Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 273
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Microsc ; 282(1): 21-29, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33089519

RESUMO

Exocytosis of peptides and steroids stored in a dense core vesicular (DCV) form is the final step of every secretory pathway, indispensable for the function of nervous, endocrine and immune systems. The lack of live imaging techniques capable of direct, label-free visualisation of DCV release makes many aspects of the exocytotic process inaccessible to investigation. We describe the application of correlative scanning ion conductance and fluorescence confocal microscopy (SICM-FCM) to study the exocytosis of individual granules of insulin from the top, nonadherent, surface of pancreatic ß-cells. Using SICM-FCM, we were first to directly follow the topographical changes associated with physiologically induced release of insulin DCVs. This allowed us to report the kinetics of the full fusion of the insulin vesicle as well as the subsequent solubilisation of the released insulin crystal.


Assuntos
Células Secretoras de Insulina , Insulina , Exocitose , Microscopia Confocal , Microscopia de Fluorescência , Vesículas Secretórias
2.
Folia Biol (Praha) ; 65(5-6): 203-211, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32362303

RESUMO

Transcription factors exert their regulatory potential on RNA polymerase II machinery through a multiprotein complex called Mediator complex or Mediator. The Mediator complex integrates regulatory signals from cell regulatory cascades with the regulation by transcription factors. The Mediator complex consists of 25 subunits in Saccharomyces cerevisiae and 30 or more subunits in multicellular eukaryotes. Mediator subunit 28 (MED28), along with MED30, MED23, MED25 and MED26, belong to presumably evolutionarily new subunits that seem to be absent in unicellular eukaryotes and are likely to have evolved together with multicellularity and cell differentiation. Previously, we have shown that an originally uncharacterized predicted gene, F28F8.5, is the true MED28 orthologue in Caenorhabditis elegans (mdt-28) and showed that it is involved in a spectrum of developmental processes. Here, we studied the proteomic interactome of MDT-28 edited as GFP::MDT-28 using Crispr/Cas9 technology or MDT-28::GFP expressed from extrachromosomal arrays in transgenic C. elegans exploiting the GFPTRAP system and mass spectrometry. The results show that MDT-28 associates with the Head module subunits MDT-6, MDT-8, MDT-11, MDT-17, MDT- 20, MDT-22, and MDT-30 and the Middle module subunit MDT-14. The analyses also identified additional proteins as preferential MDT-28 interactants, including chromatin-organizing proteins, structural proteins and enzymes. The results provide evidence for MDT-28 engagement in the Mediator Head module and support the possibility of physical (direct or indirect) interaction of MDT-28 with additional proteins, reflecting the transcription-regulating potential of primarily structural and enzymatic proteins at the level of the Mediator complex.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Complexo Mediador/metabolismo , Proteínas Nucleares/metabolismo , Subunidades Proteicas/metabolismo , Proteômica , Alelos , Animais , Ligação Proteica
3.
Eur Cell Mater ; 34: 128-141, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28929469

RESUMO

Tissue engineering-based therapies targeting cartilage diseases, such as osteoarthritis, require in vitro expansion of articular chondrocytes. A major obstacle for these therapies is the dedifferentiation and loss of phenotype accompanying chondrocyte expansion. Recent studies suggest that manipulation of hedgehog signalling may be used to promote chondrocyte re-differentiation. Hedgehog signalling requires the primary cilium, a microtubule-based signalling compartment, the integrity of which is linked to the cytoskeleton. We tested the hypothesis that alterations in cilia expression occurred as consequence of chondrocyte dedifferentiation and influenced hedgehog responsiveness. In vitro chondrocyte expansion to passage 5 (P5) was associated with increased actin stress fibre formation, dedifferentiation and progressive loss of primary cilia, compared to primary (P0) cells. P5 chondrocytes exhibited ~50 % fewer cilia with a reduced mean length. Cilia loss was associated with disruption of ligand-induced hedgehog signalling, such that P5 chondrocytes did not significantly regulate the expression of hedgehog target genes (GLI1 and PTCH1). This phenomenon could be recapitulated by applying 24 h cyclic tensile strain, which reduced cilia prevalence and length in P0 cells. LiCl treatment rescued cilia loss in P5 cells, partially restoring hedgehog signalling, so that GLI1 expression was significantly increased by Indian hedgehog. This study demonstrated that monolayer expansion disrupted primary cilia structure and hedgehog signalling associated with chondrocyte dedifferentiation. This excluded the possibility to use hedgehog ligands to stimulate re-differentiation without first restoring cilia expression. Furthermore, primary cilia loss during chondrocyte expansion would likely impact other cilia pathways important for cartilage health and tissue engineering, including transforming growth factor (TGF), Wnt and mechanosignalling.


