Melricflash/CW_MedAbstractsAlt huggingface dataset:
Non-vesicular release of glutamate from glial cells by reversed electrogenic glutamate uptake. Glutamate uptake into nerve and glial cells usually functions to keep the extracellular glutamate concentration low in the central nervous system. But one component of glutamate release from neurons is calcium-independent, suggesting a non-vesicular release that may be due to a reversal of glutamate uptake. The activity of the electrogenic glutamate uptake carrier can be monitored by measuring the membrane current it produces, and uptake is activated by intracellular potassium ions. Here we report that raising the potassium concentration around glial cells evokes an outward current component produced by reversed glutamate uptake. This current is activated by intracellular glutamate and sodium, inhibited by extracellular glutamate and sodium, and increased by membrane depolarization. These results demonstrate a non-vesicular mechanism for the release of glutamate from glial cells and neurons. This mechanism may contribute to the neurotoxic rise in extracellular glutamate concentration during brain anoxia. 

Category: general pathological conditions
Calcium and contractile responses to phorbol esters and the calcium channel agonist, Bay K 8644, in arteries from hypertensive rats. This study examined the calcium dependency of contractions in arteries from rats made hypertensive by aortic coarctation and in rats with genetic hypertensive (stroke-prone spontaneously hypertensive rats). Mesenteric artery and aortic strips were suspended in tissue baths for isometric force recording and contractions to two drugs were characterized: 1) a phorbol ester, TPA (12-O-tetrade-canoylphorbol-13-acetate), and 2) the calcium channel agonist, Bay K 8644. Thoracic aortae and mesenteric arteries from hypertensive rats were more sensitive to the contractile properties of the protein kinase C activator TPA than comparable arteries from normotensive rats. In thoracic aortae from coarcted rats, the contractile activity of Bay K 8644 was potentiated compared to normotensive values. In the presence of 19.2 mmol/L KCl, responses to Bay K 8644 in thoracic aortae from normotensive rats were potentiated and did not differ from coarcted values. In contrast, contractions to Bay K 8644 and TPA in abdominal aortae obtained below the coarctation were not different from normotensive values. Upon exposure to 26.2 mmol/L KCl, contractions to Bay K 8644 in abdominal aortae were potentiated and those in aortae from coarcted rats did not differ from sham values. Contractile responses to both drugs were blocked by nifedipine and verapamil and responses were attenuated in calcium-free solution. We conclude that calcium channel function and its regulation by protein kinase C contribute to altered vascular reactivity in hypertension. Further, these abnormalities have a pressure dependency, because they did not occur in abdominal aortae from coarcted rats. 

Category: cardiovascular diseases
Hyaluronan in pleural effusions and in serum. It has been suggested that a high level of hyaluronan (hyaluronic acid, HYA) in pleural fluid is an indicator of malignant mesothelioma. In 78 consecutive patients with pleural effusion of various causes the HYA concentration was measured in pleural fluid samples and in serum. Nine patients had malignant pleural mesothelioma, and in three of them the HYA level in pleural fluid was 100 mg/l or more. In 42 patients with effusions due to metastatic malignancy, the mean HYA in the pleural fluid was 75 mg/l, and in five the HYA level was above 100 mg/l. Cardiac insufficiency caused the effusion in 11 patients, of whom two had a level above 100 mg/l in pleural fluid. Four patients had a serologically confirmed viral infection and had HYA levels in pleural fluid of 8, 157, 335, and 554 mg/l, respectively. One patient had postinfectious effusion with an HYA level in pleural exudate of 748 mg/l, the highest in this investigation. Two patients had benign asbestos pleural effusions, and both had high pleural HYA levels (256 and 490 mg/l, respectively). The serum HYA values were much lower than in the pleural fluid, namely from 15 to 480 micrograms/l; the levels were independent of the levels in the pleural fluid. Thus, a high level of HYA in pleural fluid is not specific for mesothelioma but can occur in other malignant or benign diseases, and a low level does not exclude mesothelioma. 

