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1.
Cell ; 182(5): 1186-1197.e12, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32841602

RESUMO

Experiences trigger transgenerational small RNA-based responses in C. elegans nematodes. Dedicated machinery ensures that heritable effects are reset, but how the responses segregate in the population is unknown. We show that isogenic individuals differ dramatically in the persistence of transgenerational responses. By examining lineages of more than 20,000 worms, three principles emerge: (1) The silencing each mother initiates is distributed evenly among her descendants; heritable RNAi dissipates but is uniform in every generation. (2) Differences between lineages arise because the mothers that initiate heritable responses stochastically assume different "inheritance states" that determine the progeny's fate. (3) The likelihood that an RNAi response would continue to be inherited increases the more generations it lasts. The inheritance states are determined by HSF-1, which regulates silencing factors and, accordingly, small RNA levels. We found that, based on the parents' inheritance state, the descendants' developmental rate in response to stress can be predicted.


Assuntos
Caenorhabditis elegans/genética , Padrões de Herança/genética , RNA Interferente Pequeno/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Interferência de RNA/fisiologia
2.
Cell ; 177(7): 1814-1826.e15, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31178120

RESUMO

It is unknown whether the activity of the nervous system can be inherited. In Caenorhabditis elegans nematodes, parental responses can transmit heritable small RNAs that regulate gene expression transgenerationally. In this study, we show that a neuronal process can impact the next generations. Neurons-specific synthesis of RDE-4-dependent small RNAs regulates germline amplified endogenous small interfering RNAs (siRNAs) and germline gene expression for multiple generations. Further, the production of small RNAs in neurons controls the chemotaxis behavior of the progeny for at least three generations via the germline Argonaute HRDE-1. Among the targets of these small RNAs, we identified the conserved gene saeg-2, which is transgenerationally downregulated in the germline. Silencing of saeg-2 following neuronal small RNA biogenesis is required for chemotaxis under stress. Thus, we propose a small-RNA-based mechanism for communication of neuronal processes transgenerationally.


Assuntos
Comportamento Animal , Caenorhabditis elegans , Neurônios/metabolismo , RNA de Helmintos , Pequeno RNA não Traduzido , Animais , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Neurônios/citologia , RNA de Helmintos/biossíntese , RNA de Helmintos/genética , Pequeno RNA não Traduzido/biossíntese , Pequeno RNA não Traduzido/genética
3.
Eur J Public Health ; 34(4): 666-675, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38905592

RESUMO

BACKGROUND: Somatic and germline genetic alterations are significant drivers of cancer. Increasing integration of new technologies which profile these alterations requires timely, equitable and high-quality genetic counselling to facilitate accurate diagnoses and informed decision-making by patients and their families in preventive and clinical settings. This article aims to provide an overview of genetic counselling legislation and practice across European Union (EU) Member States to serve as a foundation for future European recommendations and action. METHODS: National legislative databases of all 27 Member States were searched using terms relevant to genetic counselling, translated as appropriate. Interviews with relevant experts from each Member State were conducted to validate legislative search results and provide detailed insights into genetic counselling practice in each country. RESULTS: Genetic counselling is included in national legislative documents of 22 of 27 Member States, with substantial variation in legal mechanisms and prescribed details (i.e. the 'who, what, when and where' of counselling). Practice is similarly varied. Workforce capacity (25 of 27 Member States) and genetic literacy (all Member States) were common reported barriers. Recognition and/or better integration of genetic counsellors and updated legislation and were most commonly noted as the 'most important change' which would improve practice. CONCLUSIONS: This review highlights substantial variability in genetic counselling across EU Member States, as well as common barriers notwithstanding this variation. Future recommendations and action should focus on addressing literacy and capacity challenges through legislative, regulatory and/or strategic approaches at EU, national, regional and/or local levels.