Assuntos
Condrócitos/citologia , Cílios/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Actinas/metabolismo , Animais , Cartilagem Articular/citologia , Bovinos , Desdiferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Ligantes , Cloreto de Lítio/farmacologia , Fenótipo , Polimerização , Transdução de Sinais/efeitos dos fármacos , Suporte de Carga
4.
BMC Cancer ; 16(1): 795, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733154

RESUMO

BACKGROUND: This study addresses involvement of major 5-fluorouracil (5-FU) pathway genes in the prognosis of colorectal carcinoma patients. METHODS: Testing set and two validation sets comprising paired tumor and adjacent mucosa tissue samples from 151 patients were used for transcript profiling of 15 5-FU pathway genes by quantitative real-time PCR and DNA methylation profiling by high resolution melting analysis. Intratumoral molecular profiles were correlated with clinical data of patients. Protein levels of two most relevant candidate markers were assessed by immunoblotting. RESULTS: Downregulation of DPYD and upregulation of PPAT, UMPS, RRM2, and SLC29A1 transcripts were found in tumors compared to adjacent mucosa in testing and validation sets of patients. Low RRM2 transcript level significantly associated with poor response to the first-line palliative 5-FU-based chemotherapy in the testing set and with poor disease-free interval of patients in the validation set irrespective of 5-FU treatment. UPP2 was strongly methylated while its transcript absent in both tumors and adjacent mucosa. DPYS methylation level was significantly higher in tumor tissues compared to adjacent mucosa samples. Low intratumoral level of UPB1 methylation was prognostic for poor disease-free interval of the patients (P = 0.0002). The rest of the studied 5-FU genes were not methylated in tumors or adjacent mucosa. CONCLUSIONS: The observed overexpression of several 5-FU activating genes and DPYD downregulation deduce that chemotherapy naïve colorectal tumors share favorable gene expression profile for 5-FU therapy. Low RRM2 transcript and UPB1 methylation levels present separate poor prognosis factors for colorectal carcinoma patients and should be further investigated.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias Colorretais/genética , Fluoruracila/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Transcriptoma , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Ilhas de CpG , Metilação de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Ribonucleosídeo Difosfato Redutase/genética , Ribonucleosídeo Difosfato Redutase/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Acta Chir Plast ; 58(2): 70-76, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28079392

RESUMO

A variety of surgical techniques has been used to correct hypoplastic breast malformations and deformities, including tissue expanders, breast implants, custom chest wall implants, mammary gland remodelling, as well as locoregional or free flap. Case series of successful breast reconstruction using lipomodelling technique in one patient with severe Polands syndrome and two patients with tuberous breasts are reported together with literature review. No surgical complications were observed and ultrasound examination did not reveal any pathology in breast tissue other than oil pseudocysts postoperatively. In both malformations, submammary fold was moved downwards. Moreover, the lower part of the breast and areolar herniation was corrected in tuberous breast, and in Polands syndrome, the areolar complex was significantly shifted downwards and laterally. In comparison with other reconstructive techniques, lipomodelling allows for the breast correction to begin in early adolescence. Further growth of the unaffected breast may be effectively corrected by subsequent lipomodelling session. This technique appears to change the overall approach to the management of hypoplastic breast and chest wall malformations.


