123rc/medical_text huggingface dataset:
Deletion of the human retinoblastoma gene in primary leukemias. As an initial step in evaluating the role of tumor suppressor genes in leukemogenesis, we surveyed primary leukemia cells from 130 patients for possible deletion of the retinoblastoma susceptibility (Rb) gene by Southern blot analysis. Two of them clearly showed homozygous deletion of Rb alleles. The first patient was a pre-B acute lymphoid leukemia (ALL) associated with a cytogenetic translocation: t(14;16)(q24;q22). The deletion was located at the 3' portion of the Rb gene, very close to the site of Rb gene deletion recently identified in an ALL cell line. The absence of Rb110 protein was further confirmed by Western blot analysis. The second patient was a chronic myelomonocytic leukemia (CMMoL), terminated in acute blastic transformation. Deletion of the 5' portion of Rb gene was found in leukemic cells in the chronic stage. The results indicated that inactivation of the Rb gene occurred in certain cases of leukemia. Its significance warrants further study.
An early description of slowly progressive aphasia. Slowly progressive aphasia without generalized dementia has become an important issue of present-day neuropsychological research. Historically, credit for the first description is usually given to Pick. Another German-speaking author who has published a vivid description of a pertinent cases is Pick's contemporary, Max Rosenfeld. This author has also observed a patient with slowly progressive spatial disorientation and visual recognition deficit, and he has discussed these patients in a remarkably modern way in the context of partial atrophy of the brain.
In vivo assessment of shock-wave pressures. Implication for biliary lithotripsy. During extracorporeal shock-wave lithotripsy, the pressure profile, which is generated by the lithotriptor, determines the risk of tissue damage. In the present study, the pressure distribution of a lithotriptor (Lithostar; Siemens A.G., Erlangen, Federal Republic of Germany) was investigated in 10 pigs, five of which had gallstones surgically implanted into the gallbladder. The in vivo values were compared with in vitro data. Measurements were carried out along the shock-wave transmission path at the focus within the gallbladder, the adjacent liver, the diaphragmatic surface of the right lung, and the shock-wave exit site from the skin. Interposition of ribs did not cause a significant decrease in focal positive pressure. However, a gallstone positioned in the focus caused a 30%-65% reduction in pressure, recorded immediately behind the stone. Pressures obtained in vivo were always 15%-25% lower than those measured in vitro. The spatial distributions of the positive pressure in vivo and in vitro were almost identical. There was a high correlation between the pressures in vitro and in vivo (r = 0.88; P less than or equal to 0.01). This justifies assessment of shock-wave energies generated during biliary lithotripsy by extrapolation of in vitro data. It is concluded that it is possible to characterize different lithotriptors by in vitro pressure profile measurements.
Hip pain in late pregnancy. Hip pain in late pregnancy is quite common, and its etiology is rarely established unless acute demineralization occurs. We measured the bone mineral content of both hips in 26 women within 48 hours of delivery. Twelve of 36 densities (33%) were decreased in a group with severe pain when compared to 12 of 120 decreased densities (10%) in the remaining patients (P less than .05). Those data suggest that severe hip pain may be related to a decrease in bone mineral content.
Concomitant cisplatin chemotherapy and radiotherapy in advanced mucosal squamous cell carcinoma of the head and neck. Long-term results of the Radiation Therapy Oncology Group study 81-17. One hundred twenty-four eligible patients with advanced mucosal squamous cell carcinoma of the head and neck were entered into a pilot study of concomitant cisplatin (100 mg/m2 given every 3 weeks for three doses) and standard irradiation. The initial complete response (CR) was 71% with an additional two cases salvaged by surgery for an overall 73% CR. When no keratin was identified in the histologic specimen (41 patients) the CR was 90%. The nasopharynx showed the best CR (89%) among the sites. At 4 years after treatment, the estimated locoregional tumor control rate was 43% and the survival, 34%. When no keratin was present in the specimen, the estimated locoregional control of tumor was superior (56% versus 38% with keratin identified, P = 0.02) and the estimated survival was also superior (48% versus 26%, P = 0.008). Acute treatment-related toxicities included one death due to renal damage and two patients with life-threatening renal damage. The delivery of radiotherapy was not altered. Late toxicity included necrosis -3%, fibrosis -4%, and one fistula. The results of this study justify a randomized trial for the comparison of this combination of cisplatin and radiotherapy versus radiotherapy alone in advanced mucosal carcinomas of the head and neck.