Assuntos
União Europeia , Aconselhamento Genético , Neoplasias , Humanos , Aconselhamento Genético/legislação & jurisprudência , Neoplasias/genética , Testes Genéticos/legislação & jurisprudência
4.
Platelets ; 34(1): 2139365, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36325627

RESUMO

Activated platelets possess procoagulant activity expressing on their surface phosphatidylserine (PS), a substrate for assembling coagulation complexes. We examined the effects of platelets activated by different agonists on fibrin formation and thrombin generation and compared these effects with each other and with PS expression. Modified plasma recalcification assay was developed to assess platelet effects on fibrin formation. Washed human platelets were left intact or activated by A23187 ionophore, collagen, arachidonic acid, ADP or TRAP (Thrombin Receptor Activating Peptide) and spun down in 96-well plates. Plasma was then added, recalcified, and fibrin formation was monitored by light absorbance. Platelets prepared in the same way were tested for their effect on thrombin generation. PS expression was evaluated by flow cytometry using annexin V staining. Platelets significantly accelerated fibrin formation and thrombin generation. They shortened lag phase and increased maximum rate of plasma clotting, and increased peak and maximum rate of thrombin generation. In both tests platelets were presumably activated by endogenous thrombin formed in plasma after triggering coagulation reactions. However, pretreatment with exogenous agonists additionally increased platelet procoagulant activity. It reached the maximum after incubation with A23187, being lower with collagen and arachidonic acid and minimum with ADP and TRAP (the latter might be ineffective due to competition with endogenous thrombin). The effects of platelets activated by different agonists on fibrin formation and thrombin generation correlate with each other and correspond to PS expression on their surface.


Why was the study done? Platelets and blood coagulation system interact with each other in hemostasis and intravascular thrombosis.Direct platelet effects on fibrin formation (plasma clotting), the final stage of blood coagulation cascade, have been insufficiently studied.The work is aimed at developing a method for studying platelet participation in fibrin formation in blood plasma and investigating the influence of platelet agonists on this reaction.What is new? Platelets significantly accelerate fibrin formation and their activation with various agonists (thrombin, collagen, arachidonic acid) enhances these effects.Effects of platelets on fibrin formation correlated with their ability to stimulate thrombin generation in blood plasmaEffects of platelets on fibrin formation and thrombin generation correlated with the level of phosphatidylserine exposure on their surfaceWhat is the impact? This study provides further evidence that platelet procоagulant effects on fibrin formation should be considered in investigations of platelet involvement in hemostatic and thrombotic reactions and in the evaluation of the efficacy of antiplatelet drugs.


Assuntos
Plaquetas , Trombina , Humanos , Trombina/farmacologia , Trombina/metabolismo , Plaquetas/metabolismo , Fibrina/metabolismo , Calcimicina/metabolismo , Calcimicina/farmacologia , Ácido Araquidônico/farmacologia , Ácido Araquidônico/metabolismo , Fosfatidilserinas/metabolismo , Colágeno/farmacologia , Colágeno/metabolismo , Difosfato de Adenosina/farmacologia , Difosfato de Adenosina/metabolismo
5.
Biochemistry (Mosc) ; 88(8): 1126-1138, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37758312

RESUMO

Hyperglycemia is a hallmark of type 2 diabetes implicated in vascular endothelial dysfunction and cardiovascular complications. Many in vitro studies identified endothelial apoptosis as an early outcome of experimentally modeled hyperglycemia emphasizing cell demise as a significant factor of vascular injury. However, endothelial apoptosis has not been observed in vivo until the late stages of type 2 diabetes. Here, we studied the long-term (up to 4 weeks) effects of high glucose (HG, 30 mM) on human umbilical vein endothelial cells (HUVEC) in vitro. HG did not alter HUVEC monolayer morphology, ROS levels, NO production, and exerted minor effects on the HUVEC apoptosis markers. The barrier responses to various clues were indistinguishable from those by cells cultured in physiological glucose (5 mM). Tackling the key regulators of cytoskeletal contractility and endothelial barrier revealed no differences in the histamine-induced intracellular Ca2+ responses, nor in phosphorylation of myosin regulatory light chain or myosin light chain phosphatase. Altogether, these findings suggest that vascular endothelial cells may well tolerate HG for relatively long exposures and warrant further studies to explore mechanisms involved in vascular damage in advanced type 2 diabetes.

