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1.
Front Microbiol ; 14: 1271983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38298542

RESUMO

Glyphosate is used worldwide as a compound of pesticides and is detectable in many environmental compartments. It enters water bodies primarily through drift from agricultural areas so that aquatic organisms are exposed to this chemical, especially after rain events. Glyphosate is advertised and sold as a highly specific herbicide, which interacts with the EPSP synthase, an enzyme of the shikimate metabolism, resulting in inhibition of the synthesis of vital aromatic amino acids. However, not only plants but also bacteria can possess this enzyme so that influences of glyphosate on the microbiomes of exposed organisms cannot be excluded. Those influences may result in subtle and long-term effects, e.g., disturbance of the symbiotic interactions of bionts with microorganisms of their microbiomes. Mechanisms how the transformation product aminomethylphosphonic acid (AMPA) of glyphosate might interfere in this context have not understood so far. In the present study, molecular biological fingerprinting methods showed concentration-dependent effects of glyphosate and AMPA on fish microbiomes. In addition, age-dependent differences in the composition of the microbiomes regarding abundance and diversity were detected. Furthermore, the effect of exposure to glyphosate and AMPA was investigated for several fish pathogens of gut microbiomes in terms of their gene expression of virulence factors associated with pathogenicity. In vitro transcriptome analysis with the fish pathogen Yersinia ruckeri revealed that it is questionable whether the observed effect on the microbiome is caused by the intended mode of action of glyphosate, such as the inhibition of EPSP synthase activity.

2.
Community Dent Health ; 39(3): 187-190, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35605103

RESUMO

OBJECTIVE: To investigate the relationships between dental anxiety, Facebook intrusion, and shame. METHODS: A sample of 498 adults aged 16-69 years completed an online questionnaire comprising the Modified Dental Anxiety Scale, the Facebook Intrusion Scale, and the Shame scale from the Test of Self-Conscious Affect. RESULTS: Dental anxiety was positively associated with Facebook intrusion. There were also indirect effects of dental anxiety on Facebook intrusion through shame. CONCLUSIONS: The results highlight the problem of dental anxiety in the context of Facebook intrusion risk. The findings may be applicable in Internet dependency prevention and treatment, focused on help in coping with the anxiety related to doctors' appointments.


Assuntos
Mídias Sociais , Adulto , Ansiedade , Ansiedade ao Tratamento Odontológico , Emoções , Humanos , Fatores de Risco , Inquéritos e Questionários
3.
Breast ; 43: 135-141, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30553188

RESUMO

INTRODUCTION: Metaplastic breast cancer (MpBC) is a rare but aggressive type of breast cancer accounting for 0.25-1% of all diagnosed invasive breast cancers. Morphologically, it is characterized by differentiation of the neoplastic epithelium into squamous cells and/or mesenchymal-looking tissue. MATERIAL AND METHODS: We analyzed 13 MpBCs selected from the group of 1122 invasive breast cancers. Histopathological examination and analysis of estrogen (ER), progesterone (PR) and HER2 receptors expression in MpBC patients and their comparison to other types of invasive breast cancer has been performed. RESULTS: 13 MpBC cases represented 1.16% of the 1122 invasive breast cancers. The MpBC group presented with a significantly larger tumor size (≥T2, 69% versus 49%, p < 0.001) and with higher grade of histological malignancy (G1-G3) (p < 0.001). MpBC group had significantly more cases with no hormone receptors (ER, PR) and HER2 overexpression/gene amplification compared with the other invasive breast cancer types group (ER-, 69% versus 23%, p < 0.001; PR-, 69% versus 28%, p < 0.001; HER2 0/1+, 93% versus 82%, p = 0.019). Most MpBCs (62%) were triple-negative. We found a correlation between hormone receptors expression and lymph node metastasis (p < 0.001). The analysis of the HER2 expression allowed us to find correlation between its expression and tumor histological grade (G1-G3) (p < 0.001), tumor size (T1a-T4) (p < 0.001) and lymph node metastasis (pN0-pN4) (p < 0.001) in MpBCs. DISCUSSION: MpBCs are usually larger at primary diagnosis and most of MpBCs present with other poor prognostic indicators and show lack of steroid hormone receptors expression as well as HER2. Hormone receptor status and HER2 expression seems to correlate with histological grade of malignancy (G1-G3), tumor size (T1a-T4) and regional lymph node involvement (pN0-pN4) and these features are directly related to MpBC malignancy.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Adenoescamoso/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Receptor alfa de Estrogênio/metabolismo , Mioepitelioma/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Adenoescamoso/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mioepitelioma/patologia , Gradação de Tumores , Invasividade Neoplásica , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral
4.
Transplant Proc ; 50(6): 1686-1690, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30056882