Assuntos
Tecido Adiposo/transplante , Mama/cirurgia , Mamoplastia/métodos , Síndrome de Poland/cirurgia , Adolescente , Mama/anormalidades , Feminino , Humanos , Adulto Jovem
6.
Klin Onkol ; 29(4): 279-86, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27534785

RESUMO

BACKGROUND: Gastric cancer is a malignant disease with a poor prognosis. The incidence of gastric cancer in the Czech Republic in 2013 was 14.34 cases per 100,000 citizens. Unfortunately, most patients are dia-gnosed with advanced stage disease and therefore undergo palliative treatment. Some patients undergo surgery and a very small percentage undergo palliative chemotherapy. The five year survival rate for those with advanced gastric cancer ranges from 5-15%. METHODS: This is a prospective study of patients undergoing chemotherapy for advanced gastric cancer. The aim was to assess the quality of life of those undergoing chemotherapy. RESULTS: The results showed that chemotherapy reduced the quality of life for these patients. DISCUSSION: Although palliative chemotherapy prolonged time to progression, it had little impact on overall survival. Conversely, chemotherapy reduced quality of life. Thus, clinicians and patients must decide whether to begin palliative chemotherapy. The final decision should be made by the patient after discussion with the treating clinician. CONCLUSION: Treatment of patients with gastric cancer must be undertaken on an individual basis. Those undergoing palliative treatment must play an active role in the decision process regarding chemotherapy and assess the potential benefits and drawbacks. Because chemotherapy treatment has a detrimental effect on quality of life, the decision should be based on factors that predict the likely therapeutic effect of chemotherapy. A definitive decision can then be made as to whether chemotherapy is indicated. KEY WORDS: gastric cancer - palliative chemotherapy - chemotherapy - quality of life - WHOQOL-BREFThis study was supported by grant of Internal Grant Agency of the Czech Ministry of Health No. NS14227-3.The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 10. 1. 2016Accepted: 8. 6. 2016.


Assuntos
Antineoplásicos/uso terapêutico , Cuidados Paliativos , Qualidade de Vida , Neoplasias Gástricas/tratamento farmacológico , Intervalo Livre de Doença , Humanos , Estudos Prospectivos , Neoplasias Gástricas/patologia
7.
Rozhl Chir ; 95(5): 200-2, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27336748

RESUMO

INTRODUCTION: Primary omental torsion is a rare finding in cases of suspected acute abdomen. It is more common in children. Secondary omental torsion is typical for adults. CASE REPORT: The authors describe two cases where pain in the right upper abdominal quadrant was caused by primary torsion of the omental corner due to increased intraabdominal pressure: after a strong cough in one girl and after a workout in the other. Primary omental torsion usually mimics acute appendicitis with clinical findings in the right lower abdominal quadrant, especially in obese children. However, our two cases describe normosthenic girls with pain in the right upper abdominal quadrant up to the mesogastrium. CONCLUSION: Primary torsion of the omentum is a very rare cause of acute abdomen, which is also confirmed by its incidence in our group of patients where only two cases were seen during a 15-year period, which corresponds to 0.17% of all appendectomies performed in our department. This value is comparable to data reported in the literature. KEY WORDS: acute abdomen omental torsion tenderness in right upper abdomen.


Assuntos
Omento/diagnóstico por imagem , Doenças Peritoneais/diagnóstico por imagem , Anormalidade Torcional/diagnóstico por imagem , Abdome Agudo/etiologia , Pré-Escolar , Feminino , Humanos , Doenças Peritoneais/complicações , Tomografia Computadorizada por Raios X , Anormalidade Torcional/complicações
8.
Rozhl Chir ; 95(2): 69-77, 2016 Feb.
Artigo em Tcheco | MEDLINE | ID: mdl-27008168

