Melricflash/CW_MedAbstractsAlt huggingface dataset:
Thermal balance and tremor patterns during epidural anesthesia. Five healthy, nonpregnant volunteers were studied before and after induction of lumbar epidural anesthesia to determine the cause of central hypothermia during epidural anesthesia. Cutaneous heat loss was measured from 10 area-weighted sites using thermal flux transducers. Oxygen consumption was measured and converted to heat production in watts (W). After a 2-h control period at approximately 20 degrees C, epidural anesthesia was induced by injection of 30-50 ml 3% chloroprocaine. Additional boluses were given to extend the sensory blockade to at least the T5 dermatome. Tremor during epidural anesthesia was compared with normal shivering induced by rapid central venous infusion of approximately 4 l iced saline in six unanesthetized volunteers. Average skin temperature and cutaneous heat loss decreased during the control period, while tympanic membrane temperature remained stable. During the 1st h of epidural blockade, tympanic membrane temperature decreased 1.1 +/- 0.3 degrees C, and average skin temperature increased 0.9 +/- 0.5 degrees C. Cutaneous heat loss increased 16 +/- 6% (15 +/- 5 W), but metabolic heat production increased even more (and was associated with a shivering-like tremor). Tremor during epidural anesthesia and shivering induced by iced saline infusion had similar synchronous waxing-and-waning patterns. No abnormal EMG patterns were detected during epidural anesthesia. We conclude that central hypothermia during the 1st h of epidural anesthesia does not result from heat loss to the environment in excess of metabolic heat production, but results primarily from redistribution of body heat from central to peripheral tissues. Analysis of the tremor patterns suggests that oscillations recorded during epidural anesthesia in nonpregnant individuals is normal thermoregulatory shivering. Shivering occurred sooner and was more intense during iced saline infusion than during epidural anesthesia, despite comparable central hypothermia. The low intensity of shivering during epidural anesthesia, and in some individuals the delay in onset, may result from blockade of afferent cutaneous cold signals. 

Category: general pathological conditions
Association of Helicobacter pylori infection with dyspeptic symptoms in patients undergoing gastroduodenoscopy. PURPOSE: To determine the prevalence of Helicobacter pylori in patients with non-ulcer dyspepsia and ulcer disease as well as in a control population undergoing endoscopic retrograde cholangiopancreatography (ERCP) for suspected pancreatic or biliary disease. PATIENTS AND METHODS: Forty-six eligible patients undergoing upper endoscopy at Massachusetts General Hospital were studied over a period of 18 months, as well as 24 patients undergoing ERCP for presumed pancreatic or biliary disease. Two biopsy specimens from the fundus and two from the antrum were taken for microbiologic and histopathologic analysis. Sera were examined by enzyme-linked immunoabsorbent assay. All specimens were processed in a blind fashion. Chi-square test with Yates' correction was used for statistical analysis. RESULTS: H. pylori was found in 31 of 46 (67%) study patients and in six of 24 (25%) control patients (by microbiologic or histologic techniques) (p less than 0.01). H. pylori was found in all patients with peptic ulcer disease and in 60% of patients without ulcers. No association between H. pylori and any specific gastrointestinal symptom was observed. H. pylori was identified in the fundus as often as in the antrum, although in the antrum the organism was more often associated with histologic gastritis. Compared with histology, serologic assays for IgG and IgA antibodies to H. pylori had sensitivities of 100% and 94%, and specificities of 86% and 76%, respectively. Reexamination of selected specimens without knowledge of their identity revealed that the specificity of serology exceeded 94% while the sensitivity of histologic and microbiologic studies may have been closer to 80%. CONCLUSIONS: H. pylori was more common in dyspeptic patients than in our control subjects undergoing ERCP. Multiple biopsy sites from fundus and antrum are required to exclude infection. Serologies of IgG and IgA were sensitive and specific for H. pylori, suggesting a possible role for non-endoscopic diagnosis of this infection. The frequent association of H. pylori with active inflammation rather than with quiescent gastritis is consistent with a pathologic role of this organism. 

