Melricflash/CW_MedAbstractsAlt huggingface dataset:
Progress in cardioprotection: the role of calcium antagonists. Calcium antagonists are now widely used for the treatment of clinical hypertension and angina pectoris. They are efficacious for the treatment of vasospastic, fixed atherosclerotic and mixed angina; they reduce the incidence of silent ischemia; and they have been shown to reduce postmyocardial infarct angina. Experimental data suggest that they may have certain cardioprotective properties in cases of acute myocardial ischemia and infarction, stunned myocardium, diastolic dysfunction, left ventricular hypertrophy and atherosclerosis. Moreover, they have been shown to improve exercise performance, as well as the diastolic abnormalities in patients with hypertrophic cardiomyopathy. In animals, they may delay or reduce the extent of myocardial necrosis after coronary occlusion or coronary occlusion followed by reperfusion, and in low doses that do not alter the hemodynamic profile, they have been shown to enhance the return of ventricular function in animals with stunned myocardium. However, the early first-generation calcium antagonists (nifedipine, verapamil, diltiazem) have not been shown to reduce myocardial infarct size or to enhance survival in patients with acute myocardial infarction. There now are clinical studies that suggest that, unlike beta blockers or nitrates, nifedipine may slow the development of atherosclerotic progression in humans over a 2-year period, and it seems likely that in the 1990s there will be further expansion of the use of calcium antagonists for not only angina and hypertension but also for aspects of cardioprotection. That calcium antagonists may delay, prevent or possibly regress atherosclerotic lesions is an exciting possibility. 

Category: cardiovascular diseases
Potential role of IgG avidity for diagnosing toxoplasmosis. Sera from 20 cases of toxoplasmic lymphadenopathy were examined by an enzyme linked immunosorbent assay toxoplasma IgG avidity (ELISA) at two laboratories. The results obtained were largely in agreement and showed that sera from patients with acute infection had low avidity IgG (30% or less), whereas sera from patients with chronic infection had high avidity IgG (40% or more). It is suggested that this type of assay could have a useful complementary role in antenatal testing for toxoplasmosis. 

Category: general pathological conditions
Early and late effects of captopril treatment after large myocardial infarction in rats. The early (after 21 days) and late (after 4 months) effects of continuous treatment with captopril on left ventricular performance, weight and volumes were studied in rats with myocardial infarction. Early effects were examined in rats subjected to coronary ligation and randomized to either immediate treatment with captopril (2 g/liter drinking water) starting 2 h after surgery or no treatment. After 21 days, the treated group showed reductions in mean arterial, left ventricular systolic and left ventricular end-diastolic pressures compared with untreated rats. Right and left ventricular weight and left ventricular volumes were decreased and the ejection fraction index was increased by captopril treatment. To study the late effects of captopril, a second group of rats was randomized to immediate captopril treatment (starting 2 h after surgery), delayed captopril treatment (starting 21 days after surgery) or no treatment. When studied after 4 months of treatment, rats started on captopril treatment 2 h after infarction showed no differences compared with rats started on treatment 21 days after infarction. Treatment with captopril for 4 months produced changes that were similar to those in rats treated for 21 days. Captopril treatment improved hemodynamic function after myocardial infarction in rats examined after either 21 days or 4 months of treatment. The extent of the benefit was similar in the two treatment periods. Initiation of captopril therapy immediately after infarction did not appear to produce a greater effect than treatment started at 21 days after infarction in rats studied after the drug had been administered for 4 months. 

Category: cardiovascular diseases
Surgical management of cervical soft disc herniation. A comparison between the anterior and posterior approach. Anterior cervical fusion was initially described in the 1950s for cervical spondylotic radiculopathy. The indications for this procedure in the management of soft disc herniation have not been clearly defined. In addition, controversy exists as to whether a cervical soft herniation should be managed by an anterior approach or a posterior cervical laminotomy-foraminotomy. The authors report the results of a prospective study comparing anterior discectomy and fusion to posterior laminotomy-foraminotomy for the management of soft cervical disc herniation. Twenty-eight patients underwent anterior discectomy and fusion (Robinson horseshoe graft) while 16 patients underwent posterior laminotomy-foraminotomy. The disc herniations were classified into two types. Type I were single level anterolateral herniations (33 patients) while type II were central soft disc herniations (11 patients). Clinically, patients with type I herniations manifested signs and symptoms of radiculopathy while patients with type II herniations manifested signs of myelopathy or neck pain and bilateral upper extremity paresthesias in 4 patients. Confirmatory studies were myelography in 12 patients, myelography combined with computed tomography (CT) in 26 patients, and magnetic resonance imaging (MRI) in 6 patients. For type I herniations, 17 patients underwent anterior fusion while 16 patients had a posterior laminotomy-foraminotomy. The 11 patients classified as type II herniation all underwent anterior discectomy and fusion. There were 27 men and 17 women. The age range was 21 to 52 years (mean, 41 years). The follow-up was 1.6 to 8.2 years (mean, 4.2 years). 

