Melricflash/CW_MedAbstractsAlt huggingface dataset:
Effect of atenolol and diltiazem on heart period variability in normal persons. Several time and frequency domain measures of heart period variability are reduced 1 to 2 weeks after myocardial infarction, and a reduced standard deviation of normal RR intervals over a 24 h period (SDNN) is associated with increased mortality. The predictive accuracy of heart period variability may be reduced by drugs used to treat patients after myocardial infarction. Accordingly, a randomized, three period, placebo-controlled, crossover (Latin square) design was used to determine the effect of atenolol and diltiazem on time and frequency measures of heart period variability calculated from 24 h continuous electrocardiographic recordings during treatment with atenolol, diltiazem and placebo in 18 normal volunteers. During atenolol treatment, the 24 h average normal RR (NN) interval increased 24% (p less than 0.001). The three measures of tonic vagal activity were significantly increased (p less than 0.001) during atenolol treatment: percent of successive normal RR intervals greater than 50 ms = 69%, root mean square successive difference of normal RR intervals = 61% and high frequency power in the heart period power spectrum = 84%. Low frequency power also increased 45% (p less than 0.01), indicating that this variable also is an indicator of tonic vagal activity over 24 h. Diltiazem had no significant effect on the 24 h average NN interval or on any measure of heart period variability. The decreased mortality rate after myocardial infarction associated with beta-adrenergic blocker but not calcium channel blocker therapy may be attributed in part to an increase in vagal tone caused by beta-blockers. 

Category: cardiovascular diseases
The differentiation of delayed serologic and delayed hemolytic transfusion reactions: incidence, long-term serologic findings, and clinical significance. Delayed serologic transfusion reactions (DSTRs) and delayed hemolytic transfusion reactions (DHTRs) were studied in a large tertiary-care hospital. A DSTR was defined by the posttransfusion finding of a positive direct antiglobulin test (DAT) and a newly developed alloantibody specificity. A DHTR was defined as a DSTR case that showed clinical and/or laboratory evidence of hemolysis. Thirty-four cases of DSTR, 70 percent of which were due to anti-E and/or -Jka, were documented prospectively over a 20-month period. Retrospective review of the medical records found clinical evidence of hemolysis in only 6 (18%) of the 34. Thus, the incidence of DSTR was 1 (0.66%) of 151 recipients with posttransfusion samples available for testing, whereas the incidence of DHTR was only 1 (0.12%) of 854 patients tested. Fifteen of the 34 patients were followed for up to 174 days after reaction. Twelve of the 15 still demonstrated a positive DAT with anti-IgG only. Eluate studies indicated that the persistence of a positive DAT after DSTR or DHTR may involve several immunologic mechanisms, including the development of posttransfusion autoantibodies. This study indicates 1) that DSTRs are a frequent finding in multiply transfused patients, although most cases are benign and fail to meet rigid criteria for DHTR, and 2) that the persistence of a positive DAT after DSTR or DHTR is common. 

Category: general pathological conditions
Genetic control of the immune response in mice to Leishmania mexicana surface protease. Congenic mouse strains were tested in the lymphocyte proliferation assay for their response to the purified surface protease of Leishmania mexicana (gp63). The data obtained allow us to distinguish three different patterns of response, influenced both by H-2 (class II) and non-H-2 genes. Mice of the C57BL/10 (B10) background carrying H-2 haplotypes b,q, and r were found to be high responders; those carrying H-2 haplotypes d, j, v, and z were low responders; and those with H-2a, H-2f, H-2k, H-2p, and H-2u haplotypes were intermediate responders. Studies with H-2 recombinant strains indicated that the high responsiveness on the B10 background was determined by the Ab allele and the low responsiveness influenced by the Ad allele. Other genes besides H-2 appear to have a role in the immune response as shown by the fact that some strains with BALB, DBA, or C3H background differed in their pattern of responsiveness from B10 background strains carrying the corresponding H-2 haplotypes. By using recombinant protein, the influence of the leishmanial surface lipophosphoglycan that might co-purify with gp63, on the MHC restriction of the response to gp63 was excluded. The immune response to gp63 did not correlate with susceptibility of mouse strains to cutaneous infection with L. mexicana promastigotes. 

