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1.
Proc Natl Acad Sci U S A ; 121(13): e2313897121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38466875

RESUMEN

Although the last several decades have seen a dramatic reduction in emissions from vehicular exhaust, nonexhaust emissions (e.g., brake and tire wear) represent an increasingly significant class of traffic-related particulate pollution. Aerosol particles emitted from the wear of automotive brake pads contribute roughly half of the particle mass attributed to nonexhaust sources, while their relative contribution to urban air pollution overall will almost certainly grow coinciding with vehicle fleet electrification and the transition to alternative fuels. To better understand the implications of this growing prominence, a more thorough understanding of the physicochemical properties of brake wear particles (BWPs) is needed. Here, we investigate the electrical properties of BWPs as emitted from ceramic and semi-metallic brake pads. We show that up to 80% of BWPs emitted are electrically charged and that this fraction is strongly dependent on the specific brake pad material used. A dependence of the number of charges per particle on charge polarity and particle size is also demonstrated. We find that brake wear produces both positive and negative charged particles that can hold in excess of 30 elementary charges and show evidence that more negative charges are produced than positive. Our results will provide insights into the currently limited understanding of BWPs and their charging mechanisms, which potentially have significant implications on their atmospheric lifetimes and thus their relevance to climate and air quality. In addition, our study will inform future efforts to remove BWP emissions before entering the atmosphere by taking advantage of their electric charge.

2.
Ann Neurol ; 91(3): 342-352, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35067959

RESUMEN

OBJECTIVE: The study was undertaken to assess the impact of B cell depletion on humoral and cellular immune responses to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccination in patients with various neuroimmunologic disorders on anti-CD20 therapy. This included an analysis of the T cell vaccine response to the SARS-CoV-2 Delta variant. METHODS: We investigated prospectively humoral and cellular responses to SARS-CoV-2 mRNA vaccination in 82 patients with neuroimmunologic disorders on anti-CD20 therapy and 82 age- and sex-matched healthy controls. For quantification of antibodies, the Elecsys anti-SARS-CoV-2 viral spike (S) immunoassay against the receptor-binding domain (RBD) was used. IFN-gamma enzyme-linked immunosorbent spot assays were performed to assess T cell responses against the SARS-CoV-2 Wuhan strain and the Delta variant. RESULTS: SARS-CoV-2-specific antibodies were found less frequently in patients (70% [57/82]) compared with controls (82/82 [100%], p < 0.001). In patients without detectable B cells (<1 B cell/mcl), seroconversion rates and antibody levels were lower compared to nondepleted (≥1 B cell/mcl) patients (p < 0.001). B cell levels ≥1 cell/mcl were sufficient to induce seroconversion in our cohort of anti-CD20 treated patients. In contrast to the antibody response, the T-cell response against the Wuhan strain and the Delta variant was more pronounced in frequency (p < 0.05) and magnitude (p < 0.01) in B-cell depleted compared to nondepleted patients. INTERPRETATION: Antibody responses to SARS-CoV-2 mRNA vaccinnation can be attained in patients on anti-CD20 therapy by the onset of B cell repopulation. In the absence of B cells, a strong T cell response is generated which may help to protect against severe coronavirus disease 2019 (COVID-19) in this high-risk population. ANN NEUROL 2022;91:342-352.


Asunto(s)
Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Linfocitos B/inmunología , Vacunas contra la COVID-19/administración & dosificación , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , SARS-CoV-2/inmunología , Adulto , Enfermedades Autoinmunes del Sistema Nervioso/sangre , Enfermedades Autoinmunes del Sistema Nervioso/epidemiología , Linfocitos B/metabolismo , COVID-19/epidemiología , COVID-19/prevención & control , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroinmunomodulación/inmunología , Estudios Prospectivos , SARS-CoV-2/metabolismo
3.
Ann Neurol ; 92(3): 476-485, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35703428

