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1.
Rozhl Chir ; 101(8): 395-400, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36208935

RESUMO

INTRODUCTION: Endovenous laser ablation (EVLA) is a recognized alternative to surgical treatment of varicose veins, although an optimal laser generator and its settings still remain a matter of debate. The aim of our study was to correlate clinical results with the theoretical advantage of the 1940nm diode laser characterized by high absorption of heat in a thin layer of coagulated tissue. METHODS: From 1/2010 to 12/2021 EVLA was performed in a total of 3529 consecutive patients with varicose veins and ultrasonographically documented superficial venous reflux of lower extremities. Three types of laser were used successively with the wavelengths of 1064 nm, 1470 nm and 1940 nm, respectively. All patients were prospectively enrolled in our registry. An early postoperative followup visit was scheduled including an assessment of venous closure; additional visits were performed only in case of complications. RESULTS: The success of venous closure did not differ (p=0.054) between the three laser types and was over 98%. The catheterbased method made it possible to perform multiple ablations in one procedure the trend was 1.08, 1.31 and 1.62. In 2021 the number of ablations per patient with the laser DL Tethys 1940 nm was 1.79. With this laser it was possible to reduce the total energy applied to one half (8 W, 5080 J/cm). The postoperative course of patients treated using the 1940nm laser was smoother - no other but the early followup visit was needed in 95.6% cases (p.


Assuntos
Terapia a Laser , Varizes , Insuficiência Venosa , Humanos , Terapia a Laser/métodos , Lasers Semicondutores/uso terapêutico , Veia Safena/cirurgia , Resultado do Tratamento , Varizes/diagnóstico por imagem , Varizes/cirurgia , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/cirurgia
2.
Bratisl Lek Listy ; 122(5): 305-309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33848178

RESUMO

BACKGROUND: Diabetes mellitus (DM) and malignancy are recognized among the most common complications increasing mortality in patients after heart transplantation (HTx). Clinical trials have shown a higher risk for different types of tumours in diabetic patients. This risk is potentiated by immunosuppressive therapy in transplant patients. Biguanide metformin has been shown to exhibit anti-tumour activity and we tried to find out whether this effect is valid for heart transplant patients. METHODS: We retrospectively analysed a group of 497 patients, who undergone HTx in our centre between 1998 and 2019. The primary outcome was any malignancy during the 15-year follow-up period and patient's survival. RESULTS: Out of the 497 patients enrolled in the study, 279 (56 %) had diabetes and 52 (19 %) were treated with metformin. Fifteen-year survival in treated patients without malignancy was 93 %, the remainder for the DM patients was 56 %, with survival in non-DM patients being 74 %. Untreated diabetic patients had 4.7 times higher chance of malignancy than those on metformin (p = 0.01). Fifteen-year survival in metformin treated patients was 53 %, in other DM patients 44 %, and in non-DM patients 51 %. CONCLUSION: Our study showed a significantly lower incidence of malignancies in metformin-treated patients and slightly better overall survival (Tab. 2, Fig. 3, Ref. 19) Keywords: biguanide, heart graft, malignancy, diabetes mellitus, survival.


Assuntos
Transplante de Coração , Metformina , Neoplasias , Transplante de Coração/efeitos adversos , Humanos , Hipoglicemiantes/efeitos adversos , Metformina/efeitos adversos , Neoplasias/epidemiologia , Estudos Retrospectivos
3.
Plants (Basel) ; 9(12)2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33276523

RESUMO

Previously, studies on RING-type E3 ubiquitin ligases in cereals were preferentially focused on GW2 genes primarily controlling seed parameters in rice and wheat. Here we report cloning two HvYrg genes from barley that share significant homology with rice GW2 gene. In antisense genotypes efficiency of gene silencing varied between genes and transgenic lines: ASHvYrg1: 30-50% and ASHvYrg2: 20-27%. Reduced activity of both genes altered shoot system with increasing number of side shoots. Changes in leaf width, weight, or plant weight and height reached significant levels in some transgenic lines. Lowering expression of the two barley HvYrg genes caused opposite responses in spike development. Plants with ASHvYrg1 gene construct showed earlier heading time and prolonged grain-filling period, while plants from ASHvYrg2 genotype flowered in delay. Digital imaging of root development revealed that down-regulation of HvYrg1 gene variant stimulated root growth, while ASHvYrg2 plants developed reduced root system. Comparison of seed parameters indicated an increase in thousand grain weight accompanied with longer and wider seed morphology. In summary we conclude that in contrast to inhibition of GW2 genes in rice and wheat plants, down-regulation of the barely HvYrg genes caused substantial changes in vegetative organs in addition to alteration of seed parameters.