Category: general pathological conditions
Lymph node metastasis from papillary-follicular thyroid carcinoma in young patients. A total of 117 patients under 20 years of age with papillary and/or follicular thyroid cancer presented to the M. D. Anderson Cancer Center between 1949 and 1987. The most common presenting symptom was a cervical mass. Twenty percent of the patients had a history of prior irradiation. Sixty percent initially had palpable lymph nodes, while 26% who had clinically negative examinations had pathologically positive lymph nodes. Recurrence was highest in regional lymph nodes at 24%, with only a 4% recurrence rate at the primary site and a 3% recurrence rate at distant sites. There were no deaths due to the thyroid cancer. To maintain a low rate of recurrence, near-total thyroidectomy with neck dissection followed by iodine 131 treatment should be considered in these young patients. 

Category: neoplasms
Systolic hypertension in the elderly: reasons not to treat. Isolated systolic hypertension in the elderly is associated with increased morbidity and mortality. Accurate measurement of blood pressure in older patients is difficult. Therapy can be associated with various complications, and the special problems of the elderly, such as orthostatic hypotension and hyperkalemia, should be carefully considered. Drugs should be used in low doses and changes in dosage should be made infrequently. Patients should be monitored frequently for untoward effects of therapy. The benefits of blood pressure reduction and the optimal degree of blood pressure reduction remain unknown. 

Category: cardiovascular diseases
Ventricular ectopy: significance and management. Ventricular ectopy is a normal variant of cardiac rhythm, and its significance in an individual is related to cardiac risk factors and the presence or absence of heart disease. Although there is good evidence in many forms of heart disease that complex VEBs indicate a high risk of death, treatment of asymptomatic VEBs with antiarrhythmic drugs has not been shown to improve survival and may be hazardous. Treatment should be directed at the underlying heart disease. Those with heart disease and severe symptoms resulting from VEBs will often require electrophysiological assessment as to specific antiarrhythmic therapy. Those without heart disease can usually be managed by reassurance and do not require antiarrhythmic drugs. 

Category: general pathological conditions
Congenital duodenal diaphragm: conversion of stable chronic symptoms to subacute gastric outlet obstruction by penetrating foreign body. Congenital duodenal diaphragms (CDD) are rare lesions that usually become symptomatic and require surgery in childhood. We report a patient, who, although symptomatic since early childhood, had accommodated to the condition and finally required surgical correction in late life after an ingested foreign body traumatized the diaphragm, producing subacute gastric outlet obstruction. The condition, including the reconstruction of the precipitating event, was diagnosed endoscopically prior to surgery. 

Category: digestive system diseases
Proliferation and substrate effects on endothelial cell thrombogenicity. The effects of the cellular differentiation status and the adhesive-substrate on endothelial cell function in cell culture were measured with an enzyme based assay of surface thrombogenicity. A solid plastic, microporous polymeric, and fibronectin (FN) treated microporous polymeric were used as substrates for growth of endothelial cells. The microporous and FN treated synthetic substrates have been shown to aid in the induction of cellular differentiation mechanisms. Cells were studied under proliferative and nonproliferative growth conditions. The thrombogenicity of the surface created by the endothelial cell monolayers under various experimental conditions was determined using an enzyme based assay of fibrin deposition. Actively proliferating cells on the solid plastic substrate produced the most thrombogenic surface, while confluent endothelial cell monolayers grown on FN treated microporous substrate were the least thrombogenic surfaces. These data suggest that endothelial cell surface thrombogenicity is under substrate control, and also related to the cellular differentiation status. These findings are being used to design a novel approach to the small diameter synthetic vascular graft problem. 

Category: general pathological conditions
Diagnostic significance of flow separation within the carotid bifurcation demonstrated by digital subtraction angiography. The presence of an area of reversed blood flow due to flow separation in the interval carotid artery is a normal finding in Doppler ultrasound studies in vivo as well as in model carotid bifurcations. This flow separation phenomenon is caused by the geometry of the carotid bifurcation and the fluid dynamics of blood. We demonstrated the flow separation phenomenon on lateral-projection intra-arterial digital subtraction angiograms in 99 of 100 carotid bifurcations. The mean duration of flow separation was 5.8 seconds, with values up to 14 seconds in normal carotid bifurcations. The presence of this flow separation phenomenon is almost independent of atherosclerotic lesions and is not correlated with cerebral ischemia. Therefore, the angiographic finding of a flow separation has no diagnostic value. However, our results refer to a factor that may be important in the genesis of atherosclerosis at the carotid bifurcation, namely the duration of the stay of blood and its components within the area of flow separation. 

