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1.
Prev Med ; 182: 107925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38437923

RESUMO

OBJECTIVE: Many school-based intervention studies are conducted to increase students' physical activity (PA). Recruitment and retention problems potentially impact the robustness of RCT findings. We conducted a meta-analysis to summarize recruitment and retention rates in long-term secondary school-based PA intervention studies and examined associated participant and intervention characteristics. METHODS: Web of Science, Pubmed, Medline, and PsychInfo were searched until March 20th 2023. We included studies on secondary school-based PA interventions ≥12 weeks, aimed at typically developing adolescents. We abstracted number of schools and students invited, randomized, and participating at follow-up to calculate pooled recruitment and retention rates; participant and intervention characteristics were abstracted to execute subgroup or meta-regression analyses. RESULTS: Recruitment rates were 51% for invited schools and 80% for invited students, the retention for schools was almost 100% and for students 91%. Interventions with fixed and flexible components, executed in Asia and South America, and from later publication years had higher student recruitment rates. Students' retention rates were lower for interventions which had flexible components, were theory/model-based, used an accelerometer, had a longer intervention duration, and included more females. CONCLUSION: Recruitment and retention rates in school-based PA interventions are high. Some participant and intervention characteristics influence these rates: flexibility of the intervention, theory/model-based intervention, accelerometer use, intervention duration, continent, and number of females. Researchers should consider these characteristics in intervention development to achieve optimal balance between intervention effectiveness, recruitment, and retention.

2.
Nephrologe ; 15(3): 191-204, 2020.
Artigo em Alemão | MEDLINE | ID: mdl-32351619

RESUMO

Systemic treatment with immune checkpoint inhibitors (ICI) has revolutionized the treatment of hematological and oncological diseases in recent years. The mechanism of action hinges on enhancing the natural ability of the immune system to eliminate malignant cells. The most important substances in this arena include inhibitors of PD­1, PD-L1 and CTLA­4. As a consequence, the spectrum of treatment-associated adverse reactions is shifting away from classical cytotoxic effects (e.g. pancytopenia and polyneuropathy) towards novel entities of immune-mediated complex diseases. These so-called immune-related adverse events (irAEs) can involve any organ system and mimic known classical autoimmune conditions. Timely recognition of irAEs is the key for rapid initiation of a suitable treatment and is especially challenging in the clinical routine as it requires an intensive interdisciplinary management. Nephrologists are particularly confronted with this kind of problem due to the highly interdisciplinary nature of their work. This article summarizes the broad spectrum of currently known renal and more frequently occuring non-renal forms of irAEs and aims to prime the reader on diagnostic and therapeutic options.

4.
Acta Neurol Scand ; 135(4): 449-453, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27444636

RESUMO

OBJECTIVES: There are clinical situations where it might be appropriate to switch patients from immediate-release oxcarbazepine (OXC) to eslicarbazepine acetate (ESL). We investigated the effects of transitioning patients overnight from OXC to ESL. MATERIALS AND METHODS: A retrospective, single-center study was conducted in which patients with drug-resistant focal epilepsy on a stable dose of immediate-release OXC for at least 4 weeks were switched overnight to ESL. Patients were switched because they experienced persistent seizures with OXC but were unable to tolerate increased OXC dosing due to adverse events. Tolerability was assessed using the Adverse Events Profile (AEP), quality of life was assessed using the Quality of Life in Epilepsy Inventory 10 (QOLIE-10), and alertness was assessed as reaction time using a subtest of the Test Battery for Attention Performance version 2.3. Assessments were performed immediately prior to and 5 days after switching from OXC to ESL (days 0 and 5, respectively). RESULTS: The analysis included 21 patients (12 women, 9 men; mean age 36 years). After switching from OXC to ESL, there were significant improvements in mean scores for AEP (P<.001), QOLIE-10 (P=.001), and alertness (P<.05). Adverse Events Profile total scores improved for 21/21 (100.0%) patients, QOLIE-10 total scores improved for 17/21 (81.0%) patients, and alertness scores improved for 16/21 (76.2%) patients. CONCLUSIONS: In this short-term, single-center study, an overnight switch from twice-daily OXC to once-daily ESL in patients with drug-resistant focal epilepsies resulted in improvements in side effects, quality of life, and alertness.