4.
Rozhl Chir ; 99(7): 299-303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32972147

RESUMO

INTRODUCTION: Endovenous Laser Ablation (EVLA) is a common alternative to surgical treatment of varicose veins. The aim of our study was to demonstrate that laser occlusion is durable, that we can treat all patients in a one day setting, even with veins >10mm in diameter, and that multiple EVLAs can be done at the same time. METHODS: In the period from 1/2017 to 12/2019 EVLA was performed in a total of 1551 consecutive patients with varicose veins and ultrasonographically documented venous reflux. The mid-term results were evaluated in a group of patients operated from 1/2017 to 6/2017 (316 pts.). We compared a risk group that consisted of patients with veins >10mm in diameter (40 pts.) with a control group (the remaining 276 pts.). Patients with veins >10mm are traditionally considered as candidates for conventional surgery. RESULTS: The catheter-based method enabled us to perform more ablations in one procedure. In 2019 we performed 1.44 EVLA procedures per patient. There was only one postoperative follow-up visit, indicating an uncomplicated postoperative course, in 87.5% of patients of the risk group. In the control group 100% of patients had only one follow-up visit including ultrasound examination, showing an uncomplicated postoperative course (p.


Assuntos
Terapia a Laser , Varizes/diagnóstico por imagem , Varizes/cirurgia , Insuficiência Venosa , Humanos , Veia Safena/diagnóstico por imagem , Veia Safena/cirurgia , Resultado do Tratamento
5.
Rozhl Chir ; 98(6): 248-251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31331181

RESUMO

INTRODUCTION: Catheter-Based Endovenous Laser Ablation (EVLA) is a commonly used alternative to surgical treatment of varicose veins. Recently, catheterization methods have proved to be methods of choice due to the preference of patients who value minimal invasiveness. Research of EVLA currently focuses on optimization of the procedure, which includes study of the benefits of the individual types of laser generators and the wavelengths used. In this observational study we compared our early results in a non-selected population of consecutive patients treated with two different types of lasers. METHODS: In the period from February 2010 to June 2017, EVLA was performed in a total of 1747 consecutive patients (74% were female) with venous reflux. The average vein width was 8.5 mm (525 mm). Our study sought to compare a more economical 1470nm diode laser (DL) generator (Velas 2, China) - used to operate on 630 patients - with a Nd-Yag crystal generator (Fotona - Slovenia) used in 1117 patients. All operations were performed using the same methodology, in an outpatient setting, in one specialized center. All procedures were completed in local tumescent anesthesia under peroperative ultrasound control. Postoperative sonography was performed in all patients. RESULTS: The results did not show a statistically significant difference in early closure rates (98.8% for Nd-Yag versus 99.8 for DL p-ns). Early recurrence was observed in 9 patients (15 vein segments) and managed successfully with early re-intervention and closure in all cases. The causes of incomplete closure included mainly the known risk factors (anticoagulation therapy, history of varicophlebitis). There was no correlation with larger venous diameter. In 6 patients, thrombus prolapse was observed in the deep femoral vein lumen. All cases were successfully cured after a week of low-molecular-weight heparin therapy. Only one case of low-risk pulmonary embolism was reported in a patient who failed to follow the regime recommendations. CONCLUSION: This evidence did not show a significant difference in closure reliability and the amount of complications of the endovenous laser ablation of large and small saphenous vein with a 1060nm Nd-Yag crystal compared to the more economical 1470nm diode laser generator.


