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1.
Tijdschr Psychiatr ; 64(9): 604-607, 2022.
Artigo em Holandês | MEDLINE | ID: mdl-36349857

RESUMO

BACKGROUND: In 2018 Jellinek became a smoke free institution. By implementing ‘Jellinek Smoke free’ in all locations (15), a policy has been implemented to facilitate smoking cessation in clients with a comorbid tobacco use disorder seeking treatment for substance use disorders at Jellinek. AIM: To investigate whether the implementation of the new policy impacted smoking behaviour of clients in treatment for substance use disorders at Jellinek. METHOD: Based on data from anonymized client files, changes in smoking behaviour (cessation or reduction) were analysed for clients with other addictions who started treatment in 2016 versus clients who started in 2019 - after the implementation of the new smoke free policy. Comparative analyses were conducted on the population as a whole, per type of treatment (outpatient care, residential care, Minnesota, outreaching care) as well as per type of smoker (light, moderate, heavy). RESULTS: In the client population as a whole, significantly more people stopped smoking in 2019 (22%) in comparison to 2016 (16%) and there was a trend toward statistical significance with regard to reduction. When a cessation period was part of treatment, significantly more clients stopped and decreased the number of cigarettes a day. Moreover, light and moderate smokers (≤ 20 cigarettes a day) stopped and reduced significantly more in 2019 (32%) than in 2016 (23%). In outpatient care, outreaching care and with heavy smokers (> 20 cigarettes a day), there was no significant difference in percentage of cessation and reduction between 2016 and 2019. CONCLUSION: After implementing Jellinek Smoke free, significant changes in smoking behaviour occurred in the client population as a whole with a comorbid tobacco use disorder, in treatments where a cessation period was part of treatment as well as with light and moderate smokers.


Assuntos
Política Antifumo , Abandono do Hábito de Fumar , Transtornos Relacionados ao Uso de Substâncias , Tabagismo , Humanos , Tabagismo/epidemiologia , Tabagismo/terapia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/terapia , Fumar/epidemiologia , Fumar/terapia
2.
J Dairy Sci ; 104(7): 8152-8163, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33896624

RESUMO

Overconditioning is a risk factor for upregulated pre- and postpartum fat mobilization. Therefore, we hypothesized that overconditioning at the end of pregnancy leads to the accumulation of lipids in the liver and modifications of the hepatic gene expression pattern. The aim of this study was to evaluate the effect of normal- versus overconditioning on the hepatic transcriptomic profile of dairy cows at the end of pregnancy. Ten dry multiparous Holstein cows were killed 2 wk before expected calving. Body condition score (BCS) and backfat thickness (BFT) were evaluated, and blood samples for nonesterified fatty acids (NEFA) were taken before cows were killed. After cows were killed, liver biopsy samples were collected for further assessment of total lipids and RNA sequencing. Five cows were classified as normal-conditioned (median BCS = 3, range 2.75-3.5) and 5 as overconditioned (median BCS = 4, range 4-5). Regression models confirmed that normal-conditioned cows had lower BFT (1.29 ± 0.29 cm; least squares means ± standard error) and serum NEFA (0.16 ± 0.04 mmol/L) in comparison to overconditioned cows (3.14 ± 0.43 cm and 0.38 ± 0.07 mmol/L for BFT and NEFA, respectively). Total liver lipid percentage tended to be lower in normal- versus overconditioned cows (4.63 ± 0.40% and 6.06 ± 0.44%, respectively). In comparison to the mean liver lipid percentage of the normal- and overconditioned cows, 1 overconditioned cow had a relatively low (5.21%) and 1 normal-conditioned cow had a relatively high (6.07%) liver lipid percentage. Differentially expressed genes analysis (edgeR quasi-likelihood method) showed that normal-conditioned cows presented 11 upregulated and 12 downregulated genes in comparison to overconditioned cows. Linear discriminant analysis effects size revealed 133 differentially expressed genes between normal- versus overconditioned cows. Notably, the liver of normal-conditioned cows had upregulated genes associated with liver functionality (ALB, SELENOP, IGF1, and IGF2). On the other hand, overconditioned cows had upregulated genes associated with the acute-phase response (C3, HPX, and, LBP). High basal lipolysis in overconditioned cows at the end of pregnancy increased liver lipid content, and this may alter the hepatic gene expression pattern to a pro-inflammatory state.


