123rc/medical_text huggingface dataset:
Bcr/abl recombinant DNA analysis versus karyotype in the diagnosis and therapeutic monitoring of chronic myeloid leukemia. Karyotype and bcr/abl recombinant DNA analyses are two means of detecting the chromosomal aberration in chronic myeloid leukemia. The authors compared these two methods in a retrospective study of 36 patients with CML in which they found the bcr/abl DNA recombinant event in 100% (29 of 29) of those patients who had the Philadelphia chromosome. To achieve this sensitivity, a battery of two bcr probes and three restriction enzymes is necessary. The authors propose a sequential algorithm for efficient use of these probes and enzymes. In 76% of the patients, bcr/abl rearrangement can be detected with a Bgl II digest and a 3' commercial probe. An additional 21% of patients can be detected by a second assay in which the same membrane is rehybridized to a 3' and 5' combination bcr probe. One patient (3%) required an additional restriction enzyme digest with BamH I to detect the recombinant event by the same 3' probe. Karyotype analysis is used to determine cytogenetic remission in patients with CML under therapy. The authors studied the use of DNA analysis by the Southern blot technique to detect a decrease in the relative number of leukemic cells. By dilution studies and densitometric scanning of autoradiographs, the authors were able to detect a 15% decrease in the relative number of cells having the bcr/abl recombinant event. The authors report the preliminary results of three patients in whom they compared the karyotype and recombinant DNA analysis at multiple time points in their clinical course. In conclusion, the bcr/abl recombinant DNA analysis is superior to karyotype for the diagnosis of CML and can be used for monitoring treated patients.
Echocardiographic evaluation of cardiac structure and function in elderly subjects with isolated systolic hypertension One hundred four participants in the Systolic Hypertension in the Elderly Program (SHEP) trial (mean age 71 +/- 6 years) were examined by Doppler echocardiography to gain information on the cardiac structural and functional alterations in isolated systolic hypertension. Participants had a systolic blood pressure greater than 160 mm Hg with diastolic blood pressure less than 90 mm Hg and were compared with 55 age-matched normotensive control subjects. Left ventricular mass index was significantly higher in the participants than in the normotensive subjects (103 +/- 28 versus 87 +/- 23 g/m2, p = 0.0014) and 26% of the participants met echocardiographic criteria for left ventricular hypertrophy compared with 10% of normotensive subjects. Left atrial index was also greater in participants than in normotensive subjects (2.26 +/- 0.32 versus 2.11 +/- 0.24 cm/m2, p = 0.005) and 51% of participants had left atrial enlargement. Doppler measures of diastolic filling were significantly different between the two groups, with peak atrial velocity higher (76 +/- 17 versus 69 +/- 17 cm/s, p = 0.02) and ratio of peak early to atrial velocity lower (0.76 +/- 0.23 versus 0.86 +/- 0.22, p = 0.0124) in participants. There was no correlation between left ventricular mass index and Doppler measures of diastolic function, but relative wall thickness correlated significantly with peak atrial velocity (r = 0.22, p = 0.016) and peak early to peak atrial velocity ratio (r = 0.24, p = 0.007). There was no difference in M-mode ejection phase indexes of systolic performance (shortening fraction and peak velocity of circumferential fiber shortening) between the two groups.
Peritoneal dialysis in the geriatric patient. Elderly patients on chronic peritoneal dialysis (CPD) from two large chronic peritoneal dialysis programs were compared with younger patients in regard to peritonitis rates, catheter problems, hospital days, transfers to other forms of therapy, and mortality. Peritonitis rates and organisms were similar in younger and older patients. Catheter replacements were less common in the elderly. Differences in hospital days were attributable to hospitalization for vascular disease. The elderly were more likely to have the first episode of peritonitis, to die and to change dialysis modalities at all times after the first year of continuous ambulatory peritoneal dialysis (CAPD) treatment, although other than increased mortality, differences between the two groups were small. CPD appears to be an acceptable form of renal replacement therapy in the elderly.
