shukoor65/lab-rag-model huggingface dataset:
Apnoea, bradycardia, and oxygen saturation in preterm infants. To analyse the effects of apnoea and bradycardia on the oxygen saturation (SaO2) of preterm infants and to make recommendations for apnoea alarm limits, polygraphic recordings were made on 89 occasions of 27 preterm infants; 1029 apnoeic episodes were analysed. Reduction in SaO2 was positively correlated with duration of apnoea, but the scatter of results was such that reductions in SaO2 of up to 40% occurred with apnoeas of less than 10 seconds duration. The median initial SaO2 was significantly lower in those episodes that resulted in bradycardia (92% compared with 95%), and there was also a significantly greater reduction in median SaO2 (9% compared with 5%). This study illustrates the difficulty of setting alarm limits for the detection of apnoea. We suggest that rather than simply detecting apnoea it is more appropriate to monitor heart rate and SaO2 in infants with recurrent apnoea.
Visual field changes following hepatic transplantation in a patient with primary biliary cirrhosis. A case of severe visual field restriction complicating primary biliary cirrhosis is described. The clinical features demonstrated vitamin A deficiency which did not respond to oral supplements of vitamin A. Hepatic transplantation restored the visual fields to near normal.
Aortic sepsis: is there a role for in situ graft reconstruction? Conventional extraanatomic reconstruction for aortic sepsis is associated with a significant risk of operative death, as well as frequent late complications. We evaluated in situ aortic grafting in the treatment of primary or graft-related aortic infection. Eleven selected patients underwent in situ aortic graft reconstruction in the setting of mycotic aneurysm (n = 5), secondarily infected aortic aneurysm (n = 1), primary aortoenteric fistula (n = 1), and secondary aortoenteric fistula (n = 4). All patients survived: follow-up from 10 to 130 months reveals no evidence for graft thrombosis, pseudoaneurysm, new or recurrent aortoenteric fistula, or subsequent aortic operations in any patient. A literature review produced 110 cases of aortic sepsis managed by in situ aortic reconstruction during the last decade. Thirty-two patients (29%) either died in the operative period or suffered a lethal late complication associated with their aortic reconstruction. This mortality rate declined to 21% if patients undergoing incomplete removal of a contaminated graft were excluded, and to 19% with the addition of our 11 patients. Both our experience and that described in the literature suggest that, in properly-selected patients, in situ aortic graft replacement may be a rational treatment option for localized or circumscribed aortic sepsis.
Cardiac tamponade early after thrombolysis for acute myocardial infarction: a rare but not reported hemorrhagic complication. Among 392 consecutive patients admitted for acute myocardial infarction and treated with thrombolytic drugs, 4 patients (1%) developed an early hemorrhagic pericardial effusion (without ventricular wall rupture) evolving within 24 h to cardiogenic shock consequent to cardiac tamponade. They all suffered from a large anterior myocardial infarction treated within 4 h after onset of symptoms with intravenous anisoylated plasminogen streptokinase activator complex (one case), recombinant tissue-type plasminogen activator (rt-PA) (two cases) or streptokinase (one case), anticoagulation with heparin (all cases) and aspirin (three cases). As soon as pericardial effusion was established by echocardiography, emergency percutaneous pericardiocentesis was performed at the bedside 20 +/- 6 h after thrombolytic therapy was started. This corrected immediately the clinical and hemodynamic status of each patient and a catheter was left in the pericardial space for 34 +/- 18 h. Thus, in the presence of unexplained clinical and hemodynamic deterioration occurring during the first 24 h after thrombolytic treatment of a large myocardial infarction, cardiac tamponade should be suspected. Immediate percutaneous pericardiocentesis followed by continuous drainage is a simple and definitive treatment for this complication.
The GTPase superfamily: a conserved switch for diverse cell functions. Proteins that bind and hydrolyse GTP are being discovered at a rapidly increasing rate. Each of these many GTPases acts as a molecular switch whose 'on' and 'off' states are triggered by binding and hydrolysis of GTP. Conserved structure and mechanism in myriad versions of the switch--in bacteria, yeast, flies and vertebrates--suggest that all derive from a single primordial protein, repeatedly modified in the course of evolution to perform a dazzling variety of functions.