RESUMO

INTRODUCTION: The approach toward transplanting kidneys from expanded-criteria donors (ECDs) in Poland is largely site-dependent. The Kidney Donor Risk Index (KDRI) allows for obtaining a more precise characteristic of ECDs and further stratification into "better" and "worse" quality grafts. METHODS: Comparison of the incidence of delayed graft function (DGF) and biopsy-proven acute rejection (BPAR), median of hospitalization time and median of estimated glomerular filtration rate (eGFR) at 1 year after transplantation among kidney graft recipients (n = 468), divided by donor status (ECD/standard-criteria donor [SCD]) and KDRI value (I: 0.67-1.2, II: 1.21-1.6, III: 1.61-2.0, IV: 2.01-3.48). RESULTS: ECD kidneys have been transplanted to 32.47% of recipients. There were no ECD recipients in KDRI compartment I, 16.55% in compartment II, 79.22% in compartment III, and 100% in IV. In KDRI compartment II, DGF was diagnosed in 34.9% of SCDs and 56% of ECDs (P = .003), BPAR occurred in 7.8% of SCDs and 16% of ECDs (P = .073), median hospital stay was 12 days for SCDs and ECDs (P = 1), and eGFR was 50.7 mL/min for SCDs and 49.4 mL/min for ECDs (P = .734). In KDRI compartment III, DGF was diagnosed in 43.8% of SCDs and 49.2% of ECDs (P = .139), BPAR occurred in 6.3% of SCDs and 31.7% of ECDs (P = .001), median hospital stay was 10 days for SCDs and 12 days for ECDs (P = .634), and eGFR was 49.5 mL/min for SCDs and 45.2 mL/min for ECDs (P = .382). Among ECD recipients, DGF was diagnosed in 56.0%, 49.2%, and 47.7% of patients for KDRI compartments II, III, and IV respectively (P = .776); BPAR occurred in 16% (compartment II), 31.7% (compartment III), and 23.1% (compartment IV) (P = .273); the median hospital stay was 12 days (compartment II), 12 days (compartment III), and 12.5 days (compartment IV) (P = 1); and eGFR was 49.5 mL/min (compartment II), 45.4 mL/min (compartment III), and 36.1 mL/min (compartment IV) (P = .002). CONCLUSION: Assessment using both the ECD and KDRI systems allows for a more precise evaluation of prognosis and predicting complications among recipients.


Assuntos
Função Retardada do Enxerto/etiologia , Seleção do Doador/estatística & dados numéricos , Rejeição de Enxerto/etiologia , Transplante de Rim/efeitos adversos , Adulto , Idoso , Função Retardada do Enxerto/epidemiologia , Feminino , Taxa de Filtração Glomerular , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Incidência , Rim/fisiopatologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Polônia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Transplantes/fisiopatologia , Resultado do Tratamento
5.
J Physiol Pharmacol ; 69(2)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29980142

RESUMO

Growth hormone (GH) affects carbohydrate metabolism through direct negative effect on insulin sensitivity and indirectly, via insulin-like growth factor-1 (IGF-1), which exerts positive insulin-mimetic action. The aim of this retrospective study was to evaluate the influence of long-term GH treatment on glucose homeostasis in 118 children with isolated idiopathic GH deficiency (GHD). Based on this analysis we wanted to determine the usefulness of glycated haemoglobin (HbA1c) and parameters derived from the oral glucose tolerance test (OGTT) in the monitoring of disturbed glucose metabolism during GH treatment and to assess the value of IGF-1 in prediction of those changes. Mean duration of GH treatment was 2.5 ± 1.2 years. Data were analysed in the whole group and according to baseline pubertal status. Significant increases in insulin concentrations, both fasting and during the OGTT, accompanied by a significant increase in fasting glucose and unchanged glucose concentrations during the OGTT, were found after the initiation of GH treatment. HbA1c did not change significantly during GH treatment in comparison to baseline values and remained normal, even in patients with impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) found during GH treatment. Changes in glucose metabolism observed after the onset of GH treatment were related to increment in IGF-1 SDS and to GH doses. Significant associations between changes in IGF-1 SDS in the first year of GH treatment and some of the glucose metabolism parameters evaluated after the first, the second and the third year of GH treatment were also confirmed in multiple regression analysis after taking the GH dose into consideration. All cases of IFG and/or IGT detected during GH treatment are reversible after dietary intervention, independently of pubertal status, and do not lead to diabetes mellitus.


