1,608 research outputs found

    Levels of milk glycosaminoglycans in Holstein cows with clinical and subclinical mastitis

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    Mastitis is an inflammation of the mammary gland whose diagnosis is based on clinical criteria and the determination of inflammatory markers. The disease is mainly caused by bacteria causing intra-mammary infections. The etiological agent/s are detected by milk culture or by molecular biology approaches. However, these methodologies are unpractical for on-farm diagnosis, where rapid decisions must be made when infected animals are detected. For this reason, the levels of glycosaminoglycans (GAGs) in milk were evaluated as a tool for the diagnosis of mastitis. GAGs levels were determined by the dimethylmethylene blue assay (DMMB) method in milk from healthy animals and in milk from animals with mastitis caused by different etiological agents. Low levels of GAGs (1.93 ± 0.40 mg) were found in milk samples obtained from healthy animals (H), while intermediate (2.4 ± 0.61 mg) and high levels (2.87 ± 0.7 mg) were found in milk obtained from cows with subclinical (SM) and clinical mastitis (CM), respectively. Statistically significant differences were found between the SM and H groups (p < 0.001) and between CM and the other groups (p < 0.0001). The highest levels of GAGs were detected in the CM group, in which coagulase negative Staphylococcus (CNS) and Streptococcus spp. were isolated. Animals infected by S. aureus had the highest levels of GAGs in the SM group. The sensitivity (Se) and specificity (Sp) for the assessment of GAGs levels for CM diagnosis were 89.7 % and 81.6 %, respectively. For the diagnosis of SM, Se and Sp were 73.2 % and 95 %, respectively. The area under the curve for the diagnosis of CM was 0.902 (p < 0.0001), while that for SM was 0.833 (p < 0.0001). Results suggest that the measurement of GAGs levels in milk can be used as an indicator of udder health in dairy cattle, since increased levels of GAGs were associated with mastitis.Fil: Caggiano, Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Fisiología Animal; ArgentinaFil: Crespi, Elisa Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fiorini, Gonzalo. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Fisiología Animal; ArgentinaFil: de Simone, Emilio Adrian. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Fisiología Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Discrete Changes in Glucose Metabolism Define Aging

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    Aging is a physiological process in which multifactorial processes determine a progressive decline. Several alterations contribute to the aging process, including telomere shortening, oxidative stress, deregulated autophagy and epigenetic modifications. In some cases, these alterations are so linked with the aging process that it is possible predict the age of a person on the basis of the modification of one specific pathway, as proposed by Horwath and his aging clock based on DNA methylation. Because the energy metabolism changes are involved in the aging process, in this work, we propose a new aging clock based on the modifications of glucose catabolism. The biochemical analyses were performed on mononuclear cells isolated from peripheral blood, obtained from a healthy population with an age between 5 and 106 years. In particular, we have evaluated the oxidative phosphorylation function and efficiency, the ATP/AMP ratio, the lactate dehydrogenase activity and the malondialdehyde content. Further, based on these biochemical markers, we developed a machine learning-based mathematical model able to predict the age of an individual with a mean absolute error of approximately 9.7 years. This mathematical model represents a new non-invasive tool to evaluate and define the age of individuals and could be used to evaluate the effects of drugs or other treatments on the early aging or the rejuvenation

    Microbiota modulation counteracts Alzheimer's disease progression influencing neuronal proteolysis and gut hormones plasma levels

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    Gut microbiota has a proven role in regulating multiple neuro-chemical pathways through the highly interconnected gut-brain axis. Oral bacteriotherapy thus has potential in the treatment of central nervous system-related pathologies, such as Alzheimer's disease (AD). Current AD treatments aim to prevent onset, delay progression and ameliorate symptoms. In this work, 3xTg-AD mice in the early stage of AD were treated with SLAB51 probiotic formulation, thereby affecting the composition of gut microbiota and its metabolites. This influenced plasma concentration of inflammatory cytokines and key metabolic hormones considered therapeutic targets in neurodegeneration. Treated mice showed partial restoration of two impaired neuronal proteolytic pathways (the ubiquitin proteasome system and autophagy). Their cognitive decline was decreased compared with controls, due to a reduction in brain damage and reduced accumulation of amyloid beta aggregates. Collectively, our results clearly prove that modulation of the microbiota induces positive effects on neuronal pathways that are able to slow down the progression of Alzheimer's disease

    Functional Magnetic Resonance Imaging of Rats with Experimental Autoimmune Encephalomyelitis Reveals Brain Cortex Remodeling.