Category: cardiovascular diseases
Patterns of dyspepsia in patients with no clinical evidence of organic diseases. We studied 2000 dyspeptic patients with no obvious signs of organic disease at their first examination, in order to (1) verify how many diagnoses of idiopathic dyspepsia had really been made after exhaustive diagnostic procedures and (2) evaluate the diagnostic power of the symptoms in distinguishing organic from idiopathic dyspepsia. This latter was considered only when no structural abnormalities were found. In all the other cases, a distinction was made between "related" and "associated" organic dyspepsia according to whether or not there was a certain relationship between the abnormalities and the dyspeptic symptoms. The patients were referred to us as follows: (1) spontaneously, (2) sent by physicians collaborating with us, (3) referred to our open access endoscopic service. The results show the frequency of idiopathic dyspepsia was 26%, whereas associated structural abnormalities were present in 45.4%. Obvious organic causes of dyspepsia were seen in 28.6% (24% benign and 4.6% malignant diseases). When considered separately, no symptom alone allows a correct diagnosis. The simultaneous evaluation of the symptoms with linear discriminant analysis distinguishes between idiopathic and organic dyspeptic patients in about 70% of the cases. A higher discrimination percentage in about 70% of the cases. A higher discrimination percentage could probably be obtained using a wider range of clinical parameters and/or a more complex statistical analysis of the interrelationships which exist between the clinical symptoms and the final diagnosis. 

Category: general pathological conditions
Drug therapy for ventricular tachyarrhythmias: how many electropharmacologic trials are appropriate? To determine how many electropharmacologic drug trials should be performed to select therapy for patients with ventricular tachyarrhythmias, the outcome of 150 consecutive patients with inducible ventricular tachyarrhythmias undergoing serial electropharmacologic testing was examined. The probability of identifying predicted effective therapy (inductive of fewer than five ventricular responses with three ventricular extrastimuli at three pacing cycle lengths) and the probability of that therapy preventing sustained ventricular tachyarrhythmia recurrences were determined as a function of the number of preceding trials. The probability ( +/- SE) of identifying predicted effective therapy by the first trial (0.23 +/- 0.03) was significantly higher than that of the second (0.09 +/- 0.04), third (0.08 +/- 0.04) and fourth (0.05 +/- 0.04) trials (p = 0.001). No patient had predicted effective therapy identified by subsequent trials. The 2 year actuarial probability of freedom from sustained ventricular tachyarrhythmias on predicted effective therapy was higher for the first (0.79 +/- 0.08), second (0.73 +/- 0.13) and third (0.86 +/- 0.13) trials than for the fourth (0.33 +/- 0.27) trial (p = 0.02). Thus, the probability of selecting therapy with long-term efficacy was highest for the first trial (0.18), intermediate for the second (0.07) and third (0.07) trials and lowest for the fourth (0.02) and subsequent (0.00) trials. Accordingly, the electropharmacologic approach to therapy selection should be abandoned after three unsuccessful trials. 

Category: general pathological conditions
Seizures and other neurologic sequelae of bacterial meningitis in children. BACKGROUND. Although the mortality rate among children with bacterial meningitis has decreased dramatically in recent decades, some patients are left with neurologic sequelae. It has not been clearly established which features of the acute illness predict the chronic neurologic sequelae, including late seizures or epilepsy. METHODS. We followed 185 infants and children prospectively during and after acute bacterial meningitis. The mean duration of follow-up was 8.9 years (range, 0.1 to 15.5). During the first six years standard neurologic examinations were performed; telephone interviews were conducted thereafter. RESULTS. One month after meningitis, 69 children (37 percent) had neurologic abnormalities. Many of these signs resolved within a year, leaving only 26 children (14 percent) with persistent deficits: 18 (10 percent) had only sensorineural hearing loss, and 8 (4 percent) had multiple neurologic deficits. Thirteen children (7 percent) had one or more late seizures not associated with fever. The presence of persistent neurologic deficits indicative of cerebral injury was the only independent predictor of late afebrile seizures (P less than 0.001). CONCLUSIONS. After bacterial meningitis only children with permanent neurologic deficits are at high risk for epilepsy. Those with normal examinations after the acute illness have an excellent change of escaping serious neurologic sequelae, including epilepsy. 

