shukoor65/lab-rag-model huggingface dataset:
Treating insulin resistance in hypertension with metformin reduces both blood pressure and metabolic risk factors. Insulin resistance and hyperinsulinaemia may play an important role in both the development of hypertension and its accompanying metabolic aberrations. In order to investigate this possibility, nine non-obese, non-diabetic, non-smoking, middle-aged men with untreated hypertension were treated with metformin 850 mg b.i.d. for 6 weeks as a pilot study and within-patient comparison. Metformin decreased total and LDL-cholesterol (P less than 0.01), triglyceride (P less than 0.01), fasting plasma insulin (P less than 0.01) and C-peptide levels (P less than 0.02). Glucose disposal, an indicator of insulin action measured by means of the euglycaemic clamp technique, increased (P less than 0.001). Tissue plasminogen activator (t-PA) activity increased (P less than 0.02), and t-PA antigen decreased (P less than 0.01), whereas plasminogen activator inhibitor (PAI-1) and fibrinogen were unaffected by metformin treatment. Body weight remained unchanged. Withdrawal of metformin was associated with the return of both blood pressure and metabolism towards the initial levels. In conclusion, metformin treatment increased insulin action, lowered blood pressure, improved the metabolic risk factor profile and tended to increase the fibrinolytic activity in these mildly hypertensive subjects. These results support the view that insulin resistance plays a role in hypertension, and may open up a new field for the alleviation of abnormalities associated with cardiovascular disease.
Generalized cortical dysplasia. Clinical and pathologic aspects. Three children with profound mental retardation and intractable seizures died at ages 10 months, 3 years, and 7 years, respectively. Complete examination of their brains showed generalized cortical dysplasia, without any major malformation of the external gyral pattern. The neuropathologic features of cortical dysplasia include abnormally thickened cortex with indistinct demarcation of the gray-white matter junction. In many areas, the cortex contained increased numbers of large neurons with disordered cortical lamination. Heterotopic neurons were scattered throughout the white matter with decreased myelination of the underlying white matter. To our knowledge, these cases represent the first fully detailed neuropathologic study of diffuse cortical dysplasia--a newly recognized entity of abnormal neuronal migration.
Alcohol induction of ferritin expression in a human hepatoblastoma cell line (HEP G2). Hyperferritinemia, an unclear mechanism, is frequently observed in chronic alcoholics. The aim of this work was to study the effect of alcohol on ferritin expression in a human hepatoblastoma cell line, HepG2. This cell line proved to be sensitive to alcohol, since alcohol increased gamma-GT activity both in cells and media. The most striking result was the increase of ferritin in cells and media by alcohol. Moreover, this effect was specific, since it contrasted with a decrease in total protein synthesis and secretion, a decrease in transferrin excretion and a lack of effect on orosomucoid. In our model, alcohol was able to induce, in a specific manner, ferritin expression.
Comparison of the findings on preoperative dipyridamole perfusion scintigraphy and intraoperative transesophageal echocardiography: implications regarding the identification of myocardium at ischemic risk. The evidence of myocardium at potential ischemic risk on preoperative dipyridamole perfusion scintigraphy was compared with that of manifest ischemia on intraoperative transesophageal echocardiography in 26 patients at high risk of a coronary event undergoing noncardiac surgery. The clinical outcome was also assessed. Induced intraoperative wall motion abnormalities were more common in patients and myocardial segments with, than in those without, a preoperative reversible perfusion defect (both p less than 0.05). Conversely, a preoperative reversible perfusion defect was more common in patients and segments with, than in those without, a new intraoperative wall motion abnormality (both p less than 0.05). Six patients, five with a reversible scintigraphic defect but only three with a new wall motion abnormality, had a hard perioperative ischemic event. Events occurred more often among patients with, than in those without, a reversible perioperative scintigraphic defect (5 [33%] of 15 vs. 1 [9%] of 11) but this difference did not reach significance (p = 0.14), probably owing to the sample size. Intraoperative wall motion abnormalities were all reversible and did not differentiate between risk groups; these findings were possibly influenced by treatment. These preliminary data support the known relation between reversible scintigraphic defects and perioperative events and identify another manifestation of ischemic risk in the relation between reversible scintigraphic defects and induced intraoperative wall motion abnormalities. The value of intraoperative echocardiography in identifying ischemia and guiding therapy in patients with a reversible scintigraphic abnormality should be further assessed.
