123rc/medical_text huggingface dataset:
Preferential localization of human adherent lymphokine-activated killer cells in tumor microcirculation. The efficacy of adoptive immunotherapy for solid tumors with lymphokine-activated effector cells presumably depends on the ability of these cells to localize adequately in tumor tissues. We present here the first quantitative study of the in vivo movement of fluorescently labeled adherent lymphokine-activated killer (A-LAK) cells. These cells were injected intra-arterially along with low-dose interleukin-2 into normal (mature granulation) tissue and an implant of VX2 carcinoma grown in the rabbit ear chamber. A small proportion of A-LAK cells accumulated preferentially in the tumor microcirculation in vivo because of an increased frequency of long-term adhesive interactions with the tumor vasculature. Stasis of blood flow in the tumor vasculature was observed 1 to 2 days after injection. Subsequent necrosis of the tumors was observed, along with diffuse infiltrates of lymphocytes, monocytes, and granulocytes in the interstitial space within the tumor. Development of necrosis despite low ratios of effector cells to target cells suggests that in addition to direct cytotoxicity, the response to adoptive immunotherapy is mediated via the tumor vasculature. This novel mechanism for adoptive immunotherapy must be taken into account in the development of improved strategies for cancer treatment.
Peripheral arterial occlusive disease of the extremities in the United States: hospitalization and mortality. PAODE is an important cause of morbidity and health care expenditures among the elderly. Data from the NHDS and National Vital Statistics System were used to assess its impact in the U.S. In 1985 to 1987, an estimated 229 thousand men and 184 thousand women per year were discharged with any diagnosis of chronic PAODE. Discharge rates were much higher in men and increased sharply with age. Lower extremity arteriography was performed during 88 thousand hospitalizations and aorta-iliac-femoral bypass procedures were done during 31 thousand hospitalizations per year. Numbers of procedures increased markedly since 1979. An estimated 60 thousand men and 50 thousand women per year were discharged with any diagnosis of acute PAODE. Embolectomy or thrombectomy of lower limb arteries was listed for 28 thousand discharges per year. Few deaths were attributed to PAODE. Although these data are limited by likely incomplete reporting and by the nonspecificity of diagnostic codes, they provide an indication of the magnitude of the problem. An aging population and advances in surgical techniques suggest continued monitoring using multiple data sources. Vigorous primary prevention programs are needed to lessen the impact of all atherosclerotic diseases.
Quantification of vascular stenosis with color Doppler flow imaging: in vitro investigations. The accuracy of quantifying the degree of vascular stenosis with color Doppler flow imaging (7.5-MHz, linear array system) was determined in an experimental study carried out on six concentric and five eccentric model stenoses (cross-sectional area reduction, 13.4%-93.8%). The measurements were made with use of pulsatile flow at four different flow rates (70.8-339.0 mL/min). The degree of stenosis was calculated from the ratio of prestenotic to intrastenotic flow velocity. The most exact measurement of the degree of stenosis could be achieved with Doppler spectral analysis by determining the maximum peak systolic velocity (r = .994, y = 0.98x - 3.2). With the velocity values derived only from the color-coded image, it was also possible to find the most exact degree of stenosis (r = .995, y = 0.99x - 2.9). For quantification of stenosis, pre- and intrastenotic Doppler spectral analysis is no longer necessary if the stenosis can be imaged sufficiently with color Doppler.
Lung injury in a surfactant-deficient lung is modified by indomethacin. Repetitive total lung lavage in adult rabbits leads to a reproducible severe surfactant-deficient lung injury. Hypoxemia requiring mechanical ventilation occurs, accompanied by a substantial pulmonary hypertension, a large intra-alveolar protein leak, peripheral neutropenia, and pathological features of marked neutrophil infiltration with extensive hyaline membrane formation. Pretreatment with indomethacin abolishes postlavage pulmonary hypertension, preserves a slightly better lung function with higher arterial PO2, and prevents the postlavage peripheral neutropenia found in untreated animals. Pretreatment with a thromboxane A2 receptor blocker (L 655,240, Merck Frosst, Canada) also completely attenuated pulmonary hypertension, providing evidence that thromboxane A2 mediates pulmonary arterial hypertension after lung lavage. However, specific thromboxane receptor blockade had no other long-lasting beneficial effects on the ongoing injury in this model.
