ABSTRACT
The purpose of this study was to investigate the potential subchronic toxicity of plant sterol esters by a 13-week repeated oral dose in Sprague-Dawley rats. The test article was administered once daily by gavage to male and female rats at dose levels of 0, 1000, 3000 and 9000 mg/kg/day for 13 weeks. At the end of treatment period, 10 rats/sex/group were sacrificed, while six rats/sex in the negative control and highest dose groups were sacrificed after a 4-week recovery period. During the test period, clinical signs, mortality, body weights, food and water consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights and histopathology were examined. Slight decreases in body weight gain were noted at lower doses but were only statistically different from the control animals in the highest dose group. In histopathological examinations, an increase in the incidence of cardiomyopathy with mononuclear cell infiltration was observed in males of the 9000 mg/kg group. Decreased body weight gain and increased incidence of cardiomyopathy observed in the highest dose group were not recovered until the end of the recovery period. There were no adverse effects on mortality, clinical signs, food and water consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, necropsy findings and organ weights in any treatment group. Based on these results, it was concluded that the 13-week repeated oral dose of plant sterol esters resulted in the suppression of body weight gains in both sexes and cardiomyopathy in males at a dose level of 9000 mg/kg/day. The target organ was determined to be heart in males, but not in females. The no-observed-adverse-effect level (NOAEL) was considered to be 3000 mg/kg/day for both sexes.
Subject(s)
Phytosterols/toxicity , Administration, Oral , Animals , Dose-Response Relationship, Drug , Drinking/drug effects , Eating/drug effects , Esterification , Female , Heart Diseases/chemically induced , Male , Organ Size/drug effects , Phytosterols/administration & dosage , Rats , Rats, Sprague-Dawley , Sex Factors , Weight Gain/drug effectsABSTRACT
This study investigated the cocontraction of eight trunk muscles during the application of asymmetric loads to the torso. External moments of 10, 20, 30, 40, and 50 Nm were applied to the torso via a harness system. The direction of the applied moment was varied by 30 degrees increments to the subjects' right side between the sagittally symmetric orientations front and rear. Electromyographic (EMG) data from the left and right latissimus dorsi, erector spinae, external oblique, and rectus abdominus were collected from 10 subjects. The normalized EMG data were tested using multivariate and univariate analyses of variance procedures. These analyses showed significant interactions between the moment magnitude and the moment direction for seven of the eight muscles. Most of the interactions could be characterized as due to changes in muscle recruitment with changes in the direction of the external moment. Analysis of the relative activation levels, which were computed for each combination of moment magnitude and direction, indicated large changes in muscle recruitment due to asymmetry, but only small adjustments in the relative activation levels due to increased moment magnitude.
Subject(s)
Muscle Contraction/physiology , Muscles/anatomy & histology , Muscles/physiology , Adult , Analysis of Variance , Biomechanical Phenomena , Electromyography , Ergometry , Humans , Male , Models, Biological , Multivariate Analysis , Stress, Mechanical , ThoraxABSTRACT
Mucocele of appendix comprises 0.07%-0.3% of the resection of appendix. Three such cases were encountered over the past four years at MMH. Tumor mass could be palpated before operation in two of our cases. The third case was found incidentally during sigmoid cancer resection. Mucocele of the appendix should be differentiated from submucosal lesion such as leiomyoma, lipoma, lymphoma in the cecum or appendiceal abscess. Recent advances of ultrasound, CAT scan as well as angiography have made correct preoperative diagnosis possible, yet literature still shows diverse opinion about its etiology (neoplastic vs. obstructive). Although most authors favor simple appendectomy for the management of this disease, some surgeons still think it should be managed aggressively with colectomy. Rupture of mucocele might result in pseudomyxoma peritonei and possibly a fetal outcome. Avoidance of iatrogenic rupture of appendix is essential. Aggressive removal of accessible masses and implants was suggested in the literature.
