123rc/medical_text huggingface dataset:
Alpha 1-acid glycoprotein and the binding of lidocaine in children with congenital heart disease. The purpose of this study was to evaluate the effect of congenital heart disease (CHD) on the serum concentrations of alpha 1-acid glycoprotein (alpha 1-AGP) and the serum binding of lidocaine. Thirteen children with acyanotic CHD and 12 children with cyanotic CHD were studied and compared with 28 children without heart disease (control). The mean (+/- SD) serum concentration of alpha 1-AGP, as determined by radial immunodiffusion, did not differ significantly among the three groups. Five minutes after administration of 1.5 mg.kg-1 intravenous lidocaine, the free fraction of lidocaine correlated inversely and linearly with the serum concentration of alpha 1-AGP in children with acyanotic CHD (r2 = 0.74; P less than 0.001) cyanotic CHD (r2 = 0.57; P less than 0.005), and control (r2 = 0.63; P less than 0.001). The slopes and intercepts of the linear regressions did not differ significantly among the three groups. We conclude that the serum concentration of alpha 1-AGP in children with CHD does not differ quantitatively or qualitatively from that in children without CHD.
Spontaneous alterations in coronary blood flow velocity before and after coronary angioplasty in patients with severe angina. Cyclic coronary artery flow variations with a spontaneous decline in coronary blood flow to very low levels have been documented in stenosed canine coronary arteries with endothelial injury. These flow variations are associated with transient platelet aggregation and dislodgment and the release of selected mediators, including thromboxane A2 and serotonin. However, cyclic or spontaneous flow variations have not been demonstrated in stenosed coronary arteries in humans. In this study, the hypothesis was tested that spontaneous coronary blood flow velocity variations occur in some patients with stenosed coronary arteries before or after coronary artery angioplasty. Thus, 13 patients with severe and limiting angina underwent intracoronary pulsed Doppler velocimetry of their dilated artery immediately before and after percutaneous transluminal coronary angioplasty, whereas 9 control patients underwent velocimetry of an angiographically normal coronary artery. A 3F catheter with a 20 MHz Doppler crystal was positioned to achieve a maximal stable signal, and the flow velocity signal was recorded continuously for 20 min. Spontaneous flow velocity variations (greater than or equal to 38% change in Doppler frequency shift with wide morphologic changes) were present in 3 of the 13 patients tested. Spontaneous flow velocity variations occurred before angioplasty in one patient, after angioplasty in another and both before and after angioplasty in a third. In addition, 2 of the 13 patients, 1 with spontaneous coronary artery flow velocity variations before angioplasty, had frank vasospasm in an adjacent area just distal to the area of coronary dilation immediately after balloon inflation. These data establish that spontaneous coronary artery flow velocity variations occur in some patients with severe and limiting angina before and after coronary angioplasty. These variations may be related to platelet aggregation or coronary vasoconstriction, or both, at sites of endothelial injury resulting from plaque fissuring or ulceration and endothelial and medial injury occurring during coronary angioplasty.
Nitrite from inflammatory cells--a cancer risk factor in ulcerative colitis? Elevated levels of luminal nitrite and a lowered luminal pH were found in 77 percent of patients with acute ulcerative colitis. No luminal nitrite was found in healthy control subjects. Nitrites are a secretory product of activated macrophages and neutrophils of the lamina propria, whereas the lowered luminal pH is due to diminished bicarbonate formation by impaired colonocytes. A hypothesis is put forward that nitrites, lowered pH, and bacterial amines are conducive to formation of carcinogenic n-nitroso compounds, which reflect a cancer risk in patients with ulcerative colitis dependent on the type and extent of inflammatory cell activation as well as metabolic impairment of colonic epithelial cells.
A randomized comparison of manipulation of the fractured nose under local and general anaesthesia. Reduction of simple nasal fractures may be performed under local or general anaesthesia: the latter is by far the most popular method in Britain, though why is hard to define. We have attempted to compare the 2 approaches by means of a randomized, prospective trial. Fifty consecutive, adult patients with radiologically proved fractures of the nasal bones were randomized to a local or general anaesthesia group and underwent manipulation with Asch's and Walsham's forceps between 7 and 15 days post-injury. Analysis of results at 4 h and 8 weeks post-operatively showed no significant benefit conferred by fracture reduction under general anaesthesia as opposed to local anaesthesia with respect to post-operative airway patency or cosmesis. It is suggested that significant benefits can be obtained in terms of patient convenience and cost effectiveness if nasal fractures are reduced under local anaesthesia as an outpatient procedure.