Category: general pathological conditions
Reliability of death certificate diagnoses. Consistency between death certificates and clinical records from 5 general hospitals in Kuwait was studied for 470 deaths with the following underlying or associated causes: hypertensive (HYP), ischaemic heart diseases (IHD), cerebrovascular diseases (CVD) and diabetes mellitus (DM). Direct causes were not considered since they are of little interest analytically. Only deaths with definite or most probable ascertainment were included. One cardiologist, who was provided with the WHO criteria and relevant documents on death certification, independently reviewed the records. To test the reviewer's bias and the reliability of his judgement, an adjudication process was effected by having one senior cardiologist re-review a random subsample of 140 records. The two reviewers showed good agreement. Specific diagnoses criteria for deciding the underlying cause of death in multiple morbid conditions by the reviewer were followed. Due to possible reviewer bias, we aimed at measuring the difference between initial certifiers and the reviewer rather than measuring the diagnostic accuracy of initial certifiers in reference to the reviewer. The agreement index kappa showed poor agreement between original and revised certificates. The original certificates under-estimated CVD as an underlying cause of death by 69.2%, DM by 60%, IHD by 33.5% and HYP by 31.8% in our sample. Associated causes were also consistently under-estimated by initial certifiers as compared with the reviewer. This bias calls for basing mortality statistics in Kuwait on hospital death committees' reports rather than on initial certifier death certificates, use of multiple-causes of death instead of one underlying cause and adequate training of the medical profession on the value and process of death certification. 

Category: cardiovascular diseases
Increased platelet membrane sodium-proton exchange rate in spontaneously hypertensive rats. It has been proposed that increased Na-H exchange activity is involved in the pathophysiology of genetic hypertension. We studied platelets of spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto (WKY), and domestic Wistar rats (DWR), since platelets have similarities to smooth muscle cells and have been shown to have potentially related ion metabolism abnormalities, such as increased intracellular calcium activity. We determined the exchange rate by the intracellular acidification-dependent, extracellular sodium-dependent volume increase. The rate of increase during the first 3 min is linear and is shown to be higher in SHR (0.475 X min-1) than in WKY (0.410 X min-1) or DWR (0.389 X min-1). We conclude that the Na-H activity is increased in platelets of SHR. Similar findings in lymphocytes and neutrophils of SHR, and analogous findings in platelets of humans with essential hypertension, suggest that this abnormality is expressed by several cell types, some of which may be involved in the pathophysiology of genetic hypertension in both rats and humans. 

Category: cardiovascular diseases
The vascularized fibula graft in mandibular reconstruction. The use of a vascularized graft from the fibula for mandibular reconstruction is presented. The great strength, pliability, and long vascular pedicle that characterize such grafts make them particularly suitable for this type of repair. The results in six cases were highly satisfactory. Masticatory function was well restored, without alteration of the facial contour, and with minimal sequelae at the donor site. 

Category: neoplasms
Effects of doxazosin on blood pressure, renin-angiotensin-aldosterone and urinary kallikrein. Doxazosin, a new quinazoline-derivative postsynaptic alpha 1-adrenoceptor antagonist, was studied in this randomized, double-blind, placebo-controlled 12-week study. Its effects on blood pressure (BP), heart rate, metabolic functions and renal hormones were analyzed after administration of a single oral morning dose in a 3-phase fashion when administered to 17 patients (11 women, 6 men, 21 to 59 years) with mild to moderate uncomplicated essential hypertension. After titrating the antihypertensive effective dose biweekly from 1 to 8 mg/day and a mean end titration-point dose of 4.14 +/- 0.1 mg (mean +/- standard error of the mean) at week 8 of treatment, it was adjusted to maintain diastolic BP at levels less than or equal to 90 mm Hg for up to 12 weeks of treatment when, at a final mean dose of 4.35 +/- 0.2 mg/day, BP decreased in all patients by a mean 31 +/- 3/17 +/- 2 (supine) and 39 +/- 3/15 +/- 3 (standing) mm Hg (p less than 0.005) with no increase in heart rate and no "first-dose phenomenon." Neither the renin-aldosterone system nor electrolyte excretion was significantly affected. Renal function and metabolic parameters also remained unchanged. Urinary kallikrein excretion was augmented 2.47-fold (p less than 0.002). There was good tolerance; 1 patient discontinued the study because of dry nose. These results suggest that long-term monotherapy with doxazosin is an effective and safe antihypertensive agent for mild to moderate essential hypertension that stimulates urinary kallikrein excretion. 