RESUMO

INTRODUCTION: From the clinical point of view, rectal cancer and colon cancer are clearly different nosological units in their progress and treatment. The aim of this study was to analyse and clarify the differences between the behaviour of liver metastases from colon and rectal cancer. The study of these factors is important for determining an accurate prognosis and indication of the most effective surgical therapy and oncologic treatment of colon and rectal cancer as a systemic disease. METHOD: 223 patients with metastatic disease of colorectal carcinoma operated at the Department of Surgery, University Hospital in Pilsen between January 1, 2006 and January 31, 2012 were included in our study. The group of patients comprised 145 men (65%) and 117 women (35%). 275 operations were performed. Resection was done in 177 patients and radiofrequency ablation (RFA) in the total of 98 cases. Our sample was divided into 3 categories according to the location of the primary tumor to C (colon), comprising 58 patients, S (c. sigmoideum) in 61 patients, and R (rectum), comprising 101 patients. Significance analysis of the studied factors (age, gender, staging [TNM classification], grading, presence of mucinous carcinoma, type of operation) was performed using ANOVA test. Overall survival (OS), disease-free interval (DFI) or no evidence of disease (NED) were estimated using Kaplan-Meier curves, which were compared with the log-rank and Wilcoxon tests. RESULTS: As regards the comparison of primary origin of colorectal metastases in liver regardless of their treatment (resection and RFA), our study indicated that rectal liver metastases showed a significantly earlier recurrence than colon liver metastases (shorter NED/DFI). Among other factors, a locally advanced finding, further R2 resection of liver metastases and positivity of lymph node metastases were statistically significant for the prognosis of an early recurrence of the primary colon and sigmoid tumor. Furthermore, we proved that in patients with primary rectal carcinoma, DFI (after the resection of liver metastases) was not influenced by the positivity of lymph node metastases of primary tumor or locally advanced primary tumor. The other factors studied (time from diagnosis of organ metastases to primary operation, grading, sex or age) were not shown to be statistically significant for the prognosis of OS and DFI (colorectal cancer in total). CONCLUSION: As proven by our study, rectal cancer and colon cancer are two different nosological units with specific prognostic factors with respect to their liver metastases. These differences have not been fully understood yet and require further exploration and classification based not only on histopathological, immunohistochemical and clinical factors, but also on molecular biological parameters. KEY WORDS: colon carcinoma metastases rectal carcinoma metastases prognostic factors overall survival - liver metastases.


Assuntos
Carcinoma/cirurgia , Ablação por Cateter , Neoplasias do Colo/patologia , Neoplasias Hepáticas/cirurgia , Metastasectomia , Neoplasias Retais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/secundário , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
9.
Fogorv Sz ; 109(3): 94-101, 2016 Sep.
Artigo em Inglês, Húngaro | MEDLINE | ID: mdl-29693955

RESUMO

The Department of Oral Medicine at the University of Szeged was responsible for the stomato-oncological care of the population of three counties (with a population of 1,7 M at an average) in the period 1960-201 4. The present report summarizes the incidence of oral medicine diseases during this period. The overall number of new out-patients at the Department of Oral Surgery between 1960 and 2014 was 338,200. These patients were dental and oral surgical patients who presented spontaneously or were referred from the general practice, or stomato-oncological patients referred from general dental practices in-the three counties. Of the 338,200 new cases, 9,482 (2.8%) were benign tumors, 5438 (1.6%) premalignancies and 5,145 (1.5%) malignant tumors. This means a total of 20,065 tumor cases (5.9%) in the examined period, of which 10,579 (3.1 %) were premalignancies and malignancies. 14,446 patients presented with other diseases of the oral mucous membrane (5.8%, data available from 1974). Data on the number of stomato-oncological control patients in any given year are available from 1970 on. In the period 1970-2014, the total number of check-up patients was 117,268, this is the 76,97% of the departments overall number of patients. As for the tendencies, in the representative period of 1960-2004, the number of new benign tumors 15-fold, premalignancies 30-fold, and malignant tumors exhibited an 25-fold increase, while the number of other conditions affecting the oral mucosa showed a 14-fold increase.


Assuntos
Doenças da Boca/epidemiologia , Neoplasias Bucais/epidemiologia , Humanos , Hungria/epidemiologia , Programas de Rastreamento , Medicina Bucal , Estudos Retrospectivos , Fatores de Tempo , Universidades
10.
Rozhl Chir ; 94(5): 211-5, 2015 May.
Artigo em Tcheco | MEDLINE | ID: mdl-26112688