Category: general pathological conditions
Oxygen supply and utilization relationships. A reevaluation. The relationship between oxygen transport (TO2) and oxygen consumption (VO2) has been studied in patients with a number of acute and chronic disorders. Many of these patients have been shown to have a linear relationship between these two variables over a wide range of TO2, which has been considered as evidence of pathologic supply dependency. This supply dependency contrasts with animal studies that have clearly demonstrated a biphasic relationship between TO2 and VO2. This review of the available data concerning the relationship between oxygen transport and supply under conditions of increased oxygen requirements and reduced oxygen transport suggests the possibility that the observed interaction in patients may, in many cases, represent the normal physiologic behavior of the system rather than an abnormal manifestation of impaired oxygen extraction. 

Category: cardiovascular diseases
Increased sensitivity to endotoxemia by tissue necrosis. In this study the interaction of endotoxemia and ischemic organ injury was investigated in a rat model. Animals received lipopolysaccharide to induce endotoxemia and were simultaneously subjected to renal ischemia. If only renal ischemia was induced, moderate azotemia occurred and all animals survived. Lipopolysaccharide treatment caused neither renal failure nor death. However, rats with both endotoxemia and renal ischemia showed severe azotemia, and 50% of the animals died within 48 hours. The observed mortality rate is unlikely related to renal failure since animals subjected to bilateral nephrectomy did not die within 48 hours after treatment with lipopolysaccharide. To further exclude the role of renal failure in the enhanced effect of endotoxemia, experiments were performed in which ischemic kidneys were excised from littermates and were placed in the abdomens of lipopolysaccharide-treated animals. A similar effect was observed: 50% of the animals died within 48 hours. Azotemia did not occur. Since tumor necrosis factor (TNF) is an important cytokine involved in endotoxemia-induced morbidity and death, we studied the role of TNF in our model. Plasma levels of TNF were increased during endotoxemia. Concomitant renal ischemic injury did not influence the concentration of TNF. When animals were treated with recombinant TNF and were subsequently subjected to renal ischemic injury, again a 50% mortality was observed, a rate similar to that in lipopolysaccharide-treated animals. We conclude that the sensitivity to endotoxemia is enhanced by tissue necrosis and may lead to death in the experimental model used in this study. 

Category: general pathological conditions
Quantification of leakage pressures after durotomy repairs in the canine. This study was undertaken to investigate the relative strengths of dural repair using standard suture techniques, suture supplemented with tissue adhesive, and tissue adhesive alone. Uniform 2 mm dural defects were created in adult beagles, repaired, and then subjected to pressurization testing. Defects repaired with suture alone initially leaked within the range of physiologic pressurization, while those supplemented with tissue adhesive or repaired with tissue adhesive alone failed at higher pressurization levels. Histologic sections obtained from the dura treated with fibrin adhesive sealant demonstrated minimal inflammatory response not significantly different than those sections examined at sites repaired by suture alone. A new substance, fibrin adhesive sealant, appears to be useful in effecting dural repair due to its ability to withstand pressures greater than those obtained with suture alone. 