Recurrent cyanotic episodes with severe arterial hypoxaemia and intrapulmonary shunting: a mechanism for sudden death The pathophysiology of recurrent cyanotic episodes has been investigated in 51 infants and children. Episodes began at a median age of 7 weeks (range 1 day to 22 months, 39 at less than 4 months). They were characterised by the rapidity of onset and progression of severe hypoxaemia with early loss of consciousness from cerebral hypoxia. The most common precipitating factor was a sudden naturally occurring stimulus from pain, fear, or anger. In uncontrolled trials, cyanotic episodes were reduced in frequency and severity by tetrabenazine (n = 15) and additional inspired oxygen (n = 10). Eight patients died suddenly and unexpectedly (four during cyanotic episodes). Twenty eight patients underwent physiological studies during cyanotic episodes. There was no evidence of seizure activity at the onset and although prolonged absence of inspiratory effort with continued expiratory efforts was common, breathing sometimes continued. Episodes were not caused by upper airway obstruction and sometimes occurred during positive airway pressure ventilation. The rapidity of fall in arterial oxygen pressure and continued breathing suggested a right to left shunt of sudden onset. The results of contrast echocardiography and lung imaging studies confirmed that this was occurring within the lungs. These cyanotic episodes included both intrapulmonary shunting and prolonged expiratory apnoea. They are best explained by interactions between central sympathetic activity, brainstem control of respiration and vasomotor activity, reflexes arising from around and within the respiratory tract, and the matching of ventilation to perfusion in the lungs. They are a cause of sudden unexpected death in infancy and early childhood.
Immunohistochemical detection of abnormal cell proliferation in colonic mucosa of subjects with polyps. Previous studies have shown the presence of increased proliferation in the large bowel epithelium of those at high risk of developing colon cancer. An in vitro technique for labelling large bowel mucosa with the thymidine analogue bromodeoxyuridine (Brdu) was therefore developed and its ability to distinguish differences in mucosal proliferation between subjects with colorectal adenomas and normal controls was assessed. Sigmoid biopsy specimens from 15 subjects with polyps and 15 age and sex matched controls were labelled and the incorporated Brdu visualised with an immunohistochemical technique. Mean labelling index (LI) was significantly higher in those with polyps than in controls. Differences in the pattern of labelling in colonic crypts were compared by the generation of cumulative labelling distributions. Analysis showed a significant expansion of the proliferative compartment in the colon crypts of those with polyps. It is concluded that in vitro labelling with Brdu provides a useful method for the assessment of mucosal proliferation in subjects at high risk of developing colon cancer.
The placebo effect in heart failure. Many patients who are enrolled in controlled clinical trials of new drugs for the treatment of heart failure show favorable hemodynamic and clinical responses to placebo therapy. This "placebo effect" results from both the creation of a supportive therapeutic environment and the spontaneous improvement that is commonly seen when measurements of symptoms and cardiac function are repeated frequently over long intervals of time. Three months of treatment with a placebo produces a reduction in symptoms in 25% to 35% of patients, an increase in cardiac output and a decrease in pulmonary wedge pressure, and an increase in exercise tolerance of up to 90 to 120 seconds. Physicians commonly seek to maximize the "placebo effect," since the goal of treatment in the clinical setting is to improve the quality of the patient's life. On the other hand, clinical investigators seek to minimize the "placebo effect," since the goal of a research study is to test the hypothesis that the new drug is superior to a placebo.