Assuntos
Ablação por Cateter , Terapia a Laser , Varizes , Insuficiência Venosa , Feminino , Humanos , Extremidade Inferior , Masculino , Reprodutibilidade dos Testes , Veia Safena , Resultado do Tratamento , Varizes/terapia , Insuficiência Venosa/terapia
6.
Bratisl Lek Listy ; 118(6): 366-369, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28664747

RESUMO

BACKGROUND: A strong correlation between a lower heart rate and survival has been demonstrated in various patient populations. The optimal heart rate for heart transplant patients is still unknown. The aim of our study was to evaluate the association between an early heart rate and survival after heart transplantation. MATERIAL AND METHODS: We retrospectively analysed a group of 330 patients, who underwent heart transplantation in our institution from 1994 to 2014 and complete datasets, including 24-hour heart rate monitoring one month after the heart transplantation. Patients were divided in 2 groups: Group A (n = 278) with the average 24-hour heart rate <90 bpm, and Group B (n = 52) with ≥ 90 bpm. RESULTS: The average period of monitoring was 7.5 ± 5.3 years. No differences in baseline characteristics were observed in both groups of recipients and respective donors. One-year survival in groups A and B was 92 % and 81 %, respectively; 5-year survival was 79 % and 60 %, respectively; and 10-year survival was 66 % and 50 %, respectively (p = 0.001). CONCLUSION: Increased heart rate in the early post-transplant period was significantly associated with a poorer survival rate in patients after heart transplantation (Tab. 2, Fig. 1, Ref. 25).


Assuntos
Cardiopatias/cirurgia , Frequência Cardíaca , Transplante de Coração , Taxa de Sobrevida , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Doadores de Tecidos , Adulto Jovem
7.
J Thromb Haemost ; 15(8): 1625-1639, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28509332

RESUMO

Essentials Tissue factor (TF) represents a central link between hemostasis and inflammation. We studied the roles of myeloid and airway epithelial TF in acid-caused acute lung injury (ALI). TF on myeloid cells displays a non-coagulatory role regulating the inflammatory response in ALI. Airway epithelial TF contributes to hemostatic functions, but is dispensable in ALI pathogenesis. SUMMARY: Introduction Acute lung injury (ALI) is a life-threatening condition characterized by damaged alveolar-capillary structures and activation of inflammatory and hemostatic processes. Tissue factor (TF) represents a crucial link between inflammation and coagulation, as inflammatory mediators induce myeloid TF expression, and TF initiates extrinsic coagulation. Objective As pulmonary inflammation stimulates TF expression and TF modulates immune responses, we aimed to elucidate its impact on ALI. In particular, we wanted to distinguish the contributions of TF expressed on airway epithelial cells and TF expressed on myeloid cells. Methods Mice with different cell type-specific TF deficiency and wild-type littermates were intratracheally treated with hydrochloric acid, and leukocyte recruitment, cytokine levels, thrombin-antithrombin (TAT) complexes and pulmonary protein-rich infiltrates were analyzed. Results Our data demonstrate that a lack of epithelial TF did not influence acute responses, as bronchoalveolar neutrophil accumulation 8 h after ALI induction was unaltered. However, it led to mild, prolonged inflammation, as pulmonary leukocyte and erythrocyte numbers were still increased after 24 h, whereas those in wild-type mice had returned to basal levels. In contrast, myeloid TF was primarily involved in regulating the acute phase of ALI without affecting local coagulation, as indicated by increased bronchoalveolar neutrophil infiltration, pulmonary interleukin-6 levels, and edema formation, but equal TAT complex formation, 8 h after ALI induction. This augmented inflammatory response associated with myeloid TF deficiency was confirmed in vitro, as lipopolysaccharide-stimulated TF-deficient alveolar macrophages released increased levels of chemokine (C-X-C motif) ligand 1 and tumor necrosis factor-α as compared with wild-type macrophages. Conclusion We conclude that myeloid TF dampens inflammation in acid-induced ALI.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Células Epiteliais/metabolismo , Ácido Clorídrico , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Pneumonia/prevenção & controle , Tromboplastina/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/metabolismo , Animais , Antitrombina III/metabolismo , Coagulação Sanguínea , Células Cultivadas , Quimiotaxia de Leucócito , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/imunologia , Predisposição Genética para Doença , Mediadores da Inflamação/metabolismo , Pulmão/imunologia , Macrófagos Alveolares/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos , Peptídeo Hidrolases/metabolismo , Fenótipo , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Pneumonia/metabolismo , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/metabolismo , Edema Pulmonar/prevenção & controle , Tromboplastina/deficiência , Tromboplastina/genética , Fatores de Tempo
8.
Adv Water Resour ; 63: 120-130, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24821993