RESUMO

INTRODUCTION: In general, pain in the lower right abdomen is the most frequent reason for hospital surgical admissions, acute appendicitis representing the most common cause of operation for acute abdomen. Timely appendectomy remains the only treatment in the early stages of inflammation and is usually uncomplicated, requiring only a short hospital stay. A differential diagnostic analysis necessitates a search for other, particularly long-term symptoms that might be driven to the background in cases of acute exacerbation. CASE REPORT: The case report presents a 38-year-old female patient who was admitted for lower right abdominal pain. Clinical examination and a blood test both suggested typical acute uncomplicated appendicitis, and therefore the patient underwent appendectomy. Haemorrhagic peritoneal fluid and nodularity of the appendix not typical for appendicitis was found. Oedema of the terminal ileum and a right adnexal tumour were a surprising finding. A more extensive surgical procedure involving ileocaecal resection and right-side adnexectomy was finally performed with regard to the intraoperative finding. The definitive diagnosis of appendiceal endometriosis, endometrial mass in the terminal intestine and ovarian endometriosis was established by histological evaluation. Long-term follow-up revealed microadenocarcinoma of cervix uteri. CONCLUSION: It is generally very difficult to confirm appendiceal endometriosis before operation, and revealing primary appendiceal endometriosis is virtually impossible. It is advisable to consider endometriosis in fertile women with chronic abdominal pain of unclear aetiology and gynaecological symptoms in their personal history. The best diagnostic and therapeutic method, respectively, is laparoscopy enabling exploration of the entire peritoneal cavity including the minor pelvis, and performing appendectomy as well as excision of suspicious endometrial lesions. The definitive diagnosis is usually established by histopathological evaluation. Gynaecological assessment and follow-up is highly recommended after surgery.


Assuntos
Abdome Agudo/etiologia , Apendicectomia/métodos , Apendicite/diagnóstico , Endometriose/diagnóstico , Laparoscopia/métodos , Abdome Agudo/diagnóstico , Abdome Agudo/cirurgia , Doença Aguda , Adulto , Diagnóstico Diferencial , Endometriose/cirurgia , Feminino , Humanos
12.
Br Poult Sci ; 55(3): 375-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24730385

RESUMO

1. The aim of the study was to investigate the effect of melamine-contaminated feed (100 mg/kg) on the distribution of melamine and cyanuric acid in the tissues of laying hens. The effect of a 5-week melamine administration in feed on the egg quality and blood variables of layers was also investigated. 2. A total of twenty 36-week-old ISA Brown layers were used in the experiment. The layers were equally divided into an experimental melamine group (n = 10) and a control group without melamine (n = 10). At the end of the experiment, samples of liver, kidney, breast and thigh muscles were collected from all hens and analysed for the presence of melamine and cyanuric acid by gas chromatography and tandem mass spectrometry. 3. Layers receiving the melamine-contaminated diet laid eggs with decreased eggshell strength. The decrease in shell strength was found in weeks 3 and 4 compared to the initial state (week 0) and week 1. 4. Hens receiving the melamine-contaminated diet also exhibited a higher total red blood cell count and lower mean corpuscular haemoglobin compared to the control group. However, melamine at 100 mg/kg feed had no effects on the blood variables of layers. 5. Melamine was detected in all analysed tissues of layers fed on the melamine-contaminated diet, with its mean concentrations decreasing in the following order: kidney (7.43 mg/kg) > breast muscle (3.88 mg/kg) > liver (3.11 mg/kg) > thigh muscle (1.91 mg/kg). The kidney and liver of layers fed on the melamine-contaminated diet also exhibited the presence of cyanuric acid. 6. On the basis of our results, it can be concluded that the biotransformation of melamine into cyanuric acid proceeded mainly in the liver, and cyanuric acid was eliminated in urine.


Assuntos
Ração Animal , Galinhas/fisiologia , Triazinas/metabolismo , Triazinas/toxicidade , Animais , Biotransformação , Galinhas/crescimento & desenvolvimento , Casca de Ovo/efeitos dos fármacos , Casca de Ovo/fisiologia , Ovos , Contagem de Eritrócitos , Cromatografia Gasosa-Espectrometria de Massas , Fígado/metabolismo , Testes de Toxicidade
13.
Rozhl Chir ; 93(11): 549-53, 2014 Nov.
Artigo em Tcheco | MEDLINE | ID: mdl-25418943

RESUMO

INTRODUCTION: Cerebral salt wasting syndrome (CSWS) is one of several possible causes of the development of hyponatraemia in patients with severe cranial trauma associated with intracranial bleeding and brain oedema. Other possible causes of post-traumatic hyponatraemia include the syndrome of inappropriate antidiuretic hormone secretion (SIADH). CASE HISTORY: The authors present the case of a twenty-five-year-old polytraumatized female patient who was treated in our department and who was diagnosed with cerebral salt wasting syndrome. CONCLUSION: In patients with severe cranial trauma and subsequent hyponatraemia, CSWS should be considered. It is crucial to distinguish between CSWS and SIADH as wrongly selected treatment can have serious or even fatal impacts for a gravely injured patient.


