Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Mikrobiyol Bul ; 53(2): 156-169, 2019 Apr.
Artículo en Turco | MEDLINE | ID: mdl-31130120

RESUMEN

HBV is a DNA virus and the causative agent of hepatitis B infection. Hepatitis B is a contagious disease and is still a major health problem all over the world. When the infection become chronic, it may cause serious diseases such as fibrosis, cirrhosis and/or hepatocellular carcinoma. Interferon/pegylated interferon by intravenous route and nucleoside/nucleotide (NA) analogues such as lamivudine, adefovir, entecavir, telbivudine and tenofovir given by oral route are used in the treatment. Antivirals given by oral route are mostly preferred in the treatment. However, because of the replication strategy and biological properties of HBV, mutations that cause antiviral resistance against these drugs can occur at different rates, although they can vary from drug to drug over time. It is possible that drug resistant virus may transmit from patient to healthy individuals. Therefore, there is a possibility of infection with drug-resistant HBV before treatment. Antiviral resistance mutations are divided into four categories; i) Nucleos(t)ide analog resistance (NAr)-related mutations, ii) primary drug resistance mutations, iii) secondary/compensatory mutations, iv) putative antiviral resistance mutations and pre-treatment variations. Recent studies have focused particularly on putative mutations and pre-treatment variations. The aim of this study was to better understanding of the antiviral resistance profiles of chronic hepatitis B (CHB) patients treated and untreated with NA, and help to prevent unnecessary drug use, minimize the side effects and economic damages. A total of 124 patients who have received nucleoside analog (NA) drug treatments (n= 72) and patients without NA treatment (n= 52) were included in the study. Viral DNA was isolated from the plasma samples of the patients. A DNA fragment, which is 551 bp, was amplified and sequenced including the binding side of all nucleoside analogs containing the B, C and D domains located in the reverse transcriptase region in the HBV genome. Different types of mutations were detected in 13 (18.05%) of 72 treated patients and in 18 (34.61%) of 52 untreated patients (p< 0.05). Primary drug resistance mutations such as rtI169T, rtA181T/V, rtT184A/C/F/G/I/L/M/S, rtA194T, rtS202C/G/I, rtM204I/V/S, rtN236T, rt M250I/L/V and rtV173L were not detected in any of the patient samples. However, potential drug resistance mutations such as rtR164R, rtG165D/A, rtG172Q, rtS176N, rtF178V, rtA181G, rtS185N/G/C, rtV207M, rtQ215H/S, rtL231V, rtI233K, rtN238S, rtV253T, rtC256G/S and rtI266R/V were detected in untreated patient samples in B, C, D and D domains of reverse transcriptase region. Our results have suggested that the detection of pretreatment variations could be helpful for choosing the correct antiviral drug for the better treatment management.


Asunto(s)
Farmacorresistencia Viral , Virus de la Hepatitis B , Hepatitis B Crónica , Antivirales/farmacología , Farmacorresistencia Viral/genética , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Humanos , Mutación , Inhibidores de la Transcriptasa Inversa/farmacología
2.
Mycopathologia ; 183(4): 701-708, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29725811

RESUMEN

Candida parapsilosis sensu stricto is an emerging cause of hospital-acquired Candida infections, predominantly in southern Europe, South America, and Asia. We investigated the genetic diversity and antifungal susceptibility profile of 170 independent C. parapsilosis sensu stricto strains obtained from patients with candidemia who were treated at the Ege University Hospital in Izmir, Turkey, between 2006 and 2014. The identity of each strain was confirmed via PCR amplification and digestion of the secondary alcohol dehydrogenase-encoding gene. The 24-h geometric mean minimum inhibitory concentrations of the antifungal agents, in increasing order, were as follows: posaconazole, 0.10 µg/mL; voriconazole, 0.21 µg/mL; caspofungin, 0.38 µg/mL; amphotericin B, 0.61 µg/mL; anidulafungin, 0.68 µg/mL; and fluconazole, 2.95 µg/mL. Microsatellite genotyping of the isolates (using fluorescently labeled primers and a panel of four different short-nucleotide repeat fragments) identified 25, 17, 17, and 8 different allelic genotypes at the CP6, B5, CP4, and CP1 locus, respectively. Posaconazole, caspofungin, and amphotericin B showed the greatest in vitro activity of the tested systemic azole, echinocandin, and polyene agents, respectively, and the observed antifungal susceptibility of the isolates was shown to be independent of their isolation source. We obtained a combined discriminatory power of 0.99 with a total of 130 genotypes for 170 isolates tested. Finally, microsatellite profiling analysis confirmed the presence of identical genotype between separate isolates, supporting that effective surveillance and infection-prevention programs are essential to limit the impact of C. parapsilosis sensu stricto on hospitalized patients' health.