Category: general pathological conditions
Selective spatial attention in patients with visual extinction. The present study was designed to verify the attentional performance of patients with parietal lesions in the experimental condition in which they had to pay attention to 3 spatial positions located on the left, on the right and directly above the fixation stimulus (Experiment 1) and to only 1 of the 3 spatial positions at a time (Experiment 2). Twelve patients (6 subjects with right parietal lesions and 6 subjects without neurological deficits) participated in the experiment. The results of Experiment 1 showed that in patients with right parietal lesions the speed and accuracy of response to horizontally aligned stimuli increased gradually from right to left, whereas the control group showed only the effect due to the different retinal eccentricities of the 3 stimuli, that is, responses to central stimuli were faster and more accurate than responses to left and right stimuli. The results of Experiment 2 showed that both the neurological and control groups were faster to respond to central than to left and right stimuli, and that the neurological group was faster to respond to right than left stimuli, whereas no difference in RTs between two visual fields was obtained in the control group. Furthermore, when the patients had to respond to 3 spatial locations aligned horizontally (Experiment 1), the speed and accuracy of response to the right stimulus were the same as when they had to focus attention on it (Experiment 2). These results showed that the focus of attention in patients with visual extinction is on the rightmost stimulus and that the increased attention to the right is accompanied by a decreased attention to the left. 

Category: nervous system diseases
Drug-induced headache. Headache induced by medications used for nonheadache conditions, and more importantly, headache perpetuated by symptomatic medications used for primary headache disorders are discussed in detail in this article. The clinical features and mechanisms of drug-induced headaches are reviewed. Ergotamine and analgesic rebound phenomena are described. Management strategies for drug-induced headaches are outlined. 

Category: nervous system diseases
The stroke syndrome of striatocapsular infarction. Striatocapsular infarction has recently been described as a distinct stroke entity and forms an important subgroup of subcortical infarctions. In a prospective study of 50 consecutive patients over a 10 yr period with this syndrome, clinical and neuropsychological features, pathogenesis and outcome were studied to provide information concerning management and prognosis. The most common clinical presentation was that of a stroke affecting mainly the upper limb with cortical signs such as dysphasia, neglect or dyspraxia. Evidence from EEG, angiographic and neuropsychological data supported a vascular/haemodynamic basis for the presence of the acute neuropsychological changes, while the chronic changes were more likely to be due to diaschisis. A study of risk factors and cerebral angiography enabled 4 pathophysiological subgroups to be identified: (1) cardiac emboli to the origin of the middle cerebral artery; (2) severe extra-cranial cranial carotid artery occlusive disease with presumed embolism to the same site and/or involvement of haemodynamic factors; (3) proximal middle cerebral artery abnormalities causing occlusion of multiple lateral striate arteries at their origins; (4) normal angiography where pathogenesis was uncertain. The risk factors of cardiac disease and smoking were significantly increased as compared with age and sex-matched controls with other forms of ischaemic stroke. Stroke or vascular death rate was 2.7% per yr during a mean follow-up period of 2.25 yrs. Predictors of an excellent recovery with return to normal lifestyle were younger age, only brachial or brachiofacial weakness with absence of cortical signs at presentation and minimal change on angiography. This stroke entity deserves particular recognition in the spectrum of subcortical infarctions because of its specific pathogenesis, distinct neuropsychological features and reasonable prognosis. 

Category: general pathological conditions
Balloon rupture due to lesion morphology during coronary angioplasty. We report a case of coronary angioplasty of a left anterior descending artery lesion that was complicated by the rupture of three successive balloon catheters. Each rupture occurred as a pinhole jet of contrast into a diagonal side branch, causing subintimal staining. This case demonstrates that balloon rupture may result from lesion morphology. 