Category: cardiovascular diseases
Effect of severe pulmonary hypertension on the calculation of mitral valve area in patients with mitral stenosis. We studied 50 consecutive patients with mitral valve stenosis (MS) by cardiac catheterization and Doppler echocardiography to assess whether the presence of severe pulmonary hypertension affected the calculation of valve area by Doppler pressure half-time method and by the Gorlin formula using pulmonary capillary wedge pressure as an index of left atrial pressure. Patients with severe mitral regurgitation were excluded. In patients with pulmonary artery systolic pressure (PAS) less than 70 mm Hg (n = 33), there was good correlation between the mitral valve area derived from Doppler echocardiography and from cardiac catheterization (r = 0.85). However, in patients with PAS greater than or equal to 70 mm Hg (n = 17), this correlation was not as good (r = 0.57). In these 17 patients, the Gorlin formula tended to underestimate the valve orifice area (mean valve area 0.85 +/- 0.49 and 1.06 +/- 0.46 cm2 by catheterization and by Doppler respectively, p = NS). Direct measurement of the valve area by two-dimensional echocardiography was possible in 12 of the 17 patients and correlated well with Doppler values (r = 0.91). Hence in the presence of severe pulmonary hypertension, Doppler pressure half-time estimation of mitral valve area is more accurate than is catheterization-derived valve area, using the wedge pressure and the Gorlin formula. 

Category: cardiovascular diseases
Lipomatous hamartoma of the orbit. Proliferations of mature adipose tissue, while common in retroperitoneal and subcutaneous sites, rarely occur in the orbit. We describe the clinical, radiographic, and histopathologic findings of a nonencapsulated lipomatous tissue overgrowth of the right orbit in a 35-year-old man. The mass had caused proptosis since childhood and was apparently present since birth. Due to the age at onset, the histologic similarity to normal orbital fat, and the lack of encapsulation or choristomatous elements, we propose the term lipomatous hamartoma for this entity. 

Category: neoplasms
Role of perfusion pressure and flow in major organ dysfunction after cardiopulmonary bypass. The role of perfusion pressure and flow during cardiopulmonary bypass with moderate hypothermia and hemodilution in the development of new postoperative renal or clinically apparent cerebral dysfunction was examined in 504 adults. Cardiopulmonary bypass flow was targeted at greater than 40 mL.kg-1.min-1 and pressure at greater than 50 mm Hg. Flows and pressures less than target occurred in 21.6% and 97.1% of patients, respectively. Fifteen patients (3.0%) suffered new renal and 13 (2.6%) new central nervous system dysfunction. Low pressure or flow during cardiopulmonary bypass, expressed in absolute values or in intensity-duration units, were not predictors of either adverse outcome. Multivariate analysis identified use of postoperative intraaortic balloon counterpulsation (p less than 10(-6], excessive blood loss in the ICU (p less than 10(-4], need for vasopressors before cardiopulmonary bypass (p less than 10(-4], postoperative myocardial infarction (p less than 10(-3], emergency reoperation (p less than 0.002), excessive postoperative transfusion (p less than 0.02), and chronic renal disease (p less than 0.03) as independent predictors of postoperative renal dysfunction. Independent predictors of postoperative central nervous system dysfunction were cardiopulmonary resuscitation in the intensive care unit (p less than 10(-6], intracardiac thrombus or valve calcification (p less than 0.02), and chronic renal disease (p less than 0.03). Age greater than 65 years (40.7% of patients) did not predict either outcome. We conclude that failure of the native circulation during periods other than cardiopulmonary bypass rather than the flows and pressures considered here is the major cause of renal and clinically apparent central nervous system dysfunction after cardiac operations. 