Replication patterns of the fragile X in heterozygous carriers: analysis by a BrdUrd antibody method. The replication status of the fragile X chromosomes was studied in short-term cultures of lymphocytes from six female heterozygous carriers. The fragile X was induced by adding 0.1 microM fluorodeoxyuridine during the last 24 h of culturing. The replication status of the X chromosomes was studied using a bromodeoxyuridine (BrdUrd) antibody method. BrdUrd was added (1) at a final concentration of 0.2 micrograms/ml during the early S phase of chromosome replication (16-10 h before harvest), (2) at 0.2 microgram/ml during the late S phase (the last 6 h of culturing), (3) at 20 micrograms/ml during the early S phase, and (4) at 20 micrograms/ml during the late S phase. BrdUrd that was incorporated into replicating chromosomes was detected by using a nuclease and BrdUrd monoclonal antibody. The frequency of the fragile X was reduced by BrdUrd treatment. The degree of reduction was more severe in the 20 micrograms/ml than in the 0.2 microgram/ml series and was more severe with late S than with early S treatment. Of the early- and late-replicating fragile X chromosomes, those which were actively replicating during a BrdUrd treatment were more reduced than the others. Thus, the average rate of early and late S treatment with 0.2 microgram BrdUrd/ml was assumed to be the closest reflection of the situation in vivo. There was no correlation between the average rate of the early replicating, active fragile X and the intelligence of the heterozygous carriers studied.
Surgical treatment of cardiac myxomas: long-term results. Between 1965 and 1988, 22 patients underwent 24 operations for cardiac myxomas. Two patients had the complex myxoma syndrome. Mitral valve replacement was required at initial operation in 2 patients. One patient died perioperatively, and 5 others died subsequently. The 16 surviving patients recently underwent evaluation at a mean duration of 9 years after operation. Ten are asymptomatic and 6 have New York Heart Association class II symptoms. Nine patients continue to be employed. Eleven are in sinus rhythm, 3 have permanent pacemakers, and 2 have chronic atrial arrhythmias. Echocardiography showed atrioventricular valve insufficiency in 3 patients and reduced contractility in 4, but no new tumor recurrences. The long-term prognosis of this relatively large group of patients with cardiac myxomas has been good. Patients without the complex myxoma syndrome had no recurrence, whereas 2 patients did require reoperation for mitral valve replacement. Long-term disability and chronic arrhythmias have been infrequent, and functional status and employability of these patients have been very good.
The use of probenecid as a chemoprotector against cisplatin nephrotoxicity. Probenecid inhibits cisplatin (CP) secretion in humans and protects against CP-induced nephrotoxicity in rats. The authors conducted a Phase I trial of escalating doses of CP using probenecid as a chemoprotector. Fifty-four courses of CP at doses ranging from 100 to 160 mg/m2 were given by 24-hour infusion to 36 patients. There was no renal impairment at any dose. Ototoxicity, however, became the dose-limiting toxicity; 14 patients experienced a 20 or greater decibel (dB) loss. Seven percent of courses were associated with a leukocyte count of less than 1.5 x 10/microliters, and 19% with a platelet count of less than 50 x 10(3)/microliters. Only three patients developed neurotoxicity. Correlating pharmacokinetic data and toxicity, the authors found that high cumulative dose, area under the curve (AUC) for unbound platinum, and cumulative AUC were associated with ototoxicity and peripheral neuropathy. It was concluded that probenecid may protect against CP nephrotoxicity and warrants further investigation. Its unique mechanism of action and lack of toxicity make it ideal to combine with other chemoprotectors.
Treatment of metastatic prostate cancer of the spine. There is a wide spectrum of presentations for prostate cancer metastatic to the spine. Important factors are the patient's age and general health; the extent and location of spinal involvement; the patient's neurologic status and degree of pain; the relative contribution of a blastic or lytic response; and the experience and training of the spinal surgeon, medical oncologist, and radiation oncologist. The spine is both a weight-bearing structure and a housing for the spinal cord, and failure to consider both functions may lead to unsatisfactory treatment results. Treatment options include hormonal therapy, inhibitors of bone metabolism, glucocorticoid therapy, radiotherapy, halo-vest, surgical debridement, decompression and stabilization, and appropriate pain management and support. One must not lose sight of the fact that the goals are palliation and that ultimate demise is unavoidable in patients with metastatic prostate cancer.
