123rc/medical_text huggingface dataset:
A case of massive true thymic hyperplasia with non-Hodgkin's lymphoma. A case of massive true thymic hyperplasia with non-Hodgkin's lymphoma of the mediastinum is reported in a 14-year-old boy. Computed tomographic scan of the chest showed a mass of the anterior mediastinum and conspicuous swelling of the lymph nodes in the upper and lower mediastinum. They were grossly resected. The tumor of the anterior mediastinum was histologically diagnosed as true thymic hyperplasia. All of the mediastinal lymph nodes were diagnosed as non-Hodgkin's lymphoma, diffuse, mixed small and large cell type.
The molecular genetic basis of Glanzmann thrombasthenia in the Iraqi-Jewish and Arab populations in Israel. Glanzmann thrombasthenia is an autosomal recessive bleeding disorder characterized by a decrease or absence of functional platelet glycoprotein (GP) IIb-IIIa (alpha IIb beta 3) integrin receptors. Although thrombasthenia is a rare disorder, its occurrence is increased in some regions of the world where intracommunity marriage and consanguinity are commonplace, resulting in increased expression of autosomal recessive traits. We have been studying two populations having an unusually high frequency of Glanzmann disease, Iraqi Jews and Arabs living in Israel, and were able to distinguish the populations on the basis of immunodetectable GPIIIa and platelet surface vitronectin receptor (alpha v beta 3) expression. In this article, we describe molecular genetic studies based on use of the PCR that have allowed us to characterize platelet mRNA sequences encoding GPIIb and GPIIIa from patients in these populations. In six of six Iraqi-Jewish families studied, cDNA sequence analysis identified an 11-base deletion within exon 12 of the GPIIIa gene. This mutation produces a frameshift leading to protein termination shortly before the transmembrane domain of GPIIIa. In contrast, a 13-base deletion encompassing the splice acceptor site of exon 4 of the GPIIb gene was found in three of five Arab kindreds studied. This deletion results in forced alternative splicing to a downstream AG acceptor, producing a 6-amino acid deletion in the GPIIb protein, including a single cysteine residue. These nucleotide sequence variations were exploited to design a rapid, PCR-based oligonucleotide dot-blot hybridization test for both pre- and postnatal diagnosis of Glanzmann disease. These studies demonstrate the heterogeneity of Glanzmann thrombasthenia in different populations, and its homogeneity within geographically restricted populations, and offer insight into the requirements for integrin surface expression.
Changes in ventricular fibrillation threshold during the development of perinephritic hypertension. Established hypertension is associated with enhanced susceptibility to life-threatening arrhythmias. However, little is known about the effects of the development of hypertension on the electro-physiological properties of the heart. To study this relationship, dogs were chronically instrumented for recording mean arterial pressure and conducting cardiac electrical testing during right ventricular pacing using an intracavitary bipolar catheter. In normotension, ventricular fibrillation threshold was determined under alpha-chloralose anesthesia, after which perinephritic hypertension was induced by wrapping one kidney in silk followed by contralateral nephrectomy. During serial testing of the same animals, ventricular fibrillation threshold was significantly increased early in the development of hypertension (2 to 3 weeks after renal wrapping), but found to be significantly reduced at 6 to 7 weeks after renal wrapping. The increase in ventricular fibrillation threshold was eliminated by cholinergic blockade.
Adjuvant, specific, active immunotherapy for resectable squamous cell lung carcinoma: a 5-year survival analysis. In 1976 Stewart et al. (Annals of the New York Academy of Sciences 277:436-466) reported the effectiveness of adjuvant specific active immunotherapy of lung carcinoma in improving the postoperative survival of stage I lung carcinoma patients in a phase II study using lung carcinoma-associated antigen (TAA) and complete Freund's adjuvant (CFA). A phase III study was then designed by the authors to see the effects of specific active immunotherapy compared to the conventional management (no treatment) and to nonspecific immunotherapy. From 1976 to 1981, 85 patients with resectable (stages I and II) squamous cell lung carcinoma were entered into a randomized study: 1) control group; 2) specific immunotherapy group--three monthly doses of 500 micrograms of TAA emulsified with CFA; 3) nonspecific immunotherapy group--three monthly doses of CFA emulsified in saline. All the patients in the study received skin tests with 100 micrograms of the same TAA used for the immunotherapy. Recently, a 5-year follow-up of all the patients became available: The life table 5-year survival of group 1 was 34%, of group 2 was 75%, and of group 3 was 53%. The median survivals for the three groups were group 1, 38 months; group 2, 106 months; and group 3, 71 months. The difference was significant at P = .007 (Cox-Mantel test).
