123rc/medical_text huggingface dataset:
Radioimmunology. Imaging and therapy. Targeting of radioactivity to tumors using antitumor antibodies is evolving from a laboratory curiosity toward a practical diagnostic and therapeutic technique that promises widespread benefits for many common human cancers. The development of the hybridoma technique by Kohler and Milstein for producing monoclonal antibodies is probably the single most important contribution to the development of this field. A large array of monoclonal antibodies against many human tumors have been created and labeled with a variety of radioisotopes; 110 clinical trials have been identified from the literature between the interval of 1978 to the present. These studies are beginning to form the basis for certain conclusions regarding likely benefits for certain combinations of antitumor antibodies and isotopes in specific instances of clinical management in patients with malignant neoplasms. For example, in melanoma, lymphoma, neuroblastoma, and colorectal malignancies, radiolabeled antibodies have demonstrated occult tumors, which could not be disclosed with conventional methodologies. Radioimmunotherapy of malignant lymphoma is achieving durable remissions in patients who have failed conventional forms of therapy. For the most part, these advances have been achieved through intelligent application of known principles of immunochemistry, imaging physics, and tumor immunology. Progress has been slow but steady. In a few instances, the term "magic bullet" is warranted in describing the targeting of a particular radiolabeled antibody to a human tumor. I-131, 3-F8, an IgG3 against the GD2 antigen of neuroblastoma, which was introduced by Cheung, and In-111 T-101, against the CD5 antigen of T-cells, which was developed by Royston, stand out because of the consistency and high concentration of radioactive targeting to human tumors in clinical trials. If certain technical innovations fulfill their initial promise, the future will be bright for radioimmunologic methods of diagnosis and therapy. Genetic engineering will permit the development of "humanized" antibodies with biologic properties that favor tumor localization. New chemical approaches will broaden the range of isotopes available as diagnostic and therapeutic radiolabels. Application of modern imaging methodologies, such as positron emission tomography (PET), will detect more lesions of smaller size and permit quantitative imaging for dosimetry considerations. Greater speed and ease of use of computerized work stations will lead to the broader application of fusion imaging in which radioantibody images will be viewed simultaneously with TCT or MRI for better anatomic correlation of abnormal sites of antigen-reactive tumor deposits.
Influence of preservation or perfusion of intraoperatively identified spinal cord blood supply on spinal motor evoked potentials and paraplegia after aortic surgery. Permanent ligation of arteries supplying blood to the spinal cord in operations for aortic aneurysm can lead to spinal cord ischemia, which can result in either paraparesis or paraplegia. This report describes a rapid method of intraoperative identification of those arteries that supply the spinal cord by use of an intrathecal platinum electrode to detect hydrogen in solution that has been injected into the aortic ostia. Preservation or perfusion of those identified arteries supplying the spinal cord may decrease the rate of postoperative neurologic complications. Of 28 porcine experiments with postoperative observation for 24 hours, there were 3 initial pilot experiments in which saline saturated with hydrogen was injected into the temporarily cross-clamped aorta. Twenty animals were then randomized to (1) preservation of only the vessels sequentially identified to supply blood to the spinal cord from T-13 to L-5 (n = 10); (2) division of the vessels supplying the spinal cord (n = 10). A further five animals underwent perfusion experiments wherein the identified cord arteries were perfused by a shunt, the other nonsupply arteries were divided, and the aorta was kept clamped for 45 minutes. Spinal motor evoked potentials were elicited with an intrathecal electrode and were highly sensitive for paralysis. Paralysis occurred in 0/3 pilot (p less than 0.013 vs division); 8/10 division; 1/10 preservation (p less than 0.0017 vs division); and perfusion 1/5 (p less than 0.025 vs division). Results of a pilot study in eight humans shows that the technique can be used to rapidly identify segmental arteries supplying the spinal cord, to determine if distal perfusion is supplying the spinal cord with blood flow, and if reattached segmental arteries are patent.