RESUMO

Drinking water wells indiscriminatingly placed adjacent to fecal contaminated surface water represents a significant but difficult to quantify health risk. Here we seek to understand mechanisms that limit the contamination extent by scaling up bacterial transport results from the laboratory to the field in a well constrained setting. Three pulses of E. coli originating during the early monsoon from a freshly excavated pond receiving latrine effluent in Bangladesh were monitored in 6 wells and modeled with a two-dimensional (2-D) flow and transport model conditioned with measured hydraulic heads. The modeling was performed assuming three different modes of interaction of E. coli with aquifer sands: 1) irreversible attachment only (best-fit ki=7.6 day-1); 2) reversible attachment only (ka=10.5 and kd=0.2 day-1); and 3) a combination of reversible and irreversible modes of attachment (ka=60, kd=7.6, ki=5.2 day-1). Only the third approach adequately reproduced the observed temporal and spatial distribution of E. coli, including a 4-log10 lateral removal distance of ∼9 m. In saturated column experiments, carried out using aquifer sand from the field site, a combination of reversible and irreversible attachment was also required to reproduce the observed breakthrough curves and E. coli retention profiles within the laboratory columns. Applying the laboratory-measured kinetic parameters to the 2-D calibrated flow model of the field site underestimates the observed 4-log10 lateral removal distance by less than a factor of two. This is promising for predicting field scale transport from laboratory experiments.

9.
Acta Biol Hung ; 64(2): 262-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23739893

RESUMO

A new, rapid method is described which permits the genotyping of genetically modified animals from a microlitre volume of whole blood samples via one step polymerase chain reaction amplification. The major advantage of the presented method is the exclusion of a DNA preparation step, which significantly reduces the time expenditure and work load of the genetic testing. Pilot studies indicate, that this method is efficient and applicable also on tissue biopsies and larger amount of blood providing a rapid and reliable new technique over conventional genotyping approaches.


Assuntos
Sangue , DNA , Técnicas de Genotipagem/métodos , Reação em Cadeia da Polimerase/métodos , Animais , DNA/química , DNA/genética , Camundongos , Camundongos Knockout
10.
Neuroscience ; 201: 320-30, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22108615

RESUMO

In situ hybridization, quantitative reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot analysis were applied to study the changes in expression of the major nociceptive ion channel transient receptor potential vanilloid type 1 receptor (TRPV1) after the perineural application of capsaicin or nerve transection. In control rats, quantitative morphometric and statistical analyses of TRPV1 protein and mRNA expression in L5 dorsal root ganglion cells revealed distinct populations of small (type C) and small-to-medium (type B) neurons, which showed very high and moderate levels of TRPV1, whereas larger (type A) neurons mostly did not express this receptor. After either transection or capsaicin treatment of the sciatic nerve, immunohistochemistry and Western blotting demonstrated a massive (up to 80%) decrease in the proportion of TRPV1-immunoreactive neurons and TRPV1 protein at all postoperative survival times. In situ hybridization indicated marked decreases (up to 85%) in the proportion of neurons that expressed TRPV1 mRNA after sciatic nerve transection. In contrast, although perineural treatment with capsaicin resulted in similar substantial decreases in the proportions of type B and C neurons of the L5 dorsal root ganglia 3 days postoperatively, a clear-cut tendency to recovery was observed thereafter. Hence, the proportions of both type B and C neurons expressing TRPV1 mRNA reached up to 70% of the control levels at 30 days postoperatively. In accord with these findings, quantitative RT-PCR revealed a marked and significant recovery in TRPV1 mRNA after perineural capsaicin but not after nerve transection. These observations suggest the involvement of distinct cellular mechanisms in the regulation of the TRPV1 mRNA expression of damaged neurons, specifically triggered by the nature of the injury. The present findings imply that the antinociceptive and anti-inflammatory effects of perineurally applied capsaicin involve distinct changes in neuronal TRPV1 mRNA expression and long-lasting alterations in (post)translational regulation.