6.
Biochemistry (Mosc) ; 88(12): 2125-2136, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38462455

RESUMO

Expression of LOX-1 and NOX1 genes in the human umbilical vein endotheliocytes (HUVECs) cultured in the presence of low-density lipoproteins (LDL) modified with various natural dicarbonyls was investigated for the first time. It was found that among the investigated dicarbonyl-modified LDLs (malondialdehyde (MDA)-modified LDLs, glyoxal-modified LDLs, and methylglyoxal-modified LDLs), the MDA-modified LDLs caused the greatest induction of the LOX-1 and NOX1 genes, as well as of the genes of antioxidant enzymes and genes of proapoptotic factors in HUVECs. Key role of the dicarbonyl-modified LDLs in the molecular mechanisms of vascular wall damage and endothelial dysfunction is discussed.


Assuntos
Células Endoteliais , Lipoproteínas LDL , Humanos , Lipoproteínas LDL/metabolismo , Veias Umbilicais/metabolismo , Células Endoteliais/metabolismo , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismo , Expressão Gênica , Células Cultivadas , NADPH Oxidase 1/genética , NADPH Oxidase 1/metabolismo
7.
Graefes Arch Clin Exp Ophthalmol ; 261(1): 185-191, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35896678

RESUMO

PURPOSE: The most crucial step in deep anterior lamellar keratoplasty (DALK) is to achieve a bare Descemet's membrane. We aimed to assess a new femtosecond laser software that allows for a precise intrastromal tunnel creation for big bubble (BB) air injection using a real-time microscope-integrated optical coherence tomography. MATERIALS AND METHODS: A retrospective review of 61 eyes of 61 patients with keratoconus. Before introducing the new software update, DALK was performed using a partial-assisted femtosecond laser (partial-thickness circular cut followed by a lamellar cut) with manual intrastromal tunnel creation (partial FS-DALK group). After the software update, the femtosecond laser created the intrastromal tunnel (full FS-DALK group). RESULTS: In the full FS-DALK group, the BB's formation was significantly higher (64.3% vs. 36.4%, p = 0.04), and surgery time was shorter (21.8 ± 5.1 vs. 25.6 ± 6.8 min, p = 0.025) than in the partial FS-DALK. Penetrating keratoplasty conversion rate (7.1% vs. 15.1%, p = 0.432) was similar between the groups. Both groups showed statistically significant improvement in uncorrected and corrected distance visual acuity, central corneal thickness, surface asymmetry, and regularity indices. Endothelial cell density loss at 12 and 18 months was lower in the full compared with the partial FS-DALK group (12 months:10.0% vs. 16; 18 months: 10.7 vs. 16.5%, p < 0.001 for both comparisons). CONCLUSIONS: Creating the intrastromal guiding tunnel using FS laser for air injection resulted in a higher rate of BB formation, reduced long-term endothelial cell loss, and operating room time.


Assuntos
Transplante de Córnea , Ceratocone , Humanos , Transplante de Córnea/métodos , Córnea/cirurgia , Ceratoplastia Penetrante/métodos , Lasers , Ceratocone/diagnóstico , Ceratocone/cirurgia , Estudos Retrospectivos
8.
Int J Mol Sci ; 24(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175981

RESUMO

Citrus collections from extreme growing regions can be an important source of tolerant germplasms for the breeding of cold-tolerant varieties. However, the efficient utilization of these germplasms requires their genetic background information. Thus, efficient marker systems are necessary for the characterization and identification of valuable accessions. In this study, the efficiency of 36 SCoT markers and 60 InDel markers were evaluated as part of the broad citrus collection of the Western Caucasus. The interspecific and intraspecific genetic diversity and genetic structures were analyzed for 172 accessions, including 31 species and sets of the locally derived cultivars. Single markers, such as SCoT18 (0.84), SCoT20 (0.93), SCoT23 (0.87), SCoT31 (0.88), SCoT36 (0.87) и LG 1-4 (0.94), LG 4-3 (0.86), LG 7-11 (0.98), and LG 8-10 (0.83), showed a high discriminating power, indicating the good applicability of these markers to assess intraspecific diversity of the genus Citrus. Overall, SCoT markers showed a higher level of polymorphism than InDel markers. According to analysis of population structure, SCoT and InDel markers showed K = 9 and K = 5 genetic clusters, respectively. The lowest levels of genetic admixtures and diversity were observed among the locally derived satsumas and lemons. The highest level of genetic admixtures was observed in the lime group. Phylogenetic relationships indicated a high level of interspecific genetic diversity but a low level of intraspecific diversity in locally derived satsumas and lemons. The results provide new insight into the origin of citrus germplasms and their distribution in colder regions. Furthermore, they are important for implementing conservation measures, controlling genetic erosion, developing breeding strategies, and improving breeding efficiency.


