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Neurodegenerative diseases are among the main causes of death in the United States, leading to irreversible disintegration of neurons. Despite intense international research efforts, cellular mechanisms that initiate neurodegeneration remain elusive, thus inhibiting the development of effective preventative and early onset medical treatment. To identify underlying cellular mechanisms that initiate neuron degeneration, it is critical to identify histological and cellular hallmarks that can be linked to underlying biochemical processes. Due to the poor tissue preservation of degenerating mammalian brain tissue, our knowledge regarding histopathological hallmarks of early to late degenerative stages is only fragmentary. Here, we introduce a novel model organism to study histological hallmarks of neurodegeneration, the spider Cupiennius salei. We utilized toluidine blue-stained 0.9-μm serial semithin and 50-nm ultrathin sections of young and old spider nervous tissue. Our findings suggest that the initial stages of neurodegeneration in spiders may be triggered by (1) dissociation of neuron- and glia-derived microtubules, and (2) the weakening of microtubule-associated desmosomal junctions that lead to the unraveling of neuron-insulating macroglia, compromising the structural integrity of affected neurons. The involvement of macroglia in the disposal of neuronal debris described here-although different in the proposed transport mechanisms-shows resemblance to the mammalian glymphatic system. We propose that this model system is highly suitable to investigate invertebrate neurodegenerative processes from early onset to scar formation and that this knowledge may be useful for the study of neurodegeneration in mammalian tissue., (© 2023 Wiley Periodicals LLC.)

Rosa damascena, or Damask rose, is a rose hybrid commonly harvested for rose oil used in perfumery and for rose water used to flavor food. The petal extract of R. damascena was recently found to decrease Drosophila melanogaster mortality without impairing reproductive fitness or metabolic rate. Here, we report that R. damascena extended both mean and maximum lifespan of the fly. The extract also protected against oxidative stress in flies, predominantly in females. However, it did not alter mitochondrial respiration or content, superoxide production, or the major antioxidant defenses, superoxide dismutase and catalase. The extract increased survival in both sexes when exposed to reduced iron, though surprisingly, it sensitized both sexes to heat stress (survival at 37°C), and appeared to down-regulate the major heat shock protein HSP70 and the small mitochondrial heat shock protein HSP22, at 25°C and after heat shock (4 h at 37°C). We hypothesize that R. damascena extends lifespan by protecting against iron, which concomitantly leads to decreased HSP expression and compromising heat tolerance.

Objective: To test the accuracy of a birth weight prediction equation based on maternal characteristics in Hispanic women., Study Design: A previously published birth weight prediction equation based on maternal and pregnancy-specific characteristics was used to predict birth weights for 283 normal Caucasian women of Hispanic ethnicity. The accuracy of these birth weight estimates was compared to a similarly selected group of 233 non-Hispanic Caucasian gravidas who were located 2500 miles away., Results: Birth weight predictions for Hispanic women were accurate to within +/- 8.4% (+/- 287 g). The percentages of birth weights predicted to within +/- 15 and +/- 10% of actual values were 84 and 68%, respectively. These results were no different than those that were obtained for non-Hispanic Caucasian gravidas., Conclusions: A previously derived birth weight prediction equation based on maternal and pregnancy-specific characteristics alone successfully predicts term birth weight in normal Hispanic gravidas to within +/- 8.4% (+/- 287 g).

Objective: To investigate the accuracy of ultrasonic fetal biometric algorithms for estimating term fetal weight., Study Design: Ultrasonographic fetal biometric assessments were made in 74 Hispanic women who delivered at 37-42 weeks of gestation. Measurements were taken of the fetal biparietal diameter, head circumference, abdominal circumference and femur length. Twenty-seven standard fetal biometric algorithms were assessed for their accuracy in predicting fetal weight. Results were compared to those obtained by merely guessing the mean term birth weight in each case., Results: The correlation between ultrasonically predicted and actual birth weights ranged from 0.52 to 0.79. The different ultrasonic algorithms estimated fetal weight to within +/- 8.6-15.0% (+/- 295-520 g) of actual birth weight as compared with +/- 13.6% (+/- 449 g) for guessing the mean birth weight in each case (mean +/- SD). The mean absolute prediction errors for 17 of the ultrasonic equations (63%) were superior to those obtained by guessing the mean birth weight by 3.2-5.0% (96-154 g) (P < .05). Fourteen algorithms (52%) were more accurate for predicting fetal weight to within +/- 15%, and 20 algorithms (74%) were more accurate for predicting fetal weight to within +/- 10% of actual birth weight than simply guessing the mean birth weight (P < .05). Ten ultrasonic equations (37%) showed significant utility for predicting fetal weight > 4,000 g (likelihood ratio > 5.0)., Conclusion: Term fetal weight predictions using the majority of sonographic fetal biometric equations are more accurate, by up to 154 g and 5%, than simply guessing the population-specific mean birth weight.

Study Objective: To examine factors that motivate people to become and remain basic life support (BLS) and advanced cardiac life support (ACLS) instructors., Design: A questionnaire was mailed to 967 BLS and ACLS instructors., Setting: The study was performed in the San Francisco Bay Area., Type of Participants: All BLS and ACLS instructors whose names were registered with the Santa Clara County Affiliate of the American Heart Association., Results: Although there is room for improvement, 81% of the instructors were satisfied with their jobs. "Satisfaction in performing a valuable service" was the predominant reason they became instructors. "Lack of time" was the main factor causing people to stop teaching., Conclusion: The majority of BLS and ACLS instructors surveyed were quite happy. The current system appears to be working in that the teachers themselves are satisfied. An accurate portrait of BLS and ACLS instructors is crucial for organizations such as the American Heart Association if they wish to attract and retain instructors.

The fight against tuberculosis in Vietnam is based on bacteriological case-finding since 1956. First pilot-studies with this method showed among the population of towns a very high incidence of smear-positive cases of about 2.5%. The systematic fight was interrupted by the war from 1964 to 1975. Nevertheless from an analysis of the TB-situation made in 1976 resulted a percentage of 0.14-0.37 in comparable groups of population. The relatively high number of smear-positive cases has decreased in 1980 to 0.03%. The actual program of the fight against TB and the targets of its different periods are described.