Asunto(s)
Candida parapsilosis/clasificación , Candida parapsilosis/efectos de los fármacos , Candidemia/microbiología , Farmacorresistencia Fúngica , Variación Genética , Alcohol Deshidrogenasa/genética , Antifúngicos/farmacología , Candida parapsilosis/genética , Candida parapsilosis/aislamiento & purificación , Proteínas Fúngicas/genética , Genotipo , Hospitales Universitarios , Humanos , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa , Turquía
3.
Ann Hum Biol ; 45(6-8): 506-515, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30616447

RESUMEN

BACKGROUND: Rapidly mutating (RM) Y-STRs recently emerged as a useful genotyping tool that can counteract problems normally associated with traditional Y-STRs. For instance, RM Y-STRs have the potential to differentiate Y-chromosomes from both close and distant paternal relatives. AIM: Characterisation of 13 RM Y-STR loci in a new sample pool from Turkey in terms of population genetic data and mutation rates. SUBJECTS AND METHODS: One hundred father-son pairs from South and East Turkey were genotyped. Based on the 99 father haplotypes unique to the current study, statistical parameters of forensic interest were computed. Nei's DA distances among 112 global population datasets were estimated and visualised by phylogenetic and multidimensional scaling (MDS) analyses. RESULTS: Fifteen father-son pairs were found to differ at a single locus and four at two loci, resulting in a differentiation rate of 19%. Mutations were observed at 10 out of 13 loci, with rates ranging from 1 × 10-2 to 6 × 10-2. CONCLUSION: Mutation rates and differentiation rates between the father-son pairs were similar to those from the literature. In contrast to previous work, novel phylogenetic tree construction results based on Nei's DA distances suggested a close correlation between the geographic and genetic distances observed, except for known cases of past mass migration events.


Asunto(s)
Cromosomas Humanos Y/genética , Repeticiones de Microsatélite/genética , Mutación , Padre , Humanos , Masculino , Tasa de Mutación , Turquía
4.
Forensic Sci Int Genet ; 24: 176-179, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27479879

RESUMEN

Despite its large geographic and population size only little is known about the mitochondrial (mt)DNA make up of Turkey.orensically relevant data are almost completely absent in the literature. We analyzed the mtDNA control region of 224 volunteers from South Eastern Turkey and compared the data to populations from neighboring countries. The haplotypes will be made available via the EMPOP database (EMP00670) and contribute to the body of forensic mtDNA data.


Asunto(s)
ADN Mitocondrial/genética , Genética de Población , Haplotipos , Bases de Datos de Ácidos Nucleicos , Humanos , Análisis de Secuencia de ADN , Turquía
5.
Mycopathologia ; 175(3-4): 287-94, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23546773