Assuntos
Gânglios Espinais/patologia , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Neuropatia Ciática/patologia , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Análise de Variância , Animais , Capsaicina/efeitos adversos , Contagem de Células , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Neuropatia Ciática/induzido quimicamente , Neuropatia Ciática/etiologia , Fármacos do Sistema Sensorial/efeitos adversos , Fatores de Tempo
11.
Cell Prolif ; 41(6): 875-893, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19040567

RESUMO

OBJECTIVES: This article is to study the role of G(1)/S regulators in differentiation of pluripotent embryonic cells. MATERIALS AND METHODS: We established a P19 embryonal carcinoma cell-based experimental system, which profits from two similar differentiation protocols producing endodermal or neuroectodermal lineages. The levels, mutual interactions, activities, and localization of G(1)/S regulators were analysed with respect to growth and differentiation parameters of the cells. RESULTS AND CONCLUSIONS: We demonstrate that proliferation parameters of differentiating cells correlate with the activity and structure of cyclin A/E-CDK2 but not of cyclin D-CDK4/6-p27 complexes. In an exponentially growing P19 cell population, the cyclin D1-CDK4 complex is detected, which is replaced by cyclin D2/3-CDK4/6-p27 complex following density arrest. During endodermal differentiation kinase-inactive cyclin D2/D3-CDK4-p27 complexes are formed. Neural differentiation specifically induces cyclin D1 at the expense of cyclin D3 and results in predominant formation of cyclin D1/D2-CDK4-p27 complexes. Differentiation is accompanied by cytoplasmic accumulation of cyclin Ds and CDK4/6, which in neural cells are associated with neural outgrowths. Most phenomena found here can be reproduced in mouse embryonic stem cells. In summary, our data demonstrate (i) that individual cyclin D isoforms are utilized in cells lineage specifically, (ii) that fundamental difference in the function of CDK4 and CDK6 exists, and (iii) that cyclin D-CDK4/6 complexes function in the cytoplasm of differentiated cells. Our study unravels another level of complexity in G(1)/S transition-regulating machinery in early embryonic cells.


Assuntos
Diferenciação Celular , Linhagem da Célula , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Ciclinas/metabolismo , Embrião de Mamíferos/citologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Ciclina A/metabolismo , Ciclina D , Ciclina E/metabolismo , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Fase G1 , Humanos , Espaço Intracelular/metabolismo , Camundongos , Modelos Biológicos , Ligação Proteica , Transporte Proteico , Fase S
12.
Folia Biol (Praha) ; 53(5): 157-63, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17976305

RESUMO

LIF is a cytokine playing a key role in the regulation of self-renewal and maintenance of undifferentiated state in mouse ES cells. The response of pluripotent cells to LIF is mediated mainly by the STAT3 and ERK signalling pathways. Recently, we have shown that LIF potentiated retinoic acid-induced neural differentiation of pluripotent mouse embryonal carcinoma P19 cells. Here we demonstrate that pro-neural effects of LIF and partially also of retinoic acid are abolished by inhibition of the JAK2->STAT3 signalling pathway. In contrast, inhibition of the MEK1->ERK signalling pathway does not exhibit any effect. These results suggest that in neurogenic regions, cooperative action of LIF and other neuro-differentiation-inducing factors, such as retinoic acid, may be mediated by the STAT3 signalling pathway.


Assuntos
Carcinoma Embrionário/patologia , Diferenciação Celular/efeitos dos fármacos , Fator Inibidor de Leucemia/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Butadienos/farmacologia , Carcinoma Embrionário/enzimologia , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Janus Quinase 2/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Nitrilas/farmacologia , Elementos de Resposta , Fator de Transcrição STAT3/genética , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Tretinoína/farmacologia , Tirfostinas/farmacologia
13.
J Orthop Surg (Hong Kong) ; 15(1): 4-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17429108