Assuntos
Glucose/metabolismo , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Adolescente , Criança , Pré-Escolar , Feminino , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Humanos , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/análise , Masculino
6.
J Mol Recognit ; 30(12)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28621027

RESUMO

Phosphoinositides are phosphatidylinositol derived, well known to be second messengers in various cell signaling pathways as well as in processes such as cell differentiation, cellular stress response, gene transcription, and chromatin remodeling. The pleckstrin homology domain of phospholipase C-delta 1 is responsible for recognizing and binding to PI(4,5)P2 and for this reason has been widely used to study this phosphoinositide as a biosensor when it is conjugated to a fluorescent tag. In this work, we modified the primary structure of pleckstrin homology domain by site-specific mutagenesis to change the specificity for phosphoinositides. We obtained 3 mutants: K30A, W36F, and W36Y with different specificity to phosphoinositides. Mutant domain K30A recognized PI(4,5)P2 , PI(3,4,5)P3 , phosphatidic acid (PA), and weakly PI(3,5)P2 . Mutant domain W36F recognized all the phosphoinositides studied and the PA. Finally, mutant domain W36Y seemed to interact with PA and all the other phosphoinositides studied, except PI(3)P. The changes in recognition argue against a simple charge and nonpolar region model for these interactions and more in favor of a specific docking region with a specific recognition site. We conducted in silico modeling that explains the mechanisms behind the observed changes and showed that aromatic amino acids appear to play more important role, than previously thought, in the specificity of phospholipids' binding domains.


Assuntos
Aminoácidos Aromáticos/química , Domínios de Homologia à Plecstrina , Sequência de Aminoácidos , Animais , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosfolipase C delta/química , Ratos
7.
Clin Otolaryngol ; 42(5): 994-999, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28107611

RESUMO

OBJECTIVE: To translate and adapt the original Singing Voice Handicap Index (SVHI) for the Polish population and to evaluate the psychometric properties of the Polish SVHI version, such as internal consistency, reliability and construct validity in different groups of dysphonic singers. STUDY DESIGN: Prospective case-control study. SETTING: Patients treated at a single institute. PARTICIPANTS: Sixty singers with voice disorders and 57 healthy singers completed the SVHI and the Voice Handicap Index (VHI). Thirty singers completed the SVHI twice within a 2- to 4-week interval. MAIN OUTCOME MEASURES: Internal consistency, test-retest reliability, discriminant validity, criterion-related validity RESULTS: A strong Cronbach's alpha coefficient (0.96) indicates that the SVHI items are measuring the same construct. Evaluating the test-retest reliability, the r-Spearman correlation coefficient was r = 0.797 for the total score of SVHI, which shows a good level of reproducibility. There were significant differences between the control group (CG) and patients with benign vocal fold lesions (P < 0.001), CG and singers with muscle tension dysphonia (P < 0.001), CG and coexistence of muscle tension dysphonia and chronic laryngitis (P < 0.001). There was a positive statistically significant correlation between SVHI and VHI (r = 0.753, P = 0.000*). CONCLUSIONS: The Polish version of SVHI serves as a valid health status instrument, as well as discriminating between singers with voice disorders and singers without voice problems. The SVHI is easy to perform in clinical practice.