Conduction system injury after aortic valve dilation in the dog single- versus double-balloon catheters. The range of morbidity induced by valvuloplasty is not fully known, but transient conduction disturbances are common. The authors performed aortic valve balloon dilatation on 10 closed-chest dogs with normal aortic valves, using a femoral cutdown approach and fluoroscopic guidance. Four were done with a single 15 mm balloon catheter, and in the other 6 two 12 mm balloon catheters were used. Balloons were inflated to 5 to 12 atms pressure with contrast solution. After several inflations the dogs were sacrificed, the hearts removed and examined. Gross examinations revealed subendocardial hemorrhage in the outflow tract in 5 of the 6 in which double balloons had been used. Microscopically, all aortic valve areas showed hemorrhage, mostly in loose connective tissues of the valve leaflets. The severity of injury appeared greater when two balloons had been used. Histologic examination showed definite injury to the myocytes of the left bundle branch in all 6 of the double-ballooned dogs, but in none of those subjected to the single-balloon procedure. During aortic valve dilation the only manifestation of conduction system injury was prolongation of the QRS complex in 3 of the 6 dogs in which a double-balloon catheter had been used. The results suggest that electrocardiographic conduction disturbances observed in patients undergoing aortic valvuloplasty may be the result of direct injury of conduction tissue and may be more likely to occur when larger balloons are used.
Esophageal reflux before and after isolated myotomy for achalasia. Four patients with achalasia underwent 24-hour esophageal pH measurements as ambulatory patients before and after limited myotomy without fundoplication. Resting lower esophageal sphincter pressure was reduced from 24.3 +/- 1.3 mm Hg to 7.5 +/- 4.3 mm Hg. No significant differences (p greater than 0.05) were found before and after operation in the total 24-hour pH data distribution (pH 6.24 +/- 0.84 vs 5.75 +/- 1.03), the fraction of time below pH 4.0 (4.8% +/- 5.3% vs 8.0% +/- 6.9%), or the mean duration of reflux episodes greater than 5 minutes (22.8 +/- 18.8 minutes vs 23.0 +/- 10 minutes), all +/- SD. Effective relief of esophageal obstruction in achalasia is feasible by isolated limited myotomy without producing gastroesophageal reflux.
A rodent model of cirrhosis, ascites, and bacterial peritonitis. We sought to develop a rodent model of spontaneous bacterial peritonitis and report here the preliminary results of carbon tetrachloride-induced cirrhosis in which ascites and bacterial peritonitis predictably develop. Of 41 rats that survived the initial carbon tetrachloride toxicity, 38 (92.7%) developed cirrhosis with ascites. Of these 38, 21 (55.3%) developed 24 episodes of ascitic fluid infection without iatrogenic colonization. No surgically treatable source of infection was identified at autopsy in any rat; therefore, the infections were presumed to be "spontaneous." Eight (50%) of the 16 rats with culture-positive ascitic fluid at postmortem examination also had spontaneous pleural fluid infection with the same organism. Escherichia coli and Proteus sp. were the organisms most commonly isolated. This rodent model of cirrhosis with ascites appears to be the first high-yield animal model of spontaneous bacterial peritonitis. Ascitic fluid infection in these rats resembles ascitic fluid infection in humans. This model will allow further investigation of the mechanisms of pathogenesis of ascitic fluid infection and provide insight into the prevention and treatment of spontaneous bacterial peritonitis and pleural fluid infection in patients with cirrhosis.
Usefulness of epidurally evoked cortical potential monitoring during cervicomedullary glioma surgery. This report describes a patient with an intramedullary ependymoma at the region of the cervicomedullary junction in whom there was an abolition of somatosensory evoked potentials following median nerve stimulation. During intraoperative monitoring of cortical potentials elicited by epidural cervical cord stimulation, the tumor was removed. Posterior epidural stimulation appeared to depolarize more ascending fibers than did stimulation of a single peripheral nerve. We recommend that, in cases of operations in this vital area, epidurally evoked cortical potentials be monitored intraoperatively.
Management of symptomatic lymphocele via percutaneous drainage and sclerotherapy with tetracycline. Lymph collections following pelvic surgery are usually asymptomatic, but may occasionally produce symptoms requiring invasive therapy. We have successfully obliterated a large lymphocele by employing percutaneous drainage and instilling tetracycline.
