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1.
Free Radic Biol Med ; 223: 384-397, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39097206

RESUMO

AIM: High-resolution respirometry in human permeabilized muscle fibers is extensively used for analysis of mitochondrial adaptions to nutrition and exercise interventions, and is linked to athletic performance. However, the lack of standardization of experimental conditions limits quantitative inter- and intra-laboratory comparisons. METHODS: In our study, an international team of investigators measured mitochondrial respiration of permeabilized muscle fibers obtained from three biopsies (vastus lateralis) from the same healthy volunteer to avoid inter-individual variability. High-resolution respirometry assays were performed together at the same laboratory to assess whether the heterogenity in published results are due to the effects of respiration media (MiR05 versus Z) with or without the myosin inhibitor blebbistatin at low- and high-oxygen regimes. RESULTS: Our findings reveal significant differences between respiration media for OXPHOS and ETcapacities supported by NADH&succinate-linked substrates at different oxygen concentrations. Respiratory capacities were approximately 1.5-fold higher in MiR05 at high-oxygen regimes compared to medium Z near air saturation. The presence or absence of blebbistatin in human permeabilized muscle fiber preparations was without effect on oxygen flux. CONCLUSION: Our study constitutes a basis to harmonize and establish optimum experimental conditions for respirometric studies of permeabilized human skeletal muscle fibers to improve reproducibility.


Assuntos
Respiração Celular , Mitocôndrias Musculares , Fibras Musculares Esqueléticas , Consumo de Oxigênio , Humanos , Fibras Musculares Esqueléticas/metabolismo , Mitocôndrias Musculares/metabolismo , Fosforilação Oxidativa , Masculino , Oxigênio/metabolismo , Adulto , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Voluntários Saudáveis
2.
JGH Open ; 7(8): 553-558, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37649863

RESUMO

Background and Aim: The DanEoE is a previously described population- and register-based cohort of 236 adult patients with eosinophilic esophagitis (EoE) in a well-defined Danish region with a population of 580 000 and free medical treatment. The aim of the study was to compare the phenotype and treatment response between EoE patients with complications to patients without complications at diagnosis. Methods: A retrospective cross-sectional study of the DanEoE cohort's 236 adult EoE patients diagnosed between 2007 and 2017 in the North Denmark Region. Patients were divided into a group who had had complications (dilated or food bolus obstruction [FBO]) before or at the diagnosis, and a group without. Results: At the diagnostic endoscopy, 61% had never had a complication, and 39% had either had FBO (n = 77) or been dilated (n = 15). The complicated group had the same mean age at symptom debut (37 [SD = 16] vs 37 [SD = 17] years, P = 1.0), but were diagnosed significantly later with a resulting longer diagnostic delay (13 [SD = 13] vs 7.9 [SD = 11] years, P = 0.01). Almost half of all patients were never treated to symptomatic remission (uncomplicated 40%, complicated 49%). The histological remission was not secured in the majority (uncomplicated 68%, complicated 70%). Despite this, <15% of patients with previous FBO experienced this after the diagnosis. Conclusion: In the population-based DanEoE cohort, results indicated that the complicated EoE phenotype was a patient with a 5-year longer diagnostic delay. In the current study, the complication status did not predict the treatment response.

3.
Pancreatology ; 23(5): 512-521, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37230892

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma remains one of the major causes of cancer-related mortality globally. Unfortunately, current prognostic biomarkers are limited, and no predictive biomarkers exist. This study examined promoter hypermethylation of secreted frizzled-related protein 1 (phSFRP1) in cfDNA as a prognostic biomarker and predictor of treatment effect in patients with metastatic FOLFIRINOX-treated PDAC and locally advanced PDAC. METHODS: We performed methylation-specific PCR of the SFRP1 genes' promoter region, based on bisulfite treatment. Survival was assessed as time-to-event data using the pseudo-observation method and analyzed with Kaplan-Meier curves and generalized linear regressions. RESULTS: The study included 52 patients with FOLFIRINOX-treated metastatic PDAC. Patients with unmethylated (um) SFRP1 (n = 29) had a longer median overall survival (15.7 months) than those with phSFRP1 (6.8 months). In crude regression, phSFRP1 was associated with an increased risk of death of 36.9% (95% CI 12.0%-61.7%) and 19.8% (95% CI 1.9-37.6) at 12 and 24-months, respectively. In supplementary regression analysis, interaction terms between SFRP1 methylation status and treatment were significant, indicating reduced benefit of chemotherapy. Forty-four patients with locally advanced PDAC were included. phSFRP1 was associated with an increased risk of death at 24-months CONCLUSIONS: This indicates that phSFRP1 is a clinically useful prognostic biomarker in metastatic PDAC and possibly in locally advanced PDAC. Together with existing literature, results could indicate the value of cfDNA-measured phSFRP1 as a predictive biomarker of standard palliative chemotherapy in patients with metastatic PDAC. This could facilitate personalized treatment of patients with metastatic PDAC.


