Congenital sensorineural hearing loss is related to mutations in numerous genes encoding the structures of the inner ear in majority of the cases. Mutations in GJB2 gene are the most frequently ...identified causes of congenital nonsyndromal hearing loss. GJB2 gene testing became a routine clinical tool. For GJB2-negative patients new genetic approaches including methods based on new generation sequencing give a chance to identify mutations in other genes. The frequent reason of mild-to-moderate hearing loss such as the deletions/mutations of the gene STRC encoding stereocilin protein were recognized (OMIM: 606440).
To evaluate the audiological features in hearing impaired patients with deletions and point mutations in the STRC gene.
The group of 28 patients from 21 unrelated families with pathological mutations in the STRC gene underwent audiological examination. The description and analysis of the results of full audiological examination was provided.
All patients initially had bilateral nonsyndromal sensorineural hearing loss. Among 11 homozygotes of large deletion harboring STRC to CATSPER2 genes were 7 male individuals indicating the presence of male infertility syndrome. In general, 7 children failed audiological screening and 4 children underwent audiological assessment in the age of 3 and 6 months. The most frequently hearing thresholds were registered between 35 and 55 dB that corresponds to mild-to-moderate hearing impairment. The average age of diagnostics was 7.9 years (ranged from 3 months to 45 years). In the majority of patients the audiological profiles were flat or descending with elevation of thresholds at middle and high frequencies and relatively preserved thresholds at low frequencies. Hearing thresholds are symmetric and stable with age.
STRC-linked hearing loss is congenital, of mild and moderate severity. Special clinical and genetic approach for children who failed newborn hearing screening with mild-to-moderate hearing loss is necessary.
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•The frequent reason of mild-to-moderate hearing loss is the deletions/mutations of the gene STRC encoding stereocilin protein.
Nowadays, due to universal newborn hearing screening (UNHS) the number of children with mild-to-moderate hearing loss diagnosed in the first year of life has increased significantly. Aside from that, ...identification of the genetic cause improves the genetic counselling of the families and allows to reveal possible comorbidities which may need a special approach.
To present the characteristics of the early audiologic phenotype in hearing impaired patients with biallelic mutations in the USH2A gene based on systematic analysis of the audiological data.
13 patients with mutations in the USH2A gene underwent audiological examination. Most of them were found among a large group of infants with bilateral nonsyndromic sensorineural hearing loss (SNHL) examined under 12 months.
Eight out of eleven children failed UNHS and were initially diagnosed as having bilateral nonsyndromic SNHL. Seven children underwent an audiological assessment before the age of 9 months. The earliest audiological examination was carried out at 1 and 3 months. The children with pathogenic variants in the USH2A gene in our examined group were identified in the first year of life via UNHS. The hearing threshold levels (HTL) for the USH2A group are compactly distributed between 51.25 dB and 66.25 dB, quartiles are 54 dB and 63.4 dB, with a median of 60 dB. The audiological profile of patients with biallelic USH2A mutations differs from audiograms of patients who had STRC-related hearing loss. We have not found any significant elevation in hearing thresholds in the first decade of life. We also estimated the prevalence of the USH2A and STRC mutations among GJB2-negative infants with bilateral nonsyndromic SNHL examined under 12 months, and it was 7.5% and 16.1%, respectively.
According to our results, the early hearing phenotype in pediatric patients with biallelic mutations in the USH2A- gene is characterized by nonsyndromic mild-to-moderate SNHL in the first decade of life. Our results indicate that the presence of mutations in the USH2A or STRC genes can be expected in a child with congenital mild-to-moderate nonsyndromic SNHL. This information is of practical importance for parents, as they have to know the prognosis of hearing loss for their child from the very beginning. Post-screening follow-up should include adequate clinical, genetic, and social support for children and their parents.