Category: cardiovascular diseases
Lipomatous hypertrophy of the interatrial septum: an unusual intraoperative finding. Lipomatous hypertrophy of the interatrial septum was an incidental finding in a man of 45 undergoing coronary artery bypass grafting for unstable angina. He was not overweight and did not have any rhythm disturbances. The diagnosis was made on frozen section. 

Category: cardiovascular diseases
Percutaneous balloon valvotomy for patients with mitral stenosis: initial and follow-up results. Percutaneous double balloon mitral valvotomy (PMV) was performed in 25 patients with severe mitral stenosis who were followed for at least 6 months after the procedure. There were 22 women and 3 men, with a mean age of 51 +/- 14 years (range, 27 to 74). Hemodynamic and angiographic findings were evaluated before and after PMV and clinical status was assessed at follow-up. There was a significant decrease in mitral gradient following PMV, from 15.4 +/- 5.1 to 5.0 +/- 2.6 mm Hg (p less than .0001); an increase in cardiac output, from 4.6 +/- 1.1 to 5.2 +/- 1.1 L/min (p less than .01); and an increase in calculated mitral valve area, from 0.9 +/- 0.2 to 2.2 +/- 0.6 cm2 (p less than 0.0001). Mitral regurgitation developed or increased in severity in six patients (24%). At the time of follow-up (mean, 12 +/- 5 months), three patients required elective mitral valve replacement for symptomatic mitral regurgitation and 91% (20 of 22) of the remaining patients had continued improvement in functional class. PMV can safely be performed in properly selected patients with symptomatic mitral stenosis with good immediate and follow-up results. 

Category: cardiovascular diseases
Loss of endothelium-dependent relaxant activity in the pulmonary circulation of rats exposed to chronic hypoxia. To determine whether exposure to chronic hypoxia and subsequent development of pulmonary hypertension induces alterations of endothelium-dependent relaxation in rat pulmonary vascular bed, we studied isolated lung preparations from rats exposed to either room air (controls) or hypoxia (H) during 1 wk (1W-H), 3 wk (3W-H), or 3W-H followed by 48 h recovery to room air (3WH + R). In lungs pretreated with meclofenamate (3 microM), the endothelium-dependent vasodilator responses to acetylcholine (10(-9)-10(-6) M) and ionophore A23187 (10(-9)-10(-7) M) were examined during conditions of increased tone by U46619 (50 pmol/min). Acetylcholine or A23187 produced dose-dependent vasodilation in control lungs, this response was reduced in group 1W-H (P less than 0.02), abolished in group 3W-H (P less than 0.001), and restored in group 3WH + R. In contrast, the endothelium-independent vasodilator agent sodium nitroprusside remained fully active in group 3W-H. The pressor response to 300 pM endothelin was greater in group 3W-H than in controls (6.8 +/- 0.5 mmHg vs. 1.6 +/- 0.2 mmHg, P less than 0.001) but was not potentiated by the endothelium-dependent relaxing factor (EDRF) antagonists: hydroquinone (10(-4) M); methylene blue (10(-4) M); and pyrogallol (3 x 10(-5) M) as it was in controls. It was similar to controls in group 3W-H + R. Our results demonstrate that hypoxia-induced pulmonary hypertension is associated with a loss of EDRF activity in pulmonary vessels, with a rapid recovery on return to a normoxic environment. 

Category: cardiovascular diseases
Near fatal subacute thallium poisoning necessitating prolonged mechanical ventilation. The authors describe a case of severe sensory-motor polyneuropathy caused by subacute thallium-intoxication rapidly progressing to respiratory failure due to complete muscle paralysis. After more than 2 months of mechanical ventilation, weaning from the ventilator was possible. Further intensive physical rehabilitation required an additional 6 months hospital stay, and 18 months later, neurological recovery was complete except for the distal lower limbs muscles. The authors discuss the different forms of thallotoxicosis and the present treatment is reviewed. Maximal prolonged therapeutic support should be offered in severe thallotoxicosis because of possible near complete recovery. 