RESUMEN

OBJECTIVE: Patients with myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) suffer from severe optic neuritis (ON) leading to retinal neuro-axonal loss, which can be quantified by optical coherence tomography (OCT). We assessed whether ON-independent retinal atrophy can be detected in MOGAD. METHODS: Eighty patients with MOGAD and 139 healthy controls (HCs) were included. OCT data was acquired with (1) Spectralis spectral domain OCT (MOGAD: N = 66 and HCs: N = 103) and (2) Cirrus high-definition OCT (MOGAD: N = 14 and HCs: N = 36). Macular combined ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were quantified. RESULTS: At baseline, GCIPL and pRNFL were lower in MOGAD eyes with a history of ON (MOGAD-ON) compared with MOGAD eyes without a history of ON (MOGAD-NON) and HCs (p < 0.001). MOGAD-NON eyes had lower GCIPL volume compared to HCs (p < 0.001) in the Spectralis, but not in the Cirrus cohort. Longitudinally (follow-up up to 3 years), MOGAD-ON with ON within the last 6-12 months before baseline exhibited greater pRNFL thinning than MOGAD-ON with an ON greater than 12 months ago (p < 0.001). The overall MOGAD cohort did not exhibit faster GCIPL thinning compared with the HC cohort. INTERPRETATION: Our study suggests the absence of attack-independent retinal damage in patients with MOGAD. Yet, ongoing neuroaxonal damage or edema resolution seems to occur for up to 12 months after ON, which is longer than what has been reported with other ON forms. These findings support that the pathomechanisms underlying optic nerve involvement and the evolution of OCT retinal changes after ON is distinct in patients with MOGAD. ANN NEUROL 2022;92:476-485.


Asunto(s)
Síndromes de Inmunodeficiencia/complicaciones , Glicoproteína Mielina-Oligodendrócito/inmunología , Neuritis Óptica/complicaciones , Degeneración Retiniana/etiología , Estudios de Casos y Controles , Estudios de Cohortes , Humanos , Estudios Longitudinales , Neuritis Óptica/diagnóstico por imagen , Neuritis Óptica/etiología , Retina/diagnóstico por imagen , Neuronas Retinianas , Tomografía de Coherencia Óptica/métodos
4.
Nervenarzt ; 94(8): 725-733, 2023 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-36695893

RESUMEN

Over the past 5 years both media and scientific interest has surged regarding the disorder myalgic encephalomyelitis and chronic fatigue syndrome (ME/CFS), not least because of the clinically similar manifestation in long COVID or post-COVID. In this review we discuss the process of clinical diagnosis and randomized controlled therapeutic studies on ME/CFS, and the similarities or differences to long COVID and post-COVID. So far, neither clear pathophysiologically causal nor therapeutic evidence-based results on ME/CFS have been identified in the many years of scientific research. Given the evident psychiatric comorbidity rates in patients with a diagnosis of ME/CFS, a psychosomatic etiology of this syndrome should be considered. Furthermore, a precise and reliable diagnostic classification based on stricter criteria would benefit both pathophysiological and therapeutic research.


Asunto(s)
COVID-19 , Síndrome de Fatiga Crónica , Humanos , Síndrome de Fatiga Crónica/diagnóstico , Síndrome de Fatiga Crónica/terapia , Síndrome de Fatiga Crónica/epidemiología , Síndrome Post Agudo de COVID-19 , COVID-19/complicaciones , Comorbilidad
5.
Radiology ; 303(1): 141-150, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34981978