Coccydynia. Aetiology and treatment. A five-year prospective trial involving 120 patients was undertaken to investigate the aetiology and treatment of coccydynia. The cause lies in some localised musculoskeletal abnormality in the coccygeal region. Lumbosacral disc prolapse is not a significant factor. The condition is genuine and distressing and we found no evidence of neurosis in our patients. Physiotherapy was of little help in treatment but 60% of patients responded to local injections of corticosteroid and local anaesthesia. Manipulation and injection was even more successful and cured about 85%. Coccygectomy was required in almost 20% and had a success rate of over 90%.
Sudden cardiac death while wearing a Holter monitor. The Holter tapes of 61 patients (46 men, mean age +/- standard deviation 65 +/- 11 years) with sudden cardiac death while being monitored were analyzed. Thirty-eight patients were known to have coronary artery disease, 5 had cardiomyopathy, and 7 had aortic valve disease. Etiology remained unknown in 11 patients. Mean New York Heart Association functional class was 2.5 +/- 0.7. Thirty patients had received antiarrhythmic drugs and 32 had received digitalis. Sudden death occurred at rest in 73%. In the hours before death, repetitive ventricular arrhythmias were found in 50 patients (82%), with atrial fibrillation in 34%. Patients with bradyarrhythmic death (18%) had less complex ventricular activity compared to patients with tachyarrhythmic death (p less than 0.01). Lethal arrhythmias--monomorphic ventricular tachycardia, polymorphic ventricular tachycardia, torsades de pointes, primary ventricular fibrillation, and 1:1 conducting atrial tachycardia--were found in 26 (43%), 15 (25%), 5 (8%), 3 (5%), and 1 patient, respectively. The coupling interval of the final ventricular tachycardia correlated inversely with the initial frequency of ventricular tachycardia (p less than 0.05). For patients with tachyarrhythmic death, an increase of heart rate within the last 3 hours was noted (83 vs 89 beats/min, p less than 0.05). Ventricular premature complexes and the proportion of patients with greater than 2 couplets and greater than 2 triplets increased significantly only within the last hour before death.
Enhanced activity of the free radical producing enzyme xanthine oxidase in hypoxic rat liver. Regulation and pathophysiologic significance. It has been widely proposed that conversion of xanthine dehydrogenase (XDH) to its free radical-producing form, xanthine oxidase (XOD), underlies ischemic/reperfusion injury, although the relationship of this conversion to hypoxia and its physiologic control have not been defined. This study details the time course and control of this enzymatic interconversion. In a functionally intact, isolated perfused rat liver model, mean % XOD activity increased as a function of both the duration (25 to 45% in 3 h) and degree (r = 0.97) of hypoxia. This process was markedly accelerated in ischemic liver by an overnight fast (45 vs. 30% at 2 h), and by imposing a short period of in vivo ischemia (cardiopulmonary arrest 72%). Moreover, only under these conditions was there a significant rise in the XOD activity due to the conformationally altered XDH molecule (XODc, 18%), as well as concomitant morphologic injury. Neither circulating white blood cells nor thrombosis appeared to contribute to the effects of in vivo ischemia on enzyme conversion. Thus, it is apparent that conversion to the free radical-producing state, with high levels of XOD activity and concurrent cellular injury, can be achieved during a relatively short period of hypoxia under certain well-defined physiologic conditions, in a time course consistent with its purported role in modulating reperfusion injury. These data also suggest that the premorbid condition of organ donors (e.g., nutritional status and relative state of hypoxia) is important in achieving optimal organ preservation.
Interruption of professional and home activity after laparoscopic cholecystectomy among French and American patients. With a laparoscopic approach, patients can undergo cholecystectomy with a shorter hospitalization, minimal pain, and quicker recovery. It has not been demonstrated, however, that patients actually return to work after laparoscopic cholecystectomy faster than the traditional 4- to 6-week absence from work after a standard open procedure. A survey of 104 French and 84 American patients undergoing laparoscopic cholecystectomy revealed that postoperative discomfort was completely resolved in 2 weeks in 73% of French and 93% of American patients. All but 11 French and 5 American patients were back to normal home activities by 2 weeks after the operation. Of the 35 American and 40 French patients who had professional activity outside the home, 63% and 25%, respectively, returned to work within 14 days. Five (14%) of the American patients and 12 (30%) of the French patients returned to work 4 weeks or more after the operation. The amount of physical activity on the job correlated with the period off work, but, interestingly, at least six patients with very hard physical activity at work (including construction workers) were able to return to full work activity within 1 week. These data suggest that early return to work is possible and that pain resolves quickly after laparoscopic cholecystectomy. The economic benefit of having patients back on the job quickly, however, may be less than expected until cultural norms change with regard to leave of absence after major surgery.