Assuntos
Carcinoma Ductal Pancreático , Ácidos Nucleicos Livres , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Prognóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regiões Promotoras Genéticas , Ácidos Nucleicos Livres/uso terapêutico , Proteínas de Membrana/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Neoplasias Pancreáticas
4.
Front Psychol ; 13: 928217, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783754

RESUMO

Purpose: In the introduction of new technologies into organizations, there has been an increasing trend to recruit and make use of the so-called "super users" to help ensure the future use of the technology in question. Little is known about the criteria that should ideally be considered in the selection of these super users, or about the best way to carve up the roles and responsibilities in this process between super users and middle management. In this study, we investigated (1) which criteria should be emphasized in the selection of super users, and (2) how middle management and super users understand and negotiate the responsibilities of their respective roles during implementation of technological change. Methods: We conducted 10 individual semi-structured interviews and used thematic analysis of this data set to identify selection criteria, roles, and responsibilities. Results: We found that the main selection criteria for super users should be: (1) availability and local knowledge, (2) technological skills, (3) pedagogical skills, and (4) proactiveness. The main roles and responsibilities that should be carved up between management and super users can be grouped into two overarching categories, each with several subcategories. Within the Learning culture category, the responsibilities are to (1) facilitate collective learning, (2) engage with criticism, and (3) promote collective sharing; and within the Individual learning category, to (4) facilitate individual learning, (5) provide instrumental support, and (6) provide emotional support. Discussion and Conclusion: Based on the findings, we propose a conceptual model of technological implementation and the construction of a culture of organizational learning, entitled ECo-System Of Learning in Organizations (ECSO-Learn); we additionally show how a learning agent (previously known as a super user) can be recruited to best fit into this model of long-term organizational learning.

5.
Pancreatology ; 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33994313

RESUMO

BACKGROUND: We recently identified a diagnostic prediction model based on promoter hypermethylation of eight selected genes in plasma cell-free (cf) DNA, which showed promising results as a diagnostic biomarker for pancreatic ductal adenocarcinoma (PDAC). The aim of the present study was to validate this biomarker profile in an external patient cohort and examine any additional effect of serum CA 19-9. METHODS: Patients with PDAC (n = 346, stage I-IV) and chronic pancreatitis (n = 25) were included. Methylation-specific PCR of a 28-gene panel was performed on serum cfDNA samples. The previously developed diagnostic prediction model (age>65 years, BMP3, RASSF1A, BNC1, MESTv2, TFPI2, APC, SFRP1 and SFRP2) was validated alone and in combination with serum CA 19-9 in this external patient cohort. RESULTS: Patients with PDAC had a higher number of hypermethylated genes (mean 8.11, 95% CI 7.70-8.52) than patients with chronic pancreatitis (mean 5.60, 95% CI 4.42-6.78, p = 0.011). Validation of the diagnostic prediction model yielded an AUC of 0.77 (95% CI 0.69-0.84). The combination of serum CA 19-9 and our test had an AUC of 0.93 (95% CI 0.89-0.96) in the primary study and 0.85 (95% CI 0.79-0.91) in the validation study. CONCLUSION: In this validation study, PDAC was associated with a higher number of hypermethylated genes in serum cfDNA than chronic pancreatitis. Our diagnostic test was superior to the predictive value of serum CA 19-9 alone in both the primary and the validation study. The combination of our test with CA 19-9 may serve as a clinically useful diagnostic biomarker for PDAC.