Assuntos
Anticonvulsivantes/uso terapêutico , Carbamazepina/análogos & derivados , Dibenzazepinas/uso terapêutico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Substituição de Medicamentos/efeitos adversos , Adulto , Idoso , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Carbamazepina/administração & dosagem , Carbamazepina/efeitos adversos , Carbamazepina/uso terapêutico , Dibenzazepinas/administração & dosagem , Dibenzazepinas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxcarbazepina
5.
J Hematol Oncol ; 9: 18, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26944254

RESUMO

BACKGROUND: Patients with Ph-negative myeloproliferative neoplasms (MPN), such as polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are at increased risk for thrombosis/thromboembolism and major bleeding. Due to the morbidity and mortality of these events, antiplatelet and/or anticoagulant agents are commonly employed as primary and/or secondary prophylaxis. On the other hand, disease-related bleeding complications (i.e., from esophageal varices) are common in patients with MPN. This analysis was performed to define the frequency of such events, identify risk factors, and assess antiplatelet/anticoagulant therapy in a cohort of patients with MPN. METHODS: The MPN registry of the Study Alliance Leukemia is a non-interventional prospective study including adult patients with an MPN according to WHO criteria (2008). For statistical analysis, descriptive methods and tests for significant differences as well as contingency tables were used to identify the odds of potential risk factors for vascular events. RESULTS: MPN subgroups significantly differed in sex distribution, age at diagnosis, blood counts, LDH levels, JAK2V617F positivity, and spleen size (length). While most thromboembolic events occurred around the time of MPN diagnosis, one third of these events occurred after that date. Splanchnic vein thrombosis was most frequent in post-PV-MF and MPN-U patients. The chance of developing a thromboembolic event was significantly elevated if patients suffered from post-PV-MF (OR 3.43; 95% CI = 1.39-8.48) and splenomegaly (OR 1.76; 95% CI = 1.15-2.71). Significant odds for major bleeding were previous thromboembolic events (OR = 2.71; 95% CI = 1.36-5.40), splenomegaly (OR = 2.22; 95% CI 1.01-4.89), and the administration of heparin (OR = 5.64; 95% CI = 1.84-17.34). Major bleeding episodes were significantly less frequent in ET patients compared to other MPN subgroups. CONCLUSIONS: Together, this report on an unselected "real-world" cohort of German MPN patients reveals important data on the prevalence, diagnosis, and treatment of thromboembolic and major bleeding complications of MPN.


Assuntos
Coagulação Sanguínea/fisiologia , Hemorragia/fisiopatologia , Transtornos Mieloproliferativos/fisiopatologia , Sistema de Registros/estatística & dados numéricos , Trombose/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Alemanha/epidemiologia , Hemorragia/diagnóstico , Hemorragia/prevenção & controle , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/epidemiologia , Prevalência , Estudos Prospectivos , Esplenomegalia/diagnóstico , Esplenomegalia/fisiopatologia , Trombose/diagnóstico , Trombose/prevenção & controle
6.
Br J Cancer ; 110(2): 510-9, 2014 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-24327015

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive tumour originating in the thoracic mesothelium. Prognosis remains poor with 9- to 12-month median survival, and new targets for treatments are desperately needed. METHODS: Utilising an RNA interference (RNAi)-based screen of 40 genes overexpressed in tumours, including genes involved in the control of cell cycle, DNA replication and repair, we investigated potential therapeutic targets for MPM. Following in vitro characterisation of the effects of target silencing on MPM cells, candidates were assessed in tumour samples from 154 patients. RESULTS: Gene knockdown in MPM cell lines identified growth inhibition following knockdown of NDC80, CDK1 and PLK1. Target knockdown induced cell-cycle arrest and increased apoptosis. Using small-molecule inhibitors specific for these three proteins also led to growth inhibition of MPM cell lines, and Roscovitine (inhibitor of CDK1) sensitised cells to cisplatin. Protein expression was also measured in tumour samples, with markedly variable levels of CDK1 and PLK1 noted. PLK1 expression in over 10% of cells correlated significantly with a poor prognosis. CONCLUSION: These results suggest that RNAi-based screening has utility in identifying new targets for MPM, and that inhibition of NDC80, CDK1 and PLK1 may hold promise for treatment of this disease.


