123rc/medical_text huggingface dataset:
Differential diagnosis of sclerosing cholangiocarcinomas of the common hepatic duct (Klatskin tumors). Although it is recognized that some other lesion may be the cause, a presumptive diagnosis of Klatskin tumor is usually made when a focal stenotic lesion of the common hepatic duct is seen on a cholangiogram of a jaundiced patient. Biopsy is so often nondiagnostic that decisions about therapy are usually made on the basis of the imaging tests and lack of evidence for some other disease. Because the accuracy and consequences of this strategy have never been tested, we contrasted the preoperative diagnosis of Klatskin tumor with the final diagnosis in 98 consecutive patients treated from 1985 to 1990. Preoperative investigations included ultrasound and computed tomographic scans, percutaneous transhepatic cholangiography, endoscopic retrograde cholangiopancreatography, and angiography. Sclerosing cholangiocarcinomas of the bile duct were correctly diagnosed in 68 cases. The final diagnosis was other than a sclerosing adenocarcinoma in 30 (31%) cases. There were 5 papillary bile duct carcinomas, 12 gallbladder carcinomas invading the bile duct, 5 metastatic tumors to the bile duct, 2 cases of Mirizzi syndrome, 3 granulomas, and 3 cases of idiopathic benign focal stenosis. Patients with papillary adenocarcinomas had an extensive filling defect of the duct, which was often thought to be unresectable. However, four of these five lesions could be completely excised, and the tumor was confined to the duct wall in all four. The outcome of surgical treatment of the other eight patients with benign lesions was good in most cases. These findings demonstrate the pitfalls of assuming that a focal stenosis of the hepatic duct represents a sclerosing adenocarcinoma. The diagnosis is much less specific than is generally thought, so there is considerable opportunity for mismanaging such patients.
Improving diagnostic accuracy of cervical metastases with computed tomography and magnetic resonance imaging. Elective neck dissection in patients with head and neck cancer continues to be controversial. The management of these patients would be greatly facilitated by improvements in predicting cervical metastases. Recent investigations have suggested that computed tomography and magnetic resonance imaging are more sensitive in detecting cervical metastases than physical examination. The Department of Otolaryngology at the Ohio State University Hospitals, Columbus, undertook a prospective study to compare the preoperative sensitivities of physical examination, computed tomography, and magnetic resonance imaging with pathologic findings in 27 patients undergoing neck dissections for head and neck cancer. The results indicate that computed tomography and magnetic resonance imaging were more sensitive (84% and 92%, respectively) than physical examination (75%), although the results did not achieve statistical significance. The sensitivity of combined computed tomography and magnetic resonance imaging was 90%.
Multiple primary bronchogenic carcinomas: treatment and follow-up. A second primary bronchogenic carcinoma subsequently developed 8 to 156 months later in 19 patients who underwent curative resection of primary bronchogenic carcinomas. The second primary tumor was treated by surgical resection in 9 patients, 3 patients' tumors were considered unresectable, and the remaining 7 patients, despite having potentially resectable tumors, did not undergo resection because of insufficient pulmonary reserve or unwillingness to undergo resection. Actuarial life-table analysis of survival for the 9 patients who underwent resection showed a median survival time of 110.3 months compared with 19 months for the group with unresected but resectable tumors and 10.5 months for the group with unresectable tumors. There was no operative mortality in the group with resected tumors. We conclude that in patients in whom a second primary carcinoma of the lung develops, surgical resection prolongs survival and can be performed with a low operative mortality.
