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1.
BMC Vet Res ; 15(1): 442, 2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31805933

RESUMEN

BACKGROUND: In the past years, it became apparent that health status and performance differ considerably within dairy farms in Northern Germany. In order to obtain clues with respect to possible causes of these differences, a case-control study was performed. Case farms, which showed signs of health and performance problems, and control farms, which had none of these signs, were compared. Risk factors from different areas such as health management, housing, hygiene and nutrition were investigated as these are known to be highly influential. The aim of this study was to identify major factors within these areas that have the strongest association with health and performance problems of dairy herds in Northern Germany. RESULTS: In the final model, a lower energy density in the roughage fraction of the diet, more pens with dirty lying areas and a low ratio of cows per watering spaces were associated with a higher risk for herd health problems. Moreover, case farms were affected by infections with intestinal parasites, lungworms, liver flukes and Johne's Disease numerically more often than control farms. Case farms more often had pens with raised cubicles compared to the deep bedded stalls or straw yards found in control farms. In general, the hygiene of the floors and beddings was worse in case farms. Concerning nutrition, the microbiological and sensory quality of the provided silages was often insufficient, even in control farms. Less roughage was provided to early lactating cows and the feed was pushed to the feeding fence less frequently in case farms than in control farms. CONCLUSIONS: The results show that milk yield and health status were associated with various factors from different areas stressing the importance of all aspects of management for good animal health and performance. Moreover, this study confirmed well-known risk factors for health problems and performance losses. These should better be taken heed of in herd health management.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Lactancia , Crianza de Animales Domésticos , Bienestar del Animal , Animales , Estudios de Casos y Controles , Bovinos , Femenino , Alemania/epidemiología , Factores de Riesgo
2.
Pflugers Arch ; 466(11): 2127-38, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24531759

RESUMEN

Metabolic acidosis is a common feature of tumor microenvironment and may affect the phenotype of tumor cells, including invasive capacity and formation of metastases. We tested whether previous exposure to an acidic environment alters metastatic potential of two rat carcinoma cell lines in the animal model. In addition, we determined the effect of an acidic environment on motility and invasive capacity of AT-1 prostate carcinoma cells in culture. Exposure of tumor cells to an acidic environment (pH 6.6, 5 % CO2, 6 h) prior to tail vein injection in rats enhanced formation of lung metastases significantly. In culture, acidosis increased cellular motility of AT-1 cells. When the tumor cells were transferred back to pH 7.4, enhanced motility persisted for at least 3 h but vanished after longer periods (24 h), therefore presenting a "short-term memory effect." Although acidosis augmented phosphorylation of ERK1/2 and p38, and inhibition of ERK1/2 phosphorylation or of p38 kinase activity reduced basal motility at pH 7.4, acidosis-induced increase in motility was not dependent on ERK1/2 or p38 kinase. Src family kinases were not involved either. By contrast, scavenging reactive oxygen species (ROS), known to be increased in AT-1 cells under acidic conditions, blunted acidosis-induced motility increase. Our data indicate that tumor cells may acquire enhanced motility in an acidic micromilieu, at least in part due to enhanced ROS formation. Because enhanced motility persists for at least 3 h after leaving the acidic environment, this may promote metastasis formation, as observed in our in vivo model.


Asunto(s)
Acidosis/patología , Metástasis de la Neoplasia/patología , Acidosis/metabolismo , Animales , Línea Celular Tumoral , Concentración de Iones de Hidrógeno , Sistema de Señalización de MAP Quinasas/fisiología , Fosforilación/fisiología , Ratas , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Familia-src Quinasas/metabolismo
3.
Animals (Basel) ; 14(15)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39123700

RESUMEN

The decision to euthanize a compromised pig can be challenging for pig farmers and veterinarians. To understand more about the challenges in Germany, a cross-sectional online survey was conducted. Based on a hybrid design, the responses of 39 veterinarians and 62 pig farmers were analyzed to generate a list of common clinical signs associated with the euthanasia of sows, fatteners, and piglets. Moreover, a set of influences on the farm, due to economic and personal considerations, were found to shape the decision-making process. The two most salient reasons outlined for the delay of timely euthanasia were uncertainty and misinterpretation of the chance for healing. The lack of valid clinical signs or a sound justification was most frequently mentioned as a challenge to the general decision-making process. In summation, this study highlights the need to generate a valid taxonomy for clinical signs that includes their development in a compromised pig over time. Future studies should elaborate on the justification of euthanasia decisions to facilitate the resolution of ethical dilemmas among the involved pig farmers and veterinarians. Lastly, the results suggest that clinical reasoning and consultation skills should be included when decision-making behavior is to be trained.

4.
Adv Exp Med Biol ; 789: 221-228, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23852498

RESUMEN

Cells in solid tumors generate an extracellular acidosis due to the Warburg effect and tissue hypoxia. Acidosis can affect the functional behavior of tumor cells, causing, e.g., multidrug resistance. In this process ERK1/2 and p38 mitogen-activated protein kinases (MAPK) seem to play a key role. However, the underlying mechanism of MAPK activation by extracellular acidosis remains unclear. Experiments were performed in three tumor and three normal tissue cell lines in which the cells were exposed to an extracellular pH of 6.6 for 3 h. Intracellular pH (pHi), protein expression and activation, acidosis-induced transactivation, and reactive oxygen species (ROS) formation were measured. Extracellular acidosis resulted in a rapid and sustained decrease of pHi leading to a reversal of the extra-/intracellular pH gradient. Extracellular acidosis led to p38 phosphorylation in all cell types and to ERK1/2 phosphorylation in three of six cell lines. Furthermore, p38 phosphorylation was also observed during sole intracellular lactacidosis at normal pHe. Acidosis-enhanced formation of ROS, probably originating from mitochondria, seems to trigger MAPK phosphorylation. Finally, acidosis increased phosphorylation of the transcription factor CREB and resulted in increased transcriptional activity. Thus, an acidic tumor microenvironment can induce a longer-lasting p38 CREB-mediated change in the transcriptional program.


Asunto(s)
Acidosis/metabolismo , Neoplasias/metabolismo , Transducción de Señal/fisiología , Microambiente Tumoral/fisiología , Animales , Células CHO , Línea Celular , Línea Celular Tumoral , Cricetulus , Perros , Humanos , Concentración de Iones de Hidrógeno , Sistema de Señalización de MAP Quinasas , Células de Riñón Canino Madin Darby , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
5.
Front Oncol ; 13: 1222573, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37538111

RESUMEN

Fatigue is a very common side effect during intravenous chemotherapy. Unfortunately, only few effective therapeutic options are available, mostly based on daily activity. In our pilot trial we were able to demonstrate that intermittent fasting can reduce fatigue in healthy people, thus we aimed to assess the effects of the fasting dietary on quality of life during chemotherapy in patients with gynecological cancer, especially on the domain of fatigue. The IFAST trial is designed as a prospective, randomized-controlled, multi-center trial. Participation will be offered to women with gynecological cancers (breast cancer, ovarian cancer including peritoneal and fallopian tube cancers, endometrial cancer and cervical cancer) who are planned to receive intravenous chemotherapy for at least three months. Eligible patients will be randomized 1:1, stratified by tumor type and study center. Primary endpoint is the difference in mean change in fatigue, assessed with the Functional Assessment of Chronic Illness Therapy-Fatigue Scale (FACIT- FS©). Exploratory secondary endpoints will include general Quality of Life impairment, tolerance of chemotherapy, immunological changes, peripheral cell damage in blood cells, as well as tumor response to chemotherapy. There is new evidence that prolonged fasting periods of 46-96 hours during chemotherapy can positively influence the quality of life during chemotherapy. However, these fasting regiments are not feasible for many patients. Intermittent fasting could be a feasible (manageable) option for many patients to actively improve their quality of life and tolerance to chemotherapy and possibly even enhance the effectiveness of chemotherapy. Trial Registration: https://drks.de, identifier DRKS00031429.

6.
Arterioscler Thromb Vasc Biol ; 31(7): 1643-52, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21512163

RESUMEN

OBJECTIVE: Pathophysiological effects of the epidermal growth factor receptor (EGFR or ErbB1) include vascular remodeling. EGFR transactivation is proposed to contribute significantly to heterologous signaling and remodeling in vascular smooth muscle cells (VSMC). METHODS AND RESULTS: We investigated the importance of EGFR in primary VSMC from aorta of mice with targeted deletion of the EGFR (EGFR(Δ/Δ VSMC)→VSMC(EGFR-/-) and EGFR(Δ/+ VSMC)→VSMC(EGFR+/-)) and the respective littermate controls (EGFR(+/+ VSMC)→VSMC(EGFR+/+)) with respect to survival, pentose phosphate pathway activity, matrix homeostasis, extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, and Ca(2+) homeostasis. In VSMC(EGFR-/-), epidermal growth factor-induced signaling was abolished; VSMC(EGFR+/-) showed an intermediate phenotype. EGFR deletion enhanced spontaneous cell death, reduced pentose phosphate pathway activity, disturbed cellular matrix homeostasis (collagen III and fibronectin), and abolished epidermal growth factor sensitivity. In VSMC(EGFR-/-) endothelin-1- or α(1)-adrenoceptor-induced ERK1/2 phosphorylation and the fraction of Ca(2+) responders were significantly reduced, whereas responsive cells showed a significantly stronger Ca(2+) signal. Oxidative stress (H(2)O(2)) induced ERK1/2 activation in VSMC(EGFR+/+) and VSMC(EGFR+/-) but not in VSMC(EGFR-/-). The Ca(2+) signal was enhanced in VSMC(EGFR-/-), similar to purinergic stimulation by ATP. CONCLUSIONS: In conclusion, EGFR was found to be important for basal VSMC homeostasis and ERK1/2 activation by the tested G-protein-coupled receptors or radical stress. Ca(2+) signaling was modulated by EGFR differentially with respect to the fraction of responders and magnitude of the signal. Thus, EGFR seems to be Janus-faced for VSMC biology.


Asunto(s)
Receptores ErbB/deficiencia , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Transducción de Señal , Adenosina Trifosfato/metabolismo , Agonistas de Receptores Adrenérgicos alfa 1/farmacología , Animales , Señalización del Calcio , Supervivencia Celular , Células Cultivadas , Endotelina-1/metabolismo , Receptores ErbB/efectos de los fármacos , Receptores ErbB/genética , Matriz Extracelular/metabolismo , Genotipo , Homeostasis , Peróxido de Hidrógeno/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Oxidantes/farmacología , Estrés Oxidativo , Vía de Pentosa Fosfato , Fenotipo , Fenilefrina/farmacología , Fosforilación , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factores de Tiempo
7.
Nat Commun ; 13(1): 6936, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36376288

RESUMEN

Human infections with H7N9 avian influenza A virus that emerged in East China in 2013 and caused high morbidity rates were more frequently detected in men than in women over the last five epidemic waves. However, molecular markers associated with poor disease outcomes in men are still unknown. In this study, we systematically analysed sex hormone and cytokine levels in males and females with laboratory-confirmed H7N9 influenza in comparison to H7N9-negative control groups as well as laboratory-confirmed seasonal H1N1/H3N2 influenza cases (n = 369). Multivariable analyses reveal that H7N9-infected men present with considerably reduced testosterone levels associated with a poor outcome compared to non-infected controls. Regression analyses reveal that testosterone levels in H7N9-infected men are negatively associated with the levels of several pro-inflammatory cytokines, such as IL-6 and IL-15. To assess whether there is a causal relationship between low testosterone levels and avian H7N9 influenza infection, we used a mouse model. In male mice, we show that respiratory H7N9 infection leads to a high viral load and inflammatory cytokine response in the testes as well as a reduction in pre-infection plasma testosterone levels. Collectively, these findings suggest that monitoring sex hormone levels may support individualized management for patients with avian influenza infections.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Subtipo H7N9 del Virus de la Influenza A , Gripe Aviar , Gripe Humana , Humanos , Masculino , Femenino , Animales , Ratones , Subtipo H3N2 del Virus de la Influenza A , Testosterona , Citocinas , China/epidemiología
8.
Digit Biomark ; 5(2): 148-157, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34414352

RESUMEN

BACKGROUND: The life science industry has a strong interest in real-world data (RWD), a term that is currently being used in many ways and with varying definitions depending on the source. In this review article, we provide a summary overview of the challenges and risks regarding the use of RWD and its translation into real-world evidence and provide a classification and visualization of RWD challenges by means of the RWD Challenges Radar. SUMMARY: Based on a systematic literature search, we identified 3 types of challenges - organizational, technological, and people-based - that must be addressed when deriving evidence from RWD to be used in drug approval and other applications. It further demonstrates that numerous different aspects, for example, related to the application field and the associated industry, must be considered. A key finding in our review is that the regulatory landscape must be carefully assessed before utilizing RWD. KEY MESSAGES: Establishing awareness and insight into the challenges and risks regarding the use of RWD will be key to taking full advantage of the RWD potential. As a result of this review, an "RWD Challenges Radar" will support the establishment of awareness by providing a comprehensive overview of the relevant aspects to be considered when employing RWD.

9.
Animals (Basel) ; 11(7)2021 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-34359205

RESUMEN

Pasture-borne parasites adversely affect bovine health and productivity worldwide. In Europe, gastrointestinal nematodes, especially Ostertagia ostertagi, the liver fluke Fasciola hepatica and the lungworm Dictyocaulus viviparus represent the most important parasites of dairy cattle. The present study assessed exposure towards these parasites among 646 cattle herds in three parts of Germany during 2017-2019 via antibody detection in bulk tank milk (BTM). Overall, O. ostertagi levels indicative of production losses were detected in 41.2% (266/646; 95% confidence interval (CI): 37.4-45.1%) of BTM samples, while F. hepatica seroprevalence amounted to 14.9% (96/646; 95% CI: 12.2-17.9%). Only 2.3% (15/646; 95% CI: 1.4-3.9%) of samples were D. viviparus antibody-positive. Significantly lower O. ostertagi as well as F. hepatica seroprevalence was detected in dual-purpose breeds compared to high-performance breeds from the same region. Management factors related to parasite exposure included access to fresh grass and hay, silage quality and anthelmintic treatment. Furthermore, F. hepatica and O. ostertagi seropositivity was significantly associated with suboptimal herd-level body condition. Interestingly, the relationship between seropositivity and productivity differed between breed types. Negative impacts on milk yield were detected only in high-performance breeds, while O. ostertagi seropositivity was associated with a lower milk fat content in dual-purpose herds.

10.
Emerg Microbes Infect ; 10(1): 1807-1818, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34402750

RESUMEN

Male sex was repeatedly identified as a risk factor for death and intensive care admission. However, it is yet unclear whether sex hormones are associated with disease severity in COVID-19 patients. In this study, we analysed sex hormone levels (estradiol and testosterone) of male and female COVID-19 patients (n = 50) admitted to an intensive care unit (ICU) in comparison to control non-COVID-19 patients at the ICU (n = 42), non-COVID-19 patients with the most prevalent comorbidity (coronary heart diseases) present within the COVID-19 cohort (n = 39) and healthy individuals (n = 50). We detected significantly elevated estradiol levels in critically ill male COVID-19 patients compared to all control cohorts. Testosterone levels were significantly reduced in critically ill male COVID-19 patients compared to control cohorts. No statistically significant differences in sex hormone levels were detected in critically ill female COVID-19 patients, albeit similar trends towards elevated estradiol levels were observed. Linear regression analysis revealed that among a broad range of cytokines and chemokines analysed, IFN-γ levels are positively associated with estradiol levels in male and female COVID-19 patients. Furthermore, male COVID-19 patients with elevated estradiol levels were more likely to receive ECMO treatment. Thus, we herein identified that disturbance of sex hormone metabolism might present a hallmark in critically ill male COVID-19 patients.


Asunto(s)
COVID-19/mortalidad , COVID-19/patología , Estradiol/sangre , Testosterona/sangre , Anciano , Anciano de 80 o más Años , COVID-19/sangre , Cuidados Críticos , Enfermedad Crítica , Oxigenación por Membrana Extracorpórea , Femenino , Humanos , Hipogonadismo/patología , Unidades de Cuidados Intensivos , Interferón gamma/sangre , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Distribución por Sexo
11.
Int J Cancer ; 123(11): 2532-42, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18729196

RESUMEN

Because solid growing tumors often show hypoxia and pronounced extracellular acidosis, the aim of this study was to analyze the impact of an acidotic environment on the activity of the p-glycoprotein (pGP) and on the cellular content and cytotoxicity of the chemotherapeutic drug daunorubicin in the AT1 R-3327 Dunning prostate carcinoma cell line cultured in vitro and in vivo. In vitro, extracellular acidosis (pH 6.6) activated p38 and ERK1/2 and thereby induced daunorubicin resistance via a pronounced activation of pGP. De-novo protein synthesis was not necessary and analysis of transport kinetics indicated a fast and persistent pGP activation at pH 6.6 (when compared with 7.4). Intracellular acidification also induced daunorubicin resistance via activation of pGP, which was mediated by activation of p38 alone. In vivo, tumors were implanted subcutaneously, and the tumor pH was artificially lowered by forcing anaerobic metabolism. In vivo, the reduced extracellular pH of 6.6 was also able to induce daunorubicin resistance, which was abolished by inhibition of p38. These results suggest that pGP activity is dependent on extracellular pH in vitro and in vivo. Moreover, there is strong indication that this effect is mediated via activation of p38 in vivo. Activation of ERK is also suitable to induce pGP activity. Therefore, inhibition of p38 (and ERK) may be used to prevent acidosis induced increase in pGP activity and thereby attenuate multidrug resistance. In addition, supportive treatments reducing tumor acidosis may improve the cytotoxic effect of chemotherapeutic drugs.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Acidosis/metabolismo , Acidosis/patología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Caspasa 3/metabolismo , Proliferación Celular/efectos de los fármacos , Daunorrubicina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Concentración de Iones de Hidrógeno , Masculino , Trasplante de Neoplasias , Proteína Quinasa C/metabolismo , Ratas
12.
Prev Vet Med ; 142: 39-45, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28606364

RESUMEN

Resistance to third-generation cephalosporins and other beta-lactam antibiotics is of major concern for animal and human health. Knowledge of the prevalence of resistant bacteria in primary production is an important element to estimate transmission along the stages in the food production chain and the exposure of the human population. The primary objective of this study was to determine the prevalence of cefotaxime-resistant commensal E. coli in dairy and beef cattle production units throughout Germany. Secondarily, the association between management factors and the presence of cefotaxime resistance was investigated. In total, 60 beef cattle and 52 dairy cattle production units all over Germany were included. Cefotaxime-resistant E. coli were isolated from at least one sample in 70% (95% CI: 58-83%) of the farms keeping beef cattle and 85% (95% CI: 75-94%) of the farms keeping dairy cattle. The sample prevalence was 35% (161/455; 95% CI: 31-40%) and 48% (156/323; 95% CI: 43-54%), respectively. Most factors associated with resistance to cefotaxime indicate that less intensive production results in a lower number of positive samples. For beef cattle, antimicrobial treatment of the whole animal group was significantly associated with an increased proportion of samples containing cefotaxime resistant E. coli. In addition, our results indicate that better hygiene management could improve the resistance situation on cattle farms.


Asunto(s)
Antibacterianos/farmacología , Enfermedades de los Bovinos/tratamiento farmacológico , Cefotaxima/farmacología , Infecciones por Escherichia coli/veterinaria , Escherichia coli/efectos de los fármacos , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Estudios Transversales , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli/tratamiento farmacológico , Granjas , Alemania , Prevalencia
13.
Prev Vet Med ; 125: 154-7, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26783199

RESUMEN

In this investigation the farm prevalence of cefotaxime-resistant Escherichia coli (CREC) in German broiler farms was evaluated. In total, 59 flocks on 34 broiler farms were sampled in four agricultural regions of Germany. Per broiler flock, three faecal samples, a pair of boot swabs and one dust sample were taken and examined for the presence of CREC. After pre-enrichment of sample material in Luria-Bertani-broth, the broth was streaked onto MacConkey agar containing 1mg/l cefotaxime (CTX). CREC isolates were detected in at least one sample from each flock resulting in a farm prevalence of 100%. The proportion of positive samples was high in all three sample types. Of 177 collective faecal samples 81.9% were positive, of 59 boot swabs and 59 dust samples 79.7% and 62.7% were positive. In conclusion, the prevalence of broiler farms with cefotaxime-resistant E. coli in Germany is very high. We suggest that the analysis of collective faecal samples is sufficient to determine the CREC farm status. In addition to other studies our study supports the finding that cefotaxime resistance is a good proxy for the presence of ESBL- or plasmidic AmpC-beta-lactamases.


Asunto(s)
Antibacterianos/farmacología , Cefotaxima/farmacología , Pollos , Infecciones por Escherichia coli/veterinaria , Escherichia coli/efectos de los fármacos , Enfermedades de las Aves de Corral/epidemiología , Resistencia betalactámica , Animales , Estudios Transversales , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Alemania/epidemiología , Enfermedades de las Aves de Corral/microbiología , Prevalencia
14.
Sci Rep ; 4: 7430, 2014 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-25503263

RESUMEN

Non-physiological activation of the mineralocorticoid receptor (MR), e.g. by aldosterone under conditions of high salt intake, contributes to the pathogenesis of cardiovascular diseases, although beneficial effects of aldosterone also have been described. The epidermal growth factor receptor (EGFR) contributes to cardiovascular alterations and mediates part of the MR effects. Recently, we showed that EGFR is required for physiological homeostasis and function of heart and arteries in adult animals. We hypothesize that moderate high aldosterone/NaCl, at normal blood pressure, affects the cardiovascular system depending on cardiovascular EGFR. Therefore we performed an experimental series in male and female animals each, using a recently established mouse model with EGFR knockout in vascular smooth muscle cells and cardiomyocytes and determined the effects of a mild-high aldosterone-to-NaCl constellation on a.o. marker gene expression, heart size, systolic blood pressure, impulse conduction and heart rate. Our data show that (i) cardiac tissue of male but not of female mice is sensitive to mild aldosterone/NaCl treatment, (ii) EGFR knockout induces stronger cardiac disturbances in male as compared to female animals and (iii) mild aldosterone/NaCl treatment requires the EGFR in order to disturb cardiac tissue homeostasis whereas beneficial effects of aldosterone seem to be independent of EGFR.


Asunto(s)
Aldosterona/fisiología , Receptores ErbB/fisiología , Miocardio/metabolismo , Cloruro de Sodio/metabolismo , Aldosterona/farmacología , Animales , Biomarcadores/metabolismo , Femenino , Homeostasis , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Cloruro de Sodio/farmacología , Transcriptoma
15.
Prev Vet Med ; 116(1-2): 129-37, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25042772

RESUMEN

A cross-sectional study concerning farm prevalence and risk factors for the count of cefotaxime resistant Escherichia coli (E. coli) (CREC) positive samples per sampling group on German fattening pig farms was performed in 2011 and 2012. Altogether 48 farms in four agricultural regions in the whole of Germany were investigated. Faecal samples, boot swabs and dust samples from two sampling groups per farm were taken and supplemental data were collected using a questionnaire. On 85% of the farms, at least one sample contained cefotaxime resistant E. coli colonies. Positive samples were more frequent in faeces (61%) and boot swabs (54%) than in dust samples (11%). Relevant variables from the questionnaire were analysed in a univariable mixed effect Poisson regression model. Variables that were related to the number (risk) of positive samples per sampling group with a p-value <0.2 were entered in a multivariable model. This model was reduced to statistically significant variables via backward selection. Factors that increased the risk for positive samples involved farm management and hygienic aspects. Farms that had a separate pen for diseased pigs had a 2.8 higher mean count of positive samples (95%-CI [1.71; 4.58], p=0.001) than farms without an extra pen. The mean count was increased on farms with under-floor exhaust ventilation compared to farms with over floor ventilation (2.22 [1.43; 3.46], p=0.001) and more positive samples were observed on farms that controlled flies with toxin compared to farms that did not (1.86 [1.24; 2.78], p=0.003). It can be concluded, that CREC are wide spread on German fattening pig farms. In addition the explorative approach of the present study suggests an influence of management strategies on the occurrence of cefotaxime resistant E. coli.


Asunto(s)
Antibacterianos/farmacología , Cefotaxima/farmacología , Infecciones por Escherichia coli/veterinaria , Escherichia coli/efectos de los fármacos , Enfermedades de los Porcinos/epidemiología , Resistencia betalactámica , Animales , Recuento de Colonia Microbiana/veterinaria , Estudios Transversales , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Alemania/epidemiología , Prevalencia , Factores de Riesgo , Porcinos , Enfermedades de los Porcinos/microbiología
16.
Hypertension ; 61(2): 333-40, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23248150

RESUMEN

The epidermal growth factor receptor (EGFR), a receptor tyrosine kinase, contributes to parainflammatory dysregulation, possibly causing cardiovascular dysfunction and remodeling. The physiological role of cardiovascular EGFR is not completely understood. To investigate the physiological importance of EGFR in vascular smooth muscle cells and cardiomyocytes, we generated a mouse model with targeted deletion of the EGFR using the SM22 (smooth muscle-specific protein 22) promoter. While the reproduction of knockout animals was not impaired, life span was significantly reduced. Systolic blood pressure was not different between the 2 genotypes-neither in tail cuff nor in intravascular measurements-whereas total peripheral vascular resistance, diastolic blood pressure, and mean blood pressure were reduced. Loss of vascular smooth muscle cell-EGFR results in a dilated vascular phenotype with minor signs of fibrosis and inflammation. Echocardiography, necropsy, and histology revealed a dramatic eccentric cardiac hypertrophy in knockout mice (2.5-fold increase in heart weight), with increased stroke volume and cardiac output as well as left ventricular wall thickness and lumen. Cardiac hypertrophy is accompanied by an increase in cardiomyocyte volume, a strong tendency to cardiac fibrosis and inflammation, as well as enhanced NADPH-oxidase 4 and hypertrophy marker expression. Thus, in cardiomyocytes, EGFR prevents excessive hypertrophic growth through its impact on reactive oxygen species balance, whereas in vascular smooth muscle cells EGFR contributes to the appropriate vascular wall architecture and vessel reactivity, thereby supporting a physiological vascular tone.


Asunto(s)
Cardiomegalia/metabolismo , Receptores ErbB/metabolismo , Hipotensión/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos del Músculo Liso/metabolismo , Animales , Presión Sanguínea/fisiología , Gasto Cardíaco/fisiología , Cardiomegalia/genética , Cardiomegalia/fisiopatología , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Receptores ErbB/genética , Hipotensión/genética , Hipotensión/fisiopatología , Ratones , Ratones Noqueados , Músculo Liso Vascular/fisiopatología , Especies Reactivas de Oxígeno/metabolismo
17.
PLoS One ; 6(7): e22445, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21818325

RESUMEN

Tumor micromilieu often shows pronounced acidosis forcing cells to adapt their phenotype towards enhanced tumorigenesis induced by altered cellular signalling and transcriptional regulation. In the presents study mechanisms and potential consequences of the crosstalk between extra- and intracellular pH (pH(e), pH(i)) and mitogen-activated-protein-kinases (ERK1/2, p38) was analyzed. Data were obtained mainly in AT1 R-3327 prostate carcinoma cells, but the principle importance was confirmed in 5 other cell types. Extracellular acidosis leads to a rapid and sustained decrease of pH(i) in parallel to p38 phosphorylation in all cell types and to ERK1/2 phosphorylation in 3 of 6 cell types. Furthermore, p38 phosphorylation was elicited by sole intracellular lactacidosis at normal pH(e). Inhibition of ERK1/2 phosphorylation during acidosis led to necrotic cell death. No evidence for the involvement of the kinases c-SRC, PKC, PKA, PI3K or EGFR nor changes in cell volume in acidosis-induced MAPK activation was obtained. However, our data reveal that acidosis enhances the formation of reactive oxygen species (ROS), probably originating from mitochondria, which subsequently trigger MAPK phosphorylation. Scavenging of ROS prevented acidosis-induced MAPK phosphorylation whereas addition of H(2)O(2) enhanced it. Finally, acidosis increased phosphorylation of the transcription factor CREB via p38, leading to increased transcriptional activity of a CRE-reporter even 24 h after switching the cells back to a normal environmental milieu. Thus, an acidic tumor microenvironment can induce a longer lasting p38-CREB-medited change in the transcriptional program, which may maintain the altered phenotype even when the cells leave the tumor environment.


Asunto(s)
Ácidos/metabolismo , Sistema de Señalización de MAP Quinasas , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neoplasias/enzimología , Neoplasias/patología , Especies Reactivas de Oxígeno/metabolismo , Microambiente Tumoral , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Perros , Activación Enzimática/efectos de los fármacos , Espacio Extracelular/efectos de los fármacos , Espacio Extracelular/metabolismo , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Modelos Biológicos , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/metabolismo , Ratas , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Microambiente Tumoral/efectos de los fármacos
18.
Hypertens Res ; 34(5): 623-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21346767

RESUMEN

We examined the contribution of transforming growth factor (TGF)-ß-T-cell signaling to aldosterone (aldo)/salt-induced fibrosis in the kidneys and the hearts of FVB/N wild-type (WT) or transgenic (Tg) mice expressing a dominant-negative TGF-ß type II receptor in T cells (hCD2-ΔkTßRII). Animals received aldo through osmotic minipumps and had access to either 1% NaCl (aldo/NaCl group) or tap water (vehicle group) for 4 weeks. Systolic blood pressure was measured during this period via a tail cuff. The animals were then killed, and urine, blood, kidneys and hearts were collected. Systolic blood pressure did not differ between the groups. Aldo/NaCl enhanced renal, cardiac and left ventricular weight in WT animals slightly, but only renal weight was increased in Tg animals. Urinary protein excretion was enhanced in Tg animals (fourfold) and increased further in WT (twofold) and Tg (1.8-fold) mice on aldo/NaCl treatment. Aldo/NaCl increased interstitial fibrosis in the kidneys (1.5-fold) and the hearts of WT (2.5-fold) animals. Under control conditions, Tg mouse cardiac (3.2-fold) and renal (1.7-fold) tissues were slightly more fibrotic compared with WT, and this condition was not further aggravated by aldo/NaCl. Aldo/NaCl-induced mRNA expression of renal fibronectin (10.7-fold in WT) but not of renal collagen mRNA expression (WT: Col1a1 7.7-fold; Col3a1, 3.1-fold; and Col4a1 3.3-fold) was abrogated in Tg animals. In hearts, aldo/NaCl-induced plasminogen activator inhibitor-1 mRNA (twofold) expression depended on TGF-ß-T-cell signaling. Our results indicate that (i) aldo/NaCl can induce renal and cardiac damage in the absence of blood pressure changes, (ii) the elimination TGF-ß-T-cell cross-talk leads to renal and cardiac fibrosis but does not exacerbate aldo/NaCl-induced damage and (iii) the pathological aldo/NaCl effect is modified, in part, by TGF-ß-T-cell cross-talk.


Asunto(s)
Aldosterona/farmacología , Riñón/patología , Miocardio/patología , Cloruro de Sodio Dietético/farmacología , Linfocitos T/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Colágeno/biosíntesis , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Fibronectinas/biosíntesis , Fibrosis , Riñón/efectos de los fármacos , Ratones , Ratones Transgénicos , Tamaño de los Órganos/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/biosíntesis , Proteinuria/inducido químicamente , Linfocitos T/patología , Factor de Crecimiento Transformador beta/genética
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