123rc/medical_text huggingface dataset:
Head and neck paragangliomas: a clinicopathologic study with DNA flow cytometric analysis. A total of 11 head and neck paragangliomas were the subject of pathologic study, including histologic, immunohistochemical, and DNA flow cytometric analyses. We cannot absolutely predict aggressive clinical behavior using histologic parameters alone, but we can use such parameters to segregate patients into low-risk and high-risk groups. Several trends were observed in the current study. Tumors with higher S-phase fractions, G2/M fractions, or aneuploid cell populations tended to behave "aggressively." The presence of sustentacular cells in the primary tumors cannot be used as an absolute indicator of tumor metastatic potential, as two metastatic paragangliomas in this study contained sustentacular cells in both the primary and metastatic lesions. DNA ploidy status cannot be used as an absolute prognostic parameter as the two metastatic tumors were composed of diploid primary and metastatic lesions. The three tumors with aneuploid cell populations showed "aggressive" histologic and clinical features, but the length of the follow-up period for these cases is too limited to draw any conclusions. Although no absolute criteria can be used at present to gauge aggressiveness, close follow-up of these patients is essential, especially if pathologic findings suggest an "aggressive" course (ie, "malignant" histology, higher S-phase fractions, G2/M fractions, aneuploid cell populations, or decreased sustentacular cell density).
The use of flumazenil in a neonate. Side effects of benzodiazepines used during pregnancy are described in a neonate. Recurrent apnea was reversed after administration of flumazenil, a specific antagonist of benzodiazepines.
Efficacy and morbidity of partial laryngectomy and postoperative radiation therapy. In recent years, we have seen increasing use of partial laryngectomies for larger lesions that were previously treated by total laryngectomy. The resultant closer margins have made postoperative radiation therapy an important adjuvant treatment to conservation laryngeal surgery. We review the University of California, Los Angeles, experience with combination partial laryngectomy and postoperative radiation therapy between 1973 and 1987 for treatment of carcinoma of the larynx. Twenty-four such patients who underwent partial laryngectomies and postoperative radiation therapy are examined. Techniques of treatment, complications, and the functional ability of the remaining larynx are discussed. The locoregional control rate at 5 years was 80%. Risk factors associated with an increased risk of recurrence were positive margins, vascular invasion, and extranodal spread. There were no major problems with postoperative wound healing or airway management during the radiation treatment. Vocal and swallowing function were well preserved in most cases. We conclude that combination partial laryngectomy and radiation therapy permits preservation of laryngeal function without serious complications, and therefore is an effective treatment for selected patients with carcinoma of the larynx.
Triggers of transient myocardial ischemia: circadian variation and relation to plaque rupture and coronary thrombosis in stable coronary artery disease. The phenomenon of transient myocardial ischemia is common in patients with stable coronary disease and appears to be due both to increases in myocardial demand and to episodic coronary vasoconstriction. The circadian variation of transient ischemic episodes closely parallels the circadian variation of acute coronary syndromes associated with plaque rupture, such as myocardial infarction and sudden death. These concordant temporal patterns of transient ischemia, myocardial infarction and sudden cardiac death probably represent independent manifestations stemming from the consequences of increased sympathetic activity.
CO2-welded venous anastomosis: enhancement of weld strength with heterologous fibrin glue. The milliwatt CO2 laser was used to perform end-to-end anastomoses in canine jugular veins. There was a high disruption rate (50%) in laser-welded veins (n = 10). Fibrin glue (n = 17), formed from human fresh-frozen plasma, enhanced the weld strength decreasing the disruption rate (18%), resulting in an 82% patency which nearly equaled the contralateral sutured vein patency (93%). The bursting strength was improved with fibrin glue. Transmural necrosis was present initially in all groups but extended for a longer distance in the vessel wall in laser-welded anastomoses. Sutured anastomoses exhibited a greater inflammatory response. In laser-welded anastomoses endothelial cells were not as confluent as in sutured anastomoses by six weeks. Carbon dioxide laser-welded end-to-end vein anastomoses appear to be impractical because they disrupt too easily. However, the addition of heterologous fibrin glue to the weld results in a reasonably strong anastomosis with histologic properties that may be beneficial in vein bypass grafts.
