shukoor65/lab-rag-model huggingface dataset:
Regional changes in hemodynamics and cardiac myocyte size in rats with aortocaval fistulas. 2. Long-term effects. Regional changes in hemodynamics and cardiac myocyte size were examined in adult rats 5 months after creating a large aortocaval fistula. At that time, cardiac output, left and right ventricular pressures, and left and right ventricular dP/dtmax were measured. Subsequently, isolated cardiac myocytes were collected from the left ventricle, right ventricle, and septum for cell size measurements. Compared with sham-operated controls, percent dry weight was reduced in the liver and kidney but was unchanged in the lung. Heart rate, left ventricular systolic pressure, left ventricular dP/dtmax, and systolic aortic pressure were not changed in rats with fistulas. However, cardiac output, stroke volume, left ventricular end-diastolic pressure, and all measured parameters in the right ventricle were significantly increased. Mean cell volume and the ratio of heart weight to body weight were both elevated 92%. Cell volume, cell length, and cross-sectional area increased significantly in each heart region examined. Hypertrophy was more pronounced in cells from the right ventricle and the endomyocardium of the left ventricle. The percentage of cells with mononucleation or binucleation was not changed in any heart region of rats with fistulas. In summary, despite evidence of renal and hepatic congestion, most indexes of cardiac function were normal or elevated 5 months after creation of a large volume-overload-induced hypertrophy. Data from isolated cardiac myocytes suggested that cellular hypertrophy, rather than hyperplasia, was responsible for the increased cardiac mass.
Somatosensory function following dorsal root entry zone lesions in patients with neurogenic pain or spasticity. The goal of this study was to assess the effects of the dorsal root entry zone (DREZ) lesioning procedure, microsurgical DREZ-otomy (MDT), on spinal cord somatosensory function based on peri- and intraoperative clinical and electrophysiological data. The study was performed prospectively on a series of 20 patients suffering from either chronic neurogenic pain or spasticity. Physiological observations were made of the intraoperative evoked electrospinographic recordings as collected from the surface of the spinal cord. The MDT procedure produced analgesia or severe hypalgesia, moderate hypesthesia, and only slight deficits in proprioception and cutaneous spatial discrimination on the body segments operated on. These clinical data correlated well with evoked electrospinographic recordings, which showed a moderate effect of MDT on presynaptic compound action potentials recorded from the spinal cord (N11 and N21), a partial or even reversible effect on the cortical postcentral N20 wave, a more marked effect on the postsynaptic dorsal horn waves N13 and N24 related to large primary afferent fibers, and a disappearance of dorsal horn waves related to finer afferents (N2 and possibly N3). These data provide evidence for an acceptably selective action of MDT on spinal cord nociceptive mechanisms, and for a partial, often slight, involvement of the other somatosensory domains. The presence of abnormal evoked electrospinographic waves is discussed in relation to the mechanisms of neurogenic pain and spasticity. The hypothesis of a "retuning" of the dorsal horn as the mode of action of MDT is presented.
Control of local blood flow in pulmonary inflammation: role for neutrophils, PAF, and thromboxane. The intrapulmonary instillation of C5a results in a local inflammatory response that, in this site, is accompanied by a decrease in local blood flow. Reversal of this decrease by vasodilators or the thromboxane synthesis inhibitor dazmegral has been shown to result in enhanced lung inflammation. In the present study the mechanisms underlying the decrease in flow in pulmonary inflammation were investigated in the rabbit in vivo and in the isolated blood-perfused rabbit lung. In vivo, the decrease in local blood flow was shown to be dependent on circulating neutrophils. In the isolated blood-perfused lung, inflammation induced by airway instillation of C5a was similar histologically to that seen in vivo and was also accompanied by a decrease in local blood flow. The decrease in blood flow appeared to require circulating neutrophils and was prevented by dazmegral and the platelet-activating factor (PAF) antagonists WEB 2086 and L-659,989. Furthermore, no decrease occurred in aspirin-treated lungs perfused with normal blood, suggesting that the source of thromboxane was lung rather than circulating cells. The decrease in blood flow in inflammation did not appear to be a consequence of hypoxic vasoconstriction. Inflammation in the guinea pig lung was also accompanied by a decrease in local blood flow and was also prevented by dazmegral and PAF antagonists. We conclude that local inflammation in the lung is accompanied by a decrease in blood flow that involves neutrophils and the lipid mediators PAF and thromboxane. We suggest that this form of negative feedback by the neutrophil serves to control the inflammatory response.