6.
Appl Physiol Nutr Metab ; 46(9): 1133-1142, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33740389

RESUMO

The effect of oral glutathione (GSH) supplementation was studied in obese subjects with and without type 2 diabetes (T2DM) on measures of glucose homeostasis and markers of oxidative stress. Twenty subjects (10 patients with T2DM and 10 obese subjects) were recruited for the study, and randomized in a double-blinded placebo-controlled manner to consume either 1000 mg GSH per day or placebo for 3 weeks. Before and after the 3 weeks insulin sensitivity was measured with the hyperinsulinemic-euglycemic clamp and a muscle biopsy was obtained to measure GSH and skeletal muscle mitochondrial hydrogen peroxide (H2O2) emission rate. Whole body insulin sensitivity increased significantly in the GSH group. Skeletal muscle GSH was numerically increased (∼19%) in the GSH group; no change was seen in GSH to glutathione disulfide ratio. Skeletal muscle mitochondrial H2O2 emission rate did not change in response to the intervention and neither did the urinary excretion of the RNA oxidation product 8-oxo-7,8-dihydroguanosine or the DNA oxidation product 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), although 8-oxodG decreased as a main effect of time. Oral GSH supplementation improves insulin sensitivity in obese subjects with and without T2DM, although it does not alter markers of oxidative stress. The study has been registered in clinicaltrials.gov (NCT02948673). Novelty: Reduced glutathione supplementation increases insulin sensitivity in obese subjects with and without T2DM. H2O2 emission rate from skeletal muscle mitochondria was not affected by GSH supplementation.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Suplementos Nutricionais , Glutationa/administração & dosagem , Resistência à Insulina/fisiologia , Obesidade/fisiopatologia , Administração Oral , Biomarcadores/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Nutricionais/efeitos adversos , Teste de Tolerância a Glucose , Glutationa/efeitos adversos , Glutationa/sangue , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Pessoa de Meia-Idade , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Estresse Oxidativo , Consumo de Oxigênio
7.
Front Immunol ; 11: 1968, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849657

RESUMO

Immune surveillance of cancer cells is facilitated by the Natural Killer Group 2D (NKG2D) receptor expressed by different lymphocyte subsets. It recognizes NKG2D ligands that are rarely expressed on healthy cells, but upregulated by tumorigenesis, presenting a target for immunological clearance. The molecular mechanisms responsible for NKG2D ligand regulation remain complex. Here we report that cancer cell metabolism supports constitutive surface expression of the NKG2D ligand MHC class I chain-related proteins A (MICA). Knockout of the N-glycosylation gene N-acetylglucosaminyltransferase V (MGAT5) in HEK293 cells induced altered metabolism and continuous high MICA surface expression. MGAT5 knockout cells were used to examine the association of cell metabolism and MICA expression through genetic, pharmacological and metabolic assays. Findings were verified in cancer cell lines. Cells with constitutive high MICA expression showed enhanced spare respiratory capacity and elevated mitochondrial efflux of citrate, determined by extracellular flux analysis and metabolomics. MICA expression was reduced by inhibitors of mitochondrial function, FCCP and etomoxir e.g., and depended on conversion of citrate to acetyl-CoA and oxaloacetate by ATP citrate lyase, which was also observed in several cancer cell types. Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) analysis revealed that upregulated MICA transcription was associated with an open chromatin structure at the MICA transcription start site. We identify mitochondria and cytoplasmic citrate as key regulators of constitutive MICA expression and we propose that metabolic reprogramming of certain cancer cells facilitates MICA expression and NKG2D-mediated immune recognition.


Assuntos
Ácido Cítrico/metabolismo , Citoplasma/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Imunomodulação , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina , Feminino , Edição de Genes , Regulação da Expressão Gênica , Glicólise , Células HEK293 , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Ligantes , Ativação Linfocitária , Linfócitos/imunologia , Linfócitos/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Biológicos , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Ligação Proteica , Sítio de Iniciação de Transcrição
8.
J Sleep Res ; 29(1): e12901, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31515853

