123rc/medical_text huggingface dataset:
The rapid detection of clonal T-cell proliferations in patients with lymphoid disorders. A series of T-cell proliferations in peripheral blood, bone marrow, or tissue samples were analyzed for clonality. The technique used employs the polymerase chain reaction to amplify portions of the rearranged T-cell receptor beta chain genes, using primers recognizing conserved sequences of the variable, diversity, and joining region segments. We examined 17 cases of T-cell lymphoma or leukemia; a clone was identified in 13 cases (76%) overall and in 7 of 8 cases (87.5%) in which both beta-chain alleles were known to be rearranged, as shown by restriction enzyme analysis. No clonal rearrangements were detected in samples from 13 non-T-cell disorders, including B-cell lymphomas, reactive lymphoid proliferations, and nonlymphoid tumors. This method is useful for detecting clones in thymic and post-thymic T-cell malignancies and has the advantages of being extremely rapid (a result is obtained within hours of the biopsy procedure), requiring no radiolabeling, using only a small amount of tissue, and being applicable to formalin-fixed, paraffin-embedded tissue.
Paraneoplastic brachial plexopathy in a patient with Hodgkin's disease. We describe a case of inflammatory brachial plexopathy that occurred in the context of a mild, diffuse sensorimotor peripheral neuropathy associated with Hodgkin's disease. Clinical, electrophysiologic, and pathologic studies helped distinguish this disorder from other causes of brachial plexopathy in patients with cancer. Treatment with corticosteroids seemed beneficial in this patient. We suggest that this may be another type of paraneoplastic condition associated with Hodgkin's disease.
Motor units in incomplete spinal cord injury: electrical activity, contractile properties and the effects of biofeedback. The electrical and contractile properties of hand muscles in a selected population of quadriplegic subjects were studied intensively before and after EMG biofeedback. Spontaneously active motor units and units that could only be slowly and weakly activated were observed in these subjects, in addition to units that were voluntarily activated normally. This suggests a considerable overlap of surviving motor neurons to a single muscle that are below, near or above the level of a lesion. Despite the common occurrence of polyphasic potentials and other signs of neuromuscular reinnervation, the average twitch tension of single motor units in hand muscles of quadriplegic subjects was not significantly different from that in control subjects. Nor did it increase after biofeedback training that typically increased the peak surface EMG by a factor of 2-5 times. The percentage of spontaneously active units was also constant. The surface EMG may be increased during biofeedback by using higher firing rates in motor units that can already be activated, rather than by recruiting previously unavailable motor units.
Gastroesophageal reflux and sclerotherapy strictures. The development of esophageal stricture is common following endoscopic variceal sclerotherapy (EVS). Gastroesophageal reflux may be at least partly responsible. Twelve randomly selected male patients underwent chronic EVS for the management of bleeding esophageal varices. Six patients developed strictures during or after EVS, six did not. There were no significant differences between stricture and nonstricture patients during 24 hour esophageal pH monitoring. Three of the six stricture patients and four of the six nonstricture patients had an abnormal amount of reflux. Gastroesophageal reflux occurs frequently in patients undergoing EVS, and it is not likely to play a major role in EVS stricture formation.
Rhabdomyosarcoma. From the laboratory to the clinic. The prospect of identifying and developing new agents for treatment of rhabdomyosarcomas is discussed in the light of current prognosis for children with advanced stage disease. Preliminary attempts to identify tumor-specific agents using in vitro cell culture show potential promise, but as yet remain unproven. The more complex system of identifying therapeutically active agents using human tumor xenografts has demonstrated usefulness. The potential problems associated with this system are discussed.