p53 mutations in colorectal cancer. Immunohistological staining of primary colorectal carcinomas with antibodies specific to p53 demonstrated gross overexpression of the protein in approximately 50% of the malignant tumors examined. Benign adenomas were all negative for p53 overexpression. To determine the molecular basis for this overexpression we examined p53 protein expression in 10 colorectal cancer cell lines. Six of the cell lines expressed high levels of p53 in ELISA, cell-staining, and immunoprecipitation studies. Direct sequencing and chemical-mismatch-cleavage analysis of p53 cDNA by using the polymerase chain reaction in these cell lines showed that all cell lines that expressed high levels of p53 were synthesizing mRNAs that encoded mutant p53 proteins. In two of those four cell lines where p53 expression was lower, point mutations were still detected. Thus, we conclude that overexpression of p53 is synonymous with mutation, but some mutations would not be detected by a simple immunohistochemical analysis. Mutation of the p53 gene is one of the commonest genetic changes in the development of human colorectal cancer.
Magnetic resonance imaging of fourth ventricular epidermoid tumors. Two pathologically proved cases of epidermoid tumor of the fourth ventricle are presented; clinical history and computed tomographic, magnetic resonance imaging, and histopathologic findings are included.
Cloning of a gene that is rearranged in patients with choroideraemia Choroideraemia (tapetochoroidal dystrophy, TCD), a common form of X-linked blindness, is characterized by progressive dystrophy of the choroid, retinal pigment epithelium and retina. Previous studies have assigned the TCD gene to a small segment of the Xq21 band. By making use of reverse genetics strategies we have isolated eight overlapping complementary DNA clones from the same chromosomal region. The corresponding gene is expressed in retina, choroid and retinal pigment epithelium. The cDNAs encompass an open reading frame of 948 base pairs that is structurally altered in eight TCD patients with deletions, and in a female patient with a balanced translocation involving Xq21. These findings provide strong evidence that we have cloned the gene underlying choroideraemia. Elucidation of its function should provide new insights into the molecular mechanisms responsible for this disorder and other hereditary retinopathies.
The influence of calcium alginate haemostatic swabs upon operative blood loss in adenotonsillectomy. Although adenotonsillectomy is regarded as a minor procedure, it has been shown that 18% of patients may experience an operative blood loss of 10-20% of the total blood volume. The aim of this study was to determine whether calcium alginate haemostatic swabs reduce operative blood loss in adenotonsillectomy. Seventy-two patients (ages 2-12 years) entered a prospective trial in which the operation was performed either with normal gauze swabs or calcium alginate swabs. Thirty-six children were randomized to each group. The mean blood loss was found to be 34.9 ml (2.07% of total blood volume) and 47.8 ml (2.97% of total blood volume) respectively. Although there was no significant reduction in operative blood loss using calcium alginate, in both groups the blood loss was much smaller than that stated by the majority of previous workers.
Bronchobiliary fistula detected by cholescintigraphy. We present a case of a bronchobiliary fistula initially detected by hepatobiliary scintigraphy. The patient developed bilioptysis 18 mo after undergoing a right hepatic lobectomy and resection of the common bile duct for cholangiocarcinoma. The procedure was complicated by the development of a subphrenic abscess that required percutaneous biliary drainage.
Edwards' syndrome after the replacement of cryopreserved-thawed embryos. A case of Edwards' syndrome after the replacement of frozen-thawed embryos is reported. The presence of cardiac abnormalities and limb deformities raised the suspicion of chromosomal abnormality. The diagnosis of trisomy 18 was made by cytogenetic analysis of fetal blood from the umbilical vein. The chromosomal nondisjunction might have been spontaneous or because of freezing and thawing. If it occurred as a result of freezing and thawing, it is more likely that this was at the first cleavage division rather than the second meiotic division because the embryos were frozen at the late pronuclear stage. Unfortunately, there were no karyotypic markers in the couple's chromosomes to time the nondisjunction. The wisdom of using donor oocytes in an ovum donation program from patients with long-standing infertility is questioned.