Assuntos
Lactação , Período Pós-Parto , Animais , Bovinos , Dieta , Ácidos Graxos não Esterificados , Feminino , Expressão Gênica , Fígado , Leite , Gravidez
3.
Nature ; 506(7489): 445-50, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24553142

RESUMO

Ependymomas are common childhood brain tumours that occur throughout the nervous system, but are most common in the paediatric hindbrain. Current standard therapy comprises surgery and radiation, but not cytotoxic chemotherapy as it does not further increase survival. Whole-genome and whole-exome sequencing of 47 hindbrain ependymomas reveals an extremely low mutation rate, and zero significant recurrent somatic single nucleotide variants. Although devoid of recurrent single nucleotide variants and focal copy number aberrations, poor-prognosis hindbrain ependymomas exhibit a CpG island methylator phenotype. Transcriptional silencing driven by CpG methylation converges exclusively on targets of the Polycomb repressive complex 2 which represses expression of differentiation genes through trimethylation of H3K27. CpG island methylator phenotype-positive hindbrain ependymomas are responsive to clinical drugs that target either DNA or H3K27 methylation both in vitro and in vivo. We conclude that epigenetic modifiers are the first rational therapeutic candidates for this deadly malignancy, which is epigenetically deregulated but genetically bland.


Assuntos
Ilhas de CpG/genética , Ependimoma/genética , Epigênese Genética/genética , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Metilação de DNA/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Ependimoma/tratamento farmacológico , Epigenômica , Feminino , Regulação Neoplásica da Expressão Gênica , Inativação Gênica/efeitos dos fármacos , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Lactente , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação/genética , Fenótipo , Complexo Repressor Polycomb 2/metabolismo , Prognóstico , Rombencéfalo/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Dairy Sci ; 103(7): 6392-6406, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32331880

RESUMO

The aim of this study was to detect the genomic region or regions associated with metabolic clusters in early-lactation Holstein cows. This study was carried out in 2 experiments. In experiment I, which was carried out on 105 multiparous Holstein cows, animals were classified through k-means clustering on log-transformed and standardized concentrations of blood glucose, insulin-like growth factor I, free fatty acids, and ß-hydroxybutyrate at 14 and 35 d in milk (DIM), into metabolic clusters, either balanced (BAL) or other (OTR). Forty percent of the animals were categorized in the BAL group, and the remainder were categorized as OTR. The cows were genotyped for a total of 777,962 SNP. A genome-wide association study was performed, using a case-control approach through the GEMMA software, accounting for population structure. We found 8 SNP (BTA11, BTA23, and BTAX) associated with the predicted metabolic clusters. In experiment II, carried out on 4,267 second-parity Holstein cows, milk samples collected starting from the first week until 50 DIM were used to determine Fourier-transform mid-infrared (FT-MIR) spectra and subsequently to classify the animals into the same metabolic clusters (BAL vs. OTR). Twenty-eight percent of the animals were categorized in the BAL group, and the remainder were classified in the OTR category. Although daily milk yield was lower in BAL cows, we found no difference in daily fat- and protein-corrected milk yield in cows from the BAL metabolic cluster compared with those in the OTR metabolic cluster. In the next step, a single-step genomic BLUP was used to identify the genomic region(s) associated with the predicted metabolic clusters. The results revealed that prediction of metabolic clusters is a highly polygenic trait regulated by many small-sized effects. The region of 36,258 to 36,295 kb on BTA27 was the highly associated region for the predicted metabolic clusters, with the closest genes to this region (ANK1 and miR-486) being related to hematopoiesis, erythropoiesis, and mammary gland development. The heritability for metabolic clustering was 0.17 (SD 0.03), indicating that the use of FT-MIR spectra in milk to predict metabolic clusters in early-lactation across a large number of cows has satisfactory potential to be included in genetic selection programs for modern dairy cows.


Assuntos
Bovinos/metabolismo , Regulação da Expressão Gênica/fisiologia , Estudo de Associação Genômica Ampla , Lactação/fisiologia , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/metabolismo , Estudos de Casos e Controles , Análise por Conglomerados , Ácidos Graxos não Esterificados/sangue , Feminino , Leite/química , Proteínas do Leite/análise , Gravidez
5.
Breast Cancer Res Treat ; 174(3): 649-659, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30610490

