123rc/medical_text huggingface dataset:
The role of the iliolumbar ligament in the lumbosacral junction. The biomechanical function of the iliolumbar ligament in the human lumbosacral junction was investigated by analyzing the three-dimensional movements of the whole lumbar and lumbo-sacral-ilium specimens. The experiment was repeated in the following three conditions: 1) intact iliolumbar ligament, 2) right iliolumbar ligament transected, and 3) bilateral iliolumbar ligaments transected. The representative values of the increased motions, compared with intact, after transection of the bilateral iliolumbar ligaments were 1.7 degrees (23%) in flexion, 1.1 degrees (20%) in extension, 0.3 degrees (18%) in axial rotation, and 1.2 degrees (29%) in lateral bending. The most restricted motion governed by the iliolumbar ligament in the lumbosacral junction was lateral bending. The bilateral iliolumbar ligament specimen could restrict flexion and extension of the lumbosacral junction, but the unilateral iliolumbar ligament preparation alone could not restrict these motions. The iliolumbar ligament also had the function of restricting the rotational movement of the lumbosacral junction.
Protein synthesis required to anchor a mutant p53 protein which is temperature-sensitive for nuclear transport. The p53 protein is rendered temperature-sensitive by a point mutation. Rat cells transformed by this mutant p53 and an activated ras oncogene grow well at 37 degrees C but cease DNA synthesis and cell division when shifted to 32 degrees C. Immunostaining demonstrates that the mutant p53 protein is in the nucleus of the arrested cells at 32 degrees C but in the cytoplasm of the growing cells at 37 degrees C. This is the first example of a protein which is temperature-sensitive for nuclear transport. The translocation from cytoplasm to nucleus and vice versa occurs 6 h after temperature shift and is coincident with the inhibition of DNA synthesis; transport from cytoplasm to nucleus does not require protein synthesis. Remarkably, inhibition of protein synthesis at 37 degrees C also results in the rapid appearance of mutant p53 in the cell nucleus. These results suggest the presence of a short-lived protein responsible for holding p53 in the cytoplasm at 37 degrees C but not at 32 degrees C. Analysis of a non-temperature-sensitive mutant p53 protein shows that its cytoplasmic location is sensitive to protein synthesis inhibitors but not to temperature.
Neonatal repair of tetralogy of Fallot with and without pulmonary atresia. Our experience with the arterial switch operation for transposition of the great arteries has confirmed the attainability of excellent results with elective neonatal surgery. Up to this time, we have repaired tetralogy of Fallot during the neonatal period only when symptoms, either severe persistent cyanosis or cyanotic spells, have been present. This review assesses the results of such nonelective neonatal correction of tetralogy between 1973 and 1988. Twenty-seven neonates with either symptomatic tetralogy of Fallot or symptomatic tetralogy of Fallot with valvar pulmonary atresia underwent repair. Mean age at repair was 8 +/- 8.4 days and mean weight was 3.0 +/- 0.7 kg. Unsatisfactory palliative shunts had previously been placed elsewhere in four patients. Twenty-five transannular patches and two conduits were used for reconstruction of the right ventricular outflow tract. There were five deaths in the hospital, three of which were due to avoidable technical problems. All deaths occurred in patients with pulmonary artery (Nakata) index less than 150 mm2/m2. One premature child weighing 2.3 kg displayed an absent pulmonary valve-like syndrome after repair and died late of respiratory complications caused by aneurysmal branch pulmonary arteries. Actuarial survival at 5 years was 74%. There was a single rapidly declining hazard phase for death, with the hazard approaching zero at 1 1/2 years after repair. Actuarial freedom from need for reoperation was 76% at 5 years. Postoperative catheterization of 15 long-term survivors showed right ventricular pressure less than 70% systemic in 13 cases. All patients are symptomatically well and functioning in sinus rhythm 1 to 15 years after repair (mean, 5 +/- 4 years). This experience with neonates with symptoms suggests that, if mortality is lower in the absence of symptoms, elective repair of tetralogy of Fallot could be reasonably undertaken during the first months of life.
