Changes in brain memory functions as affected by a constant magnetic field]

OBJECTIVE: The preferred route of delivery for breech presentation has been controversial. We compared the birth weight-specific neonatal mortality of vaginal births to cesarean births in singleton births with breech presentation. METHODS: A total of 371,692 singleton live births with breech presentation were selected for the study from the United States birth cohorts for the years 1989-1991. Differences in birth weight specific mortality were compared using a z-statistic for differences in proportions and by logistic regression. RESULTS: Compared to primary vaginal births, primary cesarean births had significantly lower neonatal mortality for all birth weight groups, despite increased prevalence of fetal malformations in the cesarean as compared with vaginally delivered group. This mortality difference was greatest in the first hour of life. Difference in overall neonatal (less than 28 days) mortality rate ranged from a low of 1.6-fold in the 500-749 g group (726.6 per 1000 vaginal births compared with 456.3 per 1000 cesarean births, P < .001) to as high as about three-fold in the 1250-1499 g group (232.9 per 1000 vaginal births compared to 72.5 per 1000 cesarean births, P < .001). In the group with birth weights over 2500 g, neonatal mortality in the primary vaginal births was 5.3 per 1000 and in the primary cesarean births, 3.2 per 1000 (P < .001). Similarly, repeat cesarean births had significantly lower birth weight-specific neonatal mortality, compared with vaginal births after previous cesarean. CONCLUSION: Singleton live births with breech presentation delivered by cesarean had lower birth weight-specific neonatal mortality as compared with vaginal births.     

The potential use of an extract of aspen bark for enhancing the efficacy of specific treatment methods in experimental malignant neoplasms

The effect of liquid aspen bark extract on the effectiveness of cytostatic and surgical methods of treatment of experimental tumors in mice was studied. The extract was found to raise the antitumorous and antimetastatic effects of the above indicated methods of treatment on the tumor process.     

Calcium Phosphate Microcapsules as Multifunctional Drug Delivery Devices

More challenging active pharmaceutical ingredients are entering the market, spurring the introduction of novel drug delivery strategies that necessitate a paradigm shift from exhausted excipients to materials with combined actions and multiple functionalities. In this study, an inorganic calcium phosphate microparticle with a hollow internal structure is introduced as a biocompatible and multifunctional microcapsule: the template inverted particle (TIP). A robust process is presented to create a unique particle geometry, which is characterized by a particle size of 20 µm and a hollow cavity enclosed by a specially engineered porous shell. This study focuses on the characterization of TIP as an excipient for the design of solid dosage forms. The cavities in the particle centers serve as an encapsulation space, resulting in boosted water uptake capacity of 5.3 cm³ g⁻¹. Benefiting from the material's high wettability and water uptake rates, TIP tablets immediately disperse in the oral cavity. Mechanistic studies reveal a viscoelastic behavior of empty TIP microcapsules in accordance with the Kelvin–Voigt model of a parallel spring-dashpot configuration. The unique particle geometry is maintained during compaction thanks to its exceptional structural integrity. This study demonstrates how multifunctional TIP microcapsules can be applied as a pharmaceutical drug delivery device.     

Study of the Structure and Properties of High-Chromium Cast Irons and Stainless Steels for Chemical Production Pumps

Metal Science and Heat Treatment - The structures and phase compositions of highly-alloyed corrosion-resistant cast irons ChKh22 and ChKh20M, and also stainless steels 10Kh24N19G2M (austenitic) and...     

Forms of wear of contact surfaces in high-temperature lead and lead-bismuth coolants

The results of experimental studies of wear of contact steel and cast-iron surfaces of construction materials in high-temperature (400–550°C) liquid-metal coolants of advanced nuclear power facilities of the BREST and SVBR type are presented. It is shown that long-term serviceability of the surface materials under the working conditions of reactors loops can be assured by forming and maintaining protective oxide coatings on them.     

Video-assisted thoracic surgical procedures: the Mayo experience

In neurodegenerative disorders, hyperphosphorylated tau proteins aggregate into abnormal filaments. In the present study, tau protein alterations were studied in one corticobasal degeneration and seven Pick's disease cases using specific immunological probes. The typical lesions of corticobasal degeneration and Pick's disease were revealed by immunohistochemistry, including the presence of Pick bodies and achromatic swollen neurons, neuritic alterations, and neurofibrillary tangles. Tau-immunoreactive glial tangles were also observed. By immunoblotting, the case of corticobasal degeneration was characterized by the tau profile previously reported to occur in progressive supranuclear palsy with an intense labeling of the two tau 64 and 69 bands, while tau 55 was not visualized. In Pick's disease cases with Pick bodies and neurofibrillary tangles, a tau triplet similar to that encountered in Alzheimer's disease (tau 55, 64 and 69) was detected. Furthermore, a particular tau profile was found in four Pick's disease cases showing only Pick bodies and no neurofibrillary tangles. In these cases, tau 55 and 64 were strongly immunoreactive, whereas tau 69 was almost unlabeled. These differences are likely to be related to particular pools of tau isoforms present within the degenerating neurons. Since there is a great diversity of neurodegenerative disorders with substantial clinical and neuropathological overlap, the electrophoretic profile of tau proteins could represent a useful marker for the type of neurodegeneration.