Molecular genetic basis of maple syrup urine disease in a family with two defective alleles for branched chain acyltransferase and localization of the gene to human chromosome 1. Maple syrup urine disease in humans results from inherited defects in branched chain alpha-ketoacid dehydrogenase, a mitochondrial multienzyme complex. A variety of genetic changes may produce this phenotype by affecting the function of any of the three complex-specific subunits. The varied clinical expression observed in patients may be partially explained by the defects in the involved subunit. Here we report localization of the gene for the branched chain acyltransferase component of the complex to human chromosome 1 and describe a proband who is a compound heterozygote at this locus. One allele, inherited from the father, produces transcripts with 124 nucleotides deleted from the coding region. The deletion is not found in the branched chain acyltransferase gene, implying that the deleted transcripts arise by an error in transcript processing. Cells from the patient's mother contain 50% of the normal amount of mRNA for the subunit, and the proband has inherited this nonexpressing allele from her. As a result, the proband produces no acyltransferase protein and therefore has greatly impaired complex activity. A phenotypically normal sibling is shown to be genetically similar to the mother having inherited the mother's nonexpressing allele and the father's normal allele.
Exercise thallium-201 scintigraphy in the diagnosis and prognosis of coronary artery disease. OBJECTIVE: To determine the discriminant accuracy of exercise thallium-201 myocardial perfusion scintigraphy for the diagnosis and prognosis of patients with known or suspected coronary artery disease. DATA IDENTIFICATION: A survey of the National Library of Medicine MEDLINE database. STUDY SELECTION: The key medical subject headings used were coronary disease, myocardial infarction, radionuclide imaging, and thallium. A total of 122 retrieved studies were considered relevant and were reviewed in depth. DATA EXTRACTION: Only studies reporting both the sensitivity and specificity of thallium scintigraphy were analyzed. RESULTS: Discriminant accuracy for diagnosis and prognosis was summarized in terms of pooled sensitivity and specificity. CONCLUSIONS: Exercise thallium scintigraphy is useful in the noninvasive diagnosis of coronary artery disease, especially in patients with abnormal resting electrocardiograms, restricted exercise tolerance, and intermediate probability of having disease at the time of testing as well as of defining the prognosis of patients with known or suspected coronary artery disease, especially in those with previous myocardial infarction. Because of various shortcomings in the published record, however, the marginal discriminant accuracy and cost effectiveness of thallium scintigraphy compared with conventional clinical assessment and exercise electrocardiography remain controversial.
Antibodies directed against neutrophils (C-ANCA and P-ANCA) are of distinct diagnostic value in systemic vasculitis. In a prospective study, sera from over 700 patients with suspected vasculitis, including over 200 patients undergoing renal biopsy, were examined for antibodies to neutrophil cytoplasmic antigen (ANCA). An indirect immunofluorescence assay on ethanol fixed human neutrophils identified two types of autoantibody: C-ANCA, which produces diffuse cytoplasmic staining and P-ANCA, which produces an artefactual nuclear/perinuclear staining pattern. The diagnosis of patients in whom ANCA of either form was found was established following case note review according to defined diagnostic criteria. Forty of 45 patients whose sera contained C-ANCA at a titre of greater than or equal to 1/40 satisfied the diagnostic criteria for Wegener's granulomatosis or microscopic polyarteritis. Twelve of 30 patients with P-ANCA at a titre of greater than or equal to 1/40 were also classified as having one of these disorders. Seventeen of the remaining 18 patients had immune-mediated disorders with deep organ damage. Of 47 ANCA-positive patients who underwent renal biopsy, 21 had glomerulonephritis associated with Wegener's glomerulonephritis and a further 22 had a necrotizing or crescentic glomerulonephritis. Ethanol fixation is important for discrimination of C-ANCA and P-ANCA. C-ANCA are highly specific for Wegener's granulomatosis and microscopic polyarteritis. In patients undergoing renal biopsy, the presence of these antibodies is highly specific for a necrotizing or crescentic glomerulonephritis.