Assuntos
Edema Encefálico/etiologia , Hiponatremia/etiologia , Síndrome de Secreção Inadequada de HAD/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Feminino , Humanos , Síndrome de Secreção Inadequada de HAD/complicações
14.
J Physiol Pharmacol ; 75(2): 215-222, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38736268

RESUMO

The analysis of volatile organic compounds (VOCs) present in various biological samples holds immense potential for non-invasive disease diagnostics and metabolic profiling. One of the biological fluids that are suitable for use in clinical practice is urine. Given the limited quantity of VOCs in the urine headspace, it's imperative to enhance their extraction into the gaseous phase and prevent any degradation of VOCs during the thawing process. The study aimed to test several key parameters (incubation time, temperature, and thawing) that can influence urine volatilome and monitor selected VOCs for their stability. The analysis in this study was performed using a BreathSpec® (G.A.S., Dortmund, Germany) device consisting of a gas chromatograph (GC) coupled with an ion mobility spectrometer (IMS). Testing three different temperatures and incubation times yielded a low number of VOCs (9 out of 34) that exhibited statistically significant differences. However, examining three thawing conditions revealed no VOCs with statistically significant changes. Thus, we conclude that urine composition remains relatively stable despite exposure to various thermal stresses.


Assuntos
Espectrometria de Mobilidade Iônica , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/urina , Compostos Orgânicos Voláteis/análise , Humanos , Projetos Piloto , Espectrometria de Mobilidade Iônica/métodos , Masculino , Adulto , Cromatografia Gasosa-Espectrometria de Massas/métodos , Feminino , Temperatura , Adulto Jovem , Pessoa de Meia-Idade
15.
Mar Pollut Bull ; 193: 115215, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37392593

RESUMO

This study evaluates PFAS contamination and determines the major drainage sources to a temperate microtidal estuary, the Swan Canning Estuary, in Perth Western Australia. We describe how variability in these sources influences PFAS concentrations within this urban estuary. Surface water samples were collected from 20 estuary sites and 32 catchment sites in June and December from 2016 to 2018. Modelled catchment discharge was used to estimate PFAS load over the study period. Three major catchment sources of elevated PFAS were identified with contamination likely resulting from historical AFFF use on a commercial airport and defence base. Estuary PFAS concentration and composition varied significantly with season and spatially with the two different estuary arms responding differently to winter and summer conditions. This study has found that the influence of multiple PFAS sources on an estuary depend on the historical usage timeframe, groundwater interactions and surface water discharge.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Água Subterrânea , Poluentes Químicos da Água , Estuários , Poluentes Químicos da Água/análise , Fluorocarbonos/análise , Água , Ácidos Alcanossulfônicos/análise
16.
J Physiol Pharmacol ; 74(2)2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37453098

RESUMO

Some studies have shown that electromagnetic fields (EMFs) may impact immune response cells and their functions. The first stage of the defense from pathogens is innate immunity encompassing phagocytosis and phagocytosis-related intracellular effects. Our work aimed to determine the influence of a low-frequency electromagnetic field (7 Hz, 30 mTrms) on the phagocytosis process of latex beads (LBs), the production of reactive oxygen species (ROS), and viability changes in a human monocytic Mono Mac 6 (MM6) cell line as an experimental model of the phagocytosing cells in in vitro cell culture conditions. For these purposes, cells were firstly activated with infectious agents such as lipopolysaccharide (LPS), Staphylococcal enterotoxin B (SEB), or the proliferatory agent phytohaemagglutinin (PHA), and then a phagocytosis test was performed. Cell viability and range of phagocytosis of latex beads by MM6 cells were measured by flow cytometry, and the level of ROS was evaluated with the use of a cytochrome C reduction test. The obtained results revealed that applied EMF exposure mainly increased the necrosis parameter of cell death when they were pre-stimulated with SEB as an infectious factor and subsequently phagocytosed LBs (P=0.001). Prestimulation with other agents like LPS or PHA preceding phagocytosis resulted in no statistically significant changes in cell death parameters. The level of ROS depended on the used stimulatory agent, phagocytosis, and/or EMF exposure. The obtained effects for EMF exposure indicated only a slight decrease in the ROS level for cells phagocytosing latex beads and being treated with SEB or PHA, while the opposite effect was observed for LPS pre-stimulated cells (data not statistically significant). The results concerning the viability of phagocytosing cells, the effectiveness of the phagocytosis process, and the level of radical forms might result from applied EMF parameters like signal waveform, frequency, flux density, and especially single EMF exposure.


