shukoor65/lab-rag-model huggingface dataset:
Nutrition and hypertension prevention. Hypertension has been related to both obesity and a high salt intake. Evidence for the associations of blood pressure with body weight and dietary salt intake is summarized. In both adolescents and adults correlations between blood pressure and weight are highly significant, and in longitudinal studies change in blood pressure over time is correlated with change in weight. Correlations between salt intake and blood pressure are less striking, and the results of trials of modest salt restriction demonstrate a small but significant effect on blood pressure. Individuals vary in their susceptibility to salt, and hypertensive individuals are more responsive than normotensive individuals. Dietary deficiencies of potassium and calcium may amplify the effect of a high salt intake on blood pressure. Animal models provide compelling evidence for a genetic component to salt sensitivity of blood pressure. In two hypertension prevention trials, change in blood pressure was more convincingly related to change in weight than to change in dietary salt. Avoidance of obesity, or weight reduction in overweight individuals, should be key strategies for hypertension prevention. Avoidance of salt excess is also appropriate, although currently available trial data do not justify a recommendation of rigorous salt restriction for the entire population.
Intravascular ultrasound assessment of lumen size and wall morphology in normal subjects and patients with coronary artery disease. BACKGROUND. Necropsy studies demonstrate that coronary artery disease (CAD) is frequently complex and eccentric. However, angiography provides only a silhouette of the vessel lumen. Intravascular ultrasound is a new tomographic imaging method for evaluation of coronary dimensions and wall morphology. Few data exist regarding intravascular ultrasound in patients with CAD, and no data exist for subjects with normal coronaries. METHODS AND RESULTS. We used a multielement 5.5F, 20-MHz ultrasound catheter to examine eight normal subjects and 43 patients with CAD. We assessed the safety of coronary ultrasound and the effect of vessel eccentricity on comparison of minimum luminal diameter by angiography and ultrasound. Normal and atherosclerotic wall morphology and stenosis severity were also evaluated by intravascular ultrasound. The only untoward effect was transient coronary spasm in five patients. At 33 sites in normal subjects, the lumen was nearly circular, yielding a close correlation between angiographic and ultrasonic minimum diameter (r = 0.92). At 90 sites in patients with CAD, ultrasound demonstrated a concentric cross section; correlation was also close (r = 0.93). However, at 72 eccentric sites, correlation was not as close (r = 0.77). For 41 stenoses, correlation between angiography and ultrasound for area reduction was moderate (r = 0.63). In normal subjects, wall morphology revealed a thin (0.30 mm or less) intimal leading edge and subadjacent sonolucent zone (0.20 mm or less). Patients with CAD exhibited increased thickness and echogenicity of the leading edge, thickened sonolucent zones, and/or attenuation of ultrasound transmission. CONCLUSIONS. These data establish that intravascular ultrasound is feasible and safe and yields luminal measurements that correlate generally with angiography. Differences between angiographic and ultrasound measures of lumen size in eccentric vessels probably reflect the dissimilar perspectives of tomographic and silhouette imaging techniques. Intravascular ultrasound provides detailed images of normal and abnormal wall morphology not previously possible in vivo.
Epstein-Barr virus-associated peripheral T-cell lymphoma of activated CD8 phenotype. Two childhood cases are reported of peripheral T-cell lymphoma; the neoplastic cells expressed activated CD8 (T8) phenotype and contained Epstein-Barr viral (EBV) DNA. Both patients had an aggressive and rapid clinical course despite chemotherapy. Elevated titers of antibodies to EBV-viral capsid antigen (greater than 640) and early antigen (greater than 10) were found in both patients. Histology revealed pleomorphic immunoblastic lymphoma with extensive necrosis in one case and an angioimmunoblastic lymphadenopathy-like pattern containing Reed-Sternberg-like giant cells in the other. Southern blot hybridization studies showed clonal rearrangement of the T-cell-receptor beta gene in both cases, and a cytogenetic study on one case revealed clonal structure abnormality involving chromosomes 1, 6, 7, 10, and 19. Analysis of the tumor DNA showed a high copy number of EBV genome per cell compared with that of Raji and Marmoset B 95.8 lines; the study for human T-cell leukemia virus type I was negative. The EBV genome was found by in situ hybridization in the tumor nuclei in both cases. In addition to Burkitt's lymphoma, T-cell lymphoma of the helper phenotype, and Hodgkin's disease, EBV can contribute to the development of CD8-positive aggressive T-cell lymphoma.