Serum keratan sulfate. Quantitative and qualitative comparisons in inflammatory versus noninflammatory arthritides. The concentration of keratan sulfate (KS) epitope was measured in the serum of patients with osteoarthritis (OA) or rheumatoid arthritis (RA) by enzyme-linked immunosorbent assay and compared with that in the serum of patients with primary fibromyalgia syndrome (PFS) and of controls who had no joint disease. By Student's tau-test, the mean serum KS concentrations in OA and RA patients measured with monoclonal antibodies (MAb) 5-D-4 and 2-D-3 were significantly increased over those in the PFS and normal groups; similar findings were observed using a nonparametric test, except that levels in RA patients showed no difference from those in PFS patients and normal subjects. There was no significant correlation between joint scores or disease duration and KS levels in OA or RA patients. Gel filtration of sera revealed mainly large, polydisperse KS-bearing fragments which eluted in a broad profile. KS purified from sera by immunoaffinity chromatography consisted mainly of high-density proteoglycans. Electrophoresis of pooled high-density KS fractions in polyacrylamide-agarose gels followed by Western blotting with MAb 5-D-4 showed diffuse bands with relative mobilities corresponding to large proteoglycans. These findings are consistent with attachment of KS to protein core fragments of various sizes; KS in patient sera is comparable in size with that in normal sera. Elevations of serum KS levels occur in the presence of cartilage degradation, but do not quantitatively define the extent or duration of articular involvement.
Progressing cerebral infarction in relation to plasma glucose in gerbils. We studied neurologic morbidity and its evolution during hyperglycemia induced immediately after permanent unilateral common carotid artery ligation in Mongolian gerbils. A total of 60 animals were divided into five groups: one experiencing severe hyperglycemia for 1 hour after the onset of ischemia (brief hyperglycemia group, n = 13), a normoglycemic control group for the brief hyperglycemia group (n = 12), a group with severe hyperglycemia for 4 hours after the onset of ischemia (prolonged hyperglycemia group, n = 11), a normoglycemic control group for the prolonged hyperglycemia group (n = 13), and a hyperosmolar normoglycemic control group for the prolonged hyperglycemia group (n = 11). Neurologic morbidity and mortality were higher in the two hyperglycemic groups than in the three normoglycemic control groups. The neurologic deficit progressed according to the duration of severe hyperglycemia. In the three normoglycemic control groups neurologic status stabilized 120 minutes after the onset of ischemia, in the brief hyperglycemia group stabilization occurred at 210 minutes, and in the prolonged hyperglycemia group neurologic deficit progressed for approximately 360 minutes, coinciding with the death of all but one gerbil, in which the neurologic deficit remained stable until death 23 hours after ischemia. We suggest that hyperglycemia is another cause of progressing cerebral infarction.
Stiff-man syndrome. Stiff-man syndrome (Moersch-Woltman syndrome) is a rare disorder of motor function characterized by involuntary stiffness of axial muscles and superimposed painful muscle spasms, which are often induced by startle or emotional stimuli. The standard treatment has been benzodiazepines. An association has been reported between stiff-man syndrome and epilepsy, insulin-dependent diabetes, and a variety of organ-specific autoimmune disorders. Antibodies directed against glutamic acid decarboxylase and against pancreatic islet cells have been detected in the serum and cerebrospinal of patients with stiff-man syndrome. These findings suggest that stiff-man syndrome may be an autoimmune disease. Preliminary reports indicate that patients with stiff-man syndrome have a favorable response to plasma exchange and corticosteroid therapy.
Comparison of thallium-201 and technetium-99m hexakis 2-methoxyisobutyl isonitrile single-photon emission computed tomography for estimating the extent of myocardial ischemia and infarction in coronary artery disease. Single-photon emission computed tomography (SPECT) using thallium-201 (Tl-201) was compared with technetium-99m hexakis 2-methoxyisobutyl isonitrile (Tc-99m MIBI) in 24 patients with coronary artery diseaes. Patients exercised to the same work load as each isotope was studied. Normal and hypoperfused left ventricular mass was determined with an automated method. Estimated total left ventricular mass was similar for both stress/redistribution Tl-201 and stress/rest Tc-99m MIBI images. The mean estimated defect size in the redistribution Tl-201 images was 32 +/- 34.7 vs 33 +/- 38.4 g in the resting Tc-99m MIBI studies (difference not significant). The individual determinations of defect mass were highly correlated (r = 0.93; p less than 0.0001). Estimated defect size in the stress Tl-201 images (52 +/- 46.2 g) was significantly larger than the exercise Tc-99m MIBI estimates of defect mass (42 +/- 39.9 g; p less than 0.05). A linear correlation existed between stress thallium and technetium estimates of defect size (r = 0.85) but 15 of 24 Tc-99m MIBI defects were smaller than the Tl-201 defects. Partial redistribution of Tc-99m MIBI could explain the discordance. Stress Tc-99m MIBI SPECT defect size determined by visual interpretation or by the use of isocount analysis may be smaller than what is seen with stress Tl-201 SPECT.