Computerized identification of pathologic duodenogastric reflux using 24-hour gastric pH monitoring. Duodenogastric reflux is a naturally occurring sporadic event, the incidence, occurrence, and detrimental effects of which have been difficult to assess. The reliability of 24-hour gastric pH monitoring to detect duodenogastric reflux was studied. Central to the use of pH monitoring for this purpose is confidence in its ability to measure and display pH data in a way that reflects changes in the gastric pH environment with sufficient sensitivity. To test this the gastric pH of 10 dogs was measured in the fasting state, after feeding, and after pentagastrin stimulation. The antrum was more alkaline in the fasting state (p less than 0.01) and the display of data by frequency distribution graph was sensitive enough to reflect induced pH changes. To test the consistency of gastric pH at a given position, simultaneous 24-hour gastric monitoring was performed in 12 normal subjects with two probes placed at either 5 or 10 cm below the lower esophageal sphincter. Only at the 5-cm position did the two probes read within 1 pH unit of each other more than 90% of the time. Based on these principles, gastric pH monitoring was performed 5 cm below the lower esophageal sphincter in 30 normal subjects and 11 patients, fulfilling Ritchie's clinical criteria for pathologic duodenogastric reflux. The data obtained was arranged into 71 variables and subjected to discriminant analysis. Sixteen variables were identified, each with a corresponding coefficient to be used as a multiplier to derive a score. A score of more than +2.2 indicated a high probability of pathologic duodenogastric reflux. The test was applied to a validation population consisting of 10 additional normal subjects and 10 patients meeting Ritchie's criteria. All normal subjects had a normal score and all but one (90%) of the patients had an abnormal score. When compared to O-diisopropyl iminodiacetic acid (DISIDA) scintigraphy in another group of 22 normal subjects and 60 patients, 24-hour gastric pH monitoring was superior in the detection of pathologic duodenogastric reflux. The study shows how the application of computer technology can be used to diagnose pathologic duodenogastric reflux in patients with complex foregut complaints.
Three-dimensional reconstructed MR imaging of the inner ear. The three-dimensional Fourier transform fast imaging with steady precession (FISP) technique was used to obtain high-resolution magnetic resonance (MR) images of the temporal bone region and to generate three-dimensional reconstructed images of the inner ear. The three-dimensional reconstructed images of the inner ear were directly synthesized from two-dimensional images of the temporal bone region by means of an external processing computer. With use of three-dimensional reconstructed images and stereoscopic observations, structures inside the temporal bone region and the positional relationship among them were easily recognized. These structures are difficult to demonstrate with two-dimensional images. This three-dimensional method was also shown to be useful for recognition of disease and anatomic malformations in the temporal bone region.
Fetal imaging in the skeletal dysplasias. Second-trimester diagnosis of fetal skeletal dysplasia is becoming increasingly common. By careful examination of the fetus for skeletal mineralization, shape and size of long bones and cranium, and abnormalities of other organ systems, a definitive diagnosis can often be achieved by ultrasound. Fetal radiography is very helpful in giving more information about bone shape and mineralization as well as in confirming the diagnosis. Subsequent obstetric management should be dictated by the natural history of the disease, the parents' wishes, and the gestational age at diagnosis. Because many of these disorders have a high recurrence risk, genetic counseling and follow-up are an important part of the management of these patients.
Vulvar condylomas and squamous vestibular micropapilloma. Differences in appearance and response to treatment. A study of 37 women with typical condylomas and so-called squamous micropapilloma was undertaken to determine their response to systemic interferon and/or podophyllin treatment. Thirty lesions were classified as condylomas and 9 as squamous micropapillomas; two women had both lesions. Twenty-six (87%) of 30 condylomas responded, whereas only 1 (11%) of the 9 cases of micropapillomatosis showed a partial response (P less than .001) to podophyllin and/or interferon. Twenty-six biopsies from condylomas in which sufficient DNA was available for analysis contained human papillomavirus (HPV) DNA sequences that hybridized to an HPV 6 + 16 probe mix under nonstringent conditions. In contrast, HPV DNA sequences could not be detected in any of the nine cases of micropapillomatosis. Immunoperoxidase studies performed on these lesions failed to demonstrate viral capsid antigen. Thus, despite certain similarities in the clinical presentation and microscopic features of condylomas and squamous micropapillomas, it is not clear at present whether micropapillomas are HPV-related lesions.
Interventional radiology of the biliary tract. Metallic stents. Biliary metallic stents were placed in 18 patients with bile duct obstruction. Six patients received Gianturco stents and 14 Wall-stents. Results of these tests are discussed.
Carotid-cavernous sinus fistula associated with a primitive trigeminal artery. Carotid-cavernous sinus fistulas are not rare, but they have never been reported in association with persistent primitive trigeminal artery. We recently encountered such a case. The Jaeger-Hamby procedure was employed, with mandatory occlusion of the primitive trigeminal artery.