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    UNLABELLED: Cortical reorganization occurring in multiple sclerosis (MS) patients is thought to play a key role in limiting the effect of structural tissue damage. Conversely, its exhaustion may contribute to the irreversible disability that accumulates with disease progression. Several aspects of MS-related cortical reorganization, including the overall functional effect and likely modulation by therapies, still remain to be elucidated. The aim of this work was to assess the extent of functional cortical reorganization and its brain structural/pathological correlates in Dark Agouti rats with experimental autoimmune encephalomyelitis (EAE), a widely accepted preclinical model of chronic MS. Morphological and functional MRI (fMRI) were performed before disease induction and during the relapsing and chronic phases of EAE. During somatosensory stimulation of the right forepaw, fMRI demonstrated that cortical reorganization occurs in both relapsing and chronic phases of EAE with increased activated volume and decreased laterality index versus baseline values. Voxel-based morphometry demonstrated gray matter (GM) atrophy in the cerebral cortex, and both GM and white matter atrophy were assessed by ex vivo pathology of the sensorimotor cortex and corpus callosum. Neuroinflammation persisted in the relapsing and chronic phases, with dendritic spine density in the layer IV sensory neurons inversely correlating with the number of cluster of differentiation 45-positive inflammatory lesions. Our work provides an innovative experimental platform that may be pivotal for the comprehension of key mechanisms responsible for the accumulation of irreversible brain damage and for the development of innovative therapies to reduce disability in EAE/MS. SIGNIFICANCE STATEMENT: Since the early 2000s, functional MRI (fMRI) has demonstrated profound modifications in the recruitment of cortical areas during motor, cognitive, and sensory tasks in multiple sclerosis (MS) patients. Experimental autoimmune encephalomyelitis (EAE) represents a reliable model of the chronic-progressive variant of MS. fMRI studies in EAE have not been performed extensively up to now. This paper reports fMRI studies in a rat model of MS with somatosensory stimulation of the forepaw. We demonstrated modifications in the recruitment of cortical areas consistent with data from MS patients. To the best of our knowledge, this is the first report of cortical remodeling in a preclinical in vivo model of MS.This work was supported by grants from the National Multiple Sclerosis Society (NMSS; RG-4001-A1 to SP), the Italian Multiple Sclerosis Foundation (FISM; RG 2010/R/31 to SP and FISM Grant 10/12/F14/2011 to PM), the Italian Ministry of Health (GR08/7 to SP), the European Research Council (ERC) 2010-SIG (RG 260511-SEM_SEM to SP), the European Community (EC) 7th Framework Programme (FP7/2007-2013; RG 280772-iONE to SP), The Evelyn Trust (RG 69865 to SP), The Bascule Charitable Trust (RG 75149 to SP). LPJ is supported by a Wellcome Trust Research Training Fellowship (RRZA/057).This is the final version of the article. It first appeared from Society for Neuroscience via http://dx.doi.org/10.1523/JNEUROSCI.0540-15.201

    High diagnostic accuracy of RT-QuIC assay in a prospective study of patients with suspected sCJD

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    The early and accurate in vivo diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) is essential in order to differentiate CJD from treatable rapidly progressive dementias. Diagnostic investigations supportive of clinical CJD diagnosis include magnetic resonance imaging (MRI), electroencephalogram (EEG), 14-3-3 protein detection, and/or real-time quaking-induced conversion (RT-QuIC) assay positivity in the cerebrospinal fluid (CSF) or in other tissues. The total CSF tau protein concentration has also been used in a clinical setting for improving the CJD diagnostic sensitivity and specificity. We analyzed 182 CSF samples and 42 olfactory mucosa (OM) brushings from patients suspected of having sCJD with rapidly progressive dementia (RPD), in order to determine the diagnostic accuracy of 14-3-3, the total tau protein, and the RT-QuIC assay. A probable and definite sCJD diagnosis was assessed in 102 patients. The RT-QuIC assay on the CSF samples showed a 100% specificity and a 96% sensitivity, significantly higher compared with 14-3-3 (84% sensitivity and 46% specificity) and tau (85% sensitivity and 70% specificity); however, the combination of RT-QuIC testing of the CSF and OM samples resulted in 100% sensitivity and specificity, proving a significantly higher accuracy of RT-QuIC compared with the surrogate biomarkers in the diagnostic setting of patients with RPD. Moreover, we showed that CSF blood contamination or high protein levels might interfere with RT-QuIC seeding. In conclusion, we provided further evidence that the inclusion of an RT-QuIC assay of the CSF and OM in the diagnostic criteria for sCJD has radically changed the clinical approach towards the diagnosis

    Evaluation of brain activity changes occurring in an animal model for multiple sclerosis: a functional Magnetic Resonance Imaging study