Hexamethonium and midazolam terminate dysrhythmias and hypertension caused by intracerebroventricular bupivacaine in rabbits. Previous studies have demonstrated that bupivacaine administered directly into the central nervous system (CNS) is capable of producing signs of bupivacaine cardiovascular toxicity. To investigate the mechanisms by which bupivacaine may act within the CNS to produce cardiovascular toxicity, we studied four groups of halothane-anesthetized rabbits in which infusion of intracerebroventricular (icv) bupivacaine or intravenous (iv) phenylephrine resulted in dysrhythmias and hypertension. In group 1 (n = 5), icv bupivacaine (500 +/- 79 micrograms [mean +/- SEM]) produced dysrhythmias lasting 73 +/- 13 min, whereas icv saline caused no dysrhythmias or hypertension. In group 2 (n = 9), icv bupivacaine-induced hypertension and dysrhythmias were abolished by icv midazolam in 4.4 +/- 0.6 min, and when dysrhythmias and hypertension recurred (22 +/- 0.9 min), hexamethonium (10 mg/kg iv) promptly terminated dysrhythmias and hypertension (14 +/- 1 s). In group 3 (n = 10), icv bupivacaine-induced dysrhythmias and hypertension were not affected by increasing the inspired halothane concentration from 0.8 to 1.6%. In group 4 (n = 6), iv phenylephrine-induced dysrhythmias and hypertension were not affected by icv midazolam. These results suggest that icv bupivacaine produces dysrhythmias and hypertension by increasing autonomic nervous system (ANS) outflow from the brain stem. The finding that peripheral autonomic blockade by hexamethonium rapidly terminated dysrhythmias and hypertension supports this mechanism. We speculate that icv bupivacaine produces an increase in autonomic outflow by blockade of the inhibitory gamma-aminobutyric acid (GABA) neurons that are known to be the principal tonic inhibitors of the ANS.
The use of Glisson's capsule flap in reduced orthotopic hepatic transplantation. The technique of graft reduction has increased the donor pool for children in need of orthotopic hepatic transplantation. However, this technique has been associated with increased perioperative blood loss. Further refinements, such as covering the cut surface of the donor hepatic duct with a flap of Glisson's capsule, may help reduce this complication.
Parathyroid hormone and cirrhosis of the liver. Fifty patients with liver cirrhosis (36 alcoholic, 1 drug-induced, 7 posthepatitic, and 6 cryptogenic) and normal renal function were investigated to determine whether PTH levels in serum, measured using the common midregion human PTH-(44-68) RIA, are elevated in such patients and whether this is related to impaired liver function rather than to the effect of secondary hyperparathyroidism. Their data were compared with those from 25 control subjects. The median PTH level of 462 +/- 18 ng/L (+/- SEM) was significantly increased (P less than 0.01) in cirrhotics compared with that of 236 +/- 13 ng/L in the control group. Significant correlations were found between PTH levels and parameters of liver function such as prothrombin time (r = -0.40; P less than 0.01), albumin as a percentage of total protein (r = -0.48; P less than 0.01), bilirubin (r = 0.35; P less than 0.05), albumin (r = -0.34; p less than 0.05), and cholesterol (r = -0.32; P less than 0.05), but not for antipyrine clearance, suggesting increasing PTH with decreasing liver function. The median calcium level (2.26 +/- 0.03 mmol/L), corrected for changes in albumin, was near the lower limit of the normal range (2.25-2.60), but corrected calcium and PTH were positively correlated (r = 0.33; P less than 0.05), indicating that the elevation is not reactive to calcium depletion. A negative correlation existed between PTH and 25-hydroxy-cholecalciferol (r = -0.49; P less than 0.05), the main circulating metabolite of vitamin D. Normal values in an immunoradiometric assay that detects the whole sequence of human PTH-(1-84) suggest that fragments rather than the intact hormone are responsible for PTH elevations in cirrhosis. The positive correlation between midregion PTH and corrected calcium is probably an artifact of the correction formula. In conclusion, midregion PTH fragments are increased in patients with liver cirrhosis. The reason for this elevation may well be the impaired liver function rather than secondary hyperparathyroidism.