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) has been implicated as an important step in the development of distant metastases. We therefore wished to study EMT status of primary breast carcinomas from patients who during follow-up developed distant metastases. METHODS: mRNA expression profiles of primary breast carcinoma samples (n = 151) from patients who developed metastatic disease were analyzed and EMT status was designated using a previously described EMT-core signature. EMT status of the primary tumor was correlated to clinicopathological characteristics, molecular subtypes, metastasis pattern, chemotherapy response and survival outcomes. In addition, using immunohistochemistry, the expression levels of several proteins implicated in EMT were studied (CDH1, CDH2, NAT1, SNAI2, TWIST1, VIM, and ZEB1) compared with the designated EMT status and survival. RESULTS: Utilizing the 130-gene-EMT-core signature, 66.2% of the primary tumors in the current study was assessed as EMT-activated. In contrast to our expectations, analyses revealed that 84.6% of Luminal A tumors, 65.1% of Luminal B tumors, and 55.6% of HER2-like had an activated EMT status, compared to only 25% of the basal-type tumors (p < 0.001). EMT status was not correlated to the pattern of metastatic disease, metastasis-specific survival, and overall survival. Similarly, there was not a significant association between EMT status of the primary tumor and chemotherapy response in the metastatic setting. Immunostaining for NAT1 and TWIST1 correlated with the EMT status (p 0.003 and p 0.047, respectively). Multivariate analyses showed that NAT1 and TWIST1 staining was significantly associated with EMT status regardless of the estrogen receptor status of the tumors (p values: 0.020 and 0.027, respectively). CONCLUSIONS: The EMT status of breast cancers, as defined by the presence of a core EMT gene expression signature is associated with non-basal-type tumors, but not with the pattern of distant metastasis. Of several potential immunohistochemical EMT markers, only NAT1 and TWIST1 expression levels were associated with the gene expression-based EMT status.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Perfilação da Expressão Gênica/métodos , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica
6.
BMC Cancer ; 19(1): 333, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30961553

RESUMO

BACKGROUND: Visceral organ metastasis is associated with poor survival outcomes in terms of metastasis free- and overall survival in breast carcinomas. Identification of a gene expression profile in tumours that selects a subpopulation of patients that is more likely to develop visceral organ metastases will help elucidate mechanisms for the development of distant metastases and could be of clinical value. With this study we aimed to determine genomic predictors that would help to distinguish breast cancer patients with more likelihood to develop visceral metastasis. METHODS: Gene expression profiling data of 157 primary tumours from breast cancer patients who developed distant metastases were analyzed and differentially expressed genes between the group of tumours with visceral metastasis and the those without visceral metastases were identified. Published data were used to validate our findings. Multivariate logistic regression tests were applied to further investigate the association between the gene-expression-signature and clinical variables. Survival analyses were performed by the Kaplan-Meier method. RESULTS: Fourteen differentially expressed genes (WDR6, CDYL, ATP6V0A4, CHAD, IDUA, MYL5, PREP, RTN4IP1, BTG2, TPRG1, ABHD14A, KIF18A, S100PBP and BEND3) were identified between the group of tumours with and without visceral metastatic disease. Five of these genes (CDYL, ATP6V0A4, PREP, RTN4IP1 and KIF18A) were up-regulated and the other genes were down-regulated. This gene expression signature was validated in the training and in the independent data set (p 2.13e- 08 and p 9.68e- 06, respectively). Multivariate analyses revealed that the 14-gene-expression-signature was associated with visceral metastatic disease (p 0.001, 95% CI 1.43-4.27), independent of other clinicopathologic features. This signature has been also found to be associated with survival status of the patients (p < .001). CONCLUSION: We have identified an unique gene expression signature which is specific to visceral metastasis. This 14-gene-expression-signature may play a role in identifying the subgroup of patients with potential to develop visceral metastasis.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias da Mama/patologia , Neoplasias Hepáticas/genética , Neoplasias Pulmonares/genética , Encéfalo/patologia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Regulação para Baixo , Feminino , Seguimentos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Pulmão/patologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Análise Serial de Tecidos/métodos , Transcriptoma/genética , Regulação para Cima
7.
J Dairy Sci ; 102(3): 2631-2644, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30692010

RESUMO

The aim of this study was to describe metabolism of early-lactation dairy cows by clustering cows based on glucose, insulin-like growth factor I (IGF-I), free fatty acid, and ß-hydroxybutyrate (BHB) using the k-means method. Predictive models for metabolic clusters were created and validated using 3 sets of milk biomarkers (milk metabolites and enzymes, glycans on the immunogamma globulin fraction of milk, and Fourier-transform mid-infrared spectra of milk). Metabolic clusters are used to identify dairy cows with a balanced or imbalanced metabolic profile. Around 14 and 35 d in milk, serum or plasma concentrations of BHB, free fatty acids, glucose, and IGF-I were determined. Cows with a favorable metabolic profile were grouped together in what was referred to as the "balanced" group (n = 43) and were compared with cows in what was referred to as the "other balanced" group (n = 64). Cows with an unfavorable metabolic profile were grouped in what was referred to as the "imbalanced" group (n = 19) and compared with cows in what was referred to as the "other imbalanced" group (n = 88). Glucose and IGF-I were higher in balanced compared with other balanced cows. Free fatty acids and BHB were lower in balanced compared with other balanced cows. Glucose and IGF-I were lower in imbalanced compared with other imbalanced cows. Free fatty acids and BHB were higher in imbalanced cows. Metabolic clusters were related to production parameters. There was a trend for a higher daily increase in fat- and protein-corrected milk yield in balanced cows, whereas that of imbalanced cows was higher. Dry matter intake and the daily increase in dry matter intake were higher in balanced cows and lower in imbalanced cows. Energy balance was continuously higher in balanced cows and lower in imbalanced cows. Weekly or twice-weekly milk samples were taken and milk metabolites and enzymes (milk glucose, glucose-6-phosphate, BHB, lactate dehydrogenase, N-acetyl-ß-d-glucosaminidase, isocitrate), immunogamma globulin glycans (19 peaks), and Fourier-transform mid-infrared spectra (1,060 wavelengths reduced to 15 principal components) were determined. Milk biomarkers with or without additional cow information (days in milk, parity, milk yield features) were used to create predictive models for the metabolic clusters. Accuracy for prediction of balanced (80%) and imbalanced (88%) cows was highest using milk metabolites and enzymes combined with days in milk and parity. The results and models of the present study are part of the GplusE project and identify novel milk-based phenotypes that may be used as predictors for metabolic and performance traits in early-lactation dairy cows.