Category: nervous system diseases
A case of massive true thymic hyperplasia with non-Hodgkin's lymphoma. A case of massive true thymic hyperplasia with non-Hodgkin's lymphoma of the mediastinum is reported in a 14-year-old boy. Computed tomographic scan of the chest showed a mass of the anterior mediastinum and conspicuous swelling of the lymph nodes in the upper and lower mediastinum. They were grossly resected. The tumor of the anterior mediastinum was histologically diagnosed as true thymic hyperplasia. All of the mediastinal lymph nodes were diagnosed as non-Hodgkin's lymphoma, diffuse, mixed small and large cell type. 

Category: neoplasms
Mechanism of intermittent preexcitation in the Wolff-Parkinson-White syndrome. The concept of electronically mediated conduction across an inexcitable gap. A man with intermittent preexcitation in the Wolff-Parkinson-White syndrome is reported. Once a sinus impulse was blocked in the accessory pathway, the block (ie, loss of preexcitation) was continued for a while until a PP interval reached or exceeded a critical period inducing sudden reappearance of preexcitation. This critical period was considerably longer than the effective refractory period of the accessory pathway. These findings are explained by the use of the concept of electronically mediated conduction across an inexcitable gap in the accessory pathway. It seems that when loss of protection was maintained, the sinus impulse was blocked at the site proximal to the gap, but the impulse passing through the atrioventricular node always reached retrogradely the site distal to the gap, and therefore, the next sinus impulse was blocked again. 

Category: cardiovascular diseases
Stress and sudden death. The case of the long QT syndrome. The idiopathic long QT syndrome (LQTS) represents a unique clinical example of stress-related sudden cardiac death. LQTS is characterized by the association of several distinctive electrocardiographic features, among which prolongation of the QT interval is the best known, with life-threatening arrhythmias that usually occur under conditions of physical or psychological stress. Effective therapies exist and are represented by antiadrenergic interventions; beta-adrenergic-blocking agents are the treatment of choice. When they fail, left cardiac sympathetic denervation has also proven to be very effective. The latter result suggests a role for alpha-adrenergic mechanisms in the arrhythmias of LQTS. The stressors more frequently associated with syncopal events in LQTS patients include fear, exercise fraught with emotions, swimming, and awakening because of a loud noise. Experimentally, life threatening arrhythmias have been induced during a highly emotional situation in conscious cats with normal hearts in which right stellate ganglia have been ablated, resulting in QT interval prolongation. This selective denervation creates a sympathetic imbalance of the type proposed by one of the pathogenetic hypotheses for LQTS. 

Category: general pathological conditions
The molecular genetic basis of Glanzmann thrombasthenia in the Iraqi-Jewish and Arab populations in Israel. Glanzmann thrombasthenia is an autosomal recessive bleeding disorder characterized by a decrease or absence of functional platelet glycoprotein (GP) IIb-IIIa (alpha IIb beta 3) integrin receptors. Although thrombasthenia is a rare disorder, its occurrence is increased in some regions of the world where intracommunity marriage and consanguinity are commonplace, resulting in increased expression of autosomal recessive traits. We have been studying two populations having an unusually high frequency of Glanzmann disease, Iraqi Jews and Arabs living in Israel, and were able to distinguish the populations on the basis of immunodetectable GPIIIa and platelet surface vitronectin receptor (alpha v beta 3) expression. In this article, we describe molecular genetic studies based on use of the PCR that have allowed us to characterize platelet mRNA sequences encoding GPIIb and GPIIIa from patients in these populations. In six of six Iraqi-Jewish families studied, cDNA sequence analysis identified an 11-base deletion within exon 12 of the GPIIIa gene. This mutation produces a frameshift leading to protein termination shortly before the transmembrane domain of GPIIIa. In contrast, a 13-base deletion encompassing the splice acceptor site of exon 4 of the GPIIb gene was found in three of five Arab kindreds studied. This deletion results in forced alternative splicing to a downstream AG acceptor, producing a 6-amino acid deletion in the GPIIb protein, including a single cysteine residue. These nucleotide sequence variations were exploited to design a rapid, PCR-based oligonucleotide dot-blot hybridization test for both pre- and postnatal diagnosis of Glanzmann disease. These studies demonstrate the heterogeneity of Glanzmann thrombasthenia in different populations, and its homogeneity within geographically restricted populations, and offer insight into the requirements for integrin surface expression. 