RESUMO

PURPOSE: To analyse the functional and radiological outcomes of the Bristow-Latarjet procedure in patients with recurrent anterior glenohumeral instability. METHODS: Records of 29 patients were reviewed retrospectively. Date of first dislocation, injury mechanism, and number of recurring dislocations before and after surgery were recorded. The overall function and stability of the shoulder was evaluated. RESULTS: 24 (83%) of the glenohumeral instabilities were caused by trauma. The mean number of recurring dislocations was 8 (95% confidence interval [CI], 0-18); one patient had had 40 recurrences. No dislocation ensued postoperatively. The overall functional outcome was good, with a mean Rowe score of 90 points (95% CI, 78-100). Scores of 17 (59%) of the patients were excellent, 7 (24%) were good, 3 (10%) were fair, and 2 (7%) were poor. CONCLUSION: The Bristow-Latarjet procedure is a good surgical treatment for recurrent anterior-inferior instability of the glenohumeral joint.


Assuntos
Instabilidade Articular/cirurgia , Procedimentos Ortopédicos , Articulação do Ombro , Adolescente , Adulto , Feminino , Humanos , Instabilidade Articular/fisiopatologia , Masculino , Amplitude de Movimento Articular
14.
Anal Chim Acta ; 591(1): 17-21, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17456419

RESUMO

Molecularly imprinted polymers (MIP) have been successfully synthesized toward many different compounds in the last decades. The mechanistic details of selective binding at binding sites are not yet well understood. For this reason the characterization of MIP binding has been mostly phenomenological and this makes the transfer of results between different laboratories or between different types of applications difficult. In this paper we analyze the relationship between different types of characterization like isotherms, binding site models, chromatographic k and alpha values, etc. as they relate to different applications like HPLC, solid phase extraction (SPE), binding assays, batch extraction and sensors. It is shown that alpha values determined by elution chromatography depend on seemingly irrelevant factors as the length and diameter of the column, respectively. The determination of distribution ratios or partition coefficients is proposed as an easily understandable and useful quantity in the characterization of novel MIPs. Data used for the characterization of a MIP should be transferable between different applications but the qualification of MIPs as better or worse will depend on the application in case.

15.
Neoplasma ; 54(2): 127-30, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17319785

RESUMO

Ovarian carcinoma is the leading cause of death among gynecological neoplasms in the world. The chemoresistance is a major obstacle in the effective treatment of ovarian and other cancers. We evaluated the effects of Hsp90 inhibitor geldanamycin (GEL) alone and in combination with cisplatin in cisplatin resistant ovarian adenocarcinoma cell line. Our results showed Akt depletion and S-phase arrest of A2780cis cells after GEL treatment. Combined exposure of A2780cis cells to GEL and cisplatin resulted in greater than additive cytotoxic effect.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas/efeitos dos fármacos
16.
J Chromatogr A ; 1119(1-2): 29-33, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16300772

RESUMO

Molecularly imprinted polymers (MIPs) have frequently been characterized by quantities which are easily determined from experiments but have no theoretical foundation. This makes it difficult to compare different MIP preparations or to transfer MIP based methods to different experimental conditions. Since the adsorption isotherms of MIPs are markedly nonlinear, one can build a better characterization strategy on isotherms as shown by examples in this paper.


Assuntos
Polímeros/química , Adsorção , Sítios de Ligação , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fenilalanina/análogos & derivados , Fenilalanina/isolamento & purificação , Fenitoína/isolamento & purificação , Temperatura , Timina/isolamento & purificação
17.
Cell Mol Life Sci ; 61(11): 1384-400, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15170516

RESUMO

In mouse embryonic stem (mES) cells, the expression of p27 is elevated when differentiation is induced. Using mES cells lacking p27 we tested the importance of p27 for the regulation of three critical cellular processes: proliferation, differentiation, and apoptosis. Although cell cycle distribution, DNA synthesis, and the activity of key G1/S-regulating cyclin-dependent kinases remained unaltered in p27-deficient ES cells during retinoic acid-induced differentiation, the amounts of cyclin D2 and D3 in such cells were much lower compared with normal mES cells. The onset of differentiation induces apoptosis in p27-deficient cells, the extent of which can be reduced by artificially increasing the level of cyclin D3. We suggest that the role of p27 in at least some differentiation pathways of mES cells is to prevent apoptosis, and that it is not involved in slowing cell cycle progression. We also propose that the pro-survival function of p27 is realized via regulation of metabolism of D-type cyclin(s).


Assuntos
Apoptose , Proteínas de Ciclo Celular/fisiologia , Células-Tronco/citologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Diferenciação Celular , Divisão Celular , Ciclina D2 , Ciclina D3 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/análise , Ciclinas/metabolismo , Embrião de Mamíferos/citologia , Interfase , Camundongos , Camundongos Knockout , Tretinoína , Proteínas Supressoras de Tumor/deficiência
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(5 Pt 1): 051103, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14682784

RESUMO

We report experimental results for the behavior of slow-combustion fronts in the presence of a columnar defect with enhanced or reduced driving, and compare them with those of mean-field theory. We also compare them with simulation results for an analogous problem of driven flow of particles with hard-core repulsion (ASEP) and a single defect bond with a different hopping probability. The difference in the shape of the front profiles for enhanced vs reduced driving in the defect clearly demonstrates the existence of a Kardar-Parisi-Zhang-type nonlinear term in the effective evolution equation for the slow-combustion fronts. We also find that slow-combustion fronts display a faceted form for large enough enhanced driving, and that there is a corresponding increase then in the average front speed. This increase in the average front speed disappears at a nonzero enhanced driving in agreement with the simulated behavior of the ASEP model.

19.
Toxicol In Vitro ; 17(4): 457-63, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12849729

RESUMO

9-Bromo-5-morpholino-tetrazolo[1,5-c]quinazoline (BMTQ) acted cytotoxically on murine leukemia cell line L1210 and human colon carcinoma cells Caco-2. We found the two highest concentrations of BMTQ (149.2 and 74.6 microM) induced an acute cytotoxic effect, however other tested concentrations (<74.6 microM) manifested a concentration/dependent and time/dependent cytotoxic effect. The sensitivity of murine leukemia cells L1210 and human colon carcinoma cells Caco-2 was expressed in the same order. The cytotoxicity of BMTQ was not accompanied by changes of the cell cycle profile. Following the cytotoxicity-related effects of BMTQ we observed the induction of ssDNA breaks after BMTQ treatment. All the concentrations of BMTQ increased the level of ssDNA breaks 1.3-2.9 times (after 2 h of treatment) and 1.6-2.8 times (after 4 h of treatment) in Caco-2 cells compared to the control. No apoptotic DNA fragmentation induced by BMTQ in Caco-2 cells was recorded.


Assuntos
Antineoplásicos/toxicidade , DNA de Cadeia Simples/efeitos dos fármacos , Quinazolinas/toxicidade , Tetrazóis/toxicidade , Animais , Apoptose/efeitos dos fármacos , Células CACO-2 , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Humanos , Leucemia L1210/tratamento farmacológico , Camundongos , Células Tumorais Cultivadas
20.
J Chromatogr A ; 930(1-2): 31-8, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11681577

RESUMO

A molecularly imprinted polymer (MIP) using phenytoin as template and methacrylamide as the functional monomer was prepared. The selectivity was measured by comparing capacity factors of phenytoin and other structurally related compounds. The polymer was evaluated as a selective sorbent in molecularly imprinted solid-phase extraction (MISPE). Several washing solvents were tested to study their ability to disrupt the non-specific interactions occurring between the sample and the polymer matrix and the role of water in the recognition process was also investigated. It was shown that the key step of successful sample extraction is the right choice of the washing solvent. Plasma samples spiked with phenytoin were analyzed by the MISPE methodology developed in this work. Method validation (intra- and inter-day precision, recovery, specificity) was carried out. The calibration curve showed good linearity in the 2.5-40 microg/ml range corresponding to therapeutically relevant plasma levels. The intra- and inter-day precision values were below the 15% limit established for bioanalytical methods. The results showed that the method could be successfully applied for the determination of phenytoin in plasma samples.


Assuntos
Anticonvulsivantes/sangue , Fenitoína/sangue , Calibragem , Humanos , Polímeros , Padrões de Referência , Reprodutibilidade dos Testes
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