RESUMO
AIM: Ventricular extrasystole (PVC) is characterized by premature ventricular depolarization and is associated with increased risk of arrhythmias and structural heart disease. This study aimed to investigate the association between the PVC burden and left atrial (LA) function in individuals without known cardiac disease. MATERIAL AND METHODS: A cross-sectional study was conducted on 102 patients with PVCs who were admitted to a cardiology clinic. Transthoracic echocardiography was used to assess left ventricle (LV) parameters, including LV mass, LV ejection fraction (LVEF), LV global longitudinal strain (LVGLS), and LA function was evaluated using strain imaging. The PVC burden was categorized into three groups: <10 %, 10-20 %, and >20 %. RESULTS: Changes in LV dimensions and LV mass index were associated with the groups with the PVC burden with 10-20 %, and >20 %. but differences in LVEF and LVGSL were not significant. Mean E / e' increased as the PVC burden increased (p<0.001). The mean global LA peak strain decreased as the PVC burden increased (p<0.001), while other mean LA measurements increased as the PVC burden increased (p<0.001) A higher PVC burden was associated with impaired LA function, as indicated by decreased global LA peak strain (PVC burden <10 %=38.1±3.2 vs. PVC burden 10-20 %=32.4±3.2 vs. PVC burden >20 %=27.7±2.6, in all groups p<0.001) and with increased LA stiffness (PVC burden <10 %=18.6±3.2 vs. PVC burden 10-20 %=27.5±5.5 vs. PVC burden >20 %=39.0±7.9, in all groups p<0.001). A strong negative correlation was found between global LA peak strain and LA stiffness (r=-0.779, p<0.001). CONCLUSION: In individuals without known cardiac disease, a higher PVC burden was associated with impaired LA function, indicated by increased E / e', decreased LA strain, and increased LA stiffness. These findings suggest that PVC burden may contribute to LA dysfunction, potentially increasing the risk of cardiovascular events.
Assuntos
Fibrilação Atrial , Cardiopatias , Disfunção Ventricular Esquerda , Complexos Ventriculares Prematuros , Humanos , Ventrículos do Coração/diagnóstico por imagem , Fibrilação Atrial/complicações , Estudos Transversais , Função Ventricular Esquerda , Volume Sistólico , Cardiopatias/complicações , Complexos Ventriculares Prematuros/complicações , Complexos Ventriculares Prematuros/diagnóstico , Átrios do Coração/diagnóstico por imagemRESUMO
OBJECTIVE: Clinical studies detecting the increase in thrombotic events with vitamin D deficiency note the relationship between vitamin D and thrombosis. This study aims at evaluating the relationship between serum vitamin D levels and coronary thrombus burden. PATIENTS AND METHODS: We retrospectively evaluated 77 patients with ST-elevated myocardial infarction (STEMI). Serum vitamin D levels, degree of coronary thrombus, Thrombolysis in Myocardial Infarction (TIMI) frame count and the extent and severity of atherosclerosis in coronary arteries were also measured in all cases. Patients were divided into 2 groups, according to thrombus load. RESULTS: The rate of vitamin D deficiency in the study population was 79.22% (< 20 ng/mL). Vitamin D levels were significantly higher in patients with a mild thrombus load than in patients with a severe thrombus load (16 vs. 13.95 p = 0.018). Gensini scores were significantly higher in patients with a severe thrombus burden than in patients with a mild thrombus burden (42 vs. 54.5 p = 0.014). There was a low negative correlation between vitamin D levels and thrombus burden classification grades (r = -0.304, p = 0.007), Cx TIMI frame counts (r = -0.402, p < 0.001), and RCA TIMI frame counts (r = -0.479, p < 0.001). There was a moderate negative correlation between serum vitamin D levels and LAD TIMI frame count (r = -0.507, p < 0.001). CONCLUSIONS: The results of our study showed that low 25(OH)D3 levels are an independent predictor of high coronary artery thrombus load and post-procedural TIMI frame count increase in patients with STEMI undergoing primary percutaneous coronary intervention.