Cisplatin-fluorouracil interaction in a squamous cell carcinoma xenograft. Patients with squamous cell carcinoma of the head and neck are treated with cisplatin and fluorouracil according to a schedule based on the findings of clinical studies. A similar schedule showed a supra-additive effect in the treatment of xenografted human squamous cell carcinoma of the head and neck. We sought to ascertain whether this schedule was optimal. A single intraperitoneal injection of cisplatin (7.5 mg/kg) was combined with three injections of fluorouracil given during a 24-hour period (total dose, 150 or 80 mg/kg) before, during, or after cisplatin administration. The combined effect of cisplatin and fluorouracil on tumor growth and toxic effects was schedule dependent. Consideration of both toxic effects and tumor growth inhibition, as assessed by reduction of the area under the growth curve, the optimal administration interval was found to be fluorouracil given 3 days after cisplatin administration.
Evaluation of preoperative computed tomography in gastric malignancy. Ninety patients with gastric malignancy underwent computed tomography (CT) before surgery. The CT findings regarding neoplastic invasion of adjacent organs and metastasis or enlarged lymph nodes were compared with the findings at laparotomy (85 cases) or autopsy (5 cases), thus permitting evaluation of the diagnostic accuracy of CT and its usefulness for predicting resectability. When present, neoplastic invasion of adjacent organs was overestimated or underestimated by CT in 21 cases. Invasion of adjacent organs according to CT was false positive in 17 cases and false negative in 11 cases. When liver metastasis or enlarged regional or distant lymph nodes were present, CT overestimated or underestimated their extent in 17 cases, and the diagnosis was false positive in one case and false negative in 33 cases. The positive and negative predictive values of CT concerning resectability of the tumor were 81% and 64%, respectively. Routine preoperative CT in gastric malignancy is concluded to be of limited value and surgical exploration, when feasible, remains the method of choice.
Effects of short spaceflights on mechanical characteristics of rat muscles. The aim of this study was to investigate the contractile protein characteristics after 5-day (Cosmos 1514) and 7-day (Cosmos 1667) spaceflights. The experiments were performed on skinned fibers from the soleus, gastrocnemius lateralis, and plantaris muscles isolated from Wistar rats. A reduction in fiber diameter might explain the decrease in the maximal tension in the soleus, whereas this tension was unaltered in the gastrocnemius and the plantaris. Moreover the calcium sensitivity of the myofilament appeared modified in the soleus and in the gastrocnemius: The tension/pCa relationships were shifted toward higher calcium concentrations, indicating a decrease in the apparent calcium binding constant of the troponin C. The tension/pCa relationship appeared unaltered in the plantaris after spaceflight. Finally, the studies of the time to reach a steady tension indicated an increase in the rate of force development in the soleus and, on the contrary, a slowing down in the plantaris. No change in the gastrocnemius was found. The results were analyzed with references to the different muscle functions in disuse atrophy.
Preventing stroke by the modification of risk factors. Epidemiologic research has revealed the major risk factors in cerebrovascular disease. This review will concentrate on three important risk factors: elevated blood pressure, the most common and important, since it is responsible for up to 70% of all strokes; raised cholesterol; and smoking. These factors are important not only because they increase the risk of stroke, but also because they are amenable to modification by drugs, diet, or other interventions. Strategies to avoid stroke can either 1) try to produce substantial reductions, usually with drugs, in the level of the risk factor in the few individuals in the population with high levels (the "high-risk" approach), or 2) try to produce modest reductions in the level of the risk factor in every individual in the population, usually not with drugs but with lifestyle modification (the "mass" approach). The prevention of stroke could best be achieved through continuing medical efforts to deal with high-risk individuals and through political strategies to encourage a healthier lifestyle in the population as a whole.
