Elasto-optic evaluation of stabile models. Stress concentration

The nutritional quality of rice protein was compared with that of whole egg protein by slope ratio assay. Diets for each food at four levels of protein, 4, 6, 10 and 15% and a protein-free diet were given to male weanling rats of the Sprague-Dawley strain for 21 days. The slopes of the regression lines of the whole egg and rice groups calculated from the changes of body weight (Y in g/21 days) with nitrogen intake (X in g/21 days), including and (excluding) zero protein group were, respectively, Y=27.39 X-12.26 (Y=24.41 X-1.86) and Y = 13.86 X-8.06 (Y = 12.54 X +0.50). Assuming a potency of 100 for the egg protein, the relative potency of rice estimated from body weight gain with nitrogen intake was 51 (51). The values for rice calculated from body water gain and nitrogen retention with nitrogen intake were, respectively, 51 (47) and 46 (44). These values were compared with RNV of several varieties of conventional rice and high-protein rice.     

Delivery of twins

Reconstruction of the nose provides many challenges owing to its differing subunits and varied surfaces. In this article, the nasal anatomy, anesthesia, and some of the reconstructive options available to the dermatologic surgeon are reviewed. These reconstructive options are based on the subunit and depth of the defect. This subunit approach may provide a framework of decision making and options that will help the dermatologic surgeon in reconstruction of defects on this unique anatomic structure.     

Stress concentration at a notch tip in unidirectional metal matrix composites

A method to calculate static stress concentration factors in the fibers at the tip of a rectangular notch in unidirectional metal matrix composites was presented based on the shear lag analysis for a two-dimensional (2-D) model. By using this method, the influences of matrix yielding, width and size of notch, and size of specimen on the stress concentration factors were described. Furthermore, this method was applied successfully to describe the load-COD curve and tensile strength of notched-boron/aluminum and alumina/aluminum composites.     

First-trimester diagnosis of conjoined twins

The binding of levamisole to total plasma proteins of 6 animal species was determined in vitro by equilibrium dialysis. The percentage of bound drug protein was independent of levamisole concentration within the range studied, 5-50 micrograms/ml (ANOVA). Levamisole was bound to a low extent to plasma proteins of each animal species (19.40-25.91%). There were significant differences in the extent of levamisole binding among species (ANOVA). Owing to the low degree of protein binding and the high volume of distribution of levamisole, the variations in protein binding due to different factors would not be of major clinical importance in its therapeutic application.     

Endometriosis in monozygotic twins

OBJECTIVE: To describe the occurrence of endometriosis in monozygotic twins. DESIGN: Postal questionnaire plus confirmation of disease status. SETTING: Twins were recruited via the American Endometriosis Association and the National Endometriosis Society of Great Britain and via British gynecologists. RESULT(S): Fourteen twin pairs were concordant for endometriosis, and two were discordant. Nine pairs of twins had moderate-severe endometriosis. CONCLUSION(S): These findings contribute to the growing body of literature that suggests endometriosis has a genetic basis.     

Multicore disease in twins

Multicore disease in identical twin boys presented in infancy as generalized weakness and torticollis. Motor milestones such as sitting, standing, and running were delayed, although by the age of 6 years marked improvement in muscle strength had occurred. Serum enzymes were normal. Muscle biopsy revealed multifocal areas of decreased oxidative enzyme activity. Ultrastructurally, these areas were characterized by myofilament disruption and Z-band streaming.     