RESUMO

Insomnia Disorder is the most prevalent sleep disorder, and it involves both sleep difficulties and daytime complaints. The neural underpinnings of Insomnia Disorder are poorly understood. Several existing neuroimaging studies focused on local measures and specific regions of interests, which makes it difficult to judge their whole-brain significance. We therefore here applied a data-driven approach to assess differences in whole-brain structural connectivity between adults with Insomnia Disorder and matched controls without sleep complaints. We used diffusion tensor imaging and probabilistic tractography to assess whole-brain structural connectivity, and examined group differences using network-based statistics. The results revealed a significant difference in the structural connectivity of the two groups (p = .014). Participants with Insomnia Disorder showed reduced connectivity in a sub-network that included mainly fronto-subcortical connections with the insula as a key region. By taking a whole-brain network perspective, our study enables the integration of previous inconsistent findings. Our results reveal that reduced structural connectivity of the left insula and the connections between frontal and subcortical regions are central neurobiological features of Insomnia Disorder. The importance of these areas for interoception, emotional processing, stress responses and the generation of slow-wave sleep may help guide the development of neurobiology-based models of the prevalent condition of Insomnia Disorder.


Assuntos
Imagem de Tensor de Difusão/métodos , Vias Neurais/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Physiol ; 598(4): 731-754, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31710095

RESUMO

KEY POINTS: This is the first long-term human clinical trial to report on effects of nicotinamide riboside (NR) on skeletal muscle mitochondrial function, content and morphology. NR supplementation decreases nicotinamide phosphoribosyltransferase (NAMPT) protein abundance in skeletal muscle. NR supplementation does not affect NAD metabolite concentrations in skeletal muscle. Respiration, distribution and quantity of muscle mitochondria are unaffected by NR. NAMPT in skeletal muscle correlates positively with oxidative phosphorylation Complex I, sirtuin 3 and succinate dehydrogenase. ABSTRACT: Preclinical evidence suggests that the nicotinamide adenine dinucleotide (NAD+ ) precursor nicotinamide riboside (NR) boosts NAD+ levels and improves diseases associated with mitochondrial dysfunction. We aimed to determine if dietary NR supplementation in middle-aged, obese, insulin-resistant men affects mitochondrial respiration, content and morphology in skeletal muscle. In a randomized, placebo-controlled clinical trial, 40 participants received 1000 mg NR or placebo twice daily for 12 weeks. Skeletal muscle biopsies were collected before and after the intervention. Mitochondrial respiratory capacity was determined by high-resolution respirometry on single muscle fibres. Protein abundance and mRNA expression were measured by Western blot and quantitative PCR analyses, respectively, and in a subset of the participants (placebo n = 8; NR n = 8) we quantified mitochondrial fractional area and mitochondrial morphology by laser scanning confocal microscopy. Protein levels of nicotinamide phosphoribosyltransferase (NAMPT), an essential NAD+ biosynthetic enzyme in skeletal muscle, decreased by 14% with NR. However, steady-state NAD+ levels as well as gene expression and protein abundance of other NAD+ biosynthetic enzymes remained unchanged. Neither respiratory capacity of skeletal muscle mitochondria nor abundance of mitochondrial associated proteins were affected by NR. Moreover, no changes in mitochondrial fractional area or network morphology were observed. Our data do not support the hypothesis that dietary NR supplementation has significant impact on skeletal muscle mitochondria in obese and insulin-resistant men. Future studies on the effects of NR on human skeletal muscle may include both sexes and potentially provide comparisons between young and older people.


Assuntos
Resistência à Insulina , Mitocôndrias Musculares/fisiologia , Músculo Esquelético/fisiologia , Niacinamida/análogos & derivados , Obesidade/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , NAD/metabolismo , Niacinamida/administração & dosagem , Nicotinamida Fosforribosiltransferase/metabolismo , Compostos de Piridínio
10.
Br J Nutr ; 122(12): 1409-1416, 2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31566157

