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BACKGROUND: Bdelloid rotifers are micro-invertebrates distributed worldwide, from temperate latitudes to the most extreme areas of the planet like Antarctica or the Atacama Desert. They have colonized any habitat where liquid water is temporarily available, including terrestrial environments such as soils, mosses, and lichens, tolerating desiccation and other types of stress such as high doses of ionizing radiation (IR). It was hypothesized that bdelloid desiccation and radiation resistance may be attributed to their potential ability to repair DNA double-strand breaks (DSBs). Here, these properties are investigated and compared among nine bdelloid species collected from both mild and harsh habitats, addressing the correlation between the ability of bdelloid rotifers to survive desiccation and their capacity to repair massive DNA breakage in a phylogenetically explicit context. Our research includes both specimens isolated from habitats that experience frequent desiccation (at least 1 time per generation), and individuals sampled from habitats that rarely or never experienced desiccation. RESULTS: Our analysis reveals that DNA repair prevails in somatic cells of both desiccation-tolerant and desiccation-sensitive bdelloid species after exposure to X-ray radiation. Species belonging to both categories are able to withstand high doses of ionizing radiation, up to 1000 Gy, without experiencing any negative effects on their survival. However, the fertility of two desiccation-sensitive species, Rotaria macrura and Rotaria rotatoria, was more severely impacted by low doses of radiation than that of desiccation-resistant species. Surprisingly, the radioresistance of desiccation-resistant species is not related to features of their original habitat. Indeed, bdelloids isolated from Atacama Desert or Antarctica were not characterized by a higher radioresistance than species found in more temperate environments. CONCLUSIONS: Tolerance to desiccation and radiation are supported as ancestral features of bdelloid rotifers, with a group of species of the genus Rotaria having lost this trait after colonizing permanent water habitats. Together, our results provide a comprehensive overview of the evolution of desiccation and radiation resistance among bdelloid rotifers.
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Dessecação , Rotíferos , Humanos , Animais , Rotíferos/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA , ÁguaRESUMO
OBJECTIVE: The aim: Analyse the impact and effectiveness of cognitive-behavioural therapy in patients with NAFLD on the background of AO on indicators of lipid and carbohydrate metabolism. PATIENTS AND METHODS: Materials and methods: 85 patients with NAFLD and obesity of the 1st degree (42 women, 43 men) were examined. All patients were divided into two clinical groups: 1st group (research) - 48 people, who underwent a course of CBT for 6 months; the control group - 37 people, who followed only diet therapy, recommended physical activity, without involvement in CBT. The general clinical examination of patients consisted of the measurement of anthropometric and physiological indicators, the study of lipid and carbohydrate profile indicators. RESULTS: Results: After a 6-month course of CBT, a decrease in the atherogenic coefficient (AC) was recorded in the patients of the 1st group in 2.29 times (p=0.037<0.05), the number of patients with hypertension of the 1st degree decreased in 1.8 times (p=0.0047<0.05) in comparison with the initial indicators (on the 1st day) and amount of patients with normal blood pressure of the 1st group increased by 2.4 times (p=0.0115<0.05) compared to the control group. CONCLUSION: Conclusions: The course of CBT should be an integral component in the program for the management of obese patients to optimize not only the psycho-emo¬tional condition, but also to correct lipid and carbohydrate metabolism indicators, reduce the risk of developing cardiovascular and neurological complications.
Assuntos
Terapia Cognitivo-Comportamental , Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/terapia , Obesidade Abdominal/complicações , Obesidade/complicações , Obesidade/terapia , Metabolismo dos Carboidratos , Lipídeos , Índice de Massa CorporalRESUMO
OBJECTIVE: The aim: Identify the types of eating behaviour in overweight and obesity depending on gender and age. PATIENTS AND METHODS: Materials and methods: A survey of 210 people (men -105, women -105) was conducted. The age of women ranged from 19 to 60 years, the average age was 41.5 ± 11.2 years. The age of men ranged from 22 to 60 years, the average age was 42.3 ± 12.3 years. The examined patients were divided into two clinical groups: group I - 70 people (women - 35, men - 35) with overweight. BMI of persons of the I group from 25.8 kg / m2 to 29,3 kg / m2 (BMTmid. = 27,5 ± 1,31 kg / m2); Group II - 72 people with 1st degree obesity (women -36, men - 36). Evaluation of eating disorders was carried out using the DEBQ questionnaire (Nederland) adapted to the purpose of the study. RESULTS: Results: In patients of groups I and II healthy type of eating behaviour was recorded less often than in control groups, 5.38 times (D = 13.561, p = 0.002 <0.05) and 10.45 times (D = 21.043, p = 0.022 <0.05), respectively. In group I, the restrictive type of EB among women occurred 1.7 times more often than in men (D = 0.852, p = 0.001). In group II, the restrictive type of EB among women was observed 1.3 times more often than in men (D = 0.382, p = 0.005). CONCLUSION: Conclusions: Restrictive eating behaviour disorders are one of the leading factors in the development of overweight and obesity. Correction of eating disorders in obese people must be carried out taking into account the gender and age characteristics of the patient, to obtain positive results for a shorter course of treatment.