Characterization of the effect of two 4-methyl piperidine derivatives of hemicholinium-3, A-4 and A-5, on choline transport. A-4 and A-5 are tertiary and N-methyl quaternary 4-methylpiperidine analogs of hemicholinium-3 (HC-3). Previous work in this laboratory has shown A-4 and A-5 to be inhibitors of the sodium-dependent, high affinity choline uptake system (SDHACU). Their effects on choline transport were characterized further using neuroblastoma 41A3 cells. These cells rapidly take up choline through two separate mechanisms: a SDHACU system and a sodium-independent, low affinity uptake system (SILACU). A-4, A-5 and HC-3 decreased 5 microM choline transport in a dose-dependent fashion. The compounds were unable to decrease choline transport at 250 microM choline suggesting that they are inactive with respect to SILACU. All three compounds significantly increased the Km but not the Vmax for the SDHACU system, suggesting a competitive mechanism of inhibition. Ki values ranged from 18 to 25 microM for A-4, 20 to 26 microM for A-5 and 68 to 75 microM for HC-3. Dose-response curves for inhibition of choline transport by A-5 and HC-3 were not changed by a 24-hr pre-exposure of the cells to each inhibitor. However, after a 24-hr pre-exposure to A-4, a significantly different dose-response curve was obtained compared to the dose-response curve for A-4 in untreated cells. After a 24-hr pre-exposure, a 4-hr recovery period was sufficient to remove the effect of each compound. These data suggest that A-4 and A-5, like HC-3, inhibit the SDHACU, competitively and reversibly.
New developments in cardiopulmonary resuscitation. Since the last revision of the American Heart Association's guidelines in 1985, several new developments of clinical importance have occurred in the field of cardiopulmonary resuscitation. These include enhanced access to and earlier use of defibrillation, the use of high-dose epinephrine when standard doses fail, the assessment of resuscitative efforts with end-tidal CO2 monitoring and the addition of two new drugs, amiodarone (for refractory ventricular fibrillation) and adenosine (for paroxysmal supraventricular tachycardia). Time will determine the ultimate role of these advancements in the management of cardiac arrest.
Persistent mullerian duct syndrome. Persistent mullerian syndrome is rare. A case of phenotypically normal male with persistent mullerian structures that consisted of a bicornuate uterus, fallopian tubes, and upper third of the vagina is reported. These unusual structures were found in association with bilateral cryptorchidism and a right inguinal hernia, and were diagnosed while repairing the hernia in the neonatal period. The uterus and fallopian tubes were removed via laparotomy when the child was eighteen months old; at the same time a bilateral orchiopexy was performed. To avoid damage to the vas deferens, which lay in closely to the mullerian structures and could not be separated from the vaginal wall, a small segment of the upper third of the vagina was retained. The testicles, although normal on pathologic examination, have shown poor response to hormonal stimulation with human chorionic gonadotropin. Long-term follow-up for these patients is necessary because they have an increased risk of testicular tumors developing.
Vagal modulation of the rate-dependent properties of the atrioventricular node. Vagal effects on atrioventricular (AV) nodal conduction are accentuated by increases in heart rate. To establish the mechanism of these rate-dependent negative dromotropic actions, we studied the properties governing AV nodal adaptation to changes in heart rate in chloralose-anesthetized dogs in the absence and presence of bilateral cervical vagal nerve stimulation (20 Hz, 0.2 msec). Stimulation protocols were applied to evaluate the contributions of changes in AV nodal recovery, facilitation, and fatigue independently of each other. Vagal stimulation slowed AV nodal recovery in a voltage-dependent way, increasing the time constant of recovery (tau r) from 80 +/- 7 to 194 +/- 16 msec (mean +/- SEM, p less than 0.01) at the highest voltage studied. The facilitating effect of a premature (A2) beat was manifested by a leftward shift of the recovery curve (A3H3 versus H2A3) of a subsequent A3 beat. The magnitude of shift depended on the A1A2 coupling interval and was reduced by vagal stimulation at all A1A2 intervals (maximum shift: control, 63 +/- 12 msec; vagus, 24 +/- 11 msec; p less than 0.01). When recovery and facilitation were kept constant, abrupt increases in AV nodal activation rate caused a slow (tau = 75 beats) increase in AH interval (fatigue). Vagal stimulation increased the magnitude of this process (maximum: control, 11 +/- 2 msec; vagus, 27 +/- 3 msec; p less than 0.001), without altering its time course. At activation rates comparable to sinus rhythm in humans, vagal stimulation at an intermediate voltage increased the AH interval by 25 msec. As heart rate increased, vagally induced changes in dynamic processes amplified AH prolongation up to fivefold at maximum rate. The role of vagal changes in individual functional properties depended on heart rate, but slowing of recovery was the single most important factor, constituting over 50% of overall vagal action at rapid rates. We conclude that vagal stimulation alters the ways in which the AV node responds to changes in activation rate and that at rapid rates most of the negative dromotropic action of the vagus is due to changes in the AV nodal response to tachycardia. Alterations in rate-dependent AV nodal properties are a novel and potentially important mechanism through which interventions may affect AV nodal conduction.
Immunotherapy in acute arsenic poisoning. We investigated the use of immunotherapy on the treatment of sodium arsenite toxicity. Female balb/c mice injected with arsanilic acid conjugated to a carrier protein (ovalbumin) were shown to produce antibodies (arsenic reactive serum, ARS) reactive with arsanilic acid and sodium arsenite. Serum was tested for anti-ARS antibodies using a solid phase radioimmunoassay. The antisera bound to ARS conjugated to the synthetic copolymer glutamic acid60 tyrosine30 when diluted as high as 1:4096. Following multiple injections of 100 micrograms of arsanilic acid--ovalbumin compound, mortality on injection with sodium arsenite 0.87 mg/kg i.p. one week later decreased to 0 deaths in 22 pretreated mice vs 9 deaths in 29 untreated mice (31% mortality; p less than .005). No decrease in mortality was noted at higher challenges (1.15 mg/kg) of sodium arsenite. Antisera from pretreated mice was injected 0.1 cc i.p. into 12 week old female balb/c mice followed by an injection of sodium arsenite 0.87 mg/kg i.p. at 10 minutes. Again a protective effect was observed with 0 deaths in 18 mice vs eight deaths in 21 mice (38%; p less than .005). Seventeen additional mice were given an injection of 0.87 mg/kg i.p. of sodium arsenite. After 30 minutes, all mice became symptomatic whereupon antisera 0.1 cc i.p. was given. The one day mortality (2/17, 12%) was possibly lower than the combined control mortality (17/50, 34%; p less than 0.07). There was no change in mortality noted when antisera was administered to mice acutely exposed to 5 mg/kg HgCl2.
Recent advances in etoposide therapy for non-small cell lung cancer. Non-small cell lung cancer (NSCLC) continues to be a major health problem in the US. In 1990, approximately 120,000 new cases will be diagnosed, and the majority of these patients will have either unresectable disease or resected disease that has a relatively low chance of being cured. A variety of chemotherapy treatments have been evaluated in patients with advanced NSCLC. The objective of this review is to summarize the results of the chemotherapy trials in Stage III and IV NSCLC patients.
Systemic preoperative chemotherapy with cisplatin, methotrexate and vinblastine for locally advanced bladder cancer: local tumor response and early followup results. A total of 44 patients with infiltrating, locally advanced bladder cancer (stages T 3a-b, T 4a-b and N+/N0) were treated with the systemic chemotherapy regimen of cisplatin, methotrexate and vinblastine (CMV) in the neoadjuvant setting, of whom 39 were evaluable for response. After planned radical cystectomy and 2 to 3 cycles of chemotherapy no tumor was found on the pathological specimen of 4 patients (10%), the tumor was downstaged in 19 (49%) and no change was observed in 16 (41%). Toxicity included leukopenia in 29 patients (66%), 1 of whom died of granulocytopenic sepsis, nausea and vomiting in 39 (89%) and mild to moderate mucositis in 18 (41%). Median followup is 12 months with a range of 6 to 39 months. Of 32 patients followed for longer than 6 months 6 (19%) experienced progression or recurrence of disease. We conclude that preoperative CMV chemotherapy is effective in inducing downstaging of the tumor, although systemic toxicity limits its use to cautiously selected patients.
Approach to diagnosis of meningitis. Cerebrospinal fluid evaluation. CSF evaluation is the single most important aspect of the laboratory diagnosis of meningitis. Analysis of the CSF abnormalities produced by bacterial, mycobacterial, and fungal infections may greatly facilitate diagnosis and direct initial therapy. Basic studies of CSF that should be performed in all patients with meningitis include measurement of pressure, cell count and white cell differential; determination of glucose and protein levels; Gram's stain; and culture. In bacterial meningitis, Limulus lysate assay and tests to identify bacterial antigens may allow rapid diagnosis. Where there is strong suspicion of tuberculous or fungal meningitis, CSF should also be submitted for acid-fast stain, India ink preparation, and cryptococcal antigen; unless contraindicated by increased intracranial pressure, large volumes (up to 40-50 mL) should be obtained for culture. If a history of residence in the Southwest is elicited, complement-fixing antibodies to Coccidioides immitis should also be ordered. Newer tests based on immunologic methods or gene amplification techniques hold great promise for diagnosis of infections caused by organisms that are difficult to culture or present in small numbers. Despite the great value of lumbar puncture in the diagnosis of meningitis, injudicious use of the procedure may result in death from brain herniation. Lumbar puncture should be avoided if focal neurologic findings suggest concomitant mass lesion, as in brain abscess, and lumbar puncture should be approached with great caution if meningitis is accompanied by evidence of significant intracranial hypertension. Institution of antibiotic therapy for suspected meningitis should not be delayed while neuroradiologic studies are obtained to exclude abscess or while measures are instituted to reduce intracranial pressure.
The health belief model: predicting compliance and dropout in cardiac rehabilitation. We investigated the health belief model and the health locus of control constructs as predictors of group membership (compliers or dropouts) with cardiac rehabilitation and whether they added predictive utility to routinely assessed patient demographics and health behaviors. Questionnaires were completed on entry into the study by 120 patients with coronary artery disease, and by the end of the 6 month program there were 58 compliers and 62 dropouts. Discriminant function analyses were carried out to determine prediction of group membership. The health belief model predicted group membership 64.6% of the time, explaining 5.2% of the variance. Demographics, health behaviors, and health belief model factors accounted for 21.1% of the variance between compliers and total dropouts with group membership correctly predicted 74.4% of the time; avoidable and unavoidable dropout was correctly predicted 84.2% of the time with 56.9% of the variance explained. Health locus of control did not distinguish between compliers and dropouts. The addition of the health belief model provided additional information about compliance with cardiac rehabilitation beyond that explained by demographic and health behavior variables alone, particularly when predicting avoidable/unavoidable dropout.
Complete follow-up and evaluation of a skin cancer screening in Connecticut. On May 21, 1988, 251 persons were screened for skin cancer in New Haven, Connecticut. A total body skin examination was performed on 98% of the participants. On the basis of follow-up of 93% of persons with positive screens for basal cell carcinoma, squamous cell carcinoma, or Bowen's disease, positive predictive values were 43% for basal cell carcinoma, 14% for squamous cell carcinoma, and 50% for Bowen's disease. In the group with atypical nevi, a person with two or more clinically atypical nevi was 16 times more likely to have histologic confirmation than a person with a single clinically atypical nevus (p = 0.003). Eighty persons were screened by both a dermatologist and a dermatology nurse; the crude agreement rate for actinic keratoses was 0.62; for atypical nevi, 0.53; and for BCC, 0.88. Both nurses and physicians overdiagnosed in the screening setting, the nurses more so than the physicians. Of the 128 persons screened who were advised to seek medical follow-up, 16 did not do so despite several reminders; their reasons are discussed.
Doxazosin for the treatment of chronic congestive heart failure: results of a randomized double-blind and placebo-controlled study. In this study we evaluated the effects of once-daily administration of oral doxazosin in patients with chronic congestive heart failure (CHF). After a stabilization period of at least 2 weeks with digitalis and diuretics, 73 patients with chronic CHF were randomized to receive additionally either doxazosin or placebo in double-blind fashion. Patients underwent weekly dose adjustments with increasing doses of doxazosin (1, 2, 4, 8, and 16 mg daily) or placebo for 5 weeks, and 67 were evaluated for 12 additional weeks on maximally tolerated doses of blinded study drugs. Treatment groups were evaluated with respect to symptoms of heart failure, indexes of quality of life and left ventricular function, frequency and type of arrhythmia, adverse events, and mortality rates. Doxazosin (11.9 +/- 0.9 mg) given once daily produced a favorable trend in the investigators' and patients' assessments of symptomatic change. Doxazosin was associated with a significantly higher level of voluntary submaximal exercise and a favorable trend on left ventricular ejection fraction (increase of 9.8% of the baseline value vs 2.7% with placebo; p = NS). During the 3-month steady-dosing period, patients treated with doxazosin had a significant (p less than 0.004) reduction in ventricular arrhythmias and significantly fewer morbid and mortal cardiac events (including episodes of worsening heart failure severe enough to prompt discontinuation of the study, myocardial infarction, and death). Doxazosin was well tolerated, producing no major side effects and only a slightly higher frequency of minor treatment-related side effects compared with placebo (p = NS).
Carbon dioxide laser vaporization of diaphragmatic metastases for cytoreduction of ovarian epithelial cancer. Three patients with International Federation of Gynecology and Obstetrics state IIIC ovarian adenocarcinoma underwent CO2 laser vaporization of large-volume (5-6 cm) and miliary right hemidiaphragmatic metastases at the conclusion of standard debulking surgery to effect optimal cytoreduction. Destruction of diaphragmatic metastases was accomplished rapidly with no added morbidity or blood loss. The hand-held CO2 laser is a useful modality for removal of isolated large- and small-volume diaphragmatic disease, particularly if only the peritoneum is involved, and avoids the morbidity that may accompany entry into the pleural space.
Recombination between two 14-bp homologous sequences as the mechanism for gene deletion in factor IX Seattle 1. Factor IXSeattle 1 is a 10-kb intragenic deletion identified in a family that has hemophilia B. By sequencing across the site of the deletion, we discovered at the deletion junction a 13-bp sequence (5' . . . TAGAA-GTTCACTT . . . 3') that was homologous to two 14-bp sequences 10 kb apart in introns D and F of the normal factor IX gene. The presence of these homologous sequences in two different regions of the normal gene allows us to propose that genetic recombination has occurred between the sequences, resulting in the gene deletion. The precise recombination site was able to be localized to one of 5 bp (5' . . . AGTTC . . . 3') in the middle of the homologous sequences. The exact length of the deletion is 10,000 bp.
Clinical diagnosis of tamponade in Malawi. A consecutive series of 25 Malawian patients with tamponade secondary to tuberculosis were compared to 25 patients with congestive cardiac failure, without pericardial effusion in a retrospective study. More patients with tamponade had an impalpable apex beat (21/1), pulsus paradoxus (13/0), soft heart sounds (13/2), paradoxical rise in jugular venous pressure (6/0), and fewer had a murmur (1/14). All these results are significant (p less than 0.05) by the chi 2 test with Yates' correction. The presence of two or more of these discriminating physical signs has a positive predictive value of 75 per cent, and a negative predictive value of 99.5 per cent for the diagnosis of tamponade. Clinical diagnosis of tamponade by primary health care personnel in Malawi should be possible, and lead to earlier treatment.
Cytologic criteria to distinguish hepatocellular carcinoma from nonneoplastic liver. The authors reviewed a series of fine-needle aspiration biopsy (FNAB) specimens of the liver to identify useful cytologic criteria to distinguish hepatocellular carcinoma (HCC) from nonneoplastic liver. Ten cytologic features were examined in this study: high cellularity, acinar pattern, trabecular pattern, hyperchromasia, pleomorphism, irregularly granular chromatin, uniformly prominent nucleoli, multiple nucleoli, increased nuclear/cytoplasmic ratio, and atypical naked hepatocytic nuclei. These features were examined in a series of 82 FNAB specimens from 52 patients with HCC and 30 patients with nonneoplastic lesions. With the use of a step-wise logistic regression analysis, three features were identified as predictive of HCC: increased nuclear/cytoplasmic ratio (P = 0.001), trabecular pattern (P = 0.002), and atypical naked hepatocytic nuclei (P = 0.03). When these three criteria were used, the sensitivity of diagnosing HCC by FNAB was 100%, and the specificity was 87%.