MYC rearrangement and translocations involving band 8q24 in diffuse large cell lymphomas. The configuration of the MYC gene in diffuse large cell lymphomas (DLCL) with translocations involving band 8q24 [t(8q24)] has not been systematically studied. We collected cytogenetic and clinical data on 171 consecutive cases of DLCL, including cleaved, noncleaved, and immunoblastic types, of which 96 had DNA available and 124 had abnormal karyotypes. The cases with DNA available were evaluated for MYC rearrangement (MYC-R) by Southern hybridization of EcoRI-digested tumor DNA using an exon-1 probe, a combination of probe and enzyme known to detect over 85% of breaks in sporadic Burkitt's lymphoma. In cases studied at diagnosis, MYC-R, t(8;14)(q24;q32), or other t(8q24) were not prognostically significant. Among the 124 cases with karyotypic abnormalities, seropositivity for human immunodeficiency virus was significantly more common in cases with a t(8q24) (72%) than in cases without it (9%) (P less than .05). Of the four cases with an MYC -R, two had a t(8;14), one had a t(7;8;14)(p15;q24;q32), and one had a t(8;?)(q24;?) and a del(8)(q24). In the three previous cases with translocations involving 8q24 and 14q32, comigration of the rearranged MYC band with either the J region or the switch-mu region of the Ig heavy chain gene could not be demonstrated, leaving the 14q32 breakpoint undefined at the molecular level. Among the remaining 72 cases where both an abnormal karyotype and molecular data were available, 11 had a t(8q24), either t(8;14) or t(8;22)(q24;q11), in the absence of an MYC-R. In these cases, the 8q24 break was presumably located outside of the EcoRI MYC fragment. All 15 cases with a t(8q24) were also screened for point mutations in the PvuII site in the first exon of MYC; two cases that were not MYC-R showed loss of this restriction site. These results indicate that in most DLCL with t(8;14) or other t(8q24), the 8q24 breakpoint lies away from the MYC gene; in a minority of these cases, point mutations in regulatory noncoding regions were detected.
Reliability of colposcopy and directed punch biopsy A group of 118 women underwent laser cone biopsy. Data were collected routinely on proforma case notes and entered into a computerized database. The histology of the cone biopsies was compared with that of previous, colposcopically directed punch biopsies, with the cytology of smears taken in the clinic and with the colposcopic diagnosis. The punch biopsy had a 54% false negative rate and neither of the two microinvasive carcinomas biopsied in this way were detected by the biopsy. Ten of 24 women with negative punch biopsies had CIN III in the cone. When the punch biopsy showed CIN II or worse, the cone biopsy confirmed the presence of CIN in 86%. There was some evidence of false negative cone biopsies. The data suggest that management should not be based solely upon the punch biopsy result but should include consideration of the cytology and colposcopy findings. Excisional methods of treatment are more likely to reveal early invasion and adenocarcinoma-in-situ.
Characterization of the in vitro maturation of monocytes and the susceptibility to HIV infection. The in vitro maturation of peripheral blood monocytes to macrophages can be followed morphologically, and by measurement of cell surface antigens (CD4, HLA-DR, and FcR III) and lysozyme production. We used these markers to correlate monocyte maturation with susceptibility to human immunodeficiency virus (HIV) infection. Maturation of peripheral blood monocytes is associated with a decrease in membrane CD4, while HLA-DR and FcR III expression increase along with lysozyme secretion. Cells at all stages of maturation were susceptible to HIV infection, even mature macrophages without CD4 detectably by immunofluorescent staining. Maximal replication was observed in 7-day-old cells.