Visual evoked potentials and visual prognosis following perinatal asphyxia. Twenty-five children born at term with perinatal asphyxia were studied at age 2.5 to 4.5 years to evaluate visual function and to determine the prognostic value of postnatal assessments of visual outcome. Postnatal assessments included several visual evoked potentials and electroretinograms in the first week of life. Follow-up assessments included flash and pattern visual evoked potentials, visual evoked potential threshold measurements, and clinical eye examinations. Nineteen children had normal visual function, three were visually impaired, and three remained blind. A strong association was found between normal, abnormal, or absent visual evoked potentials in the early postnatal period and long-term visual outcome (P less than .0001). Other perinatal indicators of asphyxia, including neurologic status, Apgar scores, and arterial pH values, were poor predictors of visual outcome. The risk of visual impairment was limited to those survivors with neurodevelopmental deficits.
Muscle fatigue in McArdle's disease. Muscle fibre conduction velocity and surface EMG frequency spectrum during ischaemic exercise. The origin of fatigue in McArdle's disease is still a matter of debate. Both a reduction of muscle membrane excitability and failure of excitation-contraction (E-C) coupling have been suggested as causes. We performed intermittent isometric biceps brachii contractions (80% maximal voluntary contraction, rate 30/min) under local ischaemia in 5 McArdle's disease patients and 26 healthy controls. Our results show that in McArdle's disease the exerted force is less, the surface EMG (SEMG) amplitude steadily increases, and that the power density spectrum (PDS) shifts to lower frequencies, the latter without significant differences when compared with normals. The most important finding is that muscle membrane excitability remains unimpaired during ischaemic exercise, establishing a dominant role for intramuscular lactic acid formation in the reduction of muscle fibre conduction velocity seen in normal subjects. As is indicated by the shift of the PDS towards lower frequencies, as well as by the increase in SEMG amplitude, it can be concluded that during ischaemic exercise in patients with myophosphorylase deficiency, fatigue occurs without alterations in muscle membrane excitability and is due to a failure of E-C coupling.
Hematoma of the optic nerve sheath after penetrating trauma. We have presented a case involving the diagnosis and management of optic nerve sheath hematoma. Our patient's positive outcome demonstrates the usefulness of megadose steroid therapy for acute optic nerve injury.
Complete remission in refractory anaplastic adult Wilms' tumor treated with cisplatin and etoposide. A 61-year-old woman underwent a left radical nephrectomy for Stage II anaplastic Wilm's tumor. She received no adjuvant therapy. One year later computerized tomography (CT) of the abdomen revealed a mass in the left renal fossa and retroperitoneal adenopathy. A CT-guided needle biopsy was nondiagnostic. The patient had progressive disease after treatment with dactinomycin, doxorubicin, and vincristine, but achieved a complete response after treatment with cisplatin and etoposide. The therapy of Wilms' tumor in adults is discussed.
Renal function after tumor enucleation in a solitary kidney. Whether extensive ablation of renal mass in humans leads to progressive glomerulosclerosis, proteinuria, and hypertension, as it does in animal models, is a matter of controversy. We have studied kidney function in six patients who underwent enucleation of a renal cell carcinoma in a solitary kidney. Four patients had previously had a nephrectomy. The two others each had one atrophic, nonfunctioning kidney. Serum creatinine levels before surgery were within the normal range (mean, 99.9 mumol/L [1.13 mg/dL]). Two weeks after tumor enucleation, creatinine levels were significantly higher than the preoperative values (mean, 124.6 mumol/L [1.41 mg/dL]). The follow-up period varied from 10 to 23 months. In all patients, kidney function improved during the following months. Serum creatinine levels nearly reached preoperative values in all patients (mean, 105.2 mumol/L [1.19 mg/dL]). None of the patients showed a progressive deterioration in renal function or proteinuria. We found a modest increase in blood pressure in two patients who had been normotensive before surgery. In conclusion, tumor enucleation in a solitary kidney did not cause significant renal injury to the remnant kidneys in our patients, at least in the short term.
