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1.
Opt Express ; 20(18): 20742-7, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037123

RESUMO

We present the setup of a polarization rotating device and its adaption for high-power short-pulse laser systems. Compared to conventional halfwave plates, the all-reflective principle using three zero-phase shift mirrors provides a higher accuracy and a higher damage threshold. Since plan-parallel plates, e.g. these halfwave plates, generate postpulses, which could lead to the generation of prepulses during the subsequent laser chain, the presented device avoids parasitic pulses and is therefore the preferable alternative for high-contrast applications. Moreover the device is easily scalable for large beam diameters and its spectral reflectivity can be adjusted by an appropriate mirror coating to be well suited for ultra-short laser pulses.


Assuntos
Lasers de Estado Sólido , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
2.
Diabetologia ; 54(8): 2132-42, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21562757

RESUMO

AIMS/HYPOTHESIS: Obesity is strongly associated with the development of non-alcoholic fatty liver disease (NAFLD). The cytokine osteopontin (OPN) was recently shown to be involved in obesity-induced adipose tissue inflammation and reduced insulin response. Accumulating evidence links OPN to the pathogenesis of NAFLD. Here we aimed to identify the role of OPN in obesity-associated hepatic steatosis and impaired hepatic glucose metabolism. METHODS: Wild-type (WT) and Opn (also known as Spp1) knockout (Opn (-/-)) mice were fed a high-fat or low-fat diet to study OPN effects in obesity-driven hepatic alterations. RESULTS: We show that genetic OPN deficiency protected from obesity-induced hepatic steatosis, at least in part, by downregulating hepatic triacylglycerol synthesis. Conversely, absence of OPN promoted fat storage in adipose tissue thereby preventing the obesity-induced shift to ectopic fat accumulation in the liver. Euglycaemic-hyperinsulinaemic clamp studies revealed that insulin resistance and excess hepatic glucose production in obesity were significantly attenuated in Opn (-/-) mice. OPN deficiency markedly improved hepatic insulin signalling as shown by enhanced insulin receptor substrate-2 phosphorylation and prevented upregulation of the major hepatic transcription factor Forkhead box O1 and its gluconeogenic target genes. In addition, obesity-driven hepatic inflammation and macrophage accumulation was blocked by OPN deficiency. CONCLUSIONS/INTERPRETATION: Our data strongly emphasise OPN as mediator of obesity-associated hepatic alterations including steatosis, inflammation, insulin resistance and excess gluconeogenesis. Targeting OPN action could therefore provide a novel therapeutic strategy to prevent obesity-related complications such as NAFLD and type 2 diabetes.


Assuntos
Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Glucose/metabolismo , Obesidade/complicações , Obesidade/fisiopatologia , Osteopontina/deficiência , Animais , Técnica Clamp de Glucose , Immunoblotting , Imuno-Histoquímica , Imunoprecipitação , Masculino , Camundongos , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Osteopontina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/metabolismo
3.
Diabet Med ; 28(5): 549-59, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21480966