Assuntos
Trombose Coronária , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Trombose , Deficiência de Vitamina D , Humanos , Estudos Retrospectivos , Intervenção Coronária Percutânea/métodos , Deficiência de Vitamina D/complicações , Vitamina D , Angiografia Coronária/métodosRESUMO
BACKGROUND: There is limited data about ICU, short and long-term mortality prediction of severe CAP with neutrophil-to-lymphocyte ratio (NLR): N-terminal proB- type natriuretic peptide (NT-proBNP): C-reactive protein (CRP). AIM: Besides the known severity indexes of ICU, can NLR, NT-proBNP, CRP predict ICU, short and long term mortality? METHODS: A retrospective cohort study was carried out in a level III ICU of a tertiary training hospital for chest diseases and thoracic surgery. RESULTS: Over the study period, a total of 143 patients were enrolled in the study. The APACHE II scoring showed a significantly higher predicting performance for ICU mortality (p = 0.002). The performance for predicting short term mortality NLR (p = 0.039) and long term mortality NTproBNP (p = 0.002) had a significantly higher performance. The survival analysis revealed that mortality was significantly higher in patients with CURB65 score ≥ 4 (p = 0.047). CONCLUSION: NLR, NTproBNP > 2000pg/mL can be used to predict pneumonia severity in ICU alike CURB65 and PSI. Higher NLR, APACHE II and atrial fibrillation can cause an important mortality factor in long term. Consequently, clinicians should take an attention for good cardiac evaluation and cardiac follow-up of patients with CAP (Tab. 4, Fig. 3, Ref. 36).
Assuntos
Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Mortalidade Hospitalar , Contagem de Leucócitos , Linfócitos/imunologia , Peptídeo Natriurético Encefálico/sangue , Neutrófilos/imunologia , Pneumonia/imunologia , Pneumonia/mortalidade , Insuficiência Respiratória/imunologia , Insuficiência Respiratória/mortalidade , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Análise de Sobrevida , TurquiaRESUMO
AIM: Information regarding the Neutrophil/Lymphocyte ratio (NLR) in sarcoidosis and the data from studies recommending its use as an indicator of inflammation and in the differential diagnosis and prognosis, are limited. With this study, it was aimed to obtain data regarding the NLR level in the patients at the time of presentation to the hospital and to determine the characteristics of patients in whom the NLR value was > 2. RESULTS: During the study period, of the 3434 patients with the sub-diagnosis of D86, 1300 cases whose complete blood count values had been recorded at the time of presentation were included in the study. Of the cases, 40 % were pulmonary sarcoidosis, 7 % were pulmonary sarcoidosis with sarcoidosis of the lymph nodes, 8 % were lymph node sarcoidosis, 1 % were sarcoidosis, of other combined areas, and 40 % of the cases were sarcoidosis that were unspecified. The F/M of the cases were 947/353, and the average age of the cases was 44. When the sarcoidosis groups were grouped into NLR < 2 (Group 1) and NLR ≥ 2 (Gorup 2), 27â % were Group 1, 73 % were Group 2, and a significant correlation was found between the two groups. When the inflammatory indicators were compared with NLR, the PLT/MPV was found to be statistically insignificant, and the ACE, ESR and CRP were found to be statistically significant. CONCLUSION: The Neutrophil/Lymphocyte ratio in the complete blood count, which is an easy and cheap test, can be used as an indicator of inflammation in Sarcoidosis. In clinical practice, wide-based studies comprising the activity and the staging in the prognosis of sarcoidosis are required (Tab. 2, Fig. 2, Ref. 26).