Role of echocardiography in the diagnosis and evaluation of severity of mitral and tricuspid stenosis. The presence, severity, and hemodynamic consequences of mitral and tricuspid stenosis can be determined by echocardiographic techniques. In mitral stenosis two-dimensional echocardiographic imaging allows definition of leaflet anatomy and dynamics, subvalvular disease, ventricular function, and involvement of other valves. Spectral and color Doppler echocardiographic techniques permit accurate measurement of transvalvular gradient, determination of functional orifice area, evaluation of associated valvular regurgitation, and assessment of pulmonary artery pressures. These approaches are of recognized clinical value, and they provide additional diagnostic information that is unavailable from clinical assessment alone in a significant number of patients. Compared with available invasive diagnostic standards of reference, echocardiographic data have been found to be comparable in accuracy. In tricuspid stenosis echocardiographic imaging and Doppler techniques provide an assessment of valve morphology and function that should be similarly useful in clinical management decisions, although rigorous comparative studies have not been performed. Currently, carefully done echocardiographic studies are a definitive means of establishing the presence and significance of mitral stenosis and tricuspid stenosis, thereby obviating the need for invasive evaluation in many patients, reducing risk, and potentially decreasing the cost of diagnostic assessment.
Lack of diameter effect on short-term patency of size-matched Dacron aortobifemoral grafts. This study examined the relationship between graft diameter and subsequent patency in 79 patients who received Dacron aortobifemoral bypass grafts for aortoiliac occlusive disease between 1985 and 1989. Sixty-five percent of these patients were men, 25% were diabetic, and 94% were smokers, with an average age of 62 years. Patients were followed for a mean interval of 24 months. Life-table survival was 92% at 3 years. All surviving patients showed "significant" postoperative improvement by use of Society for Vascular Surgery/International Society for Cardiovascular Surgery combined clinical and vascular laboratory criteria. There were three early and five late graft thromboses. Primary and secondary life-table patencies were 85% and 92%, respectively, at 3 years. Dacron bifurcation grafts were selected to match the size of native arteries. Patients receiving small diameter grafts, defined as 12 mm (n = 9) and 14 mm (n = 39), were compared with patients receiving large diameter grafts of 16 mm (n = 26) and 18 mm (n = 5). Small diameter grafts were more likely to be used in women (p less than 0.01), but patient groups were otherwise comparable with respect to age, smoking history, diabetes, outflow status, operative indications, type of proximal anastomosis (end-to-end or end-to-side), location of distal anastomosis (common femoral vs deep femoral), type of graft construction (knitted vs woven), and functional result. Graft diameter did not influence life-table patency, which was 84% for small and 87% for large diameter grafts at 3 years (p = 0.74). Furthermore, none of the other variables listed above influenced graft patency.
Amnesia following damage to the left fornix and to other sites. A comparative study. Two memory-impaired patients, who had suffered damage to the left or both fornix columns during removal of a ventricular cyst, were compared with 3 others having left-sided hippocampal or thalamic lesions, and with normal controls. The tests used were nonverbal--scene recognition, delayed matching-to-sample and concurrent pattern and object discrimination learning. The last two are differentially sensitive to fornix transection and to hippocampal or thalamic ablations in monkeys; however, the patients with fornix damage did not show a distinctive pattern of impairment. The reasons for this discrepancy are discussed. The study adds to the evidence that fornix transection can cause wide-ranging memory disturbances in man.
