shukoor65/lab-rag-model huggingface dataset:
Cardiac myofibroblasts express alpha smooth muscle actin during right ventricular pressure overload in the rabbit. A number of changes occur in contractile proteins and mechanical performance of the heart within 2 weeks of right ventricular pressure overload in 8- to 12-week-old rabbits. These changes are accompanied by increases in collagen concentration and the ratio of type I to type III collagen. The purpose of the present study was to evaluate the evolution of these connective tissue changes morphologically and to characterize the interstitial cells that might be responsible. The myocardium is infiltrated by mononuclear inflammatory cells 2 days after banding, accompanied by focal myocyte necrosis. By 7 days, the inflammatory infiltrates subside and the damaged myocytes seen at 2 days are replaced by new collagen and a population of spindle-shaped cells, with ultrastructural features of myofibroblasts. A significant proportion of these cells contain alpha smooth muscle actin by immunohistochemical analysis. At 14 days, there is a large increase in stainable collagen with complex remodeling and reduplication of the collagen fiber network of the interstitium. Alpha smooth muscle actin-containing myofibroblasts persist, but their immunoreactivity appears reduced compared with day 7. The authors hypothesize that the interstitial fibroblasts that acquire smooth-muscle-like features in this model play a critical role in the heart's response to severe and sudden mechanical stress and are at least partly responsible for the changes in connective tissue that occur as a result of pressure overload in this model.
Solitary polyclonal autonomous thyroid nodule: a rare cause of childhood hyperthyroidism. Solitary autonomous thyroid tumors are an unusual cause of hyperthyroidism, particularly in childhood. We describe the youngest individual so far reported with this condition, a 22 month child with a large hyperfunctioning thyroid nodule who became overtly hyperthyroid after iodinated contrast administration. The histology of the nodule was compatible with follicular cell hyperplasia. These tumors are often called toxic adenomas, although there is no solid evidence that they are true neoplasms. We examined the clonal composition of the child's thyroid tumor by X-chromosome inactivation analysis, taking advantage of a polymorphism in the X-chromosome gene phosphoglycerate kinase. The tumor consisted of an even mixture of cells containing activated paternal and maternal PGK alleles, indicating that the tumor was polyclonal. Furthermore, the nodule had no structural rearrangements or activating point mutations of ras oncogenes, which are found in up to 50% of solitary monoclonal follicular adenomas. Solitary hot nodules may at least in some cases be secondary to hyperplasia, and not to clonal expansion of an abnormal, mutated cell. This may also explain the relatively low frequency of malignant transformation observed in hyperfunctioning thyroid tumors.
Alteration of the pulsatile load in the high-altitude calf model of pulmonary hypertension. We compared main pulmonary arterial elasticity and global pulmonary arterial compliance in control and high-altitude (HA) calves to determine whether 1) changes in pulmonary arterial elasticity are contributing to an increase in the oscillatory load of the right ventricle in this model of pulmonary hypertension and 2) measured changes in stiffness of the HA calves' arterial wall are the result of both an increase in pressure and an alteration of the material properties of the HA calves' arterial wall. Newborn calves were placed at 4,300 m simulated altitude for 14 days, and control calves were kept at 1,500 m. The HA calves were then reacclimatized to 1,500 m for 24 h so that baseline pressures of the two groups were similar. Open-chest main pulmonary arterial and right ventricular micromanometric pressures, ultrasonic main pulmonary arterial diameter, and green dye flow were measured under baseline conditions and then under moderate and severely hypoxic conditions to make measurements at both baseline and increased pulmonary pressures. At elevated pressures, the pressure-diameter relationship was noted to be nonlinear, and a characteristic late systolic peaking of the right ventricular pressure waveform was seen. The Peterson pressure-strain modulus, pulse wave velocity, characteristic impedance, and global compliance (3 element windkessel) were calculated. The calculated variables were all shown to be pressure dependent, and no intrinsic differences in stiffness were seen between the control and HA animals when mean pressure was taken into account. Pulmonary arterial histology demonstrated, however, a characteristic increase in wall thickness in the HA animals. Thus, in this model of pulmonary hypertension, major changes in elasticity and pulsatile load are primarily due to an increase in pulmonary pressure. The structural changes present in the HA calves' arterial wall did not separately produce any measurable changes in arterial distensibility or the oscillatory load.
Behavioral audiometry. Behavioral audiometry is based on observation of overt responses to controlled auditory stimuli, as contrasted with electrophysiologic procedures, which involve electrophysiologic monitoring or direct recording of the bioelectric correlates of the original signal. When reinforcement is added to the behavioral procedures, the infant or young child provides highly reliable responses, and it is possible to test most infants 6 months of age and older with these procedures. The combination of both behavioral and electrophysiologic procedures can resolve most clinical questions regarding the auditory function of young infants and children.
Oral acyclovir therapy of recurrent herpes simplex virus type 2 infection of the hand. Acyclovir was evaluated as treatment of recurrent herpes simplex virus type 2 infection of the hand in a double-blind, placebo-controlled crossover study. In nine fully evaluable patients, oral acyclovir (2 g/day in three doses for 10 days) initiated during the earliest phase of a recurrence reduced the mean durations (+/- standard deviation) of clinical symptoms from 10.1 (+/- 3.6) to 3.7 (+/- 3.0) days (P = 0.008), signs from 11.1 (+/- 3.7) to 6.2 (+/- 3.3) days (P = 0.024), and viral positivity from 5.3 (+/- 3.8) to 0.6 (+/- 1.1) days (P = 0.011).
Patient-controlled analgesia. Does a concurrent opioid infusion improve pain management after surgery? OBJECTIVE.--To assess the influence of a continuous (basal) morphine infusion as part of a patient-controlled analgesia (PCA) system on the postoperative analgesic requirement and on recovery parameters following abdominal hysterectomy. DESIGN.--Single-center, randomized, controlled protocol. SETTING.--University medical center. PARTICIPANTS.--A total of 230 adult women were randomly assigned to receive no morphine infusion (control group) or a continuous 0.5-, 1.0-, or 2.0-mg/h morphine infusion. Each patient was able to self-administer supplemental intravenous bolus doses of morphine (1 to 2 mg) using a PCA infuser. MAIN OUTCOME MEASURES.--Use of the PCA device, opioid-related side effects, recovery times, and the patients' assessment of pain and sedation on linear visual analog scales were recorded during the 72-hour study period. Follow-up questionnaires were completed by the patients and their health care professionals to assess the overall adequacy of PCA therapy. RESULTS.--Patients who received the 2-mg/h morphine infusions received significantly more opioid medication 9 to 72 hours after their operation than those who received no infusion (control group). The presence of a continuous morphine infusion of 0.5 to 2 mg/h did not significantly decrease the number of patient demands or supplemental bolus doses administered compared with the control group. Overall, 168 (84%) of the 199 patients who completed the 72-hour study were able to achieve adequate analgesia without requiring changes in the PCA regimen or experiencing major side effects. Recovery times and outcome variables were similar in all four groups. CONCLUSION.--The routine use of a continuous opioid infusion in combination with a standard PCA regimen does not improve pain management compared with PCA alone after abdominal hysterectomy.
Leukaemia mortality among relatives of cystic fibrosis patients. A total of 219 families of patients with cystic fibrosis living in Wales were studied for the occurrence of other diseases and for cause of death, and the findings in relation to leukaemia are reported. There were eight deaths due to leukaemia, five of the myeloid type, in first and second degree relatives; this is significantly more than the expected on the basis of national age specific mortality rates. In comparison, mortality among siblings, parents, aunts and uncles, and grandparents from all causes was within the expected. Screening the five patients with myeloid leukaemia for the delta F508 mutation showed that four were carriers of this mutation. It is concluded that carriers of the delta F508 mutation may have an increased risk of developing acute myeloid leukaemia. This could happen through the direct effect of the cystic fibrosis gene itself, or through its influence on another gene, such as the met oncogene, or gene(s) involved in granulocyte function on the long arm of chromosome 7.
Subclinical cardiac dysfunction in sarcoidosis. Clinically apparent myocardial disease is infrequent in sarcoidosis. However, autopsy data show myocardial involvement in up to 30 percent of patients. Unexplained exertional symptomatology is a common complaint in patients with sarcoidosis. In this study, we investigated whether abnormal cardiac function might limit exercise performance in patients with sarcoidosis without overt cardiac involvement. We studied exercise responses in 35 patients with sarcoidosis and compared them with 28 untrained controls. Seventy-seven percent of the patients were symptomatic. Pulmonary function test results were lower in the group with sarcoidosis than normal controls, but they were within normal range. Only one patient had evidence of ventilatory limitation to exercise. Sixteen (46 percent) patients had abnormally increased heart rates (HRs) at rest prior to exercise testing and/or with exercise. Rapid HRs were confirmed during daily activities by continuous ambulatory electrocardiographic (ECG) monitoring. Left ventricular ejection fraction (LVEF) was measured to determine if systolic dysfunction could account for abnormal HR responses. Of patients with abnormally increased HRs, five had LVEFs less than 50 percent, and eight had normal LVEFs, of whom 75 percent had tachycardia at rest. Retrospective comparison of HR responses and LVEF between patients who did or did not receive corticosteroids revealed no significant differences between groups. We conclude that abnormal HR responses in patients without evident cardiac sarcoidosis are common and exertional symptoms in this population are often associated with chronotropic abnormalities. The exact mechanisms underlying the chronotropic abnormalities are unclear, but they likely include ventricular systolic dysfunction, sinus node dysfunction from granulomatous infiltration, or combinations of the two.
Effect of massive dose vitamin A on morbidity and mortality in Indian children The effect of vitamin A supplementation on preschool child morbidity and mortality was assessed in a prospective double-blind placebo-controlled study around Hyderabad, India. Every six months 200,000 IU vitamin A was given to 7691 children (treatment group) whereas 8084 children received a placebo (control group). Morbidity and mortality data were collected every three months. Risk of respiratory infection was higher in children with mild xerophthalmia than in children with normal eyes. Vitamin A supplementation had no effect on morbidity status. Mortality rates were similar in the two groups; it was highest in children who did not receive either vitamin A or placebo. The findings suggest that vitamin A supplementation alone may not reduce child mortality.
Origin of malignant centrofacial granulomas: surface markers and gene rearrangement of malignant cells. Malignant centrofacial granuloma (MCFG) is a clinical entity characterized by a relentless ulceration of the upper airway involving the nose, palate, and face, without any demonstrable etiology. The origin of 11 cases were analyzed with the help of cell-surface immunostaining in all and with T-cell receptor gene (TCR) rearrangement in 3. The results show that most of the cases of MCFG are in fact T-cell lymphomas with cell-surface antigens (CD2, CD7, CD3) consistent with either early or mature T lymphocytes. However, some cases exhibit B-lymphoid (CD19, CD20) or histiomonocytic (CD13, CD14) lineage-specific markers. In conclusion, despite its remarkable clinical unity, MCFG is a heterogeneous group of neoplastic diseases, most but not all of which may be classified as T-cell lymphoma.
Popliteal aneurysm with spontaneous arteriovenous fistula. This report documents a rare manifestation of aneurysmal disease of the popliteal artery. We describe a popliteal aneurysm presenting with acute venous hypertension due to a spontaneously occurring arteriovenous fistula. The fistula was defunctionalized by treating the aneurysm with a standard technique of exclusion and bypass with resolution of the symptoms of venous hypertension and maintenance of normal distal perfusion.
Extraocular muscle surgery in myasthenia gravis. Myasthenia gravis is typically a disease of young people in active employment who need a field of binocular single vision. Although it is systemically controllable with a good chance of spontaneous remission, persistent loss of binocularity may cause chronic disability. We report our experience of extraocular muscle surgery in five patients with stable myasthenia gravis and persistent double vision. Extraocular muscle involvement was selective, giving rise to incomitant and concomitant squints, with individual muscle overactions as well as underactions. Treatment was by conventional recession and resection procedures with the additional use of Faden and adjustable sutures where appropriate. In all five cases a larger, stable field of binocular single vision was established. It is concluded that extraocular muscle surgery may be beneficial in selected cases of myasthenia gravis.
A comparison of sucralfate with placebo in the treatment of esophageal ulcers following therapeutic endoscopic sclerotherapy of esophageal varices--a prospective controlled randomized trial. In 1984 Roark published the first report of a sucralfate treatment of esophageal ulcers after sclerotherapy. Because this was an uncontrolled trial we planned a prospective double-blind placebo-controlled study with 60 patients. After therapeutic paravariceal injection-sclerotherapy of esophageal varices, patients were randomly treated with sucralfate suspension or placebo. Time of treatment was limited to a maximum of 3 weeks and the dosage of sucralfate was 1 g q.i.d. (Ulcogant-Suspension). Healing was assessed by endoscopy at weekly intervals. Fifty-three patients (25 sucralfate, 28 placebo) were evaluable according to the protocol. No patient left the study because of side effects. At the start of the trial, the patients in the sucralfate group showed a larger ulcer area than the placebo group. There was a tendency to faster healing in the sucralfate group, especially in patients with deeper ulcerations. However, there was no significant difference in global healing between both treatment groups after 3 weeks. Sucralfate suspension may be of value in accelerating the healing process in esophageal ulcers after sclerotherapy, especially in patients with deep ulcers. These results should be confirmed in further trials, in which patients should be stratified with respect to their ulcer volume and severity of liver disease.
Orthostatic vital signs in emergency department patients. STUDY OBJECTIVE: To examine the variability and define the normal ranges of orthostatic vital signs in an emergency department population. DESIGN: Descriptive. TYPE OF PARTICIPANTS: Adult ED patients with no history of recent blood or fluid losses. MEASUREMENTS: Lying and standing heart rate and blood pressure measured by an automated instrument. RESULTS: In 132 presumed euvolemic patients, the statistical normal ranges (mean +/- 2 SD) of orthostatic vital signs were wide: on standing, the heart rate range was from decreases 5.0 to increases 39.4 beats per minute; for systolic blood pressure, the range was decreases 20 to increases 25.7 mm Hg; and for diastolic blood pressure, the range was decreases 6.4 to increases 24.9 mm Hg. In this sample, 43% had "positive" orthostatic vital signs according to currently accepted values. CONCLUSION: The data from this study indicate that there is a wider than expected variation in orthostatic vital signs among presumed euvolemic ED patients.
Prognosis of symptomatic duodenal adenomas in familial adenomatous polyposis. The frequent association between familial adenomatous polyposis and duodenal tumors is increasingly recognized, yet many patients do not benefit from adequate diagnosis and follow-up of upper gastrointestinal polyps. A retrospective review of 14 patients with duodenal tumors associated with familial adenomatous polyposis was undertaken to assess the impact of early diagnosis by screening asymptomatic patients. Six of eight patients presenting with symptoms suggesting duodenal disease had invasive cancer. Four of these six patients died after surviving a mean of 13 months after diagnosis. In contrast, none of the six patients diagnosed after screening with upper gastrointestinal endoscopy has had invasive carcinoma. Early diagnosis and long-term surveillance of asymptomatic patients with familial adenomatous polyposis affords the opportunity to diagnose and treat duodenal tumors at an early stage, thereby, avoiding the dismal prognosis once invasive cancer has developed.
Triiodothyronine-enhanced left ventricular function after ischemic injury. Hypothyroidism is associated with profound left ventricular dysfunction. Brain-dead organ donors and patients undergoing cardiopulmonary bypass are chemically hypothyroid with significantly reduced circulating free triiodothyronine (T3). To test the hypothesis that T3 enhances left ventricular function in a hormonally deficient environment, a total of 36 healthy New Zealand White rabbit hearts were studied using a modified Langendorff preparation with Krebs-Henseleit perfusate and intra-ventricular balloon. In 9 normal rabbit hearts a cumulative dose-response curve with logarithmically increasing doses of T3 was obtained. The vehicle solution for T3 dissolution served as control (n = 9). Left ventricular function was assessed from peak developed pressure at baseline and after T3 administration. Triiodothyronine had no effect in normal hearts on peak developed pressure or end-diastolic pressure. In 18 rabbits, the acute effect of T3 administration after ischemia was investigated. Preischemic left ventricular function was measured to serve as baseline, and hearts were subjected to 37 degrees C global ischemia. Triiodothyronine (n = 9) or vehicle (n = 9) was infused during reperfusion, and left ventricular peak developed pressure was measured at 30 and 60 minutes of reperfusion. Recovery of function (expressed as percent return of left ventricular peak developed pressure) was significantly improved within 15 minutes of reperfusion (65.0% +/- 2.1% versus 80.2% +/- 4.1%) and remained significantly improved throughout the reperfusion period (p less than 0.05 by analysis of variance). These data suggest that although T3 possesses no inotropic properties, it significantly improves postischemic left ventricular function. The rapidity of the functional improvement suggests that these effects may be due to plasma membrane-mediated mechanisms.
Brain protection during circulatory arrest. Previous nuclear magnetic resonance studies in this laboratory have shown a beneficial biochemical effect of antegrade cerebroplegia (CP-A) during hypothermic circulatory arrest. This study compared CP-A with other methods of cerebral protection during hypothermic circulatory arrest to assess the clinical utility of this technique. Twenty-three sheep were divided into four groups: systemic hypothermia alone (SYST) and systemic hypothermia combined with external cranial cooling (EXTNL), retrograde cerebroplegia (CP-R), or CP-A. Cardiopulmonary bypass was started, and the sheep were cooled to 15 degrees C and subjected to 2 hours of circulatory arrest. Cardiopulmonary bypass was restarted, and the animals were rewarmed and weaned from cardiopulmonary bypass. Serial neurological examinations were performed and hourly scores assigned until the animals were extubated. Postanesthetic neurological scores improved in all groups throughout the 6-hour recovery period except the CP-R group. The improvement over time for these scores was similar for the EXTNL and CP-A groups and significantly better than for the SYST or CP-R groups (p = 0.004). The CP-A group had 5 of 7 animals with deficit-free survival despite the similarity in recovery of baseline brainstem function. We conclude that both antegrade infusion of cerebroplegia and external cranial cooling confer distinct cerebroprotective effects after a protracted period of hypothermic circulatory arrest when compared with the other methods studied.
Diagnosis of cerebral amyloid angiopathy by enzyme-linked immunosorbent assay of cystatin C in cerebrospinal fluid. An abnormally low level of cystatin C in the cerebrospinal fluid is a diagnostic marker for the hereditary form of brain hemorrhage associated with amyloidosis that was first identified in Iceland. We developed an assay for cystatin C to use in the diagnosis of patients with cerebral amyloid angiopathy and brain hemorrhage. This test consists of a sandwich enzyme-linked immunosorbent assay using monoclonal mouse anticystatin C and polyclonal rabbit anticystatin C antibodies. The cystatin C level was assayed in cerebrospinal fluid samples from 29 patients with brain hemorrhage and 45 control patients with other neurological diseases. Fifteen patients with brain hemorrhage showed low cystatin C levels (less than or equal to 70 ng/ml) in a clinical setting in which the positive and negative findings were compatible with a diagnosis of cerebral amyloid angiopathy. Immunohistological examination of brain tissue obtained by biopsy from two of the 15 patients confirmed the diagnosis of cerebral amyloid angiopathy and identified the deposition of cystatin C and beta-protein. This enzyme-linked immunosorbent assay is simple to perform and may be useful for investigating patients suspected of having cerebral amyloid angiopathy with brain hemorrhage and the deposition of cystatin C.
Pain on intradermal injection with lignocaine. The effect of concentration. Twenty ASA 1 volunteers were each injected intradermally with four solutions containing 0.2 ml of 0.5%, 1%, and 2% lignocaine and 0.9% saline to determine whether the pain experienced on injection was related to the concentration of local anaesthetic. A 10 cm linear analogue pain scoring system was used, and the solutions were ranked from most painful to least painful. There were no differences between the different concentrations of lignocaine and 0.9% saline in the severity of pain experienced. We conclude that any concentration of lignocaine may be used intradermally before inserting intravenous catheters without affecting the degree of pain experienced by that injection.