG in three of three children. Our own experience and data from the literature suggest that corticosteroids should be given in high doses as soon as the diagnosis is firmly established and should be continued in maintenance dose for several months or years to avoid escape. Early diagnosis, before mutism or global deterioration develops, appears to be essential for effective therapy with minimal neuropsychological sequelae.
Endometrial ablation for the treatment of menorrhagia: a comparison of patients with normal, enlarged, and fibroid uteri. One hundred sixty-one patients underwent endometrial ablation with the Nd:YAG laser for the treatment of refractory menorrhagia. Patients were divided into one of three groups: those with a normal-sized uterus; those with an enlarged uterus (greater than 10 cm); and those with uterine fibroids, which had been documented clinically, ultrasonographically, or by a combination of hysteroscopy and laparoscopy or by one or the other. All patients were considered candidates for hysterectomy. Both preoperatively and postoperatively, patients monitored their menstrual cycles and evaluated their flow according to predetermined categories of amenorrhea, light flow, normal flow, heavy flow, and severe flow. After treatment, 68% of patients with normal-sized uterus and 91% of patients with an enlarged uterus (greater than 10 cm) and 88% of patients with uterine fibroids became amenorrheic or had light flow. None of the patients in this last group have had to undergo hysterectomy. This study indicates that the patient with an enlarged or fibroid uterus may not have contraindications for endometrial ablation. Endometrial ablation may be effective in at least temporarily controlling bleeding in those patients with enlarged or myomatous uterus.
The normal mediastinum in blunt traumatic rupture of the thoracic aorta and brachiocephalic arteries. In a review of 52 articles, published between 1953 and 1989, 656 patients with blunt traumatic rupture of the thoracic aorta or brachiocephalic arteries were identified. Of these, 608 (92.7%) had an abnormal mediastinum on initial chest radiographs obtained in the emergency department, thus allowing early detection of the vascular injury. Unfortunately, 48 (7.3%) of these patients had a normal mediastinum on their initial chest radiographs. This appears to occur when the traumatic pseudoaneurysm is not accompanied by associated mediastinal hemorrhage or hematoma formation, and the pseudoaneurysm is either small or is situated in such a way that it does not alter the mediastinal contour. The use of accessory clinical and radiographic signs to indicate the need for aortography has been shown to be of very low yield, but would have allowed the early detection of an additional 5.6% of the reported cases. Performing aortography solely on the basis of a history of major decelerating blunt trauma to the thorax remains the only way, in the acute emergency department setting, to detect the 1.7% of patients with aortic or brachiocephalic arterial rupture who have no mediastinal abnormality or accessory clinical or radiographic signs of vascular injury. There is evidence from the literature, however, to suggest that the evaluation of serial chest radiographs obtained at close intervals for the first month following trauma for the development of mediastinal abnormality or large hemothorax is an acceptable alternative to the routine performance of aortography in those blunt chest trauma victims with no clinical or radiographic suspicion of vascular injury.
Enhanced modulation of antibodies coating guinea pig leukemic cells in vitro and in vivo. The role of Fc gamma R expressing cells. We have investigated the antigenic modulation induced by a number of antibody fragments and derivatives directed against the idiotype of the surface Ig of the L2C guinea pig B lymphoblastic leukemia, and studied the effects upon such modulation of the simultaneous presence of cells expressing Fc gamma receptors (FcR). In vitro studies confirmed previous work showing that antibody bivalency is required to induce modulation in vitro in simple systems. However, in the presence of isolated Kupffer cells, Fc-containing univalent antibodies were found to induce significant antigenic modulation, and the modulation induced by intact IgG was also found to be more rapid and extensive. Fragments that did not contain Fc regions behaved similarly in the presence or absence of Kupffer cells. Further investigations demonstrated that all three classes of human FcR can mediate modulation enhancement, and suggest that the mechanism involves indirect cross-linking of cell surface Ag via the antibody and effector cell FcR. In vivo studies showed that univalent antibody derivatives containing Fc regions did induce antigenic modulation, but that this was significantly reduced in comparison with bivalent antibodies, confirming their potential advantage for immunotherapy.