Tympanosclerosis of the middle ear: late results of surgical treatment. The late results of one stage operation for middle ear tymanosclerosis in 73 patients during the period January 1965 to December 1980 are presented. Mean observation time was 11.2 years (range 3-20.2 years), with a follow-up rate 86 per cent. Among 64 patients with stapes fixation, 59 had removal of tympanosclerotic masses and stapes mobilization, and five cases underwent stapedectomy. The series was divided into six groups and the results analyzed. The best and most stable results occurred in the group with stapes mobilization and an intact ossicular chain followed by the group with stapes mobilization and Type II tympanoplasty with incus interposition. The poorest late results were obtained in ears with lacking stapes crura and stapes mobilization, and in ears subjected to stapedectomy. No case of post-operative sensorineural hearing loss occurred. We recommend that care is taken to preserve an intact ossicular chain at stapes mobilization performed at the same stage as myringoplasty. Also in ears with a defective ossicular chain but intact stapes with tympanosclerotic fixation we recommend stapes mobilization in one stage. In ears with fixation of the stapes footplate and defective crura, we recommend stapedectomy or stapedotomy in two stages.
Clinical cardiovascular magnetic resonance imaging. Magnetic resonance imaging (MRI) is a powerful tool providing high-resolution images of the heart and great vessels without the use of ionizing radiation or contrast agents. MRI systems currently in use at many hospitals can be used effectively in the routine, clinical evaluation of many forms of cardiovascular disease, including great vessel disease, ischemic cardiac disease and congenital cardiac disease. Moreover, quantitative and cine MRI techniques are now available, which provide highly accurate measures of chamber size, wall motion and wall thickening. Recent developments in the areas of myocardial tagging, high-speed imaging and MR assessments of flow and perfusion suggest potential for an increasing role of MRI in the clinical evaluation of the cardiovascular system.
Fractionated high dose rate versus low dose rate regimens for intracavitary brachytherapy of the cervix. I. General considerations based on radiobiology. Intracavitary brachytherapy at low dose rate (LDR), often with the addition of external-beam radiotherapy, has long been considered the treatment of choice for carcinoma of the cervix, maximizing acute damage in the treatment volume, whilst minimizing late effects. In recent years, primarily for reasons of convenience and cost, there has been a move towards treatments involving a few fractions at high dose rate (HDR). Using data from cells of human origin cultured in vitro, we make estimates of the doses that, delivered in 2-12 HDR fractions, produce tumour control and early effects equivalent to intracavitary treatments at LDR. We also show that, for situations where the normal-tissue dose responsible for late effects is significantly smaller than the tumour dose, HDR schemes may be devised which, while yielding early killing comparable with that of LDR, should not result in worse late effects. We suggest that this scenario probably applies to treatment of carcinoma of the cervix.
Diagnostic and prognostic value of electrophysiologic tests in meralgia paresthetica. Electrophysiologic diagnosis of unilateral meralgia paresthetica is usually assessed by side-to-side comparison of SNAP amplitudes, SNCVs, and SEP latencies following stimulation of lateral femoral cutaneous nerves. To determine the relevance for diagnosis of these tests and side-to-side comparison, the results were compared in patients with unilateral meralgia paresthetica and normal subjects. The long-term outcome was also considered, in order to determine whether electrophysiologic findings contribute to the prognosis. In our study, SNAP amplitude comparison was found to be more useful for diagnosis than SNCV and SEP latency comparisons. However the value of the SNAP amplitude on the affected side, just as the results of the other tests, was not found to be predictive of the outcome. Also the results of the tests depend on the methods used and on the nerve's route.
A comparison of induction and maintenance therapy for acute nonlymphocytic leukemia in childhood: results of a Pediatric Oncology Group study. Two hundred fifty-six children with previously untreated acute nonlymphocytic leukemia (ANLL) were evaluated on a Pediatric Oncology Group (POG) phase III randomized trial of both induction and continuation chemotherapies. Induction therapy compared vincristine, cytarabine, and dexamethasone (VADx) with daunorubicin, cytarabine, and thioguanine (DAT). The complete remission (CR) rate using DAT was superior (82% v 61%, P = .02). Postremission therapy consisted of either "standard" two-cycle therapy or a more intensive four-cycle regimen given for 2 years. Overall, there was no difference in outcome for patients randomized to either continuation regimen. The overall complete continuous remission rate (CCR) for the "best" induction/continuation therapy combination at 2 years was .50 (SE = .06), at 3 years was .35 (.04), and at 4 years was .34 (.05). Analysis of selected clinical and laboratory parameters demonstrated differences in induction responses favoring DAT induction but did not impact eventual disease-free survival. There were two subgroups of patients who responded better to four-cycle continuation therapy. These were patients with French-American-British (FAB) M1/M2 (2-year CCR was .20 v .44, P = .01) and patients older than 10 years at diagnosis (.32 v .62, P = .004).