Prochlorperazine and transdermal scopolamine added to a metoclopramide antiemetic regimen. A controlled comparison. Cisplatin-induced nausea and vomiting occurs both acutely and over a prolonged period of time. These symptoms may be incapacitating and are frequently given as a reason to discontinue therapy. We compared prochlorperazine and transdermal scopolamine when added to a standardized metoclopramide antiemetic regimen. Twenty-seven patients receiving cisplatin at 100 mg/m2 were randomly assigned to one of the two treatment arms. Patients were observed during chemotherapy and answered a standard questionnaire 24-26 hours later. Among similar treatment groups no differences were seen regarding the number of emetic events, level of nausea, degree of sedation or overall acceptability of one treatment arm or another. While not superior to prochlorperazine, transdermal scopolamine is a useful antiemetic agent and can be combined with metoclopramide in an attempt to reduce cisplatin-induced nausea and vomiting. Further evaluation of this approach is needed.
Are measurements of height made by health visitors sufficiently accurate for routine screening of growth? To find out whether measurements of height made by health visitors are sufficiently accurate for use in routine screening of children we carried out an interobserver and intraobserver reliability study. Height measurements were made on a group of 10 children aged 3 years old and 10 aged 4.5 years old by two sets of four health visitors. They used a Microtoise or wall chart and the measurements were compared with those made by a trained auxologist with a Harpenden stadiometer. For a single assessment of height both pieces of equipment gave reasonably accurate results. In a child aged 3 years, with height measured on the Microtoise as 100 cm, the true height could be expected--with 95% probability--to lie between 99.2 cm-101.8 cm. At the age of 4.5 years, if the measurement was 110 cm, the child's true height could be expected to lie between 108.9 cm and 111.9 cm. The narrowest confidence interval for the growth rate from 3 to 4.5 years was achieved with the Microtoise, taking the mean of three measurements. We conclude that measurements made by health visitors are sufficiently accurate for routine screening of height, and the use of such measurements for the calculation of height velocity could be improved by more structured training.
Sudden death associated with undiagnosed Graves' disease. Hyperthyroidism may result in multiple symptoms attributable to an excess of thyroid hormone. We report a case of Graves' disease in association with sudden death in a previously healthy, undiagnosed young female. This case illustrates an unusual initial presentation of Graves' disease.
Tricuspid valve dysplasia or displacement in intrauterine life. In 450 cases of structural heart disease diagnosed prenatally, 38 fetuses (8.5%) had either a dysplastic or a displaced tricuspid valve. The tricuspid valve was dysplastic in 22 fetuses, all of which had evidence of tricuspid regurgitation resulting in right atrial dilation and increased cardiothoracic ratio. An associated abnormality of the pulmonary valve occurred in 16 fetuses. The remaining 16 fetuses had Ebstein's malformation, 14 with evidence of tricuspid incompetence at presentation and 10 with an associated abnormality of the pulmonary valve. Of the 38 cases, the pregnancy was interrupted in 17, spontaneous intrauterine fetal death occurred in 8, 11 infants died postnatally and 2 infants are still alive; additional abnormalities were found in 8 cases (chromosomal anomalies in 2, ventricular septal defects in 2, corrected transposition in 2, the Chiari malformation in 2, supraventricular tachycardia in 1 case and coarctation of the aorta in 1). Fetuses with severe abnormalities are selected for fetal echocardiography by the four chamber screening program and a high rate of natural loss both in intrauterine life and immediately after birth was observed in the 21 cases in which pregnancy was continued. This would explain the higher incidence of tricuspid valve disease in our prenatal compared with postnatal series. Although increased cardiothoracic ratio and associated lesions of the right ventricular outflow tract contribute to the poor outcome in the cases detected prenatally, the absence of these features does not always indicate a good prognosis because progression of disease can occur with advancing gestational age. No absolute measurement or single echocardiographic feature emerged as a consistent predictive factor of prognosis.