Detection of hepatitis B virus DNA by polymerase chain reaction in plasma of volunteer blood donors negative for hepatitis B surface antigen. Plasma samples from 206 volunteer blood donors were tested for hepatitis B virus (HBV) DNA by dot blot hybridization and polymerase chain reaction (PCR). All donors were negative for hepatitis B surface antigen (HBsAg) and had normal serum alanine aminotransferase levels. None of the 206 plasma samples was positive for HBV DNA by dot blot hybridization assay. However, nine samples were positive for HBV DNA by PCR using two primer pairs specific for surface and core regions. Nine persons received the HBV-DNA-positive plasma, and one developed posttransfusion non-A, non-B hepatitis; the others remained well 6 months later. Therefore, approximately 4% of blood donors in Taiwan have low titers of HBV DNA, and a more sensitive method to screen donors may be needed in the future, although the current serologic test remains the most practical at present.
Hepatic giant cavernous hemangioma with microangiopathic hemolytic anemia and consumption coagulopathy. We describe a case of hepatic giant cavernous hemangioma with both microangiopathic hemolytic anemia (MAHA) and consumption coagulopathy, but without thrombocytopenia, which was completely cured by surgical resection of the tumor. The patient was a 54-yr-old Japanese woman whose chief complaint was right upper abdominal discomfort. Angiography and dynamic computed tomography revealed typical findings of hepatic cavernous hemangioma. The patient also had hematological disorders. At surgery, we performed an atypical right lobectomy to preserve as much normal liver tissue as possible. The patient has been well, with no related complaints or abnormal laboratory findings, 5 yr since her operation. This case indicates that giant cavernous hemangioma of the liver should be considered in the differential diagnosis of MAHA, and if surgical treatment is adequate, hematological abnormalities may be eliminated.
Gonadotroph adenoma of the pituitary mimicking a prolactinoma. In a 41-year-old woman with mild hyperprolactinemia and amenorrhea, preoperative hormonal and neuroradiological findings suggested the diagnosis of a macroprolactinoma. She underwent transsphenoidal surgery since the tumor size had not changed in spite of bromocriptine administration for 5 months. Consequently, this case was diagnosed as a female-type gonadotroph adenoma on the basis of its characteristic ultrastructural features including a honeycomb Golgi complex, even though endocrinological and immunohistochemical findings were not those of a typical gonadotroph adenoma.
The effect of diaper type and overclothing on fecal contamination in day-care centers [published erratum appears in JAMA 1991 Jun 5;265(21):2810] Fecal coliform contamination of environmental surfaces and hands in the day-care center is common. This study evaluated the effect of two diaper types on fecal contamination. Ten rooms in four day-care centers containing 141 children were studied in a prospective, randomized, crossover study. A total of 2946 samples were cultured during the 9-week study. Fecal coliforms were isolated from 307 inanimate objects (15%), 73 toy balls (46%), and 131 hands (17%). The number of contaminated inanimate objects was significantly less in rooms where paper diapers were worn when compared with that in rooms where double cloth diapers with plastic overpants were worn and in rooms where clothes were worn over diapers. Inanimate object cultures had more contamination in rooms in which diarrhea had occurred. Containment of feces by overclothes and diaper type may be important in decreasing transmission of enteric pathogens in day-care environments.
Is thioridazine retinopathy progressive? Relationship of pigmentary changes to visual function. Thioridazine toxicity has been described as a 'progressive chorioretinopathy', but this designation can be misleading. During the first year after thioridazine exposure retinal pigmentation evolves from a granular to a patchy or nummular appearance. However, visual function and the electroretinogram typically improve during this period. Some cases may show chorioretinal atrophy and functional loss many years later, but there is little evidence for ongoing drug-related progression. Late atrophy may represent degeneration of cells that were injured subclinically at the time of initial drug exposure. Although thioridazine toxicity produces an evolving pigmentary disturbance, functional changes must be monitored independently of fundus appearance.