Oncolytic effects of fatty acids in mice and rats. Intrahepatic implants of M114 carcinoma in B6D2F1/J mice were treated by intraperitoneal injection of 30 mg sodium caprylate (octanoate), and implants of Nb2 lymphoma in Nb rats were treated with 300 mg tricaprylin orally. After 4-11 h extensive damage to tumor cells was evident microscopically whereas liver cells were unaffected. Tumors in mice treated once daily from the fourth to eighth day after implantation were obliterated. Subcutaneous implants of hepatoma Nb10L in Nb rats treated transdermally with a caprylic acid preparation underwent similar damage. Fatty acids can cause lysis of tumor cells with little damage to normal tissue in certain situations. This action is not related to mitotic activity and represents a novel mode of antitumor action.
Graft stenosis: justification for 1-year surveillance. In all, 412 femorodistal grafts (femoropopliteal and femorocrural), performed between 1984 and 1988, have been prospectively studied at 6 weeks and 3, 6, 9 and 12 months after operation and at intervals of 6 months thereafter by duplex scanning and intravenous digital subtraction angiography. The overall incidence of stenoses was 16 per cent (femorocrural 20 per cent, femoropopliteal 15 per cent). All stenoses were detected in the first year after operation and none occurred after this. Twenty-four non-haemodynamically significant stenoses were not treated but were followed at intervals of 3 months. Forty-two haemodynamically significant stenoses were detected and secondary procedures were performed in 30 grafts at a mean of 8 months after surgery. Thirteen had percutaneous balloon dilatation and six (46 per cent) remain patent at a mean follow-up of 22 months. Two grafts which occluded within 30 days and three which restenosed at a mean of 8 months had tertiary procedures. Seventeen grafts were surgically revised, nine with patch grafts and eight with bypass grafts. Eleven of these remain patent at a mean follow-up of 30 months. One occluded immediately and three occluded late. Two grafts which restenosed at a mean of 19 months had successful tertiary procedures. In total, seven grafts had tertiary procedures (two had balloon dilatation and five had surgery) and six of these remain patent at a mean follow-up of 13.5 months. In conclusion, 37 procedures have been performed on 30 grafts, of which 23 (77 per cent) remain patent at a mean follow-up of 12 months. Approximately one-quarter of femorodistal grafts will develop graft-related stenoses and graft surveillance is worthwhile, but only for the first year after operation.
Intraocular lens complications. The authors implanted intraocular lenses (IOL) in 780 eyes and considered complications of this surgery, dividing the complications into intraoperative and postoperative, the latter early and late. The most frequent intraoperative complications were: hyphema, vitreous injury, pupil deformation with an IOL in the anterior chamber (AC), and hyphema and corneal lesions with an IOL in the posterior chamber (PC). Among the early postoperative complications of an IOL in the AC the authors noticed striate keratopathy and uveal flare and postoperative transitory ocular hypertension and striate keratitis with an IOL in the PC. Moreover, in late postoperative complications in AC implantation they observed: cystoid macular edema, bullous keratitis, retinal detachment, late uveitis, opacification of posterior capsule, eccentric displacement of the IOL, and less frequently, cystoid macular edema in PC implantations. The authors prefer IOL implantation in the PC after extracapsular cataract extraction, since this surgery causes less problems in the cornea, vitreous, and retina.
Easy dissection of hard and thickened pericardium on constrictive pericarditis. The keys to successful pericardiectomy for constrictive pericarditis are early operation and as complete a pericardiectomy as possible. With the high-speed burr it is easy and safe to dissect the calcified pericardium and define the epicardium even in a small operative field such as the inferior or posterior portion of the heart. This method has the important ability to perform very complete pericardiectomy.
Reconstruction of the severely atrophic edentulous mandible by means of autogenous bone grafts and simultaneous placement of osseointegrated implants. A method of reconstructing the severely atrophic mandible that simultaneously provides additional strength and the ability to house osseointegrated implants is presented. The performance of the procedure from an external approach minimizes the possibility of oral contamination and, therefore, infection. The procedure has been performed on 10 patients, with a longest follow-up of 3 years. A 93% success rate has been achieved, and bone resorption at the implant sites has thus far been negligible. Prosthetic rehabilitation has been done in 9 of the 10 cases; 3 have been tissue-supported prostheses, and 6 have been completely implant-supported prostheses.