Category: general pathological conditions
Cervicocephalic kinesthetic sensibility in patients with cervical pain. Head orientation in space makes use of multiple sensory afferents, among which the cervical proprioceptive cues could play a predominant role. To quantify the alteration of neck proprioception in patients with cervical pathology, we proposed a test for the clinical evaluation of the ability to relocate the head on the trunk after an active head movement, for 30 healthy subjects and 30 patients with cervical pain. The data demonstrated that this ability was significantly poorer in the patient group, indicating an alteration in neck proprioception. This test permits a discriminant classification of healthy and sick subjects, justifies proprioceptive rehabilitation programs, and allows a quantitative evaluation of their results. 

Category: nervous system diseases
Concurrent cisplatin, infusional fluorouracil, and conventionally fractionated radiation therapy in head and neck cancer: dose-limiting mucosal toxicity. After a preliminary dose-finding study involving 12 patients with advanced or locally recurrent head and neck cancer, 27 patients were treated on a phase II protocol, using fluorouracil 350 mg/m2/d by continuous intravenous (IV) infusion over 5 days, followed on the sixth day by a 2-hour IV infusion of cisplatin 50 mg/m2, administered during the first and fourth weeks of radiation therapy to total doses between 60 and 64 Gy, using 2 Gy daily fractions. Eight of these 27 patients had American Joint Committee on Cancer Staging (AJCC) stage III disease, and 12 had stage IV disease. Four had recurrent disease after surgery. Three-year follow-up is now available. Twenty-one (77.8%) remitted completely following treatment, and 11 remain free of local and regional relapse at 3 years. Four have developed systemic metastases. Following successful salvage treatment in two cases, estimated determinate survival at 3 years is 64%. Acute toxicity was manageable with this regime. Eleven instances of grade 3 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) mucositis were observed, which caused interruptions to radiotherapy in only four cases. No late sequelae have so far been recorded. It is concluded that the protocol described is tolerable but probably did not cause a greater number of locoregional "cures" than would have been expected following conventional radiotherapy alone in this group of patients. The use of infusional fluorouracil with concurrent conventionally fractionated radiation therapy and cisplatin infusion results in mucositis that limits the dose of fluorouracil to levels that are probably subtherapeutic. 

Category: neoplasms
Blood pressure level, trend, and variability in Dunedin children. An 8-year study of a single birth cohort In a birth cohort of children in the Dunedin Multidisciplinary Health and Development Study in New Zealand, resting blood pressures were recorded biennially five times from age 7 to 15 years. Using previously described methods, we examined the level, trend, and variability of blood pressures in those children with at least three readings. The level, trend, and variability of height, weight, and body mass index were compared among six separate groups of children. Two groups were categorized on the basis of high systolic pressure levels, one with low variability and the other with high variability, which was thought to resemble adult labile hypertension. Two additional groups were categorized on the basis of increasing and decreasing blood pressure trends; the fifth group had consistently low blood pressures, and the sixth group consisted of the remaining children. There were significant differences among the groups for the level of all the physical measurements and for the trend of body mass index. No significant differences were found among the groups for gender or socioeconomic status. A parental history of high blood pressure, stroke, or heart attack was significantly more common in the first two groups. 

Category: cardiovascular diseases
Sinus node-atrioventricular node isolation: long-term results with the "corridor" operation for atrial fibrillation The "corridor" operation is designed to restore sinus rhythm to patients with atrial fibrillation by electrically isolating the sinus node, a band of atrial tissue and the atrioventricular (AV) node from the remaining atrial tissue. Nine patients with drug-refractory atrial fibrillation underwent this operation; four patients had chronic atrial fibrillation and five had paroxysmal atrial fibrillation; the mean duration of symptoms was 12 +/- 8 years. Patient ages ranged from 25 to 68 years (mean 48 +/- 12). At preoperative electrophysiologic study, no patient had evidence of an accessory AV pathway or AV node reentry. Sinus node recovery time could not be determined in five patients because of recurrent atrial fibrillation during or before programmed stimulation. At operation the corridor of atrial tissue connecting the sinus and AV nodes was successfully isolated from the remaining left and right atrial tissue in all patients. One patient required early reoperation for recurrent atrial fibrillation before hospital discharge. At the predischarge electrophysiologic study, the corridor remained isolated in all patients except for one patient who had intermittent conduction between the corridor and excluded right atrium. One patient had nonsustained atrial fibrillation and one had atrial tachycardia evident in the corridor. Atypical AV node reentry of uncertain significance was induced in one other patient. Over a total follow-up of 191 patient months (mean 21 +/- 20), seven patients remained free of atrial fibrillation. Two patients had recurrent atrial fibrillation, which in one patient was effectively controlled by a single antiarrhythmic agent. A permanent pacemaker was implanted in four patients for sinus node dysfunction. 