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Comportamento Alimentar , Obesidade , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Inquéritos e Questionários , Adulto JovemRESUMO
Despite its inherent costs, sexual reproduction is ubiquitous in nature, and the mechanisms to protect it from a competitive displacement by asexuality remain unclear. Popular mutation-based explanations, like the Muller's ratchet and the Kondrashov's hatchet, assume that purifying selection may not halt the accumulation of deleterious mutations in the nonrecombining genomes, ultimately leading to their degeneration. However, empirical evidence is scarce and it remains particularly unclear whether mutational degradation proceeds fast enough to ensure the decay of clonal organisms and to prevent them from outcompeting their sexual counterparts. To test this hypothesis, we jointly analysed the exome sequences and the fitness-related phenotypic traits of the sexually reproducing fish species and their clonal hybrids, whose evolutionary ages ranged from F1 generations to 300 ky. As expected, mutations tended to accumulate in the clonal genomes in a time-dependent manner. However, contrary to the predictions, we found no trend towards increased nonsynonymity of mutations acquired by clones, nor higher radicality of their amino acid substitutions. Moreover, there was no evidence for fitness degeneration in the old clones compared with that in the younger ones. In summary, although an efficacy of purifying selection may still be reduced in the asexual genomes, our data indicate that its efficiency is not drastically decreased. Even the oldest investigated clone was found to be too young to suffer fitness consequences from a mutation accumulation. This suggests that mechanisms other than mutation accumulation may be needed to explain the competitive advantage of sex in the short term.
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Evolução Biológica , Reprodução , Animais , Emoções , Genoma , Modelos Genéticos , Mutação , Reprodução/genética , Reprodução Assexuada/genéticaRESUMO
OBJECTIVE: Introduction: Medico-social significance of osteoarthritis is due to a number of factors, one of which is associated with the need for long-term anti-inflammatory therapy, which is associated with undesirable side effects. The aim: Identify the features of the course of chronic gastritis in patients taking selective NSAIDs for osteoarthritis. PATIENTS AND METHODS: Materials and methods: Were examined 122 patients with osteoarthrosis, who had verified chronic gastritis in the anamnesis (50 males and 72 females), aged from 42 to 64. Control group included 40 patients with osteoarthrosis without gastroduodenal zone pathology in the anamnesis. For arthralgia relief, patients were prescribed to intake meloxicam (average dose - 12.5±1.39 mg/day) or nimesulide (average dose - 150±14.91 mg/day). RESULTS: Results: It was determined that prescription of selective NSAIDs (meloxicam and nimesulide) raised the risk of NSAIDs gastropathy/dyspepsia in 2.9 times (P<0.03) in patients with chronic gastritis in the anamnesis than in patients without associated gastroduodenal zone pathology. Atrophy of gastric mucous membrane was associated with higher risks (P>0.05) of erosive gastropathy. CONCLUSION: Conclusions: With the purpose of gastropathy prevention upon taking NSAIDs, patients with chronic gastritis in the anamnesis are recommended to undergo gastroprotective therapy.