An extensive transbasal approach to frontal skull-base tumors. Technical note. Lesions in the base of the frontal fossa have conventionally been approached extra- and intradurally through a bilateral frontal craniotomy. However, when the lesion is large or deeply situated, wider bilateral retraction of the frontal lobes is required to obtain a sufficiently large operative field. The authors describe a new operative approach for huge tumors at the frontal skull base, employing an en bloc bilateral osteotomy of the orbital roofs and frontal sinus. This procedure, which is a modification of the transbasal approach described by Derome and Guiot, is termed the "extensive transbasal approach." The advantages of this technique over conventional operative approaches are described.
The effect of high-dose steroids on MRI gadolinium enhancement in acute demyelinating lesions. Gadolinium (Gd) enhancement of brain lesions by MRI is a marker of active blood-brain barrier damage secondary to an inflammatory process. We studied the effects of high-dose (1,000 mg/d) intravenous (IV) methylprednisolone (Mp) for 4 to 8 days on Gd-enhancing lesions in seven patients with acute demyelinating diseases and compared pretreatment brain MRIs with studies obtained 1 to 4 days after treatment. Five patients had complete suppression, and two had significant suppression of Gd enhancement following treatment. In addition, six of seven patients had Gd-enhancing lesions that explained their clinical signs; in five of six of these patients, suppression of the Gd-enhanced lesions temporally correlated with clinical improvement. Thus, short courses of high-dose IV Mp suppress Gd enhancement in acute demyelinating lesions, and this correlates with clinical improvement.
Differentiation of HL-60 cells into cells with the osteoclast phenotype. The osteoclast is the unique multinucleated cell that is responsible for bone degradation in both physiological and pathological circumstances. However, knowledge of the lineage of this inaccessible cell, the nature of its precursors, and the regulation of its formation and activation is limited and controversial. Here we show that the human promyelocytic cell line HL-60 has the potential, under the appropriate culture conditions, to differentiate into cells that have morphological and functional characteristics of osteoclasts, including multinucleation, presence of tartrate-resistant acid phosphatase activity, cross-reactivity with monoclonal antibodies that preferentially recognize osteoclasts, and capacity to resorb bone and respond to calcitonin. The multinucleated cells also contain high affinity receptors to calcitonin, in contrast to wild-type undifferentiated HL-60 cells. These data suggest that osteoclasts share a common precursor with hematopoietic cells. These undifferentiated and differentiated HL-60 cells should provide a unique model for study of the cell biology of human osteoclast differentiation, allowing molecular biological and biochemical studies heretofore not possible.
Cancers of the maxillary sinus. Maxillary sinus cancers are rare as compared with cancers of other sites. Because the onset is insidious, they are at an advanced stage at diagnosis and therefore present a therapeutic challenge for local control. Traditionally, treatment has been surgery or irradiation, or a combination of the two. Local control and survival, however, remains poor. Numerous chemotherapeutic agents have shown activity against squamous cell cancers of the head and neck. In several studies the use of either neoadjuvant or concurrent chemotherapy has improved local control and survival when compared with historical controls. Randomized studies are needed to confirm the benefit of chemotherapy over the standard forms of surgical and radiation therapy.
Oral monomorphic adenomas. Monomorphic adenomas of the oral cavity have a predilection for the anterior mouth, particularly the upper lip. Two of the monomorphic adenomas, the inverted ductal papilloma and the canalicular adenoma, are biologically benign, but unfamiliarity with their histopathologic appearance can lead to a misdiagnosis of malignancy. The clinical and pathologic features of each are presented.