Assuntos
Citrus , Variação Genética , Citrus/genética , Filogenia , Marcadores Genéticos , Melhoramento Vegetal
9.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834213

RESUMO

The polygenic risk score (PRS), together with the ɛ4 allele of the APOE gene (APOE-ɛ4), has shown high potential for Alzheimer's disease (AD) risk prediction. The aim of this study was to validate the model of polygenic risk in Russian patients with dementia. A microarray-based assay was developed to identify 21 markers of polygenic risk and ɛ alleles of the APOE gene. This case-control study included 348 dementia patients and 519 cognitively normal volunteers. Cerebrospinal fluid (CSF) amyloid-ß (Aß) and tau protein levels were assessed in 57 dementia patients. PRS and APOE-ɛ4 were significant genetic risk factors for dementia. Adjusted for APOE-ɛ4, individuals with PRS corresponding to the fourth quartile had an increased risk of dementia compared to the first quartile (OR 1.85; p-value 0.002). The area under the curve (AUC) was 0.559 for the PRS model only, and the inclusion of APOE-ɛ4 improved the AUC to 0.604. PRS was positively correlated with tTau and pTau181 and inversely correlated with Aß42/Aß40 ratio. Carriers of APOE-ɛ4 had higher levels of tTau and pTau181 and lower levels of Aß42 and Aß42/Aß40. The developed assay can be part of a strategy for assessing individuals for AD risk, with the purpose of assisting primary preventive interventions.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Hidrogéis , Estudos de Casos e Controles , Disfunção Cognitiva/metabolismo , Proteínas tau/genética , Proteínas tau/líquido cefalorraquidiano , Peptídeos beta-Amiloides/metabolismo , Fatores de Risco , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquidiano
10.
BMC Ophthalmol ; 21(1): 357, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625056

RESUMO

BACKGROUND: Keratoconus is a chronic degenerative disorder of the cornea characterized by thinning and cone-shaped protrusions. Although genetic factors play a key role in keratoconus development, the etiology is still under investigation. The occurrence of single-nucleotide polymorphisms (SNPs) associated with keratoconus in Russian patients is poorly studied. The purpose of this study was to validate whether three reported keratoconus-associated SNPs (rs1536482 near the COL5A1 gene, rs2721051 near the FOXO1 gene, rs1324183 near the MPDZ gene) are also actual for a Russian cohort of patients. Additionally, we investigated the COL5A1 promoter sequence for single-nucleotide variants (SNVs) in a subgroup of keratoconus patients with at least one rs1536482 minor allele (rs1536482+) to assess the role of these SNVs in keratoconus susceptibility associated with rs1536482. METHODS: This case-control study included 150 keratoconus patients and two control groups (main and additional, 205 and 474 participants, respectively). We performed PCR targeting regions flanking SNVs and the COL5A1 promoter, followed by Sanger sequencing of amplicons. The additional control group was genotyped using an SNP array. RESULTS: The minor allele frequency was significantly different between the keratoconus and control cohorts (main and combined) for rs1536482, rs2721051, and rs1324183 (p-value < 0.05). The rare variants rs1043208782 and rs569248712 were found in the COL5A1 promoter in two out of 94 rs1536482+ keratoconus patients. CONCLUSION: rs1536482, rs2721051, and rs1324183 were associated with keratoconus in a Russian cohort. SNVs in the COL5A1 promoter do not play a major role in keratoconus susceptibility associated with rs1536482.