Fetal testing in twins

Mivacurium has a short duration of action because it is rapidly hydrolysed by plasma cholinesterase. There is ongoing controversy concerning the antagonism of mivacurium-induced neuromuscular block, firstly because of its short spontaneous recovery time, and secondly because the metabolism of mivacurium may be inhibited by anticholinesterases. We therefore compared neostigmine and edrophonium reversal of deep and moderate mivacurium-induced blocks. METHODS: After approval by the local ethics committee, 48 ASA class I and II adult patients were investigated during nitrous oxide-fentanyl-thiopental anaesthesia using train-of-four (TOF) stimulation and monitoring of the isometric force of adduction of a thumb. The patients received 0.2 mg/kg mivacurium i.v. Neuromuscular transmission was allowed to recover spontaneously in 10 patients (group SP). In 2 other groups the neuromuscular block was antagonised by administration of 0.04 mg/kg neostigmine (group N5; n = 9) or 1.0 mg/kg edrophonium (group E5; n = 10) when T1 had recovered spontaneously to 5% of control. In two other groups the neuromuscular block was antagonised with the same doses of neostigmine or edrophonium in 10 patients (group N25) and 9 patients (group E25), respectively, when T1 had recovered spontaneously to 25% of control. RESULTS: Neostigmine or edrophonium administered when T1 had recovered spontaneously to 25% of control shortened the recovery time (time from administration of ant-agonist to a T4/T1-ratio of 0.7) significantly from 10.7 +/- 2.2 min (mean +/- SD) in the SP group to 5.1 +/- 2.0 and 5.3 +/- 1.5 min in the N25 and E25 groups, respectively (P < 0.05). The corresponding recovery times in the SP, N5, and E5 groups were 15.9 +/- 2.9, 10.0 +/- 1.9, and 7.7 +/- 2.2 min, respectively. The difference between the SP and E5 groups was significant (P < 0.05). The recovery indices (time from 25% to 75% recovery of T1) of 3.0 +/- 1.3 and 1.7 +/- 0.9 min for the E5 and E25 groups, respectively, were shorter than those of the SP group at 6.1 +/- 2.0 min (P < 0.05). CONCLUSIONS: Two theoretical reasons, the very rapid onset time and the fact that it does not inhibit plasma cholinesterase, suggest edrophonium to be the preferred antagonist of a mivacurium-induced blockade. These two characteristics are reflected in our results: only edrophonium was able to shorten the recovery index significantly and, administered at a profound level of mivacurium-induced neuromuscular block, only edrophonium was successful in shortening recovery time significantly. Therefore, edrophonium should be the anticholinesterase of choice to antagonise a mivacurium-induced neuromuscular block.     

Sarcoidosis in identical twins

Identical twin sisters who developed sarcoidosis at an interval of one year are reported. Case 1. (elder sister) A 22-year-old female was admitted to our hospital for examination of cervical lymph node swelling. Her chest roentgenogram showed bilateral hilar lymphadenopathy and the diagnosis was confirmed histologically by scalene node biopsy. Case 2. (younger sister) In 1987, at age 23, a routine chest roentgenogram showed bilateral hilar lymphadenopathy and the diagnosis was confirmed histologically by transbronchial lung biopsy. The occurrence of sarcoidosis in identical twins suggests that a genetic factor might be involved in the pathogenesis.     

Causes of perinatal mortality in twins

The author analyses perinatal mortality in 244 twin pregnancies. In 80% the twins' Apgare score at birth was 10 to 8 and neonatal mortality in this group 1.26%. The slightly asphyxial group (Apgar 7 to 4) comprised 62 (38.75%) twins and the neonatal mortality in this group was 14.51%. There were 20 (12.5%) severely asphyxial (Apgar 3 or less) twins, their neonatal mortality amounting to 80.0%. Out of 193 twins weighing at birth less than 2500 g, 45 (23.31%) died, while in the twins weighing more than 2500 g there was not a single death. The perinatal mortality of twins up to the 37th week of pregnancy amounted to 17.37% and from the 38th week of pregnancy to 1.22%. The mean duration of pregnancy in twins was 38.1 +/- 2 SD 6.3 weeks. The most frequent cause of death in twins has proved to be immaturity and asphyxia at birth, leading to the development of hyaline membranes (80.0%). Other causes were far less frequent. The author concludes that in the perinatal mortality of twins their vitality at birth (assessed by the Apgar score), birth weight, and the duration of pregnancy play an important role.     

Zygosity and intrauterine growth of twins

Six hundred seventy-eight sonar measurements of the fetal biparietal diameter (BPD) were used to assess the intrauterine growth of 182 twins between 18 and 40 weeks' gestation. These values, as well as the weight and body length at birth, were related to the zygosity, which was determined by sex of the infants, histologic examination of placenta, or blood grouping. The mean BPD of twin 1 was larger than that of twin 2 in both monozygotic and dizygotic pairs throughout the study period (P less than .001). The size of BPD of the dizygotic infants exceeded that of the monozygotic among both twin 1 (P less than .001) and twin 2 (P less than .001). The absolute intrapair differences of birth length and weight were larger among dizygotic than among monozygotic twins. These findings suggest that in late pregnancy a substantial one-way intertwin transfusion among monochorial twins does not occur frequently enough to mask the inherent genetically determined similarity between the twins. The appearance already in the second trimester of the difference in the longitudinally monitored BPD between monozygotic and dizygotic twins suggests that the discrepancy is determined early in gestation.     