Patterns of blood-brain barrier breakdown in inflammatory demyelination. The evolution of the changes in the blood-brain barrier (BBB) in chronic relapsing experimental allergic encephalomyelitis (CREAE), a model of immune-mediated demyelination, has been studied by magnetic resonance imaging (MRI); gadolinium-DTPA (Gd-DTPA) was used to detect BBB breakdown by both quantitative and qualitative techniques. Animals with acute EAE were examined for comparison. In animals with CREAE an approximately linear relationship was found between the mean number of lesions enhancing with Gd-DTPA seen per MRI slice and the severity of clinical disability at relapse. In addition, a direct relationship was seen between the duration of clinical relapse and the duration of enhancement with Gd-DTPA for lesions associated with the relapse. Lesions studied in animals having entered a progressive phase of disease showed the most sustained BBB breakdown. These observations suggest that BBB breakdown is important in the development of clinical signs in inflammatory demyelination. In CREAE, areas of focal enhancement with Gd-DTPA could usually be clearly defined at a time of clinical relapse. In slices free of focal lesions, no abnormal Gd-DTPA leakage could be detected using a quantitative method. In contrast, in acute EAE no focal lesions were visible, but significant leakage was detected by measurement. No change was found in T2 relaxation times in CREAE or acute EAE. The pattern of BBB breakdown in inflammatory demyelination evolves from a diffuse shortlived disturbance in acute EAE to a more focal and prolonged breakdown in animals with chronic relapsing and progressive disease. The broad similarities in the pattern of BBB breakdown seen in CREAE and multiple sclerosis support the hypothesis that the initial vascular changes in the human disease are due to inflammation which could be mediated immunologically.
KTP laser stapedotomy: is it safe? Recent published concerns about the potential for visible light lasers to injure the inner ear have led to differing conclusions. While one has advised cautious application of a visible light laser, another eschewed visible light lasers in favor of the CO2 laser. Others have anguished over the efficacy of stapes surgeons as numbers of suitable candidates for otosclerosis surgery decline. In three years' experience with the KTP-532 laser, 80 primary and revision stapedotomies have been completed by this author. The author's experience with low morbidity and high air-bone gap closure rates are presented. The absence of apparent cochlear injury suggests that properly used KTP laser systems are safe. Competitive results were obtained with less than prolific numbers of stapes surgeries.
Effects of tissue-type plasminogen activator and anisoylated plasminogen streptokinase activator complex on mortality in acute myocardial infarction. An overview of eight randomized controlled trials of tissue-type plasminogen activator (Alteplase or Duteplase) and 10 of anisoylated plasminogen streptokinase activator complex (Anistreplase) showed that the odds of early death were reduced by 29% by tissue-type plasminogen activator and 46% by anisoylated plasminogen streptokinase activator complex, with overlapping 95% confidence intervals. Although the beneficial effects of both agents are consistent and are strengthened when all the trials are considered together, the available data do not permit comparisons of the relative efficacy of these two agents with each other or with streptokinase.
Clinical patterns and associated conditions in chronic uveitis. We determined the relative frequencies of the different types of chronic uveitis, and the possible associated conditions, among 400 consecutive patients with chronic uveitis examined during the years 1982 through 1988. Of the 400 patients, 183 (45.75%) had anterior uveitis, 98 (24.5%) ahd panuveitis, 61 (15.3%) had intermediate uveitis, and 58 (14.5%) had isolated posterior uveitis. Only four of the 98 patients with panuveitis (4.1%) were considered idiopathic after a comprehensive examination, whereas 94 of the 183 patients with anterior uveitis (51.4%) were similarly classified. We found an associated condition in 242 of the 400 patients of the study group (60.5%). Of these 242 patients, 61 had Behcet's disease, which constituted the most frequently encountered associated condition in this study. Of the 61 patients with Behcet's disease, 58 had panuveitis and constituted 59.2% of the panuveitis group. Of the 61 patients with intermediate uveitis, 17 (27.9%) had a concurrent disease. An associated condition was found in 95% and 96.2% of patients with unilateral and bilateral panuveitis, respectively, but in none of the patients with unilateral intermediate uveitis. Environmental, cultural, or genetic factors may be accountable for the differences discovered between our findings and those of previously published studies from the United States and England with respect to relative frequencies of some of the associated diseases in patients with chronic uveitis.