Preoperative aspirin therapy and reoperation for bleeding after coronary artery bypass surgery. We performed a case-control study to estimate the relative risk of reoperation for bleeding in coronary artery bypass graft patients who had taken aspirin within the 7 days preceding surgery. Comparison of 90 cases of reoperation with 180 matched control subjects gave an estimated odds ratio for reoperation of 1.82 (95% confidence interval, 1.23 to 3.32). Although their preoperative coagulation values were similar, cases used significantly more whole blood (cases, 9.5 +/- 5.2 units; control subjects, 3.0 +/- 2.0 units; median +/- interquartile range), packed red blood cells (cases, 2.1 +/- 4.0 units; control subjects, 0.9 +/- 2.0 units), and platelets (cases, 12.2 +/- 12.0 units; control subjects, 2.9 +/- 4.0 units) than control subjects. Cases had intensive care unit stays of 4.7 +/- 5.7 days (mean +/- SD) vs 2.1 +/- 1.9 days for control subjects and postoperative hospitalizations of 10.9 +/- 8.2 days vs 7.0 +/- 3.2 days for control subjects. We conclude that aspirin exposure within 7 days before coronary bypass surgery is associated with an increased rate of reoperation for bleeding and that reoperation is associated with large increases in transfusion requirements and intensive care unit and hospital stays.
Phenotypic heterogeneity of spinal muscular atrophy mapping to chromosome 5q11.2-13.3 (SMA 5q). We made phenotypic analysis of 14 families with spinal muscular atrophy (SMA) linking to chromosome 5q11.2-13.3 (SMA 5q), and 2 that may not map to this locus, to assess clinical symptoms among SMA families known to result from mutation at the identical gene/locus. Although the current number of families is still small, the correlation of clinical phenotype and molecular genotype supports 2 observations. First, SMA mutations at the 5q locus present with a broad continuum of clinical abnormalities, and 2nd, the single clearly unlinked family presents with an unusual phenotype characterized by relatively late onset and early death. Thus, there are as yet no unambiguous cases of typical SMA families that are clearly unlinked to the locus at 5q-ie, no clear cases of nonallelic heterogeneity. Analysis of SMA 5q families supports the view that, with certain exceptions, there is little phenotypic intrafamilial variability. When families were ranked by severity of disease there was a strong correlation with age of onset. Onset within the 1st few months was associated with early death, but not in all cases. With rare exception, onset after 1 year of age was associated with less severe disease and greater longevity.
Clostridium difficile--a common and costly colitis. Clostridium difficile infection manifests as a self-limiting diarrhea, protracted colitis, or toxic pseudomembranous colitis. The incidence of C. difficile in a 514-bed community hospital was studied retrospectively; 155 patients of a total 18,262 admitted during 1988 were identified with C. difficile as an admitting or subsequent diagnosis. The method of diagnosis, mode of therapy, and related costs were analyzed. We have determined that education, with an emphasis on pathogenesis and prevention, is necessary to reduce the incidence in the hospital and the cost to the patient.
Efficacy of biofeedback training in improving faecal incontinence and anorectal physiologic function. The efficacy of biofeedback treatment on faecal incontinence and anorectal function was evaluated in eight patients with faecal incontinence treated with biofeedback training and medical therapy. Outcome and anorectal function were compared with nine faecal incontinent patients who received medical therapy alone. Three month follow up showed that 50% of patients in the biofeedback plus conventional treatment group and 56% of those treated conventionally only had improved. One year follow up showed that 13% in the biofeedback group were free of soiling and an additional 25% had improved. The results were similar in the conventionally treated group--11% were free of soiling and an additional 44% improved. Anal pressures at rest and squeeze, the rectal distension volume that induced sustained inhibition of both the external and internal anal sphincter, and continence to rectally infused saline were significantly reduced in both groups of patients compared with controls (p less than 0.05). Biofeedback treatment had no effect on these abnormal anorectal functions in either patients who improved or those who did not. The improvement in faecal incontinence was probably due to medical intervention or regression of symptoms with time, or both, and not the result of biofeedback training.