RESUMEN

Recent studies have clearly defined the vaginopathic Candida albicans strains that cause severe vulvovaginal candidiasis (VVC). Therefore, genotyping C. albicans isolates may predict the success of and assist in choosing the appropriate antifungal therapy. The purpose of this study was to compare the genotypes of C. albicans isolates causing VVC with those found in asymptomatic healthy pregnant and non-pregnant women in Adana, Turkey, as well as the antifungal susceptibility profiles of these isolates. A total of 216 independent C. albicans isolates were genotyped by allelic combination based on the microsatellite marker analysis of one such microsatellite, present in the promoter region of the elongation factor 3-encoding gene (CEF3) of C. albicans. The susceptibility testing profiles of all of the isolates against five antifungals and boric acid were obtained retrospectively from our laboratory records. We identified 20 genotypes on the basis of different allelic combinations at the CEF3 locus with a discriminatory power of 0.85. Genotypes 136-144 and 126-135 were present in 50 % of the isolates. No differences existed in the genotypic profiles of fungal isolates between pregnant and non-pregnant women. Remarkably, we did not find a single vaginopathic genotype. All of the isolates were susceptible to amphotericin B and 5-fluorocytosine, and the fluconazole and ketoconazole resistance rates were 0.9 and 3.7 %, respectively. Therefore, we did not find any correlation between genotype, severity of VVC, and antifungal resistance (P > 0.05). Even so, additional molecular data may provide new insights into the management of VVC.


Asunto(s)
Candida albicans/clasificación , Candida albicans/genética , Candidiasis Vulvovaginal/microbiología , Candidiasis Vulvovaginal/patología , Tipificación Molecular , Técnicas de Tipificación Micológica , Antifúngicos/farmacología , Candida albicans/aislamiento & purificación , Candida albicans/patogenicidad , Candidiasis Vulvovaginal/epidemiología , ADN de Hongos/genética , Femenino , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite , Embarazo , Turquía/epidemiología
6.
Mikrobiyol Bul ; 47(1): 109-21, 2013 Jan.
Artículo en Turco | MEDLINE | ID: mdl-23390908

RESUMEN

Vulvovaginal candidosis is the second most common cause of vaginitis (17-39%) after bacterial vaginosis (22-50%). Since the diagnosis of vulvovaginal candidosis mainly depends on clinical findings without mycologic confirmatory tests and treated empirically, the actual incidence rate of vulvovaginal candidosis is unknown. Approximately 70-90% of vulvovaginal candidosis cases are caused by Candida albicans, however the increasing incidence of C.glabrata infections and its reduced susceptibility to azole drug therapy have generated increasing attention. The epidemiology and population structure of vulvovaginal candidosis due to C.glabrata are poorly characterized. This study was aimed to genotype the C.glabrata strains isolated from vaginal samples in Cukurova region, Turkey by microsatellite markers, to investigate the antifungal susceptibility profiles of the strains and to determine the molecular mechanisms leading to phenotypical azole resistance. A total of 34 unrelated vaginal C.glabrata strains isolated from patients with acute (n= 11) and recurrent (n= 14) vulvovaginal candidosis, control group (n= 9) without vaginitis symptoms, and a reference strain of C.glabrata CBS 138 (ATCC 2001) were included in the study. These isolates were genotyped using multiple-locus variable number tandem repeat analysis of three microsatellite markers (RPM2, MTI, and Cg6). Analysis of microsatellite markers was performed by fragment size determination of RPM2, MTI, and Cg6 PCR products through capillary electrophoresis. For each of the evaluated strains, DNA sequence analysis was performed for one gene (CgERG11) and four loci (CgPDR1, NTM1, TRP1, and URA3) to detect mutations possibly associated with antifungal resistance in each strain. In vitro susceptibility profiles of the strains to 13 antifungals and boric acid were determined according to CLSI document M27-A3 to investigate possible relationships between detected mutations and phenotypic resistance. C.glabrata CBS 138 strain was found to be susceptible to all the antifungals tested, while one of (%2.9) 34 vaginal C.glabrata isolates was found to be dose-dependent susceptible to fluconazole, 13 (38.2%) to itraconazole and 3 (8.8%) to voriconazole. No resistant strain were detected in the study population. Only three isolates were found to be resistant to clotrimazole (8.8%), however no relationship was identified between the genotypes and phenotypic resistance (p> 0.05). Thirteen genotypes were detected by microsatellite marker analysis, with high discrimination power (DP= 0.877). As a result, microsatellite marker analysis was validated as a rapid, reliable method for genotyping C.glabrata strains with good, but not optimal discriminatory power. Further studies examining larger numbers of isolates are needed to verify possible relationships between mutations and phenotypic resistance.