Assuntos
Linfócitos , Neutrófilos , Sarcoidose/imunologia , Adulto , Contagem de Células Sanguíneas , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sarcoidose/sangueRESUMO
OBJECTIVE: The aim of this study was to evaluate the clinical performance of a glass ionomer restorative system compared with a microfilled hybrid posterior composite in a four-year randomized clinical trial. METHODS: A total of 140 (80 Class 1 and 60 Class 2) lesions in 59 patients were either restored with a glass ionomer restorative system (Equia, GC, Tokyo, Japan), which was a combination of a packable glass ionomer (Equia Fil, GC) and a self-adhesive nanofilled coating (Equia Coat, GC), or with a microfilled hybrid composite (Gradia Direct Posterior, GC) in combination with a self-etch adhesive (G-Bond, GC) by two experienced operators according to the manufacturer's instructions. Two independent examiners evaluated the restorations at baseline and at one, two, three, and four years postrestoration according to the modified US Public Health Service criteria. Polyvinyl siloxane impression negative replicas at each recall were observed under scanning electron microscopy (SEM) to evaluate surface characteristics. The statistical analyses were carried out with McNemar, Pearson Chi-square, and Cochran Q-tests (p<0.05). RESULTS: After four years, 126 (76 Class 1 and 50 Class 2) restorations were evaluated in 52 patients, with a recall rate of 88.1%. None of the restorations showed trends to downgrade in anatomical form, secondary caries, surface texture, postoperative sensitivity, and color match (p>0.05). Significant differences in marginal adaptation and discoloration were found at four years compared to baseline for both restorative materials for Class 1 and Class 2 restorations (p<0.05). Only one Class 2 Equia restoration was missing at three years (3.9%), and another one was missing at four years (7.7%) (p>0.05). SEM evaluations were in accordance with the clinical findings. CONCLUSIONS: The use of both materials for the restoration of posterior teeth exhibited a similar and clinically successful performance after four years.
Assuntos
Resinas Acrílicas/uso terapêutico , Resinas Compostas/uso terapêutico , Cárie Dentária/cirurgia , Restauração Dentária Permanente/métodos , Dióxido de Silício/uso terapêutico , Adolescente , Adulto , Adaptação Marginal Dentária , Humanos , Resultado do Tratamento , Adulto JovemRESUMO
The 4q deletion syndrome is a rare chromosome deletion syndrome with a wide range of clinical phenotypes. Herein we report cases of twins (karyotype 46, XY) carrying terminal deletion of the chromosome 4 (q31qter) segment resulting in craniofacial dysmorphism, skeletal anomalies, ocular findings and cardiac defect.
Assuntos
Anormalidades Múltiplas/genética , Transtornos Cromossômicos/genética , Doenças em Gêmeos/genética , Deleção Cromossômica , Transtornos Cromossômicos/patologia , Transtornos Cromossômicos/fisiopatologia , Cromossomos Humanos Par 4/genética , Idade Gestacional , Humanos , Recém-Nascido , Masculino , TurquiaRESUMO
Mitochondrial DNA (mtDNA) mutations have been implied in many diseases including cancer and inflammatory diseases. The aim of this study is to investigate the relationship between the 4977 bp deletion of the mtDNA and chronic cervicitis or cervix cancer in patients. The study included a group of patients with chronic cervicitis or cervix cancer, and a control group consisting of individuals without any cervical tissue disease. A total of 72 subjects in an East Turkish population were included in the study. Of these, 35 had chronic cervicitis, 21 had cervix cancer and 16 served as the control group. Isolation of mtDNA was performed from the tissues of these patients and then mtDNA deletions were studied using polymerase chain reaction (PCR). In the cancer groups, there were 9.5% heteroplasmic and homoplasmic deletions. There were no homoplasmic deletions in the cervicitis and control groups, but the frequencies of heteroplasmic deletions were 80.0 and 31.2%, respectively. Chronic inflammation leading to increased reactive oxygen species (ROS) may be the cause of the high mtDNA 4977 bp deletion frequencies in cancer and cervicitis. The older age of the cancer patient may suggest that ageing in addition to long time exposure to ROS may lead to deletions and subsequently cancer. This is the first study to investigate the relationship of the mtDNA 4977 bp deletion to chronic cervicitis and cervix cancer.