Modulation of the stretch reflex during volitional sinusoidal tracking in Parkinson's disease. Sinusoidal visually-guided wrist tracking, in normal and parkinsonian subjects, was perturbed by torque transients every 90 degrees throughout the movement. Long-latency stretch reflex and volitional EMG amplitude modulations were assessed as functions of the tracking phase. Reflex modulation during tracking, both in wrist flexor and extensor muscles, was found to differ significantly between parkinsonian and normal subjects. In the parkinsonian group, the abnormality consisted of an increased reflex activity during tracking phases in which the muscle was lengthening. At these phases the reflex generated torque is opposite in direction to the volitionally generated torque and the tracking movement. No differences in the unperturbed volitional EMG modulation were observed between groups for this error constrained tracking paradigm. Significant correlations were found between ratings of bradykinesia and the amount of abnormal reflex modulation in the wrist flexor. These data suggest that a component of bradykinesia results from a defective coordination of supraspinal reflex and volitional control systems.
Plasma thrombin-antithrombin III complexes in the diagnosis of primary hepatocellular carcinoma complicating liver cirrhosis. Detection of hypercoagulable state might be helpful in the diagnosis of primary hepatocellular carcinoma (HCC) complicating liver cirrhosis (LC). Plasma levels of thrombin-antithrombin III complex (TAT) were determined in 50 patients of LC with or without HCC. The levels were above 2 ng/ml in 80% of 25 HCC patients, but only in 12% of 25 non-HCC patients (P less than 0.01). The levels over 2 ng/ml occurred even in five of six HCC patients whose serum alpha-fetoprotein levels were below 20 ng/ml as well as in two of three patients with HCC less than 2 cm in diameter. Those levels in HCC patients were significantly decreased within 8 days after treatment with transcatheter arterial embolization or infusion of antitumor agents, without affecting plasma antithrombin III levels. These results suggest that plasma TAT levels may be useful in the diagnosis of HCC complicating LC.
Early scintigraphic detection of experimental myocardial infarction in dogs with technetium-99m-glucaric acid Recent data have generated some interest in technetium-99m-(99mTc) glucaric acid as an in vivo viability marker. We studied 99mTc-glucaric acid retention in canine models of myocardial ischemia (20-min occlusion of the LAD/40-min reperfusion), acute myocardial infarction (MI) (90-min LAD occlusion/3-hr reperfusion), and chronic MI (90-min occlusion and either 48-hr or 10-day reperfusion). Regional myocardial blood flow was measured by radiolabeled microspheres. No preferential uptake of glucaric acid was observed in ischemic but viable myocardium. The compound showed high affinity for necrotic myocardial tissue for several days following injury. The preferential uptake in infarcted tissue disappeared by 10 days following injury. This study shows that 99mTc-glucaric acid acts exclusively as a marker of necrosis in canine models of MI. Technetium-99m-glucaric acid may have clinical utility in early cardiac imaging of myocardial infarction and in differentiating recent from old injuries.
Is gastric acid responsible for the pain in patients with essential dyspepsia? The pathogenesis of symptoms in patients with essential dyspepsia is not known. Since treatment with H2-receptor antagonists has provided symptomatic relief in some reports, we carried out the present study to investigate whether gastric acid is responsible for symptoms in these patients. Fifty patients with essential dyspepsia and 25 healthy control subjects were studied. After an overnight fast, a nasogastric tube was passed and its tip positioned in the antrum under fluoroscopic control. Normal saline or 0.1 M hydrochloric acid was infused in a randomized, double-blind fashion. Eleven (22%) patients developed pain with acid infusion, but none with normal saline (p less than 0.005). In 10 of these 11 patients, pain recurred on rechallenge with acid infusion but was promptly relieved with infusion of 1 M sodium bicarbonate. None of the healthy controls developed pain on infusion of acid or saline. These observations suggest that acid has a definite role in the pathogenesis of symptoms in some patients with essential dyspepsia, although other factors may also be important.
Hospital management of voluntary total fasting among political prisoners In 1989 20 political detainees, held without trial for up to 32 months, were admitted, on hunger strike, to the Johannesburg Hospital, South Africa. Most were held under the regulations of the State of Emergency (since revoked) and 5 were held incommunicado under section 29 of the Internal Security Act (still in force). Guidelines for ethical management were based on the Declaration of Tokyo, which included the understanding that such detentions constituted mental torture. Conditions of detention in hospital were complicated by police interference in medical and nursing care, and by the chaining of some prisoners to their beds. Doctors are in a unique position to protest against inhuman treatment of prisoners, and should use this authority.