Category: general pathological conditions
Adult immunization in a network of family practice residency programs. A substantial proportion of morbidity and mortality associated with vaccine-preventable diseases occurs among adults. Teaching residents about disease prevention is mandated in the curriculum guidelines for family practice programs. A cooperative study among the Kansas City family practice residency programs was begun to look at immunization behaviors in these teaching programs. A retrospective audit of medical records and a prospective survey of residents and faculty were performed. From the medical records of 400 patients seen for health maintenance examinations, the frequency of tetanus-diphtheria immunizations recorded was 4.75%. The pooled immunization rate recorded for pneumococcal vaccine was 25%, and for influenza vaccine, 24%. Although 93% of respondents knew patients need tetanus-diphtheria immunization every 10 years, on a written questionnaire giving clinical examples, they were less likely to elect to immunize older patients eligible for tetanus-diphtheria vaccine. The following immunization criteria were listed by respondents: for pneumococcal vaccine, age over 65 years (86%); for influenza vaccine, age over 65 years (85%), chronic diseases (69%), residence in a chronic care facility (7%), and being a health care worker (28%). Educational interventions stressing the appropriate criteria and involvement of the patient are planned at the separate programs. 

Category: digestive system diseases
Pathogenesis of ischemic necrosis in random-pattern skin flaps induced by long-term low-dose nicotine treatment in the rat. The objectives of the present experiments were to study the effects of long-term low-dose nicotine treatment on skin hemodynamics, viability, and microvascular morphology in 4 x 10 cm dorsally based acute random-pattern skin flaps in the rat. In addition, the reversibility of the nicotine-induced detrimental effects on skin-flap viability following cessation of nicotine treatment also was investigated. Low-dose nicotine (0.6 mg/kg) administered twice daily and subcutaneously for 24 weeks significantly (p less than 0.05) decreased skin-flap capillary blood flow, distal perfusion, and length and area of skin viability compared with the saline-treated control (n = 15). However, these same parameters in rats (n = 15) whose nicotine treatment had been withheld for 2 weeks prior to skin-flap surgery were not significantly different from the control, thus indicating that the detrimental effects of this long-term, low-dose nicotine treatment were reversible. The mean plasma level of nicotine in the nicotine-treated rats was 8.1 +/- 0.4 micrograms/dl and was within the range of plasma nicotine levels reported for human heavy cigarette smokers. Light and electron microscopic studies did not show evidence of histologic damage to the cutaneous microvasculature in acute random-pattern skin flaps and samples of normal (nonoperated) skin in nicotine-treated rats. It is concluded that long-term plasma levels of nicotine similar to those of heavy cigarette smokers are detrimental to the capillary blood flow and viability of random-pattern skin flaps in the rat. These deleterious effects can be avoided if skin flaps are raised 2 weeks after cessation of nicotine treatment. This low-dose nicotine treatment does not cause histologic damage to the microvasculature. Other pathogenic mechanisms of nicotine-induced skin flap ischemia are discussed. 

Category: cardiovascular diseases
Sinus arrest induced by trivial nasal stimulation during alfentanil-nitrous oxide anaesthesia. A case is reported of bradycardia and sinus arrest induced by insertion of a nasal temperature probe. Other possible causes of bradycardia and sinus arrest under anaesthesia are reviewed briefly. Evidence for the neurological basis of a nasocardiac reflex, similar to the oculocardiac reflex, is presented. A minor, trivial stimulus may elicit this reflex. 

Category: general pathological conditions