Assuntos
Anormalidades Múltiplas/genética , Transtornos do Desenvolvimento Sexual/genética , Hipotireoidismo/genética , Anormalidades Múltiplas/diagnóstico , Cromossomos Humanos Par 13/genética , Pé Torto Equinovaro/genética , Fácies , Retardo do Crescimento Fetal/genética , Humanos , Hidrocefalia/genética , Hipotireoidismo/tratamento farmacológico , Recém-Nascido , Masculino , Cromossomos em Anel , Síndrome , Tiroxina/uso terapêuticoRESUMO
PURPOSE: To determine the change in the chemical composition of enamel and dentin as well as to evaluate the differences in surface texture of the same dental hard tissues following three at-home bleaching systems in vitro. METHODS: Sixty extracted intact human anterior teeth were used in this study. Thirty teeth were used as samples for enamel, and the buccal surfaces of the remaining 30 teeth were abraded and used as dentin samples. Prior to bleaching treatments, calcium (Ca), phosphorus (P), potassium (K), sodium (Na), magnesium (Mg), fluoride (F), and oxygen (O) levels of each sample were measured using an energy dispersive spectrometer. The teeth were then randomly allocated into three groups according to the bleaching system used, as follows: GI, 10% carbamide peroxide (CP); GII, 20% CP; GIII, and 35% CP. Following the bleaching treatments, Ca, P, K, Na, Mg, F, and O measurements were repeated. The surface configurations were examined using scanning electron microscopy (SEM). The data were analyzed using Wilcoxon signed rank and Kruskal-Wallis tests followed by the Dunn test. RESULTS: All three bleaching systems tested caused similar changes in the chemical composition of enamel and dentin. Bleaching systems decreased Ca and K, while F and O levels increased in enamel. In dentin, Ca, P, and K levels decreased; however, Na, F, and O levels increased. SEM observations revealed no deleterious effect on enamel and dentin. CONCLUSION: The use of home bleaching agents could affect the chemical composition of dental hard tissues, whereas the change in the chemical composition of enamel and dentin was not affected by the CP concentration of the bleaching systems used.
Assuntos
Esmalte Dentário/química , Dentina/química , Peróxidos/administração & dosagem , Clareadores Dentários/administração & dosagem , Clareamento Dental/métodos , Ureia/análogos & derivados , Cálcio/análise , Peróxido de Carbamida , Esmalte Dentário/ultraestrutura , Dentina/ultraestrutura , Fluoretos/análise , Humanos , Umidade , Magnésio/análise , Teste de Materiais , Microscopia Eletrônica de Varredura , Oxigênio/análise , Fósforo/análise , Potássio/análise , Sódio/análise , Espectrometria por Raios X , Temperatura , Fatores de Tempo , Ureia/administração & dosagem , Água/químicaRESUMO
Despite their monophyletic origin, mitochondrial (mt) genomes of plants and animals have developed contrasted evolutionary paths over time. Animal mt genomes are generally small, compact, and exhibit high mutation rates, whereas plant mt genomes exhibit low mutation rates, little compactness, larger sizes, and highly rearranged structures. We present the (nearly) whole sequences of five new mt genomes in the Beta genus: four from Beta vulgaris and one from B. macrocarpa, a sister species belonging to the same Beta section. We pooled our results with two previously sequenced genomes of B. vulgaris and studied genome diversity at the species level with an emphasis on cytoplasmic male-sterilizing (CMS) genomes. We showed that, contrary to what was previously assumed, all three CMS genomes belong to a single sterile lineage. In addition, the CMSs seem to have undergone an acceleration of the rates of substitution and rearrangement. This study suggests that male sterility emergence might have been favored by faster rates of evolution, unless CMS itself caused faster evolution.