RESUMO

Fe deficiency (ID) defined as plasma ferritin <12 µg/l is associated with delayed cognitive development in early childhood and increased incidence of infections; however, the longitudinal association between early-life factors and ID in 18-month-old children in Denmark is unknown. The present study aimed to determine the prevalence of ID and to describe risk factors associated with ID in healthy 18-month-old Danish children. Blood samples, anthropometric measurements and self-reported questionnaire data had been obtained in the birth cohort, Odense Child Cohort. The questionnaires were modified from those used in the Danish National Birth Cohort. Plasma ferritin and C-reactive protein in venous, non-fasting samples were analysed in the final sample size of 370 children after exclusion of seventy-nine children due to chronic disease, acute infection, C-reactive protein >10 mg/l, twin birth or prematurity. Associations with ID were analysed by logistic regression, adjusting for sex, maternal education, duration of partial breast-feeding and current intake of milk, fish and meat. Overall, fifty-six children had ID (15·1 %). Factors associated with increased risk were exclusive breast-feeding beyond 4 months (OR 5·97; 95 % CI 1·63, 21·86) and no intake of oral Fe supplements from 6 to 12 months (OR 3·99, 95 % CI 1·33, 11·97. Duration of partial breast-feeding and current diet was not associated with ID. In conclusion, the ID prevalence was 15·1 %, and both exclusive breast-feeding beyond 4 months and no intake of oral Fe supplements from 6 to 12 months were associated with increased risk of ID in 18-month-old children.


Assuntos
Anemia Ferropriva/epidemiologia , Anemia Ferropriva/etiologia , Aleitamento Materno , Suplementos Nutricionais , Antropometria , Dinamarca/epidemiologia , Dieta , Feminino , Ferritinas/sangue , Humanos , Lactente , Ferro/sangue , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários
11.
Nat Struct Mol Biol ; 25(7): 631-640, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29967540

RESUMO

Ubiquitination is a post-translational modification (PTM) that is essential for balancing numerous physiological processes. To enable delineation of protein ubiquitination at a site-specific level, we generated an antibody, denoted UbiSite, recognizing the C-terminal 13 amino acids of ubiquitin, which remain attached to modified peptides after proteolytic digestion with the endoproteinase LysC. Notably, UbiSite is specific to ubiquitin. Furthermore, besides ubiquitination on lysine residues, protein N-terminal ubiquitination is readily detected as well. By combining UbiSite enrichment with sequential LysC and trypsin digestion and high-accuracy MS, we identified over 63,000 unique ubiquitination sites on 9,200 proteins in two human cell lines. In addition to uncovering widespread involvement of this PTM in all cellular aspects, the analyses reveal an inverse association between protein N-terminal ubiquitination and acetylation, as well as a complete lack of correlation between changes in protein abundance and alterations in ubiquitination sites upon proteasome inhibition.


Assuntos
Lisina/química , Ubiquitina/imunologia , Ubiquitina/metabolismo , Ubiquitinação , Especificidade de Anticorpos , Sítios de Ligação , Linhagem Celular , Humanos , Células Jurkat , Espectrometria de Massas , Proteoma/química , Proteoma/metabolismo , Ubiquitina/química
12.
J Fish Biol ; 93(2): 334-343, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30051481

RESUMO

In the western Baltic Sea (WBS), whiting Merlangius merlangus is the main piscivorous fish together with cod Gadus morhua. In the present study, we investigate the growth and food consumption rates of WBS M. merlangus and compare the growth rates of males and females with those of M. merlangus in the North Sea (NS). Food consumption rates are estimated directly from sampled stomach contents in the WBS using a gastric evacuation rate model and indirectly by using a static energy-budget model together with the growth rates. The results indicate that male and female M. merlangus in the WBS have similar feeding and growth strategies, while in the NS M. merlangus show more pronounced differences in food consumption and growth dynamics between the sexes. Female WBS M. merlangus grow significantly slower than their conspecifics in the NS, but there is no significant difference for males. Sexual size dimorphism is seen in both areas, but for M. merlangus in the WBS the difference is less pronounced. Food consumption rates in the WBS differ between seasons, with the lowest food intake in the first 2 quarters of the year and the highest in the 3rd quarter. No differences in consumption rates were seen between males and females, which could be related to the more similar growth pattern seen for M. merlangus in the WBS.


Assuntos
Ingestão de Alimentos , Gadiformes/crescimento & desenvolvimento , Animais , Feminino , Peixes , Conteúdo Gastrointestinal , Masculino , Modelos Biológicos , Mar do Norte , Estações do Ano , Caracteres Sexuais
13.
Eur J Sport Sci ; 16(7): 801-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26744809

RESUMO

Actovegin, a deproteinized haemodialysate of calf blood, is suggested to have ergogenic properties, but this potential effect has never been investigated in human skeletal muscle. To investigate this purported ergogenic effect, we measured the mitochondrial respiratory capacity in permeabilized human skeletal muscle fibres acutely exposed to Actovegin in a low and in a high dose. We found that Actovegin, in the presence of complex I-linked substrates increased the oxidative phosphorylation (OXPHOS) capacity significantly in a concentration-dependent manner (19 ± 3, 31 ± 4 and 45 ± 4 pmol/mg/s). Maximal OXPHOS capacity with complex I and II-linked substrate was increased when the fibres were exposed to the high dose of Actovegin (62 ± 6 and 77 ± 6 pmol/mg/s) (p < .05). The respiratory capacity of the electron transfer system as well as Vmax and Km were also increased in a concentration-dependent manner after Actovegin exposure (70 ± 6, 79 ± 6 and 88 ± 7 pmol/mg/s; 13 ± 2, 25 ± 3 and 37 ± 4 pmol/mg/s; 0.08 ± 0.02, 0.21 ± 0.03 and 0.36 ± 0.03 mM, respectively) (p < .05). In summary, we report for the first time that Actovegin has a marked effect on mitochondrial oxidative function in human skeletal muscle. Mitochondrial adaptations like this are also seen after a training program in human subjects. Whether this improvement translates into an ergogenic effect in athletes and thus reiterates the need to include Actovegin on the World Anti-Doping Agency's active list remains to be investigated.


Assuntos
Heme/análogos & derivados , Mitocôndrias Musculares/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Adulto , Dopagem Esportivo , Heme/administração & dosagem , Heme/farmacocinética , Heme/farmacologia , Humanos , Pessoa de Meia-Idade , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Respiração/efeitos dos fármacos
14.
Future Oncol ; 10(2): 277-83, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24490613

RESUMO

Ewing's sarcoma (EWS) is a highly malignant cancer in children, adolescents and young adults. The chemotherapy required to treat female EWS patients may cause primary ovarian insufficiency and infertility as a side effect. Cryopreservation of ovarian tissue before the start of chemotherapy can potentially preserve fertility. When the patient has been cured and primary ovarian insufficiency has developed, transplantation of frozen/thawed ovarian tissue can restore ovarian function. The tissue is usually collected before chemotherapy is initiated, and malignant cells may contaminate the stored ovarian tissue, potentially causing recrudescence of the original cancer after transplantation. The risk of EWS metastasizing to the ovary is probably low but has not been studied in great detail. This review describes the available evidence on the risk of malignant cell contamination in the ovaries of EWS patients and presents a new case of malignant cells in an ovarian biopsy from a girl with EWS.


Assuntos
Criopreservação , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Ovário/transplante , Sarcoma de Ewing/complicações , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Feminino , Humanos , Recidiva Local de Neoplasia , Inoculação de Neoplasia , Neoplasias Ovarianas/secundário , Radioterapia/efeitos adversos , Risco , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/patologia
15.
Int J Sports Phys Ther ; 9(1): 82-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24567859

RESUMO

PURPOSE/BACKGROUND: Muscle soreness can negatively interfere with the activities of daily living as well as sports performance. In the working environment, a common problem is muscle tenderness, soreness and pain, especially for workers frequently exposed to unilateral high repetitive movements tasks. The aim of the study is therefore to investigate the acute effect of massage applied using a simple device Thera-band roller Massager on laboratory induced hamstring muscle soreness, and the potential cross over effect to the non-massaged limb. METHODS: 22 healthy untrained men (Mean age 34 +/- 7 years; mean height 181.7 +/- 6.9 cm; mean weight 80.6 +/- 6.4 kg; BMI: 24.5 +/- 1.3) with no prior history of knee, low back or neck injury or other adverse health issues were recruited. Participants visited the researchers on two separate occasions, separated by 48 hours, each time providing a soreness rating (modified visual analog scale 0-10), and being tested for pressure pain threshold (PPT) and active range of motion (ROM) of the hamstring muscles. During the first visit, delayed onset muscular soreness of the hamstring muscles was induced by 10 x 10 repetitions of the stiff-legged dead-lift. On the second visit participants received either 1) 10 minutes of roller massage on one leg, while the contralateral leg served as a cross over control, or 2) Resting for 10 minutes with no massage at all. Measurement of soreness, PPT and ROM were taken immediately before and at 0, 10, 30 and 60 min. after treatment. RESULTS: There was a significant group by time interaction for soreness (p < 0.0001) and PPT (p = 0.0007), with the massage group experiencing reduced soreness and increasing PPT compared with the control group. There was no group by time interaction for ROM (p = 0.18). At 10 min. post massage there was a significant reduction in soreness of the non-massaged limb in the cross over control group compared to controls but this effect was lost 30 minutes post massage. CONCLUSION: Massage with a roller device reduces muscle soreness and is accompanied by a higher PPT of the affected muscle. LEVEL OF EVIDENCE: 2c; outcomes research.