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    Multiple Sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). Magnetic Resonance Imaging (MRI), showing the extent of the involvement of CNS, plays a major role in the assessment of patients with MS. Further information can be obtained with functional MRI (fMRI) which may be used in MS patients to investigate the functional reorganization of cortical areas. fMRI observations in MS are already available in humans, but deeper knowledge on its usefulness might be gained using reliable animal models. We investigated by means of fMRI the brain plasticity in a chronic model of MS, i.e. Experimental Autoimmune Encephalomyelitis (EAE) in the Dark Agouti (DA) rat strain. Serial fMRI acquisitions were performed before, 30 and 60 days after EAE induction. fMRI with somatosensory stimulation was performed according to ref [1]. Briefly electrical stimulation (a train of squared pulses with frequency=3Hz, current=2mA, duration=0.5ms) was delivered to the left forepaw during acquisition of MR images sensitive to Blood-Volume. A single stimulation protocol was composed of 30 images under rest condition and 10 images acquired during stimulation. After appropriate image analysis, performed using the FSL software package [2], the brain region activated by the applied stimulus was determined. Prior to EAE induction, electrical stimulation resulted in a localized response in the contralateral sensory motor cortex according to previously reported results [1]. Thirty and 60 days after EAE Induction, the activated area was greatly increased covering large regions of both contra and ipsilateral somatosensory cortex and extending also to extra-cortical regions. Our results show that the experimental model of EAE in DA rats reproduces a remarkable findings observed in MS patients, i.e. the functional reorganization of motor cortex. It remains to be investigated whether this effect could represent an innovative platform for testing new therapeutic approaches for MS

    Azathioprine in refractory sprue: results from a prospective, open-label study

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    OBJECTIVE: Refractory sprue is a rare and severe malabsorptive disorder that mimics celiac disease but is refractory to a gluten-free diet and is without initial evidence of overt lymphoma. Treatment is largely empiric and often ineffective, with steroids and immunosuppression being the mainstream therapeutic options. The aim of this study was to evaluate prospectively the effect of azathioprine on a group of patients diagnosed with refractory sprue. METHODS: We studied seven consecutive patients (five women and two men) with a well-defined diagnosis of refractory sprue and a lack of response to oral or parenteral steroids. At diagnosis, five patients had endoscopic evidence of ulcerative jejunitis, and five underwent exploratory laparotomy for exclusion of malignancies. The characteristic monoclonal TCR gene rearrangement was shown in five of six patients studied. Patients were treated for a mean of 11 months (range 8–12 months), and clinical, biochemical, molecular, and histological parameters were reassessed at the end of the trial. The study was a prospective, open-label, non–placebo-controlled study using azathioprine (2 mg/kg/ day) plus oral prednisone (1 mg/kg/day). A gluten-free diet (n 7) as well as enteral (n 6) and parenteral nutrition (n 5) were administered during the trial. RESULTS: After treatment, five patients had a complete clinical remission, and biochemical and nutritional parameters were significantly improved. Steroids were tapered after the onset of azathioprine, and no patient was on steroids at the end of the trial. Intestinal histology improved significantly in all cases (normal histology in three cases and minor infiltration in the lamina propria in two). Two patients did not respond to treatment at any time and died in months 10 and 9, of an irreversible ventricular fibrillation and sepsis, respectively. No overt lymphoma was demonstrated during the follow-up. CONCLUSIONS: The present study confirms earlier anecdotal reports on the efficacy of azathioprine in refractory sprue, with clear clinical and histological improvement shown in most patients. However, monoclonality persisted after treatment. We consider that a larger number of patients should be evaluated before a definitive recommendation is adopted for use of this drug in refractory sprue.Fil: Maurino, Eduardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; Argentina. Universidad del Salvador; ArgentinaFil: Niveloni, Sonia Isabel. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Cherñavsky, Alejandra Claudia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Inmunogenética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Pedreira, Silvia. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Mazure, Roberto. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Vazquez, Daniel Horacio. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Reyes, Hugo. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Fiorini, Alcira. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Smecuol, Edgardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Cabanne, Ana. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Capucchio, Monica. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Inmunogenética; ArgentinaFil: Kogan, Zulema. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; ArgentinaFil: Bai, Julio C.. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; Argentina. Universidad del Salvador; Argentin

    Pancreatic cancer growth using magnetic resonance and bioluminescence imaging

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    OBJECT:Pancreatic cancer is one of the most lethal human cancer and appropriate experimental tumor models are needed for the development of innovative therapeutic approaches. This paper describes an experimental model of human pancreatic cancer and a related non invasive imaging technique suitable for monitoring tumor growth and metastatization. The aim of the work was the implementation of an experimental platform suitable for assessing the efficacy of new therapeutic agents.MATERIALS AND METHODS:Human pancreatic cancer cells (PANC-1-Luc+) were injected into the pancreas of female athymic CD1 mice. Magnetic Resonance Imaging (MRI) at 4.7T and Bioluminescence Imaging (BLI) were performed in each mouse at three time points after cell inoculation (1, 2 and 3months). Two groups of mice were studied: the first group of n=13 mice in which 5*106 cells were injected and the second group of n=10 mice in which 2*106 cells were injected. MRI examination included T2w acquisitions and (at the last time point) Dynamic-contrast-enhanced-MRI (DCE-MRI).RESULTS:Each mouse underwent three longitudinal MRI and BLI examinations. BLI was more sensitive than MRI producing higher detection rate at early time points. Moreover in one case of abdominal dissemination of pancreatic tumor cells, small tumoral masses were detected by BLI and not detected by MRI. However BLI appears more prone to experimental error most likely due to photon attenuation. In 4 mice BLI produced false negative results. DCE-MRI experiments providing information on tumor perfusion were conducted successfully in this anatomical district and demonstrated that the tumor tissues from the second experimental group are more vascularized compared to the first group.CONCLUSION:The present study performed on the experimental model of pancreatic cancer here described shows that MRI and BLI are complementary techniques and that synergistic application of both can overcome the intrinsic limitations of each.Object Pancreatic cancer is one of the most lethal human cancer and appropriate experimental tumor models are needed for the development of innovative therapeutic approaches. This paper describes an experimental model of human pancreatic cancer and a related non invasive imaging technique suitable for monitoring tumor growth and metastatization. The aim of the work was the implementation of an experimental platform suitable for assessing the efficacy of new therapeutic agents.Materials and methods: Human pancreatic cancer cells (PANC-1-Luc +) were injected into the pancreas of female athymic CD1 mice. Magnetic Resonance Imaging (MRI) at 4.7 T and Bioluminescence Imaging (BLI) were performed in each mouse at three time points after cell inoculation (1, 2 and 3 months). Two groups of mice were studied: the first group of n = 13 mice in which 5 * 10(6) cells were injected and the second group of n = 10 mice in which 2 * 10(6) cells were injected. MRI examination included T2w acquisitions and (at the last time point) Dynamic-contrast-enhanced-MRI (DCE-MRI).Results: Each mouse underwent three longitudinal MRI and BLI examinations. BLI was more sensitive than MRI producing higher detection rate at early time points. Moreover in one case of abdominal dissemination of pancreatic tumor cells, small tumoral masses were detected by BLI and not detected by MRI. However BLI appears more prone to experimental error most likely due to photon attenuation. In 4 mice BLI produced false negative results. DCE-MRI experiments providing information on tumor perfusion were conducted successfully in this anatomical district and demonstrated that the tumor tissues from the second experimental group are more vascularized compared to the first group.Conclusion: The present study performed on the experimental model of pancreatic cancer here described shows that MRI and BLI are complementary techniques and that synergistic application of both can overcome the intrinsic limitations of each. (C) 2015 Elsevier Inc. All rights reserved

    Cerebrospinal Fluid Markers in Sporadic Creutzfeldt-Jakob Disease

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    Sporadic Creutzfeldt-Jakob disease (sCJD) is the commonest form of human prion diseases, accounting for about 85% of all cases. Current criteria for intra vitam diagnosis include a distinct phenotype, periodic sharp and slow-wave complexes at electroencephalography (EEG), and a positive 14-3-3-protein assay in the cerebrospinal fluid (CSF). In sCJD, the disease phenotype may vary, depending upon the genotype at codon 129 of the prion protein gene (PRNP), a site of a common methionine/valine polymorphism, and two distinct conformers of the pathological prion protein. Based on the combination of these molecular determinants, six different sCJD subtypes are recognized, each with distinctive clinical and pathologic phenotypes. We analyzed CSF samples from 127 subjects with definite sCJD to assess the diagnostic value of 14-3-3 protein, total tau protein, phosphorylated181 tau, and amyloid beta (Aβ) peptide 1-42, either alone or in combination. While the 14-3-3 assay and tau protein levels were the most sensitive indicators of sCJD, the highest sensitivity, specificity and positive predictive value were obtained when all the above markers were combined. The latter approach also allowed a reliable differential diagnosis with other neurodegenerative dementias

    Polymer-coated superparamagnetic iron oxide nanoparticles as T2 contrast agent for MRI and their uptake in liver

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    Aim: To study the efficiency of multifunctional polymer-based superparamagnetic iron oxide nanoparticles (bioferrofluids) as a T2 magnetic resonance contrast agent and their uptake and toxicity in liver. Materials & methods: Mice were intravenously injected with bioferrofluids and Endorem\uae. The magnetic resonance efficiency, uptake and in vivo toxicity were investigated by means of magnetic resonance imaging (MRI) and histological techniques. Results: Bioferrofluids are a good T2 contrast agent with a higher r2/r1 ratio than Endorem. Bioferrofluids have a shorter blood circulation time and persist in liver for longer time period compared with Endorem. Both bioferrofluids and Endorem do not generate any noticeable histological lesions in liver over a period of 60 days post-injection. Conclusion: Our bioferrofluids are powerful diagnostic tool without any observed toxicity over a period of 60 days post-injection
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