Glucagonoma syndrome is an underdiagnosed clinical entity. Glucagonomas, considered among the rarest of the islet cell neoplasms, produce a well-defined clinical syndrome characterized by necrolytic migratory erythema, diabetes mellitus, glossitis, anemia, and weight loss. This report describes seven patients with glucagonoma treated at our institution. All seven had the characteristic dermatologic manifestations, present from 1 to 6 years prior to diagnosis. Five patients had extensive disease at the time of initial operation, three of whom underwent aggressive cytoreductive surgery, whereas the other two had biopsy only. The remaining two patients presented with a single nodule each, underwent distal pancreatectomy and splenectomy, and remain free of disease 2 and 6 years postoperatively. Earlier recognition of the distinctive physical findings peculiar to this syndrome should increase survival. Aggressive cytoreductive surgery results in prolonged remission.
Congenital angiotropic lymphoma (intravascular lymphomatosis) of the T-cell type. The autopsy of a stillborn infant showed an extensive intravascular proliferation of atypical cells throughout the body. There was no infiltration by these cells of the parenchyma of the bone marrow, lymph nodes, or thymus. By histochemistry, these cells were negative for naphthol-ASD-chloroacetate esterase, a marker of granulocytes. By immunohistochemistry, they were reactive with MT-1 and anti-Leu-22, but unreactive with MB-1, L26, anti-Leu-M1, Tu-9, and antihemoglobin antibodies. A few cells reacted with antileukocyte common antigen and UCHL-1. Based on these findings, the lesion was diagnosed as angiotropic lymphoma (intravascular lymphomatosis) of the T-cell type, which occurred congenitally. Most angiotropic lymphomas in the literature are of the B-cell type, and no leukemia virus type I antibody was negative in the mother.
Vertebrobasilar occlusion following minor trauma in an 8-year-old boy. An 8-year-old boy developed seizures and coma 2 days after a trivial bicycle accident. Computed tomography failed to show pathology. Magnetic resonance imaging of the head showed infarction of the pons and right cerebellum. Angiography showed occlusion of the right vertebral and basilar arteries. Minor traumatic injuries to the cervical spine may result in vertebrobasilar occlusion. The neurologic manifestations of this disorder and emergency department diagnosis and management are discussed.
Acute pelvic inflammatory disease after surgical sterilization. STUDY OBJECTIVE: Physicians are very cognizant of the possibility of pregnancy after surgical sterilization, but the potential for acute pelvic inflammatory disease (PID) is thought to be rare. This study was undertaken to determine if upper tract PID occurred more frequently than previously reported in patients remote from surgical sterilization. DESIGN: Retrospective review of hospitalized patients with the primary discharge diagnosis of PID. SETTING: Urban, university hospital. PARTICIPANTS: Three hundred sixty-four hospitalized patients with the primary discharge diagnosis of PID over a six-year study period. MEASUREMENTS AND MAIN RESULTS: Patients' age; gynecologic histories and diagnoses; and laboratory, clinical, and surgical findings were noted. Twenty-three cases of acute PID were identified in 21 patients previously sterilized (6%). Nine of the 23 cases had systemic toxicity warranting surgical evaluation; 18 of the 23 cases were admitted from the emergency department. Mean statistical characteristics of the study group were age, 27.3 +/- 0.8 (SE) years; time interval from sterilization, 49.8 +/- 7.4 months; WBC 15,000 +/- 1,200; and temperature, 38.0 +/- 0.2 C. CONCLUSION: We conclude that acute PID may occur more frequently than previously reported in patients with prior surgical sterilization. An increased awareness of this entity is warranted.
Effects of nimodipine on cerebral blood flow and neuropsychological outcome after cardiac surgery. Thirty-five patients undergoing cardiac surgery requiring cardiopulmonary bypass (CPB) were allocated randomly in a prospective double-blind study to receive either nimodipine 0.5 micrograms kg-1 min-1 or placebo. Cerebral blood flow (CBF) was measured during and immediately after CPB. Neuropsychological tests were performed 6 months after surgery to determine any relationship between ischaemic damage and CBF and administration of nimodipine. There were no differences in CBF between the nimodipine (n = 18) and placebo groups (n = 17). Significant changes in neuropsychological tests were found in six patients tested 6 months after surgery but there were no conclusive signs of ischaemic damage. The nimodipine-treated group performed better in tests of verbal fluency and visual retention, suggesting that some memory functions were preserved better in this group.