RESUMEN

Background MR spectroscopic imaging (MRSI) allows in vivo assessment of brain metabolism and is of special interest in multiple sclerosis (MS), where morphologic MRI cannot depict major parts of disease activity. Purpose To evaluate the ability of 7.0-T MRSI to depict and visualize pathologic alterations in the normal-appearing white matter (NAWM) and cortical gray matter (CGM) in participants with MS and to investigate their relation to disability. Materials and Methods Free-induction decay MRSI was performed at 7.0 T. Participants with MS and age- and sex-matched healthy controls were recruited prospectively between January 2016 and December 2017. Metabolic ratios were obtained in white matter lesions, NAWM, and CGM regions. Subgroup analysis for MS-related disability based on Expanded Disability Status Scale (EDSS) scores was performed using analysis of covariance. Partial correlations were applied to explore associations between metabolic ratios and disability. Results Sixty-five participants with MS (mean age ± standard deviation, 34 years ± 9; 34 women) and 20 age- and sex-matched healthy controls (mean age, 32 years ± 7; 11 women) were evaluated. Higher signal intensity of myo-inositol (mI) with and without reduced signal intensity of N-acetylaspartate (NAA) was visible on metabolic images in the NAWM of participants with MS. A higher ratio of mI to total creatine (tCr) was observed in the NAWM of the centrum semiovale of all MS subgroups, including participants without disability (marginal mean ± standard error, healthy controls: 0.78 ± 0.04; EDSS 0-1: 0.86 ± 0.03 [P = .02]; EDSS 1.5-3: 0.95 ± 0.04 [P < .001]; EDSS ≥3.5: 0.94 ± 0.04 [P = .001]). A lower ratio of NAA to tCr was found in MS subgroups with disabilities, both in their NAWM (marginal mean ± standard error, healthy controls: 1.46 ± 0.04; EDSS 1.5-3: 1.33 ± 0.03 [P = .03]; EDSS ≥3.5: 1.30 ± 0.04 [P = .01]) and CGM (marginal mean ± standard error, healthy controls: 1.42 ± 0.05; EDSS ≥3.5: 1.23 ± 0.05 [P = .006]). mI/NAA correlated with EDSS (NAWM of centrum semiovale: r = 0.47, P < .001; parietal NAWM: r = 0.43, P = .002; frontal NAWM: r = 0.34, P = .01; frontal CGM: r = 0.37, P = .004). Conclusion MR spectroscopic imaging at 7.0 T allowed in vivo visualization of multiple sclerosis pathologic findings not visible at T1- or T2-weighted MRI. Metabolic abnormalities in the normal-appearing white matter and cortical gray matter were associated with disability. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Barker in this issue.


Asunto(s)
Personas con Discapacidad , Esclerosis Múltiple , Sustancia Blanca , Adulto , Encéfalo/patología , Creatina/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Esclerosis Múltiple/patología , Receptores de Antígenos de Linfocitos T/metabolismo , Sustancia Blanca/patología
6.
Mult Scler ; 28(6): 942-949, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34595974

RESUMEN

BACKGROUND: Epilepsy development during the course of multiple sclerosis (MS) is considered to be the result of cortical pathology. However, no long-term data exist on whether epilepsy in MS also leads to increasing disability over time. OBJECTIVE: To examine if epilepsy leads to more rapid disease progression. METHODS: We analyzed the data of 31,052 patients on the German Multiple Sclerosis Register in a case-control study. RESULTS: Secondary progressive disease course (odds ratio (OR) = 2.23), age (OR = 1.12 per 10 years), and disability (OR = 1.29 per Expanded Disability Status Scale (EDSS) point) were associated with the 5-year prevalence of epilepsy. Patients who developed epilepsy during the course of the disease had a higher EDSS score at disease onset compared to matched control patients (EDSS 2.0 vs 1.5), progressed faster in each dimension, and consequently showed higher disability (EDSS 4.4 vs 3.4) and lower employment status (40% vs 65%) at final follow-up. After 15 years of MS, 64% of patients without compared to 54% of patients with epilepsy were not severely limited in walking distance. CONCLUSION: This work highlights the association of epilepsy on disability progression in MS, and the need for additional data to further clarify the underlying mechanisms.


Asunto(s)
Personas con Discapacidad , Epilepsia , Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple , Estudios de Casos y Controles , Niño , Evaluación de la Discapacidad , Progresión de la Enfermedad , Epilepsia/epidemiología , Epilepsia/etiología , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple Crónica Progresiva/epidemiología
7.
Mult Scler ; 28(6): 865-871, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34449299

RESUMEN

OBJECTIVE: To investigate the time to diagnosis in multiple sclerosis (MS) in Germany. METHODS: Analysis of real-world registry data from the German Multiple Sclerosis Registry (GMSR) and performing a primary analysis in patients where month-specific registration of the dates of onset and diagnosis was available. RESULTS: As of January 2020, data of a total of 28,658 patients with MS were extracted from the GMSR, with 9836 patients included in the primary analysis. The mean time to diagnosis was shorter following the introduction of the first magnetic resonance imaging (MRI)-based McDonald criteria in 2001. This effect was most pronounced in younger adults below the age of 40 years with relapsing onset multiple sclerosis (ROMS), with a decrease from 1.9 years in 2010 to 0.9 years in 2020, while unchanged in patients aged 40-50 years (1.4 years in 2010 and 1.3 years in 2020). In the limited number of paediatric onset MS patients, the time to diagnosis was longer and did not change (2.9 years). CONCLUSION: The current sensitive MRI-based diagnostic criteria have likely contributed to an earlier diagnosis of MS in Germany in younger adults aged 18-39 years with ROMS. Whether this translated to earlier initiation of disease-modifying treatment or had a beneficial effect on patient outcomes remains to be demonstrated.


Asunto(s)
Esclerosis Múltiple , Adulto , Niño , Diagnóstico Precoz , Alemania/epidemiología , Humanos , Imagen por Resonancia Magnética , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/epidemiología , Sistema de Registros
8.
Eur J Neurol ; 28(10): 3503-3516, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33090599

RESUMEN

OBJECTIVE: The outbreak of the SARS-CoV-2 pandemic, caused by a previously unknown infectious agent, posed unprecedented challenges to healthcare systems and unmasked their vulnerability and limitations worldwide. Patients with long-term immunomodulatory/suppressive therapies, as well as their physicians, were and are concerned about balancing the risk of infection and effects of disease-modifying therapy. Over the last few months, knowledge regarding SARS-CoV-2 has been growing tremendously, and the first experiences of infections in patients with multiple sclerosis (MS) have been reported. METHODS: This review summarizes the currently still limited knowledge about SARS-CoV-2 immunology and the commonly agreed modes of action of approved drugs in immune-mediated diseases of the central nervous system (MS and neuromyelitis optica spectrum disorder). Specifically, we discuss whether immunosuppressive/immunomodulatory drugs may increase the risk of SARS-CoV-2 infection and, conversely, may decrease the severity of a COVID-19 disease course. RESULTS: At present, it can be recommended in general that none of those therapies with a definite indication needs to be stopped per se. A possibly increased risk of infection for most medications is accompanied by the possibility to reduce the severity of COVID-19. CONCLUSIONS: Despite the knowledge gain over the last few months, current evidence remains limited, and, thus, further clinical vigilance and systematic documentation is essential.


Asunto(s)
COVID-19 , Esclerosis Múltiple , Neuromielitis Óptica , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/epidemiología , Neuromielitis Óptica/epidemiología , Pandemias , SARS-CoV-2
9.
Eur J Neurol ; 28(9): 3173-3176, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34242461

RESUMEN

BACKGROUND AND PURPOSE: Prevalence data are needed to reveal trends regarding the pediatric multiple sclerosis (MS) situation worldwide. The aim was to identify changes in MS diagnosis prevalence in pediatric patients over a 10-year period in Germany. METHODS: This analysis is based on nationwide outpatient claims data of children aged <18 years covered by the German statutory health insurance (n = 11,381,939 in 2018). People with MS (PwMS) had ≥1 documented MS diagnosis (International Classification of Diseases, 10th Revision, German modification code G35.x). The annual pediatric MS diagnosis prevalence was analyzed regarding age, sex, and place of residence during 2009-2018. RESULTS: The prevalence of pediatric MS developed from 5.3 (2009) to 5.4 (2018)/100,000 insured population aged <18 years. The MS prevalence in patients aged 15-17 years showed a moderate increase over 10 years (19.6-22.7/100,000), whereas patients ≤14 years old showed a slight decrease (1.9-1.7/100,000). The sex ratio (female:male) in 2018 was relatively balanced in PwMS aged ≤14 years (1.32) but female-dominated in those aged 15-17 years (2.47). The formerly different prevalence of pediatric MS between East and West Germany has converged since 2012. CONCLUSIONS: So far, this is the largest study of pediatric MS prevalence in terms of source population size (87% of German children <18 years of age, n = 11,381,939 in 2018) and study period (2009-2018) worldwide. The analyses revealed an increase in MS prevalence and a female-dominated sex ratio in "older" adolescents compared to younger patients.


Asunto(s)
Esclerosis Múltiple , Adolescente , Niño , Femenino , Alemania/epidemiología , Humanos , Masculino , Esclerosis Múltiple/epidemiología , Programas Nacionales de Salud , Prevalencia , Razón de Masculinidad
10.
Proc Natl Acad Sci U S A ; 115(37): 9122-9127, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30154167

RESUMEN

Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes <10 nm, where coagulation losses to larger aerosol particles are greatest. Recent results show that some oxidation products from biogenic volatile organic compounds are major contributors to particle formation and initial growth. However, whether oxidized organics contribute to particle growth over the broad span of tropospheric temperatures remains an open question, and quantitative mass balance for organic growth has yet to be demonstrated at any temperature. Here, in experiments performed under atmospheric conditions in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN), we show that rapid growth of organic particles occurs over the range from [Formula: see text]C to [Formula: see text]C. The lower extent of autoxidation at reduced temperatures is compensated by the decreased volatility of all oxidized molecules. This is confirmed by particle-phase composition measurements, showing enhanced uptake of relatively less oxygenated products at cold temperatures. We can reproduce the measured growth rates using an aerosol growth model based entirely on the experimentally measured gas-phase spectra of oxidized organic molecules obtained from two complementary mass spectrometers. We show that the growth rates are sensitive to particle curvature, explaining widespread atmospheric observations that particle growth rates increase in the single-digit-nanometer size range. Our results demonstrate that organic vapors can contribute to particle growth over a wide range of tropospheric temperatures from molecular cluster sizes onward.

11.
Curr Opin Neurol ; 33(3): 286-294, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32374570

RESUMEN

PURPOSE OF REVIEW: To summarize the currently known side effects of the approved therapies of multiple sclerosis and to suggest monitoring procedures. RECENT FINDINGS: The progress in the treatment of multiple sclerosis with new very effective therapies is accompanied by a number of side effects. Some of these have already been described in the approval studies, but some only after approval in a real world situation. The reason for this is the short duration of the clinical studies, the very heterogeneous patient profile in the real world setting with a number of comorbidities, pretherapies, and wider age range. The side effects may occur during application of therapies or afterwards during the course of the treatment. The side effects may range from mild infections, mild laboratory abnormalities, secondary autoimmune diseases to life-threatening side effects such as progressive multifocal leukoencephalopathy. SUMMARY: It has to be pointed out that these side effects are not to be considered as final and neurologists should be vigilant against new unknown side effects. The doctor should be aware of these undesirable effects, should weigh the benefits of the therapies against the risks, but at the same time she/he should keep in mind that multiple sclerosis can be a very disabling disease if not treated properly.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Factores Inmunológicos/efectos adversos , Leucoencefalopatía Multifocal Progresiva/inducido químicamente , Esclerosis Múltiple/tratamiento farmacológico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/terapia , Femenino , Humanos , Factores Inmunológicos/uso terapéutico , Leucoencefalopatía Multifocal Progresiva/prevención & control , Leucoencefalopatía Multifocal Progresiva/terapia , Masculino
12.
J Neuroinflammation ; 17(1): 261, 2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32883348

RESUMEN

BACKGROUND: New-generation cell-based assays have demonstrated a robust association of serum autoantibodies to full-length human myelin oligodendrocyte glycoprotein (MOG-IgG) with (mostly recurrent) optic neuritis, myelitis, and brainstem encephalitis, as well as with neuromyelitis optica (NMO)-like or acute-disseminated encephalomyelitis (ADEM)-like presentations. However, only limited data are yet available on cerebrospinal fluid (CSF) findings in MOG-IgG-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disease, MOGAD). OBJECTIVE: To describe systematically the CSF profile in MOG-EM. MATERIAL AND METHODS: Cytological and biochemical findings (including white cell counts and differentiation; frequency and patterns of oligoclonal bands; IgG/IgM/IgA and albumin concentrations and CSF/serum ratios; intrathecal IgG/IgA/IgM fractions; locally produced IgG/IgM/IgA concentrations; immunoglobulin class patterns; IgG/IgA/IgM reibergrams; Link index; measles/rubella/zoster (MRZ) reaction; other anti-viral and anti-bacterial antibody indices; CSF total protein; CSF L-lactate) from 163 lumbar punctures in 100 adult patients of mainly Caucasian descent with MOG-EM were analyzed retrospectively. RESULTS: Most strikingly, CSF-restricted oligoclonal IgG bands, a hallmark of multiple sclerosis (MS), were absent in almost 90% of samples (N = 151), and the MRZ reaction, the most specific laboratory marker of MS known so far, in 100% (N = 62). If present, intrathecal IgG (and, more rarely, IgM) synthesis was low, often transient and mostly restricted to acute attacks. CSF WCC was elevated in > 50% of samples (median 31 cells/µl; mostly lymphocytes and monocytes; > 100/µl in 12%). Neutrophils were present in > 40% of samples; activated lymphocytes were found less frequently and eosinophils and/or plasma cells only very rarely (< 4%). Blood-CSF barrier dysfunction (as indicated by an elevated albumin CSF/serum ratio) was present in 48% of all samples and at least once in 55% of all patients (N = 88) tested. The frequency and degree of CSF alterations were significantly higher in patients with acute myelitis than in patients with acute ON and varied strongly depending on attack severity. CSF L-lactate levels correlated significantly with the spinal cord lesion load in patients with acute myelitis (p < 0.0001). Like pleocytosis, blood-CSF barrier dysfunction was present also during remission in a substantial number of patients. CONCLUSION: MOG-IgG-positive EM is characterized by CSF features that are distinct from those in MS. Our findings are important for the differential diagnosis of MS and MOG-EM and add to the understanding of the immunopathogenesis of this newly described autoimmune disease.


Asunto(s)
Autoanticuerpos/líquido cefalorraquídeo , Encefalomielitis/inmunología , Inmunoglobulinas/líquido cefalorraquídeo , Glicoproteína Mielina-Oligodendrócito/inmunología , Adolescente , Adulto , Anciano , Autoanticuerpos/sangre , Encefalomielitis/sangre , Encefalomielitis/líquido cefalorraquídeo , Femenino , Humanos , Inmunoglobulinas/sangre , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Punción Espinal , Adulto Joven
13.
Dig Dis Sci ; 65(11): 3408-3409, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32990865

RESUMEN

The original version of the article unfortunately contained an error in the legend of Figure 5B. Corrected version of Figure 5 is given below.

14.
Dig Dis Sci ; 65(10): 2834-2843, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31897897

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS), a common hormonal disorder in women, affects 4-18% of women of reproductive age worldwide. A higher prevalence of irritable bowel syndrome was found in women with PCOS. However, the effects and mechanism of PCOS on stomach and colon contractility remain unclear. AIMS: This study aims to evaluate the correlation between PCOS and gastrointestinal disorder. METHODS: Four-week-old female rats were subcutaneously implanted with pellets containing 7.5 mg of dihydrotestosterone for 13 weeks to create PCOS rat models. After vaginal smears, the estrus cycle stage was evaluated. Oral glucose tolerance test was performed after 90 days of treatment. All animals were killed at 17 weeks. The rats were fasted overnight and then anesthetized before decapitation, and the stomach fundus and colon were surgically removed and cultured in oxygenated Krebs solution. Acetylcholine and carbachol were used to evaluate the cholinergic system on contractility. RESULTS: The basal and stomach fundus responded with a reduced frequency and contractility in response to acetylcholine in the PCOS group. Moreover, no difference was found in the spontaneous stomach contractility induced by carbachol in both groups. Lower maximal colon muscle contractility was also found in response to acetylcholine stimulation in PCOS rats. Furthermore, lower maximal muscle contractility was found in response to extracellular calcium levels. MLC20 phosphorylation was also reduced in the gastrointestinal tissue in PCOS rats. CONCLUSIONS: PCOS induces gastroparesis and reduces gastrointestinal muscle contractility. This effect is, at least partly, through reducing the responsiveness of acetylcholine and MLC20 phosphorylation.


Asunto(s)
Colon/fisiopatología , Enfermedades Gastrointestinales/fisiopatología , Motilidad Gastrointestinal , Contracción Muscular , Músculo Liso/fisiopatología , Síndrome del Ovario Poliquístico/complicaciones , Estómago/fisiopatología , Acetilcolina/farmacología , Animales , Señalización del Calcio , Carbacol/farmacología , Colon/efectos de los fármacos , Colon/metabolismo , Dihidrotestosterona , Modelos Animales de Enfermedad , Femenino , Enfermedades Gastrointestinales/etiología , Enfermedades Gastrointestinales/metabolismo , Motilidad Gastrointestinal/efectos de los fármacos , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Cadenas Ligeras de Miosina/metabolismo , Fosforilación , Síndrome del Ovario Poliquístico/inducido químicamente , Ratas Sprague-Dawley , Estómago/efectos de los fármacos
16.
J Cell Physiol ; 232(8): 2135-2144, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27886378

RESUMEN

The increasing intensity of exercise enhanced corticosterone and lactate production in both humans and rodents. Our previous studies also demonstrated that lactate could stimulate testosterone production in vivo and in vitro. However, the production of testosterone in response to combined corticosterone and lactate on Leydig cells, and underlying molecular mechanisms are remained unclear. This study investigated the changes in testosterone levels of Leydig cells upon exposure to lactate, corticosterone or combination of both, and revealed the detailed mechanisms. Leydig cells were isolated from rat testes, and treated with different concentrations of lactate (2.5-20 mM), cortiosterone (10-9 -10-4 M) and lactate plus corticosterone. The production of testosterone were assayed by radioimmunoassay, and the key molecular proteins, including luteinizing hormone receptor (LHR), protein kinase A (PKA), steroidogenic acute regulatory protein (StAR), and cholesterol P450 side-chain cleavage enzyme (P450scc) involved in testosterone production were performed by Western blot. Results showed that testosterone levels were significantly increased with lactate, while decresed with corticosterone and lactate plus corticosterone treatment. Protein expressions of LHR and P450scc were upregulated with lactate treatment. However, PKA and P450scc were downregulated by lactate plus corticosterone treatment. This downregulation was followed by decreased testoterone levels in Leydig cells. Furthermore, acetylated cAMP, which activates testosterone production was increased with lactate, but not altered by conrtiosterone. Our findings conclude that corticosterone may interfere with lactate, and restrict lactate-stimulated testosterone production in Leydig cells. J. Cell. Physiol. 232: 2135-2144, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Corticosterona/farmacología , Ácido Láctico/farmacología , Células Intersticiales del Testículo/efectos de los fármacos , Testosterona/metabolismo , Animales , Células Cultivadas , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Células Intersticiales del Testículo/metabolismo , Masculino , Ratas Sprague-Dawley , Receptores de HL/efectos de los fármacos , Receptores de HL/metabolismo , Sistemas de Mensajero Secundario/efectos de los fármacos
17.
Artículo en Inglés | MEDLINE | ID: mdl-28760897

RESUMEN

The aim of this study was to develop a population pharmacokinetic (PK) model for teicoplanin across childhood age ranges to be used as Bayesian prior information in the software constructed for individualized therapy. We developed a nonparametric population model fitted to PK data from neonates, infants, and older children. We then implemented this model in the BestDose multiple-model Bayesian adaptive control algorithm to show its clinical utility. It was used to predict the dosages required to achieve optimal teicoplanin predose targets (15 mg/liter) from day 3 of therapy. We performed individual simulations for an infant and a child from the original population, who provided early first dosing interval concentration-time data. An allometric model that used weight as a measure of size and that also incorporated renal function using the estimated glomerular filtration rate (eGFR), or the ratio of postnatal age (PNA) to serum creatinine concentration (SCr) for infants <3 months old, best described the data. The median population PK parameters were as follows: elimination rate constant (Ke) = 0.03 · (wt/70)-0.25 · Renal (h-1); V = 19.5 · (wt/70) (liters); Renal = eGFR0.07 (ml/min/1.73 m2), or Renal = PNA/SCr (µmol/liter). Increased teicoplanin dosages and alternative administration techniques (extended infusions and fractionated multiple dosing) were required in order to achieve the targets safely by day 3 in simulated cases. The software was able to predict individual measured concentrations and the dosages and administration techniques required to achieve the desired target concentrations early in therapy. Prospective evaluation is now needed in order to ensure that this individualized teicoplanin therapy approach is applicable in the clinical setting. (This study has been registered in the European Union Clinical Trials Register under EudraCT no. 2012-005738-12.).


Asunto(s)
Antibacterianos/farmacocinética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Teicoplanina/farmacocinética , Adolescente , Algoritmos , Antibacterianos/sangre , Antibacterianos/uso terapéutico , Teorema de Bayes , Niño , Preescolar , Creatinina/sangre , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Método de Montecarlo , Programas Informáticos , Teicoplanina/sangre , Teicoplanina/uso terapéutico
19.
Chin J Physiol ; 60(2): 97-105, 2017 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-28466626

RESUMEN

Food or calorie restriction (FR or CR) induces several physiological changes including weight loss, metabolic adaptations, mineral and hormonal changes. However, the effects of FR on aldosterone steroidogenesis in zona glomerulosa (ZG) cells have not been elucidated. Therefore, the present study was designed to investigate the effects of FR on aldosterone secretion and the involved mechanisms in ovariectomized (Ovx) rats. Ovx rats were divided into ad libitum fed (control) and FR groups. The FR rats exhibited decreased body weight, water intake, urine flow, sodium excretion and increased plasma aldosterone in comparison with control rats. FR elevated the basal and angiotensin II-stimulated aldosterone secretion from ZG cells. The conversions of 25-hydroxy-cholesterol to pregnenolone or corticosterone to aldosterone in ZG cells of FR group were greater than that in control group. FR group had a higher protein expression of steroidogenic acute regulatory (StAR) protein in ZG cells. However, there was no different protein expression of cytochrome P450 sidechain cleavage enzyme (P450scc) in ZG cells between control and FR groups. In summary, the increased activities of P450scc and aldosterone synthase as well as the protein expression of StAR protein in ZG cells are involved in the effects of FR on aldosterone steroidogenesis in Ovx rats. We also suggest that the increase of aldosterone might be associated with anti-diuresis and antinatriuresis in FR group. These results are helpful for understanding the role of aldosterone in physiological adaptation and renal sodium conservation during FR.


Asunto(s)
Aldosterona/biosíntesis , Aldosterona/sangre , Restricción Calórica/métodos , Privación de Alimentos/fisiología , Sodio/orina , Zona Glomerular/metabolismo , Animales , Femenino , Ovariectomía , Ratas , Ratas Sprague-Dawley
20.
Int J Mol Sci ; 18(8)2017 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-28800066

RESUMEN

Therapeutic options to treat multiple sclerosis (MS) relapses comprise glucocorticosteroids (GCS) as first-line and therapeutic plasma exchange (TPE) as second-line treatments in GCS-unresponsive patients. No guidelines exist for the treatment of another relapse following TPE. We retrospectively analyzed the responsiveness to GCS in a subsequent relapse following TPE in previously GCS-unresponsive MS patients. Thirty-seven patients with GCS-unresponsive MS relapses received TPE (relapse A). All patients developed another relapse after the completion of TPE and received GCS again (relapse B). The primary study endpoint was the clinical response to GCS and TPE. Marked improvement was defined as clinically significant improvement in function, moderate improvement as a definite change of symptoms without significant impact on function, no effect comprised unchanged symptoms, and deterioration a worsening of symptoms or new deficits. The secondary endpoint was an improvement in expanded disability status scale (EDSS) scoring. All patients were GCS-unresponsive during relapse A and received TPE. During GCS treatment of relapse B, marked improvement was observed in 10, moderate improvement in 24, and no effect in three patients. The EDSS decreased in 15 patients. GCS might remain the first-line relapse treatment following TPE in formerly GCS-unresponsive MS patients.


Asunto(s)
Corticoesteroides/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Intercambio Plasmático/efectos adversos , Adolescente , Corticoesteroides/administración & dosificación , Adulto , Anciano , Humanos , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/terapia , Intercambio Plasmático/métodos
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