16.
Artigo em Inglês | MEDLINE | ID: mdl-23726938

RESUMO

Haemoglobin polymorphism in cod (Gadus morhua L) has been investigated throughout the last 50years. Field studies have shed light on the geographic distribution of the two common alleles (HbI(1) and HbI(2)), and laboratory studies have shown effects of genotype on physiological traits such as growth, reproduction and hypoxia tolerance. The geographic distribution of alleles shows a correlation with temperature, with increasing frequency of HbI(1) in warmer areas. This is likely due to temperature-related differences in oxygen affinity of the three genotypes. We provide a general ecological introduction to cod haemoglobin polymorphism and a detailed discussion of physiological studies, particularly laboratory growth studies. Although differences in oxygen uptake are almost certainly a contributory mechanism to observed differences in traits such as growth rate, many other environmental, behavioural and social factors may also contribute, making it difficult to quantify the effect of HbI either experimentally or in the field.


Assuntos
Gadus morhua/genética , Gadus morhua/fisiologia , Geografia , Hemoglobinas/genética , Animais , Transporte Biológico , Gadus morhua/crescimento & desenvolvimento , Frequência do Gene/genética , Genótipo , Hipóxia/fisiopatologia , Noruega , Oceanos e Mares , Oxigênio/metabolismo , Temperatura
17.
Blood ; 120(22): 4311-6, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22709693

RESUMO

Some women suffering from leukemia require bone marrow transplantation to be cured. Bone marrow transplantation is associated with a high risk of sterility, and some patients are offered fertility preservation by cryopreservation of the ovarian cortex. Transplantation of the ovarian cortex to women cured of leukemia who became menopausal is currently not performed because of the risk of introducing the disease. In this study, individual pieces of ovarian cortex intended for reimplantation from 25 patients with leukemia were transplanted to each of 25 nude mice for 20 weeks. The ovarian cortex was examined before and after transplantation by histology and immunohistochemistry, and RT-quantitative PCR (in the 7 patients with a known marker). Seventeen patients had the ovarian cortex retrieved when they were in complete remission. Before transplantation, 4 of 7 pieces (2 from patients in complete remission) of ovarian cortex had a positive RT-quantitative PCR. After transplantation, none of the mice revealed any sign of disease, neither in the pieces of ovarian cortex transplanted nor in any of the murine organs evaluated. Thus, the ovaries from patients in complete remission do not appear to contain viable malignant cells contrasting ovarian tissue retrieved before treatment.


Assuntos
Leucemia/patologia , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/patologia , Ovário/patologia , Adolescente , Adulto , Animais , Sobrevivência Celular , Criança , Pré-Escolar , Criopreservação/métodos , Feminino , Preservação da Fertilidade/métodos , Preservação da Fertilidade/normas , Humanos , Leucemia/terapia , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/fisiologia , Ovário/transplante , Indução de Remissão , Transplante Heterólogo , Adulto Jovem
18.
Comp Immunol Microbiol Infect Dis ; 33(6): e99-e103, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21094422
19.
Pharmacogenet Genomics ; 17(7): 555-67, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17558311

