Sertoli cell types in the Sertoli-cell-only syndrome: relationships between Sertoli cell morphology and aetiology

Histological study of testicular biopsies from infertile men showing Sertoli-cell-only tubules due to hypogonadotropic hypogonadism, cryptorchidism, oestrogen treatment, chemotherapy or Del Castillo's syndrome, revealed four types of Sertoli cells: (1) normal adult mature cells showing an indented nucleus, grossly triangular in shape with a prominent tripartite nucleolus; (2) immature cells with round regularly outlined nuclei and immature cytoplasm; (3) dysgenetic cells showing immature nuclei and a nearly mature cytoplasm with less developed cytoplasmic organelles; and (4) involuting cells with very irregularly outlined nuclei and a mature cytoplasm containing abundant lipid droplets and residual bodies and atypical inter-Sertoli junctional specializations. Testes from men with hypogonadotropic hypogonadism showed only immature Sertoli cells; cryptorchid testes showed dysgenetic cells and occasional normal cells; and after treatment with oestrogens or chemotherapy the testes showed involuting cells and normal cells. The testes of men with Del Castillo's syndrome could be classified into three groups, according to the Sertoli cell type present: mature, dysgenetic and involuting cells. This finding suggests that Del Castillo's syndrome may be due to at least three different aetiologies.     

Literacy not intelligence moderates the relationships between economic development,income inequality and health

Objectives. Kanazawa (2006) presented data allegedly supporting a racist version of evolutionary psychology that claims that the populations of wealthier and more egalitarian societies live longer and stay healthier, not because they are wealthier and more egalitarian, but because they are more intelligent. The objectives of this study are: (i) to determine the relationship between IQ and literacy in Kanazawa's sample of countries and (ii) to reanalyse Kanazawa's dataset using measures of literacy in lieu of national IQ test scores. Method. Correlation and regression were employed. Results. National literacy scores across the countries in the sample are highly skewed. In spite of this, the literacy measures are highly correlated with alleged differences in national IQ (r = .83–.86). The measure of literacy together with economic development (GDPpc) and income inequality (Gini coefficient) control at least 59–64% of the variance in national life expectancy at birth. Conclusion. There is no scientific justification for believing that alleged intelligence differences play any role in explaining international differences in health status. Measures of alleged national IQ scores are highly confounded with differences in literacy. Literacy is a key factor in the health of any community and policies designed to enhance the literacy of a population are expected to lead to significant improvements in health status.     

Kinematic variability and relationships characterizing the development of walking

The purposes of this study were: (1) to determine the pattern of variability and relationships in joint kinematics characterizing the development of walking and (2) to determine whether controlling for postural stability in new walkers results in less variability. The variability and relationships among hip, knee, and ankle motions were measured during 10 gait cycles of new walkers, supported new walkers, two-year-olds and seven-year-olds. Fourier series were generated for each joint motion and standard deviations were compared across groups. An age-related decline in variability was evident in select portions of the cycle. Stance and swing phase duration correlated with cycle duration for all ages. Postural support did not lessen variability in joint rotations for new walkers. Cross-correlations for hip-knee, knee-ankle, and hip-knee rotations were strong across all groups. These results suggest that a coordinative structure for walking produces strong intralimb coupling early in development, despite variability in select portions of joint motions.     

Neutralization of the adenoviruses types 1 to 28: Specificity and antigenic relationships

Summary Cross-neutralization tests of rabbit immune sera against adenoviruses types 1 through 28 revealed a high degree of specificity in many instances. Reciprocal cross-reactions were observed between types 4 and 16, types 15 and 25, types 3 and 7, types 7, 11, and 14, types 11 and 21 and, with some exceptions, between types 1, 2, 5, 6, and 12. The majority of the cross-neutralizations were of low titer. No antigenic difference was found between type 7 and 7a. The antigenically related subgroups correspond well with subgroups of the human adenoviruses, as defined by other criteria.Aided by grants of the Deutsche Forschungsgemeinschaft.     