Asunto(s)
Candida glabrata , Genotipo , Antifúngicos/farmacología , Candida/aislamiento & purificación , Farmacorresistencia Fúngica , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite , Mutación , Análisis de Secuencia de ADN
7.
Asian J Psychiatr ; 5(2): 169-74, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22813662

RESUMEN

Cytogenetic analysis is an important stage in understanding the genetic background of manic depression (MD), and may provide a valuable clue to the identification of target loci and successful search for major genes. In order to identify chromosomal regions we aimed to detect the relationships between chromosomal aberrations (CAs) and immunological markers in a family with MD and psoriasis. We used the cell cultivation and conventional G-banding. We found predominantly numerical aberrations. The most common aneuploidy was chromosome 8, followed by chromosome 22, 21, 15, X and Y. However, structural aberrations consisted of duplications, deletions, translocations and breaks, with a focus on: loci on del(1)(q12-q23), del(1)(q21.1-q24), del(1)(q21.1-q23), del(10)(p11.2-pter), der(2)t(2;4)(p25;p12), t(2;22)(p14;p13), t(19;Y)? and dup(10)(q26). The susceptibility genes of MD or psoriasis may be located on these loci. Numerical sex CAs included 4(5.8%) with 45,X, 3(4.3%) with 47,XXY, and 4(5.8%) with structural chromosome X; del(X)(q13); del(X)(p11-pter) del(X)(q21.3) and inv(Y)(q11.2). We also conducted an immunological study. According results of this study, the percentage of CD2+, CD4+ and CD8+ lymphocytes of the father were significantly higher, whereas CD4+ lymphocytes were decreased in the mother, when compared the healthy persons. The percentage of CD4 level of the son was decreased, whereas CD8+ lymphocytes were higher. The CD4/CD8 ratio of the father and the son was found to be significantly high. These results may suggest that MD and psoriasis have a significant impact on both genetic and immunological parameters.


Asunto(s)
Aneuploidia , Trastorno Bipolar/genética , Predisposición Genética a la Enfermedad/genética , Psoriasis/genética , Adulto , Biomarcadores/sangre , Trastorno Bipolar/inmunología , Femenino , Marcadores Genéticos/genética , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Linaje , Psoriasis/inmunología
8.
Croat Med J ; 52(6): 703-8, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22180269

RESUMEN

AIM: To investigate the distribution of 17 Y-short tandem repeat (STR) loci in the population of the Cukurova region of Turkey. METHODS: In the period between 2009 and 2010, we investigated the distribution of 17 Y-STRs in a sample of 249 unrelated healthy men from the Cukurova region of Turkey. Genomic DNA was extracted with InstaGene matrix and Y-STRs were determined using the AmpFISTR Yfiler PCR amplification kit. Gene and haplotype diversity values were estimated using the Arlequin software. To compare our data to other populations, population pairwise genetic distances and associated probability values were calculated using the Y Chromosome Haplotype Reference Database Web site software. RESULTS: At 17 Y-STR loci we detected 148 alleles. The lowest gene diversity in this region was 0.51 for DYS391 and the highest 0.95 for DYS385a/b. Haplotype diversity was 0.9997±0.0004. We compared our data with haplotype data of other Turkish populations and no significant differences were found, except with Ankara population (Φst=0.025, P=0.018). Comparisons were also made with the neighboring populations using analysis of molecular variance of the Y-STR loci genetic structure and our population was nearest to Lenkoran-Azerbaijani (Φst=0.012, P=0.068) and Iranian Ahvaz population (Φst=0.007, P=0.173), followed by Greek (Φst=0.025, P=0.000) and Russian (Φst=0.048, P=0.000) population. Other countries like Portugal, Spain, Italy, Egypt, Israel (Palestinian Authority Area), and Taiwan showed a high genetic distance from our population. CONCLUSION: Our study showed that Y-STR polymorphisms were a powerful discrimination tool for routine forensic applications and could be used in genealogical investigations.


