Ultrastructural characteristics of the cerebral capillaries of aging animals subjected to hypoxic hypoxia

The ultrastructure of capillary walls of the mamillary bodies was studied in rats distributed in two age groups: adult (6-8-month-old) and old (28-30-month-old) animals under hypoxic hypoxia. It was found that age-related differences in the response of brain capillary walls to the injuring agent were reduced to a rapid increase in dystrophic phenomena and less conspicuous compensatory processes seen in the old animals. More profound injuries to other brain tissues adjacent to the vessels were also indicative of less efficacy of the adaptive reactions in the old animals.     

Dynamics of morphofunctional state of the epiphysis after craniocerebral trauma in humans

Histological examination of the epiphyses of 12 persons who perished because of craniocerebral trauma (CCT) showed that even in the first hours after CCT clear manifestations of considerable morphofunctional transformation of epiphyseal cellular elements towards intensification of indoleamine production become obvious. In the cases of death on the 11th–12th post-traumatic day, we observed complete morphofunctional exhaustion of the epiphysis: the cell elements with typical features of pinealocytes practically disappeared.     

Physical and neurological state of the newborn after perinatal asphyxia

Asphyxia neonatorum is the most prevalent birth trauma. Usually it leads to the birth of weak and nonvigorous child. Perinatal asphyxia is the reason of not only postasphyxic hypoxic-ischemic encephalopathy, but also multiple organ dysfunctions. Neurological sequelae and consequences of multisystem dysfunction affect on newborn status in first life months and later on by the muscle tone disturbances, physical and mental retardations. In this paper it is presented modern conceptions about asphyxia origin, risk factors, neurological and systemic complications for child nervous system and organism.     

The morphofunctional characteristics of the cecum in experimental escherichiosis]

Using the model of experimental escherichiosis in mice by means of morphological, immunomorphological, morphometrical and electron microscopy methods, the authors give morphofunctional characteristics of caecum 15 minutes to 2 weeks after inoculation. The authors show the dynamics of infectious process, characterized by changes of microcirculation, increasing lymphoplasmocellular infiltration, dystrophic changes in cells of neuroplexes and degranulation of mast and endocrine cells. The data obtained show that pathological process in caecum during experimental escherichiosis has an immune character, that the above portion of the intestine is a part of endocrine system.     

The morphofunctional characteristics of the cecum in experimental influenza]

On the model of experimental influenza using morphological, immunomorphological, cytochemical, electron microscopy and morphometric methods, the authors provided morphofunctional characteristics of the caecum, showed the progression of infectious process and confirmed the dissemination of the virus, availability of virus particles in different cell populations, among them in lymphoid cells.     

Therapeutic strategies to protect the immature newborn myocardium during resuscitation following asphyxia

Perinatal asphyxia contributes to over one million newborn deaths worldwide annually, and may progress to multiorgan failure. Cardiac dysfunction, of varying severity, is seen in 50%-70% of asphyxiated newborns. Resuscitation is necessary to restore oxygenation to deprived tissues, including the heart. However, reoxygenation of asphyxiated newborns may lead to generation of reactive oxygen species (ROS) and further myocardial damage, termed reperfusion injury. The newborn heart is especially vulnerable to oxidative stress and reperfusion injury due to immature antioxidant defense mechanisms and increased vulnerability to apoptosis. Currently, newborn myocardial protective strategies are aimed at reducing the generation of ROS through controlled reoxygenation, boosting antioxidant defenses, and attenuating cellular injury via mitochondrial stabilization.     

Gender dimorphism in aspartame-induced impairment of spatial cognition and insulin sensitivity

Previous studies have linked aspartame consumption to impaired retention of learned behavior in rodents. Prenatal exposure to aspartame has also been shown to impair odor-associative learning in guinea pigs; and recently, aspartame-fed hyperlipidemic zebrafish exhibited weight gain, hyperglycemia and acute swimming defects. We therefore investigated the effects of chronic lifetime exposure to aspartame, commencing in utero, on changes in blood glucose parameters, spatial learning and memory in C57BL/6J mice. Morris Water Maze (MWM) testing was used to assess learning and memory, and a random-fed insulin tolerance test was performed to assess glucose homeostasis. Pearson correlation analysis was used to investigate the associations between body characteristics and MWM performance outcome variables. At 17 weeks of age, male aspartame-fed mice exhibited weight gain, elevated fasting glucose levels and decreased insulin sensitivity compared to controls (P<0.05). Females were less affected, but had significantly raised fasting glucose levels. During spatial learning trials in the MWM (acquisition training), the escape latencies of male aspartame-fed mice were consistently higher than controls, indicative of learning impairment. Thigmotactic behavior and time spent floating directionless was increased in aspartame mice, who also spent less time searching in the target quadrant of the maze (P<0.05). Spatial learning of female aspartame-fed mice was not significantly different from controls. Reference memory during a probe test was affected in both genders, with the aspartame-fed mice spending significantly less time searching for the former location of the platform. Interestingly, the extent of visceral fat deposition correlated positively with non-spatial search strategies such as floating and thigmotaxis, and negatively with time spent in the target quadrant and swimming across the location of the escape platform. These data suggest that lifetime exposure to aspartame, commencing in utero, may affect spatial cognition and glucose homeostasis in C57BL/6J mice, particularly in males.     