The role of oral 1C antiarrhythmic drugs in terminating atrial fibrillation

PURPOSE: To investigate a possible relationship between evisceration and sympathetic ophthalmia. METHODS: Data from Mt. Sinai Medical Center and University Hospitals of Cleveland were collected and histopathologic specimens were reviewed for 51 of 90 patients who underwent evisceration between 1980 and 1996 and who returned for follow-up examinations. Additionally, a survey was sent to members of the American Society of Ophthalmic Plastic and Reconstructive Surgery, the Uveitis Society, and the Eastern Ophthalmic Pathology Society to determine the number of enucleations and eviscerations performed and the documented incidence of sympathetic ophthalmia after evisceration. RESULTS: No clinical or histopathologic evidence of sympathetic ophthalmia after evisceration was found among patients treated at the two medical centers. The collective surveys showed a strong preference for enucleation over evisceration, but did not document evidence of sympathetic ophthalmia after evisceration. CONCLUSIONS: Evisceration is an effective and safe procedure with a low risk for sympathetic ophthalmia.     

Placental pathology in discordant twins

OBJECTIVE: The aim of this study was to evaluate placental abnormalities in relation to birth weight discordance in dichorionic and monochorionic twins. STUDY DESIGN: The maternal charts and placental abnormalities of 147 structurally normal twin pairs with cords labeled at delivery were reviewed. The placental weight belonging to each twin was determined by measuring the length, width, and thickness in each of the two placental disks. Placental weight, chorionicity, infarction, abruptio placentae, decidual vascular abnormality, villous fibrosis and hypovascularity, chronic villitis, and intraplacental thrombi were also assessed. Birth weight was discordant if > or = 20%. The data were analyzed with chi 2 and analysis of variance after log transformation of skewed discordancy values. RESULTS: Of the 147 twin pairs, 99 were dichorionic and 48 monochorionic. Placental weights were known for 91 dichorionic and 40 monochorionic twins. Of the lighter cotwins in dichorionic twin pairs 36.3% (33/91) belonged to the heavier placenta, 49.5% (45/91) belonged to the lighter placenta, and 14.3% (13/91) had an equal share of the placental weight with the heavier sibling (p < 0.05). In 42.4% (42/99) the lighter dichorionic twin had more placental lesions than the heavier twin, in 38.4% (38/99) the same number of lesions were present in both placentas, and in 19.2% (19/99) the heavier twin had more placental lesions. There was linear correlation between percent discordance and number of placental lesions in the lighter twin. In dichorionic twins 18 of the 99 (18.1%) were discordant. In 77.8% (14/18) the lighter twin had more placental lesions than the heavier twin, in 16.7% (3/18) the number of lesions was the same in both, and in 5.6% (1/18) the heavier twin had one more lesion than the lighter twin (p < 0.05). In monochorionic twins, regardless of birth weight discordance, no differences in placental abnormalities were observed. CONCLUSIONS: In dichorionic twins significant birth weight discordance was attributable not to differences in placental weight but to a greater number of placental lesions in the lighter twin than in the heavier twin (p < 0.05). This did not hold true for monochorionic twins.     

Auditory lateralization in monozygotic twins

In an attempt to investigate whether auditory lateralization has a heritable component, 20 monozygotic (MZ) twin pairs were examined with four different dichotic listening tests known to produce reliable right-ear advantages (REAs) in right-handers. Ten twin pairs were concordantly right-handed (MZ-RR), and ten twin pairs were discordant for handedness (MZ-RL). Intraclass correlations for MZ twin pairs were weak or nonexistent for ear advantage, but relatively strong for overall correct scores and mean reaction times, measures unrelated to laterality scores. These results support the hypothesis that auditory lateralization, as measured with dichotic tests, is nongenetic in origin. A comparison of MZ twins and right-handed siblings (n = 20) showed that right-handed siblings exhibited strong REAs, whereas left-handed siblings (n = 20) and MZ twins showed weak or absent REAs, indicating that twins may be atypically lateralized with respect to auditory lateralization.     

Duodenal atresia in dizygotic twins

The authors report duodenal atresia occurring in both members of dizygotic twins who showed no signs of Down's syndrome, and both had normal chromosomal constitutions. They both had the two unlinked end type of atresia in the second portion of the duodenum, and direct end-to-end duodenoduodenostomy was carried out. Their postoperative courses were smooth, and both babies were discharged 32 days after birth. Their mother underwent pituitary adenoma removal and partial parathyroidectomy for multiple endocrine neoplasia (MEN-type I). She had been given hormonal supplement therapy after surgery and became pregnant after exogenous gonadotropin therapy. Environmental factors may be responsible for some cases of duodenal atresia.