Socioeconomic determinants of menarche in rural Polish girls using the decision trees method

The aim of this study was to assess the usefulness of the decision trees method as a research method of multidimensional associations between menarche and socioeconomic variables. The article is based on data collected from the rural area of Choszczno in the West Pomerania district of Poland between 1987 and 2001. Girls were asked about the appearance of first menstruation (a yes/no method). The average menarchal age was estimated by the probit analysis method, using second grade polynomials. The socioeconomic status of the girls' families was determined using five qualitative variables: fathers' and mothers' educational level, source of income, household appliances and the number of children in a family. For classification based on five socioeconomic variables, one of the most effective algorithms CART (Classification and Regression Trees) was used. In 2001 the menarchal age in 66% of examined girls was properly classified, while a higher efficiency of 70% was obtained for girls examined in 1987. The decision trees method enabled the definition of the hierarchy of socioeconomic variables influencing girls' biological development level. The strongest discriminatory power was attributed to the number of children in a family, and the mother's and then father's educational level. Using this method it is possible to detect differences in strength of socioeconomic variables associated with girls' pubescence before 1987 and after 2001 during the transformation of the economic and political systems in Poland. However, the decision trees method is infrequently applied in social sciences and constitutes a novelty; this article proves its usefulness in examining relations between biological processes and a population's living conditions.     

Changes in the composition of the causative agents of wound infection in emergency surgery in the period from 1967 through 1987

The composition of the causative agents of suppurations, isolated from suppurating wounds of patients hospitalized at different departments of the Sklifosovski? Emergency Aid Institute was studied. The proportion of representatives of different microbial families among more than 18,000 strains of the causative agents of wound infection was estimated. Fluctuations in the amount and structure of the agents were analyzed in different clinics over the period of 1967-1987. Under the conditions of emergency aid hospital Staphylococcus aureus proved to be the most frequent causative agent of suppurative inflammatory processes at different departments. At the same time no tendency towards an increase of the etiological role of any microbial family in the development of wound infections was noted. The incidence of different causative agents of suppurations was found to vary at different departments, depending on their specialization and season. The results of observations on the composition of the causative agents of wound infection may be used for the planning and evaluation of antiepidemic measures.     

Genetic processes in rural populations of the Tomsk region (migration characteristics)]

The results of analysis of genetic and demographic structure of two village communities of Tomsk region are presented. Migration processes were shown to play important role in forming genetic structure of populations; less than 20% of inhabitants of the communities under study were born in those populations, where they live at present. These village communities are characterized by high values of gametic contribution of the populations situated outside Tomsk region, by intervillage heterogeneity of gene flow structure and by insignificant gametic exchange between the populations. The portions of heterolocal and international marriages offsprings increased from elder to younger groups of inhabitants.     

Synthesis and biological activity of adipokinetic hormone analogues with modifications in the 4-8 region

Several structural characteristics in the molecule of the locust adipokinetic hormone, AKH-I, have been investigated in terms of their importance in determining biologic activity. All modifications tested in this study resulted in analogues with decreased potency in comparison with the parent molecule. However, all analogues that were found to be active gave a full response, although often only at very high doses of peptide. This study has highlighted for the locust receptor(s) the vital role of the side chain of Thr(5), and the importance of positions 4 and 8. For example, when Trp(8) and Phe(4) were exchanged, the resulting analogue (Trp(4),Phe(8)-AKH-I) was one of the least active analogues tested in this study. Although Trp is tolerated quite well as a substitute for Phe(4), with only a 10-fold loss of potency, Phe is not favored as a substitute for Trp(8) (>300 times decrease in potency). On the other hand, 3-[2-napthyl] alanine (Nal) is a better substitute for Trp(8) (only a 100-fold loss in potency). We conclude that position 4 requires a phenyl ring in the side chain, and position 8 an indole ring.     

Synthesis and biological activity of peptides from interferon alpha A region 125-131

Two peptides, IFN-(125-129) (RITLY-I) and [Arg7]IFN-(125-131) (RITLYLR-II), belonging to the putative immunologically active region of interferon alpha A (IFN) were synthesised by the solid-phase method. Both peptides suppress the delayed-type hypersensitivity reaction in vivo as assayed in mice. The peptide (II) either suppresses (0.01-0.1 mg/kg) or stimulates (approximately 1.0 mg/kg) antibody production in mice in response to sheep red blood cells.     

Changes in the lipid composition of blood serum in girls with different somatotypes after a meal

Changes in the neutral lipid and phospholipid composition of blood serum in response to meals were analyzed in girls with different somatotypes. After meals, a statistically significant decrease in the content of free fatty acids was observed in all subjects, irrespective of the somatotype. Statistically significant increases in the contents of readily oxidized phospholipid fractions were observed in girls of subathletic and athletic somatotypes. These data show the changes in the relationship between variable components of the lipid spectrum of lipoproteins. The main structural constituents of membrane lipoproteins, such as stable phospholipid fractions and free cholesterol, did not change in response to meals in girls of any somatotype. These data demonstrate a stability of membrane lipoprotein complexes in response to this physiological stimulus.     

The Relation of Rapid Changes in Obesity Measures to Lipid Profile - Insights from a Nationwide Metabolic Health Survey in 444 Polish Cities

Objective

The impact of fast changes in obesity indices on other measures of metabolic health is poorly defined in the general population. Using the Polish accession to the European Union as a model of political and social transformation we examined how an expected rapid increase in body mass index (BMI) and waist circumference relates to changes in lipid profile, both at the population and personal level.