DNA ploidy analysis of effectiveness of radiation therapy for cervical carcinoma. Cellular DNA content from 30 patients with cervical carcinoma was determined using flow cytometry before and after radiation therapy (RT). The authors attempted to correlate changes in DNA content, tumor response to RT, and post-RT pathologic findings. Before RT, tumors from eight of 30 patients (26.7%) were diploid or near-diploid; tumors from 22 patients (73.3%) were aneuploid. After RT, diploid or near-diploid tumors were found in 23 patients (76.7%), and aneuploid tumors were observed in seven patients (23.3%). Aneuploidy disappeared in 15 of the patient tumors, and complete tumor response (CR) was observed in 13 of these 15 patients (86.7%). Pathologic examinations were negative in 12 of 15 cases and suspicious in one of 15 cases. Of the seven patients whose tumor aneuploidy did not change after RT, CR was observed in only two (28.7%). Pathologic examinations were positive in five of seven cases and suspicious in one of seven cases. The CR for the 22 patients with pre-RT aneuploid tumors was 15 of 22 (68.2%); the CR for the eight patients with pre-RT diploid tumors was two of eight (25%, P less than 0.01). From these data the authors conclude there is a direct correlation between DNA content and radiosensitivity in cervical carcinoma. Aneuploid tumors from these patients were more radiosensitive than diploid tumors, and they patients had a better clinical tumor response and improved pathologic findings.
Enhanced GABAergic inhibition preserves hippocampal structure and function in a model of epilepsy. Extensive electrical stimulation of the perforant pathway input to the hippocampus results in a characteristic pattern of neuronal death, which is accompanied by an impairment of cognitive functions similar to that seen in human temporal lobe epilepsy. The excitotoxic hypothesis of epileptic cell death [Olney, J. W. (1978) in Kainic Acid as a Tool in Neurobiology, eds. McGeer, E., Olney, J. W. & McGeer, P. (Raven, New York), pp. 95-121; Olney, J. W. (1983) in Excitotoxins, eds. Fuxe, K., Roberts, P. J. & Schwartch, R. (Wenner-Gren International Symposium Series, Macmillan, London), Vol. 39, pp. 82-96; and Rothman, S. M. & Olney, J. W. (1986) Ann. Neurol. 19, 105-111] predicts an imbalance between excitation and inhibition, which occurs probably as a result of hyperactivity in afferent pathways or impaired inhibition. In the present study, we investigated whether the enhancement of gamma-aminobutyric acid (GABA)-mediated (GABAergic) inhibition of neurotransmission by blocking the GABA-metabolizing enzyme, GABA transaminase, could influence the histopathological and/or the behavioral outcome in this epilepsy model. We demonstrate that the loss of pyramidal cells and hilar somatostatin-containing neurons can be abolished by enhancing the level of synaptically released GABA, and that the preservation of hippocampal structure is accompanied by a significant sparing of spatial memory as compared with placebo-treated controls. These results suggest that enhanced GABAergic inhibition can effectively block the pathophysiological processes that lead to excitotoxic cell death and, as a result, protect the brain from seizure-induced cognitive impairment.
Cortical blindness in children: a study of etiology and prognosis. Thirty-four children (20 boys, 14 girls) with congenital and acquired cortical blindness were analyzed for visual outcome in relation to etiology, visual evoked potentials, electroencephalography, and cranial computed tomography. All 7 children with congenital cortical blindness remained blind on subsequent examination. Of the 27 children with acquired blindness, 16 (59%) had poor visual outcome. Poor visual outcome occurred in those with cardiac arrest, hypoxia, status epilepticus, intracranial hemorrhage, cerebral thrombosis, and head trauma. Good visual outcome occurred in children with hypotensive episodes after cardiac surgery. Of the 12 children with recovery of vision, the interval from acute loss of vision to partial or total recovery was 2 weeks to 5 months. Seven children had complete recovery of vision with no residual visual field defect. The majority of children (87%) had focal or multifocal spike-and-waves and slow sharp-wave discharges on electroencephalography. None had photic recruitment response or occipital spike-and-wave discharges. Flash visual evoked potential studies performed during acute episodes of cortical blindness documented 11 with absent response, 10 with bilateral increases in latency, and 6 with normal responses. There was no correlation between normal visual evoked potentials and a good visual outcome. Only 2 of 6 children with normal responses had normal vision. Abnormal or absent responses are more predictive of a poor recovery of vision because only 3 of 21 (14%) had normal vision on subsequent examination. Abnormal electroencephalographic findings with focal or multifocal spike-and-wave discharges or cerebral atrophy on cranial computed tomography are also poor prognostic signs.