Cavernosometry: methodology and reproducibility with and without pharmacological agents in the evaluation of venous impotence. Venous impotence can be evaluated by cavernosometry, although this is a controversial issue. We have evaluated various techniques for cavernosometry: with and without intracavernous papaverine, with different dosages and modalities, with different modes of induction flow and at various intracavernous pressures. A standardised technique was tested and retested in 32 impotent men. If pharmacocavernosometry is accepted as the most reliable test and a maintenance flow less than 20 ml/min indicates optimal venous occlusion, plain cavernosometry gave 6% false positive and 16% false negative results. Pharmacocavernosometry was found to be highly reproducible with regard to maintenance flow for patients thought to have optimal venous occlusion and for those with supposed leakage. The induction flow was of no diagnostic value. After injection of papaverine the maintenance flow became a reproducible parameter for quantifying venous outflow and could be measured with an intracavernous pressure equivalent to systolic blood pressure to minimise cavernous arterial inflow and increase reproducibility.
Immediate postoperative aspirin improves vein graft patency early and late after coronary artery bypass graft surgery. A placebo-controlled, randomized study. BACKGROUND. The efficacy of aspirin for prevention of thrombotic graft occlusion after coronary artery bypass grafting (CABG) depends both on the dosage and time window of administration. Early and late graft patency were therefore assessed in a prospective, double-blind, randomized, placebo-controlled trial of aspirin, 324 mg daily, given within 1 hour of CABG. METHODS AND RESULTS. Angiographic graft patency was determined at 1 week (231 patients) and 1 year (219 patients) after CABG. The early vein graft occlusion rate was 1.6% on aspirin and 6.2% on placebo (p = 0.004), and late graft occlusion rate was 5.8% on continued aspirin and 11.6% on placebo (p = 0.01). New graft occlusion between 1 week and 1 year was less common in patients on aspirin than on placebo (4.3% versus 7.4%, p = 0.013). The protective effect of aspirin against occlusion persisted in most subgroups of graft type, graft flow, diameter of recipient artery, location of grafted artery, and endarterectomy. Mean chest tube blood loss for the first 24 hours was 571 ml for the aspirin group and 563 ml for the placebo group. Red cell transfusion requirements were 902 ml in the aspirin group and 934 ml in the placebo group (p = NS). The reoperation rate was 4.8% in the aspirin group and 1% in the placebo group (p = 0.1). CONCLUSIONS. Immediate postoperative administration of aspirin (324 mg) improves early graft patency and, with continued usage, protects against further occlusion up to 1 year after CABG. Postoperative blood loss was similar in the two groups; however, aspirin was associated with a nonsignificant higher rate of reoperation.
Gonadotropin-secreting pineal teratoma causing precocious puberty. A case of precocious puberty in a 7-year-old boy with a tumor of the pineal region is reported. Human chorionic gonadotropin levels were elevated in the serum and cerebrospinal fluid. Endocrinological evaluation of the hypothalamic-pituitary axis demonstrated a normal prepubertal response. The tumor was resected and proved to be an immature teratoma. Human chorionic gonadotropin levels were markedly elevated in the tumor cyst fluid. Sexual precocity regressed and human chorionic gonadotropin levels in the serum and cerebrospinal fluid fell to normal after surgery, suggesting that the precocious puberty was secondary to ectopic human chorionic gonadotropin production by the pineal teratoma.
Stenoses of vascular anastomoses after hepatic transplantation: treatment with balloon angioplasty. Vascular complications after liver transplantation include occlusion or stenosis at the sites of anastomosis in the hepatic artery, portal vein, and vena cava. From our experience with more than 600 liver transplants, vascular stenoses have been identified in 10 patients and treated by balloon angioplasty in nine. Three patients with hepatic artery stenosis and deteriorating graft function were treated by balloon angioplasty with a coaxial technique. A specially designed catheter facilitated a successful femoral artery approach. Portal vein stenoses in three patients resulted in portal hypertension. These were treated by balloon dilatation via transhepatic catheterization of the portal vein. Stenoses of the suprahepatic caval anastomosis were dilated in three patients with severe lower limb edema. Technical success was achieved in all three cases of hepatic artery stenosis with improvement in graft function. Recurrent stenoses in two patients were successfully treated with repeated dilatations. Portal hypertension resolved in two of three patients after portal venoplasty. Dilatation of a caval stenosis resulted in the resolution of leg edema in all three cases. Repeated dilatation was required in one case. No reduction in the portal venous pressure gradient occurred after venoplasty in one case, and an ultimately fatal caval thrombosis developed in one patient with caval stenosis before venoplasty could be performed. Our experience suggests that balloon angioplasty of arterial and venous stenoses complicating hepatic transplantation carries little risk and is a useful procedure for the treatment of these problems.