Cancer mortality in workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin BACKGROUND. In both animal and epidemiologic studies, exposure to dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, or TCDD) has been associated with an increased risk of cancer. METHODS. We conducted a retrospective cohort study of mortality among the 5172 workers at 12 plants in the United States that produced chemicals contaminated with TCDD. Occupational exposure was documented by reviewing job descriptions and by measuring TCDD in serum from a sample of 253 workers. Causes of death were taken from death certificates. RESULTS. Mortality from several cancers previously associated with TCDD (stomach, liver, and nasal cancers, Hodgkin's disease, and non-Hodgkin's lymphoma) was not significantly elevated in this cohort. Mortality from soft-tissue sarcoma was increased, but not significantly (4 deaths; standardized mortality ratio [SMR], 338; 95 percent confidence interval, 92 to 865). In the subcohort of 1520 workers with greater than or equal to 1 year of exposure and greater than or equal to 20 years of latency, however, mortality was significantly increased for soft-tissue sarcoma (3 deaths; SMR, 922; 95 percent confidence interval, 190 to 2695) and for cancers of the respiratory system (SMR, 142; 95 percent confidence interval, 103 to 192). Mortality from all cancers combined was slightly but significantly elevated in the overall cohort (SMR, 115; 95 percent confidence interval, 102 to 130) and was higher in the subcohort with greater than or equal to 1 year of exposure and greater than or equal to 20 years of latency (SMR, 146; 95 percent confidence interval, 121 to 176). CONCLUSIONS. This study of mortality among workers with occupational exposure to TCDD does not confirm the high relative risks reported for many cancers in previous studies. Conclusions about an increase in the risk of soft-tissue sarcoma are limited by small numbers and misclassification on death certificates. Excess mortality from all cancers combined, cancers of the respiratory tract, and soft-tissue sarcoma may result from exposure to TCDD, although we cannot exclude the possible contribution of factors such as smoking and occupational exposure to other chemicals.
An inconsistent relationship between insulin and blood pressure in three Pacific island populations. The evidence linking insulin to blood pressure is controversial, and results for groups similarly categorized by body mass, glucose tolerance and hypertensive status are often contradictory. We have investigated the relationship in three population-based samples of Micronesian (Nauru), Polynesian (Western Samoa) and Melanesian (New Caledonia) Pacific islanders, who are known to be susceptible to obesity, non-insulin-dependent diabetes mellitus (NIDDM), hyperinsulinaemia and hypertension. After controlling for age and body mass index (BMI), mean fasting and 2-hr (post 75 g glucose) insulin levels were not significantly different between hypertensive and non-hypertensive subjects, in any population or glucose tolerance sub-group, excepting 2-hr insulin in New Caledonians with normal glucose tolerance. Similarly, there were no strong trends for a higher prevalence of hypertension amongst those with insulin levels in the upper quartile of the distribution of each population, although it was apparent in some BMI/glucose tolerance sub-groups of two populations. Multiple linear regression analyses also showed an inconsistent and where present, weak, independent association between insulin and blood pressure in models predicting both systolic and diastolic blood pressure. We therefore conclude that the hypothesis implicating insulin as a major determinant of blood pressure and as the pathophysiological link between obesity, NIDDM and hypertension is not strongly supported either by the literature or the present data.
Significance of magnetic resonance imaging in acute head injury. One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).