RESUMO

AIMS: The aim of this study was to compare the effects of calorie-restricted vegetarian and conventional diabetic diets alone and in combination with exercise on insulin resistance, visceral fat and oxidative stress markers in subjects with Type 2 diabetes. METHODS: A 24-week, randomized, open, parallel design was used. Seventy-four patients with Type 2 diabetes were randomly assigned to either the experimental group (n = 37), which received a vegetarian diet, or the control group (n = 37), which received a conventional diabetic diet. Both diets were isocaloric, calorie restricted (-500 kcal/day). All meals during the study were provided. The second 12 weeks of the diet were combined with aerobic exercise. Participants were examined at baseline, 12 weeks and 24 weeks. Primary outcomes were: insulin sensitivity measured by hyperinsulinaemic isoglycaemic clamp; volume of visceral and subcutaneous fat measured by magnetic resonance imaging; and oxidative stress measured by thiobarbituric acid reactive substances. Analyses were by intention to treat. RESULTS: Forty-three per cent of participants in the experimental group and 5% of participants in the control group reduced diabetes medication (P < 0.001). Body weight decreased more in the experimental group than in the control group [-6.2 kg (95% CI -6.6 to -5.3) vs. -3.2 kg (95% CI -3.7 to -2.5); interaction group × time P = 0.001]. An increase in insulin sensitivity was significantly greater in the experimental group than in the control group [30% (95% CI 24.5-39) vs. 20% (95% CI 14-25), P = 0.04]. A reduction in both visceral and subcutaneous fat was greater in the experimental group than in the control group (P = 0.007 and P = 0.02, respectively). Plasma adiponectin increased (P = 0.02) and leptin decreased (P = 0.02) in the experimental group, with no change in the control group. Vitamin C, superoxide dismutase and reduced glutathione increased in the experimental group (P = 0.002, P < 0.001 and P = 0.02, respectively). Differences between groups were greater after the addition of exercise training. Changes in insulin sensitivity and enzymatic oxidative stress markers correlated with changes in visceral fat. CONCLUSIONS: A calorie-restricted vegetarian diet had greater capacity to improve insulin sensitivity compared with a conventional diabetic diet over 24 weeks. The greater loss of visceral fat and improvements in plasma concentrations of adipokines and oxidative stress markers with this diet may be responsible for the reduction of insulin resistance. The addition of exercise training further augmented the improved outcomes with the vegetarian diet.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Dieta Vegetariana , Hemoglobinas Glicadas/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Resultado do Tratamento
4.
Histochem Cell Biol ; 133(6): 607-26, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20443021

RESUMO

Actin is a well-known protein that has shown a myriad of activities in the cytoplasm. However, recent findings of actin involvement in nuclear processes are overwhelming. Actin complexes in the nucleus range from very dynamic chromatin-remodeling complexes to structural elements of the matrix with single partners known as actin-binding proteins (ABPs). This review summarizes the recent findings of actin-containing complexes in the nucleus. Particular attention is given to key processes like chromatin remodeling, transcription, DNA replication, nucleocytoplasmic transport and to actin roles in nuclear architecture. Understanding the mechanisms involving ABPs will definitely lead us to the principles of the regulation of gene expression performed via concerting nuclear and cytoplasmic processes.


Assuntos
Actinas/metabolismo , Núcleo Celular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Actinas/química , Animais , Núcleo Celular/química , Reparo do DNA , Replicação do DNA , Humanos , Proteínas dos Microfilamentos/química , Modelos Biológicos
5.
Peptides ; 125: 170176, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31669136

RESUMO

BACKGROUND, AIMS: In patients with type 2 diabetes, the lost insulinotropic effect of the incretin hormone glucose-dependent insulinotropic polypeptide (GIP) is more apparent after continuous versus bolus administration. To test whether the difference might be explained by rapid tachyphylaxis in response to elevated concentrations of GIP, and whether patients with type 2 diabetes and their relatives are more susceptible to tachyphylaxis than healthy subjects. PATIENTS AND METHODS: In a two-way crossover design, insulinotropic responses to repeated bolus injection (50 pmol/kg body weight at 30 and 120 min) and continuous infusion of GIP (2 pmol.kg-1.min-1 from 30 to 180 min) under hyperglycaemic clamp conditions (8.5 mmol/l) was compared in age- gender- and weight-matched patients with type 2 diabetes, first degree relatives of such patients, and healthy subjects. RESULTS: Insulin secretory responses to the first and second GIP bolus were not significantly different in any of the subject groups. Subjects with type 2 diabetes had a significant relative impairment versus healthy subjects with continuous (C-peptide, -13.2 %, p < 0.05), but not with repeated bolus administration of GIP (+11.1 %, n.s.). First-degree relatives tended to hyper-secrete insulin with bolus or continuous administrations of GIP. CONCLUSIONS: Rapid tachyphylaxis in response to continuous exposure to slightly supraphysiological concentrations of GIP does not explain the reduced insulinotropic response to GIP infusions in patients with type 2 diabetes or their first-degree relatives.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Polipeptídeo Inibidor Gástrico/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Secreção de Insulina , Receptores dos Hormônios Gastrointestinais/metabolismo , Taquifilaxia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Polipeptídeo Inibidor Gástrico/sangue , Fármacos Gastrointestinais/sangue , Humanos , Masculino , Pessoa de Meia-Idade
6.
Mol Metab ; 4(1): 39-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25685688

RESUMO

OBJECTIVE: Excess lipid intake has been implicated in the pathophysiology of hepatosteatosis and hepatic insulin resistance. Lipids constitute approximately 50% of the cell membrane mass, define membrane properties, and create microenvironments for membrane-proteins. In this study we aimed to resolve temporal alterations in membrane metabolite and protein signatures during high-fat diet (HF)-mediated development of hepatic insulin resistance. METHODS: We induced hepatosteatosis by feeding C3HeB/FeJ male mice an HF enriched with long-chain polyunsaturated C18:2n6 fatty acids for 7, 14, or 21 days. Longitudinal changes in hepatic insulin sensitivity were assessed via the euglycemic-hyperinsulinemic clamp, in membrane lipids via t-metabolomics- and membrane proteins via quantitative proteomics-analyses, and in hepatocyte morphology via electron microscopy. Data were compared to those of age- and litter-matched controls maintained on a low-fat diet. RESULTS: Excess long-chain polyunsaturated C18:2n6 intake for 7 days did not compromise hepatic insulin sensitivity, however, induced hepatosteatosis and modified major membrane lipid constituent signatures in liver, e.g. increased total unsaturated, long-chain fatty acid-containing acyl-carnitine or membrane-associated diacylglycerol moieties and decreased total short-chain acyl-carnitines, glycerophosphocholines, lysophosphatidylcholines, or sphingolipids. Hepatic insulin sensitivity tended to decrease within 14 days HF-exposure. Overt hepatic insulin resistance developed until day 21 of HF-intervention and was accompanied by morphological mitochondrial abnormalities and indications for oxidative stress in liver. HF-feeding progressively decreased the abundance of protein-components of all mitochondrial respiratory chain complexes, inner and outer mitochondrial membrane substrate transporters independent from the hepatocellular mitochondrial volume in liver. CONCLUSIONS: We assume HF-induced modifications in membrane lipid- and protein-signatures prior to and during changes in hepatic insulin action in liver alter membrane properties - in particular those of mitochondria which are highly abundant in hepatocytes. In turn, a progressive decrease in the abundance of mitochondrial membrane proteins throughout HF-exposure likely impacts on mitochondrial energy metabolism, substrate exchange across mitochondrial membranes, contributes to oxidative stress, mitochondrial damage, and the development of insulin resistance in liver.

7.
J Am Acad Orthop Surg ; 6(1): 24-35, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9692938

RESUMO

Dupuytren's contracture is a fibroproliferative disorder of autosomal dominant inheritance that most commonly affects men over age 60 who are of Scandinavian, Irish, or eastern European descent. Local microvessel ischemia in the hand and specific platelet-derived and fibroblast growth factors act at the cellular level to promote the dense myofibroblast population and altered collagen profiles seen in affected tissue. Surgical treatment depends to some degree on patient preference and a clear understanding of the possible complications and considerable postoperative therapy commitment. Operative management is appropriate when metacarpophalangeal or proximal interphalangeal joint contracture exceeds 30 degrees. A volar zigzag Brunner incision in the digit and palm provides reliable exposure and leads to predictable healing in most cases. The mainstay of postoperative hand therapy is early active-flexion range-of-motion exercises to restore grip strength. A nighttime extension splint is often used for several months postoperatively to maintain the correction achieved in the operating room. Early recurrence of disease is most common in individuals with Dupuytren's diathesis; use of full-thickness skin grafts may be helped for these patients.


Assuntos
Contratura de Dupuytren , Contratura de Dupuytren/etiologia , Contratura de Dupuytren/patologia , Contratura de Dupuytren/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
8.
Hepatogastroenterology ; 27(5): 372-6, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6782001

RESUMO

Among the pathological changes producing dysphagia, cysts are of only minor importance. Intramural pseudodiverticulosis of the esophagus as a consequence of cystic esophagitis with scarring of the submucosa and subsequent stenosis, has been observed more frequently in recent years. Congenital cysts are rarely diagnosed preoperatively. Their removal presents no technical problems. It should be remembered that esophageal cysts might be the reason for dysphagia.


Assuntos
Cisto Esofágico/diagnóstico , Adulto , Idoso , Transtornos de Deglutição/etiologia , Divertículo Esofágico/etiologia , Cisto Esofágico/congênito , Cisto Esofágico/cirurgia , Estenose Esofágica/etiologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Humanos , Radiografia
9.
Chirurg ; 55(4): 275-9, 1984 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-6426894

RESUMO

14 male patients with cancer of the colon were enterally fed for 2 days preoperatively, on the day of the operation and 5 days postoperatively with a high-caloric oligopeptide diet without the additional enteral administration of calories. All the anastomoses (5 rectal and 5 sigmoid colon resections as well as 4 hemicolectomies ) healed without problems; no complications occurred . The nutrition was well tolerated without exception and the jejunal tube tolerated without discomfort. The short-lived function proteins fell during postoperative metabolism. However, the means for total protein, albumin, prealbumin, transferrin and the immunoglobulins (IgM, IgG, IgA und IgD) were still within the lower part of the normal range. Only retinol-binding protein fell to values up to 30% below normal.


Assuntos
Colectomia , Nutrição Enteral , Proteínas Sanguíneas/análise , Neoplasias do Colo/cirurgia , Neoplasias do Colo/terapia , Eletrólitos/sangue , Nutrição Enteral/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Cuidados Pós-Operatórios , Albumina Sérica/análise
10.
Chirurg ; 51(12): 777-9, 1980 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-7471954

RESUMO

Congenital cysts of the esophagus are rare tumors of the mediastinum. They are classified as foregut-cysts. Most of them are found accidentally on routine chest X-ray. They are seldom diagnosed preoperatively. Exstirpation of the cysts presents no major problems. Five patients with congenital esophageal cysts are presented.


Assuntos
Cisto Esofágico/congênito , Adulto , Idoso , Cisto Esofágico/diagnóstico por imagem , Cisto Esofágico/embriologia , Cisto Esofágico/cirurgia , Humanos , Pessoa de Meia-Idade , Radiografia
11.
Chirurg ; 51(9): 592-3, 1980 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-7460685

RESUMO

Knowledge of normal and pathological anatomy and the radiological picture of the ileocecal valve is very important to avoid false interpretation of polyp-like findings in the cecum. Radiologically, ileal prolapse can pose as a cecal polyp. The radiological diagnosis, large 'cecal polyp' was not confirmed intraoperatively in the case presented.


Assuntos
Doenças do Íleo/cirurgia , Valva Ileocecal/cirurgia , Mucosa Intestinal/cirurgia , Neoplasias do Ceco/diagnóstico por imagem , Neoplasias do Ceco/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Doenças do Íleo/diagnóstico por imagem , Pólipos Intestinais/diagnóstico por imagem , Pólipos Intestinais/cirurgia , Pessoa de Meia-Idade , Prolapso/cirurgia , Radiografia
12.
Chirurg ; 51(3): 155-7, 1980 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-6105047

RESUMO

Somatostatin (GIF) was administered to a patient with persisting intestinal fistulas. Somatostatin reduced the tryptical activity of the secretions which subsequently subsided.


Assuntos
Doenças do Íleo/tratamento farmacológico , Fístula Intestinal/tratamento farmacológico , Somatostatina/uso terapêutico , Adulto , Colite Ulcerativa/cirurgia , Feminino , Humanos , Fístula Intestinal/etiologia , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Tripsina/metabolismo
13.
Chirurg ; 52(10): 643-7, 1981 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-7297203

RESUMO

About 1-2% of all tumors are found in the mediastinum. Any space-occupying swelling of the mediastinum has to be exstirpated. Even if a carcinoma cannot be completely removed, the tumor mass should be reduced as much as possible. The operation must not be delayed by any diagnostic uncertainties.


Assuntos
Neoplasias do Mediastino/cirurgia , Diagnóstico Diferencial , Humanos , Neoplasias do Mediastino/diagnóstico por imagem , Avaliação de Processos e Resultados em Cuidados de Saúde , Radiografia
14.
Chirurg ; 53(2): 112-6, 1982 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-7075339

RESUMO

Specificity of cellular immunity was verified by the cell migration inhibition test in 36 patients with colorectal cancer and 15 with colorectal adenomas. The electrophoretic mobility test is considered as an indirect method for demonstrating cellular immunity against malignant tumors. Soluble potassium chloride tumor extracts from various human carcinomas were used as antigens. In 31 of 36 tumor patients, a specific lymphocytic sensitization against antigens of colorectal carcinomas could be shown. Lymphocytic reactions to antigens from histologically different tumors (cross-reactions) were weaker or negative. This reaction, verified for carcinomas, was also noted in cases with precancerous lesions. Measurements in 54 healthy control persons with the same antigenic substances showed negative results in 48 cases. Acute inflammatory lesions of the colon reduce the reliability of the test.


Assuntos
Neoplasias do Colo/imunologia , Neoplasias Retais/imunologia , Adenocarcinoma/imunologia , Adenoma/imunologia , Antígenos de Neoplasias , Inibição de Migração Celular , Neoplasias do Colo/patologia , Reações Cruzadas , Humanos , Imunidade Celular , Linfócitos/imunologia , Especificidade de Órgãos , Lesões Pré-Cancerosas/imunologia , Neoplasias Retais/patologia
15.
Aktuelle Traumatol ; 20(2): 83-6, 1990 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-1971483

RESUMO

Primary open reduction and fixation with Kirschner wires and/or fascia lata or PDS is recommended in the treatment of acute traumatic luxations of the sternoclavicular joint. If not bent or secured against migration, K-wires may be the reason for lethal postoperative complications. We report on 7 own patients with luxation of the sternoclavicular joint and discuss the problems in diagnosis, operative and postoperative treatment of this rare lesion.


Assuntos
Luxações Articulares/diagnóstico por imagem , Articulação Esternoclavicular/lesões , Adulto , Feminino , Humanos , Luxações Articulares/cirurgia , Masculino , Métodos , Cuidados Pós-Operatórios , Radiografia , Articulação Esternoclavicular/diagnóstico por imagem , Articulação Esternoclavicular/cirurgia
19.
Histochem Cell Biol ; 127(2): 139-48, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16957816

RESUMO

Nuclear myosin I (NMI) is a single-headed member of myosin superfamily localized in the cell nucleus which participates along with nuclear actin in transcription and chromatin remodeling. We demonstrate that NMI is present in cell nuclei of all mouse tissues examined except for cells in terminal stages of spermiogenesis. Quantitative PCR and western blots demonstrate that the expression of NMI in tissues varies with the highest levels in the lungs. The expression of NMI is lower in serum-starved cells and it increases after serum stimulation. The lifespan of NMI is longer than 16 h as determined by cycloheximide translation block. A homologous protein is expressed in human, chicken, Xenopus, and zebrafish as shown by RACE analysis. The analysis of genomic sequences indicates that almost identical homologous NMI genes are expressed in mammals, and similar NMI genes in vertebrates.


Assuntos
Núcleo Celular/metabolismo , Miosina Tipo I/metabolismo , Vertebrados/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Sequência Conservada , Feminino , Expressão Gênica , Humanos , Masculino , Camundongos , Miosina Tipo I/química , Miosina Tipo I/genética , Miosina Tipo I/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Filogenia , Homologia de Sequência do Ácido Nucleico , Soro/química , Transcrição Gênica , Vertebrados/genética
20.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 1110-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282383

RESUMO

We recently proposed an adaptive filtering method for removing ocular artifacts from EEG recordings. In this study, the accuracy of this method is evaluated quantitatively using simulated data and compared with the accuracy of the time domain regression method. The results show that when transfer of ocular signal to EEG channel is frequency dependent, or when there is a time delay, the adaptive filtering method is more accurate in recovering the true EEG signals.

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