The spectrum of vertical gaze palsy following unilateral brainstem stroke. A single unilateral lesion, near the midline, may interrupt the pathways involved in vertical gaze just before and after they decussate, inducing an anatomically unilateral, but functionally bilateral, lesion. We report 11 patients with supranuclear vertical gaze palsies (two with conjugate upgaze palsy, four with combined up- and downgaze palsies, two with monocular elevation palsy, and three with vertical "one-and-a-half" syndrome) due to unilateral midbrain strokes.
Rates of vertebral bone loss before and after liver transplantation in women with primary biliary cirrhosis. Atraumatic fractures caused by osteoporosis may be a serious complication of primary biliary cirrhosis. Mean (+/- S.D.) bone mineral density in the lumbar spine in 210 ambulatory women with primary biliary cirrhosis was 1.02 +/- 0.19 gm/cm2, 7% lower than that in 139 age-matched normal women (after adjustment for age and body weight) (p less than 0.001). Bone mineral density in the lumbar spine was inversely related to a risk score index of liver disease severity (r = -0.29, p less than 0.001). The mean rate of bone loss in 105 of these 210 women was 2%/yr +/- 4%/yr, twice as great as in the 139 normal women (p less than 0.02). In 20 women with primary biliary cirrhosis followed up after orthotopic liver transplantation, bone mineral density in the lumbar spine decreased at 3 mo (p less than 0.01), and this decrease may have resulted in atraumatic fractures in 13 of them. Bone mineral density in the lumbar spine then increased (p less than 0.01) so that by 12 mo the median bone mineral density in the lumbar spine was similar to that before transplantation and by 24 mo it was 5% above it. Therefore we conclude that the progressive bone loss observed in primary biliary cirrhosis (which is further accentuated immediately after transplantation) may be halted, and the bone mass may be restored toward normal within 2 to 3 yr after orthotopic liver transplantation.
Primary anetoderma associated with a wide spectrum of autoimmune abnormalities. Although the underlying pathologic mechanisms of primary anetoderma have not yet been identified, data suggest the participation of an immunologic mechanism in some cases. In a woman with clinical and histopathologic features of primary anetoderma (Jadassohn-Pellizzari type) of 30 years' duration, laboratory investigation disclosed positive antinuclear factor, hypocomplementemia, hypergammaglobulinemia, granular deposits of immunoreactants along the dermoepidermal junction, and fibrillar deposits in the papillary dermis. In addition, she was found to have autoimmune hemolysis and circulating lupus anticoagulant associated with recurrent deep-vein thrombosis and a history of Graves' disease (starting 5 years after onset of primary anetoderma). To our knowledge, none of the latter three autoimmune conditions has been previously associated with primary anetoderma.
Biological significance of tissue plasminogen activator content in brain tumors. Fresh brain-tumor samples were obtained at operation and analyzed for their content of tissue type plasminogen activator (tPA) using an activity assay (gel chromatography zymogram) and an enzyme-linked immunospecific assay. The specimens were taken from 23 glioblastomas, 35 metastatic tumors, 42 meningiomas, 16 low-grade gliomas, and seven acoustic neurinomas; seven specimens were from normal brain. A strong correlation was found between the results of the two assays (r = 0.77, p less than 0.0001). There was a threefold difference in the tPA content of the benign tumors as compared to malignant tumors (p = 0.0006), the latter having less tPA. Histologically benign meningiomas contained higher tPA than malignant meningiomas (p = 0.01); however, the difference between low-grade gliomas and high-grade gliomas was less evident. Overall regression analysis data have shown an inverse relationship between the tissue content in tPA and the presence and degree of tumor necrosis and peritumoral brain edema (p = 0.004 and p = 0.0004, respectively). This finding was most consistent in the glioblastoma group where the correlation coefficient values were r = 0.53 and r = -0.55, respectively. There was no significant correlation between the tissue tPA content and the age and sex, steroid use, or plasma tPA of the patients or the duration of symptoms. In summary, this is the first demonstration of tPA in a large series of human brain tumors and in normal brain. The differences observed have clear biological significance and, although the source of tPA in tumor tissue is still unknown, a relative reduction in tPA in tumor tissue may play an integral role in the development of tissue necrosis and tissue edema. The lack of tPA in tumor necrosis was not due to tissue destruction and cell death since urokinase was readily detectable in that tissue.