Are cystgastrostomy and cystjejunostomy equivalent operations for pancreatic pseudocysts? To compare the effectiveness of cystgastrostomy and cystjejunostomy for treatment of pancreatic pseudocysts, 39 patients with cystgastrostomy were compared to 59 patients with cystjejunostomy. The groups were comparable in age, sex, cause of pancreatitis, pseudocyst location, symptoms, and preoperative serum amylase level. Cysts treated with cystgastrostomy were larger (mean diameter, 11.1 +/- 0.9 cm) than cysts treated by cystjejunostomy (mean diameter, 6.7 +/- 0.7 cm) (p less than 0.05). Mean duration of surgery was 148 +/- 11 minutes for cystgastrostomy versus 265 +/- 15 minutes for cystjejunostomy (p less than 0.05). Mean blood loss was 397 +/- 82 ml for cystgastrostomy versus 703 +/- 80 ml for cystjejunostomy (p less than 0.05) Mean intraoperative fluid requirements were 2640 +/- 313 ml for cystgastrostomy and 4403 +/- 362 ml for cystjejunostomy (p less than 0.05). Cyst recurrence was 10% for cystgastrostomy versus 7% for cystgastrostomy. Postoperative gastrointestinal bleeding occurred in 8% of patients with cystgastrostomy and in 2% of patients with cystjejunostomy. Infection problems with cystjejunostomy included two wound infections and one case of septicemia; infection problems with cystjejunostomy included five intraabdominal abscesses, two wound infections, and one case of pneumonia. Two patients died with cystgastrostomy (both from gastrointestinal bleeding); two patients died with cystjejunostomy (one from intraabdominal sepsis and one from pulmonary embolus). Cystgastrostomy was used for significantly larger pseudocysts and was associated with significantly less blood loss and operating time than cystjejunostomy (p less than 0.05). Morbidity and mortality from cystgastrostomy and cystjejunostomy were comparable, although gastrointestinal bleeding was more common with cystgastrostomy and intraabdominal abscess was more common with cystjejunostomy. Since cystgastrostomy can usually be performed more quickly and with less blood loss, it should be considered whenever anatomically feasible.
'Locked-in syndrome' for 27 years following a viral illness: clinical and pathologic findings. We describe a man who, after a presumed encephalitic illness, was "locked-in" for 27 years. His CT and autopsy findings showed atrophy of the brainstem and a cystic lesion at the base of the pons. He survived longer than most other patients in a similar state.
Mammographic follow-up of low-suspicion lesions: compliance rate and diagnostic yield. All recommendations for mammographic follow-up of low-suspicion lesions seen at mammography during a 6-month period were reviewed to establish compliance rate and eventual outcome. One hundred forty-four of 2,650 mammograms (5%) showed minimal abnormalities that warranted short-term and periodic mammographic follow-up. Rates of compliance at 4 months and at 1, 2, and 3 years were 88%, 71%, 60%, and 47%, respectively. Progressive mammographic change was found in 10 patients, only one of whom had a carcinoma. It was concluded that mammographic follow-up of low-suspicion lesions is a reasonable alternative to surgical biopsy, although patient compliance remains a significant problem.
Deferoxamine fails to improve postischemic cardiac function in hypertrophied hearts. Myocardial hypertrophy is a well-recognized risk factor in congenital cardiac surgery. Hypertrophied hearts have been demonstrated to have an increased vulnerability to ischemia/reperfusion injury. We studied the effects of the iron chelator and hydroxyl radical scavenger deferoxamine given during early reperfusion in a model of isolated retroperfused rabbit hearts made hypertrophic by aortic banding early in life (1 week of age). The rabbits were studied at 6-8 weeks of age, and the hearts were subjected to 30 minutes of 37 degrees C ischemia followed by 30 minutes of reperfusion. Postischemic recovery of isovolumic developed pressure was measured by using an intracavitary balloon in both the untreated (n = 6) and the deferoxamine-treated (n = 6) groups and compared with normal age-matched controls. Deferoxamine (50 mumol/kg) was given to one group with the hypertrophied hearts during the first 10 minutes of reperfusion. The left ventricular weight/body weight ratio in the hypertrophied hearts was 2.9 +/- 0.4 x 10(-3) (n = 14) versus 2.0 +/- 0.1 x 10(-3) in the age-matched controls (p less than 0.05). Postischemic peak developed pressure recovered to 102 +/- 6% of the preischemic value in the normal hearts after 30 minutes of reperfusion compared with 75 +/- 5% for the untreated and 71 +/- 4% for the deferoxamine-treated hearts (p less than 0.05 vs. control). We conclude that chronic hypertrophy from early in life leads to increased susceptibility to ischemia and that the iron chelator deferoxamine is not effective in preventing the injury of reperfusion in hypertrophied hearts.
Prevalence and prognostic significance of exercise-induced ventricular arrhythmias after coronary artery bypass grafting. Exercise-induced ventricular arrhythmias occur often after coronary artery bypass grafting (CABG), but their prognostic significance is unknown. Two hundred patients examined by exercise electrocardiography and cardiac catheterization (including left ventriculography, bypass graft and native coronary artery angiography) before and 3 months after CABG were prospectively followed up. Exercise-induced ventricular arrhythmias occurred more often after (49 of 200 patients, 24.5%) than before (32 of 200 patients, 16.0%) CABG (p less than 0.05). There were no differences between the patients with and without ventricular arrhythmias in the prevalence of graft patency (79 vs 80%) or the postoperative ejection fraction (57 +/- 9 vs 57 +/- 12%). Ten cardiac deaths occurred during the mean follow-up time of 61 +/- 19 months, 8 of which were witnessed sudden cardiac deaths. All cardiac deaths occurred in patients who did not have exercise-induced ventricular arrhythmias after CABG. The postoperative ejection fraction was lower in the cardiac death patients (42 +/- 16%) than in the survivors (58 +/- 10%) (p less than 0.01). No other clinical or angiographic variable predicted the occurrence of cardiac death. Thus, the prevalence of exercise-induced ventricular arrhythmias increases after CABG, but the occurrence of ventricular arrhythmias does not indicate an increased risk of cardiac death.
Hypertension, endothelium, and cardiovascular risk factors. The functions of the endothelium and the effects of hypertension, atherosclerosis, and diabetes on the endothelium are reviewed. The endothelium affects vascular tone by releasing vasodilators and modulating the effects of vasoactive substances such as catecholamines, bradykinin, serotonin, and angiotensin II. Relaxation of vascular smooth muscle depends upon a functionally intact endothelium and the release of the endothelium-derived relaxing factor nitric oxide. Endothelial cells also appear to release a hyperpolarizing factor that relaxes smooth muscle through activation of the sodium-potassium pump, and of the endothelium-dependent contracting factors. Similarities are found in the vascular injury resulting from hypertension, atherosclerosis, and diabetes. When these risk factors coexist, they can act synergistically and magnify the vascular injury. The endothelium appears to be one of the major targets for these forms of injury. Future therapeutic strategies will focus on ways to prevent, arrest, or reverse endothelial injury.
A denaturated venous homograft as an alternative material for shunts and other reconstructions in congenital cardiac surgery. A human venous homograft "Varivas R", in clinical use for 10 years for vascular access loops and femoropopliteal bypasses, has been used since December 1985 as a material for aortopulmonary shunts and other reconstructive procedures in congenital heart surgery. For this purpose vein segments 5 cm length, varying in diameter from 4 up to 10 mm by steps of 1 mm, were obtained. Our experience with Varivas is limited to 59 patients. Of 47 infants, 18 received a left, and 25 a right sided aortopulmonary shunt, 9 had bilateral aortopulmonary shunts, 2 right ventricle pulmonary conduits, 1 a pulmonary-pulmonary conduit, 3 interrupted aortic arch reconstructions and 4 a central aortopulmonary shunt, 1 with confluence reconstruction, 3 recidives of coarctation a patch repair. Among 11 adults 6 received coronary bypass and 6 others vascular reconstructions. In contrast to other artificial graft materials, the vein material offers easy manipulation similar to the daily routine of handling fresh vein material offers easy manipulation similar to the daily routine of handling fresh vein grafts in coronary surgery. The appropriate diameter sizes match better the infants anatomy, without the risk of kinking and/or anastomosis displacement. Peroperatively it was possible to confirm patency by electromagnetic flow measurement and the postoperative examinations were done by colour Doppler echocardiography. We had to reoperate upon 4 infants because of early thrombosis; on 1 infant for stenosis of the graft and on another 5 for late thrombosis. In an attempt to extend the indications for "inoperable" pulmonary hypoplasia/atresia we were not able to keep the shunt open in 4 infants.
Endophthalmitis after placement of a Molteno implant. I report a case of early postoperative endophthalmitis following placement of a Molteno implant. Excellent results were obtained by immediate removal of the implant and surgical management of the infection, followed by replacement of the implant.