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1.
Phys Rev Lett ; 128(15): 151801, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499871

RESUMO

We report a measurement of the energy-dependent total charged-current cross section σ(E_{ν}) for inclusive muon neutrinos scattering on argon, as well as measurements of flux-averaged differential cross sections as a function of muon energy and hadronic energy transfer (ν). Data corresponding to 5.3×10^{19} protons on target of exposure were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab booster neutrino beam with a mean neutrino energy of approximately 0.8 GeV. The mapping between the true neutrino energy E_{ν} and reconstructed neutrino energy E_{ν}^{rec} and between the energy transfer ν and reconstructed hadronic energy E_{had}^{rec} are validated by comparing the data and Monte Carlo (MC) predictions. In particular, the modeling of the missing hadronic energy and its associated uncertainties are verified by a new method that compares the E_{had}^{rec} distributions between data and a MC prediction after constraining the reconstructed muon kinematic distributions, energy, and polar angle to those of data. The success of this validation gives confidence that the missing energy in the MicroBooNE detector is well modeled and underpins first-time measurements of both the total cross section σ(E_{ν}) and the differential cross section dσ/dν on argon.

2.
Phys Rev Lett ; 128(24): 241801, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35776450

RESUMO

We present a measurement of ν_{e} interactions from the Fermilab Booster Neutrino Beam using the MicroBooNE liquid argon time projection chamber to address the nature of the excess of low energy interactions observed by the MiniBooNE Collaboration. Three independent ν_{e} searches are performed across multiple single electron final states, including an exclusive search for two-body scattering events with a single proton, a semi-inclusive search for pionless events, and a fully inclusive search for events containing all hadronic final states. With differing signal topologies, statistics, backgrounds, reconstruction algorithms, and analysis approaches, the results are found to be either consistent with or modestly lower than the nominal ν_{e} rate expectations from the Booster Neutrino Beam and no excess of ν_{e} events is observed.

3.
Phys Rev Lett ; 128(11): 111801, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363017

RESUMO

We report results from a search for neutrino-induced neutral current (NC) resonant Δ(1232) baryon production followed by Δ radiative decay, with a ⟨0.8⟩ GeV neutrino beam. Data corresponding to MicroBooNE's first three years of operations (6.80×10^{20} protons on target) are used to select single-photon events with one or zero protons and without charged leptons in the final state (1γ1p and 1γ0p, respectively). The background is constrained via an in situ high-purity measurement of NC π^{0} events, made possible via dedicated 2γ1p and 2γ0p selections. A total of 16 and 153 events are observed for the 1γ1p and 1γ0p selections, respectively, compared to a constrained background prediction of 20.5±3.65(syst) and 145.1±13.8(syst) events. The data lead to a bound on an anomalous enhancement of the normalization of NC Δ radiative decay of less than 2.3 times the predicted nominal rate for this process at the 90% confidence level (C.L.). The measurement disfavors a candidate photon interpretation of the MiniBooNE low-energy excess as a factor of 3.18 times the nominal NC Δ radiative decay rate at the 94.8% C.L., in favor of the nominal prediction, and represents a greater than 50-fold improvement over the world's best limit on single-photon production in NC interactions in the sub-GeV neutrino energy range.

4.
Phys Rev Lett ; 127(15): 151803, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678031

RESUMO

We present a search for the decays of a neutral scalar boson produced by kaons decaying at rest, in the context of the Higgs portal model, using the MicroBooNE detector. We analyze data triggered in time with the Fermilab NuMI neutrino beam spill, with an exposure of 1.93×10^{20} protons on target. We look for monoenergetic scalars that come from the direction of the NuMI hadron absorber, at a distance of 100 m from the detector, and decay to electron-positron pairs. We observe one candidate event, with a standard model background prediction of 1.9±0.8. We set an upper limit on the scalar-Higgs mixing angle of θ<(3.3-4.6)×10^{-4} at the 95% confidence level for scalar boson masses in the range (100-200) MeV/c^{2}. We exclude, at the 95% confidence level, the remaining model parameters required to explain the central value of a possible excess of K_{L}^{0}→π^{0}νν[over ¯] decays reported by the KOTO collaboration. We also provide a model-independent limit on a new boson X produced in K→πX decays and decaying to e^{+}e^{-}.