Assuntos
Canto , Distúrbios da Voz/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Estudos Prospectivos , Psicometria , Reprodutibilidade dos Testes , Distúrbios da Voz/fisiopatologia , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-26843898

RESUMO

BACKGROUND: Mutations in the BRCA1, BRCA2 and PALB2 genes are well-established risk factors for the development of breast and/or ovarian cancer. The frequency and spectrum of mutations in these genes has not yet been examined in the population of Southern Poland. METHODS: We examined the entire coding sequences of the BRCA1 and BRCA2 genes and genotyped a recurrent mutation of the PALB2 gene (c.509_510delGA) in 121 women with familial and/or early-onset breast or ovarian cancer from Southern Poland. RESULTS: A BRCA1 mutation was identified in 11 of 121 patients (9.1 %) and a BRCA2 mutation was identified in 10 of 121 patients (8.3 %). Two founder mutations of BRCA1 accounted for 91 % of all BRCA1 mutation carriers (c.5266dupC was identified in six patients and c.181 T > G was identified in four patients). Three of the seven different BRCA2 mutations were detected in two patients each (c.9371A > T, c.9403delC and c.1310_1313delAAGA). Three mutations have not been previously reported in the Polish population (BRCA1 c.3531delT, BRCA2 c.1310_1313delAAGA and BRCA2 c.9027delT). The recurrent PALB2 mutation c.509_510delGA was identified in two patients (1.7 %). CONCLUSIONS: The standard panel of BRCA1 founder mutations is sufficiently sensitive for the identification of BRCA1 mutation carriers in Southern Poland. The BRCA2 mutations c.9371A > T and c.9403delC as well as the PALB2 mutation c.509_510delGA should be included in the testing panel for this population.

9.
Urologe A ; 54(4): 516-25, 2015 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-25895564

RESUMO

BACKGROUND: The histopathological structure of malignant tumours involves two essential compartments - the tumour parenchyma with the actual transformed cells, and the supportive tumour stroma. The latter consists of specialized mesenchymal cells, such as fibroblasts, macrophages, lymphocytes and vascular cells, as well as of their secreted products, including components of the extracellular matrix, matrix modifying enzymes and numerous regulatory growth factors and cytokines. In consequence, the tumour stroma has the ability to influence virtually all aspects of tumour development and progression, including therapeutic response. AIM: In this article we review the current knowledge of tumor stroma interactions in urothelial carcinoma and present various experimental systems that are currently in use to unravel the biological basis of these heterotypic cell interactions. RESULTS: For urothelial carcinoma, an extensive tumour stroma is quite typical and markers of activated fibroblasts correlate significantly with clinical parameters of advanced disease. Another clinically important variable is provided by the stromal expression of syndecan-1. CONCLUSION: Integration of markers of activated stroma into clinical risk evaluation could aid to better stratification of urothelial bladder carcinoma patients. Elucidation of biological mechanisms underlying tumour-stroma interactions could provide new therapeutical targets.


Assuntos
Proteínas de Neoplasias/metabolismo , Microambiente Tumoral , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Urotélio/metabolismo , Urotélio/patologia , Animais , Comunicação Celular , Humanos , Modelos Biológicos
10.
J Physiol Pharmacol ; 65(3): 449-54, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24930518

RESUMO

Irisin induces the browning of adipose tissue. The goal of this study was to investigate the influence of acute exercise in untrained and trained rats and endurance training on FNDC5 mRNA and irisin levels in white and red skeletal muscle and serum. Rats (n=60) were randomly divided into two groups: untrained and trained (subjected to 6-week endurance training with increasing load). Subgroups of rats from each group were sacrificed before (controls), immediately after, or 3 hours following acute exercise with the same work load. Muscle samples (red and white) and serum were collected. FNDC5 mRNA was evaluated using RT-PCR. Irisin levels were measured using an immunoenzymatic method. Muscle FNDC5 mRNA decreased immediately after acute exercise compared with baseline levels, but not in red muscle in trained rats. Atrend toward a return to baseline appeared 3 hours after the exercise, but only in white muscle in untrained group. Irisin protein levels increased after acute exercise in red muscle 3 hours post-exercise compared with samples taken immediately after exercise, and decreased 3 hours post-exercise compared to pre-exercise level in white muscles. FNDC5 mRNA did not change following training, whereas irisin protein levels increased in red muscle and decreased in white muscle. Serum irisin levels remained unchanged following acute exercise and training. We concluded that changes in irisin mRNA and protein levels in rat muscle after acute exercise are limited and depend on training status and the muscle type. Irisin serum levels remained stable after acute exercise or endurance training.