Assuntos
Campos Eletromagnéticos , Lipopolissacarídeos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Microesferas , Lipopolissacarídeos/farmacologia , Fagocitose , Linhagem Celular
17.
Mutagenesis ; 27(2): 187-96, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22294766

RESUMO

Worldwide, colorectal cancer (CRC) is the third most common cancer, with the highest mortality rates occurring in Central Europe. The use of chemotherapy to treat CRC is limited by the inter-individual variability in drug response and the development of cancer cell resistance. ATP-binding cassette (ABC) transporters play a crucial role in the development of resistance by the efflux of anticancer agents outside of cancer cells. The aim of this study was to explore transcript levels of all human ABCs in tumours and non-neoplastic control tissues from CRC patients collected before the first line of treatment by 5-fluorouracil (5-FU)-containing regimen. The prognostic potential of ABCs was evaluated by the correlation of transcript levels with clinical factors. Relations between transcript levels of ABCs in tumours and chemotherapy efficacy were also addressed. The transcript profile of all known human ABCs was assessed using real-time polymerase chain reaction with a relative standard curve. The majority of the studied ABCs were down-regulated or unchanged between tumours and control tissues. ABCA12, ABCA13, ABCB6, ABCC1, ABCC2 and ABCE1 were up-regulated in tumours versus control tissues. Transcript levels of ABCA12, ABCC7 and ABCC8 increased in direction from colon to rectum. Additionally, transcript levels of ABCB9, ABCB11, ABCG5 and ABCG8 followed the reverse significant trend, i.e. a decrease in direction from colon to rectum. The transcript level of ABCC10 in tumours correlated with the grade (P = 0.01). Transcript levels of ABCC6, ABCC11, ABCF1 and ABCF2 were significantly lower in non-responders to palliative chemotherapy in comparison with responders. The disease-free interval of patients treated by adjuvant chemotherapy was significantly shorter in patients with low transcript levels of ABCA7, ABCA13, ABCB4, ABCC11 and ABCD4. In conclusion, ABCC11 may be a promising candidate marker for a validation study on 5-FU therapy outcome.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias Colorretais/genética , Idoso , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Quimioterapia Adjuvante , Colo/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Metástase Neoplásica , Projetos Piloto , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reto/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida
18.
Nature ; 441(7092): 486-8, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16724061

RESUMO

A material is said to exhibit dichroism if its photon absorption spectrum depends on the polarization of the incident radiation. In the case of X-ray magnetic circular dichroism (XMCD), the absorption cross-section of a ferromagnet or a paramagnet in a magnetic field changes when the helicity of a circularly polarized photon is reversed relative to the magnetization direction. Although similarities between X-ray absorption and electron energy-loss spectroscopy in a transmission electron microscope (TEM) have long been recognized, it has been assumed that extending such equivalence to circular dichroism would require the electron beam in the TEM to be spin-polarized. Recently, it was argued on theoretical grounds that this assumption is probably wrong. Here we report the direct experimental detection of magnetic circular dichroism in a TEM. We compare our measurements of electron energy-loss magnetic chiral dichroism (EMCD) with XMCD spectra obtained from the same specimen that, together with theoretical calculations, show that chiral atomic transitions in a specimen are accessible with inelastic electron scattering under particular scattering conditions. This finding could have important consequences for the study of magnetism on the nanometre and subnanometre scales, as EMCD offers the potential for such spatial resolution down to the nanometre scale while providing depth information--in contrast to X-ray methods, which are mainly surface-sensitive.