Category: cardiovascular diseases
A prospective randomized study of cerebrospinal fluid drainage to prevent paraplegia after high-risk surgery on the thoracoabdominal aorta. This article is concerned with the study of the effect of several variables, principally that of cerebrospinal fluid drainage, on the incidence of neurologic deficit in a prospective randomized series of patients with extensive aneurysms of the descending thoracic and abdominal aorta (thoracoabdominal type I and II). Forty-six patients had cerebrospinal fluid drainage, and 52 were controls, with a total of 98 available for study. Cerebrospinal fluid pressure was continuously monitored in the former group and pressure maintained less than or equal to 10 mm Hg in 20, less than or equal to 15 mm Hg in 20, and greater than 15 mm Hg in 6 patients during period of aortic clamping. The method of treatment including reattachment of intercostal and lumbar arteries (p = 0.2), temporary atriofemoral bypass during aortic occlusion (p = 0.3), and spinal fluid drainage (p = 0.8) were not statistically significant in reducing the incidence of neurologic deficits. Thus cerebrospinal fluid drainage as we used it, was not beneficial in preventing paraplegia. On appropriate statistical analysis we found that the only significant predictor of delayed deficits was postoperative hypotension (p = 0.006). 

Category: general pathological conditions
The perception of life events and daily stress in nonulcer dyspepsia. Previous studies on the association of nonulcer dyspepsia with major life events were performed without emphasis on the perception of these events, and have yielded conflicting results. The present study examined the perception of life events and, in addition, the role of daily "hassles" (stressful events) in patients with nonulcer dyspepsia. Thirty-three dyspeptic patients as defined by normal endoscopy and ultrasonogram and 33 controls of comparable sex, age, and social class were recruited for study. Both groups were asked to select from 56 major life events those they had experienced and to give a rating on how they perceived them. They were further asked to select similarly from 117 items of daily stress and to rate the severity of each item. The results demonstrated that the number of positive and negative events and the positive score were similar in both dyspeptic patients and controls, but dyspeptic patients had a higher perceived magnitude of negative events and a higher score of total life change as given by the summation of magnitude of positive and negative events (both p less than 0.05). The "hassles" scores were not significantly different between dyspeptic patients and controls. Analysis of individual life events revealed that dyspeptic patients had significantly (p less than 0.05) higher scores than controls in items of minor law violations, major change in closeness of family members, and major personal illness or injury. We conclude that patients with nonulcer dyspepsia have higher negative perception of major life events, which indicates that psychological factors may play a role in the pathogenesis of nonulcer dyspepsia. 

Category: general pathological conditions
Colobronchial fistula: a rare complication of Crohn's colitis. A 29-yr-old white woman presented with chronic pneumonia in the left lower lobe and with left pleural effusion. She was known to have inflammatory bowel disease, but she was asymptomatic under maintenance treatment with 5-ASA. She received numerous antibiotic regimens according to susceptibility testing of microorganisms cultured from sputum and bronchial lavage and on an empiric basis was also given antituberculosis treatment, but there was no clinical improvement or change in the chest radiographic findings. Sputum was repeatedly examined and yielded, among other organisms, Clostridium inocuum, Enterobacter, Klebsiella pneumoniae, Proteus mirabilis, and Staphylococcus aureus. On one microscopic examination of sputum, the presence of feculent material was suspected. A subsequent gastrografin enema revealed a cologastric and colobronchial fistula between the splenic flexture of the colon and the greater curve of the stomach and the bronchial system. Segmental resection of the colon and resection of the lower lobe of the left lung were performed. Histologic findings of the resected colon were consistent with Crohn's disease. After a long period of postoperative recovery, the patient returned to good general health and well-being. To our knowledge, a colobronchial fistula caused by Crohn's colitis has not been previously reported. 

Category: digestive system diseases
Verapamil increases serum alkaline phosphatase in hypertensive patients. In rats, verapamil decreases intestinal absorption of calcium, increases serum parathyroid hormone (PTH), and induces osteopenia. In this prospective study, verapamil 80-120 mg three times daily was given for 2 months to 20 patients with hypertension, and the effects on calcium homeostasis were recorded. This dose of verapamil significantly reduced supine systolic and diastolic blood pressure (+/- SD) from 158/100 +/- 9/8 mmHg to 146/89 +/- 14/8 mmHg (P = 0.001). Serum alkaline phosphatase (ALP) increased significantly from 2.77 +/- 1.06 mu kat l-1 to 3.19 +/- 1.22 mu kat l-1 (P = 0.004), and isoenzymes of ALP of skeletal origin appeared after verapamil treatment. The excretion of sodium in the urine increased (Na/creatinine ratio 8.95 +/- 6.01 before and 13.16 +/- 8.26 after verapamil; P = 0.04), while the excretion of calcium, phosphate and potassium was not changed. PTH was slightly increased at the end of verapamil treatment (1.09 +/- 0.54 vs. 0.98 +/- 0.74 microgram l-1; P = 0.07), and s-1,25(OH)2D3 was also somewhat increased (22.3 +/- 14.4 vs. 17.6 +/- 4.9 ng l-1; P = 0.26). Serum Ca was not affected by verapamil (before verapamil 2.43 +/- 0.11 mmol l-1, after verapamil 2.40 +/- 0.12 mmol l-1; P = 0.28). The increase in serum ALP demonstrates that verapamil affects bone cell metabolism in man. This effect could be secondary to the enhancement of PTH secretion. 

