The recombinational properties of long GAA·TTC repeating sequences were analyzed in Escherichia coli to gain further insights into the molecular mechanisms of the genetic instability of this tract as ...possibly related to the etiology of Friedreich's ataxia. Intramolecular and intermolecular recombination studies showed that the frequency of recombination between the GAA·TTC tracts was as much as 15 times higher than the non-repeating control sequences. Homologous, intramolecular recombination between GAA·TTC tracts and GAAGGA·TCCTTC repeats also occurred with a very high frequency (∼0.8%). Biochemical analyses of the recombination products demonstrated the expansions and deletions of the GAA·TTC repeats. These results, together with our previous studies on the CTG·CAG sequences, suggest that the recombinational hot spot characteristics may be a common feature of all triplet repeat sequences. Unexpectedly, we found that the recombination properties of the GAA·TTC tracts were unique, compared with CTG·CAG repeats, because they depended on the DNA secondary structure polymorphism. Increasing the length of the GAA·TTC repeats decreased the intramolecular recombination frequency between these tracts. Also, a correlation was found between the propensity of the GAA·TTC tracts to adopt the sticky DNA conformation and the inhibition of intramolecular recombination. The use of novobiocin to modulate the intracellular DNA topology, i.e. the lowering of the negative superhelical density, repressed the formation of the sticky DNA structure, thereby restoring the expected positive correlation between the length of the GAA·TTC tracts and the frequency of intramolecular recombination. Hence, our results demonstrate that sticky DNA exists and functions in E. coli.
Introduction: The presence of background HCV
infection cannot be overestimated in view of the prevalence
of chronic hepatitis C and the risk of adverse outcomes
of this disease. Purpose of this study ...was to evaluate
the effectiveness of the combined use of antiviral therapy
(Roferon + Vero-Ribavirin) and resort factors in patients
with chronic hepatitis C in the phase of replication.
Material and methods: We observed 48 patients with
chronic hepatitis C; the minimum level of activity of the
process defined the phase of replication. Markers of HCV
infection were determined by enzyme linked immunosorbent
assay (ELISA) (a-HCV and HCV-Ig M). HCV RNA
was determined twice by the polymerase chain reaction
(PCR). Genotyping of hepatitis C virus was performed.
Biochemical blood analysis and the study of HCV infection
markers were carried out four times. Results of therapy
were assessed immediately after the end of the resort
(spa) treatment, then at 3, 6 and 12 months after starting
treatment. At 12 months after starting treatment, all the
observed patients had persistent clinical and biochemical
remission. Elimination of the virus from the blood was
noted in 56% of the control group and 74% of patients in
the study group.
Conclusions: For patients with moderately active HCV, the
replication phase was characterized by asthenic-vegetative
syndrome (100% of patients) with severe depression (22.92%), pain (77.08%) and dyspeptic syndrome (33.33%),
moderate hypertransferaseemia (100%), slightly pronounced
cholestasis (33% of patients), and signs of mesenchymal-
inflammatory response.
Background. The physical benefits of fitness for middle-aged women are well-known. Unlike the usual training sessions, aquafitness occupies a special place among the types of health-related exercise ...training. Its health-enhancing effect results from the activation of the body's functional systems, the gravitational unloading of the musculoskeletal system, high energy expenditures, and overall body hardening effect.
The objective of this study was to evaluate the health-enhancing effects of an aquafitness program on the functional indicators and physical fitness of early adulthood women.
Materials and methods. Theoretical analysis and generalization of scientific and methodological literature, anthropometric techniques, pedagogical methods, and methods of mathematical statistics were used. The functional status of the body was assessed with the indices characterizing the function of the cardiorespiratory system, which are commonly used. The study was conducted at the Sport Life fitness club, Chernivtsi. The study involved 48 women aged 21-31 with an average age of 26.3 years. The subjects took part in a six-month aquafitness program consisting of 60-min sessions, three times a week. The program was developed by the authors and included aquatic stretching, body shaping and bodybuilding exercise, aquadance, aquatic gymnastics, and aqua tae-bo.
Results. After participation in the exercise program: vital capacity increased from 45.96±4.69 to 48.88±0.68; strength index increased from 35.80±1.07 to 43.26±0.71; Robinson's index increased from 85.72±12.34 to 89.63±10.11; Shtange test increased from 30.28±10.32 to 37.78±12.34; Hench test changed from 16.48±4.24 to 25.19±4.58; Kerdo index decreased from 5.23±0.74 to 0.88±0.38; and Rufier's test decreased from 12.21±4.26 to 8.03±2.14. The assessment of somatic health of the women showed a significant improvement (p<0.05). Positive changes in the autonomic system were detected.
