[Effects of chronic caloric restriction on the age-associated peculiarities of explorative behaviour in rats].

Long-term caloric restriction (CR) has been reported to extend the life spans, delay the onset and decrease the incidence of a broad spectrum of age-associated diseases. However, its effect on rat explorative behaviour is still unclear. In the present study, a number of behavioural measures were continuously monitored in 3-, 12-, 24-25-, 28-29- and 35-44-month-old male Wistar rats that were fed either ad libitum or placed on a caloric restricted diet. A gradual decline in locomotor activity of the ad libitum fed rats has been determined during aging in the open field test. In the CR groups, 3-month-old rats exhibited lower levels of exploratory behavior, compared to rats on the control diet. 24-25-month-old CR rats exhibited higher levels of exploratory behaviour, compared to ad libitum fed animals of the same age. Chronic dietary restriction nullified the age-dependent decline in locomotor activity and explorative behaviour of rats.

Wnt1 and BMP2: two factors recruiting multipotent neural crest progenitors isolated from adult bone marrow.

Recent studies have shown that neural crest-derived progenitor cells can be found in diverse mammalian tissues including tissues that were not previously shown to contain neural crest derivatives, such as bone marrow. The identification of those "new" neural crest-derived progenitor cells opens new strategies for developing autologous cell replacement therapies in regenerative medicine. However, their potential use is still a challenge as only few neural crest-derived progenitor cells were found in those new accessible locations. In this study, we developed a protocol, based on wnt1 and BMP2 effects, to enrich neural crest-derived cells from adult bone marrow. Those two factors are known to maintain and stimulate the proliferation of embryonic neural crest stem cells, however, their effects have never been characterized on neural crest cells isolated from adult tissues. Using multiple strategies from microarray to 2D-DIGE proteomic analyses, we characterized those recruited neural crest-derived cells, defining their identity and their differentiating abilities.

Cerebellar stem cells act as medulloblastoma-initiating cells in a mouse model and a neural stem cell signature characterizes a subset of human medulloblastomas.

Cells with stem cell properties have been isolated from various areas of the postnatal mammalian brain, most recently from the postnatal mouse cerebellum. We show here that inactivation of the tumor suppressor genes Rb and p53 in these endogenous neural stem cells induced deregulated proliferation and resistance to apoptosis in vitro. Moreover, injection of these cells into mice formed medulloblastomas. Medulloblastomas are the most common malignant brain tumors of childhood, and despite recent advances in treatment they are associated with high morbidity and mortality. They are highly heterogeneous tumors characterized by a diverse genetic make-up and expression profile as well as variable prognosis. Here, we describe a novel ontogenetic pathway of medulloblastoma that significantly contributes to understanding their heterogeneity. Experimental medulloblastomas originating from neural stem cells preferentially expressed stem cell markers Nestin, Sox2 and Sox9, which were not expressed in medulloblastomas originating from granule-cell-restricted progenitors. Furthermore, the expression of these markers identified a subset of human medulloblastomas associated with a poorer clinical outcome.

[Criteria for assessment of endogenous intoxication in patients with pelvic peritonitis].

The time course of changes in the serum levels of average mass molecules and malondialdehyde in patients with pelvic peritonitis was studied within two weeks after surgery. The values of the above indices of endogenous intoxication (EI) were found to be 1.3-2.9 times higher than the normal values almost throughout the follow-up (p < 0.05). An integral EI coefficient (EIC) including relative (as compared with the normal values) EI indices was proposed to evaluate the magnitude of EI. In patients with pelvic peritonitis, EIC was established to be 2.9-4.8 times greater than the normal values (p < 0.05) in all follow-up periods. Thus, the application of EIC enhances the sensitivity of EI diagnosis in patients with pelvic peritonitis as compared with that in the determination of individual EI indices.

[Integral estimate of endogenous intoxication and its correction with sodium hypochlorite in inflammatory diseases of small pelvic organs].