Noninvasive discrimination of right atrial ectopic tachycardia from sinus tachycardia in "dilated cardiomyopathy". Right atrial ectopic tachycardia (RAET) with secondary cardiac dysfunction can be difficult to differentiate from primary dilated cardiomyopathy (CMP) with sinus tachycardia. In an attempt to separate RAET from CMP by noninvasive testing, routine surface electrocardiograms (EGGs), 24-hour ambulatory ECGs (Holter monitors), and echocardiograms of patients with RAET (n = 34) and CMP (n = 33) were reviewed. RAET atrial rates were significantly faster than CMP rates on the resting ECG and on Holter monitoring; 12 of 33 patients with RAET had resting ECG rates greater than 150% of predicted normal values for age but none of 32 patients with CMPs had resting ECG rates in this range. Mean P wave axis in the horizontal plane was more posterior in patients with RAET and was less than 0 degrees (negative in lead V2) in 8 of 29 patients with RAET but in 1 of 33 patients with CMP. Second-degree atrioventricular (AV) block was observed in 12 of 33 patients with RAET but in none of 33 with CMP. Shortening fraction less than 10% was found in 13 of 33 individuals with CMP but in only 1 of 27 with RAET. We conclude that noninvasive studies can help identify RAET among patients with poor functioning hearts and right atrial tachycardia.
Neurologic complications in chronic renal failure: a retrospective study. We have retrospectively examined 324 patients with chronic renal failure and evaluated the probable underlying causes of neurologic complications, laboratory data and therapeutic interventions. The common neurologic problems in our patients were alterations in consciousness (40.7%) and convulsions (35.1%). When BUN concentration was above 135 mg/dl and creatinine clearance was below 8 m/min/1.73 m2, alteration of consciousness was observed and when BUN concentration was 200 mg/dl and creatinine clearance was below 7 m/min/1.73 m2, abnormal convulsives appeared. Changes in deep tendon reflexes and pathologic reflexes were associated with hypertension. All of the patients with cortical atrophy using computerized cranial tomography aluminum hydroxide at least for 18 months, and six of them had hemodialysis. Fourteen patients who underwent dialysis developed convulsions and were thought to have disequilibrium syndrome. These findings are consistent with the suggestion that the metabolic and biochemical derangements associated with CRF may be particularly detrimental to the still developing CNS of the child.
Reversible hearing loss from cerebellopontine angle tumors. We report two patients who presented with a dramatic recovery from severe sensorineural hearing loss after total surgical removal of cerebellopontine angle tumors (meningioma and jugular foramen neurinoma). The factors that differentiate these "non-acoustic tumors" in relation to the prognosis for hearing are discussed. A surgical approach that maintains the labyrinthine structure and preserves the arachnoid membrane of the superior cerebellopontine angle cistern during tumor removal is stressed.
Comparison of i.m. ketorolac trometamol and morphine sulphate for pain relief after cholecystectomy. I.m. ketorolac trometamol 30 mg was compared with morphine sulphate 10 mg after cholecystectomy in a double-blind, multiple dose, randomized study of 100 patients. Assessments of pain were made immediately after operation (day 1), and the next morning (day 2). Pain intensity (verbal response score and visual analogue scale) was recorded before injection and then over a 6-h period. Pain relief was assessed also. The effect of ketorolac on operative blood loss and platelet function was examined. Time to commencing oral intake and the duration of administration of i.v. fluids were recorded. Adverse events were noted. Ketorolac produced significantly less analgesia than morphine on day 1, but on day 2 the two drugs produced a similar effect. Blood loss was not increased by ketorolac, although platelet function was impaired. Repeated i.m. administration of ketorolac did not produce any serious adverse effects.