Simultaneous superior oblique sheathectomy and inferior oblique tuck in congenital Brown's syndrome. Since Harold Brown, in 1950, described the superior oblique tendon sheath syndrome, numerous surgical techniques have been explored to treat this condition. Tenectomy of the homolateral superior oblique, alone or in combination with a weakening procedure on the homolateral inferior oblique, has been the technique most advocated. However, good functional results are rarely achieved in a single procedure, and delayed complications are frequent. Taking advantage of the improved dissection and reduced trauma afforded by the use of a surgical microscope, one of the techniques first recommended and later abandoned by Brown was reappraised. The technique consists of dissection of the sheath and attachments of the superior oblique, while preserving its tendon, combined with a 10mm tuck of the homolateral inferior oblique. Both a typical and a severe atypical congenital case, according to the classification of Brown, were treated in this fashion. Full correction was achieved in both.
Double-peaking circadian variation in the occurrence of sustained supraventricular tachyarrhythmias. We studied 251 patients less than or equal to 65 years of age admitted for treatment of symptomatic supraventricular tachyarrhythmia to assess whether these arrhythmias begin evenly throughout the day or manifest circadian variation in occurrence. The arrhythmias included 152 episodes of atrial fibrillation, 50 episodes of supraventricular reentry tachycardia, 30 episodes of atrial flutter, and 19 cases of ectopic atrial tachycardia. A total of 209 patients could tell the exact time their symptoms had started. In 38 of them (18%), the arrhythmia had begun between midnight and 6:00 AM, in 63 (30%) between 6:01 AM and noon, in 46 (22%) between noon and 6:00 PM, and in 62 (30%) between 6:01 PM and midnight. This distribution differed significantly from uniform occurrence (chi square 8.7, p less than 0.05). Fifty patients were using beta-adrenoceptor blocking agents when the arrhythmia occurred. Compared with the other 159 patients, they had no morning surge of arrhythmias (20% versus 33.3% of episodes between 6:01 AM and noon), but instead a much higher incidence at night (34% versus 13.2% of episodes between midnight and 6:00 AM) (chi square 14.4, p less than 0.005). We conclude that the frequency of onset of sustained supraventricular tachyarrhythmias varies with the time of day, showing nearly equal peaks in the morning and in the evening and a trough at night. The modifying effect of beta-adrenoceptor blockage suggests that many morning arrhythmias are of adrenergic origin while other, probably vagal arrhythmogenic mechanisms, prevail at night.
Automated immunohistochemical estrogen receptor in fixed embedded breast carcinomas. The authors immunohistochemically assessed the presence of estrogen receptor (ER) in formalin-fixed, paraffin-embedded tissue sections of 68 breast carcinomas by an automated method using Pronase (CalBiochem, La Jolla, CA) predigestion and alkaline phosphatase detection (Method 1). These results were compared with those obtained by an automated peroxidase-antiperoxidase method with DNAse pretreatment of fixed embedded sections (Method 2), with ER immunostain on frozen sections (Method 3), and with biochemical results (dextran-coated charcoal cytosolic [DCC] assay). Compared with the DCC assay, Methods 1, 2, and 3 gave sensitivities of 54%, 25%, and 89%, respectively. The sensitivity for Method 1 was increased to 74% in those cases with DCC results showing greater than 50 fmol/mg protein. These findings indicate that ER immunohistochemical studies on formalin-fixed paraffin-embedded tissues (as assayed by Method 1) provide useful clinical information when the results are positive. A negative result, especially if surrounding normal elements are not positive, may indicate no receptors, receptor levels less than 50 fmol/mg protein, or improper tissue preservation. In the absence of fresh tissue for ER assay by DCC assay or of frozen sections for immunostaining, and with an understanding of its limitations, this method may be useful.