Gemistocytic astrocytomas: a reappraisal. Although gemistocytic astrocytomas are considered slow-growing astrocytomas, they often behave aggressively. To clarify the biological and clinical behavior of these rare tumors, the authors retrospectively identified 59 patients with gemistocytic astrocytoma whose tumors were diagnosed and treated between June, 1976, and July, 1989. Three patients who were lost to follow-up review were excluded, as were two whose original slides could not be obtained and three whose tumors were diagnosed at recurrence or at autopsy. The pathological material of the remaining 51 patients was reviewed using two sets of histological criteria. Thirteen patients (Group A) had "pure" gemistocytic astrocytoma, defined as a glial tumor with more than 60% gemistocytes/high-power field and a background of fibrillary astrocytes. Fifteen patients (Group B) had "mixed" gemistocytic astrocytoma, defined as a glial tumor with 20% to 60% gemistocytes/high-power field and a background of anaplastic astrocytes. Twenty-three tumors did not meet these criteria and were excluded from analysis. The median age of the patients was 48.5 years in Group A and 38.3 years in Group B (p less than 0.05). In both groups, the median Karnofsky Performance Scale score was greater than 90%. All patients underwent surgical procedures (four total and 19 partial resections, and five biopsies) and postoperative radiation therapy. The majority also had interstitial brachytherapy, chemotherapy, or both. Ten patients had one reoperation for tumor recurrence and one had two reoperations; other treatments for recurrence included brachytherapy, chemotherapy, and repeat irradiation. All four patients who originally underwent gross total resection are still alive; all five who had a biopsy have died. There was no significant difference in median survival times between groups: 136.5 weeks in Group A (range 10 to 310+ weeks) and 135.6 weeks in Group B (range 31 to 460+ weeks). Analysis of all 28 patients showed a better prognosis for patients less than 50 years of age (185 vs. 36 weeks survival time; p less than 0.001), patients with preoperative symptoms lasting for more than 6 months (228.1 vs. 110.2 weeks survival time; p less than 0.05), and patients with seizures as the first symptom (185.7 vs. 80 weeks survival time; p less than 0.01). Survival time did not correlate with the presence of perivascular lymphocytic infiltration. The authors conclude that the presence of at least 20% gemistocytes in a glial neoplasm is a poor prognostic sign, irrespective of the pathological background. It is proposed that gemistocytic astrocytomas be classified with anaplastic astrocytomas and treated accordingly.
Septal ventricular pacing in the immature canine heart: a new perspective. Cardiac pacing initiated from epicardial or transvenous apical right ventricular electrodes causes asynchronous ventricular contraction. This alters myocardial stress vectors and results in adverse cellular and subcellular changes in the experimental animal. Clinically, such changes may contribute to the adverse hemodynamics reported with long-term ventricular pacing. To determine the feasibility of direct stimulation of the ventricular specialized conduction systems and therefore the potential for maintenance of normalized depolarization patterns, 13 beagle puppies were studied. Baseline ventricular activation and contraction patterns were obtained using intracardiac electrograms and multigated nuclear acquisition (MUGA) imaging. Septal electrode insertion from the aortoatrial groove was accomplished by use of two-dimensional echocardiography and continuous electrocardiographic (ECG) monitoring of the surface ECG during pacemaker implantation in five puppies. Standard right ventricular epicardial electrodes were implanted in five additional animals, with three remaining as age-matched non-paced controls. After 4 months of observation, repeat MUGA imaging and intracardiac electrograms demonstrated nearly normal biventricular activation and contraction patterns among the septal-paced group. Histopathologic examination illustrated normal cellular morphology in the septal-paced animals. This study demonstrates that pacing electrode insertion into the proximal interventricular septum is feasible and results in utilization of the normal ventricular conduction pathway. Such an approach to initiation of ventricular stimulation may attenuate the adverse effects of long-term ventricular pacing.