A new method for estimating voice sounds transmitted to the chest wall in children and adolescents

A new method for estimating voice sound transmission to the chest wall is proposed. The spectral characteristics of voice-transmitted sounds have been estimated in children and adolescents. A total of 37 subjects aged 7–17 yers were examined. The frequency of the first spectral peak of the voice-transmitted sounds “tree, tree” (M ± SD) is 263.7 ± 7.82 and 253 ± 4.29 Hz at ages of 7–11 and 12–14 years, respectively. In male adolescents aged 15–17 years, this frequency is decreased to 100–150 Hz. The slope of the descending segment of the spectrum on the high-frequency side of the peak steadily increases on moving from the upper to the lower zones of the lungs, which may be related to the increase in the air content of the lung tissue. The difference between the amplitudes of the first and second spectral peaks of voice-transmitted sounds over symmetric regions of the chest on the right and left sides (Me(Q75-Q25)) is ?0.1(11.0) dB and does not depend on age or sex, which can be interpreted as an average statistical symmetry of sound transmission.     

Hormonally regulated programmed cell death in barley aleurone cells

Cell death was studied in barley (cv Himalaya) aleurone cells treated with abscisic acid and gibberellin. Aleurone protoplasts incubated in abscisic acid remained viable in culture for at least 3 weeks, but exposure to gibberellin initiated a series of events that resulted in death. Between 4 and 8 days after incubation in gibberellin, >70% of all protoplasts died. Death, which occurred after cells became highly vacuolated, was manifest by an abrupt loss of plasma membrane integrity followed by rapid shrinkage of the cell corpse. Hydrolysis of DNA began before death and occurred as protoplasts ceased production of alpha-amylase. DNA degradation did not result in the accumulation of discrete low molecular weight fragments. DNA degradation and cell death were prevented by LY83583, an inhibitor of gibberellin signaling in barley aleurone. We conclude that cell death in aleurone cells is hormonally regulated and is the final step of a developmental program that promotes successful seedling establishment.     

Copper-induced liver fibrosis affects the behavior of bone marrow cells in primary culture

Background

The present study investigated the effects of low-molecular-weight components of bovine colostrum (LMCC), which were administered per os, on the differentiation, growth, and survival of cells obtained from the bone marrow of rats in primary culture.

Methods

Bone marrow cells (BMCs) were obtained from both the rat femurs and were cultured in medium 199 supplemented with antibiotics (8% streptomycin and 8% gentamycin) and 20% inactivated fetal calf serum. In addition, the number of BMCs was counted and their morphotypes were determined.

Results

Animals were treated with copper (Cu) sulfate to induce liver fibrosis. Subsequent treatment with LMCC eliminated growth inhibition and normalized the bodyweight and temperature of animals with Cu-induced liver fibrosis. The number of lymphocytes in the bone marrow of animals with Cu-induced liver fibrosis was significantly higher than that in the bone marrow of control animals. The number of neutrophils in untreated animals with liver fibrosis and LMCC-treated animals with liver fibrosis was lower than that in control animals. Neutrophils obtained from untreated animals with liver fibrosis and LMCC-treated animals with liver fibrosis underwent two-times faster degradation in vitro than neutrophils obtained from control animals.

Conclusions

Our results indicate that LMCC affects the distribution of different morphological types of BMCs but does not prevent their degradation in vitro, which was two-times faster than that of BMCs obtained from control animals.

     

Analysis of <Emphasis Type="Italic">GJB6</Emphasis> (Сx30) and <Emphasis Type="Italic">GJB3</Emphasis> (Сx31) genes in deaf patients with monoallelic mutations in <Emphasis Type="Italic">GJB2</Emphasis> (Сx26) gene in the Sakha Republic (Yakutia)

