The significance of fetal myocardial and skeletal muscle function as a factor affecting its viability

Histologic study of the heart and functionally active zones of skeletal muscles of the lower limbs of fetuses and newborns (71 cases) is undertakes to distinguish the factors affecting the viability of the fetus (new-born) and detect the total-system muscle tissue involvement after the general morphogenetic mechanism. The basic criteria of a pathological process caused by capillarotrophic myocardial insufficiency are dystrophy, necrosis, and sclerosis. Various forms of nonspecific prenatal myopathy were detected in the skeletal muscles; they were combined with symptoms of chronic myocardial hypoxia. A relationship between cardiovascular abnormalities and intrauterine and neonatal death is revealed.     

Assembly and function of the actin cytoskeleton of yeast: relationships between cables and patches

Actin in eukaryotic cells is found in different pools, with filaments being organized into a variety of supramolecular assemblies. To investigate the assembly and functional relationships between different parts of the actin cytoskeleton in one cell, we studied the morphology and dynamics of cables and patches in yeast. The fine structure of actin cables and the manner in which cables disassemble support a model in which cables are composed of a number of overlapping actin filaments. No evidence for intrinsic polarity of cables was found. To investigate to what extent different parts of the actin cytoskeleton depend on each other, we looked for relationships between cables and patches. Patches and cables were often associated, and their polarized distributions were highly correlated. Therefore, patches and cables do appear to depend on each other for assembly and function. Many cell types show rearrangements of the actin cytoskeleton, which can occur via assembly or movement of actin filaments. In our studies, dramatic changes in actin polarization did not include changes in filamentous actin. In addition, the concentration of actin patches was relatively constant as cells grew. Therefore, cells do not have bursts of activity in which new parts of the actin cytoskeleton are created.     

The intubating laryngeal mask. II: A preliminary clinical report of a new means of intubating the trachea

To determine the effect of anterior cruciate ligament (ACL) reconstruction on symptoms of pain and instability in patients with chronic ACL insufficiency who had previously undergone meniscectomy, we reviewed a series of 21 symptomatic, previously meniscectomized patients with chronic ACL deficiency (average age, 31 years). Arthroscopically assisted intra-articular ACL reconstruction using a middle, one-third patella-tendon autograft was performed in all cases. All patients had radiographic evidence of degenerative changes before ACL reconstruction. The average time from meniscectomy to ACL reconstruction was 6.6 years. Preoperative and postoperative range of motion, stability, and subjective evaluations were compared. Follow-up averaged 37.4 months (range, 24 to 67 months). Physical examination and postoperative KT-1000 side-to-side measurements revealed three patients (14%) with pathological ligament laxity. One patient had a 2+ Lachman, a 2+ pivot shift, and > 5 mm difference on KT-1000 maximum manual test, and two patients had a 1+ Lachman and a 1+ pivot shift. Range of motion measurements taken at follow-up were not significantly different from preoperative measurements (extension, P = .14; flexion, P = .46). Subjectively, all items on a panel of 15 visual analog scales were improved, but intensity of pain and instability were significantly improved after statistical analysis (P < .05). This review suggests that symptoms of pain and instability in patients with chronic ACL deficiency who have previously undergone meniscectomy can be improved by ACL reconstruction if objective stability is obtained.     

Nutritional strategies for promoting fat utilization and delaying the onset of fatigue during prolonged exercise

With increasing human age (20-80 years), the electroencephalogram (EEG) dose requirement for the intravenous anesthetic thiopental decreases approximately 10% per decade of life. The goal of this study was to compare the dose required to attain isoelectric EEG in young (4-5 month) vs. aged (24-25-month) Fischer 344 rats. One second isoelectricity was found to be an endpoint where minimal cardiorespiratory depression occurred. The effects of age, infusion rate, and repeated administration were examined in nine young and nine old rodents. Thiopental dose requirement increased with increasing infusion rates. Repeated administration at two-day intervals did not demonstrate tolerance to thiopental. No difference in thiopental dose requirement was detected in the young vs. elderly rats. In a separate group of five young and five old rats, thiopental plasma, brain, heart, and CSF concentrations were measured when five seconds of EEG isoelectricity was achieved: no consistent differences were noted. The rat may not be an appropriate model to investigate acute age-related anesthetic effects in humans, because cardiovascular changes with age are dissimilar between species.