Eight and 12 week courses of cyclophosphamide in nephrotic syndrome Seventy-three children with steroid dependent minimal change nephrotic syndrome were randomly allocated to receive treatment with cyclophosphamide (2 mg/kg/day) for either eight or 12 weeks, in combination with prednisolone. All patients had previously relapsed while the dosage was being reduced or within 14 days of discontinuing prednisolone in the six months before receiving cyclophosphamide treatment (steroid dependent), and had severe steroid toxicity. Thirty two patients were treated with cyclophosphamide for eight weeks, and 41 for 12 weeks. There were no differences between the two groups in age at onset of nephrosis or entry into the study, sex ratio, duration of nephrosis, number of relapses before entry, and follow up period after entry. The relapse free rate of patients treated for eight weeks (25%) was similar to that of those treated for 12 weeks (24%) five years after stopping the treatment, and the mean relapse free interval and the sparing effect of cyclophosphamide (if any) on subsequent treatment with steroids did not differ between the groups. We conclude that cyclophosphamide should be used for no longer than eight weeks at a dose of 2 mg/kg/day in children with steroid dependent minimal change nephrotic syndrome.
Effect of antileukemia chemotherapy on marrow, blood, and oral granulocyte counts. This study was designed to elicit the effects of antileukemia chemotherapy on marrow production, blood carriage, and oral extravasation of granulocytes, and on the phagocytic activity of those harvested from the mouth. Fifteen adult patients with various morphologic forms of acute leukemia were followed through one to four courses of chemotherapy. Oral saline rinse samples were obtained thrice weekly and prepared for enumeration in a hemocytometer. The oral granulocyte counts were compared with concurrent counts in the bone marrow and peripheral blood. Phagocytic activity of the oral granulocytes was measured by the method of Smith and Rommel. The 15 patients were followed through 30 courses of chemotherapy and recovery. During each, there was a drug-induced decrease in marrow, blood, and oral granulocytes that was reversed when therapy was discontinued and bone marrow activity was restored. Phagocytic activity of the oral granulocytes was not perceptibly affected by the antileukemic drugs. Oral granulocyte counts provide a noninvasive method for monitoring the onset and recovery of chemotherapy-induced myelosuppression and granulocytopenia in patients with leukemia.
Treatment planning for internal radionuclide therapy: three-dimensional dosimetry for nonuniformly distributed radionuclides. A calculational approach is described that provides the spatially varying radiation absorbed dose, presented as isodose contours superimposed on CT images, from nonuniform and/or irregular cumulated activity distributions. CT images are read from magnetic tape and are displayed on a high-resolution color graphics display monitor. Source tissue geometries are defined on a series of contiguous CT images automatically (by an edge detection algorithm) or manually (using a trackball), thereby obtaining a three-dimensional representation of the various source volumes of activity. Dose calculations are performed using a radionuclide-specific absorbed dose point kernel in the form of a lookup table. The method described yields the spatially varying dose delivered to tumor and normal tissue volumes from a patient-specific cumulated activity distribution in a clinically implementable manner. This level of accuracy in determining normal tissue and tumor doses may prove valuable in the evaluation and implementation of radionuclides and radiolabeled compounds for therapeutic purposes.
Late metastases of cutaneous melanoma: case report and literature review. The development of delayed metastases, although rare, is well documented in patients with invasive cutaneous melanoma. Only 24 cases, including ours, are clearly documented in the literature. We describe a 56-year-old woman who had an acral lentiginous melanoma of the right hand (thickness 1.2 mm). Thirteen years after excision and postoperative irradiation, a subcutaneous metastasis developed in the right arm. One year later the patient died with disseminated bone metastases. This case, as with most of those with delayed metastases, has typical features: female sex; location at a site other than the back, arm, neck, or scalp; and primary tumor thickness between 1.2 and 2.5 mm.