5.
Phys Rev Lett ; 125(20): 201803, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33258649

RESUMO

We report on the first measurement of flux-integrated single differential cross sections for charged-current (CC) muon neutrino (ν_{µ}) scattering on argon with a muon and a proton in the final state, ^{40}Ar (ν_{µ},µp)X. The measurement was carried out using the Booster Neutrino Beam at Fermi National Accelerator Laboratory and the MicroBooNE liquid argon time projection chamber detector with an exposure of 4.59×10^{19} protons on target. Events are selected to enhance the contribution of CC quasielastic (CCQE) interactions. The data are reported in terms of a total cross section as well as single differential cross sections in final state muon and proton kinematics. We measure the integrated per-nucleus CCQE-like cross section (i.e., for interactions leading to a muon, one proton, and no pions above detection threshold) of (4.93±0.76_{stat}±1.29_{sys})×10^{-38} cm^{2}, in good agreement with theoretical calculations. The single differential cross sections are also in overall good agreement with theoretical predictions, except at very forward muon scattering angles that correspond to low-momentum-transfer events.

6.
J Transl Med ; 14: 3, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26733412

RESUMO

Consistent evidence associates IGF-1 deficiency and metabolic syndrome. In this review, we will focus on the metabolic effects of IGF-1, the concept of metabolic syndrome and its clinical manifestations (impaired lipid profile, insulin resistance, increased glucose levels, obesity, and cardiovascular disease), discussing whether IGF-1 replacement therapy could be a beneficial strategy for these patients. The search plan was made in Medline for Pubmed with the following mesh terms: IGF-1 and "metabolism, carbohydrate, lipids, proteins, amino acids, metabolic syndrome, cardiovascular disease, diabetes" between the years 1963-2015. The search includes animal and human protocols. In this review we discuss the relevant actions of IGF-1 on metabolism and the implication of IGF-1 deficiency in the establishment of metabolic syndrome. Multiple studies (in vitro and in vivo) demonstrate the association between IGF-1 deficit and deregulated lipid metabolism, cardiovascular disease, diabetes, and an altered metabolic profile of diabetic patients. Based on the available data we propose IGF-1 as a key hormone in the pathophysiology of metabolic syndrome; due to its implications in the metabolism of carbohydrates and lipids. Previous data demonstrates how IGF-1 can be an effective option in the treatment of this worldwide increasing condition. It has to distinguished that the replacement therapy should be only undertaken to restore the physiological levels, never to exceed physiological ranges.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Síndrome Metabólica/metabolismo , Animais , Metabolismo dos Carboidratos , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos , Modelos Biológicos
7.
J Transl Med ; 13: 326, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26467524

RESUMO

BACKGROUND: Insulin growth factor 1 (IGF-1) has multiple effects on metabolism. Much evidence suggests that the deficiency of this hormone increases insulin resistance, impairs lipid metabolism, augments oxidative damage and deregulates the neuro-hormonal axis. An inverse relationship between IGF-1 levels and the prevalence of Metabolic Syndrome (MetS) with its cardiovascular complications has been identified. However, the underlying mechanisms linking IGF-1 and MetS are still poorly understood. In order to elucidate such mechanisms, the aim of this work was to study, in mice with partial IGF-1 deficiency, liver expression of genes involved in glucose and lipid metabolism as well as serum levels of glucose, triglycerides and cholesterol, as well as liver malondialdehyde (MDA) levels, as a marker for oxidative damage. METHODS: Three experimental groups were studied in parallel: Controls (CO), wild type mice (igf-1 (+/+)); untreated heterozygous mice (Hz, igf-1 (+/-)) and Hz (igf-1 (+/-)) mice treated with low doses of IGF-1 for 10 days (Hz + IGF-1). RESULTS: A reduction of IGF-1 serum levels in the Hz group was found, which was normalized by IGF-1 therapy. Serum levels of glucose, triglycerides and cholesterol were significantly increased in the untreated Hz group as compared to both controls and Hz + IGF-1 groups. The expression of genes involved in gluconeogenesis, glycogenolysis, lipid synthesis and transport, and catabolism were altered in untreated Hz animals and the expression of most of them was normalized by IGF-1 therapy; MDA was also significantly increased in the Hz untreated group. CONCLUSIONS: The mere partial IGF-1 deficiency is responsible for the reduction in the expression of genes involved in glucose and lipid metabolism, resulting in dyslipidemia and hyperglycemia. Such genetic alterations may seriously contribute to the establishment of MetS.


Assuntos
Metabolismo dos Carboidratos/genética , Modelos Animais de Doenças , Glucose/metabolismo , Fator de Crescimento Insulin-Like I/genética , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Síndrome Metabólica/genética , Animais , Peso Corporal , Ácidos Graxos/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Camundongos , Camundongos Knockout , Tamanho do Órgão , Triglicerídeos/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-29147569

RESUMO

Herein, we present a 14-year-old patient with short stature (134 cm) referred from Paediatrics to our department for complementary evaluation since growth hormone (GH) treatment failed to show any improvement. He was born premature and small for gestational age. Genital examination classified the patient as Tanner I-II with small penis and testicular size for his age. Biochemical analyses revealed normal GH levels with low serum insulin-like growth factor-1 (IGF-1). Molecular diagnosis confirmed several mutations in IGF1R and IGFALS, and so he was diagnosed with Laron Syndrome or GH insensibility and treated with IGF-1 substitutive therapy. LEARNING POINTS: Evaluation of the GH/IGF-1 axis when short stature does not respond to conservative treatment must be included in the ordinary practice.Laron Syndrome real incidence should be calculated once undiagnosed cases arise, as treatment, due to lack of market, is unaffordable.Even when adulthood is reached, and no longitudinal growth can be achieved, still IGF-1 treatment in Laron Syndrome patients should be pursued as metabolic and protective derangements could arise.

9.
J Physiol Biochem ; 73(2): 245-258, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28124277

RESUMO

Even though the liver synthesizes most of circulating IGF-1, it lacks its receptor under physiological conditions. However, according to previous studies, a damaged liver expresses the receptor. For this reason, herein, we examine hepatic histology and expression of genes encoding proteins of the cytoskeleton, extracellular matrix, and cell-cell molecules and inflammation-related proteins. A partial IGF-1 deficiency murine model was used to investigate IGF-1's effects on liver by comparing wild-type controls, heterozygous igf1+/-, and heterozygous mice treated with IGF-1 for 10 days. Histology, microarray for mRNA gene expression, RT-qPCR, and lipid peroxidation were assessed. Microarray analyses revealed significant underexpression of igf1 in heterozygous mice compared to control mice, restoring normal liver expression after treatment, which then normalized its circulating levels. IGF-1 receptor mRNA was overexpressed in Hz mice liver, while treated mice displayed a similar expression to that of the controls. Heterozygous mice showed overexpression of several genes encoding proteins related to inflammatory and acute-phase proteins and underexpression or overexpression of genes which coded for extracellular matrix, cytoskeleton, and cell junction components. Histology revealed an altered hepatic architecture. In addition, liver oxidative damage was found increased in the heterozygous group. The mere IGF-1 partial deficiency is associated with relevant alterations of the hepatic architecture and expression of genes involved in cytoskeleton, hepatocyte polarity, cell junctions, and extracellular matrix proteins. Moreover, it induces hepatic expression of the IGF-1 receptor and elevated acute-phase and inflammation mediators, which all resulted in liver oxidative damage.


Assuntos
Proteínas de Fase Aguda/metabolismo , Regulação da Expressão Gênica , Hepatite/metabolismo , Mediadores da Inflamação/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/metabolismo , Receptores de Somatomedina/metabolismo , Proteínas de Fase Aguda/genética , Animais , Caderinas/genética , Caderinas/metabolismo , Cruzamentos Genéticos , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Desmossomos/imunologia , Desmossomos/metabolismo , Desmossomos/patologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Hepatite/imunologia , Hepatite/patologia , Hepatite/prevenção & controle , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/administração & dosagem , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/uso terapêutico , Peroxidação de Lipídeos , Fígado/imunologia , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Estresse Oxidativo , Receptores de Somatomedina/genética , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo
10.
Urology ; 86(6): 1241.e1-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26408501

RESUMO

OBJECTIVE: To determine whether insulin-like growth factor (IGF-1) deficiency can cause testicular damage and to examine changes of the testicular morphology and testicular function-related gene expression caused by IGF-1 deficiency. Therefore, this study aims to determine the benefits of low doses of IGF-1 and to explore the mechanisms underlying the IGF-1 replacement therapy. MATERIALS AND METHODS: A murine model of IGF-1 deficiency was used to avoid any factor that could contribute to testicular damage. Testicular weight, score of histopathological damage, and gene expressions were studied in 3 experimental groups of mice: controls (wild-type Igf1(+/+)), heterozygous Igf1(+/-) with partial IGF-1 deficiency, and heterozygous Igf1(+/-) treated with IGF-1. RESULTS: Results show that the partial IGF-1 deficiency induced testicular damage and altered expression of genes involved in IGF-1 and growth hormone signaling and regulation, testicular hormonal function, extracellular matrix establishment and its regulation, angiogenesis, fibrogenesis, inflammation, and cytoprotection. In addition, proteins involved in tight junction expression were found to be reduced. However, low doses of IGF-1 restored the testicular damage and most of these parameters. CONCLUSION: IGF-1 deficiency caused the damage of the blood-testis barrier and testicular structure and induced the abnormal testicular function-related gene expressions. However, low doses of IGF-1 constitute an effective replacement therapy that restores the described testicular damage. Data herein show that (1) cytoprotective activities of IGF-1 seem to be mediated by heat shock proteins and that (2) connective tissue growth factor could play a relevant role together with IGF-1 in the extracellular matrix establishment.


Assuntos
Barreira Hematotesticular/química , Proteínas da Matriz Extracelular/genética , Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/deficiência , Fator de Crescimento Insulin-Like I/farmacologia , Proteoglicanas/genética , Testículo/patologia , Testículo/fisiopatologia , Proteínas ADAM/genética , Animais , Antígenos CD18/genética , Caderinas/análise , Fator de Crescimento do Tecido Conjuntivo/genética , Citocromo P-450 CYP3A/genética , Modelos Animais de Doenças , Fertilinas , Expressão Gênica/genética , Genótipo , Inibinas/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Masculino , Glicoproteínas de Membrana/genética , Metaloproteases/genética , Camundongos , Tamanho do Órgão , Receptor IGF Tipo 1/genética , Receptores do FSH/análise , Receptores da Somatotropina/análise , Receptores da Somatotropina/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Testículo/química , Junções Íntimas/química , Inibidor Tecidual de Metaloproteinase-1/genética , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador beta/genética , Fator A de Crescimento do Endotélio Vascular/genética , Proteína da Zônula de Oclusão-1/análise , beta Catenina/análise
12.
Mol Genet Metab ; 72(3): 199-208, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11243725

RESUMO

Enzyme replacement therapy (ERT) has long been considered an approach to treating lysosomal storage disorders caused by deficiency of lysosomal enzymes. ERT is currently used to treat Gaucher disease and is being developed for several lysosomal storage disorders now that recombinant sources of the enzymes have become available. We have continued development of ERT for mucopolysaccharidosis I (MPS I) using the feline model. Recombinant alpha-L-iduronidase was administered intravenously at low dose (approximately 0.1 mg/kg or 25,000 units/kg) to four cats and high dose (0.5 mg/kg or 125,000 units/kg) to two cats on a weekly basis for 3- or 6-month terms. Clinical examinations showed distinct clearing of corneal clouding in one cat although clinical effects in the others were not evident. Biochemical studies of the cats showed that the enzyme was distributed to a variety of tissues although the liver and spleen contained the highest enzyme activities. Glycosaminoglycan storage was decreased in liver and spleen, and the histologic appearance improved in liver, spleen, and renal cortex. Enzyme was not consistently detected in cerebral cortex, brainstem, or cerebellum and the histologic appearance and ganglioside profiles did not improve. A variety of other tissues showed low variable uptake of enzyme and no distinct improvement. IgG antibodies to alpha-L-iduronidase were observed in five cats with higher titers noted when higher doses were administered. Mild complement activation occurred in three cats. Enzyme replacement therapy was effective in reversing storage in some tissues at the biochemical and histologic level in MPS I cats but an improved tissue distribution and prevention of a significant immune response could make the therapy more effective.


Assuntos
Iduronidase/uso terapêutico , Mucopolissacaridose I/tratamento farmacológico , Animais , Encéfalo/metabolismo , Gatos , Glicosaminoglicanos/metabolismo , Iduronidase/administração & dosagem , Iduronidase/genética , Iduronidase/metabolismo , Imunoglobulina G/biossíntese , Infusões Intravenosas , Córtex Renal/metabolismo , Córtex Renal/ultraestrutura , Fígado/metabolismo , Fígado/ultraestrutura , Mucopolissacaridose I/patologia , Proteínas Recombinantes/uso terapêutico , Baço/metabolismo , Baço/ultraestrutura , Distribuição Tecidual
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