Corticohypothalamic relationships during the development and realization of the conditioned reflex

The influence of motivational, emotiogenically positive and emotiogenically negative structures of the hypothalamus on the development and realization of conditioned reflexes was investigated in the experiments on dogs, cats, and rats. It was shown that the motivational structures primarily increase excitability of cortical neurons during the development of the conditioned connection, while the emotiogenically negative and emotiogenically positive structures increase the efficiency of synapses. A high degree of correlatedness of the averaged evoked responses to the conditional stimulus in the hypothalamus and new cortex is characteristic for the consolidated conditioned reflex. Direct stimulation of the motivational-alimentary zones of the hypothalamus reproduce food-procuring conditioned reflexes in dogs, while stimulations of the emotiogenically negative zones reproduce defense conditioned reflexes. Stimulation of the emotiogenically positive zones does not reproduce either; however, an intensification of the activity of neurons of the hypothalamus was recorded in rats during the successful accomplishment of the conditioned reaction of avoidance of an aversive stimulus. In cats which are capable of restraining a conditioned motoric reaction for the sake of obtaining a preferred food, the “motivational”, long-latency functional connections between neurons of the lateral hypothalamus and the prefrontal cortex predominate. Short-latency “informational” connections predominate in the “impulsive” cats. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 43, No. 2, pp. 12–21, March–April, 1993.     

Changes in the histone/DNA ratio during the development of a multicellular organism

Changes in the histone/DNA ratio are studied in the star-fish. It is found that the development of a multicellular organism is based on the principle of nonequivalence of the sister cells which is described by the distribution of Polya. It is postulated that the development of an organism obeys the laws of mathematics. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 12, pp. 695–698, December, 1996     

硫化氢与机体损伤后线粒体变化关系的研究现状

线粒体作为细胞内氧化代谢的主要场所、供应细胞主要能量的细胞器,在细胞正常生理功能的维持上起重要作用,对各种各样的损伤极为敏感。国内外研究证明,外源性硫化氢在机体损伤的情况下对神经细胞、平滑肌细胞、心肌细胞、表皮细胞等细胞内的线粒体有一定的保护作用,减轻细胞的损伤程度,从而促进机体恢复。本文着重总结硫化氢与几种重要器官损伤后细胞内线粒体的具体变化机制的关系,对硫化氢减轻线粒体损伤的最新研究进展进行综述。     

Evolution and development of a multicellular organism: scalability, resilience, and neutral complexification

To increase the evolvability of larger search spaces, several indirect encoding strategies have been proposed. Among these, multicellular developmental systems are believed to offer great potential for the evolution of general, scalable, and self-repairing organisms. We reinforce this view, presenting the results achieved by such a model and comparing it against direct encoding. Extra effort has been made to make this comparison both general and meaningful. Embryonal stages, a generic method showing increased evolvability and applicable to any developmental model, are introduced. Development with embryonal stages implements what we refer to as direct neutral complexification: direct genotype complexification by neutral duplication of expressed genes. The results show that, even for high-complexity evolutionary targets, the developmental model proves more scalable. The model also shows emergent self-repair, which is used to produce highly resilient organisms.     

General approach to the development of artificial blood-circulating equipment

All-Russian Scientific-Research Institute for Medical Instrument Engineering, Russian Academy of Medical Sciences, Moscow. Manufacturing Association Korpus, Saratov. Translated from Meditsinskaya Tekhnika, No. 3, pp. 10–12, May–June, 1994.     

Adequate function of the cell: Interactions between the needs of the cell and the needs of the organism

The continuous maintenance of cell adequate function (cellular stress) is considered to be the main feature which characterizes the activity of a live cell. In accordance with the concept of cellular stress, the transition of the cell to the state of adequate funcitoning represents a dual commitment. The cell must function adequately to respond to the demands of the organism and to provide for its own needs. Thus, it is proposed that two systems exist for the regulation of the adequate function of the cell: one enabling the cell to respond to the demands of the organism, and the other providing for the needs of the cell itself. The hormonal system of the organism represents the first of these mechanisms, and I believe that another system exists for regulation of intracellular needs. Adequate function of the cell is determined by the regulative, controlling and defense mechanisms. The balance between the needs of the cell and of the organism should be a concern of physician, since it provides for the optimal function and health of the organism as a whole.