Assuntos
Biomarcadores/análise , Bovinos/metabolismo , Lactação/fisiologia , Leite/química , Ácido 3-Hidroxibutírico/análise , Ácido 3-Hidroxibutírico/sangue , Animais , Biomarcadores/sangue , Glicemia/análise , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Feminino , Glucose/análise , Fator de Crescimento Insulin-Like I/análise , Gravidez , Espectroscopia de Infravermelho com Transformada de Fourier
8.
J Dairy Sci ; 101(12): 11413-11420, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316589

RESUMO

In the present study, we tested the hypothesis that overconditioning in dairy cows at the end of the dry period leads to infiltration of fat and alterations of the insulin secretory capacity of the pancreas. Pregnant Holstein Friesian dairy cows were selected based on body condition score (BCS) at the start of the dry period. Body condition score varied between cows to have optimal conditioned (2.5 < BCS ≤3.5, n = 5) and overconditioned (3.5 < BCS ≤5, n = 5) cows. All animals underwent an intravenous glucose tolerance test (IVGTT) at an average of 260 d of gestation to measure the pancreatic insulin secretory capacity and assess peripheral insulin sensitivity regarding glucose metabolism. Eight days after the IVGTT, animals were slaughtered. The pancreas was dissected and weighed and tissue samples were taken for histological analysis. Results revealed that overconditioning in dairy cows led to fat infiltration in the pancreas and an increase in size of pancreatic islets expressed relative to the total area of pancreatic tissue. In addition, results revealed a positive correlation between serum fatty acid concentration and peak insulin concentration and area and number of pancreatic islets expressed relative to the total area of pancreatic tissue. The IVGTT revealed that overconditioned animals have a higher insulin secretory capacity of the pancreas, as demonstrated by higher peak insulin concentration, higher acute insulin response to glucose, and higher area under the curve (AUC) for insulin compared with optimal conditioned cows. A higher AUC for glucose during the first 60 min following administration of the glucose bolus in overconditioned cows indicates an insulin-resistant state regarding glucose metabolism. Our results suggest that the pancreas of overconditioned dairy cows at the end of gestation compensates for the concomitantly elevated level of peripheral insulin resistance by greater secretion of insulin.


Assuntos
Bovinos/metabolismo , Gorduras/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Pâncreas/metabolismo , Animais , Ácidos Graxos/metabolismo , Feminino , Teste de Tolerância a Glucose , Resistência à Insulina , Lactação , Gravidez
9.
J Dairy Sci ; 101(7): 6542-6555, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29627241