Recognition, management, and prevention of Clostridium septicum abscess in immunosuppressed patients. Spontaneous gas gangrene due to Clostridium septicum is a rapidly progressing disease that usually ends in fatal toxemia. We report three cases of asymptomatic C septicum abscesses to document the clinical course of this entity and to establish guidelines for its prevention and treatment. In contrast to previously reported data, C septicum infections can produce abscesses in solid organs, the retroperitoneum, and the extremities. These lesions often occur in patients with cancer, producing liver abscesses without gas formation that may be misinterpreted as metastatic carcinoma. Symptoms may be minimal or nonspecific before fulminant toxemia. Asymptomatic bacteremia should prompt a search for unsuspected cancer and an abscess. Computed tomography is the diagnostic modality of choice. The treatment consists of surgical debridement of necrotic tissue in concert with an appropriate course of antibiotics. We have found recurrences after adequate debridement and short-term antibiotic therapy, suggesting that prolonged and even lifelong prophylactic oral penicillin G potassium may be necessary to prevent further recurrences.
Time course of hypoxic pulmonary vasoconstriction after endotoxin infusion in unanesthetized sheep. Endotoxin [lipopolysaccharide (LPS)] has been reported to reduce hypoxic pulmonary vasoconstriction and thus increases venous admixture. The time course of this failure of pulmonary blood flow regulation was investigated in six chronically instrumented unanesthetized sheep after infusion of Escherichia coli LPS (1 microgram/kg). The change in left pulmonary arterial blood flow (LPBF, ultrasonic transit time) in response to unilateral lung hypoxia (10 min of N2 alternately to the left and right lungs) was compared before and at various time intervals after the administration of LPS. During baseline conditions, LPBF was 33% of total cardiac output and decreased to 15% when the left lung was ventilated with a hypoxic gas mixture. One hour after endotoxin infusion, LPBF remained at 33% of total cardiac output yet only decreased to 28% during the hypoxic challenge. The response to one-lung hypoxia was still significantly depressed 10 h post-LPS administration. It is concluded that hypoxic pulmonary vasoconstriction is almost completely abolished for a prolonged time period after a small dose of LPS.
Changes in upper airway resistance during progressive normocapnic hypoxia in normal men. The effects of normocapnic progressive hypoxia on nasal and pharyngeal resistances were evaluated in nine normal men. To calculate resistances, upper airway pressures were measured with two low-bias flow catheters; one was placed at the tip of the epiglottis and the other in the posterior nasopharynx, and we measured flow with a Fleish no. 3 pneumotachograph connected to a tightly fitting mask. Both resistances were obtained during a baseline period and during progressive normocapnic hypoxia achieved by a rebreathing method. We collected the breath-by-breath values of upper airway resistances, minute ventilation, O2 and CO2 fractions, arterial O2 saturation (SaO2), and changes in functional residual capacity (inductance vest). The central respiratory drive was evaluated by the mouth occlusion pressure 0.1 s after the onset of inspiration (P0.1), and breath-by-breath P0.1 values were estimated by intrapolation from the linear relationship between P0.1 and SaO2. In each subject both resistances decreased during the hypoxic test. The slope of the decrease in resistance with decreasing SaO2 (%baseline/%SaO2) was steeper for pharyngeal resistance than for nasal resistance [2.67 +/- 0.29 and 1.61 +/- 0.25 (SE), respectively; P less than 0.05]. The slope of the decrease in resistance with increasing P0.1 (%baseline/cmH2O) was -0.24 +/- 0.05 for nasal resistance and -0.39 +/- 0.07 for pharyngeal resistance (P less than 0.05). Functional residual capacity progressively increased during the test, but the decrease in resistance was greater than expected from an isolated increase in lung volume. We conclude that nasal and pharyngeal resistances decrease during progressive normocapnic hypoxia.
Long-term angiographic follow-up after angioplasty of venous coronary bypass grafts. From April 1981 to June 1987, 57 patients underwent venous coronary bypass graft percutaneous angioplasty and had a minimal follow-up of 18 months. The procedure was elective for 28 patients, urgent for 19, and was considered as an emergency for 10. A total of 64 grafts were dilated that had been bypassed 58 +/- 48 months previously (range 2 to 184 months); lesions were located on the aortic anastomosis in 12 grafts, on the body in 38, and on the coronary anastomosis in 14. Technical success was 95.3% (61 of 64) per lesion; clinical success was 84.4% (54 of 64) per lesion and 82.5% (47 of 57) per patient. Thrombotic complications with images of a lacunar defect occurred in 11 grafts (17.2%). Predictive factors for these complications were: age of grafts 38.5% for greater than 60 month grafts versus 2.6% for less than 60 month grafts (p less than 0.01); site of lesion, body lesion 28.9% versus anastomosis none (p less than 0.01); type of lesion, concentric and short 6% versus other 29% (p less than 0.05); and recent fibrinolysis in 66% versus 10.6% (p less than 0.05). Long-term follow-up is available in the 47 successful patients and the three limited non-Q wave myocardial infarction patients. Two patients died at 13 and 17 months. Long-term angiographic follow-up is available in 45 of 48 patients or 94%. At the end of the study, 35 of 57 (61.4%) venous bypass grafts in 32 patients (64%) were patent after one or more percutaneous transluminal angioplasties.
Differences in "primary response" gene expression in renal compensatory hypertrophy and hyperplasia. The induction of a family of primary response genes (ie, genes whose transcription is not dependent on new protein synthesis) occurs within minutes after stimulation of quiescent 3T3 cells by phorbol esters and growth factors. A similar pattern of gene expression is seen in PC-12 pheochromocytoma cells induced to differentiate by nerve growth factor (NGF), suggesting that a common set of activating signals occur in different forms of cell growth. To determine whether the same "activation" process occurs in renal hypertrophy, we measured mRNA levels in mice subjected to uninephrectomy (UNX) or sham operation. Regenerative renal hyperplasia was induced by intraperitoneal folic acid (FA) injection with vehicle as control. Northern blots showed induction of these genes by FA with elevated mRNA levels persisting for up to 24 to 48 hours. UNX and sham operation demonstrated a slight and transient elevation of mRNA levels, with a prompt return to basal levels by 60 minutes.
Long-term psychologic implications of congenital heart disease: a 25-year follow-up. Patients with various types of congenital heart disease were contacted 25 years after their original examination at the Mayo Clinic. In addition to providing their current health status, level of education achieved, and current occupation, they were asked to complete a detailed standardized questionnaire to assess their degree of psychologic stress. Of the original 463 patients, 168 completed and returned the psychologic questionnaires. These patients had evidence of psychologic stress in excess of that expected on the basis of normative data. Furthermore, the degree of stress was unrelated to the clinical severity of the original cardiac defect. In addition, the psychologic stress occurred despite "success" as defined by educational achievement and occupational level. One can speculate that as children these patients were exposed to environmental stresses that may well have been colored by parental attitudes and perceptions.
Spinal epidural hematoma causing cord compression after tissue plasminogen activator and heparin therapy. Bleeding is the most serious complication of thrombolytic therapy and limits its usefulness. We have reported a case of epidural hematoma, a rare occurrence after combined therapy with tissue plasminogen activator (TPA) and heparin. We emphasize that in patients treated with thrombolytic agents, any trauma may increase the risk of bleeding. The sudden onset of back pain and neurologic deficits should alert the clinician to the possibility of spinal hematoma with cord compression.
Cerebral edema causing death in children with maple syrup urine disease. Four children with the classic form of maple syrup urine disease (MSUD) died of cerebral edema during an intercurrent infection that caused severe dehydration and acidosis. The diagnosis of MSUD had been established during the neonatal period in all four patients, on day 1 of life in three of them. All were in satisfactory control before the intercurrent illness. Two patients underwent peritoneal dialysis. Signs of brain-stem compression occurred after treatment, when biochemical abnormalities were improving. Computed tomography of the head, which was done in two patients, revealed cerebral edema; one of these patients also had subarachnoid hemorrhage. Autopsy in one case revealed cerebral edema with herniation. Our experience documents that cerebral edema may occur in the older child with MSUD as well as in the neonate. The pathogenesis of cerebral edema in MSUD remains unclear. Early treatment of dehydration and acidosis may prevent the catastrophic consequences that we have observed.
The association of frequent headaches with personality and life events. The associations between personality traits, life events and frequent headaches were studied in a sample of 5766 adult subjects between 20 and 65 years of age from the general population. Subjects with at least weekly headaches had more life events and higher inadequacy, social inadequacy, rigidity and injuredness than subjects with less frequent headaches. These relationships were not observed in subjects of 50 years of age and older, with the exception of the association with inadequacy. From the traits measured, inadequacy had the highest odds ratios for frequent headaches and showed a modest interaction with the presence of a life event. These findings are in agreement with Sarason's interactional model.
Inflammation at the neuromuscular junction in myasthenia gravis. To better define the pathogenic mechanisms in the antibody-mediated autoimmune disease myasthenia gravis (MG), we analyzed the morphology and electrophysiology of the neuromuscular junction in anconeus muscle biopsy specimens from eight patients with MG and seven control subjects. There were inflammatory cells at the neuromuscular junction in seven of the eight biopsies from MG patients. The endplate index (length of the postsynaptic membrane divided by the length of the apposed presynaptic membrane) was abnormally reduced in all the MG patients, and fiber type grouping, suggestive of reinnervation, was present in six of the eight MG patients. Intracellular recording revealed diminished amplitude of miniature endplate potentials and miniature endplate currents in the MG patients compared with the controls. The time constant of decay of miniature endplate currents did not differ from that of controls, suggesting no change in mean channel open time of the acetylcholine receptor. The endplate receptor sensitivity to iontophoretically applied acetylcholine was also decreased in MG patients compared with controls. The quantal content of neurally evoked endplate potentials was reduced in six of the eight MG patients, demonstrating abnormal presynaptic function as well. The presence of inflammatory cells at the neuromuscular junctions of limb muscles in MG reconciles an apparent disparity between the animal model of MG, experimental autoimmune myasthenia gravis, and the human disease. This study also demonstrates a frequent presynaptic component to the abnormal neuromuscular transmission in MG.
On lowering lipids in the post-infarction patient. In patients with coronary heart disease (CHD) elevated serum cholesterol levels, like other classical risk factors, remain predictive of further coronary events. The excess risk attributable to raised cholesterol levels is considerable, and greater than that in subjects without CHD. A recent meta-analysis of all eight qualifying trials of secondary prevention of CHD by cholesterol lowering is reviewed. There were significant reductions in recurrent non-fatal and fatal CHD, with a downward trend in total mortality. Mechanisms underlying the relationship between cholesterol lowering and secondary prevention are reviewed. The implication of this analysis of trials for clinical practice is that hypercholesterolaemia should be sought and effectively treated in patients with CHD, unless contraindications are present.
Glutathione peroxidase deficiency and childhood seizures. 4 children with intractable seizures, repeated infections, and intolerance to anticonvulsants had evidence of glutathione peroxidase deficiency. 2 had low intracellular enzyme activity but normal blood selenium and high plasma glutathione peroxidase concentrations. The other 2 had low intracellular glutathione peroxidase activity with low circulating glutathione peroxidase and selenium concentrations. The clinical state of the children improved after discontinuation of anticonvulsant medication and selenium substitution.
Polysialic acid of the neural cell adhesion molecule distinguishes small cell lung carcinoma from carcinoids. The neural cell adhesion molecule (NCAM) exists in various types of neuroendocrine cells and their tumors. A typical feature of NCAM is polysialic acid, of which the chain length is developmentally regulated. The authors have performed a comparative immunohistochemical study on small cell lung carcinomas and bronchial as well as gastrointestinal carcinoids with the monoclonal antibody (MAb) 735 reactive with the long-chain form of polysialic acid. The small cell lung carcinomas, irrespective of their histological type, were positive for polysialic acid. Metastatic tumor cell complexes also exhibited immunostaining. The tumor cell-surface-associated immunostaining for polysialic acid was sensitive to endoneuraminidase. The mature and atypical bronchial and gastrointestinal carcinoids were not immunoreactive for polysialic acid. Cytoplasmic staining in groups of cells of carcinoids (2 of 28 cases) was due to nonspecific antibody binding, which could be prevented by increased ion strength. These data indicate that neuroendocrine tumors of the lung can be distinguished by their content of highly sialylated NCAM.
Malignant tumors of the eye in geriatric patients. The ocular tissues can be the site of a number of malignant tumors in adults and geriatric patients. In addition to posing a threat to the patient's life, these tumors can cause severe visual loss or blindness. Therefore, the primary care clinician should be capable of prompt diagnosis of the various malignant ocular tumors and be prepared to refer the patient for appropriate management. This article provides a photographic guide to the most common primary and secondary malignancies that can affect the eyelid, conjunctiva, intraocular structures, and orbit in the geriatric patient.
Restenosis after coronary angioplasty: a multivariate statistical model to relate lesion and procedure variables to restenosis. The M-HEART Investigators. The Multi-Hospital Eastern Atlantic Restenosis Trial group obtained follow-up angiography in 510 patients with 598 successfully dilated coronary lesions who were enrolled in a controlled trial of the effects of a single dose of 1 g of methylprednisolone on restenosis after coronary angioplasty. The overall restenosis rate was 39.6%. The strongest univariate relations to the restenosis rate were found for lesion location (saphenous vein graft, 68%; left anterior descending artery, 45%; left circumflex artery and right coronary artery, 32%; p = 0.002); lesion length (less than or equal to 4.6 mm, 33%; greater than 4.6 mm, 45%; p = 0.001); percent stenosis before angioplasty (less than or equal to 73%, 25%; greater than 73%, 43%; p = 0.005), percent stenosis after angioplasty (less than or equal to 21%, 33%; greater than 21%, 46%; p = 0.017) and arterial diameter (less than 2.9 mm, 44%; greater than or equal to 2.9 mm, 34%; p = 0.036). Two multivariate models to predict restenosis probability were developed with use of stepwise logistic regression. The preprocedural model, which included only variables whose values were known before angioplasty, entered lesion length, vein graft location, left anterior descending artery location, percent stenosis before angioplasty, eccentric lesion and arterial diameter. The postprocedural model, which also included variables whose values were known after angioplasty was performed, was similar to the preangioplasty model except that it also entered postangioplasty percent stenosis and "optimal" balloon sizing but did not enter eccentric lesion. These data indicate that the probability of restenosis after angioplasty is determined predominantly by the characteristics of the lesion being dilated. They are consistent with the known intimal proliferative mechanism of restenosis, offer a means of identifying lesions at unusually high or low risk of restenosis, and of predicting the likelihood that a particular lesion will restenose after angioplasty and provide a rationale for stratification by restenosis probability in the design of future studies of restenosis.
Prenatal diagnosis of fetal left ventricular aneurysm: a case report and review. Fetal echocardiography in a 30-year-old black woman, gravida 4, para 3, demonstrated left ventricular aneurysm. This was confirmed by color flow pulsed Doppler techniques. After delivery, neonatal echocardiography and magnetic resonance imaging further confirmed the diagnosis. The infant was followed closely and underwent surgical correction at 8.5 months of age. Before surgery, cardiac catheterization demonstrated normal hemodynamic function. A review of the literature revealed a paucity of information. Issues of prenatal diagnosis, antenatal surveillance, method of delivery, and neonatal follow-up are not well defined in either the obstetric or pediatric cardiology literature. A rationale for our approach to this complex problem is presented.