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Gastrite , Osteoartrite , Adulto , Anti-Inflamatórios não Esteroides , Comorbidade , Feminino , Gastrite/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/complicações , Osteoartrite/epidemiologia , Osteoartrite/prevenção & controle , Prevenção Secundária , Valores SociaisRESUMO
OBJECTIVE: Introduction: Hepatitis C virus (HCV) infection is a major global problem. According to WHO, 150-200 million people globally have hepatitis C infection. Even though HCV infection morbidity rate in children is relatively low in comparison with the adult population, approximately 5 million children in the world have active HCV. There is a number of differences between HCV infection in adults and in children. However, the data pertaining to this issue is controversial. The aim: Research, analysis and synthesis of information from contemporary literature on transmission of infection and characteristics of the course of HCV infection in children. PATIENTS AND METHODS: Materials and methods: Analysis and synthesis of information from contemporary literature on transmission of infection and characteristics of the course of HCV infection in children were conducted. CONCLUSION: Conclusions: Information from literature of the latest years on peculiarities of infection, disease course and complications of HCV infection in children was analyzed and summarized in this article.
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Hepacivirus , Hepatite C , Criança , Progressão da Doença , HumanosRESUMO
Although sexual reproduction is ubiquitous throughout nature, the molecular machinery behind it has been repeatedly disrupted during evolution, leading to the emergence of asexual lineages in all eukaryotic phyla. Despite intensive research, little is known about what causes the switch from sexual reproduction to asexuality. Interspecific hybridization is one of the candidate explanations, but the reasons for the apparent association between hybridization and asexuality remain unclear. In this study, we combined cross-breeding experiments with population genetic and phylogenomic approaches to reveal the history of speciation and asexuality evolution in European spined loaches (Cobitis). Contemporary species readily hybridize in hybrid zones, but produce infertile males and fertile but clonally reproducing females that cannot mediate introgressions. However, our analysis of exome data indicates that intensive gene flow between species has occurred in the past. Crossings among species with various genetic distances showed that, while distantly related species produced asexual females and sterile males, closely related species produce sexually reproducing hybrids of both sexes. Our results suggest that hybridization leads to sexual hybrids at the initial stages of speciation, but as the species diverge further, the gradual accumulation of reproductive incompatibilities between species could distort their gametogenesis towards asexuality. Interestingly, comparative analysis of published data revealed that hybrid asexuality generally evolves at lower genetic divergences than hybrid sterility or inviability. Given that hybrid asexuality effectively restricts gene flow, it may establish a primary reproductive barrier earlier during diversification than other "classical" forms of postzygotic incompatibilities. Hybrid asexuality may thus indirectly contribute to the speciation process.
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Cipriniformes/genética , Especiação Genética , Hibridização Genética , Reprodução Assexuada/genética , Zigoto/fisiologia , Animais , Cruzamentos Genéticos , Feminino , Variação Genética , Genética Populacional , Geografia , Haplótipos/genética , Masculino , Isolamento Reprodutivo , Especificidade da EspécieRESUMO
Based on molecular data three major clades have been recognized within Bilateria: Deuterostomia, Ecdysozoa, and Spiralia. Within Spiralia, small-sized and simply organized animals such as flatworms, gastrotrichs, and gnathostomulids have recently been grouped together as Platyzoa. However, the representation of putative platyzoans was low in the respective molecular phylogenetic studies, in terms of both, taxon number and sequence data. Furthermore, increased substitution rates in platyzoan taxa raised the possibility that monophyletic Platyzoa represents an artifact due to long-branch attraction. In order to overcome such problems, we employed a phylogenomic approach, thereby substantially increasing 1) the number of sampled species within Platyzoa and 2) species-specific sequence coverage in data sets of up to 82,162 amino acid positions. Using established and new measures (long-branch score), we disentangled phylogenetic signal from misleading effects such as long-branch attraction. In doing so, our phylogenomic analyses did not recover a monophyletic origin of platyzoan taxa that, instead, appeared paraphyletic with respect to the other spiralians. Platyhelminthes and Gastrotricha formed a monophylum, which we name Rouphozoa. To the exclusion of Gnathifera, Rouphozoa and all other spiralians represent a monophyletic group, which we name Platytrochozoa. Platyzoan paraphyly suggests that the last common ancestor of Spiralia was a simple-bodied organism lacking coelomic cavities, segmentation, and complex brain structures, and that more complex animals such as annelids evolved from such a simply organized ancestor. This conclusion contradicts alternative evolutionary scenarios proposing an annelid-like ancestor of Bilateria and Spiralia and several independent events of secondary reduction.
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Genômica/métodos , Helmintos/classificação , Helmintos/genética , Animais , Evolução Molecular , Genoma Helmíntico , Filogenia , Platelmintos/classificação , Platelmintos/genéticaRESUMO
In natural, permanently frozen habitats, some organisms may be preserved for hundreds to tens of thousands of years. For example, stems of Antarctic moss were successfully regrown from an over millennium-old sample covered by ice for about 400 years1. Likewise, whole campion plants were regenerated from seed tissue preserved in relict 32,000-year-old permafrost2, and nematodes were revived from the permafrost of two localities in northeastern Siberia, with source sediments dated over 30,000 years BP3. Bdelloid rotifers, microscopic multicellular animals, are known for their ability to survive extremely low temperatures4. Previous reports suggest survival after six to ten years when frozen between -20° to 0°C4-6. Here, we report the survival of an obligate parthenogenetic bdelloid rotifer, recovered from northeastern Siberian permafrost radiocarbon-dated to â¼24,000 years BP. This constitutes the longest reported case of rotifer survival in a frozen state. We confirmed the finding by identifying rotifer actin gene sequences in a metagenome obtained from the same sample. By morphological and molecular markers, the discovered rotifer belongs to the genus Adineta, and aligns with a contemporary Adineta vaga isolate collected in Belgium. Experiments demonstrated that the ancient rotifer withstands slow cooling and freezing (â¼1°C min-1) for at least seven days. We also show that a clonal culture can continuously reproduce in the laboratory by parthenogenesis.
Assuntos
Congelamento , Pergelissolo , Rotíferos/crescimento & desenvolvimento , Rotíferos/isolamento & purificação , Animais , Metagenoma , Partenogênese , Rotíferos/classificação , Rotíferos/genética , SibériaRESUMO
Bdelloid rotifers are a group of microscopic invertebrates known for their obligate parthenogenesis and exceptional resistance to extreme environments. Their diversity and distributions are poorly studied in Asia, especially in China. In order to better understand the species distribution and diversity of bdelloid rotifers in China, a scientific surveys of habitats was conducted with 61 samples (both terrestrial and aquatic habitats) from 11 provinces and regions of China, ranging from tropics to subtropics with a specific focus on poorly sampled areas (Oriental) during September 2017 to October 2018. A total of 59 morphospecies (including subspecies) were found, of which, thirty-nine morphospecies (including one genus) are new records for China, almost doubling the number of previous records. Four rare morphospecies (Adineta cf. acuticornis Haigh, A. beysunae Örstan, Habrotrocha ligula loxoglotta De Koning and H. serpens Donner) are depicted and redescribed, and an updated checklist of Chinese bdelloids with their location and ecological information is presented. This study provides new data from a large region of China, enriching the knowledge of bdelloid biodiversity, and their global biogeography.
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Despite recent great interest in glacier ecosystems in the continental Antarctic, little is known about their maritime counterparts. Our study presents descriptive data on cryoconite sediments and cryoconite holes on Ecology Glacier (King George Island) to accomplish three main objectives: (a) to identify main eukaryotic (algae, invertebrates) and prokaryotic (cyanobacteria) components of microbial communities; (b) to provide a "baseline" of community composition, organic matter and artificial contamination; and (c) to identify key abiotic factors that might be important in community assembly. Cryoconite holes were sampled along an altitudinal gradient of Ecology Glacier in January, mid Austral Summer 2017. Cryoconite holes located in lower altitude were deeper than those located in the middle and the highest altitude. Seventeen species of algae and cyanobacteria with biomass of 0.79 to 5.37 µg/cm3 have been found in sediments. Dominant species were cyanobacterial Pseudanabaena frigida and Bacillariophyceae Microcostaus sp. Biomass of Bacillariophyceae was significantly higher than that of Chlorophyta and Cyanobacteria. We found three species of rotifers (potentially two new to science) and for the first time a glacier dwelling Acari (suspension feeder, Nanorchestes nivalis). Organic matter content ranged from 5.4% to 7.6%. Investigated artificial radionuclides included 137Cs, 238Pu, 239+240Pu and 241Am. 210Pb seems to be related to organic matter content. Overall, cryoconite holes on Ecology Glacier present unique habitats that serve as biodiversity hotspots of psychrophiles, source of organic matter, matrices for radioactivity tracking and model for observing changes in supraglacial ecosystems in the maritime Antarctic.