RESUMO

The aim of this study was to determine the number of adipose tissue macrophages (ATM) and the mRNA expression of adipokines [adiponectin (ADIPOQ), leptin (LEP), interleukin 6 (IL6), tumor necrosis factor (TNF), and interleukin 10 (IL10)] in different adipose depots from cows with a variable body condition score (BCS) at the end of the dry period. We hypothesized that the number of ATM and the expression of these adipokines depend on adipocyte size and the anatomical location of the adipose depot. Subcutaneous, omental, mesenteric, perirenal, and intrapelvic adipose tissue samples were taken immediately after euthanasia of 10 Holstein Friesian dairy cows (upcoming parity 2 to 5, age 3.9 ± 1.4 yr; mean ± standard deviation) at the end of pregnancy (actual days of pregnancy at the moment of euthanasia: 269 ± 5 d). During the dry period, all animals received similar diets to meet but not exceed requirements. Five animals were considered to have a normal BCS (2.5-3.5) and 5 animals were considered to be over-conditioned (BCS = 3.75-5). Body weight of the animals at the moment of euthanasia was 717 ± 77 kg. Expression of the different genes was determined by reverse transcription quantitative real-time PCR. Adipocyte size was determined by measuring the area of 100 adipocytes on histological sections. Average adipocyte area was 10,475 ± 1,019, 8,500 ± 780, 10,383 ± 1,227, 11,466 ± 1,039, and 11,087 ± 1,632 µm2 for the subcutaneous, mesenteric, omental, intrapelvic, and perirenal adipose depot, respectively. Immunohistochemistry using anti-bovine CD172a antibodies was performed to determine the proportion of ATM (the number of CD172a-positive cells per 100 adipocytes, given as a percentage). Expression of LEP, IL6, and TNF was positively associated with adipocyte size, whereas no association could be detected between ADIPOQ and IL10 with the size of the adipocytes. The omental adipose depot was especially infiltrated with ATM (1.92 ± 0.55, 1.10 ± 0.33, and 8.28 ± 2.24% for the subcutaneous, mesenteric, and omental adipose depot, respectively). The proportion of ATM was positively associated with the size of the adipocytes in the omental and mesenteric adipose depot. Expression of ADIPOQ, LEP, IL6, TNF, and IL10 differed among depots, which suggests differences in inflammatory characteristics depending on the anatomical location of depots. In conclusion, the results of the present study confirm the adipose tissue as a potential source of inflammatory mediators and demonstrate ATM infiltration, especially in the omental adipose depot.


Assuntos
Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Macrófagos/metabolismo , Prenhez/metabolismo , Adipócitos , Animais , Bovinos , Feminino , Macrófagos/fisiologia , Gravidez , Gordura Subcutânea
10.
J Dairy Sci ; 100(5): 4078-4089, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28259405

RESUMO

Scientific journals and popular press magazines are littered with articles in which the authors use data from dairy herd management software. Almost none of such papers include data cleaning and data quality assessment in their study design despite this being a very critical step during data mining. This paper presents 2 novel data cleaning methods that permit identification of animals with good and bad data quality. The first method is a deterministic or rule-based data cleaning method. Reproduction and mutation or life-changing events such as birth and death were converted to a symbolic (alphabetical letter) representation and split into triplets (3-letter code). The triplets were manually labeled as physiologically correct, suspicious, or impossible. The deterministic data cleaning method was applied to assess the quality of data stored in dairy herd management from 26 farms enrolled in the herd health management program from the Faculty of Veterinary Medicine Ghent University, Belgium. In total, 150,443 triplets were created, 65.4% were labeled as correct, 17.4% as suspicious, and 17.2% as impossible. The second method, a probabilistic method, uses a machine learning algorithm (random forests) to predict the correctness of fertility and mutation events in an early stage of data cleaning. The prediction accuracy of the random forests algorithm was compared with a classical linear statistical method (penalized logistic regression), outperforming the latter substantially, with a superior receiver operating characteristic curve and a higher accuracy (89 vs. 72%). From those results, we conclude that the triplet method can be used to assess the quality of reproduction data stored in dairy herd management software and that a machine learning technique such as random forests is capable of predicting the correctness of fertility data.


Assuntos
Indústria de Laticínios , Fertilidade , Algoritmos , Animais , Reprodução , Software
11.
J Dairy Sci ; 100(3): 2381-2387, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28109592

RESUMO

The aim of the present study was to point at the limitations of glucose tolerance tests (GTT) to assess peripheral tissue insulin sensitivity in dairy heifers in different physiological states (pregnancy and lactation). Intravenous GTT were performed in 5 nonpregnant, nonlactating heifers, 5 heifers at the end of pregnancy (12-7 d before calving), and 5 lactating primiparous cows (11-14 d after calving). Glucose and insulin concentrations were determined and area under the curve (AUC) and clearance rate of glucose and insulin were calculated. Additionally, data were analyzed using the minimal model to derive the insulin sensitivity parameter (Si). Basal glucose and insulin concentrations were greater in the nonpregnant, nonlactating heifers. Clearance rate of glucose and Si were lowest, whereas the AUC for glucose was greatest in the nonpregnant, nonlactating heifers. Insulin concentrations during the GTT were greater for the nonpregnant, nonlactating heifers. Results from the GTT in pregnant heifers and lactating primiparous cows are biased by the fact that a large part of the glucose disappearance during an intravenous GTT occurs independently of insulin by the pregnant uterus or the lactating mammary gland. As such, greater AUC of glucose, lower clearance rate of glucose, or lower Si derived from GTT performed in nonpregnant, nonlactating dairy heifers in the present study might indicate decreased peripheral tissue insulin sensitivity of the glucose metabolism or decreased insulin-independent glucose disappearance. Based on the results from a GTT, it is impossible to discriminate between both metabolic pathways. It can be concluded that parameters derived from GTT are not suited to compare peripheral tissue insulin sensitivity of the glucose metabolism between dairy heifers in different physiological states due to the large variation in insulin secretion and the substantial difference in insulin-independent glucose disposal associated with these physiological states.