RESUMO

OBJECTIVES: The purinergic P2RX7 receptor (P2RX7) has been shown to play a role in the regulation of osteoblast and osteoclast activity. The aim of this study was to determine the presence of polymorphisms in exon 13 of the P2X7 gene and the association with osteoclast apoptosis in vitro and bone status in vivo. METHODS: A total of 1764 postmenopausal women were genotyped for three single nucleotide polymorphisms detected after sequencing of exon 13 of P2X7. Bone markers, bone mineral density of the hip and lumbar spine were determined at baseline and after 10 years, and vertebral fracture incidence after 10 years. In-vitro ATP-induced caspase-1 determinations were performed on osteoclasts from the different genotypes. RESULTS: Three polymorphisms were detected (Gln460Arg, Glu496Ala, and Ile568Asn). None of the polymorphisms was related to bone mineral density or changes in bone mineral density over 10 years in hormone replacement therapy naïve women. The Ile568Asn polymorphism was however, associated with effect of hormone replacement therapy. Furthermore, the 10-year fracture incidence was significantly associated with both the Glu496Ala and the Ile568Asn. The Glu496Ala polymorphism was closely related to ATP-induced osteoclast apoptosis in vitro, as osteoclasts from individuals homozygous for the C allele had significantly decreased apoptotic activity. CONCLUSION: The P2X7 Glu496Ala and the Ile568Asn single nucleotide polymorphisms are associated with 10-year fracture risk in postmenopausal women and response to hormone replacement therapy treatment. Further, the Glu496Ala polymorphism is strongly influencing osteoclast apoptosis in vitro, which could contribute to increased fracture risk.


Assuntos
Fraturas Ósseas/genética , Receptores Purinérgicos P2/genética , Trifosfato de Adenosina/farmacologia , Apoptose/efeitos dos fármacos , Sequência de Bases , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/genética , Primers do DNA/genética , Terapia de Reposição de Estrogênios , Éxons , Feminino , Fraturas Ósseas/etiologia , Fraturas Ósseas/metabolismo , Genótipo , Haplótipos , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Farmacogenética , Polimorfismo de Nucleotídeo Único , Receptores Purinérgicos P2X7 , Fatores de Risco , Fatores de Tempo
20.
J Ultrasound Med ; 20(10): 1047-52, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11587011

RESUMO

OBJECTIVE: To evaluate the influence of maternal weight and the orientation of the fetal 4-chamber heart view on the detection of a fetal echogenic cardiac focus. METHODS: In this nested case-control study, 103 women undergoing anatomic surveys at 15 to 22 weeks between January 1, 1997, and June 15, 1999, were identified as having an echogenic cardiac focus via our computerized database. A control group was selected from among the same group of patients. Data were collected from the sonography reports, prenatal records, and sonographic images of 4-chamber heart views; maternal characteristics and sonographic details were recorded, including the orientation of the 4-chamber view (apical, basilar, and right and left lateral). RESULTS: Gravidas in the echogenic cardiac focus group were more likely to be of lower weight (68.0 +/- 14.4 versus 72.9 +/- 18.3 kg; P = .04), of lower body mass index (25.5 +/- 5.3 versus 27.3 +/- 6.2 kg/m2; P = .03), of younger age (24.4 +/- 6.5 versus 26.9 +/- 6.9 years; P = .01), and African American or Asian (37.9% versus 27.2% and 9.7% versus 2%; P = .01). Cases were scanned at earlier gestational ages (18.9 +/- 1.6 versus 19.5 +/- 1.7 weeks; P = .01). The focus group was more likely to have had an apical view of the fetal heart taken (80.8% versus 51.4%; P = .0001). Controls were more likely to have had a right lateral view taken (44.6% versus 20.8%; P = .002). No significant difference was found between groups in terms of any other maternal or sonographic variable studied. CONCLUSIONS: The echogenic cardiac focus group was more likely to have a lower body mass index and to be scanned with the apical fetal heart view. The orientation of the fetal 4-chamber heart view exerted the most statistically significant influence on detection rates for the echogenic cardiac focus, implying that the more technically facile the sonographic study, the more likely an echogenic cardiac focus will be found.


Assuntos
Peso Corporal/fisiologia , Coração Fetal/diagnóstico por imagem , Gravidez/fisiologia , Ultrassonografia Pré-Natal/métodos , Fatores Etários , População Negra , Estudos de Casos e Controles , Feminino , Coração Fetal/fisiologia , Idade Gestacional , Humanos , Modelos Logísticos , Fatores de Risco
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