Methods

Through primary care centres in 444 Polish cities, two cross-sectional nationwide population-based surveys (LIPIDOGRAM 2004 and LIPIDOGRAM 2006) examined 15,404 and 15,453 adult individuals in 2004 and 2006, respectively. A separate prospective sample of 1,840 individuals recruited in 2004 had a follow-up in 2006 (LIPIDOGRAM PLUS).

Results

Two years after Polish accession to European Union, mean population BMI and waist circumference increased by 0.6% and 0.9%, respectively. This tracked with a 7.6% drop in HDL-cholesterol and a 2.1% increase in triglycerides (all p<0.001) nationwide. The direction and magnitude of the population changes were replicated at the personal level in LIPIDOGRAM PLUS (0.7%, 0.3%, 8.6% and 1.8%, respectively). However, increases in BMI and waist circumference were both only weakly associated with HDL-cholesterol and triglycerides changes prospectively. The relation of BMI to the magnitude of change in both lipid fractions was comparable to that of waist circumference.

Conclusions

Moderate changes in obesity measures tracked with a significant deterioration in measures of pro-atherogenic dyslipidaemia at both personal and population level. These associations were predominantly driven by factors not measureable directly through either BMI or waist circumference.     

Individual characteristics of somatotype and skeletal muscle power in girls in the age period from 7 to 11

Sixteen girls were observed for five years during the age period from 7 to 11. The longitudinal study included the annual assessment of constitutional characteristics according to Shtefko-Ostrovskii and the calculation of endomorphy, mesomorphy, and ectomorphy indices from anthropometric data according to Heath-Carter. The indices of skeletal muscle power (aerobic capacity and power; anaerobic power, and power indexa) were determined in a two-load ergometric test using Muller’s equation. The girls demonstrated a 2.5-time more stable somatotype than boys. The most pronounced changes in their constitutional characteristics were observed between the ages of 8 and 9, i.e., a year earlier than in boys. These changes occurred only within the dolichomorphic and brachymorphic groups without transitions between somatotypes. In girls of all ages, the constitutional characteristics were in good correlation with skeletal muscle power. In general, dolichomorphs were characterized by high aerobic indices: their mean aerobic capacity was as high as 83.1 kJ/kg vs. 4.1 kJ/kg in brachymorphs, who showed preferential development of anaerobic mechanisms.     

Changes in immunoreactivity to anti-cGnRH-I and -II are associated with photostimulated sexual status in male quail

In sexually active males exposed to long-day (LD) photoperiod, perikarya in the olfactory bulb, lobus parolfactorius, n. accumbens, and preoptic region were immunoreactive (ir) to an antiserum against gonadotropin-releasing hormone (anti-cGnRH-I), and a cluster of ir-perikarya was found in the caudal-most septal area. Ir-perikarya in these brain areas of sexually inactive short-day (SD) males were located within more discrete areas than those in LD brain, which were more scattered in appearance. Absolute cell numbers were similar between LD and SD brains. Ir-fibers in LD brains were mostly in the external median eminence, along the lateral ventricle to septum (especially in and about the n. accumbens), in the septal-preoptic area, along the third ventricle, and at the n. commissure palli. There were fewer ir-fibers in SD brain. Many small dark ring-like ir-structures were found in the hyperstriatum, hippocampus, and n. taeniae. Interpreted as being ir-terminals on non-ir perikarya, these were not observed in SD males. cGnRH-II ir-perikarya were observed in only two areas regardless of reproductive status: (1) ventral to the substantia grisea centralis and caudal to the oculomotor complex, and (2) scattered in and about the lateral hypothalamus. Ir-fibers occurred in the habenular area, hyperstriatum, hippocampus, parahippocampal area, cortex piriformis, and n. taeniae. cGnRH-II ir-fibers occurred in the external median eminence but were less intensely stained than cGnRH-I ir-fibers. These fibers in SD males were similar except in the diencephalon, where scattered swellings were observed. Thus, the appearance and distribution of anti-cGnRH-I and -II ir-structures change with the sexual status of male quail, but changes in immunoreactivity to anti-cGnRH-I appear to be more widespread.     

Embryonic fibroblasts from Gpx4+/- mice: a novel model for studying the role of membrane peroxidation in biological processes

A previous study using mice null for Gpx4 indicates that PHGPx plays a critical role in antioxidant defense and is essential for the survival of the mouse. In the present study, we further analyzed the stress response of MEFs (murine embryonic fibroblasts) derived from mice heterozygous for the Gpx4 gene (Gpx4(+/-) mice). MEFs from Gpx4(+/-) mice have a 50% reduction in PHGPx expression without any changes in the activities of other major antioxidant defense enzymes. Compared to MEFs from Gpx4(+/+) mice, MEFs from Gpx4(+/-) mice were more sensitive to exposure to the oxidizing agent t-butyl hydroperoxide (t-BuOOH), and t-BuOOH exposure induced increased apoptosis in MEFs from Gpx4(+/-) mice. When cultured at low cell density, MEFs from Gpx4(+/-) mice also showed retarded growth under normal culture conditions (20% oxygen) that was reversed by culturing under low oxygen (2% oxygen). In addition, oxidative damage was increased in the MEFs from the Gpx4(+/-) mice, as indicated by increased levels of F(2)-isoprostanes and 8-oxo-2-deoxyguanosine in these cells. Our data demonstrate that MEFs from Gpx4(+/-) mice are more sensitive to oxidative stress because of reduced expression of PHGPx.