Assuntos
Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Mesotelioma/tratamento farmacológico , Mesotelioma/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Sanguíneas/genética , Proteína Quinase CDC2/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Proteínas do Citoesqueleto , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/genética , Humanos , Neoplasias Pulmonares/genética , Mesotelioma/genética , Mesotelioma Maligno , Terapia de Alvo Molecular , Proteínas Nucleares/genética , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/genética , Neoplasias Pleurais/metabolismo , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Purinas/farmacologia , Estudos Retrospectivos , Roscovitina , Quinase 1 Polo-Like
7.
Ann Oncol ; 24(12): 3128-35, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24148817

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is recalcitrant to treatment and new approaches to therapy are needed. Reduced expression of miR-15/16 in a range of cancer types has suggested a tumour suppressor function for these microRNAs, and re-expression has been shown to inhibit tumour cell proliferation. The miR-15/16 status in MPM is largely unknown. MATERIALS AND METHODS: MicroRNA expression was analysed by TaqMan-based RT-qPCR in MPM tumour specimens and cell lines. MicroRNA expression was restored in vitro using microRNA mimics, and effects on proliferation, drug sensitivity and target gene expression were assessed. Xenograft-bearing mice were treated with miR-16 mimic packaged in minicells targeted with epidermal growth factor receptor (EGFR)-specific antibodies. RESULTS: Expression of the miR-15 family was consistently downregulated in MPM tumour specimens and cell lines. A decrease of 4- to 22-fold was found when tumour specimens were compared with normal pleura. When MPM cell lines were compared with the normal mesothelial cell line MeT-5A, the downregulation of miR-15/16 was 2- to 10-fold. Using synthetic mimics to restore miR-15/16 expression led to growth inhibition in MPM cell lines but not in MeT-5A cells. Growth inhibition caused by miR-16 correlated with downregulation of target genes including Bcl-2 and CCND1, and miR-16 re-expression sensitised MPM cells to pemetrexed and gemcitabine. In xenograft-bearing nude mice, intravenous administration of miR-16 mimics packaged in minicells led to consistent and dose-dependent inhibition of MPM tumour growth. CONCLUSIONS: The miR-15/16 family is downregulated and has tumour suppressor function in MPM. Restoring miR-16 expression represents a novel therapeutic approach for MPM.


Assuntos
Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , MicroRNAs/genética , Neoplasias Pleurais/metabolismo , Animais , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Glutamatos/farmacologia , Guanina/análogos & derivados , Guanina/farmacologia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Mesotelioma/patologia , Mesotelioma/terapia , Mesotelioma Maligno , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Transplante de Neoplasias , Pemetrexede , Neoplasias Pleurais/patologia , Neoplasias Pleurais/terapia , Interferência de RNA , Transfecção , Carga Tumoral , Gencitabina
8.
Anaesthesist ; 62(5): 396-404, 2013 May.
Artigo em Alemão | MEDLINE | ID: mdl-23670582

RESUMO

There are currently many assistant professions in the German healthcare system which have either a more nursing or a more medical character. All these assistant professions have in common that as yet they do not require uniform training criteria but members of these professions undertake some aspects of medical activities. At the center lies the difficulty of more political than legal discussion on whether members of these assistant professions and also nursing personnel are allowed to or should undertake medical activities. This article illuminates the legal status quo.


Assuntos
Recursos Humanos em Hospital/legislação & jurisprudência , Alemanha , Ocupações em Saúde/legislação & jurisprudência , Humanos , Responsabilidade Legal , Designação de Pessoal , Recursos Humanos em Hospital/normas , Assistentes Médicos
9.
Methods Inf Med ; 51(5): 398-405, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23038636

RESUMO

BACKGROUND: Osteoporosis can cause severe fractures of bone structures. One important indicator for pathology is a lowered bone mineral density (BMD) - conventionally assessed by dual-energy X-ray absorptiometry (DXA). Dual-energy CT (DECT) - being an alternative that is increasingly used in the clinics - allows the computation of the spatial BMD distribution. OBJECTIVES: Using DECT, the trabecular bone of vertebrae is examined. Several analysis methods for revealing the bone density distribution as well as appropriate visualization methods for detecting regions of lowered BMD are needed for computer-assisted diagnosis (CAD) of osteoporosis. The hypothesis that DECT is better suited than DXA for the computation of local BMD is investigated. METHODS: Building on a model of the interaction of X-rays with bone tissue, novel methods for assessing the spatial structure of the trabecular bone are presented. CAD of DECT image data is facilitated by segmenting the regions of interest interactively and with an Active Shape Model, respectively. The barycentric space of fractional volumes is introduced as a novel means for analyzing bone constitution. For 29 cadaver specimens, DECT as well as DXA has been examined. BMD values derived from both modalities are compared to local force measurements. In addition, clinical data from two patients who underwent DECT scanning for a different reason is analyzed retrospectively. RESULTS: A novel automated delineation method for vertebrae has been successfully applied to DECT data sets. It is shown that localized BMD measurements based on DECT show a stronger linear correlation (R² = 0.8242, linear regression) to local force measurements than density values derived from DXA (R² = 0.4815). CONCLUSIONS: DECT based BMD assessment is a method to extend the usage of increasingly acquired DECT image data. The developed DECT based analysis methods in conjunction with the visualization provide more detailed information for both, the radiologist and the orthopedist, compared to standard DXA based analysis.


Assuntos
Absorciometria de Fóton , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Densidade Óssea , Cadáver , Humanos , Imageamento Tridimensional , Modelos Estatísticos , Osteoporose/diagnóstico por imagem
10.
Clin Lab ; 56(11-12): 535-42, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21141437

RESUMO

BACKGROUND: Proteolysis of Insulin-like Growth Factor Binding Protein (IGFBP)--3 is a well known mechanism regulating IGF-I bioavailability and IGF-independent actions of IGFBP-3 fragments. Measurement of functional IGFBP-3 can be of use in diagnostics of growth failure or renal impairment. We herein characterize the properties of a commercially available immunoassay for the measurement of functional (IGF-I binding) IGFBP-3. METHOD: Fragmentation of IGFBP-3 is analyzed by gel filtration, SDS-PAGE, and western ligand and immunoblotting and compared with subsequent measurement of total and functional IGFBP-3 by ELISA/IFA. Furthermore, assay characteristics such as reproducibility, linearity, and sensitivity are surveyed. RESULTS: Functional IGFBP-3 was reproducibly measured (6.8/5.6% Inter-/Intra assay variance). A broad range of linearity (1:50-1:300) and a high sensitivity (0.18 microg/L) allowed reliable measurement of IGF-binding IGFBP-3. Analysis of IGFBP-3 fragments reveals that the assay described only detects intact IGFBP-3. Analysis of 189 serum samples from healthy blood donors showed that on average 84% and 69% of total IGFBP-3 was functional in men and women, respectively (p < 0.01). CONCLUSIONS: Functional IGFBP-3 can be measured reliably by the assay system used. Thus, this assay system is suited for the investigation of the diagnostic value of functional IGFBP-3 in human body fluids.


Assuntos
Imunoensaio/métodos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Adulto , Western Blotting , Calibragem , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Int J Comput Assist Radiol Surg ; 5(6): 655-66, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20512631

RESUMO

PURPOSE: Surgical planning requires 3D volume visualizations based on transfer functions (TF) that assign optical properties to volumetric image data. Two-dimensional TFs and 2D histograms may be employed to improve overall performance. METHODS: Anatomical structures were used for 2D TF definition in an algorithm that computes a new structure-size image from the original data set. The original image and structure-size data sets were used to generate a structure-size enhanced (SSE) histogram. Alternatively, the gradient magnitude could be used as second property for 2D TF definition. Both types of 2D TFs were generated and compared using subjective evaluation of anatomic feature conspicuity. RESULTS: Experiments with several medical image data sets provided SSE histograms that were judged subjectively to be more intuitive and better discriminated different anatomical structures than gradient magnitude-based 2D histograms. CONCLUSIONS: In clinical applications, where the size of anatomical structures is more meaningful than gradient magnitude, the 2D TF can be effective for highlighting anatomical structures in 3D visualizations.


