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1.
Cureus ; 16(2): e55226, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38558685

RESUMO

We present the case of a lung transplant candidate under veno-venous membrane oxygenation assistance (VV ECMO) whose diagnosis of emphysema of undetermined etiology was redefined as Langerhans cell histiocytosis (LCH) due to a scalp skin biopsy performed years after the beginning of his respiratory symptoms. A 20-year-old patient started three years before his admission with progressive dyspnea leading to a diagnosis of bullous emphysema of undetermined cause, which evolved into respiratory failure and evaluation for bilateral lung transplant. Three years later, he developed bilateral pneumonia requiring mechanical ventilation. When refractory hypoxemia ensued, he had to be placed on VV ECMO. Under these conditions, he was transferred to our center and listed for a bilateral pulmonary transplantation. Forty-eight hours after admission, and due to intense polyuria, central diabetes insipidus was diagnosed. In this clinical context, the presence of cutaneous lesions on the scalp was reconsidered and biopsied under the presumption of possible LCH, with pathology analysis confirming the diagnosis. He continued to be assisted with VV ECMO for 66 more days as a bridge to transplantation, developing multi-organ failure and passing away before a donor organ was available. The diagnosis of LCH should be considered in any adult patient with bullous emphysema of undetermined cause. Given the possibility of early therapeutic interventions, the search for its clinical associations (e.g., diabetes insipidus and/or skin lesions) should be a systematic part of the etiologic workup. The availability of skin specimens to reach a diagnosis makes its thorough search an important part of the diagnostic approach.

2.
Alzheimers Dement ; 20(4): 2397-2407, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38298155

RESUMO

INTRODUCTION: Evidence suggests microglial activation precedes regional tau and neurodegeneration in Alzheimer's disease (AD). We characterized microglia with translocator protein (TSPO) positron emission tomography (PET) within an AD progression model where global amyloid beta (Aß) precedes local tau and neurodegeneration, resulting in cognitive impairment. METHODS: Florbetaben, PBR28, and MK-6240 PET, T1 magnetic resonance imaging, and cognitive measures were performed in 19 cognitively unimpaired older adults and 22 patients with mild cognitive impairment or mild AD to examine associations among microglia activation, Aß, tau, and cognition, adjusting for neurodegeneration. Mediation analyses evaluated the possible role of microglial activation along the AD progression model. RESULTS: Higher PBR28 uptake was associated with higher Aß, higher tau, and lower MMSE score, independent of neurodegeneration. PBR28 mediated associations between tau in early and middle Braak stages, between tau and neurodegeneration, and between neurodegeneration and cognition. DISCUSSION: Microglia are associated with AD pathology and cognition and may mediate relationships between subsequent steps in AD progression.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Microglia/metabolismo , Proteínas tau/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Disfunção Cognitiva/metabolismo , Progressão da Doença , Receptores de GABA/metabolismo
3.
PLoS One ; 18(11): e0291151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37956126

RESUMO

Stochastic population models are widely used to model phenomena in different areas such as cyber-physical systems, chemical kinetics, collective animal behaviour, and beyond. Quantitative analysis of stochastic population models easily becomes challenging due to the combinatorial number of possible states of the population. Moreover, while the modeller easily hypothesises the mechanistic aspects of the model, the quantitative parameters associated to these mechanistic transitions are difficult or impossible to measure directly. In this paper, we investigate how formal verification methods can aid parameter inference for population discrete-time Markov chains in a scenario where only a limited sample of population-level data measurements-sample distributions among terminal states-are available. We first discuss the parameter identifiability and uncertainty quantification in this setup, as well as how the existing techniques of formal parameter synthesis and Bayesian inference apply. Then, we propose and implement four different methods, three of which incorporate formal parameter synthesis as a pre-computation step. We empirically evaluate the performance of the proposed methods over four representative case studies. We find that our proposed methods incorporating formal parameter synthesis as a pre-computation step allow us to significantly enhance the accuracy, precision, and scalability of inference. Specifically, in the case of unidentifiable parameters, we accurately capture the subspace of parameters which is data-compliant at a desired confidence level.


Assuntos
Modelos Biológicos , Animais , Teorema de Bayes , Cadeias de Markov
4.
Front Neurol ; 14: 1174116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360347

RESUMO

Objective: To assess the demographics, neurologic manifestations, comorbidities, and treatment of patients with seronegative primary Sjögren's syndrome (pSS). Patients and methods: We conducted a retrospective chart review on patients with seronegative pSS evaluated by a neurologist at the University of Utah Health between January 2010 and October 2018. The diagnosis was based on characteristic symptoms, positive minor salivary gland biopsy according to the American-European Consensus Group 2002 criteria, and seronegative antibody status. Results: Of 45 patients who met the study criteria, 42 (93.3%) were Caucasian, and 38 (84.4%) were female. The patients' mean age at diagnosis was 47.8 ± 12.6 (range 13-71) years. Paresthesia, numbness and dizziness, and headache were noted in 40 (88.9%), 39 (86.7%), and 36 patients (80.0%), respectively. Thirty-four patients underwent brain magnetic resonance imaging. Of these, 18 (52.9%) showed scattered nonspecific periventricular and subcortical cerebral white matter T2/fluid-attenuated inversion recovery hyperintense foci. Twenty-nine patients (64.4%) presented to the neurology clinic prior to pSS diagnosis, and the median delay in diagnosis from the first neurology clinic visit was 5 (interquartile ranges 2.0-20.5) months. Migraine and depression were the most common comorbidities in 31 patients (68.9%). Thirty-six patients received at least one immunotherapy, and 39 were on at least one medication for neuropathic pain. Conclusion: Patients often display various nonspecific neurological symptoms. Clinicians should express a high degree of skepticism regarding seronegative pSS and consider minor salivary gland biopsy to avoid delaying diagnosis, as undertreatment can affect patients' quality of life.

5.
Am J Trop Med Hyg ; 109(1): 214-216, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37188346

RESUMO

Lower respiratory tract infections (LRTIs) are the leading cause of death in young children globally. Most of the global burden of mortality from LRTIs occurs in low-resource settings (LRSs), where obtaining and maintaining respiratory support devices such as commercial bubble continuous positive airway pressure (bCPAP) can be prohibitive. Low-cost bCPAP devices exist, such as the homemade WHO-style bCPAP design, but the safety of this design has been called into question. Based on our team's experience with homemade bCPAP, the side effects of the high pressures described in recent studies are not commonly encountered. Therefore, we sought feedback via an international survey about various complications including pneumothorax from practitioners in LRSs who use two forms of homemade bCPAP. In our qualitative survey, we did not find a convincing pattern in the recall of complications between commercial bCPAP and homemade bCPAP with narrow- or wide-bore expiratory limb in neonates or older children.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Infecções Respiratórias , Recém-Nascido , Criança , Humanos , Adolescente , Pré-Escolar , Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Resultado do Tratamento
6.
Int J Mol Sci ; 24(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175551

RESUMO

The anti-malaria drug Artesunate (ART) shows strong anti-cancer effects in vitro; however, it shows only marginal treatment results in clinical cancer studies. In this study, ART was tested in preclinical 3D cancer models of increasing complexity using clinically relevant peak plasma concentrations to obtain further information for translation into clinical use. ART reduced cell viability in HCT-116 and HT-29 derived cancer spheroids (p < 0.001). HCT-116 spheroids responded dose-dependently, while HT-29 spheroids were affected more strongly by ART than by cytostatics (p < 0.001). HCT-116 spheroids were chemo-sensitized by ART (p < 0.001). In patient-derived cancer spheroids (PDCS), ART led to inhibition of cell viability in 84.62% of the 39 samples tested, with a mean inhibitory effect of 13.87%. Viability reduction of ART was 2-fold weaker than cytostatic monotherapies (p = 0.028). Meanwhile, tumor-stimulation of up to 16.30% was observed in six (15.38%) PDCS-models. In 15 PDCS samples, ART modulated chemotherapies in combined testing, eight of which showed chemo-stimulation (maximum of 36.90%) and seven chemo-inhibition (up to 16.95%). These results demonstrate that ART's anti-cancer efficacy depends on the complexity of the tumor model used. This emphasizes that cancer treatment with ART should be evaluated before treatment of the individual patient to ensure its benefits and prevent unwanted effects.


Assuntos
Antimaláricos , Humanos , Artesunato/farmacologia , Artesunato/uso terapêutico , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Células HT29
7.
PLoS Comput Biol ; 18(9): e1010305, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36107824

RESUMO

Honeybees protect their colony against vertebrates by mass stinging and they coordinate their actions during this crucial event thanks to an alarm pheromone carried directly on the stinger, which is therefore released upon stinging. The pheromone then recruits nearby bees so that more and more bees participate in the defence. However, a quantitative understanding of how an individual bee adapts its stinging response during the course of an attack is still a challenge: Typically, only the group behaviour is effectively measurable in experiment; Further, linking the observed group behaviour with individual responses requires a probabilistic model enumerating a combinatorial number of possible group contexts during the defence; Finally, extracting the individual characteristics from group observations requires novel methods for parameter inference. We first experimentally observed the behaviour of groups of bees confronted with a fake predator inside an arena and quantified their defensive reaction by counting the number of stingers embedded in the dummy at the end of a trial. We propose a biologically plausible model of this phenomenon, which transparently links the choice of each individual bee to sting or not, to its group context at the time of the decision. Then, we propose an efficient method for inferring the parameters of the model from the experimental data. Finally, we use this methodology to investigate the effect of group size on stinging initiation and alarm pheromone recruitment. Our findings shed light on how the social context influences stinging behaviour, by quantifying how the alarm pheromone concentration level affects the decision of each bee to sting or not in a given group size. We show that recruitment is curbed as group size grows, thus suggesting that the presence of nestmates is integrated as a negative cue by individual bees. Moreover, the unique integration of exact and statistical methods provides a quantitative characterisation of uncertainty associated to each of the inferred parameters.


Assuntos
Abelhas , Comportamento Animal , Comportamento Social , Animais , Abelhas/fisiologia , Comportamento Animal/fisiologia , Feromônios/fisiologia
8.
Vaccines (Basel) ; 10(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35891222

RESUMO

While the COVID-19 pandemic has caused major educational disruptions, it has also catalyzed innovation in service-learning as a real-time response to pandemic-related problems. The limited number of qualified providers was primed to restrict SARS-CoV-2 vaccination efforts. Thus, New York State temporarily allowed healthcare professional trainees to vaccinate, enabling medical students to support an overwhelmed healthcare system and contribute to the public health crisis. Here, we describe a service-learning vaccination program directed towards underserved communities. A faculty-led curriculum prepared medical students to communicate with patients about COVID-19 vaccines and to administer intramuscular injections. Qualified students were deployed to public vaccination clinics located in under-served neighborhoods in collaboration with an established community partner. Throughout the program, 128 students worked at 103 local events, helping to administer 26,889 vaccine doses. Analysis of a retrospective survey administered to participants revealed the program taught fundamental clinical skills and was a transformative service-learning experience. As new virus variants emerge and nations battle recurrent waves of infection, the need for effective vaccination plans continues to grow. The program described here offers a novel framework that academic medical centers could adapt to increase vaccine access in their local community and provide students with a uniquely meaningful educational experience.

9.
J Environ Manage ; 316: 115040, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35594826

RESUMO

We co-designed an agent-based model of an Afroalpine grassland in Ethiopia that is experiencing unwanted shrub encroachment. The goal was to enable managers of a community conservation area to better understand the drivers of shrub encroachment and to test possible management actions for controlling shrubs. Due to limited site-specific data, we parameterized this model using insights from published literature, remote sensing, and expert opinion from scientists and local managers. We therefore sought to explore potential future scenarios rather than make highly accurate predictions, focusing on facilitating discussions and learning among the diverse co-management team. We evaluated three social-ecological scenarios with our model, examining: (1) the impact of changing precipitation regimes on vegetation, (2) whether changing the frequency of guassa grass harvests would improve the long-term sustainability of the grassland, and (3) whether the combination of grass harvest and shrub removal would affect shrub encroachment. We found that the model was highly sensitive to the amount of grass harvested each year for local use. Our results indicate that the guassa grass was more resilient than shrubs during persistent dry climatic conditions, whereas a reduction in only the early spring rains (known as the "belg") resulted in considerable loss of grass biomass. While our modeling results lacked the quantitative specificity desired by managers, participants in the collaborative modeling process learned new approaches to planning and management of the conservation area and expanded their knowledge of the ecological complexity of the system. Several participants used the model as a boundary object, interpreting it in ways that reinforced their cultural values and goals for the conservation area. Our work highlights the lack of detailed scientific knowledge of Afroalpine ecosystems, and urges managers to reconnect with traditional ecological management of the conservation area in their pursuit of shrub encroachment solutions. The decline or absence of the belg rains is becoming increasingly common in the Ethiopian highlands, and our results underscore the need for more widespread understanding of how this changing climatic regime impacts local environmental management. This work lays a foundation for social-ecological research to improve both understanding and management of these highly threatened ecosystems.