Asunto(s)
Cromosomas Humanos Y/genética , Frecuencia de los Genes/genética , Haplotipos/genética , Repeticiones de Microsatélite/genética , Alelos , Variación Genética/genética , Humanos , Masculino , Polimorfismo Genético/genética , Turquía/epidemiología
9.
J Clin Endocrinol Metab ; 94(10): 3633-3639, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19755480

RESUMEN

CONTEXT: The neurokinin B (NKB) receptor, encoded by TACR3, is widely expressed within the central nervous system, including hypothalamic nuclei involved in regulating GnRH release. We have recently reported two mutations in transmembrane segments of the receptor and a missense mutation in NKB in patients with normosmic isolated hypogonadotropic hypogonadism (nIHH). PATIENTS AND METHODS: We sequenced the TACR3 gene in a family in which three siblings had nIHH. The novel mutant receptor thus identified was studied in a heterologous expression system using calcium flux as the functional readout. RESULTS: All affected siblings were homozygous for the His148Leu mutation, in the first extracellular loop of the NKB receptor. The His148Leu mutant receptor exhibited profoundly impaired signaling in response to NKB (EC(50) = 3 +/- 0.1 nm and >5 microm for wild-type and His148Leu, respectively). The location of the mutation in an extracellular part of the receptor led us also to test whether senktide, a synthetic NKB analog, may retain ability to stimulate the mutant receptor. However, the signaling activity of the His148Leu receptor in response to senktide was also severely impaired (EC(50) = 1 +/- 1 nm for wild-type and no significant response of His148Leu to 10 microm). CONCLUSIONS: Homozygosity for the TACR3 His148Leu mutation leads to failure of sexual maturation in humans, whereas signaling by the mutant receptor in vitro in response to either NKB or senktide is severely impaired. These observations further strengthen the link between NKB, the NKB receptor, and regulation of human reproductive function.


Asunto(s)
Amenorrea/genética , Hipogonadismo/genética , Mutación Missense , Neuroquinina B/análogos & derivados , Fragmentos de Péptidos/uso terapéutico , Receptores de Neuroquinina-3/genética , Sustancia P/análogos & derivados , Adolescente , Adulto , Mama/anomalías , Análisis Mutacional de ADN , Femenino , Histidina , Homocigoto , Hormonas/sangre , Humanos , Hipogonadismo/sangre , Leucina , Masculino , Neuroquinina B/genética , Linaje , Fragmentos de Péptidos/farmacología , Pubertad/sangre , Pubertad/genética , Hermanos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Sustancia P/farmacología , Sustancia P/uso terapéutico
10.
Nat Genet ; 41(3): 354-358, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19079066

RESUMEN

The timely secretion of gonadal sex steroids is essential for the initiation of puberty, the postpubertal maintenance of secondary sexual characteristics and the normal perinatal development of male external genitalia. Normal gonadal steroid production requires the actions of the pituitary-derived gonadotropins, luteinizing hormone and follicle-stimulating hormone. We report four human pedigrees with severe congenital gonadotropin deficiency and pubertal failure in which all affected individuals are homozygous for loss-of-function mutations in TAC3 (encoding Neurokinin B) or its receptor TACR3 (encoding NK3R). Neurokinin B, a member of the substance P-related tachykinin family, is known to be highly expressed in hypothalamic neurons that also express kisspeptin, a recently identified regulator of gonadotropin-releasing hormone secretion. These findings implicate Neurokinin B as a critical central regulator of human gonadal function and suggest new approaches to the pharmacological control of human reproduction and sex hormone-related diseases.


Asunto(s)
Hipogonadismo/genética , Neuroquinina B/genética , Neuroquinina B/fisiología , Receptores de Neuroquinina-3/genética , Reproducción/genética , Secuencia de Aminoácidos , Cromosomas Humanos Par 4 , Análisis Mutacional de ADN , Familia , Gónadas/metabolismo , Gónadas/fisiología , Humanos , Kisspeptinas , Modelos Biológicos , Mutación/fisiología , Neuroquinina B/metabolismo , Neuronas/metabolismo , Linaje , Receptores de Neuroquinina-3/metabolismo , Reproducción/fisiología , Homología de Secuencia de Aminoácido , Proteínas Supresoras de Tumor/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA