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1.
Phys Rev Lett ; 131(5): 051801, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595210

RESUMEN

MINERvA has measured the ν_{µ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{µ} energies and at produced π^{+} energies and angles, E_{π}>1 GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10 GeV.

2.
Phys Rev Lett ; 131(1): 011801, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478458

RESUMEN

Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high statistic differential cross sections are reported for the semiexclusive reaction ν_{µ}A→µ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{µ} beam with ⟨E_{ν}⟩≈6 GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.

3.
Phys Rev Lett ; 130(16): 161801, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37154647

RESUMEN

This Letter presents the first simultaneous measurement of the quasielasticlike neutrino-nucleus cross sections on C, water, Fe, Pb, and scintillator (hydrocarbon or CH) as a function of longitudinal and transverse muon momentum. The ratio of cross sections per nucleon between Pb and CH is always above unity and has a characteristic shape as a function of transverse muon momentum that evolves slowly as a function of longitudinal muon momentum. The ratio is constant versus longitudinal momentum within uncertainties above a longitudinal momentum of 4.5 GeV/c. The cross section ratios to CH for C, water, and Fe remain roughly constant with increasing longitudinal momentum, and the ratios between water or C to CH do not have any significant deviation from unity. Both the overall cross section level and the shape for Pb and Fe as a function of transverse muon momentum are not reproduced by current neutrino event generators. These measurements provide a direct test of nuclear effects in quasielasticlike interactions, which are major contributors to long-baseline neutrino oscillation data samples.

5.
Nature ; 614(7946): 48-53, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725994

RESUMEN

Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams1. The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon2. Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, FA, can be measured from neutrino scattering from free nucleons, νµn → µ-p and [Formula: see text], as a function of the negative four-momentum transfer squared (Q2). Up to now, FA(Q2) has been extracted from the bound nucleons in neutrino-deuterium scattering3-9, which requires uncertain nuclear corrections10. Here we report the first high-statistics measurement, to our knowledge, of the [Formula: see text] cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA11 experiment, extracting FA from free proton targets and measuring the nucleon axial charge radius, rA, to be 0.73 ± 0.17 fm. The antineutrino-hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations12-15. Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments16-20 to better constrain neutrino interaction models.

6.
Exp Clin Endocrinol Diabetes ; 130(11): 704-713, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36084942

RESUMEN

OBJECTIVE: To identify early available predictors for the long-term outcome of patients after transsphenoidal surgery (TSS) in the management of Cushing's disease. METHODS: This single-center, retrospective study included 93 consecutive patients with Cushing's disease (follow-up 12-129 months, mean 48, median 38) who underwent TSS (21 had previous operations elsewhere). Six cases had early re-operation, and the resulting data were evaluated instead of the respective first operation. During the postoperative course, serum cortisol levels were assessed every four hours at least until the next morning. An association of parameters with long-term outcomes was tested using binary logistic regression. Receiver operating characteristic curves were used to determine sensitivity, specificity, positive predictive value, and negative predictive value of different cut-off values of serum cortisol in the postoperative course in the event of recurrence after remission. RESULTS: Eighty out of 93 patients (86%) showed postoperative remission (after primary treatment, 60 out of 72 patients, 90.3%). Of these, 8 patients (10%) developed recurrence of hypercortisolism. Compared to patients with persisting long-term remission, those with recurrence differed in cortisol levels starting from 4 pm on the day of surgery plus an event of increasing cortisol during the early postoperative course ("peak"). Binary logistic regression showed the association between a peak of serum cortisol in the early postoperative course with an increased probability of recurrence. CONCLUSIONS: Patients with a peak of serum cortisol in the early postoperative course show an increased recurrence rate. A cut-off value of serum cortisol for clear identification of patients with later recurrence could not be determined.


Asunto(s)
Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT) , Humanos , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/cirugía , Hidrocortisona , Estudios Retrospectivos , Resultado del Tratamiento , Periodo Posoperatorio , Estudios de Seguimiento
7.
Phys Rev Lett ; 129(2): 021803, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35867435

RESUMEN

Neutrino charged-current quasielastic-like scattering, a reaction category extensively used in neutrino oscillation measurements, probes nuclear effects that govern neutrino-nucleus interactions. This Letter reports the first measurement of the triple-differential cross section for ν_{µ} quasielastic-like reactions using the hydrocarbon medium of the MINERvA detector exposed to a wideband beam spanning 2≤E_{ν}≤20 GeV. The measurement maps the correlations among transverse and longitudinal muon momenta and summed proton kinetic energies, and compares them to predictions from a state-of-art simulation. Discrepancies are observed that likely reflect shortfalls with modeling of pion and nucleon intranuclear scattering and/or spectator nucleon ejection from struck nuclei. The separate determination of leptonic and hadronic variables can inform experimental approaches to neutrino-energy estimation.

8.
Eur Heart J Cardiovasc Pharmacother ; 8(3): 272-281, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35512362

RESUMEN

AIMS: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by a deficiency of the lysosomal enzyme α-galactosidase A (GLA/AGAL), resulting in the lysosomal accumulation of globotriaosylceramide (Gb3). Patients with amenable GLA mutations can be treated with migalastat, an oral pharmacological chaperone increasing endogenous AGAL activity. In this prospective observational multicentre study, safety as well as cardiovascular, renal, and patient-reported outcomes and disease biomarkers were assessed after 12 and 24 months of migalastat treatment under 'real-world' conditions. METHODS AND RESULTS: A total of 54 patients (26 females) (33 of these [61.1%] pre-treated with enzyme replacement therapy) with amenable mutations were analysed. Treatment was generally safe and well tolerated. A total of 153 events per 1000 patient-years were detected. Overall left ventricular mass index decreased after 24 months (all: -7.5 ± 17.4 g/m2, P = 0.0118; females: -4.6 ± 9.1 g/m2, P = 0.0554; males: -9.9 ± 22.2 g/m2, P = 0.0699). After 24 months, females and males presented with a moderate yearly loss of estimated glomerular filtration rate (-2.6 and -4.4 mL/min/1.73 m2 per year; P = 0.0317 and P = 0.0028, respectively). FD-specific manifestations/symptoms remained stable (all P > 0.05). A total of 76.9% of females and 50% of males suffered from pain, which has not improved under treatment. FD-specific disease scores (Disease Severity Scoring System and Mainz Severity Score Index) remained stable during treatment. AGAL activities and plasma lyso-Gb3 values remained stable, although some male patients presented with increasing lyso-Gb3 levels over time. CONCLUSIONS: Treatment with migalastat was generally safe and resulted in most patients in an amelioration of left ventricular mass. However, due to the heterogeneity of FD phenotypes, it is advisable that the treating physician monitors the clinical response regularly.


Asunto(s)
Enfermedad de Fabry , 1-Desoxinojirimicina/efectos adversos , 1-Desoxinojirimicina/análogos & derivados , Manejo de la Enfermedad , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/tratamiento farmacológico , Enfermedad de Fabry/genética , Femenino , Humanos , Masculino , Estudios Prospectivos
9.
Phys Rev Lett ; 125(13): 131802, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33034464

RESUMEN

We report the final measurement of the neutrino oscillation parameters Δm_{32}^{2} and sin^{2}θ_{23} using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of 23.76×10^{20} protons on target producing ν_{µ} and ν[over ¯]_{µ} beams and 60.75 kt yr exposure to atmospheric neutrinos. The measurement of the disappearance of ν_{µ} and the appearance of ν_{e} events between the Near and Far detectors yields |Δm_{32}^{2}|=2.40_{-0.09}^{+0.08}(2.45_{-0.08}^{+0.07})×10^{-3} eV^{2} and sin^{2}θ_{23}=0.43_{-0.04}^{+0.20}(0.42_{-0.03}^{+0.07}) at 68% C.L. for normal (inverted) hierarchy.

10.
Phys Rev Lett ; 124(12): 121801, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32281855

RESUMEN

We measure neutrino charged-current quasielasticlike scattering on hydrocarbon at high statistics using the wideband Neutrinos at the Main Injector beam with neutrino energy peaked at 6 GeV. The double-differential cross section is reported in terms of muon longitudinal (p_{∥}) and transverse (p_{⊥}) momentum. Cross section contours versus lepton momentum components are approximately described by a conventional generator-based simulation, however, discrepancies are observed for transverse momenta above 0.5 GeV/c for longitudinal momentum ranges 3-5 and 9-20 GeV/c. The single differential cross section versus momentum transfer squared (dσ/dQ_{QE}^{2}) is measured over a four-decade range of Q^{2} that extends to 10 GeV^{2}. The cross section turnover and falloff in the Q^{2} range 0.3-10 GeV^{2} is not fully reproduced by generator predictions that rely on dipole form factors. Our measurement probes the axial-vector content of the hadronic current and complements the electromagnetic form factor data obtained using electron-nucleon elastic scattering. These results help oscillation experiments because they probe the importance of various correlations and final-state interaction effects within the nucleus, which have different effects on the visible energy in detectors.

11.
Clin Pharmacol Ther ; 108(2): 326-337, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32198894

RESUMEN

Fabry's disease (FD) is an X-linked lysosomal storage disorder caused by the deficient activity of the lysosomal enzyme α-galactosidase A (α-Gal A) leading to intracellular accumulation of globotriaosylceramide (Gb3). Patients with amenable mutations can be treated with migalastat, a recently approved oral pharmacologic chaperone to increase endogenous α-Gal A activity. We assessed safety along with cardiovascular, renal, and patient-reported outcomes and disease biomarkers in a prospective observational multicenter study after 12 months of migalastat treatment under "real-world" conditions. Fifty-nine (28 females) patients (34 (57.6%) pretreated with enzyme replacement therapy) with amenable mutations were recruited. Migalastat was generally safe and well tolerated. Females and males presented with a reduction of left ventricular mass index (primary end point) (-7.2 and -13.7 g/m2 , P = 0.0050 and P = 0.0061). FD-specific manifestations and symptoms remained stable (all P > 0.05). Both sexes presented with a reduction of estimated glomerular filtration rate (secondary end point) (-6.9 and -5.0 mL/minute/1.73 m2 ; P = 0.0020 and P = 0.0004, respectively), which was most prominent in patients with low blood pressure (P = 0.0271). α-Gal A activity increased in male patients by 15% from 29% to 44% of the normal wild-type activity (P = 0.0106) and plasma lyso-Gb3 levels were stable in females and males (P = 0.3490 and P = 0.2009). Reevaluation of mutations with poor biochemical response revealed no marked activity increase in a zero activity background. We conclude that therapy with migalastat was generally safe and resulted in an amelioration of left ventricular mass. In terms of impaired renal function, blood pressure control seems to be an unattended important goal.


Asunto(s)
1-Desoxinojirimicina/análogos & derivados , Enfermedad de Fabry/tratamiento farmacológico , alfa-Galactosidasa/metabolismo , 1-Desoxinojirimicina/efectos adversos , 1-Desoxinojirimicina/uso terapéutico , Adulto , Biomarcadores/sangre , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/enzimología , Enfermedad de Fabry/fisiopatología , Femenino , Predisposición Genética a la Enfermedad , Alemania , Tasa de Filtración Glomerular/efectos de los fármacos , Glucolípidos/sangre , Humanos , Masculino , Persona de Mediana Edad , Mutación , Estudios Prospectivos , Esfingolípidos/sangre , Factores de Tiempo , Resultado del Tratamiento , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , alfa-Galactosidasa/genética
12.
Horm Metab Res ; 51(12): 792-797, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31766063

RESUMEN

A lack of vitamin D seems to be related to autoimmune diseases including autoimmune thyroiditis (AIT). This study intends to determine the correlation between improvement of 25-hydroxyvitamin D [25(OH)D] levels and AIT in patients from an outpatient endocrine clinic in Frankfurt, Germany. This study included 933 patients with thyroid peroxidase antibodies (anti-TPO-Ab) ≥34 kIU/l, including most patients with clear AIT due to a concurrent sonographic evidence of reduced echogenicity. We performed clinical evaluation and laboratory analysis at five points in time within two years retrospectively. Due to a high dropout rate within the observation period, we excluded the last two time points from analysis. Data from 933 AIT patients revealed 89% having vitamin D deficiency or insufficiency [25(OH)D <75 nmol/l] with a median 25(OH)D level of 39.7 nmol/l. At baseline, a weak inverse correlation between 25(OH)D and anti-TPO-Ab was observed during winter (rs=-0.09, p=0.048*), but not during summer time (p>0.2). We discovered 58 patients having initially a 25(OH)D level < 75 nmol/l (median: 40.2 nmol/l), which improved over time to a 25(OH)D level ≥ 75 nmol/l (median: 83.2 nmol/l, p<0.0005***). Simultaneously, the median anti-TPO-Ab level showed a significant decrease of 25% from 245.8 to 181.3 kIU/l (p=0.036*). A significant reduction of the median anti-TPO-Ab level of 9% was also observed in the control group, which consisted of patients having constantly a 25(OH)D level <75 nmol/l. The result may suggest that in particular patients with 25(OH)D levels < 75 nmol/l benefit from an increase of 25(OH)D levels ≥ 75 nmol/l. Further prospective randomized controlled clinical trials are needed to finally evaluate if vitamin D has immunmodulatory effects in AIT.


Asunto(s)
Autoanticuerpos/sangre , Tiroiditis Autoinmune/sangre , Vitamina D/análogos & derivados , Adulto , Femenino , Alemania , Humanos , Yoduro Peroxidasa/inmunología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tiroiditis Autoinmune/inmunología , Vitamina D/sangre , Deficiencia de Vitamina D/sangre
14.
Phys Rev Lett ; 121(2): 022504, 2018 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-30085714

RESUMEN

Final-state kinematic imbalances are measured in mesonless production of ν_{µ}+A→µ^{-}+p+X in the MINERvA tracker. Initial- and final-state nuclear effects are probed using the direction of the µ^{-}-p transverse momentum imbalance and the initial-state momentum of the struck neutron. Differential cross sections are compared to predictions based on current approaches to medium modeling. These models underpredict the cross section at intermediate intranuclear momentum transfers that generally exceed the Fermi momenta. As neutrino interaction models need to correctly incorporate the effect of the nucleus in order to predict neutrino energy resolution in oscillation experiments, this result points to a region of phase space where additional cross section strength is needed in current models, and demonstrates a new technique that would be suitable for use in fine-grained liquid argon detectors where the effect of the nucleus may be even larger.

16.
Clin Chim Acta ; 484: 320-322, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29856977

RESUMEN

We report on a 47 year old male patient with multiple sclerosis (MS) presenting in our outpatient neurology clinic in Frankfurt/Main for therapy evaluation. Before change of treatment laboratory investigations were performed. Thyroid function tests (TFTs) with a streptavidin/biotin based immunoassay revealed severe hyperthyroidism with positive thyroid autoantibodies suggestive for Graves' disease. Clinical presentation and thyroid sonography were unremarkable. Due to the discordance between clinical presentation and TFTs, we repeated medical history, in which the patient reported taking high-doses of biotin (300 mg/day) for MS. Recent studies with patients suffering from primary and secondary progressive MS, indicated promising effects of high-dose biotin on MS-related disability. In immunoassays relaying on streptavidin-biotin interaction, biotin intake can cause falsely high or low results. Two weeks after withdrawing biotin, biotin/streptavidin dependant assays showed no longer the biochemical picture of severe hyperthyroidism. Biotin intake should be paused for at least two to five days prior to the use of biotin/streptavidin dependant assays. Alternatively, non-biotin/streptavidin dependant assays (radioimmunoassay, gas chromatography-mass spectrometry/liquid chromatography-mass spectrometry) may be used.


Asunto(s)
Artefactos , Biotina/análisis , Inmunoensayo , Esclerosis Múltiple/diagnóstico , Pruebas de Función de la Tiroides , Glándula Tiroides/metabolismo , Biotina/administración & dosificación , Biotina/uso terapéutico , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/tratamiento farmacológico , Estreptavidina/análisis , Glándula Tiroides/efectos de los fármacos
17.
Phys Rev Lett ; 120(22): 221805, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29906174

RESUMEN

We report on multinucleon effects in low momentum transfer (<0.8 GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.

18.
Phys Rev Lett ; 119(8): 082001, 2017 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-28952766

RESUMEN

Charged-current ν_{µ} interactions on carbon, iron, and lead with a final state hadronic system of one or more protons with zero mesons are used to investigate the influence of the nuclear environment on quasielasticlike interactions. The transferred four-momentum squared to the target nucleus, Q^{2}, is reconstructed based on the kinematics of the leading proton, and differential cross sections versus Q^{2} and the cross-section ratios of iron, lead, and carbon to scintillator are measured for the first time in a single experiment. The measurements show a dependence on the atomic number. While the quasielasticlike scattering on carbon is compatible with predictions, the trends exhibited by scattering on iron and lead favor a prediction with intranuclear rescattering of hadrons accounted for by a conventional particle cascade treatment. These measurements help discriminate between different models of both initial state nucleons and final state interactions used in the neutrino oscillation experiments.

19.
Phys Rev Lett ; 119(1): 011802, 2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28731762

RESUMEN

Neutral-current production of K^{+} by atmospheric neutrinos is a background in searches for the proton decay p→K^{+}ν[over ¯]. Reactions such as νp→νK^{+}Λ are indistinguishable from proton decays when the decay products of the Λ are below detection threshold. Events with K^{+} are identified in MINERvA by reconstructing the timing signature of a K^{+} decay at rest. A sample of 201 neutrino-induced neutral-current K^{+} events is used to measure differential cross sections with respect to the K^{+} kinetic energy, and the non-K^{+} hadronic visible energy. An excess of events at low hadronic visible energy is observed relative to the prediction of the neut event generator. Good agreement is observed with the cross section prediction of the genie generator. A search for photons from π^{0} decay, which would veto a neutral-current K^{+} event in a proton decay search, is performed, and a 2σ deficit of detached photons is observed relative to the genie prediction.

20.
Phys Rev Lett ; 118(22): 221801, 2017 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-28621994

RESUMEN

In a study of a muon-neutrino disappearance at 810 km, the NOvA experiment finds flavor mixing of the atmospheric sector to deviate from maximal (sin^{2}θ_{23}=0.5) by 2.6σ. The result is in tension with the 295-km baseline measurements of T2K, which are consistent with maximal mixing. We propose that θ_{23} is in fact maximal, and that the disagreement is a harbinger of environmentally induced decoherence. The departure from maximal mixing can be accounted for by an energy-independent decoherence of strength Γ=(2.3±1.1)×10^{-23} GeV.

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