Category: cardiovascular diseases
Postmortem chorionic villus sampling is a better method for cytogenetic evaluation of early fetal loss than culture of abortus material. In utero chorionic villus sampling at the time of diagnosis of intrauterine fetal death is compared with more traditional use of cultured fetal skin, products of conception, or amniocentesis. A total of 102 specimens from early fetal losses were evaluated for success in karyotyping and chromosomal results. We found postmortem chorionic villus sampling is technically possible, offers the highest likelihood of getting a cytogenetic result, and is a rapid, reliable, and safe technique. The extraembryonic component of intrauterine fetal deaths appears to remain viable and continues to grow long after the embryo has died. Samples obtained at the time of diagnosis of fetal death offer the greatest changes of successfully obtaining a karyotype. The incidence of chromosome abnormalities associated with fetal loss, particularly trisomies, is higher than previous data suggested. 

Category: general pathological conditions
Glucose and fat metabolism during short-term starvation in cirrhosis. To evaluate the metabolic consequences of short-term (i.e., less than 24 hours) starvation, glucose and fat metabolism were studied in eight healthy subjects and in eight patients with stable cirrhosis after 16-hour and again after 22-hour starvation by 3-[3H]glucose and [14C]palmitate turnover and by indirect calorimetry. Although patients and controls showed significant increases in free fatty acid concentration (respectively, 48% +/- 12% and 53% +/- 17%) and turnover (55% +/- 14% and 71% +/- 21%) during short-term starvation, the values after 16- and after 22-hour starvation were higher in cirrhosis. Fat oxidation was enhanced in the patients, but did not increase during fasting in contrast to controls (increase 19% +/- 17%, P less than 0.05). Net glucose oxidation was decreased in postabsorptive cirrhotics (P less than 0.05). Although postabsorptive glucose turnover was not different from controls, starvation induced a greater decrease in glucose turnover in the patients (25% +/- 3% vs. 10% +/- 3%, P less than 0.05). This was not reflected in plasma glucose concentrations. In conclusion, the effects of starvation on glucose and fat metabolism are enhanced in cirrhosis; fasting hypoglycemia is prevented by decreased use of glucose. It remains to be established whether these changes are merely explained by defective liver function, per se. 

Category: digestive system diseases
Muscle fibre type and habitual snoring. Although anatomical abnormalities of the upper airway have been recorded in some patients with obstructive sleep apnoea (OSA), a muscle tone dysregulation also seems to have an important role in this disorder. Since habitual snoring is the initial stage of OSA, the structural characteristics of upper airway muscles (medium pharyngeal constrictor muscle [MPCM]) from 13 men (9 non-snorers and 4 habitual snorers) were studied. MPCM fibre structure in non-snorers was broadly similar to that in normal limb muscles, with the exception that fibre diameters were smaller for all fibre types. Compared with limb muscles, MPCM had a smaller proportion of type IIb fibres and a higher proportion of types I and IIa fibres. MPCM in habitual snorers had an abnormal distribution of fibre types (low percentage of type I and type IIb fibres and high percentage of type IIa fibres) compared with non-snorers (p less than 0.001) and the type IIa fibres were hypertrophic. No myopathic or neurogenic changes were seen. Two possible hypotheses explain the abnormal distribution of fibre types in snorers. First, a constitutionally determined reduction of slow alpha-motor neurons induces an adaptive transformation of type IIb to type IIa fibres and a hypertrophy of type IIa fibres; or, second, motor neurons change their patterns of discharge and, hence, of activation, and modify fibre-type distribution of MPCM as an adaptation to the anatomical characteristic of upper airway and habitual snoring. 

Category: neoplasms