Conclusion. The developed aquafitness program can be an effective tool for health improvement and body weight management in early adulthood women.
Background. The effect of geomagnetism on human immunity has so far been studied through long-term observations. We set ourselves the goal of detecting the immediate immunotropic effects of the ...Earth's magnetic field by analyzing the relationships between immunity parameters and the geomagnetic Ap-index. Material and methods. The object of observation were 74 patients with multiple sclerosis and 14 patients with radiculopathies, who in the period from September 2014 to November 2018 conducted a one-time assessment of immune status by the relative content in the blood of lymphocytes of CD3+, CD4+, CD8+, CD25+, CD56+ and CD19+ phenotypes and serum level of Immunoglobulines M, G, A as well as CIC and IL-1β. On the day of blood capture and during the previous 7 days, retrospectively recorded the geomagnetic Ap-index, using a publicly available information resource http://wdc.kugi.kyoto-u.ac.jp/kp/index.html. Results. During the week, the average level of Ap-index ranged from 12÷20 nT. The correlation coefficients between the Ap-index on the day of blood collection and 1, 3 and 7 days before it and the level of CD3+CD4+ lymphocytes were -0,57; -0,48; -0,55 і -0,52 respectively, while on other days were in the range of -0,35÷0,05. In contrast, with the level of CD56+ lymphocytes Ap-index correlates positively and almost mirror (0,56; 0,43; 0,54 і 0,57 respectively and 0,34÷-0,08), due to the reciprocity of their levels (r=-0,80). Also positive, but much weaker, correlates the Ap-index with the level of CD25+ lymphocytes (0,35; 0,25; 0,45 і 0,31 respectively and 0,22÷-0,14). In contrast, with the level of IL-1β Ap-index correlates significantly only on the day of blood collection and 2 days before (r=0,21 and 0,31 respectively), and with other registered parameters of immunity the correlation is insignificant. The canonical correlation between Ap-indices for 7 days before and on the day of blood collection, on the one hand, and the levels of CD4+, CD56+, CD25+ and CD8+ lymphocytes and the concentration of IgM and IL-1β - on the other hand, was very strong: R=0,741; R2=0,549; χ2(42)=130; p<10-6. Conclusion. Disturbances of the geomagnetic field (Ap-index) has a significant immediate modulating effect on the level of immune parameters in the blood, mostly T-helpers (suppressor) and natural killers (enhancing).
CO 2 optical fiber sensors based on polymer active materials are presented in this paper. Ethyl cellulose was proven to be a good candidate for a matrix material of the sensor, since it gives porous, ...thick and very sensitive layers. Low-cost sensors based on polymer optical fibers have been elaborated. Sensors have been examined for their sensitivity to CO 2 , temperature and humidity. Response time during cyclic exposures to CO 2 have been also determined. Special layers exhibiting irreversible change of color during exposure to carbon dioxide have been developed. They have been verified for a possible use in smart food packaging.
Objective
Frataxin (FXN) is a highly conserved mitochondrial protein. Reduced FXN levels cause Friedreich ataxia, a recessive neurodegenerative disease. Typical patients carry GAA repeat expansions ...on both alleles, while a subgroup of patients carry a missense mutation on one allele and a GAA repeat expansion on the other. Here, we report that selected disease‐related FXN missense mutations impair FXN localization, interaction with mitochondria processing peptidase, and processing.
Methods
Immunocytochemical studies and subcellular fractionation were performed to study FXN import into the mitochondria and examine the mechanism by which mutations impair FXN processing. Coimmunoprecipitation was performed to study the interaction between FXN and mitochondrial processing peptidase. A proteasome inhibitor was used to model traditional therapeutic strategies. In addition, clinical profiles of subjects with and without point mutations were compared in a large natural history study.
Results
FXNI154F and FXNG130V missense mutations decrease FXN81–210 levels compared with FXNWT, FXNR165C, and FXNW155R, but do not block its association with mitochondria. FXNI154F and FXNG130V also impair FXN maturation and enhance the binding between FXN42–210 and mitochondria processing peptidase. Furthermore, blocking proteosomal degradation does not increase FXN81–210 levels. Additionally, impaired FXN processing also occurs in fibroblasts from patients with FXNG130V. Finally, clinical data from patients with FXNG130V and FXNI154F mutations demonstrates a lower severity compared with other individuals with Friedreich ataxia.