Assuntos
Fibronectinas/sangue , Condicionamento Físico Animal/fisiologia , Resistência Física/fisiologia , Animais , Masculino , Ratos , Ratos Wistar
11.
Tsitol Genet ; 41(4): 56-8, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18030727

RESUMO

The results of study of micronuclei (MN) frequencies among the participants of Ukrainian school biological olympiads are presented. Totally 266 persons have been inspected. The distribution of MN frequencies correspond to the Poisson's distribution with lambda = 2.5. The average frequency of micronuclei in males was 2.4 +/- 0.15%, in females it was 2.7 +/- 0.14%. The difference of the average MN frequencies for these two groups was statistically insignificant. The individual micronuclei frequencies varied from 0 to 8.3%, the average MN frequency in the general group was 2.5 +/- 0.11%, (limits 2-5%). The micronuclei frequencies in different age groups of males and females were compared. Significantly higher MN frequencies in females than in males at the age of sixteen were detected. The age-related changes of micronuclei frequencies (14-18 age) were different for females compared to males.


Assuntos
Envelhecimento/genética , Instabilidade Genômica , Micronúcleos com Defeito Cromossômico , Mucosa Bucal , Caracteres Sexuais , Adolescente , Feminino , Humanos , Masculino , Micronúcleos com Defeito Cromossômico/estatística & dados numéricos , Testes para Micronúcleos , Mucosa Bucal/citologia , Distribuição de Poisson , Ucrânia
12.
J Gravit Physiol ; 14(1): P109-10, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18372723

RESUMO

The changes in the fundamental biological processes of nuclear RNA transcription and splicing under altered gravity conditions are still unclear. The quantitative and qualitative characteristics of the proteins involved in nuclear RNA metabolism in control and under clinorotation were investigated by two-dimensional gel electrophoresis. We revealed firstly a decrease in the isoelectric point range of nuclear soluble proteins, which are known to be actively engaged in nuclear RNA metabolism, and a shortening in the molecular weight range of them under clinorotation. Moreover, minor and major proteins in clinorotated samples had decreased optical densities in comparison with control ones. Our results are in agreement with the hypothesis that a rearrangement of the pattern of nuclear proteins involved in gene expression processes occurs in seedlings grown and developed in altered gravity.


Assuntos
Núcleo Celular/metabolismo , Gravidade Alterada , Lepidium sativum/metabolismo , Meristema/metabolismo , Proteínas de Plantas/metabolismo , Proteômica , Rotação , Adaptação Fisiológica , Eletroforese em Gel Bidimensional , Regulação da Expressão Gênica de Plantas , Ponto Isoelétrico , Lepidium sativum/genética , Meristema/citologia , Peso Molecular , Proteínas de Plantas/química , Proteômica/métodos , Splicing de RNA , RNA Nuclear/metabolismo , RNA de Plantas/metabolismo , Ribonucleoproteínas/metabolismo , Transcrição Gênica
13.
J Gravit Physiol ; 14(1): P117-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18372727

RESUMO

The study of the influence of weak, alternating magnetic field, which was adjusted to the cyclotron frequency of Ca2+ and K+ ions, on the fusion of tobacco and soya protoplasts was carried out using the extra apparatus with ferromagnetic shield. An increase in the frequency of protoplasts fusion in 2-3 times and participation of calcium ions in the induction of protoplast fusion in weak alternating magnetic field have been established.


Assuntos
Cálcio/metabolismo , Campos Eletromagnéticos , Glycine max/fisiologia , Fusão de Membrana , Nicotiana/fisiologia , Protoplastos/fisiologia , Ciclotrons , Compostos Férricos , Microscopia Confocal , Potássio/metabolismo , Protoplastos/metabolismo , Glycine max/metabolismo , Fatores de Tempo , Nicotiana/metabolismo
14.
Protoplasma ; 228(4): 209-19, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16838080