Assuntos
Colágeno Tipo V , Ceratocone , Estudos de Casos e Controles , Colágeno Tipo V/genética , Predisposição Genética para Doença , Humanos , Ceratocone/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
11.
Int Ophthalmol ; 41(2): 639-647, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33090312

RESUMO

PURPOSE: Prediction of postoperative refraction following posterior lamellar keratoplasty is crucial for choosing proper intraocular lens power in combined surgeries. Femtosecond laser-assisted Descemet stripping endothelial keratoplasty (FS-DSEK) creates thin, planar grafts while microkeratome-assisted Descemet's stripping automated endothelial keratoplasty (DSAEK) creates non-planar, concaved grafts. We evaluated whether this fundamental difference affects the refractive outcomes in cataract surgery combined with FS-DSEK compared to cataract surgery combined with microkeratome-assisted DSAEK. METHODS: A retrospective analysis of 28 patients who underwent FS-DSEK combined with phacoemulsification and intraocular lens (IOL) implantation (group A) compared to 26 patients who underwent microkeratome-assisted DSAEK combined with phacoemulsification and IOL implantation (group B). Pre- and 1-year postoperative best-corrected visual acuity (BCVA), keratometry values, corneal thickness, central-to-peripheral graft thickness ratio (C/P ratio), and target postoperative spherical equivalent (SE) versus actual postoperative SE were analyzed. RESULTS: Target postoperative SE and actual postoperative SE significantly shifted toward hyperopia in group B, but not in group A. Postoperative hyperopic shifts were 0.14 D and 1.13 D in groups A and B, respectively (P < 0.001). BCVA improved after surgery in both groups, with no significant difference between the groups. Postoperative C/P ratio differed significantly between the groups and was negatively correlated with postoperative hyperopic shift (r = - 0.616, P < 0.001). CONCLUSION: Refractive outcomes of cataract surgery combined with FS-DSEK are relatively neutral, whereas those of cataract surgery combined with microkeratome-assisted DSAEK cause significant hyperopic shift. Clinicians should select accordingly an appropriate intraocular lens power when performing these surgeries.


Assuntos
Catarata , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Facoemulsificação , Catarata/complicações , Endotélio Corneano , Humanos , Complicações Pós-Operatórias , Refração Ocular , Estudos Retrospectivos
12.
BMC Plant Biol ; 20(Suppl 1): 350, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33050888

RESUMO

BACKGROUND: Globodera rostochiensis belongs to major potato pathogens with a sophisticated mechanism of interaction with roots of the host plants. Resistance of commercial varieties is commonly based on specific R genes introgressed from natural populations of related wild species and from native potato varieties grown in the Andean highlands. Investigation of molecular resistance mechanisms and screening the natural populations for novel R genes are important for both fundamental knowledge on plant pathogen interactions and breeding for durable resistance. Here we exploited the Solanum phureja accessions collected in South America with contrasting resistance to G. rostochiensis. RESULTS: The infestation of S. phureja with G. rostochiensis juveniles resulted in wounding stress followed by activation of cell division and tissue regeneration processes. Unlike the susceptible S. phureja genotype, the resistant accession reacted by rapid induction of variety of stress response related genes. This chain of molecular events accompanies the hypersensitive response at the juveniles' invasion sites and provides high-level resistance. Transcriptomic analysis also revealed considerable differences between the analyzed S. phureja genotypes and the reference genome. CONCLUSION: The molecular processes in plant roots associated with changes in gene expression patterns in response to G. rostochiensis infestation and establishment of either resistant or susceptible phenotypes are discussed. De novo transcriptome assembling is considered as an important tool for discovery of novel resistance traits in S. phureja accessions.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Solanum/parasitologia , Tylenchoidea/fisiologia , Animais , Ontologia Genética , Genótipo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Raízes de Plantas/imunologia , Solanum/genética , Transcriptoma
13.
BMC Plant Biol ; 17(Suppl 2): 251, 2017 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-29297325

RESUMO

BACKGROUND: The characterization of major resistance genes (R genes) in the potato remains an important task for molecular breeding. However, R genes are rapidly evolving and frequently occur in genomes as clusters with complex structures, and their precise mapping and identification are complicated and time consuming. RESULTS: Comparative analysis of root transcriptomes of Solanum phureja genotypes with contrasting resistance to Globodera rostochiensis revealed a number of differentially expressed genes. However, compiling a list of candidate R genes for further segregation analysis was hampered by their scarce annotation. Nevertheless, combination of transcriptomic analysis with data on predicted potato NBS-LRR-encoding genes considerably improved the quality of the results and provided a reasonable number of candidate genes that provide S. phureja with strong resistance to the potato golden cyst nematode. CONCLUSION: Combination of comparative analyses of tissue-specific transcriptomes in resistant and susceptible genotypes may be used as an approach for the rapid identification of candidate potato R genes for co-segregation analysis and may be used in parallel with more sophisticated studies based on genome resequencing.


Assuntos
Resistência à Doença/genética , Genes de Plantas/genética , Raízes de Plantas/metabolismo , Solanum/genética , Transcriptoma/genética , Tylenchoidea/fisiologia , Animais , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/fisiologia , Raízes de Plantas/parasitologia , Solanum/parasitologia
14.
J Antimicrob Chemother ; 72(7): 1901-1906, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28387862

RESUMO

Objectives: To study the isolates with acquired resistance to bedaquiline and linezolid that were obtained from patients enrolled in a clinical study of a novel therapy regimen for drug-resistant TB in Moscow, Russia. Methods: Linezolid resistance was detected using MGIT 960 with a critical concentration of 1 mg/L. The MIC of bedaquiline was determined using the proportion method. To identify genetic determinants of resistance, sequencing of the mmpR ( Rv0678 ), atpE , atpC , pepQ , Rv1979c , rrl , rplC and rplD loci was performed. Results: A total of 85 isolates from 27 patients with acquired resistance to linezolid and reduced susceptibility to bedaquiline (MIC ≥0.06 mg/L) were tested. Most mutations associated with a high MIC of bedaquiline were found in the mmpR gene. We identified for the first time two patients whose clinical isolates had substitutions D28N and A63V in AtpE, which had previously been found only in in vitro -selected strains. Several patients had isolates with elevated MICs of bedaquiline prior to treatment; four of them also bore mutations in mmpR , indicating the presence of some hidden factors in bedaquiline resistance acquisition. The C154R substitution in ribosomal protein L3 was the most frequent in the linezolid-resistant strains. Mutations in the 23S rRNA gene (g2294a and g2814t) associated with linezolid resistance were also found in two isolates. Heteroresistance was identified in ∼40% of samples, which reflects the complex nature of resistance acquisition. Conclusions: The introduction of novel drugs into treatment must be accompanied by continuous phenotypic susceptibility testing and the analysis of genetic determinants of resistance.


Assuntos
Antituberculosos/farmacologia , Diarilquinolinas/farmacologia , Linezolida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Acetamidas/uso terapêutico , Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Moscou/epidemiologia , Mutação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Oxazolidinonas/uso terapêutico , Estudos Prospectivos , Proteína Ribossômica L3 , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
15.
J Antimicrob Chemother ; 71(6): 1520-31, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26929267

RESUMO

BACKGROUND: Nucleic acid amplification tests are widely used in TB diagnostics. Priority tasks in their development consist of increasing the specificity and sensitivity of the detection of resistance to a wide spectrum of anti-TB drugs. METHODS: We developed a multiplexed assay allowing the detection of 116 drug resistance-determining mutations in the rpoB, katG, inhA, ahpC, gyrA, gyrB, rrs, eis and embB genes in the Mycobacterium tuberculosis complex genome and six SNPs to identify the main lineages circulating in Russia. The assay is based on the amplification of 17 fragments of the genome using the universal primer adapter technique and heat pulses at the elongation step, followed by hybridization on a microarray. RESULTS: The method was evaluated using 264 pairs of clinical samples and corresponding isolates. A significant proportion (25%) of smear-negative samples were correctly analysed by microarray analysis in addition to 96% of smear-positive samples. The sensitivity and specificity of the assay exceeded 90% for rifampicin, isoniazid, ofloxacin and second-line injection drugs. In agreement with previous studies, the specificity of ethambutol resistance was as low as 57%, while the sensitivity was 89.9%. Strong association of the Beijing lineage with a resistant phenotype was observed. Euro-American lineage strains, excluding Ural and LAM, were predominantly associated with the susceptible phenotype. CONCLUSIONS: The developed test has a high sensitivity and specificity and can be directly applied to clinical samples. The combination of mutation-based drug resistance profiling and basic genotyping could be useful for clinical microbiology studies and epidemiological surveillance of the M. tuberculosis complex.


Assuntos
Técnicas de Genotipagem/métodos , Análise em Microsséries/métodos , Testes de Sensibilidade Microbiana/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Farmacorresistência Bacteriana , Genes Bacterianos , Genótipo , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Mutação , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleotídeo Único , Federação Russa , Sensibilidade e Especificidade , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
16.
J Clin Microbiol ; 53(4): 1103-14, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25609722

RESUMO

In addition to the obligatory pathogenic species of the Mycobacterium tuberculosis complex and Mycobacterium leprae, the genus Mycobacterium also includes conditionally pathogenic species that in rare cases can lead to the development of nontuberculous mycobacterial diseases. Because tuberculosis and mycobacteriosis have similar clinical signs, the accurate identification of the causative agent in a clinical microbiology laboratory is important for diagnostic verification and appropriate treatment. This report describes a low-density hydrogel-based microarray containing oligonucleotide probes based on the species-specific sequences of the gyrB gene fragment for mycobacterial species identification. The procedure included the amplification of a 352-nucleotide fragment of the gene and its hybridization on a microarray. The triple-species-specific probe design and the algorithm for hybridization profile recognition based on the calculation of Pearson correlation coefficients, followed by the construction of a profile database, allowed for the reliable and accurate identification of mycobacterial species, including mixed-DNA samples. The assay was used to evaluate 543 clinical isolates from two regions of Russia, demonstrating its ability to detect 35 mycobacterial species, with 99.8% sensitivity and 100% specificity when using gyrB, 16S, and internal transcribed spacer (ITS) fragment sequencing as the standard. The testing of clinical samples showed that the sensitivity of the assay was 89% to 95% for smear-positive samples and 36% for smear-negative samples. The large number of identified species, the high level of sensitivity, the ability to detect mycobacteria in clinical samples, and the up-to-date profile database make the assay suitable for use in routine laboratory practice.


Assuntos
Tipagem Molecular/métodos , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/microbiologia , Mycobacterium/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase
17.
J BUON ; 20(6): 1397-406, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26854433

RESUMO

Urinary bladder cancer is a socially significant healthcare problem. A diverse array of aromatic and heterocyclic amines, derived from the chemical and transport industry, diet, and cigarette smoke are considered carcinogens for the bladder. To exert their carcinogenic effect and to initiate the carcinogenic response, the arylamines require a metabolic activation by the host enzymes to chemically reactive compounds. The aim of this article was to review the latest and basic research developments on the role of the polymorphisms in the carcinogen metabolizing enzymes N-acetyltransferase (NAT), Glutathione S-transferases (GST), and Soluble sulfotransferases (SULT), with emphasis on the susceptibility to urinary bladder cancer. A PubMed search was conducted to identify original and review articles containing information about these polymophic variants in different populations and according to their prevalence in bladder cancer patients. We noticed that some genotypes were found to be predisposing and some protective for bladder cancer development. The NAT2 slow genotype, together with GSTM1 null genotype facilitated the development of bladder cancer in almost all ethnic groups. The 213His allele of the SULT1A1 gene which is associated with lower enzyme activity and decreased mutagen activation was reported to protect from bladder cancer in almost all studies.


Assuntos
Predisposição Genética para Doença , Polimorfismo Genético , Neoplasias da Bexiga Urinária/genética , Acetiltransferases/genética , Glutationa Transferase/genética , Humanos , Risco , Sulfotransferases/genética , Neoplasias da Bexiga Urinária/etiologia
18.
J BUON ; 20(1): 180-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25778314

RESUMO

PURPOSE: The purpose of this study was to elucidate the mechanism of action of the Helix lucorum hemocyanin (HlH), b-HlH-h, and RvH2-g hemocyanins as potential agents against bladder cancer. METHODS: We evaluated the viability of 647-V, T-24, and CAL-29 bladder cancer cell lines after treatment with the tested hemocyanins. The cell viability was measured at 72 hrs with MTT and WST-1 assays. Acridine orange/propidium iodide double staining was used to discriminate between apoptotic and necrotic cells. Gene expression profiling of the 168 genes from human inflammatory cytokines and signal transduction pathways were performed on the tumor cells before and after hemocyanins' treatment. RESULTS: The results showed decreased survival of cancer cells in the presence of HlH and two functional units: b-HlH-h and RvH2-g. Acridine orange/propidium iodide double staining revealed that the decreased viability was due to apoptosis. The gene expression data showed upregulation of genes involved in the apoptosis as well as of the immune system activation, and downregulation of the CCL2, CCL17, CCL21, CXCL1, and ABCF1 genes. CONCLUSIONS: The present study is the first to report gene expression in human cells under the influence of hemocyanins. The mechanism of antitumor activity of the HlH, b-HlH-h, and RvH2-g hemocyanins includes induction of apoptosis. In addition to the antiproliferative effect, downregulation of the genes with metastatic potential was observed. Together with the already known immunogenic effect, these findings support further studies on hemocyanins as potential therapeutic agents against bladder cancer.


Assuntos
Antineoplásicos/farmacologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hemocianinas/farmacologia , Caramujos/química , Neoplasias da Bexiga Urinária/genética , Animais , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Hemocianinas/isolamento & purificação , Humanos , Necrose , Análise de Sequência com Séries de Oligonucleotídeos , Fatores de Tempo , Neoplasias da Bexiga Urinária/patologia
19.
Mol Cell Biochem ; 396(1-2): 79-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25064448

RESUMO

Under some pathological conditions, the natural dicarbonyl compounds can accumulate in the blood. The examples are malonyldialdehyde (MDA) formed as a secondary product of lipid peroxidation of unsaturated fatty acids during atherosclerosis, and glyoxal (GOX), a homolog of MDA, which accumulates during glucose autoxidation in patients with diabetes mellitus. This study compared the influence of both dicarbonyl compounds on low-density lipoproteins (LDL) and the membrane of endotheliocytes. In comparison with GOX, MDA induced more pronounced changes in physical and chemical properties of LDL particles. On the other hand, GOX-modified LDL particles were more prone to oxidation and aggregation than MDA-modified LDL. Incubation of endotheliocytes with MDA increased cell mechanical stiffness in contrast to incubation with GOX, which decreased it.


Assuntos
Células Endoteliais/efeitos dos fármacos , Glioxal/farmacologia , Lipoproteínas LDL/química , Malondialdeído/farmacologia , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Eletroforese em Gel de Ágar , Células Endoteliais/química , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Glioxal/química , Humanos , Peróxidos Lipídicos/química , Lipoproteínas LDL/sangue , Malondialdeído/química , Reologia/métodos
20.
Z Naturforsch C J Biosci ; 69(7-8): 325-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25265853

RESUMO

As an extension of our studies on the antitumour properties of various hemocyanins, we sought to compare the antiproliferative effects of hemocyanins derived from two snail species: Helix lucorum (HIH) and Helix aspersa (HaH). This is the first report on the antitumour effects of HaH. We hypothesized that HaH has antitumour effects not only against bladder cancer, as previously shown with other hemocyanins, but also on other cancer cell lines. The antiproliferative properties of the mentioned hemocyanins were investigated in vitro on the following human cell lines: bladder cancer (CAL-29 and T-24), ovarian cancer (FraWü), acute monocytic leukemia (THP-1), prostate cancer (DU-145), glioma cancer (LN-18), and Burkitt's lymphoma (Daudi). The properties of HaH were compared to those of HlH, keyhole limpet hemocyanin (KLH), and two positive controls (doxorubicin and mitomycin C). An antiproliferative effect of the total molecule and one structural subunit of HaH, betac-HaH, against both bladder cancer cell lines, T-24 and CAL-29, was observed. The cytotoxic effect of HaH ranged between 15% and 60% among the other tested cell lines. The endotoxin contamination did not affect the efficacy of HaH. Therefore, HlH and HaH could be appropriate for more detailed investigations of their use as antitumour agents for the studied cancers.


Assuntos
Proliferação de Células/efeitos dos fármacos , Caracois Helix/química , Hemocianinas/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Transmissão
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