Тhe DNA testing of autosomal recessive deafness type 1A (DFNB1A, MIM 220290) is complicated when deaf patients have only monoallelic (heterozygous) recessive mutations in the GJB2 (Сх26) gene that is uninformative for establishment of diagnosis. Such patients may be “random” heterozygous carriers of GJB2 mutations as well as have the mutant allele in a cis-regulatory region of GJB2 gene, in element genes encoding other connexins: GJB6 (Сх30) or GJB3 (Сх31). Previous studies of genetic causes of hearing loss in patients from Yakutia were directed to search for only mutations in the GJB2 gene, and the DNA diagnostics was uninformative for 9.7% (38/393) of the patients with monoallelic GJB2 mutations. In this work the search for mutations in genes GJB3 and GJB6 and two deletions с.del(GJB6-D13S1830) and с.del(GJB6-D13S1854) to the cis-regulatory region of GJB2 gene was conducted in 35 patients with GJB2 monoallelic mutations and in 104 normal hearing individuals. The genes studied are two synonymous substitution c.489G>A (р.Leu163Leu) (GJB6) and c.357C>T (р.Asn119Asn) (GJB3) have been found, probably do not have clinical significance, and two nonsynonymous substitution c.301G>A (p.Glu101Lys) (GJB6) and с.580G>A (p.Ala194Thr) (GJB3). Additional experimental evidences are needed for confirmation of pathogenic significance of detected nonsynonymous substitutions in development of hearing loss in studied patients. Diagnosis of the DFNB1A was confirmed in only one patient, who was discovered by the deletion с.del(GJB6-D13S1830) (GJB2) in combination with a recessive mutation с.35delG (GJB2). In general, our results indicate low contribution of mutations in genes GJB6 and GJB3 in hearing loss etiology in Yakutia.     

Stress early in life leads to cognitive impairments,reduced numbers of CA3 neurons and altered maternal behavior in adult female mice

The hippocampus is a crucial part of the limbic system involved both in cognitive processing and in the regulation of responses to stress. Adverse experiences early in life can disrupt hippocampal development and lead to impairment of the hypothalamic‐pituitary‐adrenal axis response to subsequent stressors. In our study, two types of early‐life stress were used: prolonged separation of pups from their mothers (for 3 hours/day, maternal separation, MS) and brief separation (for 15 minutes/day, handling, HD). In the first part of our study, we found that adult female mice (F0) who had experienced MS showed reduced locomotor activity and impairment of long‐term spatial and recognition memory. Analysis of various hippocampal regions showed that MS reduced the number of mature neurons in CA3 of females, which is perhaps a crucial hippocampal region for learning and memory; however, neurogenesis remained unchanged. In the second part, we measured maternal care in female mice with a history of early‐life stress (F0) as well as the behavior of their adult offspring (F1). Our results indicated that MS reduced the level of maternal care in adult females (F0) toward their own progeny and caused sex‐specific changes in the social behavior of adult offspring (F1). In contrast to MS, HD had no influence on female behavior or hippocampal plasticity. Overall, our results suggest that prolonged MS early in life affects the adult behavior of F0 female mice and hippocampal neuronal plasticity, whereas the mothers' previous experience has effects on the behavior of their F1 offspring through disturbances of mother‐infant interactions.     

The retinal conformation and its environment in rhodopsin in light of a new 2.2 A crystal structure

A new high-resolution structure is reported for bovine rhodopsin, the visual pigment in rod photoreceptor cells. Substantial improvement of the resolution limit to 2.2 A has been achieved by new crystallization conditions, which also reduce significantly the probability of merohedral twinning in the crystals. The new structure completely resolves the polypeptide chain and provides further details of the chromophore binding site including the configuration about the C6-C7 single bond of the 11-cis-retinal Schiff base. Based on both an earlier structure and the new improved model of the protein, a theoretical study of the chromophore geometry has been carried out using combined quantum mechanics/force field molecular dynamics. The consistency between the experimental and calculated chromophore structures is found to be significantly improved for the 2.2 A model, including the angle of the negatively twisted 6-s-cis-bond. Importantly, the new crystal structure refinement reveals significant negative pre-twist of the C11-C12 double bond and this is also supported by the theoretical calculation although the latter converges to a smaller value. Bond alternation along the unsaturated chain is significant, but weaker in the calculated structure than the one obtained from the X-ray data. Other differences between the experimental and theoretical structures in the chromophore binding site are discussed with respect to the unique spectral properties and excited state reactivity of the chromophore.     