Assuntos
Beta vulgaris/genética , DNA Mitocondrial/genética , Variação Genética , Genoma Mitocondrial/genética , Sequência de Bases , Beta vulgaris/classificação , Mapeamento Cromossômico , Cromossomos de Plantas/genética , DNA de Cloroplastos/química , DNA de Cloroplastos/genética , DNA Mitocondrial/química , DNA de Plantas/química , DNA de Plantas/genética , Evolução Molecular , Genes Mitocondriais/genética , Genoma de Planta/genética , Genômica/métodos , Dados de Sequência Molecular , Mutação , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , SinteniaRESUMO
Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is a representative of the group of lactic acid-producing bacteria, mainly known for its worldwide application in yogurt production. The genome sequence of this bacterium has been determined and shows the signs of ongoing specialization, with a substantial number of pseudogenes and incomplete metabolic pathways and relatively few regulatory functions. Several unique features of the L. bulgaricus genome support the hypothesis that the genome is in a phase of rapid evolution. (i) Exceptionally high numbers of rRNA and tRNA genes with regard to genome size may indicate that the L. bulgaricus genome has known a recent phase of important size reduction, in agreement with the observed high frequency of gene inactivation and elimination; (ii) a much higher GC content at codon position 3 than expected on the basis of the overall GC content suggests that the composition of the genome is evolving toward a higher GC content; and (iii) the presence of a 47.5-kbp inverted repeat in the replication termination region, an extremely rare feature in bacterial genomes, may be interpreted as a transient stage in genome evolution. The results indicate the adaptation of L. bulgaricus from a plant-associated habitat to the stable protein and lactose-rich milk environment through the loss of superfluous functions and protocooperation with Streptococcus thermophilus.
Assuntos
Sequência de Bases , Evolução Molecular , Genoma Bacteriano , Lactobacillus delbrueckii/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Metabolismo dos Carboidratos , Sequências Repetitivas Dispersas , Lactobacillus delbrueckii/metabolismo , Dados de Sequência Molecular , Análise de Sequência de DNA , Streptococcus thermophilus/metabolismo , Sintenia , Iogurte/microbiologiaRESUMO
A dysmorphic newborn with 45,x,der(1)inv(1)(p13;qter)t(y;1)(pter-->q11;p13),-Y de novo karyotype: Y/autosome translocations are very rare chromosomal rearrangements. In most cases, the long arm of the Y chromosome is translocated onto an autosome and most patients are referred because of male infertility. Y/1 translocations are very rare, and have been reported in seven patients so far. Pericentric inversions may be seen in all chromosomes and are not associated with phenotypic abnormalities. Here we report a 6-day old male baby with prenatal growth retardation, frontal bossing, hypertelorism, micrognathia, cleft soft palate, absent uvula, hypospadias, simian line in both hands and hammer toes. Cytogenetic analysis was performed with GTG-banding, C-banding and FISH analysis containing X centromeric probe, Yq12-qter locus specific probe and whole chromosome Y probe. An unbalanced Y/1 translocation was diagnosed: 45,X,der(1)inv(1)(p13;qter)t(Y;1)(pter-->q11;p13),-Y.
Assuntos
Anormalidades Múltiplas/genética , Bandeamento Cromossômico , Deleção Cromossômica , Inversão Cromossômica/genética , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Y/genética , Anormalidades Craniofaciais/genética , Cariotipagem , Translocação Genética/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Craniofaciais/diagnóstico , Análise Mutacional de DNA , Loci Gênicos , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Masculino , Proteínas de Plasma Seminal/genética , Aberrações dos Cromossomos SexuaisRESUMO
A case of lobular carcinoma in a male breast is described. Because the structure of the male breast does not have lobules and acini, lobular carcinoma cases are seen infrequently. The pathological diagnosis was invasive lobular carcinoma of the breast. The karyotype of the patient revealed a 46 XY/46 XY, dmin (double minutes) chromosomal structure. Although 28% of the examined metaphases showed 46 XY, 1-5 dmin, the others were normal. We reviewed the English literature and found 20 reported cases of lobular carcinoma of the male breast. Our case represents lobular carcinoma in a proven genotypic male patient showing no exogenous or endogenous estrogens.