Assuntos
Algoritmos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Humanos
12.
Eur J Med Res ; 14(3): 123-9, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19380283

RESUMO

OBJECTIVE: Tissue hypoxia after blood loss, replantation and flap reperfusion remains a challenging task in surgery. Normovolemic hemodilution improves hemorheologic properties without increasing oxygen carrying capacity. Red blood cell transfusion is the current standard of treatment with its attendant risks. The aim of this study was to investigate the potential of the chemically modified hemoglobin, MP4, to reduce skin flap necrosis and its effect on selected blood markers and kidneys. MATERIALS AND METHODS: Tissue ischemia was induced in the ear of hairless mice (n=26). Hemodilution was performed by replacing one third of blood volume with the similar amount of MP4, dextran, or blood. The extent of non-perfused tissue was assessed by intravital fluorescent microscopy. RESULTS: Of all groups, MP4 showed the smallest area of no perfusion (in percentage of the ear +/- SEM: 16.3% +/- 2.4), the control group the largest (22.4% +/- 3.5). Leukocytes showed a significant increase in the MP4 and dextran group (from 8.7 to 13.6 respectively 15.4*109/l). On histology no changes of the kidneys could be observed. CONCLUSION: MP4 causes an increase of leukocytes, improves the oxygen supply of the tissue and shows no evidence of renal impairment.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Hemoglobinas/farmacologia , Maleimidas/farmacologia , Necrose/tratamento farmacológico , Polietilenoglicóis/farmacologia , Pele/efeitos dos fármacos , Animais , Dextranos/administração & dosagem , Dextranos/farmacologia , Modelos Animais de Doenças , Orelha/irrigação sanguínea , Orelha/patologia , Hemodiluição , Hemoglobinas/administração & dosagem , Injeções , Leucócitos/efeitos dos fármacos , Maleimidas/administração & dosagem , Camundongos , Camundongos Pelados , Polietilenoglicóis/administração & dosagem , Fluxo Sanguíneo Regional/efeitos dos fármacos , Pele/patologia , Retalhos Cirúrgicos/patologia
13.
Biol Bull ; 214(3): 284-302, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18574105

RESUMO

We describe a collection of expressed sequence tags (ESTs) for Saccoglossus kowalevskii, a direct-developing hemichordate valuable for evolutionary comparisons with chordates. The 202,175 ESTs represent 163,633 arrayed clones carrying cDNAs prepared from embryonic libraries, and they assemble into 13,677 continuous sequences (contigs), leaving 10,896 singletons (excluding mitochondrial sequences). Of the contigs, 53% had significant matches when BLAST was used to query the NCBI databases (< or = 10(-10)), as did 51% of the singletons. Contigs most frequently matched sequences from amphioxus (29%), chordates (67%), and deuterostomes (87%). From the clone array, we isolated 400 full-length sequences for transcription factors and signaling proteins of use for evolutionary and developmental studies. The set includes sequences for fox, pax, tbx, hox, and other homeobox-containing factors, and for ligands and receptors of the TGFbeta, Wnt, Hh, Delta/Notch, and RTK pathways. At least 80% of key sequences have been obtained, when judged against gene lists of model organisms. The median length of these cDNAs is 2.3 kb, including 1.05 kb of 3' untranslated region (UTR). Only 30% are entirely matched by single contigs assembled from ESTs. We conclude that an EST collection based on 150,000 clones is a rich source of sequences for molecular developmental work, and that the EST approach is an efficient way to initiate comparative studies of a new organism.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Fatores de Transcrição/genética , Regiões 3' não Traduzidas , Animais , Etiquetas de Sequências Expressas , Biblioteca Gênica , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
14.
J Cell Mol Med ; 12(2): 479-95, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18194455

RESUMO

Changes in protein subdomains through alternative splicing often modify protein-protein interactions, altering biological processes. A relevant example is that of the stress-induced up-regulation of the acetylcholinesterase (AChE-R) splice variant, a common response in various tissues. In germ cells of male transgenic TgR mice, AChE-R excess associates with reduced sperm differentiation and sperm counts. To explore the mechanism(s) by which AChE-R up-regulation affects spermatogenesis, we identified AChE-R's protein partners through a yeast two-hybrid screen. In meiotic spermatocytes from TgR mice, we detected AChE-R interaction with the scaffold protein RACK1 and elevated apoptosis. This correlated with reduced scavenging by RACK1 of the pro-apoptotic TAp73, an outcome compatible with the increased apoptosis. In contrast, at later stages in sperm development, AChE-R's interaction with the glycolytic enzyme enolase-alpha elevates enolase activity. In transfected cells, enforced AChE-R excess increased glucose uptake and adenosine tri-phosphate (ATP) levels. Correspondingly, TgR sperm cells display elevated ATP levels, mitochondrial hyperactivity and increased motility. In human donors' sperm, we found direct association of sperm motility with AChE-R expression. Interchanging interactions with RACK1 and enolase-alpha may hence enable AChE-R to affect both sperm differentiation and function by participating in independent cellular pathways.


Assuntos
Acetilcolinesterase/metabolismo , Apoptose , Motilidade dos Espermatozoides , Espermatozoides/enzimologia , Espermatozoides/fisiologia , Acetilcolinesterase/genética , Processamento Alternativo , Animais , Apoptose/genética , Biópsia , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Motilidade dos Espermatozoides/genética , Espermatozoides/citologia , Testículo/citologia , Testículo/enzimologia , Testículo/metabolismo , Testículo/fisiologia , Testículo/cirurgia
16.
Unfallchirurg ; 110(10): 859-66, 2007 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-17805505

RESUMO

BACKGROUND: Noninvasive diagnosis continues to present a challenge in chronic bone infections. Positive intraoperative microbiological and/or histological results are regarded as the gold standard for confirmation of the diagnosis. The aim of the present study was to evaluate the value of F-18 FDG-PET in the diagnosis of chronic osteitis in the patients of a department devoted specifically to septic orthopaedic surgery. In particular, the study was intended to answer the question of whether the results of FDG-PET correlate with those found in intraoperatively removed biopsy specimens (microbiology, histology) and what value this method of investigation has relative to computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: An F-18 FDG-PET examination was performed preoperatively in each of 50 patients with a suspected diagnosis of "chronic osteitis of bone/s in a limb". All these patients had a history of an open fracture and/or a previous operation on the affected limb. The FDG-PET results were analysed blind. All patients enrolled in the study were subsequently operated on. After surgery, the results of histological and microbiological examination of the biopsy specimens taken intraoperatively were compared with the results of the FDG-PET and of CT (n=22) and MRI (n=18). Finally, the sensitivity, specificity and accuracy of each method were determined. RESULTS: Postoperatively the biopsy specimens from 37 patients yielded positive results in the microbiological and/or histological tests. According to this gold standard, then, osteitis was not present in 13 patients. In the preoperative FDG-PET report 34 of the patients whose microbiological and/or histological results were positive were correctly diagnosed as infection positive. In addition, 4 false-positive results were observed. False-negative results were recorded in 3 patients and true-negative results, in 9. The sensitivity and specificity were 92% and 69%, respectively, for the entire group of patients. The accuracy was 86%. The sensitivity, specificity and accuracy were 47%, 60% and 50%, respectively, for CT and 82%, 43% and 67%, respectively, for MRI. CONCLUSION: F-18 FDG-PET is a promising diagnostic imaging method with high sensitivity and accuracy in the investigation of chronic osteitis. If the result of FDG-PET is negative chronic osteitis can be virtually excluded. The results presented suggest that it is superior to CT and MRI in sensitivity and accuracy. A definitive diagnosis of chronic osteitis will continue to require an invasive method in the future, in the form of removal of biopsy specimens for microbiological and histological tests.


Assuntos
Infecções Bacterianas/diagnóstico por imagem , Glicemia/metabolismo , Osteíte/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias/diagnóstico por imagem , Infecção da Ferida Cirúrgica/diagnóstico por imagem , Adulto , Idoso , Traumatismos do Braço/diagnóstico por imagem , Traumatismos do Braço/cirurgia , Infecções Bacterianas/patologia , Infecções Bacterianas/cirurgia , Técnicas Bacteriológicas , Biópsia , Osso e Ossos/patologia , Doença Crônica , Feminino , Fluordesoxiglucose F18 , Fraturas Expostas/patologia , Fraturas Expostas/cirurgia , Humanos , Traumatismos da Perna/diagnóstico por imagem , Traumatismos da Perna/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteíte/patologia , Osteíte/cirurgia , Complicações Pós-Operatórias/cirurgia , Valor Preditivo dos Testes , Reoperação , Sensibilidade e Especificidade , Infecção da Ferida Cirúrgica/patologia , Infecção da Ferida Cirúrgica/cirurgia , Tomografia Computadorizada por Raios X
17.
Nature ; 446(7138): 921-5, 2007 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-17443186

RESUMO

Eukaryotic cells rely on a surveillance mechanism known as the spindle checkpoint to ensure accurate chromosome segregation. The spindle checkpoint prevents sister chromatids from separating until all kinetochores achieve bipolar attachments to the mitotic spindle. Checkpoint proteins tightly inhibit the anaphase-promoting complex (APC), a ubiquitin ligase required for chromosome segregation and progression to anaphase. Unattached kinetochores promote the binding of checkpoint proteins Mad2 and BubR1 to the APC-activator Cdc20, rendering it unable to activate APC. Once all kinetochores are properly attached, however, cells inactivate the checkpoint within minutes, allowing for the rapid and synchronous segregation of chromosomes. How cells switch from strong APC inhibition before kinetochore attachment to rapid APC activation once attachment is complete remains a mystery. Here we show that checkpoint inactivation is an energy-consuming process involving APC-dependent multi-ubiquitination. Multi-ubiquitination by APC leads to the dissociation of Mad2 and BubR1 from Cdc20, a process that is reversed by a Cdc20-directed de-ubiquitinating enzyme. The mutual regulation between checkpoint proteins and APC leaves the cell poised for rapid checkpoint inactivation and ensures that chromosome segregation promptly follows the completion of kinetochore attachment. In addition, our results suggest a mechanistic basis for how cancer cells can have a compromised spindle checkpoint without corresponding mutations in checkpoint genes.


Assuntos
Fuso Acromático/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Ubiquitina/metabolismo , Ciclossomo-Complexo Promotor de Anáfase , Segregação de Cromossomos , Células HeLa , Humanos , Cinetocoros/efeitos dos fármacos , Cinetocoros/metabolismo , Nocodazol/farmacologia , Fuso Acromático/efeitos dos fármacos , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo
19.
Chirurg ; 77(3): 267-72, 2006 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-16496099

RESUMO

BACKGROUND: INSECT is an internationally registered, three-armed, multicentre, intraoperatively randomised model trial of the Study Centre of the German Surgical Society. The interventions being compared are running suture technique with slowly absorbable monofilament suture material (PDS vs MonoPlus) and interrupted technique with a braided, rapidly absorbable suture material (Vicryl). The primary endpoint is the rate of incisional hernias 1 year postoperatively. MATERIAL AND METHODS: A total of 25 surgeons from 24 different institutions at all levels of care evaluated the theoretical and practical sessions of the surgical investigator meeting using 25 criteria, including course organisation, content, and speaker evaluation, and a categorical grading system from 1 (very good) to 6 (insufficient). RESULTS: Distribution of the 625 grades was: very good (1) n=367, good (2) n=207, satisfactory (3) n=39, adequate (4) n=2, and "No statement" n=10. The average score for the investigator meeting was 1.5. CONCLUSION: The participants felt they were successfully prepared theoretically and practically for trial interventions and conduct by attending the meeting. Clear explanation of the measures for treatment equivalence before and during trials is mandatory in randomised controlled surgical trials.


Assuntos
Parede Abdominal/cirurgia , Protocolos Clínicos/normas , Hérnia Abdominal/etiologia , Polidioxanona/normas , Poliglactina 910/normas , Complicações Pós-Operatórias/etiologia , Pesquisadores/educação , Desenvolvimento de Pessoal/normas , Deiscência da Ferida Operatória/etiologia , Técnicas de Sutura/normas , Suturas/normas , Animais , Humanos , Modelos Animais , Avaliação de Programas e Projetos de Saúde , Controle de Qualidade , Centro Cirúrgico Hospitalar , Suínos
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