Autonomic nervous system dysregulation in human hypertension. An increased sympathetic drive combined with decreased parasympathetic inhibition is found in patients with borderline hypertension, who characteristically have rapid heart rates, high cardiac output and relatively normal vascular resistance (hyperkinetic state). In established hypertension, cardiac output is normal, vascular resistance is elevated and signs of increased sympathetic drive are absent. Apparently hemodynamics and sympathetic drive change during hypertension. The mechanism of the hemodynamic transition in the course of hypertension is well understood. Cardiac output returns from elevated to normal values as beta-adrenergic receptors down-regulate and stroke volume decreases (due to decreased cardiac compliance). The high blood pressure induces vascular hypertrophy, which in turn leads to increased vascular resistance. The mechanism of the change of sympathetic tone from elevated in borderline hypertension to apparently normal in established hypertension can best be explained within the conceptual framework of the "blood-pressure-seeking" properties of the brain. In hypertension, the central nervous system seeks to maintain systemic blood pressure at the higher level. As hypertension advances and vascular hypertrophy develops, arterioles become hyperresponsive to vasoconstriction. At this point, less sympathetic drive is needed to maintain pressure-elevating vasoconstriction, and the central sympathetic drive is down-regulated. The etiology of increased sympathetic drive in hypertension remains unresolved. Subjects with increased sympathetic drive are also usually overweight and have elevated levels of insulin, cholesterol and triglycerides, as well as decreased high-density lipoproteins. Future research must focus on the link between coronary risk factors and sympathetic overactivity in hypertension.
Miller-Dieker syndrome with ring chromosome 17. A girl presented at 6 weeks of age with failure to thrive and arching of the back. She had various dysmorphic features, hepatosplenomegaly, and developmental delay. The electroencephalogram and cranial ultrasound were abnormal, and a computed tomogram showed lissencephaly and apparent agenesis of the corpus callosum. Because of frequent aspiration she became oxygen dependent. She later developed intractable convulsions and died at the age of 9 months.
The arrhythmogenicity of theophylline. A multivariate analysis of clinical determinants. OBJECTIVE: to determine the relation of serum theophylline concentrations (STC) to the occurrence of cardiac arrhythmias in a population of hospitalized patients. STUDY DESIGN: A cross-sectional study of 100 patients receiving theophylline who had electrocardiograms at the time STC had been obtained. Categorization was based on STC without knowledge of clinical status: group 1 (25) had STC less than 2.5 mg/L; group 2 (25), STC greater than or equal to 2.5 less than 10 (6.2 +/- 0.4) mg/L; group 3 (25), STC greater than or equal to 10 less than or equal to 20 (15.8 +/- 0.4) mg/L; and group 4 (25), STC greater than 20 (27.8 +/- 1.1) mg/L. SETTING: A university-affiliated teaching hospital. RESULTS: Two-thirds of the patients were receiving theophylline in an oral form, with a similar distribution found in all groups. Groups were not different with respect to age, clinical diagnoses, electrocardiographic patterns, arterial pH or gases, serum calcium, or treatment with beta-agonists. Although fewer patients in group 1 were receiving steroids than those in the other groups, and serum potassium was lower in group 3 than in group 1 (4.0 +/- 0.6 vs 4.5 +/- 0.5 mEq/L, p less than 0.05), on multivariate analysis, serum potassium was not an independent predictor of arrhythmia, and treatment with steroids or digoxin was, at most, only weakly associated with the presence of arrhythmia. Heart rate was directly related to STC (r = 0.64, p less than 0.01), and STC was the strongest independent predictor of arrhythmia in this population. Although only 20 percent of patients in group 1 or 2 had arrhythmias, 48 percent of group 3 (p less than 0.05) and 56 percent of group 4 (p less than 0.05) had this finding. Moreover, the odds ratio of group 3 having an arrhythmia compared with group 1 was 3.7, 1.5 to 11.7, p less than 0.01. Multifocal atrial tachycardia was found in 8 percent of the patients in group 3 and 16 percent in group 4 but in none of the patients in groups 1 or 2. Two patients with multifocal atrial tachycardia died suddenly within 24 hours of having their STC measurement; none had concomitant ventricular ectopy. CONCLUSION: Theophylline causes tachycardia and serious arrhythmias even at STC considered to be therapeutic. Multifocal atrial tachycardia, an arrhythmia associated with use of this drug, may herald sudden cardiac death.