Use of quinapril in the elderly patient. Quinapril hydrochloride is a nonsulfhydryl angiotensin converting enzyme (ACE) inhibitor that has been extensively tested and found effective when administered once-a-day to hypertensive patients of both sexes and all degrees of hypertension and cardiac compromise, including those with left ventricular hypertrophy, with and without congestive heart failure. Observations with earlier ACE inhibitors led to reports that this class of drugs was relatively ineffective in older hypertensive patients. To ascertain the role of quinapril (greater than or equal to 10 mg/day) in older patients, its blood pressure-lowering effects in 1,175 hypertensive patients less than or equal to 65 years of age were compared with those in 304 patients greater than 65 years of age. An excellent response was observed in patients greater than 65 years of age with mild to moderate hypertension (diastolic BP, 95 to 105 mm Hg) and moderate to severe hypertension (diastolic BP, 106 to 115 mm Hg). The reductions in blood pressure achieved with quinapril were at least comparable to those obtained in the younger hypertensives, and were numerically (but not statistically) greater in the mild to moderate group (-14 mm Hg v-12 mm Hg). In addition, the percentage of patients who experienced adverse experiences was lower in the greater than 65 group than in the less than or equal to 65 group (15% v 19%). The main adverse experiences reported included dizziness, headache, cough, fatigue, and hypotension. These findings indicate that quinapril is at least as safe and effective in older hypertensives as in younger patients.
Diagnostic imaging and surgical treatment of dumbbell tumors of the mediastinum. We describe the diagnostic procedures and surgical approaches employed in 5 patients with dumbbell tumors of the mediastinum. Magnetic resonance imaging accurately described the existence and longitudinal extension of the intraspinal component of the tumor and assisted in choosing the appropriate surgical approach. Both the intrathoracic and intraspinal components of the tumor were resected at one time by a thoracic and neurosurgical team. We employed the Grillo technique three times and a separate laminectomy and thoracotomy approach. Magnetic resonance imaging proved the most useful diagnostic technique for suspected dumbbell mediastinal tumors. In our experience, the extended thoracotomy proposed by Grillo and co-workers worked well for small tumors involving only one foramen in which the intraspinal extension was limited to 2 to 3 cm, and when no more than two laminectomies were required. On the other hand, thoracotomy and a longitudinal paravertebral incision are preferable for larger tumors (more than 4 cm) involving more than one foramen in which the intraspinal extension exceeds 2 to 3 cm, for tumors requiring multiple laminectomy, and when bony infiltration is present.
Aortocaval and iliac arteriovenous fistulas: recognition and treatment. Despite the well characterized physiologic effects of aortocaval or iliac arteriovenous fistulas, patients with such uncommon lesions may manifest a diverse array of symptoms, and diagnosis is often delayed or overlooked. To examine clinical features that facilitate recognition and allow successful repair, a 30-year experience with 20 such fistulas was reviewed. Fourteen fistulas were caused by aneurysm erosion, four followed iatrogenic injury during lumbar disk surgery, and two developed from abdominal gunshot wounds. The interval from presumed occurrence to diagnosis ranged from 3 hours to 8 years. The diagnosis was not recognized before surgery in five (25%) patients. Back pain (70%) was the most common symptom. The presence of a typical abdominal bruit (80%) was the most reliable physical finding, but its significance was occasionally overlooked or misinterpreted. Congestive heart failure was prominent in only seven (35%) patients. Severe lower extremity edema and mottling was the primary manifestation in eight cases, often causing initial confusion with venous thrombosis. Hematuria (5 patients) and oliguric renal failure (4 patients), both fully reversible after fistula repair, also caused diagnostic uncertainty. The mean preoperative cardiac output was 12.2 L/min, falling to 5.4 L/min with fistula repair. Mean blood loss was 5960 ml, supporting use of intraoperative autotransfusion. Two operative deaths (10%) occurred, both in patients not correctly diagnosed before surgery. Despite varied modes of presentation, prompt recognition and use of appropriate operative techniques should achieve successful repair.
Health effects of radon exposure. Report of the Council on Scientific Affairs, American Medical Association. The consensus of scientists is that exposure to radon is hazardous, but disagreement exists about the effects of lower radon concentrations. Studies of underground miners have indicated that the risk of lung cancer increases in proportion to the intensity and duration of exposure to radon, and a recent authoritative report (BEIR IV) has concluded that estimates based on those studies are appropriate for estimating risks for occupants of homes. The BEIR IV report concluded that smoking cigarettes increases the risk of lung cancer associated with radon. Average radon levels in US homes range from 0.055 to 0.148 Bq/L (1.5 to 4 pCi/L), depending on the circumstances of measurement. Few studies have investigated health outcomes in occupants of homes with high radon levels. In advising patients about reducing the risks associated with radon, physicians should consider the costs, as well as the benefits, of remedial actions, and they should emphasize that, by far, the best way to avoid lung cancer is to stop smoking.
Traumatic popliteal artery pseudoaneurysms: case report and review of the literature. Traumatic pseudoaneurysms of the popliteal artery are an uncommon late complication of arterial injury. Although reviewed extensively in wartime, they occur less frequently in civilian trauma and have accordingly been less frequently studied. A case report of a traumatic popliteal artery pseudoaneurysm and review of the literature are presented.
Genetic determination of cytomegalovirus-induced and age-related cardiopathy in inbred mice. Characterization of infiltrating cells. Carditis developed 7 days after the administration of murine cytomegalovirus to neonatal, young adult or aged mice of varying sensitivity to lethal infection with this virus. The inflammation persisted for up to 80 days, but infected myocardial cells were rare and were not seen after day 10. The inflammatory cells comprised macrophages (up to 30%) and T cells (up to 80%), with a high ratio of Lyt2+ to L3T4+ cells throughout. Although the H-2 genotype affects murine cytomegalovirus replication at the level of individual cells, and hence resistance to lethal infection, it did not determine resistance to cardiopathy per se. However BALB/c, BALB.B, and BALB.K mice developed persistent myocarditis regardless of age at infection, and age-related cardiopathy was frequent and severe in infected and uninfected mice. B10 and B10.BR mice also developed myocarditis after neonatal infection, but inflammation resolved rapidly after adult infection and age-related cardiopathy was correspondingly mild. C3H mice exhibited minimal carditis after neonatal or adult infection. However neonatal infection appears to accelerate age-related cardiopathy, which is severe in retired breeders of this strain.
Intraoperative ultrasonic imaging of the ascending aorta in ischemic heart disease. In an attempt to locate any atherosclerotic lesion in the ascending aorta and to prevent embolization, intraoperative B-mode ultrasonography was performed in 100 patients with ischemic heart disease (31 women and 69 men). Ultrasonography was carried out with a 10-MHz probe placed directly on the ascending aorta. Ultrasonic imaging demonstrated an atherosclerotic lesion in the lower half of the aorta in 76 patients (76%), a lesion in the upper half of the aorta in 89 patients (89%), and a lesion at the orifice of the innominate artery in 99 patients (99%). Prospective palpation identified an atherosclerotic lesion in 12 (25%) of 48 patients. Thoracic computed tomography in 79 patients showed calcification in the lower half of the aorta in 6 patients (7.6%) and in the upper half of the aorta in 11 (13.9%). Palpation and thoracic computed tomography underestimated the frequency of atherosclerotic lesions. Intraoperative ultrasonography accurately identified atherosclerotic disease. This technique allows the surgeon to modify cannulation, aortic clamping, and operative technique to reduce the risk of perioperative stroke due to embolization of atherosclerotic debris from the ascending aorta.
Power of oesophageal peristalsis can be controlled voluntarily. The hypothesis that oesophageal peristalsis can be modified voluntarily was explored. Six healthy male volunteers and eight female patients with angina like chest pain underwent oesophageal manometry. Each was asked to take a series of swallows, and to vary their size, in random order, by taking either a big gulp or a little swallow. None of the subjects experienced difficulty in doing so. In both groups the amplitude of oesophageal contractions were significantly greater after big gulps than little swallows (p less than 0.01) and this was true for wet (82.0 v 68.9 mmHg) and dry swallows (52.3 v 43.3 mmHg). For the patients' wet swallows the mean values were 73.0 and 56.0 mmHg. Thus, the amplitude of oesophageal peristalsis can be controlled voluntarily. This effect may account for some of the within subject variation in the amplitude of oesophageal contractions. During oesophageal manometry subjects should be encouraged to standardise the size of their swallows whenever possible. Patients with symptoms related to abnormal oesophageal peristalsis such as dysphagia, heartburn, and chest pain may benefit from biofeedback training.
Long-term effect of mexiletine on left ventricular function and relation to suppression of ventricular arrhythmia. The effects of oral mexiletine on left ventricular (LV) ejection fraction (EF) and ventricular arrhythmias--and a possible relation between these effects--were evaluated during 3 months of therapy in 29 patients with chronic ventricular premature complexes (VPCs) and a moderately reduced to normal LVEF by 24-hour Holter monitoring and by radionuclide ventriculography at rest and during maximum tolerable exercise testing. After an average titration period of 13 days, a mean daily mexiletine dose of 739 mg was maintained throughout the treatment. At the end of titration and after 3 months of treatment, patients with a baseline LVEF less than or equal to 40% (group 2) responded with a median reduction of the hourly VPC rate by 90 and 81%, respectively, compared with 79 and 72% in those with a baseline LVEF greater than 40% (group 1). Couplets and runs of ventricular tachycardia were almost completely suppressed in nearly all patients. A single patient had a proarrhythmic increase in VPCs during treatment. Compared with baseline, there were no significant changes in resting or exercise LVEF after 1 or 3 months of treatment in either of the 2 groups of patients. No correlation was found between treatment-induced changes in arrhythmia frequency and in resting EF. No symptoms of congestive heart failure developed. The study confirms that long-term use of mexiletine is efficacious and relatively free of cardiac depressant effects even in patients with diminished LV function.
Carcinoma of the vulva. Clinicopathologic factors involved in inguinal and pelvic lymph node metastasis. Eighty-five women with vulvar squamous cell carcinoma were subjected to radical vulvectomy with bilateral inguinal and femoral node dissection or to radical vulvectomy with bilateral inguinofemoral and deep pelvic node dissection. The association between lymph node status (metastatic or not) and several parameters was analyzed: tumor location, size and clinical stage; tumor thickness, histologic grade and mitotic index; blood vessel, lymphatic and perineural infiltration; and lymphocytic and plasma cell infiltrates. There were no metastases to the pelvic lymph nodes without previous inguinal lymph node involvement. Unilateral vulvar carcinomas did not have contralateral metastatic nodes when there was no ipsilateral nodal involvement. Lymphatic vessel infiltration showed a statistically significant correlation with inguinal node metastases (P less than .05). No correlation was found between lymph node metastasis and tumor size, clitoral invasion, tumor thickness, histologic grade, blood vessel and perineural infiltration, lymphocytic and plasma cell infiltrates, and mitotic index.
Continuing care for cancer pain relief with oral morphine solution. One-year experience in a regional cancer center. This report is a prospective study of 223 patients with intractable cancer pain who were offered continuing care during the year 1988 at the Pain Relief Unit, Kidwai Memorial Institute of Oncology, Bangalore, India, with a minimum follow-up of 4 months and a maximum follow-up of 16 months. A high percentage of pain relief was attained within a mean duration of 4 days, which on follow-up was maintained at a steady level in most patients (91.1%). Oral morphine could not be continued in three patients because of vomiting. The main side effects noticed were nausea and vomiting, itching, and constipation. At any time during the first 140 days, only 30% of patients had side effects and appropriate medication successfully managed these side effects. During the rest of the study period, the side effects were minimal. Oral morphine used with proper adjuncts offers the best pain palliation in most patients, with minimal side effects.
Aortobronchial fistula after an aortic operation. A 71-year-old man with a postoperative aortobronchial fistula was successfully treated. The fistula occurred between the left lower lobe and the descending thoracic aorta, to which a distal anastomosis of a temporary bypass graft had been placed during thoracic aortic aneurysmectomy 3 years before. For saving patients with this complication, early surgical treatment during episodes of intermittent hemoptysis is important. The use of an omentum pedicle flap for the isolation of the suture line is a important adjunct.
Myocardial metabolic and hemodynamic effects of a sustained intravenous infusion of nifedipine with and without metoprolol in patients with unstable angina. We tested the usefulness of a sustained intravenous infusion of nifedipine and a combination of nifedipine and metoprolol in the early management of 14 patients with unstable angina pectoris. After a 24-hour run-in period, nifedipine was titrated in a stepwise fashion (mean dose 27 +/- 7 micrograms/min). After nifedipine treatment coronary blood flow increased from 150 +/- 66 to 183 +/- 74 ml/min (p less than 0.05), whereas double product, myocardial oxygen consumption, and both arterial and coronary sinus (nor)epinephrine levels were unchanged. Myocardial lactate uptake increased from 3.4 +/- 26.1 to 31.3 +/- 26.6 mumol/min (p less than 0.005) and free fatty acid uptake from 7.2 +/- 22.1 to 34.5 +/- 33.7 mumol/min (p less than 0.05). A small nonsignificant improvement in amino acid metabolism was observed. Metoprolol was added in seven patients and led to a decrease in double product (-2.2 +/- 1.6 x 10(3); p less than 0.01) and myocardial oxygen consumption (-3.2 +/- 3.8 ml/min; p less than 0.05). The lactate uptake/oxygen uptake ratio increased by 18% after metoprolol (p = NS). The number of episodes of chest pain decreased from 2.4 +/- 1.1/24 hours to 0.1 +/- 0.2 in the nifedipine group and from 2.9 +/- 1.1/24 hours to 0.3 +/- 0.5 in the nifedipine plus metoprolol group (both p less than 0.01). We conclude that in the acute phase of unstable angina, intravenous nifedipine can be carefully titrated to improve coronary blood flow and oxidative metabolism. The addition of metoprolol is also associated with a reduction in myocardial oxygen demand. This treatment results in significant hemodynamic stability.