Factors affecting ability to resume oral nutrition in the oropharyngeal dysphagic individual. Successful oral intake of nutrition depends not only on the patient's ability to swallow efficiently and safely but also a number of cognitive, neurolinguistic, and behavioral variables. This paper reviews these competencies as they are integrated into the act of oral feeding and describes the types of disorders that affect these abilities. Methods of evaluating and treating the abilities needed for successful oral intake are described.
Recurrent abortion and the diagnosis of Wilson disease. We describe the first patient with Wilson disease and recurrent abortion who was effectively treated with oral zinc for both conditions. Between the ages of 21-26, this patient experienced seven successive unexplained abortions. At age 27, neurologic signs and liver function disturbances appeared. Wilson disease was diagnosed when Kayser-Fleischer rings were detected in the cornea. Decoppering therapy was instituted with zinc sulfate per os. By the age of 31, hepatic and neurologic signs had vanished. The patient conceived, and after an uncomplicated eighth pregnancy she delivered her first healthy child. Two years later, a ninth pregnancy was equally successful. The chance that Wilson disease may be the cause of recurrent abortion is small. However, because the disease is fatal if left untreated and because it is an underdiagnosed disease, we recommend screening for Wilson disease in cases of unexplained recurrent abortion when family history demonstrates consanguinity or neurologic, psychiatric, and/or liver disorders. A strategy to this end is proposed.
Ki-67 immunostaining in node-negative stage I/II breast carcinoma. Significant correlation with prognosis. Prognostic predictors for node-negative breast carcinoma have not been clearly established. Immunostaining with Ki-67 antibody was performed on frozen sections of histologically proved node-negative breast carcinomas from 42 patients to examine its prognostic value and its association with other clinicopathologic and biochemical parameters, i.e., patient age and tumor size, histologic type, nuclear grade, mitotic rate, presence of vascular or lymphatic invasion, DNA ploidy, percentage of cells in S-phase, estrogen content, and c-erbB-2 amplification. Thirty-seven of the 42 tumors showed immunoreactivity with Ki-67 antibody in 1% to 55% of the tumor cells. A strongly significant correlation was observed between Ki-67 staining percentage and, respectively, nuclear grade, age, and mitotic rate. Nuclear grade 1 (the most anaplastic) tumors showed a significantly higher median percentage of cells stained (median, 14; range, 3 to 40) compared with nuclear grade 3 tumors (median, 0.5; range, 0 to 8). Thirteen patients developed recurrence; six of them died of disease. On univariate analysis, both 5-year disease-free and overall survivals were strongly associated with percentage of cells stained with Ki-67 antibody. Our results suggest that Ki-67 immunostaining correlates well with nuclear grade and clinical outcome in node-negative breast carcinoma. Because of small sample size analyzed in this study we were unable to do multivariate analysis. Therefore, further studies with larger number of cases are needed to determine whether tumor proliferative activity determined by Ki-67 immunostaining is an independent prognostic parameter or it merely reflects histopathologic features such as nuclear grade or mitotic activity.
A forensic application of DNA typing. Paternity determination in a putrefied fetus. Using minisatellite DNA probes that hybridize to a variable number of tandemly repeated loci, an individual-specific DNA fingerprint can be determined. In the case reported here, we succeeded in extracting high-molecular-weight DNA from a 3-month-old fetus discovered during the autopsy of a murdered 28-year-old pregnant woman reported missing 10 days earlier. The results of analysis of restriction-fragment-length polymorphisms showed that all bands present in the fetus's pattern, but absent in the mother's, matched only those of the putative father. Thus, the paternity of the victim's husband was ruled out.