Combination therapy for anaplastic giant cell thyroid carcinoma. Since 1981, 20 patients with anaplastic giant cell carcinoma of the thyroid have been prospectively treated according to a combination regimen of chemotherapy and external beam radiation therapy. Two types of chemotherapy were used every 4 weeks, depending on the patient's age. For those younger than 65 years, a combination of doxorubicin (60 mg/m2) and cisplatin (90 mg/m2) was given, and for older patients mitoxantrone (14 mg/m2) was used. Radiotherapy was carried out between Day 10 and Day 20 of the first four cycles of chemotherapy. It delivered 17.5 Gy in 7 fractions to the neck and the superior mediastinum. Survival exceeding 20 months was observed in three patients. Complete neck tumor response was observed in five patients, among whom four had undergone previous operations. No response was seen in distant metastases, which were the cause of death in 14 patients. These treatment modalities are effective in some patients, both in terms of survival and of local control, avoiding death from local invasion. Gross tumor resection should be performed whenever possible but should not delay the commencement of this protocol. Toxicity was high and remains the main limiting factor.
Fatal embolization of intestinal contents through a duodenocaval fistula. Embolization of intestinal contents to the lung is an exceedingly rare event, which to our knowledge, has never been reported as a cause of death. Equally rare is duodenocaval fistula resulting from a penetrating duodenal peptic ulcer. We present the case of a 51-year-old man whose duodenal ulcer led to a fistulous tract with the inferior vena cava and subsequently to progressive pulmonary embolization of intestinal contents, ultimately resulting in death from respiratory failure.
Electrophysiologic characteristics of manifest and latent retrograde conduction in dogs. Atrioventricular (AV) nodal reentry requires intact retrograde ventriculoatrial (VA) conduction. The purpose of this study was to assess the contribution of various pacing and pharmacologic techniques to uncover VA conduction during apparent unidirectional VA block, and to evaluate the role of several biologic and electrophysiologic factors in concealment of retrograde conduction. Forty healthy dogs underwent catheter-electrophysiologic studies of AV and VA conduction. Group I (20 animals) had intact VA conduction. Group II (six animals) had VA dissociation with ventricular pacing initiated during sinus rhythm, but the presence of VA conduction was confirmed by isoproterenol infusion or by premature ventricular stimulation. In group III (14 animals), the above techniques failed to uncover VA conduction. Eight of 14 group III animals underwent thoracotomy and crushing or freezing of the sinoatrial (SA) node. Ventricular pacing initiated during sinus standstill was associated with 1:1 VA conduction in each experiment. VA conduction time and retrograde Wenckebach cycle length, both in the baseline state and during isoproterenol infusion, were significantly longer in the eight animals in group III than in those in group I. Age, gender, weight, breed, sinus cycle length, and anterograde AV conduction properties were not significantly different between groups I, II, and III. The data suggest that (1) in normal dogs, complete unidirectional VA block probably does not exist; (2) in the presence of anterograde input to the AV node, even sophisticated pacing and pharmacologic maneuvers may fail to uncover the presence of VA conduction; (3) although anterograde input is essential for concealment of VA conduction, the phenomenon is more closely associated with depressed retrograde than with anterograde AV nodal characteristics.
Effect of dietary calcium on colon carcinogenesis induced by a single injection of 1,2-dimethylhydrazine in rats. The purpose of this study was to determine if high levels of dietary calcium could inhibit the induction of colon tumors in rats injected with a single dose of 1,2-dimethylhydrazine (DMH). Rats were given a single subcutaneous injection of DMH (200 mg/kg body weight) 2 wk before they were fed purified diets containing 5% fat and four different levels of calcium (as calcium gluconate). After 8 mo, the following incidences of colon tumors (total) were seen: 0.2% Ca, 56%; 0.5% Ca [National Academy of Sciences/National Research Council (NAS/NRC) recommended level], 75%; 1.0% Ca, 61%; 2.0% Ca, 41%. Thus, rats fed calcium at levels above or below the NAS/NRC recommendation had lower tumor incidences. The total tumor incidence and the incidence of adenocarcinomas (with or without invasion) were not significantly affected by calcium, but the incidences of benign adenomatous polyps and of distal colon tumors were significantly affected. Autoradiographic examination of [3H]thymidine-treated rats revealed that the level of calcium did not significantly alter the cell kinetic indices in the distal colon. In the proximal colon, however, the 0.2% Ca group had a significantly larger proliferative zone, with significantly more labeled cells present at the bottom of the colon crypt. Mineral analysis of tibias and serum samples revealed that rats fed higher levels of calcium had lower bone Fe and serum Mg contents, but no significant trends were seen for Ca, P, Zn or Cu. Therefore, increasing or decreasing the calcium content above or below the NAS/NRC recommendation (supplemented to low fat diets) during the promotional phase of colon carcinogenesis altered the tumor incidence, but the effect was confined to the distal colon and to benign adenomatous polyps.
Failure of hepatitis B immunization in liver transplant recipients: results of a prospective trial. Twenty patients with advanced liver disease, in need of transplantation, were given three injections of 20 micrograms and three injections of 40 micrograms hepatitis B vaccine to see if an antibody response could be obtained. Only 20% of patients developed measurable anti-HBs. One who failed to develop anti-HBs developed chronic hepatitis B after exposure to her infected sexual partner. Type of liver disease in the native liver, age, sex, sexual preference, timing of immunization (before or after transplantation), and dosage of hepatitis B vaccine did not seem to explain the lack of immunologic response to hepatitis B vaccine. It is presumed that immunosuppression, both from the underlying disease and from immunosuppressive medications, best explains our findings. Liver transplantation patients infrequently benefit from hepatitis B vaccine. It is possible that other vaccines given to prevent viral and bacterial illness may also fail to elicit immunologic response in such patients.
The effect of Ca and Mg supplementation and the role of the opioidergic system on the development of DOCA-salt hypertension. The effect of calcium and magnesium supplementation and the role of opioidergic system was examined in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. The rats were divided into four groups receiving standard laboratory rat diet (control group; n = 9); a calcium-rich diet with 2% CaCl2 added (Ca-group; n = 12); a magnesium-rich diet with 0.5% MgO added (Mg-group; n = 11); and a calcium and magnesium-rich diet with 2% CaCl2 and 0.5% MgO added (Ca/Mg-group; n = 11); each diet contained 7% NaCl. After four weeks on these diets, the rats were decapitated and blood was obtained for the measurement of plasma electrolytes, intraerythrocyte sodium, potassium and magnesium content (RBC-Na, -K, in mEq/L cells and RBC-Mg, in mg/dL cells) and plasma beta-endorphin concentration (beta-END, in pg/mL). In the control group, systolic blood pressure and RBC-Na were obviously higher than in the other groups. Plasma beta-endorphin concentration was 45.1 +/- 13.4 in the control group, 70.7 +/- 17.4 in the Ca-group (P less than .05 v control group), 58.0 +/- 20.1 in the Mg-group and 83.8 +/- 24.8 in the Ca/Mg-group (P less than .01 v control group). The blood pressure correlated significantly with both RBC-Na (r = 0.416, P less than .01) and beta-END (r = 0.436, P less than .005). A negative correlation was also observed between RBC-Na and beta-END (r = 0.437, P less than .005).
Hypothalamic or central obesity is associated with an early rise in plasma insulin concentration. Insulin levels in a 7-year-old boy with hyperphagia and obesity following an episode of meningoencephalitis were studied sequentially during the course of progressive weight gain. High fasting insulin levels (1183 pmol/L) and strikingly high insulin release in response to glucose (7892 pmol/L) were found within weeks of the onset of the illness. The abnormality in insulin secretion occurred prior to the marked weight gain. Hyperinsulinemia was not accompanied by hypoglycemia. Early hyperinsulinemia may be a primary event in the development of hyperphagia and obesity following hypothalamic injury.