Management of mycotic rupture of the ascending aorta after heart-lung transplantation. A 19-year-old woman underwent heart-lung transplantation for obstructive bronchiolitis. Eleven days later mycotic rupture of the ascending aorta occurred. Emergency cardiopulmonary bypass was instituted via the femoral vessels and the chest was reopened under cardiac massage. Perforation of the aorta at the site of insertion of the cardioplegic cannula in the donor aorta was seen. Under circulatory arrest the infected area was excised, a pericardial patch plasty was performed, and the region was covered with a muscle flap. Postoperatively, Candida albicans was found in the excised specimen of the aorta, in drainage fluid, and in the bronchoalveolar lavage. High doses of antimycotics were administered intravenously and for irrigation of the mediastinum, which resulted in an eradication of fungi in all cultures 7 days later. Six weeks after reoperation the patient was discharged home, and she remains well 9 months postoperatively.
Mechanisms associated with the generation of biologically active human immunodeficiency virus type 1 particles from defective proviruses. The human immunodeficiency virus (HIV) is the etiological agent of acquired immunodeficiency syndrome (AIDS). HIV exhibits extensive genetic diversity and it is apparent that an infected individual contains different populations of distinct viral strains, a large proportion of which has been found surprisingly to be defective for replication. A similar phenomenon has also been observed with some cell lines that are known to produce infectious viral particles but harbor defective proviral genomes. Here, we investigated the molecular basis of this phenomenon by cloning proviral genomes of HIV from a cell line that was capable of producing high titers of biologically active HIV particles that readily induced syncytia with CD4+ cell lines and peripheral blood lymphocytes. This cell line was found to contain five proviral genomes, all of which, when tested individually, failed to produce replication-competent viruses upon transfection into human cells. However, when a specific combination of two proviral genomes was used in such transfection studies, it was possible to obtain biologically active, replication-competent viral particles that infected and replicated in CD4+ cell lines and induced syncytia characteristic of HIV. Such a result may be due to homologous recombination between proviral DNAs occurring in cells after transfection and/or complementation of replication-defective proviral DNAs. The diploid nature of the viral RNA genome present in the viral particle may enable the persistence of defective HIV genomes.
Hyperfunctioning metastatic follicular thyroid carcinoma in Pendred's syndrome. A 66-year-old woman with Pendred's syndrome underwent a partial thyroidectomy when she was 17 years old. At the age of 52 years, she had a second thyroid operation because of hyperthyroidism due to a toxic multinodular goiter with a mediastinal extension consisting of several separate nodules. Five years later a hyperfunctioning metastatic follicular carcinoma was diagnosed histologically. After treatment with radioactive iodine, the patient was well. To the authors' knowledge, this is the first description of a metastatic follicular thyroid carcinoma in Pendred's syndrome and the first report of hyperthyroidism occurring after malignant degeneration of a dyshormonogenetic goiter.
Membrane oxygenator prevents lung reperfusion injury in canine cardiopulmonary bypass The effect of blood activation on lung reperfusion injury during cardiopulmonary bypass was investigated in 20 dogs with the use of a bubble oxygenator (n = 10) or a membrane oxygenator (n = 10). In the bubble oxygenator group, significant leukocyte and platelet right to left atrium gradients were found 15 minutes after lung reperfusion (p less than 0.05, p less than 0.01) accompanied by a sharp increase in plasma malondialdehyde concentration 5 minutes after lung reperfusion, whereas no significant right to left atrium gradient of leukocytes or platelets nor significant increase in plasma malondialdehyde concentration was observed in the membrane oxygenator group. In both the bubble oxygenator and membrane oxygenator group, similar mild to moderate lung histological changes were found before lung reperfusion. After lung reperfusion, however, more endothelial cell swelling (p less than 0.05), leukocyte (p less than 0.01) and platelet (p less than 0.01) accumulation in lung capillaries, leakage of erythrocytes into the alveolar space (p less than 0.05), and type I cell damage (p less than 0.05) were found only in the bubble oxygenator group. Eventually, a significantly higher lung water content was found in the bubble oxygenator group than in the membrane oxygenator group (p less than 0.01) after cardiopulmonary bypass. This study indicated that lung injury during cardiopulmonary bypass starts mainly after lung reperfusion, which was correlated with lung leukocyte and platelet sequestration associated with different types of oxygenators.