Assuntos
Pradaria , Análise de Sistemas , Ecossistema , Monitoramento Ambiental , Humanos , Poaceae , Estações do Ano
10.
Female Pelvic Med Reconstr Surg ; 28(6): e171-e178, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35420550

RESUMO

IMPORTANCE: Pessaries are an important conservative therapy for stress urinary incontinence (SUI), but few studies have comprehensively evaluated their utility. OBJECTIVE: The objective of this study is to evaluate the existing evidence on the efficacy and safety of pessaries for the treatment of SUI. STUDY DESIGN: We searched for the terms "stress urinary incontinence" and "pessar/y/ies/ium" in PubMed, Embase, and Cinhal on June 10, 2020. Studies that characterized subjective and/or objective data were included. Studies performed in pediatric populations, pregnancy, and use of pessaries not for SUI were excluded. Two reviewers independently screened and assessed data quality and risk of bias according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Ten studies, including 376 patients, were included. In terms of subjective outcomes, 76% of 72 patients reported feeling continent after pessary treatment compared with 0% of 86 patients surveyed before pessary use (P < 0.0001). Both Urinary Distress Inventory and Incontinence Impact Questionnaire scores decreased significantly by 46.7% (n = 155 baseline, n = 139 follow-up; P < 0.0001) and 67.8% (n = 139 baseline, n = 107 follow-up; P < 0.0001), respectively. Significant objective measures associated with pessary use included increased urethral closure pressure (n = 122; g = 0.56; 95% confidence interval [CI], -0.66 to 1.77; P < 0.049) and decreased pad weight (n = 129 baseline; n = 118 follow-up; g = -0.89; 95% CI, -1.986 to 0.19; P = 0.009). Adverse events significantly decreased at greater than 6 months follow-up compared with less than 6 months follow-up, including pain (31.5%, n = 29/92 vs 14.3%, n = 5/35; P = 0.0513) and discomfort (50%, n = 46/92 vs 29.3%, n = 12/41; P = 0.0268). CONCLUSIONS: Based on both subjective and objective measures, pessaries are an effective conservative treatment option for SUI. This supports pessary use, though larger studies with longer-term follow-up are warranted.


Assuntos
Incontinência Urinária por Estresse , Incontinência Urinária , Criança , Feminino , Humanos , Pessários/efeitos adversos , Inquéritos e Questionários , Uretra , Incontinência Urinária/terapia , Incontinência Urinária por Estresse/terapia
11.
Alzheimers Dement ; 18(2): 272-282, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34057284

RESUMO

INTRODUCTION: Positron emission tomography (PET) imaging for neurofibrillary tau allows investigation of the in vivo spatiotemporal progression of Alzheimer's disease (AD) pathology. We evaluated the suitability of 18 F-MK-6240 in a clinical sample and determined the relationships among 18 F-MK-6240 binding, age, cognition, and cerebrospinal fluid (CSF)-based AD biomarkers. METHODS: Participants (n = 101, 72 ± 9 years, 52% women) underwent amyloid PET, tau PET, structural T1-weighted magnetic resonance imaging, and neuropsychological evaluation. Twenty-one participants had lumbar puncture for CSF measurement of amyloid beta (Aß)42 , tau, and phosphorylated tau (p-tau). RESULTS: 18 F-MK-6240 recapitulated Braak staging and correlated with CSF tau and p-tau, normalized to Aß42 . 18 F-MK-6240 negatively correlated with age across Braak regions in amyloid-positive participants, consistent with greater tau pathology in earlier onset AD. Domain-specific, regional patterns of 18 F-MK-6240 binding were associated with reduced memory, executive, and language performance, but only in amyloid-positive participants. DISCUSSION: 18 F-MK-6240 can approximate Braak staging across the AD continuum and provide region-dependent insights into biomarker-based AD models.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Biomarcadores , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Feminino , Humanos , Isoquinolinas/metabolismo , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Proteínas tau/líquido cefalorraquidiano
12.
Glob Chang Biol ; 28(4): 1618-1629, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34755425

RESUMO

The alpine meadow ecosystem on the Qinghai-Tibetan Plateau (QTP) is very sensitive to warming and plays a key role in regulating global carbon (C) cycling. However, how warming affects the soil organic carbon (SOC) pool and related C inputs and outputs in alpine meadow ecosystems on the QTP remains unclear. Here, we combined two field experiments and a meta-analysis on field experiments to synthesize the responses of the SOC pool and related C cycling processes to warming in alpine meadow ecosystems on the QTP. We found that the SOC content of surface soil (0-10 cm) showed a minor response to warming, but plant respiration was accelerated by warming. In addition, the warming effect on SOC was not correlated with experimental and environmental variables, such as the method, magnitude and duration of warming, initial SOC content, mean annual temperature, and mean annual precipitation. We conclude that the surface SOC content is resistant to climate warming in alpine meadow ecosystems on the QTP.