Assuntos
Neoplasias da Mama Masculina/patologia , Carcinoma Lobular/patologia , Neoplasias da Mama Masculina/genética , Carcinoma Lobular/genética , Humanos , Cariotipagem , Masculino , Pessoa de Meia-IdadeRESUMO
Despite the existence of some positive and negative reports on dantrolene in ischemic states, combined application of an endoplasmic reticulum Ca2+ release inhibitor and a calcium channel blocker has not yet been elucidated. In the present study, we have investigated the role of dantrolene in subsequent doses alone or in coexistence with the dihydropyridine calcium antagonist nimodipine (10(-4) M concentration) in glutamate-induced (10(-7) M) neurotoxicity in cerebellar granular cell cultures of rat pups. Glutamate induced neuronal cell death at a concentration of 10(-7) M. Despite the fact that none of the groups tested were able to reverse cell death to control values, dantrolene was found to be effective in preventing glutamate toxicity in cerebellar cultures of rat pups. The protective effect of dantrolene potentialized in combination with nimodipine at all doses tested. The most effective dose of dantrolene was found to be 10(-4)M in combination with nimodipine. As a result, both extracellular and internal calcium stores play important roles in the genesis of neuronal cell death induced by glutamate.
Assuntos
Dantroleno/farmacologia , Ácido Glutâmico/farmacologia , Neurônios/efeitos dos fármacos , Nimodipina/farmacologia , Análise de Variância , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Morte Celular/efeitos dos fármacos , Células Cultivadas , Interações Medicamentosas , Relaxantes Musculares Centrais/farmacologia , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-DawleyRESUMO
Glutamate (10(-7)m) and one of its non-NMDA receptor agonists, kainic acid (10(-4)m), were administered to rat cerebellar granular cell cultures, and the neuroprotective role of salicylic acid was examined. Glutamate induced 38.58 +/- 1.45% neuronal cell death while kainic acid induced only 21.4 +/- 2.01% despite being 1000 times more concentrated. The most effective dose for the neuroprotective effect of salicylate in glutamate-induced neurotoxicity was 10(-5)m and it had no protective effect at 10(-7)m. With kainic acid-induced toxicity, 10(-6)m salicylate had no protective effect but 10(-5)m and. 10(-4)m salicylic acid were very effective against kainic acid-induced toxicity. As an OH-trapping agent, salicylate had a protective role in NMDA and non-NMDA receptor-activated neuronal cell death. The present study gives some important clues about oxygen free radical generation having an important role in glutamate- and kainic acid-induced neurotoxicity. On the other hand, the neuroprotective effects of salicylic acid in the present study may depend on the pH alterations in salicylic acid solutions.
Assuntos
Cerebelo/efeitos dos fármacos , Ácido Glutâmico/toxicidade , Ácido Caínico/toxicidade , Fármacos Neuroprotetores/farmacologia , Ácido Salicílico/farmacologia , Animais , Células Cultivadas , Cerebelo/citologia , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Ratos , Ratos Sprague-DawleyRESUMO
To determine the genotoxic risk associated with diagnostic exposure to low doses of iodine 131 (131I), sister chromatid exchange (SCE) analysis was performed in lymphocytes of 18 non-smoking women who received 370 kBq (10 microCi) intravenous 131I sodium iodide as an adjuvant for scintigraphy for diagnosing thyroid nodularity. SCE frequencies were measured before and after 131I administration. SCE results in the pre-treated phase were regarded as control. Although SCE values 24 h after 131I administration did not show a significant increment (p > 0.05), there was a significant increase 72 h after treatment (p < 0.05). These results indicate that genetic damage might be induced by low dose of 131I.
Assuntos
Radioisótopos do Iodo , Troca de Cromátide Irmã/efeitos da radiação , Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Feminino , Marcadores Genéticos , Humanos , Injeções Intravenosas , Radioisótopos do Iodo/efeitos adversos , Linfócitos/efeitos da radiação , Pessoa de Meia-Idade , Mutagênese/efeitos da radiação , Cintilografia , Troca de Cromátide Irmã/genéticaRESUMO
A method for determination of trace amounts of Cu, Fe, Pb, Mn, Zn, Cd, Ni, Bi and Cr in aqueous solutions by flame atomic absorption spectrometry after coprecipitation by using a combination of sodium diethyldithiocarbamate as a chelating agent and cobalt as a carrier element was introduced. Different factors including amounts of reagents, pH of sample solution, standing time, sample volume for the precipitation and matrix effects were examined. Under selected conditions, the relative standard deviation of the combined method of sample treatment, coprecipitation and determination with flame AAS (n = 9) is generally about 3.5-6.9%; the limits of detection (3 s, n = 20) for the analytes were found to be between 4 and 64 microg 1(-1). The procedure was applied to the analysis of sea water and dialysis concentrate samples with quantitative recovery, > or =95%.