Similar time course of ST depression during and after exercise in patients with coronary artery disease and syndrome X. To assess whether the time course of ST segment depression differs in patients with coronary artery disease and patients with angina and normal coronary arteries, the exercise tests of 54 patients with documented coronary artery disease and 25 patients with syndrome X (angina, positive exercise test, no evidence of coronary artery spasm, and normal coronary arteries) were compared. All tests were performed with therapy withheld, using the modified Bruce protocol. In each test, time, heart rate and blood pressure were measured at the onset and at 1 mm of ST segment depression, and at peak exercise. Recovery (return of the ST segment to baseline +/- 0.2 mm) time was also assessed. Peak ST segment depression was similar in coronary artery disease and syndrome X patients (1.5 +/- 0.3 versus 1.6 +/- 0.4 mm). In 42 coronary artery disease patients, ST segment depression developed early (less than or equal to 6 minutes) during exercise; this was associated with a short recovery (less than or equal to 3 minutes) in 17 (40%) and with a long recovery (greater than 3 minutes) in 25 (60%) patients. In 17 patients with syndrome X, ST segment depression developed early; it was associated with a short recovery in six (35%) and with a long recovery in 11 (65%) patients. Late (greater than 6 minutes) onset of ST segment depression was observed in 12 coronary artery disease patients; of these, eight (67%) had a short recovery and 4 (33%) had a long recovery. Late onset of ST segment depression occurred in eight patients with syndrome X; six (75%) had a short recovery and two (25%) had a long recovery.
Late development of a squamous carcinoma in a reconstructed pharynx. We report a case in which a squamous cell carcinoma was found to have arisen from a delto-pectoral skin flap used in pharyngeal reconstruction. The flap had been forming a neo-pharynx for 24 years. No other signs of recurrent disease had developed in this period. This raises the possibility of tumour induction in heterotopic skin used for oropharyngeal reconstruction.
Estrogen replacement and coronary artery disease. Effect on survival in postmenopausal women. The relationship among postmenopausal estrogen use, coronary stenosis, and survival was examined retrospectively in 2268 women undergoing coronary angiography. The patients were selected for study if their age was 55 years or older at the time of angiography or if they had previously undergone bilateral oophorectomy. Postmenopausal estrogen use in 1178 patients with coronary artery disease (greater than 70% stenosis) and 644 patients with mild to moderate coronary artery disease (5% to 69% stenosis) was compared with 446 control subjects (0% stenosis) using life-table analysis. Over 10 years of follow-up, there was no significant difference in survival among patients initially free of coronary lesions on arteriography who had either never used (377) or ever used (69) estrogens. Among patients with mild to moderate coronary stenosis, 10-year survival of those who had never used estrogens was 85.0% and it was 95.6% among 99 "ever users." Survival was 60.0% among those with more than 70% coronary stenosis who had never used estrogen and it was 97.0% among 70 ever users. The "never users" group were older (65 vs 59 years), had a lower proportion of cigarette smokers (40% vs 57.1%), a higher proportion of subjects with diabetes (21.7% vs 12.9%) and hyperlipidemia (58% vs 44%), and approximately equal numbers of hypertensives (56.0% vs 54.3%). Cox's proportional hazards model was used to estimate survival as a function of multiple covariables. Estrogen use was found to have a significant, independent effect on survival in women. We conclude that estrogen replacement after menopause prolongs survival when coronary artery disease is present, but it has less effect in the absence of coronary artery disease.
Gallstone dissolution. Many methods are available for gallstone dissolution, including oral bile salts; cholesterol solvents such as mono-octanoin or methyl tert-butyl either; and calcium or pigment solvents such as EDTA and polysorbate. Which of these approaches will be appropriate for an individual patient depends on the type of stones; whether they are in the gallbladder or the bile ducts; whether access to the biliary tree is available; the patient's age and general medical condition; and the availability of necessary expertise. In the US, both chenodeoxycholate and ursodeoxycholate are now available. Ursodeoxycholate is more expensive but appears to produce fewer side effects and may be more efficacious. These agents are most effective in thin women with small floating, radiolucent cholesterol stones in a functioning gallbladder. Only about half of the small subset of patients will experience partial or complete dissolution of stones within a year. Stone recurrence and the potential toxicity of long-term therapy are problems with this approach. Therefore, for most patients, cholecystectomy, either in the traditional fashion or using a laparoscopic approach (see article later in this issue by Gadacz et al), is the most cost-effective and perhaps the safest option. Intragallbladder instillation of methyl tert-butyl ether probably will be applicable only to a small subset of patients, and treatment is likely to be followed by a high recurrence rate. In patients with retained common duct cholesterol stones and access to the biliary tree, mono-octanoin therapy is advantageous in that it can be initiated as soon as cholangiography demonstrates no extravasation. In properly selected patients, a 90% success rate with this technique can be expected within 7 days.