Category: general pathological conditions
Evidence for hypomotility in non-ulcer dyspepsia: a prospective multifactorial study. A prospective multifactorial study of symptoms and disturbance of gastrointestinal function has been undertaken in 50 patients with non-ulcer dyspepsia. Objective tests including solid meal gastric emptying studies, gastric acid secretion, E-HIDA scintiscan for enterogastric bile reflux, and hydrogen breath studies were carried out in all patients and validated against control data. Gastroscopy and biopsy were carried out in non-ulcer dyspepsia patients only. Non-ulcer dyspepsia patients were categorised on the basis of predominant symptoms as: dysmotility-like dyspepsia (n = 22); essential dyspepsia (n = 14), gastro-oesophageal reflux-like dyspepsia (n = 11); and ulcer-like dyspepsia (n = 3). In the total non-ulcer dyspepsia population, solid meal gastric emptying was delayed (T50 mean (SEM) = 102 (6) minutes (patients) v 64 (6) minutes (controls), (p less than 0.01) and high incidences of gastritis (n = 26) and Helicobacter pyloridis infection (n = 18) were found. An inverse correlation was observed between solid meal gastric emptying and fasting peak acid output (r = -0.4; p less than 0.01). Indeed gastric emptying was particularly prolonged in eight patients (T50 mean (SEM) = 139 (15) minutes) with hypochlorhydria. In the non-ulcer dyspepsia population oral to caecal transit time of a solid meal was delayed (mean SEM = 302 (14) minutes (patients) v 244 (12) minutes (controls) (p less than 0.01]. Seven patients had a dual peak of breath hydrogen suggestive of small bowel bacterial overgrowth. No association was observed between symptoms and any of the objective abnormalities. 

Category: general pathological conditions
Integrated magnetic resonance imaging and phosphorus spectroscopy of soft tissue tumors. Eighteen patients with soft tissue masses underwent integrated magnetic resonance imaging (MRI) and phosphorus spectroscopy (31P-MRS) to evaluate benign and malignant tumor morphology and metabolism. Spectra from soft tissue tumors had a significantly higher proportion of phosphate in the low-energy portion of the 31P spectrum (P less than 0.001) with a concomitant decrease in phosphocreatine (P less than 0.01) compared with 31P spectra from normal muscle. Malignant tumors had a mean pH of 7.35 +/- 0.13 which was greater than that of muscle tissue with a mean pH of 7.08 +/- 0.07 (P less than 0.001). All tumors had greater relative levels of phosphomonoesters, inorganic phosphate, and phosphodiesters compared with those in muscle tissue but considerable variability among tumors was noted due to tumor size, extent of tumor necrosis, and muscle contamination. Integrated MRI/MRS studies are necessary to provide exact localization of the tumor and a more correct interpretation of the 31P-MRS data. 

Category: neoplasms
Enterogenous cyst of the cerebellopontine angle cistern: case report. A case of an enterogenous cyst located in the cerebellopontine angle cistern is presented. These cysts have usually been found in the spinal canal, and their intracranial occurrence is exceptional. In the present case, the cyst was lined histologically by a single epithelial layer of cuboidal cells with some glandular structures resembling the fundic glands of the stomach. The unusual location of the cyst and its histological features are discussed. 

Category: neoplasms
1,25-Dihydroxyvitamin D3 receptor RNA: expression in hematopoietic cells. 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] induces differentiation and inhibits proliferation of myeloid leukemic cells from various lines and patients; these effects are probably mediated through the 1,25(OH)2D3 receptor. Little is known of expression of 1,25(OH)2D3 receptor RNA in hematopoietic cells. We examined the expression and modulation of expression of 1,25(OH)2D3 receptor RNA in various proliferating and nonproliferating hematopoietic cells. Constitutive expression of 1,25(OH)2D3 receptor RNA was detected in various kinds of hematopoietic cells, including macrophages and activated T lymphocytes, as well as in cell lines KG-1 (myeloblasts), HL-60 (promyelocytes), ML-3 (myelomonoblasts), U937, THP-1 (monoblasts), K562 (erythroblasts), and S-LB1 (HTLV-1-transfected T lymphocytes). Receptor transcripts were 4.6 kilobases (kb), and no variant sizes were observed. All cell lines examined in this group also expressed 1,25(OH)2D3 receptors. Most B lymphocyte lines expressed negligible levels of 1,25(OH)2D3 receptor RNA and protein; however; analysis of a lymphoid/myeloid somatic hybrid suggested that suppression of expression of 1,25(OH)2D3 receptor RNA in B lymphocytes may be a dominant characteristic. HL-60 cells were cultured with 10(-7) mol/L 1,25(OH)2D3 for 24 to 72 hours, and levels of expression of 1,25(OH)2D3 receptor and its RNA were examined. Levels of RNA coding for the receptor were not modulated by exposure to high levels of ligand. Levels of occupied 1,25(OH)2D3 receptor protein increased in these HL-60 cells; but the total number of 1,25(OH)2D3 receptors decreased about 50% at 24 hours and returned toward normal at 72 hours. Steady-state levels of 1,25(OH)2D3 receptor RNA were not affected by terminal differentiation of HL-60 toward either granulocytes or macrophages. Nondividing macrophages from normal individuals also expressed 1,25(OH)2D3 receptor RNA. In contrast, nondividing peripheral blood lymphocytes from normal individuals did not express 1,25(OH)2D3 receptor RNA; with stimulation of proliferation of these cells, accumulation of 1,25(OH)2D3 receptor RNA increased markedly. Half-life (t1/2) of 1,25(OH)2D3 receptor RNA in T lymphocytes was short (1 hour) as determined by measuring decay of the message after addition of actinomycin D. Consistent with this short t1/2, accumulation of 1,25(OH)2D3 receptor RNA increased in cells as their protein synthesis was inhibited. Further studies are required to understand the physiologic role of 1,25(OH)2D3 receptors in myeloid cells and proliferating T lymphocytes. 