Fourth branchial pouch sinus: diagnosis and treatment. The fourth branchial pouch sinus (FBPS) is a rare translaryngeal anomaly with diverse manifestations, including neonatal stridor and recurrent deep neck infection. Review of the world literature reveals 23 reports of sinuses consistent with fourth pouch origin. We present two additional cases, including the only example of a right-sided FBPS. Retrograde excision, beginning at the piriform apex, ensures complete removal of the tract and protection of the recurrent nerve. The posterior border of the thyroid ala must be resected or retracted for adequate exposure. Failure to remove the translaryngeal portion of the tract almost guarantees recurrence.
Suprascapular nerve entrapment. A series of 27 cases. Suprascapular nerve entrapment is an acquired neuropathy secondary to compression of the nerve in the bony suprascapular notch. A series of 27 cases, the largest reported to date, is presented and examined as to the best and most appropriate method of diagnosis and treatment. The entity is described in detail as to its origin, anatomy, and pathophysiology.
Acute effects of ethanol on cultured myocardial cells: an ultrastructural study. Myocardial cells in monolayer culture were examined ultrastructurally at various times (5 min-24 hr) after addition of ethanol (12.5-500 mM). At 5 min, all concentrations of ethanol induced mitochondrial fusion and a remarkable increase in glycogen granules, and the mitochondrial outer membrane seemed more fragile. These initial ultrastructural changes then recovered with time. Glycogen granules were decreased, then returned to normal more rapidly as the ethanol concentration was increased. Mitochondrial fusion and fragile appearance of the outer membrane were hardly seen at 1 hr in the presence of 12.5 or 50 mM ethanol, but were still evident with higher ethanol concentrations (200 and 500 mM), though less frequently than at 5 and 30 min. Furthermore, 'giant mitochondria' (with at least a five-fold increase in sectional area) appeared in the presence of 200 and 500 mM ethanol with increasing time of exposure. These results are discussed in relation to the direct effects of ethanol.
Kikuchi-Fujimoto syndrome during pregnancy. Necrotizing lymphadenitis of the Kikuchi-Fujimoto type developed in our patient during her first trimester of pregnancy, but she carried the infant to full term with no apparent adverse effect. Two subsequent pregnancies were not associated with reactivation of the disorder, nor with any recognizable adverse effect on the fetuses. A pregnancy should not be terminated because of Kikuchi-Fujimoto necrotizing lymphadenitis when it develops during the first trimester of pregnancy.
Diagnostic problems in tissues previously sampled by fine-needle aspiration. Unusual tissue changes in needle tracts after fine-needle aspiration were studied in two specimens. One specimen, a 3.0 x 2.5 cm mesenteric nodule, was found six days after a nondiagnostic transabdominal fine-needle aspiration of a retroperitoneal mass. At frozen-section examination, the nodule had proliferating spindle-shaped cells interspersed with adipocytes that raised the possibility of well-differentiated liposarcoma. On permanent sections, however, there was fat necrosis and reactive spindle-shaped cells that immunohistochemically were consistent with myofibroblasts. In the second case, a needle tract was noted in breast tissue on which a biopsy was performed two days after a cytologic diagnosis of carcinoma. The 0.4-mm-wide tract contained neutrophils, foamy histiocytes, and clumps of intact, atypical epithelial cells without a desmoplastic or elastotic component. Aside from these epithelial cells, nothing in the biopsy specimen suggested invasive carcinoma. The cells were identical to those from a comedocarcinoma present in the biopsy and mastectomy specimens. These two cases provide examples of pitfalls that may arise during the examination of biopsy specimens obtained after fine-needle aspiration.