RESUMO

Fibrillarin and the plant nucleolin homolog NopA64 are two important nucleolar proteins involved in pre-rRNA processing. In order to determine the effects of the altered gravity environment on the nucleolus, we have investigated the location of fibrillarin and NopA64 in nucleolar subcomponents of cress (Lepidium sativum L.) root meristematic cells grown under clinorotation, which reproduces an important feature of microgravity, namely, the absence of the orienting action of a gravity vector, and compared it to the location in control cells grown in normal 1 g conditions. Prior to these experiments, we report here the characterization of cress fibrillarin as a 41 kDa protein which can be isolated from meristematic cells in three nuclear fractions, namely, the soluble ribonucleoprotein fraction, the chromatin fraction, and the nuclear-matrix fraction. Furthermore, as reported for other species, the location of both fibrillarin and NopA64 in the cress cell nucleolus was in zones known to contain complex ribonucleoprotein particles involved in early pre-rRNA processing, i.e., processomes. Under altered gravity, a decrease in the quantity of both fibrillarin and NopA64 compared to controls was observed in the transition zone between fibrillar centers and the dense fibrillar component, as well as in the bulk of the dense fibrillar component. These data suggest that altered (reduced) gravity results in a lowered level of functional activity in the nucleolus.


Assuntos
Proteínas Cromossômicas não Histona/análise , Gravidade Alterada , Lepidium sativum/metabolismo , Meristema/metabolismo , Fosfoproteínas/análise , Raízes de Plantas/metabolismo , Proteínas de Ligação a RNA/análise , Western Blotting , Nucléolo Celular/metabolismo , Nucléolo Celular/ultraestrutura , Lepidium sativum/citologia , Lepidium sativum/ultraestrutura , Meristema/citologia , Meristema/ultraestrutura , Microscopia Imunoeletrônica/métodos , Proteínas Nucleares/análise , Raízes de Plantas/citologia , Raízes de Plantas/ultraestrutura , Nucleolina
15.
Tsitol Genet ; 40(1): 43-8, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16792020

RESUMO

The functions of the nucleolus responsible for the biosynthesis of ribosomes in altered gravity are still unclear. The location of nucleolar DNA both in control and simulated microgravity has been investigated using fluorescent and immunogold cytochemistry. We have determined the redistribution of rDNA in the nucleolar components accompanied by their ultrastructure changes. According to this the lowering of rDNA transcription level under simulated microgravity was supposed.


Assuntos
Nucléolo Celular/metabolismo , DNA de Plantas/metabolismo , DNA Ribossômico/metabolismo , Lepidium sativum/metabolismo , Simulação de Ausência de Peso , Nucléolo Celular/ultraestrutura , Cromatina/metabolismo , Imuno-Histoquímica , Lepidium sativum/crescimento & desenvolvimento , Lepidium sativum/ultraestrutura , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Meristema/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica
16.
Tsitol Genet ; 39(1): 52-62, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16018178

RESUMO

Fibrillarin and plant nucleolin homologue NopA64 are two important nucleolar proteins involved in pre-rRNA processing. To understand better the effects of the altered gravity environment on the nucleolus functioning we have investigated the location of fibrillarin and NopA64 in nucleolar subcomponents of cress (Lepidium sativum L.) root meristematic cells grown under simulated microgravity that was compared to the control cells grown in normal conditions at I g. Cress fibrillarin was first shown to have the molecular weight 41 kDa. Both fibrillarin and NopA64 in the cress cell nucleolus are located in the zones known to contain processing pre-rRNA molecules as it has been previously reported in other species. The data confirm participation of these proteins in processomes--RNP complex particles involved in pre-rRNA processing. Under altered gravity a decrease in the quantity of both fibrillarin and NopA64 in the transition zone between fibrillar centres and the dense fibrillar component was observed, compared to control, which could point out to a lowering of the level of early pre-rRNA processing in these experimental conditions. This decrease was also detected in the bulk of the dense fibrillar component. These data support the idea that altered (reduced) gravity results in lowering the level of functional activity of the nucleolus.


Assuntos
Nucléolo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Gravidade Alterada , Processamento Pós-Transcricional do RNA , RNA de Plantas/metabolismo , RNA Ribossômico/metabolismo , Nucléolo Celular/ultraestrutura , Imuno-Histoquímica , Lepidium sativum/metabolismo , Lepidium sativum/ultraestrutura , Meristema/metabolismo , Meristema/ultraestrutura
17.
J Gravit Physiol ; 11(2): P189-90, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16237832

RESUMO

The functions of the nucleolus responsible for the biosynthesis of ribosomes in altered gravity are still unclear. The location of nucleolar DNA both in control and simulated microgravity with fluorescent and immunogold cytochemistry was investigated. We determined firstly the redistribution of rDNA in the nucleolar components accompanied with the changes in their ultrastructure. According to it, lowering the level of rDNA transcription in simulated microgravity was firstly proposed.