The parameters of endogenous intoxication (EI) were studied in patients with inflammatory small pelvic organs diseases complicated by organs pelviperitonitis and generalized peritonitis. The integral index of EI--endogenous intoxication coefficient (EIC) was developed, which included relative values (as to the normal values) of the total and effective concentration of albumin, medium molecular peptides and leukocytic intoxication index. The values multiplied together are EIC. In patients with inflammatory small pelvic organs diseases, the level of EI was shown to considerably increase. The use of EIC was ascertained to significantly increase the accuracy of diagnosis of early-stage EI, to perform detoxifying therapy, and monitor its efficiency, as confirmed by the use of sodium hypochlorite in the combined treatment of patients with inflammatory small pelvic organs diseases.

[Age-dependent effects of flavonoids on secretory function of the rat liver].

The effects of the chamomilla recutita (1) flavonoids (chamiloflan) on bilegenesis of the adult and old white rats were investigated. Chamiloflan (20, 40 and 80 mg/kg) induced a dose-dependent increase in the bile flow and bile acid secretion in rats of both age groups. Cholesterol concentration in the liver and bile cholesterol secretion were not changed in the treated adult rats. Chamiloflan increased cholesterol bile secretion and reduced lipid content in the liver of the old rats.

Three-particle correlations in nonideal dusty plasma.

Results are given of experimental investigation of three-particle correlations for liquid plasma-dust structures formed in the electrode layer of a high-frequency capacitive discharge. The obtained three-particle correlation functions for experimental and numerical data are analyzed and compared with the superposition approximation. The forming of clusters of macroparticles in plasma-dust systems being analyzed is revealed.

Subfamilies and nearest-neighbour dendrogram for the LTRs of human endogenous retroviruses HERV-K mapped on human chromosome 19: physical neighbourhood does not correlate with identity level.

Sequences of 45 long terminal repeats (LTRs) of the human endogenous retroviruses HERV-K family, precisely mapped by us earlier on human chromosome 19, were determined and a nearest-neighbour dendrogram was constructed. No correlation was observed between the degree of identity of the LTR pairs and their relative positions on the chromosome. Thus, sequences of distantly located LTRs, even positioned on different chromosome arms, could be highly similar to each other, whereas those of closely located LTRs could differ significantly. We conclude that the LTRs have randomly transposed across the chromosome in the course of evolution. The alignment of the LTR sequences allowed us to assign most of the LTRs to two major subfamilies. The LTRs belonging to the first subfamily (LTR-I) are characterised by higher intrasubfamily sequence divergence than those of the second subfamily (LTR-II). The two subfamilies are easily distinguished by the presence of characteristic deletions/insertions in the LTR sequences. The higher divergence of the first subfamily members suggests that their propagation started at earlier stages of evolution, probably soon after the insertion of their ancestral sequence into the primate genome. In turn, each of the subfamilies includes several distinct branches with various degrees of intragroup divergence and with characteristic diagnostic features, suggesting that the members of the branches represent amplified copies of particular master genes which had appeared at different periods of evolution. The sequences of the LTRs demonstrate a characteristic distribution of conservative and variable regions, indicating that the LTRs might have some sequence-dependent functions in the primate genome.

[Thymus gland pathology in myasthenia gravis: cause or consequence?]. / Patologiia timusa pri miastenii: prichina ili sledstvie?

Analysis of the literature data and of the findings of histologic and immunohistochemical studies of operation biopsy specimens of the thymus obtained from 92 patients with myasthenia has demonstrated that abnormalities of the thymus are characteristic of myasthenia patients. In nontumor involvement of the thymus (84.7 percent of the examinees) these abnormalities present as thymic parenchyma involution of varying gravity, combined (in 54.3 percent of patients) with hyperplasia of intralobular perivascular cavities, this simulating the so-called thymic hyperplasia with lymphoid follicles. Furthermore, impaired expression of certain epitheliocytic antigens is detectable and changed counts of these cells subpopulations; thymic hormones hyperproduction occurs in young patients. In thymomas (15.3 percent of the examined myasthenia patients) the tumor epithelial cell subcortical and/or cortical antigens are intact, thymic hormones production is not always excessive, and disorders in some antigens expression are similar to those observed in nontumor involvement of the thymus. Thymic dysfunction appears to play the key role in the pathogenesis of autoimmune disturbances in myasthenia, and disordered activity of the epithelial cells and lymphoepithelial interactions may be the major factors here.