Category: neoplasms
Corticosteroid treatment reduces mast cell numbers in inflammatory bowel disease. Mast cell degranulation in the gut causes mucus secretion, mucosal edema, and increased gut permeability and may be responsible for some of the symptoms and signs of inflammatory bowel disease. We have used a novel monoclonal antibody (AAI) against tryptase expressed exclusively in the granules of mast cells to enumerate mast cells in rectal biopsies in order to study the effect of inflammatory bowel disease and drug treatment upon rectal mast cell numbers. Rectal mast cell numbers are significantly reduced in inflammatory bowel disease patients taking corticosteroids (mean 4.95 cells/mm2) when compared with control patients (10.1, P less than 0.001) and inflammatory bowel disease patients not taking corticosteroids (9.7, P less than 0.001 Wilcoxon rank sum test). The reduction in mast cell counts was independent of the degree of inflammation or architectural distortion. There was a negative correlation between the dose of corticosteroids and mast cell count (r = 0.53, P less than 0.05 Spearman rank correlation), and the mast cell count was reduced within a few days of treatment and remained low throughout steroid therapy. Mucosal mast cell depletion may be an important mechanism of action of corticosteroids in inflammatory bowel disease. 

Category: digestive system diseases
Effect of tamoxifen on serum insulinlike growth factor I levels in stage I breast cancer patients. Insulinlike growth factor I (IGF-I) has been shown to be a potent mitogen for breast cancer cells in vitro, and IGF-I receptors have been demonstrated on human primary breast neoplasms. In a randomized, placebo-controlled study, we document that administration of the antiestrogen tamoxifen to patients with breast cancer was associated with a statistically significant (P = .002) reduction in the serum level of IGF-I. The mean IGF-I level was 1.4 U/mL in the placebo-treated group and 0.9 U/mL in the tamoxifen-treated group. Because serum IGF-I level is growth hormone (GH) dependent and because data suggest that the pubertal surge in GH and IGF-I levels is sex steroid dependent, we speculate that the mechanism underlying our observation may involve blockade by tamoxifen of estrogen action in the hypothalamic-pituitary axis. We conclude that tamoxifen treatment reduces IGF-I levels and that this reduction may contribute to the therapeutic effect of the drug. 

Category: neoplasms
Hepatitis B virus integration in hepatitis B virus-related hepatocellular carcinoma in childhood. In Taiwan, hepatocellular carcinoma is one of the major malignancies in children between 5 and 14 yr of age. We studied the status of hepatitis B virus DNA in the hepatocellular carcinoma and nontumorous liver tissues of eight children with positive serum HBsAg and maternal HBsAg. The hepatocellular carcinoma tissues from five of the eight children showed integration of hepatitis B virus DNA into host cellular DNA sequences. A pattern of single-site integration in four children and a multiple-site integration pattern in one child were demonstrated. In the remaining three children, hepatitis B virus DNA could not be demonstrated in the tumor tissues. Using subgenomic fragments of the hepatitis B virus genome as probes, we found that the X gene fragment and the surface antigen gene fragment were the most conserved sequences. The single-site integration of hepatitis B virus DNA in childhood hepatocellular carcinoma may have hit the critical region, resulting in insertional mutagenesis and early development of hepatocellular carcinoma. With a short incubation period and less exposure to environmental carcinogens during early life, childhood hepatocellular carcinoma may provide a good model to study the carcinogenic potential of hepatitis B virus. 