Assuntos
Nucléolo Celular/metabolismo , DNA de Plantas/metabolismo , DNA Ribossômico/metabolismo , Lepidium sativum/metabolismo , Simulação de Ausência de Peso , Nucléolo Celular/ultraestrutura , Cromatina , Gravidade Alterada , Imuno-Histoquímica , Lepidium sativum/ultraestrutura , Meristema/metabolismo , Meristema/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica , Rotação
18.
Tsitol Genet ; 37(4): 40-5, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14569622

RESUMO

For the first time, in altered gravity, with antifibrillarin antibodies and immunogold microscopy fibrillarin that is one of the most important proteins of rRNA processing was localized. The quantitative study of the density of gold particles in the nuclelous, under clinorotation both the transition zone FC-DFC and the dense fibrillar component were less labeled as compared to the control. Obtained data allow us to suppose the lowering of the rRNA processing level in the nucleoli under the influence of altered gravity.


Assuntos
Nucléolo Celular/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Gravidade Alterada/efeitos adversos , Lepidium sativum/fisiologia , Ribonucleoproteínas/metabolismo , Anticorpos/metabolismo , Nucléolo Celular/ultraestrutura , Proteínas Cromossômicas não Histona/imunologia , Proteínas Cromossômicas não Histona/ultraestrutura , Imuno-Histoquímica , Lepidium sativum/citologia , Processamento Pós-Transcricional do RNA , RNA Ribossômico/metabolismo , Ribonucleoproteínas/imunologia , Ribonucleoproteínas/ultraestrutura , Rotação
19.
Artigo em Inglês | MEDLINE | ID: mdl-12019949

RESUMO

The resistance of 167 pathogenic bacteria of animal origin to quinolones was determined by the disc diffusion method, and by the minimum inhibitory concentration (MIC) test. The highest resistance of Escherichia coli was found to be against nalidixic acid (NA), 49.1% and flumequine (FLU), 38.2%. The sensitivity of the strains were: ciprofloxacin (CIP; 81.8%); enrofloxacin (ENR; 81.8%); norfloxacin (NOR; 80.0%); and pefloxacin (PE; 76.4%). Salmonella spp. showed 100% sensitivity to CIP, ENR, NOR and PE. A high resistance percentage in the cases of: FLU (86.7%); PE (50.0%); and CIP (26.65%) distinguished the Streptococcus spp. The highest percentage sensitivity of Staphylococci was found with three fluoroquinolones: CIP, ENR and NOR, 94.3% each (66 strains). The studies did not indicate that a total cross-resistance might occur between the examined quinolones.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana , Fluoroquinolonas , Ácido Nalidíxico/farmacologia , Quinolizinas/farmacologia , Animais , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Polônia , Salmonella/classificação , Salmonella/efeitos dos fármacos , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos
20.
J Gravit Physiol ; 8(1): P43-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12638617

RESUMO

A nucleolus is the dynamic part of a cell nucleus where rDNA transcription, rRNA precursor processing and transport are proceeding. Investigations of the influence of microgravity and clinorotation on the structure and function of nucleolus began more than thirty years ago but, unfortunately, now there are only some articles concerning the nucleolar peculiarities in altered gravity. Available data about alterations of nucleolar morphology and function under the influence of high and low temperature, hypoxia and UV-microbeam irradiation allow us to put intent attention to the study of the nucleolus reactions on clinorotation. Therefore, the aim of our work was to investigate the ultrastructural organization and functional activity of nucleoli in Lepidium sativum root meristematic cells under clinorotation in order to understand whether a nucleolus can react to gravity.


Assuntos
Nucléolo Celular/fisiologia , Lepidium sativum/ultraestrutura , Meristema/ultraestrutura , Rotação , Simulação de Ausência de Peso , Nucléolo Celular/ultraestrutura , Núcleo Celular/fisiologia , Cromatina/metabolismo , Gravidade Alterada , Lepidium sativum/crescimento & desenvolvimento , Lepidium sativum/fisiologia , Meristema/crescimento & desenvolvimento , Meristema/fisiologia , Microscopia Eletrônica , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Raízes de Plantas/ultraestrutura , Vacúolos/fisiologia
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