Assuntos
Teste de Tolerância a Glucose , Lactação , Animais , Glicemia , Bovinos , Feminino , Insulina , Resistência à Insulina , Gravidez
12.
J Dairy Sci ; 99(3): 2319-2328, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26723122

RESUMO

The aim of the present research was to describe characteristics of adipose tissue lipolysis in dairy cows with a variable body condition score (BCS). Ten clinically healthy Holstein Friesian cows were selected based on BCS and euthanized 10 to 13 d before the expected parturition date. Immediately after euthanasia, adipose tissue samples were collected from subcutaneous and omental fat depots. In both depots, we observed an increase in adipocyte size with increasing BCS. Using an in vitro explant culture of subcutaneous and omental adipose tissue, we aimed to determine the influence of adipocyte size and localization of adipose depot on the lipolytic activity in basal conditions and after addition of isoproterenol (nonselective ß-agonist) and insulin in different concentrations. Glycerol release in the medium was used as a measure for lipolytic activity. We observed that the basal lipolytic activity of subcutaneous and omental adipose tissue increased with adipocyte volume, meaning that larger fat cells have higher basal lipolytic activity independent of the location of the adipose depot. Dose-response curves were created between the concentration of isoproterenol or insulin and the amount of glycerol released. The shape of the dose-response curves is determined by the concentration of isoproterenol and insulin needed to elicit the half-maximal effect and the maximal amount of stimulated glycerol release or the maximal inhibitory effect of insulin. We observed that larger fat cells released more glycerol upon maximal stimulation with isoproterenol and this was more pronounced in subcutaneous adipose tissue. Additionally, larger fat cells had a higher sensitivity toward lipolytic signals. We observed a trend for larger adipocytes to be more resistant to the maximal antilipolytic effect of insulin. The insulin concentration needed to elicit the half-maximal inhibitory effect of insulin was within the physiological range of insulin and was not influenced by adipocyte size or adipose depot. We conclude that overconditioned cows have larger adipocytes and are predisposed to excessive mobilization of body fat due to a higher basal and stimulated lipolytic activity of large adipocytes while the antilipolytic effect of insulin is preserved.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Bovinos/metabolismo , Lipólise , Adipócitos/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Animais , Composição Corporal , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Resistência à Insulina , Isoproterenol/farmacologia , Lactação , Omento/metabolismo , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/metabolismo
13.
J Dairy Sci ; 98(7): 4580-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25958289

RESUMO

The objective of the present research was to determine the insulin response of the glucose and fatty acid metabolism in dry dairy cows with a variable body condition score (BCS). Ten pregnant Holstein Friesian dairy cows (upcoming parity 2 to 5) were selected based on BCS at the beginning of the study (2mo before expected parturition date). During the study, animals were monitored weekly for BCS and backfat thickness and in the last 2wk, blood samples were taken for determination of serum nonesterified fatty acid (NEFA) concentration. Animals underwent a hyperinsulinemic euglycemic clamp test in the third week before the expected parturition date. The hyperinsulinemic euglycemic clamp test consisted of 4 consecutive insulin infusions with increasing insulin doses: 0.1, 0.5, 2, and 5mIU/kg per minute. For each insulin infusion period, a steady state was defined as a period of 30min where no or minor changes of the glucose infusion were necessary to keep the blood glucose concentration constant and near basal levels. During the steady state, the glucose infusion rate [steady state glucose infusion rate (SSGIR) in µmol/kg per minute] and NEFA concentration [steady state NEFA concentration (SSNEFA) in mmol/L] were determined and reflect the insulin response of the glucose and fatty acid metabolism. Dose response curves were created based on the insulin concentrations during the steady state and the SSGIR or SSNEFA. The shape of the dose response curves is determined by the concentration of insulin needed to elicit the half maximal effect (EC50) and the maximal SSGIR or the minimal SSNEFA for the glucose or fatty acid metabolism, respectively. The maximal SSGIR was negatively associated with variables reflecting adiposity of the cows (BCS, backfat thickness, NEFA concentration during the dry period, and absolute weight of the different adipose depots determined after euthanasia and dissection of the different depots), whereas the EC50 of the glucose metabolism was positively associated with these variables. These results reflect a decreased insulin sensitivity and a decreased insulin responsiveness of the glucose metabolism in overconditioned dry dairy cows. The minimal SSNEFA and the EC50 of the fatty acid metabolism were not associated with variables reflecting adiposity of the cows, meaning that the insulin response of the fatty acid metabolism was not associated with the level of fat accumulation in dry dairy cows. Additionally, within individual cows, the EC50 of the glucose metabolism was higher than the EC50 of the fatty acid metabolism, meaning that the response of the fatty acid metabolism occurs at lower insulin concentrations compared with the response of the glucose metabolism. It can be concluded that a negative association exists between the level of fat accumulation in pregnant dairy cows at the end of the dry period and the insulin response of the glucose metabolism.


Assuntos
Glicemia/metabolismo , Insulina/sangue , Metabolismo dos Lipídeos , Tecido Adiposo/metabolismo , Animais , Bovinos , Relação Dose-Resposta a Droga , Eutanásia Animal , Ácidos Graxos não Esterificados/sangue , Feminino , Técnica Clamp de Glucose , Hiperinsulinismo/sangue , Gravidez
16.
Br J Cancer ; 107(8): 1409-17, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-23047593

RESUMO

BACKGROUND: Using mRNA expression-derived signatures as predictors of individual patient outcome has been a goal ever since the introduction of microarrays. Here, we addressed whether analyses of tumour mRNA at the exon level can improve on the predictive power and classification accuracy of gene-based expression profiles using neuroblastoma as a model. METHODS: In a patient cohort comprising 113 primary neuroblastoma specimens expression profiling using exon-level analyses was performed to define predictive signatures using various machine-learning techniques. Alternative transcript use was calculated from relative exon expression. Validation of alternative transcripts was achieved using qPCR- and cell-based approaches. RESULTS: Both predictors derived from the gene or the exon levels resulted in prediction accuracies >80% for both event-free and overall survival and proved as independent prognostic markers in multivariate analyses. Alternative transcript use was most prominently linked to the amplification status of the MYCN oncogene, expression of the TrkA/NTRK1 neurotrophin receptor and survival. CONCLUSION: As exon level-based prediction yields comparable, but not significantly better, prediction accuracy than gene expression-based predictors, gene-based assays seem to be sufficiently precise for predicting outcome of neuroblastoma patients. However, exon-level analyses provide added knowledge by identifying alternative transcript use, which should deepen the understanding of neuroblastoma biology.


Assuntos
Éxons/genética , Neuroblastoma/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Receptor trkA/genética , Linhagem Celular Tumoral , Pré-Escolar , Perfilação da Expressão Gênica , Humanos , Lactente , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/mortalidade , Prognóstico , RNA Mensageiro , Fatores de Risco , Análise de Sobrevida
17.
Br J Cancer ; 107(8): 1399-408, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22976800

RESUMO

BACKGROUND: Tumours are responsive to temozolomide (TMZ) if they are deficient in O(6)-methylguanine-DNA methyltransferase (MGMT), and mismatch repair (MMR) proficient. METHODS: The effect of TMZ on medulloblastoma (MB) cell killing was analysed with clonogenic survival assays. Expression of DNA repair genes and enzymes was investigated using microarrays, western blot, and immunohistochemistry. DNA sequencing and promoter methylation analysis were employed to investigate the cause of loss of the expression of MMR gene MLH1. RESULTS: Temozolomide exhibited potent cytotoxic activity in D425Med (MGMT deficient, MLH1 proficient; IC(50)=1.7 µM), moderate activity against D341Med (MGMT proficient, MLH1 deficient), and DAOY MB cells (MGMT proficient, MLH1 proficient). MGMT inhibitor O(6)-benzylguanine sensitised DAOY, but not D341Med cells to TMZ. Of 12 MB cell lines, D341Med, D283Med, and 1580WÜ cells exhibited MMR deficiency due to MLH1 promoter hypermethylation. DNA sequencing of these cells provided no evidence for somatic genetic alterations in MLH1. Expression analyses of MMR and MGMT in MB revealed that all patient specimens (n=74; expression array, n=61; immunostaining, n=13) are most likely MMR proficient, whereas some tumours had low MGMT expression levels (according to expression array) or were totally MGMT deficient (3 out of 13 according to immunohistochemistry). CONCLUSION: A subset of MB may respond to TMZ as some patient specimens are MGMT deficient, and tumours appear to be MMR proficient.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Cerebelares/genética , Reparo de Erro de Pareamento de DNA/genética , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Meduloblastoma/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Linhagem Celular Tumoral , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Criança , Pré-Escolar , Metilases de Modificação do DNA/biossíntese , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/biossíntese , Enzimas Reparadoras do DNA/genética , Dacarbazina/uso terapêutico , Feminino , Humanos , Masculino , Meduloblastoma/tratamento farmacológico , Meduloblastoma/metabolismo , Proteína 1 Homóloga a MutL , Proteínas Nucleares/biossíntese , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Temozolomida , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
18.
Basic Res Cardiol ; 107(2): 242, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22258067

RESUMO

Primary chronic kidney disease is associated with high cardiovascular risk. However, the exact mechanisms behind this cardiorenal interaction remain unclear. We investigated the interaction between heart and kidneys in novel animal model for cardiorenal interaction. Normal Wistar rats and Munich Wistar Fromter rats, spontaneously developing renal dysfunction, were subjected to experimental myocardial infarction to induce cardiac dysfunction (CD) and combined cardiorenal dysfunction (CRD), respectively (N = 5-10). Twelve weeks later, cardiac- and renal parameters were evaluated. Cardiac, but not renal dysfunction was exaggerated in CRD. Accelerated cardiac dysfunction in CRD was indicated by decreased cardiac output (CD 109 ± 10 vs. CRD 79 ± 8 ml/min), diastolic dysfunction (E/e') (CD 26 ± 2 vs. CRD 50 ± 5) and left ventricular overload (LVEDP CD 10.8 ± 2.8 vs. CRD 21.6 ± 1.7 mmHg). Congestion in CRD was confirmed by increased lung and atrial weights, as well as exaggerated right ventricular hypertrophy. Absence of accelerated renal dysfunction, measured by increased proteinuria, was supported by absence of additional focal glomerulosclerosis or further decline of renal blood flow in CRD. Only advanced peripheral endothelial dysfunction, as found in CRD, appeared to correlate with both renal and cardiac dysfunction parameters. Thus, proteinuric rats with myocardial infarction showed accelerated cardiac but not renal dysfunction. As parameters mimic the cardiorenal syndrome, these rats may provide a clinically relevant model to study increased cardiovascular risk due to renal dysfunction. Peripheral endothelial dysfunction was the only parameter that correlated with both renal and cardiac dysfunction, which may indicate a mediating role in cardiorenal interaction.


Assuntos
Endotélio Vascular/fisiopatologia , Cardiopatias/complicações , Cardiopatias/fisiopatologia , Falência Renal Crônica/complicações , Falência Renal Crônica/fisiopatologia , Animais , Aorta/patologia , Aorta/fisiopatologia , Endotélio Vascular/patologia , Cardiopatias/patologia , Hemodinâmica , Masculino , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco
19.
J Chem Ecol ; 38(10): 1298-305, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23053915

RESUMO

The native leafmining moth Tischeria ekebladella (Lepidoptera: Tischeriidae) feeds on oaks and recently has become a pest of silviculture and urban green areas in central Europe. The behavioral responses of male moths to hexane extracts of whole bodies of calling females or males were tested under laboratory conditions. Only extracts of females elicited responses from males. Analysis of extracts by coupled gas chromatography/electroantennographic detection revealed the presence of two electroantennogram-active peaks. Structure elucidation of these compounds, by gas-chromatography/mass spectrometry and independent synthesis revealed them to be (3Z,6Z,9Z)-tricosa-3,6,9-triene and (3Z,6Z,9Z,19Z)-tricosa-3,6,9,19-tetraene. While the triene was present in both sexes, the tetraene was female-specific. The latter is a new structure for a pheromone component of Lepidoptera and a novel natural product. Field trapping tests, carried out in a mixed oak forest near Budapest (Hungary), using synthetic compounds applied to rubber dispensers, showed that the tetraene per se elicited catches of males in large numbers. When the triene was added to the tetraene in a ratio of 1:1, there was no increase in trap catch; the triene alone did not elicit catches of males. For monitoring this insect, the tetraene, applied to rubber dispensers at a dose of 300 µg, is a potent sex attractant.


Assuntos
Mariposas/química , Mariposas/fisiologia , Atrativos Sexuais/isolamento & purificação , Atrativos Sexuais/metabolismo , Animais , Antenas de Artrópodes/efeitos dos fármacos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hungria , Masculino , Mariposas/efeitos dos fármacos , Atrativos Sexuais/síntese química , Comportamento Sexual Animal/efeitos dos fármacos
20.
Cell Metab ; 3(1): 5-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16399499

RESUMO

Nicotinamide nucleotide transhydrogenase (Nnt) detoxifies reactive oxygen species (ROS), byproducts of mitochondrial metabolism that, when accumulated, can decrease mitochondrial ATP production. In this issue of Cell Metabolism, demonstrate that Nnt in pancreatic beta cells is important for insulin release. Their compelling data highlight the critical roles for ATP generation and subsequent closure of KATP channels for insulin secretion.


Assuntos
Insulina/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/fisiologia , NADP Trans-Hidrogenases/fisiologia , Animais , Secreção de Insulina , Células Secretoras de Insulina/enzimologia , Células Secretoras de Insulina/metabolismo , Camundongos , Proteínas Mitocondriais/genética , NADP Trans-Hidrogenases/genética
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