Two-year outcome after angiographically documented myocardial reperfusion for acute coronary occlusion. Thrombolysis and Angioplasty Study Group. Reperfusion therapy has been clearly shown to decrease the early mortality after acute myocardial infarction, but the impact of this therapy on long-term survival has been less extensively evaluated. This study reports the extended follow-up of a large cohort of 810 patients treated with intravenous thrombolytic therapy combined, when considered necessary to maintain or augment infarct vessel patency, with mechanical reperfusion therapies. Each patient underwent coronary angiography within 2 hours of the initiation of the thrombolytic infusion. Coronary angioplasty was performed in 62% of the patients before hospital discharge and 21% underwent coronary artery bypass graft surgery. Follow-up was obtained in 96% to a mean of 18.8 months (range, 1.5 to 48 months). All-cause mortality over this period was 3.3%; 2.1% died from cardiac causes. Nonfatal reinfarction occurred in 5.1%. Although the low event rate limits the validity of statistical comparisons, the patients who survived the follow-up period tended to be younger (56 +/- 10 vs 65 +/- 7 years), to have better predischarge left ventricular function (left ventricular ejection fraction, 52 +/- 11 vs 46 +/- 13%) and to have a lower prevalence of multivessel coronary artery disease (45 vs 67%). This excellent long-term survival may, in part, reflect the exclusion of high-risk patients from enrollment in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) studies. It may also be attributable, however, to the frequent use of combined thrombolysis and mechanical revascularization in this population.
Reconstruction of patellar tendon rupture after total knee arthroplasty with an extensor mechanism allograft. Although patellar tendon rupture after total knee arthroplasty (TKA) is a rare complication, the consistently poor outcome of conventional tendon repair has convinced some to abandon such reconstruction in favor of a prospective protocol using an allograft distal extensor mechanism. The graft consists of a quadriceps tendon, a patella with a cemented prosthesis, a patellar tendon, and a tibial tubercle. Since December 1985, 13 knees in 12 patients were reconstructed using this method. Ten knees were followed for six to 51 months; five of these knees were followed for more than 24 months. Knee extension power and improved function were ultimately attained in all cases, although minimal extensor lags were present in three cases. Preoperative motion returned in all but one knee. Healing of the allograft to the host tissue was attained primarily at all of the tibial junctions. Two graft complications occurred, both in the first three months after surgery: one quadriceps junction treated by resuture failed at the one-month mark, and the other graft had to be revised for extensor weakness from rupture of the graft at the patella-patellar tendon junction, which was attributed to surgical damage to the tendon. After completion of healing to the host and rehabilitation of the knee joint, no grafts in the series failed during the course of normal daily activities. One patient fractured the allograft patella in a severe fall. The long-term durability of this construct needs to be studied further.
Computed tomographic and ultrasonographic findings in women with acute fatty liver of pregnancy. Acute fatty liver of pregnancy is associated with complications that can influence antepartum management and necessitate delivery. To date, liver biopsy has been regarded as the "gold standard" for diagnosis. Radiologic evaluation of the liver has been suggested as a less invasive means of diagnosing this entity. Five patients with acute fatty liver of pregnancy underwent ultrasonography; three underwent concomitant computed tomography (CT) of the liver. The liver appeared to be normal in all the patients undergoing CT evaluation and all undergoing ultrasonography except one. Normal liver examinations are not unusual findings in patients with acute fatty liver of pregnancy.