Category: general pathological conditions
Changes in ventricular fibrillation threshold during the development of perinephritic hypertension. Established hypertension is associated with enhanced susceptibility to life-threatening arrhythmias. However, little is known about the effects of the development of hypertension on the electro-physiological properties of the heart. To study this relationship, dogs were chronically instrumented for recording mean arterial pressure and conducting cardiac electrical testing during right ventricular pacing using an intracavitary bipolar catheter. In normotension, ventricular fibrillation threshold was determined under alpha-chloralose anesthesia, after which perinephritic hypertension was induced by wrapping one kidney in silk followed by contralateral nephrectomy. During serial testing of the same animals, ventricular fibrillation threshold was significantly increased early in the development of hypertension (2 to 3 weeks after renal wrapping), but found to be significantly reduced at 6 to 7 weeks after renal wrapping. The increase in ventricular fibrillation threshold was eliminated by cholinergic blockade. 

Category: general pathological conditions
Adjuvant, specific, active immunotherapy for resectable squamous cell lung carcinoma: a 5-year survival analysis. In 1976 Stewart et al. (Annals of the New York Academy of Sciences 277:436-466) reported the effectiveness of adjuvant specific active immunotherapy of lung carcinoma in improving the postoperative survival of stage I lung carcinoma patients in a phase II study using lung carcinoma-associated antigen (TAA) and complete Freund's adjuvant (CFA). A phase III study was then designed by the authors to see the effects of specific active immunotherapy compared to the conventional management (no treatment) and to nonspecific immunotherapy. From 1976 to 1981, 85 patients with resectable (stages I and II) squamous cell lung carcinoma were entered into a randomized study: 1) control group; 2) specific immunotherapy group--three monthly doses of 500 micrograms of TAA emulsified with CFA; 3) nonspecific immunotherapy group--three monthly doses of CFA emulsified in saline. All the patients in the study received skin tests with 100 micrograms of the same TAA used for the immunotherapy. Recently, a 5-year follow-up of all the patients became available: The life table 5-year survival of group 1 was 34%, of group 2 was 75%, and of group 3 was 53%. The median survivals for the three groups were group 1, 38 months; group 2, 106 months; and group 3, 71 months. The difference was significant at P = .007 (Cox-Mantel test). 

Category: neoplasms
Characterization of the effect of two 4-methyl piperidine derivatives of hemicholinium-3, A-4 and A-5, on choline transport. A-4 and A-5 are tertiary and N-methyl quaternary 4-methylpiperidine analogs of hemicholinium-3 (HC-3). Previous work in this laboratory has shown A-4 and A-5 to be inhibitors of the sodium-dependent, high affinity choline uptake system (SDHACU). Their effects on choline transport were characterized further using neuroblastoma 41A3 cells. These cells rapidly take up choline through two separate mechanisms: a SDHACU system and a sodium-independent, low affinity uptake system (SILACU). A-4, A-5 and HC-3 decreased 5 microM choline transport in a dose-dependent fashion. The compounds were unable to decrease choline transport at 250 microM choline suggesting that they are inactive with respect to SILACU. All three compounds significantly increased the Km but not the Vmax for the SDHACU system, suggesting a competitive mechanism of inhibition. Ki values ranged from 18 to 25 microM for A-4, 20 to 26 microM for A-5 and 68 to 75 microM for HC-3. Dose-response curves for inhibition of choline transport by A-5 and HC-3 were not changed by a 24-hr pre-exposure of the cells to each inhibitor. However, after a 24-hr pre-exposure to A-4, a significantly different dose-response curve was obtained compared to the dose-response curve for A-4 in untreated cells. After a 24-hr pre-exposure, a 4-hr recovery period was sufficient to remove the effect of each compound. These data suggest that A-4 and A-5, like HC-3, inhibit the SDHACU, competitively and reversibly. 

Category: neoplasms