The hydrochemical response of small and shallow floodplain water bodies to temporary surface water connections with the main river

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Photosynthetic apparatus in primary leaves of barley seedlings grown under blue or red light of very low photon flux densities

Chlorophyll (Chl) a and Chl b contents, rate of CO₂ gas exchange, quenching coefficients of chlorophyll fluorescence, and endogenous phytohormones have been studied in primary leaves of barley seedlings cultivated under blue (BL) or red (RL) light. Photon flux densities (PFD) were between 0.3 and 12 mol m^-2 s^-1. Plants grown at PFD of 0.3 mol m^-2 s^-1 demonstrated in BL tenfold and in RL threefold decreased Chl content compared to plants grown at 12 mol m^-2 s^-1. Chl a/b ratio increased from 2.3–2.5 to 4.4–4.5 in BL, not in RL, following the decrease in PFD at plant cultivation from 12 to 0.3 mol m^-2 s^-1. Plants cultivated at weak BL demonstrated severalfold decreased rate of photosynthetic CO₂ uptake, whereas decrease in PFD of RL from 12 to 0.3 mol m^-2 s^-1 caused only 20% de cline in the rate of photosynthesis. Decrease in PFD during a plant cultivation reduced the maximum quantum yield of photosynthesis in BL, not in RL leaves. Light response curves of non-photochemical and photochemical quenching of chlorophyll fluorescence calculated on the basis of absorbed quanta were not affected by PFD of RL during plant cultivation. On the contrary, both non-photochemical quenching and accumulation of Q_A ^-, reduced primary acceptor of Photosystem II, occurred at lower amounts of absorbed quanta in leaves of BL plants grown at 0.3 than at 12 mol m^-2 s^-1. Two photoregulatory reactions were suggested to exert the light control of the development of photosynthetic apparatus in the range of low PFDs. The photoregulatory reaction saturating by very low PFDs of RL was supposed to be mediated by phytochrome. Phytochrome was proposed to enhance (as related to other pigment-protein complexes of thylakoids) the accu mulation of chlorophyll- b-binding light-harvesting complex of Photosystem II (LHC II). It acts independently of the pigment mediating the second photoregulatory reaction, as evidenced by the results of experiments with plant growth under mixed blue plus red light. The contents of cytokinins and indole-3-acetic acid in a leaf were not significantly affected by either light quality and PFD thus indicating those phytohormones not to be involved into photoregulatory processes.     

New methods of X-ray surgical diagnosis and treatment of varicocele in children and adolescents

The authors studied 520 patients with left-sided varicocele by left-sided phleborenotesticulography of Doppler ultrasonography, tensiometry of the left renotesticular venous system, blood gas composition, hormonal parameters, and etc. They present rationale for and evidence illustrations of aortomesenteric compression of the left renal vein, left-sided phleborenal hypertension prior to and after surgery for endovascular occlusion of the left testicular vein, before and following intervenous proximal testiculoiliac venous bypass surgery. The data of andrological dysfunction in patients with varicosis of the pampiniform plexus and spermatic cord (varicocele) are presented. An algorithm of examination and treatment of this cohort of patients, by using both miniinvasive techniques (for X-ray endovascular occlusion of the temporal veins under local anesthesia) and high tech operations using microsurgical techniques (testiculoiliac venous anastomosis), is outlined.     

Detection of Hispidin by a Luminescent System from Basidiomycete <Emphasis Type="Italic">Armillaria borealis</Emphasis>

In in vitro experiments, the possibility of using a luminescent system extracted from the luminous fungus Armillaria borealis has been shown to detect and determine the concentration of hispidin. A linear dependence of the luminescent response on the content of hispidin in solutions in the concentration range of 5.4 × 10^–5–1.4 × 10^–2 µM was detected. The stability of the enzyme system and the high sensitivity of the bioluminescent reaction allows carrying out multiple measurements with the analyte detection limit of 1.3 × 10^–11 g. The obtained results show the prospects of creating a rapid bioluminescent method for the analysis of medical substances or extracts from various biological objects for the presence of hispidin.