Interpretation
These data suggest that the effects on processing associated with FXNG130V and FXNI154F mutations lead to higher levels of partially processed FXN, which may contribute to the milder clinical phenotypes in these patients.
Friedreich's ataxia (FRDA) is an autosomal recessive neurodegenerative disease caused by reduced expression of the mitochondrial protein frataxin (FXN). Most FRDA patients are homozygous for large ...expansions of GAA repeat sequences in intron 1 of FXN, while a fraction of patients are compound heterozygotes with a missense or nonsense mutation in one FXN allele and expanded GAAs in the other. A prevalent missense mutation among FRDA patients changes a glycine at position 130 to valine (G130V). Herein, we report generation of the first mouse model harboring a Fxn point mutation. Changing the evolutionarily conserved glycine 127 in mouse Fxn to valine results in a failure to thrive phenotype in homozygous animals and a substantially reduced number of offspring. Like G130V in FRDA, the G127V mutation results in a dramatic decrease of Fxn protein without affecting transcript synthesis or splicing. FxnG127V mouse embryonic fibroblasts exhibit significantly reduced proliferation and increased cell senescence. These defects are evident in early passage cells and are exacerbated at later passages. Furthermore, increased frequency of mitochondrial DNA (mtDNA) lesions and fragmentation are accompanied by marked amplification of mtDNA in FxnG127V cells. Bioenergetics analyses demonstrate higher sensitivity and reduced cellular respiration of FxnG127V cells upon alteration of fatty acid availability. Importantly, substitution of FxnWT with FxnG127V is compatible with life and cellular proliferation defects can be rescued by mitigation of oxidative stress via hypoxia or induction of the NRF2 pathway. We propose FxnG127V cells as a simple and robust model for testing therapeutic approaches for FRDA.
We report for the first time, the fast inscription of high-quality Bragg gratings in highly birefringent microstructured polymer optical fibers by the phase mask method using 248-nm UV radiation. The ...fibers birefringence is created through a special design of the structure of holes through the fiber. A Bragg grating in these type of fibers allows the creation of two reflection peaks, where the peak separation is related to the phase birefringence.
RNA metabolism is a major contributor to the pathogenesis of clinical disorders associated with premutation size alleles of the fragile X mental retardation (FMR1) gene. Herein, we determined the ...structural properties of numerous FMR1 transcripts harboring different numbers of both CGG repeats and AGG interruptions. The stability of hairpins formed by uninterrupted repeat-containing transcripts increased with the lengthening of the repeat tract. Even a single AGG interruption in the repeated sequence dramatically changed the folding of the 5′UTR fragments, typically resulting in branched hairpin structures. Transcripts containing different lengths of CGG repeats, but sharing a common AGG pattern, adopted similar types of secondary structures. We postulate that interruption-dependent structure variants of the FMR1 mRNA contribute to the phenotype diversity, observed in premutation carriers.
Friedreich's ataxia (FRDA) represents a rare neurodegenerative disease caused by expansion of GAA trinucleotide repeats in the first intron of the FXN gene. The number of GAA repeats in FRDA patients ...varies from approximately 60 to <1000 and is tightly correlated with age of onset and severity of the disease symptoms. The heterogeneity of Friedreich's ataxia stresses the need for a large cohort of patient samples to conduct studies addressing the mechanism of disease pathogenesis or evaluate novel therapeutic candidates. Herein, we report the establishment and characterization of an FRDA fibroblast repository, which currently includes 50 primary cell lines derived from FRDA patients and seven lines from mutation carriers. These cells are also a source for generating induced pluripotent stem cell (iPSC) lines by reprogramming, as well as disease-relevant neuronal, cardiac, and pancreatic cells that can then be differentiated from the iPSCs. All FRDA and carrier lines are derived using a standard operating procedure and characterized to confirm mutation status, as well as expression of FXN mRNA and protein. Consideration and significance of creating disease-focused cell line and tissue repositories, especially in the context of rare and heterogeneous disorders, are presented. Although the economic aspect of creating and maintaining such repositories is important, the benefits of easy access to a collection of well-characterized cell lines for the purpose of drug discovery or disease mechanism studies overshadow the associated costs. Importantly, all FRDA fibroblast cell lines collected in our repository are available to the scientific community.
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