19.
Rozhl Chir ; 91(4): 219-29, 2012 Apr.
Artigo em Tcheco | MEDLINE | ID: mdl-22880270

RESUMO

INTRODUCTION: Colorectal anastomoses frequently become the site of of complications after surgical procedures for colorectal cancer. Anastomotic dehiscence has a significant impact on the whole p postoperative disease course, may influence the overal survival (OS) and disease free interval (DFI). The aim of our study was to analyze clinical and histopathological factors, that could facilitate detection of dehiscences and are related to the prognosis of patients. MATERIAL AND METHODS: The authors performed statistical analysis of a cohort of patients (340 pacients, 207 males, 133 females) who underwent radical resection followed by anastomosis on the large intestine during 2003-2007. The following factors were assessed: age, gender, staging, protective stoma, neoadjuvant chemotherapy, neoadjuvant radiotherapy, adjuvant chemotherapy, adjuvant radiotherapy and anastomotic insufficiency. Complications were evaluated according to Clavien and Dindo classification. RESULTS: The analysis confirmed the following factors to be statistically significant for prognosis of OS and DFI: In stage T4 subjects, the risk of death was 2.5 x higher and the risk of recurrence was 1.9 x higher than in the lower disease stage subjects. The presence of N2 lymph node metastases increases the risk of death 3.7 x and the risk of recurrence 3.6 x, compared to N0 and N1 cases. The presence of postoperative complications classified asf III.-V. grade according to Clavien and Dindo classification increases the risk of death 4x. The risk of death was 5.5 x higher in patients with dehiscence of anastomosis. The surprising finding was that even protective stoma increases the risk of death 5.4 x. Patients who did not undergo adjuvant chemotherapy were at 2 x higher risk of death. In patients with IIIA, IIIB, IV, V complications, the following factors proved to be statistically significant for prognosis of OS: leakage, protective stoma, adjuvant chemotherapy and adjuvant oncological treatment. In patients with complications I and II, the following factors were proved to be statistically significant for prognosis of OS: staging and lymph nodes metastases. Multivariate analysis CART confirmed significant correlation between the lymph nodes positivity and the Clavien and Dindo classification of complications. CONCLUSION: Analysis of clinical and histopathological factors is important for prediction of prognosis in patients with colorectal cancer after radical surgical treatment. Detection and application of these prognostic factors in postoperative period could influence the strategy of treatment and thus the overal survival in patients with radical resections for colorectal carcinoma. Nonadministration of adjutant chemotherapy results in a significant decrease in OS and DFI.


Assuntos
Neoplasias Colorretais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Fístula Anastomótica , Quimioterapia Adjuvante , Colectomia/efeitos adversos , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Colostomia , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Taxa de Sobrevida
20.
Arch Diabetes Obes ; 4(2): 403-415, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903156

RESUMO

Aims: To determine safety of intranasal insulin (INI) in MemAID trial participants with diabetes treated with systemic insulins. Materials and Methods: This randomized, double-blinded trial consisted of 24-week INI or placebo treatment once daily and 24-week follow-up. Safety outcomes were: 1) Short-term effects on glycemic variability, hypoglycemic episodes on continuous glucose monitoring (CGM) at baseline and on-treatment. 2) Long-term effects on glucose metabolism and weight on INI/placebo treatment and post-treatment follow-up. Of 86 screened subjects, 14 were randomized, 9 (5 INI, 4 Placebo) completed CGM at baseline and on-treatment, and 5 (2 INI, 3 Placebo) completed treatment and follow-up. Results: INI was safe and was not associated with serious adverse events, hypoglycemic episodes or weight gain. INI administration did not acutely affect capillary glucose. Glycemic variability on CGM decreased with INI, compared to baseline. On INI treatment, there was a long-term trend toward lower HbA1c, plasma glucose and insulin. No interactions with subcutaneous insulins were observed. Conclusions: INI is safe in older people with diabetes treated with systemic insulins, and it is not associated with adverse events, hypoglycemia or weight gain. Future studies are needed to determine whether INI administration can reduce glycemic variability, improve insulin sensitivity and thus potentially lessen diabetes burden in this population.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA