shukoor65/lab-rag-model huggingface dataset:
Thallium-201 scintigraphy after intravenous infusion of adenosine compared with exercise thallium testing in the diagnosis of coronary artery disease Adenosine is an endogenously produced compound that has significant effects as a coronary and systemic vasodilator. Previous studies suggest that intravenous infusion of adenosine, coupled with thallium-201 scintigraphy, may have specific value as a noninvasive means of evaluating coronary artery disease. The purpose of this study was to compare the diagnostic value of adenosine thallium testing with that of standard exercise thallium testing. One hundred subjects were studied with exercise thallium imaging and thallium imaging after adenosine infusion, including 47 with angiographically proved coronary artery disease and 53 control subjects. The overall sensitivity of the thallium procedures was 81% for the exercise study and 83% for the adenosine study (p = NS); the specificity was 74% for the exercise study and 75% for the adenosine study (p = NS). The diagnostic accuracy of the exercise study was 77% and that of the adenosine study was 79%. Ninety-four percent of subjects had an adverse effect due to the adenosine infusion; however, most of these effects were mild and well tolerated. All adverse effects abated within 30 to 45 s of the termination of the study, consistent with the very brief half-life of the agent. Thus, thallium-201 scintigraphy after intravenous infusion of adenosine has a diagnostic value similar to that of exercise thallium testing for evaluation of coronary artery disease. Adenosine thallium testing may be particularly useful in evaluating patients unable to perform treadmill exercise testing.
Retroperitoneal fibrosis. Retroperitoneal fibrosis is idiopathic in two thirds of cases and is found most commonly as an isolated fibrotic plaque centered over the lower lumbar spine and entrapping one or both ureters. It has been postulated that the fibrosis in the idiopathic cases results from a hypersensitivity reaction to antigens leaking into the retroperitoneum from atheromatous plaques in the aorta or common iliac arteries. In the remaining one third of cases, causes include ergot-derivative drugs, retroperitoneal hemorrhage or urine extravasation, and a desmoplastic response to a variety of tumors. In up to 15% of cases, associated fibrotic processes are found elsewhere in the body. Although the disease is imaged best with CT or MR, neither of these techniques can be used to differentiate benign from malignant plaques. Histologically, the disease is characterized in its early stages by inflammatory cells and edema in a loose collagen network. The mature plaque is composed of dense fibrous tissue with minimal cellular infiltration. This progression is important as it influences MR signal characteristics.
Influence of the plasma protein concentration on renal function. 1. The effect of the plasma protein concentration on renal function remains controversial. Most, but not all, experimental studies suggest that a reduced plasma protein concentration perfusing the kidney may reduce tubular sodium reabsorption. Hypoproteinaemic disease states are usually associated with sodium retention, which is not always volume-dependent. 2. We induced a 21% and 24% reduction in plasma total protein and plasma albumin, respectively, in unanaesthetized sheep by acute extracorporeal plasmapheresis. Arterial pressure did not change, and changes in circulatory volume were minimised by infusion of crystalloid to maintain pulmonary artery occlusion pressure, measured using a Swann-Ganz pulmonary artery catheter. 3. After plasmapheresis, there was no significant change in creatinine clearance, sodium excretion, plasma renin activity or urinary kallikrein excretion. 4. After plasmapheresis, there was no significant reduction in plasma osmolality, increase in urine osmolality and fall in free water clearance. 5. The results suggest that in the absence of detectable changes in circulating volume or arterial pressure, acute hypoproteinaemia is associated with significant changes in renal water handling, but has no direct effect on sodium excretion or on renal release of renin and kallikrein.
Effect of high-dose methylprednisolone and U74006F on eicosanoid synthesis after subarachnoid hemorrhage in rats. Free radicals and lipid peroxidation of membrane fatty acids are thought to play a role in the pathogenesis of arterial vasospasm and the physiopathologic patterns of neuronal damage after subarachnoid hemorrhage. We have evaluated the effects of treatment with either high-dose methylprednisolone every 8 hours or a single dose of U74006F on the temporal profile of ex vivo synthesis of four selected eicosanoids in brain slices after experimental induction of subarachnoid hemorrhage in rats. Prostaglandins D2 and E2, prostacyclin and leukotriene C4 levels were determined by radioimmunoassay after 1-hour incubation of the brain slices. The synthesis of prostaglandin D2 and 6-ketoprostaglandin F1 alpha at 48 hours after subarachnoid hemorrhage was significantly higher when compared to sham-operated animals (p = 0.01); prostaglandin E2 release was significantly enhanced at 6 hours after subarachnoid hemorrhage (p = 0.01). The release of the lipoxygenase metabolite was significantly enhanced at 1, 6, and 48 hours after subarachnoid hemorrhage induction. Both treatment regimens significantly reduced the ex vivo synthesis of prostaglandin D2, prostaglandin E2, and leukotriene C4 at 1, 6, and 48 hours after subarachnoid hemorrhage, whereas the effects on 6-ketoprostaglandin F1 alpha synthesis differed in the two treatment groups. U74006F enhanced the synthesis of prostacyclin metabolite in the early phase after subarachnoid hemorrhage, and high-dose methylprednisolone reduced the increasing synthesis at 48 hours. A strict comparison between the two treatments was not possible because of the different modalities of administration. However, these data suggest that the antioxidant effect of single-dose treatment with U74006F influenced the early and delayed effects on enzymatic lipid peroxidation, whereas the effects of methylprednisolone administration every 8 hours were more significant in the delayed phase.
Brain and ocular abnormalities in infants with in utero exposure to cocaine and other street drugs. We describe 10 infants with developmental delay and congenital cerebral anomalies who were found to have had in utero exposure to vasoactive drugs. Nine infants had ophthalmological abnormalities; these included strabismus, nystagmus, and/or hypoplastic optic discs. Six mothers used cocaine, one used cocaine and heroin, one used only heroin, one used amphetamine, and one used phenylpropanolamine. Each of these cerebral anomalies (agenesis of the corpus callosum, septo-optic dysplasia, schizencephaly, hydranencephaly, congenital hydrocephalus, porencephaly, and cerebral infarctions) can be attributed to insults at different stages of development. There appears to be a relationship between the time of prenatal drug exposure and the type of cerebral anomaly, evoking malformations, disruptions, or fetal strokes. Since many or possibly all of these anomalies are thought to have a vascular origin, it seems appropriate to implicate prenatal exposure to vasoactive drugs.
Reflex sympathetic dystrophy syndrome of the lower limbs in renal transplant patients treated with cyclosporin A. In a 36-month period, 240 patients at our institution received kidney transplants from cadaver donors. Cyclosporin A (CsA) was used as the initial immunosuppressive therapy. Seven patients (5 men and 2 women) developed severe pain, periarticular soft tissue swelling with no effusion, and vasomotor changes in affected areas. Although articular mobility was conserved, most of the patients had great difficulty in walking. A patchy osteoporotic pattern was seen radiographically and increased uptake of 99mtechnetium with a periarticular distribution in the clinically affected areas were found. All of these symptoms and radiographic and scintigraphic signs are compatible with definite reflex sympathetic dystrophy syndrome (RSDS). Articular symptoms began within 3 months after kidney transplantation in all patients; all but 1 patient had plasma CsA levels greater than 200 ng/ml at that time. When the dosage of CsA was reduced, there was concomitant improvement in the RSDS, which appeared when the plasma CsA levels declined to less than 200 ng/ml. The mean duration of the clinical symptoms of RSDS was 8 months. We believe RSDS should be added to the list of complications that may appear in kidney transplant patients who receive CsA treatment.
Coronary hemodynamic effects of atrial natriuretic peptide in humans. Studies of the effects of atrial natriuretic peptide on the coronary circulation have yielded conflicting results in animals and have not been fully investigated in human subjects. To further characterize the direct coronary hemodynamic actions of atrial natriuretic peptide in humans and to assess the safety of its administration in patients with coronary artery disease, incremental doses of synthetic atrial natriuretic peptide and nitroglycerin were infused into the left coronary artery in 14 patients, 11 of whom had coronary artery disease. Both agents caused dose-related increases in total coronary sinus blood flow. The largest dose of atrial natriuretic peptide given to all patients (100 micrograms) increased mean coronary sinus blood flow from 127 +/- 7 to 149 +/- 9 ml/min (p less than 0.05) and decreased coronary vascular resistance from 0.93 +/- 0.07 to 0.81 +/- 0.05 mm Hg/ml per min (p less than 0.05); mean arterial blood pressure and heart rate were not affected by this dose of atrial natriuretic peptide. The greatest changes in coronary sinus blood flow (+25%) and coronary vascular resistance (-18%) after atrial natriuretic peptide administration occurred in the patients with coronary artery disease and no other associated cardiovascular disease. The maximal effects of atrial natriuretic peptide were similar to those of nitroglycerin, and no untoward effects were observed. Thus, atrial natriuretic peptide is a direct coronary vasodilator in humans. Its maximal dose effects are similar to those of nitroglycerin and were well tolerated in this small group of patients. The physiologic importance and therapeutic potential of atrial natriuretic peptide in patients with coronary artery disease merit further investigation.
Development of a highly efficient expression cDNA cloning system: application to oncogene isolation. We developed an expression cDNA cloning system capable of generating high-complexity libraries with unidirectionally inserted cDNA fragments and allowing efficient plasmid rescue. As an application of this system, a cDNA library was constructed from an NIH 3T3 transformant induced by mouse hepatocellular carcinoma DNA. Transfection of NIH 3T3 cells by the library DNA led to the detection of several transformed foci from which identical plasmids with transforming ability could be rescued. Structure and sequence analysis of the cDNA clones revealed that the oncogene was created by recombinational events involving an unknown gene and the mouse homologue of the B-raf protooncogene. Detection of the same genetic rearrangement in independent primary transformants implied that generation of the oncogene occurred within the tumor rather than during DNA transfection or cDNA library construction. The high frequency at which clones were identified and the large sizes of some of the transforming cDNA inserts isolated suggest wide applicability of this mammalian expression cloning system for isolating cDNAs of biologic interest.
Relationship between esophageal varices and azygos vein evaluated by cineportography. The relationship between esophageal varices and the azygos vein, which is generally considered to drain the major part of the variceal blood flow, was evaluated by percutaneous transhepatic cineportography in 35 patients with portal hypertension. We classified the patients into three groups. Those patients in whom most of the variceal blood drained into the azygos vein were designated the azygos-type group (n = 18). Those in whom most of the blood flowed into the brachiocephalic venous system were defined as the cervical-type group (n = 5), and those in whom the varices were drained by both the azygos vein and the brachiocephalic venous system were called the combined-type group (n = 12). Highly developed esophageal varices were recognized endoscopically in all patients in the combined-type and cervical-type groups, whereas some of the patients in the azygos-type group had less well-developed varices. In the azygos-type group, a tendency for the varices to be more severe as their drainage into the azygos vein became more cephalad was noted. Evaluation of the drainage of esophageal varices was considered useful not only for obtaining full comprehension of the significance of the azygos vein but also for assessing the suitability for sclerotherapy. Percutaneous transhepatic cineportography was useful for this purpose because it enables visualization of even the most minute amounts of blood flow.
Prospective quality-of-life analysis after palliative photoablation for the treatment of malignant dysphagia. Forty patients were treated for the relief of malignant dysphagia by using laser photoablation. Their quality of life was assessed before the start of treatment and at monthly intervals until death. Two methods were used, a physician's assessment (QL index) and a patient's self-assessment, the linear analogue self-assessment (LASA). There was significant correlation between assessments done at different times by different physicians (QL index rs, 0.786; P less than 0.001; LASA rs, 0.865; P less than 0.001). The correlation coefficient of the QL index and the LASA score with the patient's dysphagia grade was 0.459 and 0.336, respectively. The patient's swallowing ability, QL index, and LASA all were improved significantly at some time after laser therapy. The mean survival was 16 weeks with 58% of patients dying at home, 28% in the hospital, and 18% in a hospice. It was concluded that laser photoablation improves the overall quality of life in patients with malignant dysphagia.
Multimodal therapy for the management of localized Ewing's sarcoma of pelvic and sacral bones: a report from the second intergroup study. A total of 59 eligible patients with localized Ewing's sarcoma of the pelvic and sacral bones were entered into a multimodal Intergroup Ewing's Sarcoma Study (IESS-II) (1978 to 1982) and compared with a historical control series of 68 patients entered into an earlier multimodal Intergroup Ewing's Sarcoma Study (IESS-I) (1973 to 1978). High-dose intermittent multiagent chemotherapy (vincristine, cyclophosphamide, Adriamycin [doxorubicin; Adria Laboratories, Columbus, OH], and dactinomycin) was given to all patients for 6 weeks before and for 70 weeks following local therapy. All patients who had a tumor biopsy or incomplete resection performed received a dose of 55 Gy to the tumor bed. With a median follow-up time of 5.5 years, two of 59 patients (3%) had a local recurrence, five patients (8%) had a local recurrence and metastases, and 17 patients (29%) developed metastases only. There was significant statistical evidence of an advantage in relapse-free survival (RFS) and survival (S) for patients on IESS-II versus IESS-I, P = .006 and P = .002, respectively. At 5 years, the comparison between IESS-II versus IESS-I was 55% versus 23% for RFS and 63% versus 35% for S.
Ulcerated anogenital hemangioma of infancy. Ten female infants were referred for symptomatic hemangiomas in the anogenital area. (One had had steroid treatment prior to consultation.) The natural history of these lesions is well known. Virtually all will spontaneously involute over a period of years. However, the lesions reported were particularly troublesome because of repeated ulcerations and subsequent pain. Prior treatment had been local wound care with antibiotic ointment and Telfa-type dressings. After referral from a family practitioner or pediatrician, argon laser treatment was performed in an outpatient setting. Eight of the 10 patients were treated with local anesthesia, and 2 had general anesthesia. All lesions healed in 1 to 5 weeks. No patients referred during this period were excluded from this series. All who received treatment were included. All the lesions involuted following treatment. In our estimation, the final result is identical to what may be expected after spontaneous involution of an ulcerated or infected hemangioma. The major difference is that involution occurred in a few weeks in laser-treated patients rather than a period of months or years. Ulcerated hemangiomas of the anogenital area have significant morbidity that can be efficiently avoided with the use of argon laser therapy. Lesions of the anogenital area have a strong predilection for females.
Barrett's esophagus. A continuing conundrum. Barrett's esophagus, a condition in which the distal esophagus is lined by columnar epithelium, is almost always caused by gastroesophageal reflux and often occurs in conjunction with a sliding hiatal hernia. Patients are typically white men in their 50s who smoke and drink, and they present with complaints of regurgitation, heartburn, and/or dysphagia. Endoscopic biopsies are required to confirm the diagnosis. Complications, such as stricture, ulcer, dysplasia, and malignant degeneration, occur in many cases. Adenocarcinoma is the most serious complication. Medical treatment, including life-style changes as well as pharmacologic therapy, usually relieves symptoms and heals esophagitis, but when it fails, antireflux surgery is indicated. Patients without evidence of dysplasia should undergo endoscopy yearly; those with mild dysplasia require more frequent surveillance. If biopsies disclose severe dysplasia, esophagogastrectomy should be performed.
Volunteer participation in feeding residents: training and supervision in a long-term care facility. The increasing number of residents in long-term care facilities who require full and partial assistance during meals has created a need for volunteer support to enhance the quality of life for residents. The correlation between dependence in eating and the existence of swallowing disorders and the risk of aspiration in persons with swallowing disorders suggests that training must be given to volunteers who feed residents. A formalized program for volunteer training and supervision was implemented at Coler Memorial Hospital, a long-term care facility. The program's development and benefits are outlined. Implementation of this program resulted in better training of volunteers, increased socialization, communication, and safety for patients during meals.