Clinical and electrophysiological characteristics of ventricular tachycardia in children with normal hearts. Characteristics of 18 patients with clinical ventricular tachycardia (VT) and normal hearts documented by physical examination, echocardiography, and angiocardiography were analyzed. There were 13 males and 5 females, aged 1 to 16 years (mean +/- SD, 9.7 +/- 4.8 years). Six patients had hemodynamic instability during VT and the other 12 patients were hemodynamically stable. Two patients (11%) presented with sustained VT and 16 (89%) with episodes of nonsustained VT at varying intervals (3 of 16 with repetitive monomorphic VT). Among 14 patients on whom exercise tests were performed, seven had exercise-induced VT. During electrophysiologic studies, VT was induced in 16 of 18 (89%) (in 13 patients with morphology identical to clinical VT). VT was induced by programmed stimulation (single, double, and burst stimulation of the right atrium or right ventricular apex during sinus rhythm or during pacind for eight beats) in 5 of 18 (28%) patients; with isoproterenol, VT was aggravated spontaneously in 6 of 15 (40%) patients; and during stimulation VT was induced in 8 of 15 (53%) patients. Among patients whose VT was not induced during programmed stimulation, VT was induced with the addition of isoproterenol in 11 of 12 (92%). All 14 patients in follow-up are in stable condition, seven patients with medication and seven without medication. Pediatric patients with normal hearts and clinically detected VT usually have VT induced by programmed stimulation, either with or without isoproterenol stimulation.
Substance abuse and cerebral blood flow. OBJECTIVE AND METHOD: This paper reviews acute and chronic effects of drugs of abuse on cerebral blood flow (CBF) and metabolism and their clinical significance. The most important source of information for the review is human research reports published in refereed journals. A few animal studies, book chapters, and abstracts that are especially relevant are also included. RESULTS: In humans, ethanol in small doses produces cerebral vasodilation; higher doses induce cerebral vasoconstriction. Chronic alcoholism is associated with reduced CBF and cerebral metabolism. Sedatives and antianxiety drugs lead to global reduction in CBF and cerebral metabolism. Caffeine, even in small doses, is a potent cerebral vasoconstrictor. Cerebral vasodilation is seen immediately after cigarette smoking, but chronic smokers show global reduction in CBF. Changes in CBF after marijuana smoking are variable; both increases and decreases are seen. Chronic marijuana smoking, however, seems to reduce CBF. Most inhalants and solvents are vasodilators; chronic abuse is accompanied by a decrease in CBF. A number of drugs of abuse, including ethanol, amphetamines, cocaine, nicotine, and caffeine-phenylpropanolamine combinations, increase the risk for stroke. Reduction in CBF associated with chronic use of ethanol, nicotine, inhalants, and solvents is at least partially reversible upon abstinence. CONCLUSIONS: Topics for future research include regional brain function, which mediates drug-induced mood changes (euphoria); CBF concomitants of psychological and physiological characteristics that increase addiction potential; changes in CBF that accompany withdrawal syndromes; mechanisms responsible for drug-induced stroke; and effects of functional and organic complications on CBF.
Detection of restenosis after successful coronary angioplasty: improved clinical decision making with use of a logistic model combining procedural and follow-up variables. A prospective study of 111 patients who underwent repeat coronary angiography and exercise thallium-201 scintigraphy 6 +/- 2 months after complete revascularization by percutaneous transluminal coronary angioplasty was performed to assess whether clinical, procedure-related and postangioplasty exercise variables yield independent information for the prediction of angiographic restenosis after angioplasty. Complete revascularization was defined as successful angioplasty of one or more vessels that resulted in no residual coronary lesion with greater than 50% diameter stenosis. Restenosis was defined as a residual stenosis at the time of repeat angiography of greater than 50% of luminal diameter. Restenosis occurred in 40% of the patients. The 111 patients were randomly subdivided into a learning group (n = 84) and a testing group (n = 27). A logistic discriminant analysis was performed in the learning group and the logistic model was used to estimate a logistic probability of restenosis. This probability of restenosis was validated in the testing group. In the learning group of 84 patients univariate analysis of 39 factors revealed 8 factors related to restenosis: recurrence of angina (p less than 0.0001), postangioplasty abnormal finding on exercise thallium-201 scintigram (p less than 0.0001), exercise thallium-201 scintigram score (p less than 0.0001), difference between exercise and rest ST segment depression (p less than 0.001), postangioplasty exercise ST segment depression (p less than 0.001), absolute postangioplasty stenosis diameter (p less than 0.003), postangioplasty exercise work load (p less than 0.03) and postangioplasty exercise heart rate (p less than 0.05).