Postprandial hypotension: microneurographic analysis and treatment with vasopressin. To clarify the mechanism of postprandial hypotension (PPH), we made microneurographic analyses of patients with PPH and 10 healthy controls by recording multi-unit vasoconstrictive impulses of muscle sympathetic nerve activity (MSNA) directly from the tibial nerve fascicles during a glucose tolerance test. Oral intake of 75 grams glucose in 225 ml of water produced significant and prolonged hypotension in all patients and an increase in MSNA in all healthy subjects. Insulin and glucose responses were not significantly correlated with arterial blood pressure reduction. PPH was prevented by an infusion of vasopressin (0.3 U/min) given before glucose intake. These results suggest that PPH is caused by the lack of sympathetic compensation for the systemic hypotensive stress of splanchnic blood pooling that occurs after food ingestion, and that prior treatment with vasopressin reduces the portal venous flow by constricting the splanchnic vessels in patients with PPH.
Costal fringe. Costal fringe consists of a bandlike pattern of venous telangiectases along the anterolateral costal margins. It is a common and easily recognized entity, usually seen in elderly men. Association with underlying disease is not well established. To assess the frequency of costal fringe in a healthy young adult population, we examined 1523 active duty Air Force personnel (1203 men and 320 women) between the ages of 17 and 34 years. All subjects were human immunodeficiency virus seronegative; none had known hyperestrogenic or other disease states. Costal fringe was present in only three individuals, all men, a frequency of 0.2%. Costal fringe is a rare finding in healthy young adults.
Comparative evaluation of chenodeoxycholic and ursodeoxycholic acids in obese patients. Effects on biliary lipid metabolism during weight maintenance and weight reduction. Obesity is a condition associated with an increased frequency of gallstone disease. This study attempted to evaluate the comparative effects of two gallstone-dissolving agents, chenodeoxycholic acid and ursodeoxycholic acid, on bile acid metabolism and biliary lipid secretion in obese subjects in order to identify the bile acid of choice in preventing and treating gallstone disease in obesity. Twenty obese subjects (greater than 120% ideal body wt) were randomly treated with ursodeoxycholic acid (10 mg.kg-1.day-1.1 mo-1) and then with chenodeoxycholic acid (15 mg.kg-1.day-1.1 mo-1) or with chenodeoxycholic acid first and then with ursodeoxycholic acid. Patients 1-10 were studied while eating an unrestricted weight-maintenance diet, whereas patients 11-20 were eating a 1080-kcal/d hypocaloric diet. Biliary lipid composition, cholesterol saturation index, and biliary bile acid pattern were evaluated in all subjects before and after each treatment period; in subjects 6-10 and 16-20, biliary lipid secretion rates and bile acid pool size were also evaluated. Both ursodeoxycholic acid and chenodeoxycholic acid decreased cholesterol outputs and cholesterol saturation index. However, during the weight-maintenance period the decrease induced by chenodeoxycholic acid was not significant. Biliary cholesterol outputs and cholesterol saturation index were always lower during ursodeoxycholic acid administration than during chenodeoxycholic acid therapy. Ursodeoxycholic acid levels during ursodeoxycholic acid administration and chenodeoxycholic acid levels during chenodeoxycholic acid administration increased in bile to 50% and 77%, respectively, of total bile acid levels. Bile acid pool size remained unchanged during chenodeoxycholic acid administration and was significantly reduced by ursodeoxycholic acid administration during the weight-reduction period. In conclusion, ursodeoxycholic acid in obese subjects seems more effective than chenodeoxycholic acid, at least during weight maintenance, in reducing cholesterol saturation of bile. This effect is related to a significant decrease of biliary cholesterol output.