Is baldness a risk factor for coronary artery disease? A review of the literature. A literature search identified eight articles containing data on both baldness and coronary artery disease (CAD). Three of these articles described case-control studies that showed a positive relationship between baldness and CAD when controlling for CAD risk factors. Three other case-control studies showed no such relationship, but these did not control for CAD risk factors. The results of two cohort studies were inconclusive. Insufficient data were available from these studies to analyze possible relationships between baldness and CAD risk factors themselves. Overall, the data reviewed suggest that a small risk of CAD due to baldness may exist, but this risk is smaller than that of well-known CAD risk factors such as smoking and hypertension. Future research should emphasize proper control for age and CAD risk factors.
Surrogate receptor-mediated cellular cytotoxicity against malignant human glioma cells. A method for incorporating palmitate-derivatized antibody molecules into effector cells and the influence of these incorporated antibodies (surrogate receptors) on the lytic potential of peripheral blood lymphocytes is described. This surrogate receptor-mediated cellular cytotoxicity provides a means by which killer cells are directed specifically to the desired target glioma cells. The cytotoxic activity does not require the Fc region of the incorporated antibody molecules and shows more lytic potential than ordinary antibody-dependent cellular cytotoxicity. By complement-mediated cell depletion and Percoll gradient separation, the effector cell populations for surrogate receptor-mediated cellular cytotoxicity are found to be natural killer cells, as in the murine system. This strategy of surrogate receptor incorporation into effector cells may provide not only valuable insights into the mechanism of cell-mediated cytotoxicity, but also a means of generating target-specific effector cells for clinical applications in neurosurgery.
Use of m-[131I]iodobenzylguanidine in the treatment of malignant pheochromocytoma. The efficacy and safety of m-[131I]iodobenzylguanidine ([131I]MIBG) were assessed in 15 patients with malignant pheochromocytomas in a nonrandomized, single arm trial, in which patients were treated with [131I]MIBG (SA, 740 megabequerel/mg) every 3 months. Seven of these patients had bone and soft tissue metastases, 4 had only soft metastases, and 4 had only bone metastases. The follow-up period ranged from 6-54 months; the number of doses ranged from 2-11, with 2.9 (78.4 mCi) to 9.25 gigabequerel (GBq) (250 mCi)/administration and a cumulative activity from 11.1-85.90 GBq (300-2322 mCi). The absorbed cumulative dose in tumors ranged from 12-155 Gy. A beneficial effect of the treatment was observed in 9 patients (60%). No complete remission of the disease was observed. Seven patients died during the study, among whom 4 never responded to the treatment. Seven had hormonal responses (4 complete and 3 partial), with a duration ranging from 5-48 months. Among these patients, 4 relapsed, and 3 died within 3 months. Five patients had partial tumoral responses mainly located in soft tissues and for a duration ranging from 29-54 months. All patients with a hormonal response had objective improvement in clinical status and blood pressure. There was no clear-cut relationship between the cumulative dose and the responses. The main side-effect observed in 1 patient with widespread bone metastases after three doses (12.9 GBq) was a pancytopenia, which resolved after treatment was discontinued. This study suggests that repeated [131I]MIBG treatment could be effective in patients with advanced malignant pheochromocytoma.
Complications of percutaneous abdominal fine-needle biopsy. Review. To determine whether the increasing use of percutaneous fine-needle biopsy of abdominal lesions is associated with an increase in serious complications, the author updated a literature search and evaluated a questionnaire (distributed among selected hospitals in the United States in 1986 and 1987) that followed up a questionnaire distributed in 1983. The updated literature review revealed a total of 24 deaths and 20 needle tract seedings. The updated questionnaire revealed five deaths after 16,381 biopsies (0.031%), whereas the previous questionnaire had shown four deaths after 63,108 biopsies (0.006%). Two similar European questionnaires revealed mortality rates of 0.008% and 0.018%, respectively. Of the total of 33 deaths, 21 involved biopsies of liver lesions; six involved pancreatic biopsies. Seventeen of the 21 deaths after liver biopsies were secondary to hemorrhage; five of the six deaths after pancreatic biopsies were due to pancreatitis. Of the 23 instances of needle tract seeding, 10 occurred after biopsies of pancreatic malignancies. The frequencies of needle tract seeding in the four questionnaires were 0.005%, 0.006%, 0.003%, and 0.009%, respectively. Although infrequent, serious complications may be associated with this procedure. The author makes suggestions that may help minimize them.
Absence of estrogen receptors in dysplastic nevi and malignant melanoma. Benign nevi, dysplastic nevi, and primary and metastatic malignant melanomas were evaluated for the presence of sex hormone binding and estrogen receptor protein. We have confirmed the observation of Ellis et al. that some pigmented lesions possess sex hormone-binding proteins. We could not demonstrate a true estrogen receptor in any benign nevi, dysplastic nevi, primary melanomas, or metastatic melanomas. Thus the ability to bind estrogen or progesterone does not correlate with the presence of a true estrogen receptor. Lack of nuclear estrogen receptors suggests that the influence of estrogen on the pathophysiology of melanoma or of benign melanocytic nevi may not be significant.
Molecular methods to detect the Philadelphia chromosome. The Ph1 chromosome has two molecular subtypes: a bcr-positive seen in CML and some cases of ALL, and the bcr-negative subtype mainly seen in ALL. In CML, because of the restriction of chromosome 22 breakpoints to the bcr, Southern analysis to detect bcr rearrangements also can be used to detect the Ph1 chromosome. In contrast, the translocation breakpoints on the Ph1 chromosome are scattered in ALL, so that other methods such as PFGE and PCR are necessary to detect the Ph1 chromosome. In both CML and ALL, use of these methods to detect molecular abnormalities may be superior to cytogenetics in detecting chromosomal abnormalities. Southern analysis also can be used in CML to map breakpoint locations within the bcr. This may offer prognostic information as to the length of chronic phase, but there is conflicting information as to the validity of this approach. The modified PCR (using cDNA from mRNA) can be used to detect the Ph1 chromosome and to define which of the molecular subtypes are present. The exquisite sensitivity of this method, which is capable of detecting as little as a single abnormal molecule of RNA or DNA, makes it suited for the detection of minimal residual disease in both CML and ALL. This is particularly useful after intensive therapies, such as bone marrow transplantation. Whether these low levels of fusion gene expression are of prognostic significance is still unclear.
Fibrocellular tissue response after percutaneous transluminal coronary angioplasty. An immunocytochemical analysis of the cellular composition. BACKGROUND. Restenosis after initial, successful percutaneous transluminal coronary angioplasty (PTCA) is due to fibrocellular proliferation. METHODS AND RESULTS. The present study focused on the nature of fibrocellular tissue in humans by use of immunocytochemical techniques. Four hearts (five coronary arteries) were investigated; time lapse between PTCA and death varied between 20 days (two arteries) and 1 year 7 months. Proliferating cells stained positive with smooth muscle cell-specific monoclonal antibodies. Cells from early proliferative lesions (20 days) have a phenotypic expression different from cells in "old" lesions. Proliferating cells stained positive with vimentin but were negative with desmin, irrespective of the lesion's age. CONCLUSIONS. The findings indicate a change in actin isoform expression of smooth muscle cells while adapting to a pathological state.
The associated anomalies that determine prognosis in congenital omphaloceles. Cogenital abdominal wall defects such as omphaloceles can be recognized by fetal ultrasonography. To determine whether associated anatomic features may be useful in determining fetal prognosis, a retrospective study was performed over a 5-year period. There were 28 cases of omphalocele; 16 were larger than 5 cm and classified as giant, and the remainder were considered small. Eleven of the 12 infants with small omphaloceles survived with minimal neonatal complications. Ten of the 16 infants with giant omphaloceles died because of associated congenital anomalies. These were congenital heart disease, central nervous system malformations, and diaphragmatic hernias. This review suggests that the prognosis is good when a prenatal diagnosis of giant omphalocele is made and careful fetal ultrasonography, including echocardiography, does not identify heart, central nervous system, or diaphragmatic malformations, even when there is liver herniation into the omphalocele.
An unusual late complication following surgical repair of tetralogy of Fallot. A case is presented of extrusion of right ventricular outflow tract patch material through a mediastino-cutaneous fistula occurring five years after repair of tetralogy of Fallot. The focus of the mediastinal infection was an infected epicardial pacemaker electrode placed at the time of initial surgery. Subsequent echocardiographic studies showed minimal right ventricular outflow tract or pulmonary arterial dilatation, and, with no further surgery, the child is well after two and a half years follow-up.
Nisoldipine--effects on the renin-angiotensin-aldosterone system and catecholamines. Studies in normotensive and hypertensive subjects. We have studied the effects of nisoldipine, a new calcium channel antagonist, on the renin-angiotensin-aldosterone system and on plasma catecholamines in 10 healthy volunteers and in 29 patients with primary essential hypertension. Of these 29 patients, thirteen had normal renin hypertension (NRH), and sixteen had low renin hypertension (LRH). Eight healthy volunteers received placebo. Short-term (24 h) effects were measured in all subjects and long-term (up to 6 months) effects of 10-40 mg nisoldipine daily were monitored in the 29 hypertensive patients. Plasma renin activity (PRA) increased slightly, although this rise was not statistically significant, 1 h after the first dose of nisoldipine in both normotensive subjects and hypertensive patients. After 2 h PRA had returned to the pre-treatment level. No change in PRA was observed after administration of placebo. Plasma angiotensin II (AII) levels showed considerable variation after nisoldipine administration. Plasma aldosterone levels decreased despite the increase in PRA and AII concentrations. However, no concomitant reduction in urinary aldosterone excretion was observed. Plasma noradrenaline levels increased slightly 2-4 h after administration of nisoldipine, and decreased again thereafter, but no changes in plasma adrenaline levels were seen. Nisoldipine had no long-term effects on the renin-angiotensin-aldosterone system or on serum catecholamine levels.
Pivotal role of early and sustained infarct vessel patency in patients with acute myocardial infarction. Thrombolytic therapy in acute myocardial infarction unequivocally has improved short- and long-term mortality. The fundamental goal of therapy for evolving myocardial infarction is early and sustained infarct vessel recanalization. The mechanisms linking an open artery with improved long-term survival and other clinical outcomes are presented with use of data from extensive clinical trials.
Total perinatal wastage. A clarification of priorities. The pregnancy outcome of 16,971 women carrying 17,352 living fetuses after 16 weeks gestation was studied. As well as recording perinatal deaths, all losses before 28 weeks and up to one year after delivery were recorded to give a total perinatal wastage rate of 21.6 per 1000 fetuses alive at 16 weeks compared with a perinatal mortality rate (stillbirths plus early neonatal deaths) of 7.8 per 1000 births. All deaths were then classified according to pathological sub-groups. The concept of auditing perinatal care using perinatal mortality was then compared with that using total perinatal wastage.
Piezoelectric lithotripsy and soft tissue injury. Safety limits in the experimental and clinical setting. Controversy surrounds the capacity of extracorporeal shock wave lithotripsy to cause soft tissue injury. This study examines the influence of different dosages of shock waves on the gall bladder in both humans and an animal model. Sixty one guinea pigs were divided into groups and subjected to different numbers of shock waves (6,000, 24,000, and 48,000) at different frequencies (2.5, 5.0, 10, 20 shock waves per second) and sacrificed at different intervals. Soft tissue damage after lithotripsy seemed to be related to the number of shock waves administered. In addition, repeated administration of low dose lithotripsy (at weekly intervals for six weeks) did not seem to produce a cumulative injury. Finally, in the animals sacrificed one month after receiving high dose lithotripsy, no soft tissue damage was evident, indicating satisfactory healing. Thirty patients were subjected to either high dose (36,000 shock waves) or low dose (6,000 shock waves) lithotripsy 24 hours before elective cholecystectomy. Both macroscopic and microscopic evidence of soft tissue injury were detected in a significantly higher percentage of patients who received a high dose in a single treatment (p less than 0.05). The group who received repeated low dose lithotripsy showed no evidence of cumulative injury. We conclude that low dose lithotripsy produces minimal soft tissue injury and is safe when repeated up to six times at weekly intervals.