RESUMO
OBJECTIVE: This study investigated whether any genomic change occurs in DNA level in ankylosing spondylitis (AS) by measuring sister chromatid exchange (SCE) frequency. METHODS: SCE frequency was detected on metaphase chromosomes obtained from peripheral blood lymphocyte cultures in 15 patients diagnosed as having AS. SCE values were also obtained from 15 healthy subjects as a control group. SCE frequencies were detected from metaphases obtained from standard blood cultures by using bromodeoxyuridine and staining by Giemsa. RESULTS: SCE frequencies of AS were statistically higher than those of the control group (p < 0.005). CONCLUSION: These results suggest that genetic factors may play a more important part than realised in the aetiology of AS.
Assuntos
Troca de Cromátide Irmã , Espondilite Anquilosante/genética , Adulto , Feminino , Humanos , Linfócitos/fisiologia , Masculino , Metáfase , Pessoa de Meia-IdadeRESUMO
PURPOSE: Aminoglycoside-induced deafness has been described in a number of Chinese pedigrees. In nearly all of these families, affected individuals were related through the maternal side. Because mitochondrial DNA is transmitted exclusively through mothers, it had been speculated that a mutation in the mitochondrial DNA might predispose these maternally related family members to aminoglycoside ototoxicity. Recently, we analyzed three such families with multiple cases of ototoxic deafness and identified a pathogenic mutation in the mitochondrial 12S ribosomal RNA gene at nucleotide position 1555. The purpose of the current study is to analyze individuals with no family history of deafness, who had severe hearing loss after aminoglycoside exposure, for presence or absence of this particular mitochondrial DNA mutation. MATERIALS AND METHODS: Blood was obtained from 36 Chinese individuals who became deaf after aminoglycoside exposure and had no family history of deafness. The DNA of these individuals was extracted, amplified by the polymerase chain reaction, and analyzed for the mitochondrial ribosomal RNA gene mutation by allele-specific oligonucleotide hybridization and Southern blot analysis. RESULTS: In one of these 36 sporadic cases, we identified the nucleotide 1555 A-->G mutation in the mitochondrial genome. CONCLUSION: This finding implies that a small proportion of individuals at risk for aminoglycoside ototoxicity harbor the specific mitochondrial DNA mutation identified in the familial cases. In these individuals, a genetic susceptibility to the ototoxic effects of aminoglycosides can be diagnosed, and deafness can be prevented in maternal relatives by avoiding the use of these antibiotics.
Assuntos
Antibacterianos/efeitos adversos , DNA Mitocondrial/genética , Surdez/induzido quimicamente , Surdez/genética , Mutação Puntual , RNA Ribossômico/genética , Adolescente , Adulto , Aminoglicosídeos , Southern Blotting , Feminino , Humanos , Masculino , Sondas de Oligonucleotídeos , Reação em Cadeia da PolimeraseRESUMO
Maternally transmitted non-syndromic deafness was described recently both in pedigrees with susceptibility to aminoglycoside ototoxicity and in a large Arab-Israeli pedigree. Because of the known action of aminoglycosides on bacterial ribosomes, we analysed the sequence of the mitochondrial rRNA genes of three unrelated patients with familial aminoglycoside-induced deafness. We also sequenced the complete mitochondrial genome of the Arab-Israeli pedigree. All four families shared a nucleotide 1555 A to G substitution in the 12S rRNA gene, a site implicated in aminoglycoside activity. Our study offers the first description of a mitochondrial rRNA mutation leading to disease, the first cases of non-syndromic deafness caused by a mitochondrial DNA mutation and the first molecular genetic study of antibiotic-induced ototoxicity.