Heart rate adjustment of exercise-induced ST segment depression. Improved risk stratification in the Framingham Offspring Study BACKGROUND. Simple heart rate adjustment of ST segment depression during exercise (delta ST/HR index) and the pattern of ST depression as a function of heart rate during exercise and recovery (the rate-recovery loop) have been shown to improve the ability of the exercise electrocardiogram to detect the presence of coronary heart disease (CHD), but the performance of these methods for the prediction of future coronary events remains to be examined. METHODS AND RESULTS. We compared the delta ST/HR index and the rate-recovery loop with standard electrocardiographic criteria for prediction of CHD events in 3,168 asymptomatic men and women in the Framingham Offspring Study who underwent treadmill exercise electrocardiography and who, at entry, were free of clinical and electrocardiographic evidence of CHD. After a mean follow-up of 4.3 years, there were 65 new CHD events: four sudden deaths, 24 new myocardial infarctions, and 37 incident cases of angina pectoris. When a Cox proportional hazards model with adjustment for age and sex was used, a positive exercise electrocardiogram by standard criteria (greater than or equal to 0.1 mV horizontal or downsloping ST segment depression) was not predictive of new CHD events (chi 2 = 0.40, p = 0.52). In contrast, stratification according to the presence or absence of a positive delta ST/HR index (greater than or equal to 1.6 microV/beat/min) and a positive (counterclockwise) rate-recovery loop was associated with CHD event risk (chi 2 = 9.45, p less than 0.01) and separated subjects into three groups with varying risks of coronary events: high risk, when both tests were positive (relative risk 3.6; 95% confidence interval, 2.4-5.4); intermediate risk, when either the delta ST/HR index or the rate-recovery loop was positive (relative risk, 1.9; 95% confidence interval, 1.3-2.8); and low risk, when both tests were negative. After multivariate adjustment for age, sex, smoking, total cholesterol level, fasting glucose level, diastolic blood pressure, and electrocardiographic evidence of left ventricular hypertrophy, the combined delta ST/HR index and rate-recovery loop criteria remained predictive of coronary events (chi 2 = 5.45, p = 0.02). CONCLUSIONS. Heart rate adjustment of ST segment depression by the delta ST/HR index and the rate-recovery loop during exercise electrocardiography can improve prediction of future coronary events in asymptomatic men and women.
In vivo incorporation of [9,10(-3)H]-palmitate into a rat metastatic brain-tumor model. Lipid metabolism of an intracerebrally implanted brain tumor and normal brain was investigated in awake Fischer 344 rats using intravenously injected [9,10(-3)H]-palmitate as a probe. A suspension of Walker 256 carcinosarcoma cells (250 cells in 5 microliters medium), with or without 1% low-melting-point agar, was implanted into the caudate nucleus of rats 8 to 9 weeks old. Control animals received an intracerebral injection without tumor cells. Seven days after implantation, awake rats were infused intravenously for 5 minutes with [9,10(-3)H]-palmitate (6.4 mCi/kg). The rats were killed 20 minutes after initiation of the infusion and coronal brain slices were obtained for quantitative autoradiography and light histological study. Tumor cell masses were histologically well demarcated from the surrounding brain tissue. Tumor tissue incorporation of [9,10(-3)H]-palmitate was heterogeneous, ranging on average from 3.1- to 6.1-fold greater than in the corresponding contralateral brain. In addition, incorporation corresponded to regional tumor cell density. The incorporation rate constant of [9,10(-3)H]-palmitate in tumor was significantly increased compared to control brain and was independent of tumor size. Necrotic areas within tumors showed no incorporation of radiolabeled palmitate. Brain surrounding the tumors and control injection sites showed reactive gliosis, and possessed 30% greater incorporation of [9,10(-3)H]-palmitate than contralateral normal brain. These results suggest that [9,10(-3)H]-palmitate can be used to image brain tumors in vivo, measuring turnover and/or synthesis of tumor and brain lipid.
Response of Bitot's spots in preschool children to vitamin A treatment. In a double-masked, placebo-controlled, clinical trial in Indonesia, 88 preschool children between the ages of 36 and 72 months with Bitot's spots were randomly assigned to 200,000 IU of oral vitamin A or placebo and followed up for five weeks. Baseline and follow-up serum vitamin A levels were obtained. Of the 45 children receiving vitamin A, 33 (73.3%) showed complete cure and disappearance of Bitot's spots, six (13.3%) had disappearance of some but not all Bitot's spots, and six (13.3%) were unresponsive to treatment. The nonresponsive children were older, all male, and had higher initial mean serum vitamin A levels, 23.0 micrograms/dl, compared to 15.9 micrograms/dl in the cured group (P = .017). These data suggest that normal vitamin A status may be found in approximately 13% of children with Bitot's spots before vitamin A intervention and that one fourth of those who had Bitot's spots originally will not be cured of all Bitot's spots after intervention. These are important factors to consider when using Bitot's spots in prevalence surveys as a clinical sign of vitamin A deficiency.