Category: neoplasms
Relevance of intrinsic sympathomimetic activity for beta blockers. Intrinsic sympathomimetic activity (ISA) characterizes a group of beta blockers that are able to stimulate beta-adrenergic receptors (agonist effect) and to oppose the stimulating effects of catecholamines (antagonist effect) in a competitive way. Partial agonists are ligands that elicit a submaximal response when bound to beta receptors at maximal occupancy. In the isolated rat atrium, acebutolol produces a maximal stimulatory effect that is only 17 +/- 8% of the maximal effect induced by the full beta agonist isoproterenol. The presence of ISA results in less resting bradycardia and less of a reduction in cardiac output than is observed with beta blockers without ISA. In the long term, partial beta agonists may produce arterial vasodilation and increase arterial compliance, possibly leading to additional beneficial effects in the treatment of hypertension. beta blockers with ISA do not have adverse effects on plasma lipoproteins during long-term treatment; in addition, the presence of ISA could counteract the up-regulation of beta adrenoceptors often observed with beta blockers without ISA. Finally, the presence of ISA has been a conflicting issue for the use of such beta blockers in secondary prevention after myocardial infarction. However, the impressive results of the Acebutolol Prevention of Secondary Infarction trial in high-risk patients after myocardial infarction show that acebutolol, a beta blocker with moderate partial agonist activity, can be effective in decreasing the postinfarction mortality rate. By exhibiting a strikingly different hemodynamic profile from that of beta blockers without ISA, the partial beta agonists form an intriguing pharmacologic class of drugs for which prospective clinical trials should be extensively pursued. 

Category: cardiovascular diseases
Perioperative myocardial ischemia in patients undergoing noncardiac surgery--II: Incidence and severity during the 1st week after surgery. The Study of Perioperative Ischemia (SPI) Research Group. Because of the importance of postoperative myocardial ischemia and because substantial physiologic changes can occur for prolonged periods postoperatively, the incidence, severity and temporal course of myocardial ischemia were studied in 100 high risk patients during the 1st week after major noncardiac surgery. Electrocardiographic (ECG) changes consistent with ischemia were continuously monitored using ambulatory solid state ECG in the 100 patients with or at risk for coronary artery disease. Ischemic episodes were defined as reversible ST segment depression greater than or equal to 1 mm or elevation greater than or equal to 2 mm above the baseline value, with the baseline adjusted for respiratory and positional variation and temporal drift. All ischemic episodes were confirmed by three independent blinded investigators using hard-copy recordings. Total ECG monitoring time was 10,445 h. Twenty-seven patients (27%) developed 437 episodes of ischemia during the 1st week after surgery. The total duration of ischemia was 18,658 min, or 1.8 min of ischemia/h monitored. Ischemia was most severe during the early (days 0 to 3) versus late (days 4 to 7) postoperative period: 284 versus 153 episodes; 2.2 versus 1.2 min of ischemia/h. The greatest severity occurred on postoperative day 3: 109 episodes, 3.4 min of ischemia/h monitored, 1.5 mm mean ST change and 130 min mean duration. However, in 8% of patients, severe episodes also occurred late: postoperative day 6 = 44 episodes, 1.7 min of ischemia/h monitored, 1.3 mm mean ST change (59% greater than or equal to 2 mm) and 92 min mean duration. Most ischemic episodes (57%) were associated with tachycardia. 

Category: cardiovascular diseases
Strokes in African-Americans. Hypertension is the most important risk factor for stroke, especially in African-Americans. Improved control of high blood pressure nationwide is a key factor in the recent dramatic decline in stroke frequency, most notably in African-American women. Hypertension control programs must be adequately funded and expanded. African-Americans have a disproportionately high incidence of risk factors for stroke, including hypertension. There is evidence that the cerebral vessels involved in ischemic stroke in African-Americans may differ from those of Caucasians. There is an urgent need for more research on stroke in general, risk factor relations in particular, and mechanisms in the pathogenesis of stroke in African-Americans. 

Category: cardiovascular diseases