Insulin attenuation of vasoconstrictor responses to phenylephrine in Zucker lean and obese rats. Recent data from this laboratory indicate that insulin resistant obese Zucker rats exhibit hypertension associated with exaggerated in vitro vascular reactivity to phenylephrine, serotonin, and KCl, and we have found insulin to attenuate vascular reactivity responses to these agonists. Accordingly, in the present study we evaluated the possibility that exaggerated vascular reactivity responses in obese Zucker rats may result from insulin resistance and a consequent failure of insulin to attenuate vasoactive responses. Thoracic aortae were isolated from male 16 week old lean and obese Zucker rats, and replicate helical strips from each animal were suspended in a muscle bath under a resting tension of 1.4 g in the presence or absence of insulin (0.1 mU/mL) for 1 h. The insulin was then washed out, and vascular reactivity responses to phenylephrine were determined. The obese rats exhibited greater reactivity to phenylephrine (ED50:1.10 +/- 90 X 10(-8) v 7.57 +/- 0.88 X 10(-10) mol/L in lean and obese rats, respectively, P less than .025). Insulin caused a significant attenuation of the contractile response in both the lean and obese aortae. However, lean rats exhibited a markedly greater attenuation than the obese rats (46.0 +/- 17.0 v 17.8 +/- 7.5% attenuation in the lean and obese rats, respectively, P less than .01). These data suggest that increased vascular reactivity responses in obese Zucker rats may result from their insulin resistant state and, consequently, a diminished ability of insulin to attenuate vasoconstrictor responses.
Stimulation of protein synthesis in human tumours by parenteral nutrition: evidence for modulation of tumour growth. Eighteen patients with localized colorectal carcinoma were randomized to receive intravenous nutrition or to be fasted during the 24 h before surgery. Protein synthesis, an index of tumour growth, was then measured by the incorporation of [13C]leucine into tumour protein immediately before surgery. The mean (s.e.m.) rate of tumour protein synthesis in patients receiving nutrition (42.7(3.5) per cent per day) was 89 per cent higher than the rate in the fasted group (22.6(1.9) per cent per day) (P = 0.002). As tumours consist of a variety of different cell types, in vitro rates of protein synthesis were measured in malignant cells isolated from colorectal tumours and cultured with autologous serum obtained from the patient in either the fasted or the fed state. There was a mean increase of 81 per cent in protein synthesis when fed rather than fasted serum was used (P less than 0.02), indicating that the malignant cells themselves respond to nutrient supply. This increase in tumour protein synthesis provides the first evidence in vivo that the exogenous supply of nutrients can modulate the rate of growth of a human tumour.
The effect of sodium hyaluronate on the outcome of trabeculectomy. The outcome of trabeculectomy with the use of sodium hyaluronate was investigated in 99 trabeculectomies and compared with the results achieved in an earlier series of trabeculectomies without the use of sodium hyaluronate. The use of sodium hyaluronate facilitated performance of the surgery and tended to reduce the severity of postoperative shallow anterior chamber and intraoperative bleeding. It remains to be shown whether it also may prevent lens opacity increase.
Prevalence of primary fibromyalgia in the Finnish population. OBJECTIVE--To obtain descriptive epidemiological data on fibromyalgia and its components in a representative sample of the Finnish population. DESIGN--Cross sectional study of 8000 Finns aged 30 or more invited for screening and a main examination for musculoskeletal disorders and other major disorders. SETTING--A mobile clinic. POPULATION--7217 subjects who attended the screening phase; 3434 subjects positive on screening who attended the main examination for musculoskeletal disorders. MAIN OUTCOME MEASURES--Musculoskeletal, mental, and other symptoms detected by interview and questionnaire; results of standardised clinical examination of the musculoskeletal system; operational definition of fibromyalgia; mortality at 10 years. RESULTS--The prevalence of fibromyalgia was low (54 cases; 0.75%) and related to age (peak prevalence at 55-64 years), female sex (twice as prevalent in women), occupation (no cases among 1596 white collar professionals), level of education (strong inverse gradient), and high levels of physical stress at work. No significant associations were found with body mass index, smoking, or mental stress at work. The prevalence of fibromyalgia was sensitive to even minor modifications of the definition. Fibromyalgia was strongly coincident with many other disorders, especially musculoskeletal conditions. Fibromyalgia did not predict mortality. CONCLUSION--Descriptive epidemiological data offer little support for the concept of fibromyalgia.