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•Тhe early hearing phenotype in patients with biallelic mutations in the USH2A gene characterized by nonsyndromal mild-to-moderate SNHL in the first decade of life.•Children with biallelic mutations in the USH2A gene failed universal newborn hearing screening (UNHS).•The earliest audiological assessment in patients with biallelic mutations in the USH2A was performed at the age 1 and 3 months.•The audiological profile of USH2A biallelic mutations differ from audiograms of the patients who had the STRC-linked hearing loss.
Abstract
This article aims to highlight the fact about the influence of European education on the work of the Russian architect with German roots, Robert Marfeld. On the basis of the collected ...bibliographic and archival materials, his projects and the work of his teacher - the famous Austrian architect Theophil Hansen, who taught a Master class at the Academy of Fine Arts in Vienna, worked with the greatest Austrian architects of the mid-19th century - are studied. In this context, a project of a vocational school in Irkutsk, carried out by Marfeld, is considered. The stylistic features of Marfeld’s architecture, especially in the initial period of creativity, are in many ways similar to the architecture of Hansen and his school. This is also due to the trends in architecture and construction of that period, especially in Germany and the Austro-Hungarian monarchy. Leading Russian architects were educated in Europe. European architects taught in St. Petersburg. Thus, the work of German and Austrian architects in Russia and in Irkutsk played a significant role in the formation of architectural identity, which contains many different characteristics, which was highlighted in previous articles by the authors, but also features inherent in the styles developed by the German and Austrian architectural schools.
During a 2-year period in 2005–2007, we conducted surveillance of group A rotaviruses and other enteric agents among patients hospitalized with acute gastroenteritis in 8 different cities of the ...Russian Federation. Fecal specimens were gathered from 3208 children (including 2848 children aged <5 years) and 1354 adults who were admitted to hospitals in Moscow, St. Petersburg, Chelyabinsk, Nizhnii Novgorod, Tyumen, Khabarovsk, Makhachkala, and Yakutsk. Polymerase chain reaction was performed to detect rotaviruses of groups A and C, noroviruses of genogroups I and II, astrovirus, sapovirus, and enteric adenoviruses (group F). Group A rotavirus was the most common viral pathogen detected among children aged <5 years (43.6%), followed by norovirus (12.5%), whereas norovirus was the pathogen most commonly detected in adults (11.9%). P and G genotypes were determined for 515 rotavirus specimens, and the most prevalent genotypes were G1P8 (44.9%), G4P8 (40.0%), G2P4 (8.5%), and G3P8 (6.6%). This study is the first multicenter study of rotaviruses in the Russian Federation and documents the important burden of disease caused by this pathogen, which soon may be preventable by vaccination
Halloysite/magnetite composite was synthesized by chemical coprecipitation. To evaluate the crystal structure, texture, surface morphology, and magnetization of the composite, electron microscopy, ...low-temperature nitrogen adsorption–desorption, X-ray diffraction analysis, and magnetic measurements were used. Granulometric analysis of the obtained materials showed that larger particles appear when halloysite is modified with magnetite. It was revealed that the studied samples of halloysite and composite belong to mesoporous bodies. An increase in the size of magnetite crystallites was found in the structure of magnetized clay. It is shown that samples of magnetized halloysite are characterized by higher values of the coercive force and lower values of the specific saturation magnetization compared to those found for magnetite.
The risks of propagation of pollutants from flare installations when flaring associated petroleum gas in the oil production area of the Tomsk region were analyzed on the basis of remote optical data ...from
Sentinel-2
and lidar data from CALIPSO. The horizontal fields of dispersion of pollutants over flare installations of the following fields are given: Pervomayskoye, Olenye, Stolbovoe, Katylginskoe, Lomovoe, Zapadno-Katylginskoe, and Luginetskoe. The areas of vegetation cover located in the zones of dispersion of pollutants from the flares are calculated. The vertical profiles of the propagation of impurities are given according to the CALIOP lidar data, reflecting aerosol pollution of the atmosphere in the area of flare installations of the fields considered in this work.
In many mammals, play is one of the most conspicuous behaviors during early development, but with notable inter‐individual variation even within the same litter. We investigated predictors of such ...variation in the Eurasian lynx (Lynx lynx), with a focus on potential effects of cubs' early body mass on the frequency of initiating play. We studied 45 cubs from 18 litters, kept in enclosures together with their mother. Observations started when cubs began to leave the natal den (around postnatal day 30) and lasted until weaning (around postnatal day 90). Individual differences in play were consistent over time, across all cubs as well as among littermates. The initiation of different play categories – with siblings, with the mother and solitary play – was positively associated and showed a similar developmental pattern. Cubs' body mass was positively associated with the frequency of play events; heavier cubs initiated play more often than lighter ones. This is consistent with the surplus resource theory, that is, that heavier young might have more energy resources available to allocate to play. Alternatively, lighter cubs may have initiated play less often to avoid asymmetrical rough‐and‐tumble interactions with their heavier siblings. Additionally, we found that offspring from middle‐age mothers initiated play more frequently than offspring from younger or older mothers. As cubs from middle‐age mothers had higher growth rates, this finding is again consistent with the surplus resource theory. Important questions for future research are whether such stable individual differences in play during early development correlate with other behavioral traits and translate into individual differences in behavior in later life.
Play is one of the most conspicuous behaviors during early development in many mammalian species, and there can be notable differences in the level of play activity among individuals. We attempted to understand such individual variation in Eurasian lynx (Lynx lynx) cubs, in particular by looking at possible effects of body mass. Individual differences in body mass across all cubs as well as relative differences among littermates were positively associated with frequency of play, that is, heavier cubs initiated play events more often than lighter cubs. This could be explained by the fact that heavier cubs might have had more energy resources available to allocate to play. We suggest, however, an alternative explanation, that lighter cubs may have been more passive in initiating play to avoid asymmetrical rough‐and‐tumble interactions with their heavier siblings.
Currently, agricultural enterprises are offered many conveyors of various typesfor the mechanization of loading and unloading works during cropmovement. The article presents studies of a method of ...increasing performance of a screw type conveyor allowing to create a small-sized design by increasing its revolutions. It investigates workmechanism, describesoperational technology of conveyors-grain and work disadvantages, namely, problematicgrain transportation over long distances along a spatial route or complication of technological scheme. Loading directly from pile may require manual labor or additional equipment. It is noted that increase in performance with increase in rotor revolutions (from 400 to 1100 rpm) occurs up to a point, after which revolutions increase, and performance decreases. In order to increase screw performance, it is necessary to accelerate material axial advance, i.e. to stretch ascending and, especially, falling material trajectorybranches at high speeds, with bulky material (grain), cast by centrifugal force to inner pipe surface, filling the grooves. Since their locationis close to each other (at 30°), surface braking layer is formed, which decreases circumferential speed component of absolute movement of grain andincreases the axial one. In order to increase screw performance, it is necessary to accelerate material axial advance, i.e. stretch ascending and, especially, falling material trajectorybranches. Further studies will contribute to finding new ways to increase speed coefficient Kυ and coefficient ψ and create high-speed, high-performance, and small-sized screw conveyors-grain loaders.
Analysis of the age-related dynamics of olfactory behavior in the odor preference and food search testsshowed that all male Wistar rats, regardless of age, preferred valerian essential oil, whose ...components have the properties of pheromones in rodents, when given a selection of eight essential oils; young rats displayed better food-seeking results than adult and old animals. Acute prenatal hypoxia (PH) on E14 (7% O
2
for 3 h) led to impairment of the valerian odor preference at all ages studied and to decreased productivity of food searches. Neurodegenerative processes were seen in the piriform cortex after PH, with reductions in the number of neurons and increases in glial elements. We have previously observed these changes in the entorhinal cortex and hippocampus, but not in the olfactory bulbs. This suggests that PH-induced decreases in olfactory function in rats may result from impairments to the formation of the central elements of the analyzer during the first months of postnatal ontogeny.
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