Auditory characteristics and sexual dimorphism in the gypsy moth

ABSTRACT. The auditory characteristics of two populations (laboratory reared and wild) of North American gypsy moths (Lymantriidae: Lymantria dispar L.) were sampled and the neurally derived thresholds of wild males and females to frequencies from 5 to 150 kHz compared. The noctuoid auditory receptors, Al and A2-cell, and putative proprioceptor, B-cell, were identified. Both sexes possess neurally responsive ears but females exhibit median best frequencies significantly lower than those of males. Audiogram comparisons reveal significantly different thresholds at 5–15 kHz, 30–120 kHz and 130–140 kHz, with females less sensitive to all but the lowest frequencies. Wild male populations reveal less audiogram variability than laboratory-reared individuals, while females' tuning curves appear more similar. The high variability present in colony moths warrants caution in the use of laboratory-reared insects for studies that assume natural levels of selection pressure. We suggest that male L. dispar possess adaptively functional ears tuned to the frequencies in the echo-location signals of bats but that the flightless females of this species are not exposed to bat predation and therefore possess ears in a state of evolutionary degeneration.     

Early hypoxic contracture of the myocardium in adult and newborn rats]

The effect of 30 min substrate free hypoxia (H) on isometric tension was studied in isolated myocardium (M) of adult (A) and newborn (N) rats. The perfusion with 50% Na+ H solution caused in AM the development of H contracture which was more than 50% higher than control contracture. H perfusion with 0.1 mM Ca2+, 1.0 mM La3+, and 10.0 mM of caffeine provides the discrimination of control and hypoNa+ contractures. It is assumed that early H contracture in AM is a result of inability of Ca-sequestering system to accumulate intracellular Ca2+ and Ca2+ influxing through the sarcolemma. In myocardium of N rats Na-Ca exchange is proposed as a main source of Ca2+ for H contracture development.     

Variations in sexual dimorphism in the skulls of rats subjected to malnutrition, castration, and treatment with gonadal hormones

Two groups of weanling rats were subjected to malnutrition, one with periodic injections of testosterone (males) and the other with estradiol (females). Two other groups (castrated males or castrated females) received normal feedings. In control animals, the relative weights (mg/gm body weight) of testes, seminal vesicles, and ovaries were greater than in malnourished rats. However, relative weights of those organs in hormone-treated, malnourished animals were greater than in those subjected to malnutrition alone and still greater than in controls. Normal sexual cranial dimorphism (SCD) was decreased 16% by male castration, 23% by malnutrition, and 83% by estradiol treatment in malnourished females. On the other hand, normal SCD was increased 20% by female castration and more than 200% by testosterone treatment in malnourished males. All monosexual comparisons corroborated the bisexual range of distances found. Testicular but not ovarian secretions seemed to influence sexual cranial dimorphism. Malnutrition delayed SCD because of a deficiency of testosterone level in stressed males. It is suggested that estradiol in females may counteract sexual cranial development and that its inhibitory effect may be additive to the testosterone deficit evoked by malnutrition.     

Effect of the antihypoxic agent ionol on the morphofunctional state of the air-blood barrier of the lungs in hypoxic anoxia

It is shown that antihypoxic ionol has promoted normalization of the air-blood lung barrier ultrastructure, activation of the surfactant system under acute hypoxic hypoxia effect as well as compensatory redistribution of the thickness of separate barrier layers due to intensified synthesis of phospholipids which are the components of cytoplasmic membranes and pulmonary surfactant.     

Sex dimorphism in digital formulae of children

This paper presents results of a study designed to: 1) test for a sex difference in the relative lengths of the finger bones, including the second-to-fourth digit ratio (2D:4D), using left-hand radiographs taken in young children, 2) test whether sex differences can be explained by sex differences in fetal growth, and 3) test the serial stability of sex differences in relative digit lengths, including 2D:4D. Results are presented from 1,060 subjects of the California Child Health and Development Studies. One serial replication at about 9 years old is available from 271 subjects. Results indicate that relative digit lengths are sex-dimorphic in children (Manning et al. [1998] Hum. Reprod. 13:3000-3004, [2004] Early Hum. Dev. 80:161-168). Sex differences in digit length ratios are more pronounced within sibships, where shared family factors are controlled, and are not strongly associated with gross measures of fetal growth, like birth length or weight. Thus, sex differences in the fetal growth of the body are not implicated in sex differences in digital formulae, leaving open the possibility of more direct hormonal and/or genetic causation. However, 2D:4D declined between ages 6-8 in a longitudinal sample, and was a less consistent sex-dimorphic marker than 3D:4D across ethnic groups, suggesting that 3D:4D may be a better marker of perinatal sex differentiation. Prior conflicting findings about 2D:4D may be partly explained by variations in age and ethnicity of populations studied.