Chemotherapy dose intensity correlates strongly with response, median survival, and median progression-free survival in metastatic neuroblastoma We examined the efficacy of five commonly used drugs, teniposide (VM26), cisplatin (CDDP), cyclophosphamide (CPM), doxorubicin (DOXO), and vincristine (VCR) in a retrospective analysis of 44 clinical trials of induction chemotherapy for stage IV neuroblastoma patients newly diagnosed at older than 1 year of age. Dose intensity (DI) of each drug was calculated as milligrams per square meter per week. Linear regression analyses showed that the Dls of VM26 and CDDP had the greatest influence on clinical outcomes (ie, proportion of major response, median survival, and median progression-free survival [PFS]), while those of CPM and DOXO were less significant. VCR had no influence on the three clinical end points. Although many protocols extended treatment to more than 1 year, none of these end points correlated positively with the duration of therapy. Twenty-one weeks appeared adequate for achieving superior response, median survival, and median PFS. These results suggest that maximal dose intensification of selective drugs over a short duration may improve the outcome of patients with poor-risk neuroblastoma.
Major amputations done with palliative intent in the treatment of local bony complications associated with advanced cancer. Palliative amputations were performed on 11 patients (7 men, 4 women) with disseminated disease to control local bony complications. The average patient age was 54 years (range 14-78 years). The primary diseases were melanoma/sarcoma (seven patients) and carcinoma (four patients). All had pain; eight had intractable pain that could not be controlled by analgesics. All 11 patients had additional severe local complications, which included recurrent pathological fracture (4), sepsis (2), hemorrhage (2), radiation necrosis (2), and iliofemoral thrombosis secondary to tumor (1). Previous attempts of palliation had been made in all 11 patients, and 8 had undergone previous operative procedures (5 had undergone two or more) prior to amputation. Three anterior hemipelvectomies, five posterior hemipelvectomies, two hip disarticulations, and one forequarter amputation were performed. All patients survived the surgery, and there were no intraoperative complications. All patients received dramatic relief of pain. Postoperative complications included two cases of flap necrosis and two infections; all resolved satisfactorily. The six patients who were nonambulatory before surgery ambulated postoperatively, and two eventually ambulated with a prosthesis. Six of 11 patients survived 1 year or longer, with a median postoperative survival period of 13 months (average 16 months). Although major amputations are viewed at times as offering little to already-compromised patients, they can improve dramatically the quality of life in selected patients.
Confirming the theoretical structure of the McGill Pain Questionnaire in acute clinical pain. Based upon a tripartite theoretical model of pain, the Pain Rating Index (PRI) of the McGill Pain Questionnaire (MPQ) continues to be one of the most frequently used instruments to measure clinical pain. Although a number of exploratory factor analytic studies have failed to consistently support the theoretical structure of the instrument, one previous confirmatory factor analytic study of chronic pain did statistically support the a priori model. Because it has been suggested that acute pain may not involve the same dimensions as chronic pain, this study provided a direct test of the theoretical structure of the MPQ through multi-sample confirmatory factor analysis (CFA) using data provided by women experiencing pain during labor (n = 185) and women experiencing acute postoperative pain (n = 192). Results of the LISREL CFA analysis indicated that the a priori, 3-factor, oblique model originally proposed by Melzack provided the most parsimonious representation of the data across the 2 samples of acute pain.
The physician's responsibilities: residua and sequelae. Cardiologists assuming responsibility for adults with congenital heart disease must have knowledge of electrophysiologic, valvular (native valves), prosthetic (valves, patches and conduits), ventricular (especially chamber function), vascular (especially elevated pulmonary vascular resistance) and noncardiovascular residua and sequelae. Acquired cardiac and noncardiac diseases coexist in older adults with postoperative congenital heart disease and add to the physician's responsibilities.
The mini-grommet and tympanosclerosis. One hundred and sixteen children with otitis media with effusion underwent myringotomy and insertion of a conventional pattern of Shah grommet in one ear and the much smaller Mini Shah grommet in the other. Close observation post-operatively determined the comparative rate of extrusion, recurrence of effusion, and of onset and degree of tympanosclerosis. At one year review, the Mini Shah shows a significantly earlier extrusion and a greater tendency to recurrence of otitis media with effusion. However, this is compensated by a decreased incidence of tympanosclerosis and reduced severity in those affected. This tends to support the view that shear forces produced by heavier patterns of ventilation tube promote tympanosclerosis.