The course of lymphocytic hypophysitis. A 27-year-old woman presented to our institution in her seventh month of pregnancy with complaints of headache and visual field disturbance. Workup revealed bitemporal hemianopia, a markedly enlarged pituitary gland on computed tomography scan, and biochemical evidence of partial hypopituitarism. At surgery, a biopsy specimen of the pituitary gland was taken revealing lymphocytic hypophysitis. The patient was treated with steroids and replacement doses of thyroid hormone. Visual fields improved postoperatively. A repeat computed tomography scan obtained 2 months after an uneventful pregnancy showed that her pituitary had regained normal size and contour. Over the next 9 months she had gradual recovery of all pituitary function. This case allowed us to follow and document the course of lymphocytic hypophysitis from its presentation as a macroadenoma with partial hypopituitarism to full recovery of both size and hormonal function of the pituitary. Lymphocytic hypophysitis should be considered in the differential diagnosis of a pituitary mass or pituitary dysfunction presenting in pregnancy. In patients with suspected lymphocytic hypophysitis and a pituitary mass, a trial of steroids may be therapeutic.
The Rex regulatory protein of human T-cell lymphotropic virus type I binds specifically to its target site within the viral RNA. The Rex protein of human T-cell leukemia virus type I (HTLV-I) was expressed in bacteria and partially purified. Rex was shown to bind in vitro specifically to an RNA sequence located in the 3' long terminal repeat of HTLV-I, named Rex-responsive element (RXRE). Rex also bound in vitro to the human immunodeficiency virus type 1 (HIV-1) Rev-responsive element (RRE), while purified HIV-1 Rev protein did not bind to the RXRE. The binding results obtained in vitro are therefore in agreement with the nonreciprocal function of Rev and Rex in vivo. Rex binds specifically to both RRE and RXRE and activates expression in both HIV-1 and HTLV-I, while Rev binds to RRE and activates only HIV-1. Binding of Rex to RRE deletion mutants previously shown to lack either the Rev-responsive or the Rex-responsive portion suggested preferential binding of Rex to a distinct target within the RRE. These results demonstrated that Rex, like Rev, acts by binding to a specific RNA target.
Twenty four hour heart rate variability: effects of posture, sleep, and time of day in healthy controls and comparison with bedside tests of autonomic function in diabetic patients. Heart rate variability was measured in 77 healthy controls and 343 diabetic patients by a count of the number of beat-to-beat differences greater than 50 ms in the RR interval during a 24 hour ambulatory electrocardiogram. In the healthy controls the lower 95% tolerance limits for total 24 hour RR interval counts were approximately 2000 at age 25, 1000 at 45, and 500 at 65 years. Six controls confined to bed after injury had normal 24 hour patterns of RR counts, while eight other controls showed loss of diurnal variation in both heart rate and RR counts during a period of sleep deprivation. RR counts in ten controls on and off night duty increased during sleep whenever it occurred. Nearly half (146) the 343 diabetic patients had abnormal 24 hour RR counts. The percentage of abnormal RR counts increased with increasing autonomic abnormality assessed by a standard battery of tests of cardiovascular autonomic function. A quarter of those with normal cardiovascular reflex tests had abnormal 24 hour RR counts. There were close correlations between 24 hour RR count results and the individual heart rate tests (r = 0.6). The assessment of cardiac parasympathetic activity by 24 hour RR counts was reliable. The diurnal variations in RR counts seen in the controls were probably related to sleep rather than either posture or time of day. The method was more sensitive than conventional tests of cardiovascular reflexes.
Ischemic colitis associated with dextroamphetamine use. Ischemic colitis can be caused by a variety of medications including a number of sympathomimetic agents. We report the case of a 47-year-old narcoleptic man who had abdominal pain and rectal bleeding. The clinical, radiographic, and histologic findings supported the diagnosis of ischemic colitis associated with oral dextroamphetamine use.