Assuntos
Carbono , Solo , Carbono/análise , Ecossistema , Pradaria , Tibet
13.
Front Public Health ; 9: 556648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732671

RESUMO

Sickness allowance is paid for short-term sickness absence and is thus an indicator of temporary ill health, but it is also associated with a heightened risk of receiving disability pension. Using event history analysis, we examined the long-term risk for disability pension receipt after first observed receipt of medically certified sickness allowance in each single year after sickness allowance was first recorded. Utilizing longitudinal data from the Finnish population register, covering the period 1989-2010, we observed 110,675 individuals aged 16-40 years at baseline. Using discrete-time hazard models, we estimated how the first observed receipt of sickness allowance was related to the risk of receiving disability pension, with an average follow-up time of 20.6 years. In this population, about 40 percent received sickness allowance and 10 percent received disability pension. In the first years after sickness allowance receipt, there was a substantial difference between long-term and short-term sickness allowance recipients in the hazard of becoming a disability pensioner. This difference levelled out over time, but even 20 years after the first observed sickness allowance receipt, the hazard of disability retirement was more than 15 times higher than that of non-recipients of sickness allowance. Patterns were similar for men and women. First observed receipt of sickness allowance is a powerful predictor for disability pension receipt, also in the very distant future. Thus, it can be used to monitor people with heightened risk of becoming more permanently ill and falling outside the labour market.


Assuntos
Pessoas com Deficiência , Licença Médica , Adolescente , Adulto , Feminino , Finlândia/epidemiologia , Seguimentos , Humanos , Masculino , Pensões , Adulto Jovem
14.
J Alzheimers Dis ; 80(3): 1051-1065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33646153

RESUMO

BACKGROUND: Olfactory impairment is evident in Alzheimer's disease (AD); however, its precise relationships with clinical biomarker measures of tau pathology and neuroinflammation are not well understood. OBJECTIVE: To determine if odor identification performance measured with the University of Pennsylvania Smell Identification Test (UPSIT) is related to in vivo measures of tau pathology and neuroinflammation. METHODS: Cognitively normal and cognitively impaired participants were selected from an established research cohort of adults aged 50 and older who underwent neuropsychological testing, brain MRI, and amyloid PET. Fifty-four participants were administered the UPSIT. Forty-one underwent 18F-MK-6240 PET (measuring tau pathology) and fifty-three underwent 11C-PBR28 PET (measuring TSPO, present in activated microglia). Twenty-three participants had lumbar puncture to measure CSF concentrations of total tau (t-tau), phosphorylated tau (p-tau), and amyloid-ß (Aß42). RESULTS: Low UPSIT performance was associated with greater18F-MK-6240 binding in medial temporal cortex, hippocampus, middle/inferior temporal gyri, inferior parietal cortex, and posterior cingulate cortex (p < 0.05). Similar relationships were seen for 11C-PBR28. These relationships were primarily driven by amyloid-positive participants. Lower UPSIT performance was associated with greater CSF concentrations of t-tau and p-tau (p < 0.05). Amyloid status and cognitive status exhibited independent effects on UPSIT performance (p < 0.01). CONCLUSION: Olfactory identification deficits are related to extent of tau pathology and neuroinflammation, particularly in those with amyloid pathophysiology. The independent association of amyloid-positivity and cognitive impairment with odor identification suggests that low UPSIT performance may be a marker for AD pathophysiology in cognitive normal individuals, although impaired odor identification is associated with both AD and non-AD related neurodegeneration.NCT Registration Numbers: NCT03373604; NCT02831283.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Transtornos do Olfato/etiologia , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/metabolismo , Transtornos do Olfato/patologia , Tomografia por Emissão de Pósitrons
15.
Chembiochem ; 22(11): 1925-1931, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33554446

RESUMO

We report the application of a highly versatile and engineerable novel sensor platform to monitor biologically significant and toxic metal ions in live human Caco-2 enterocytes. The extended conjugation between the fluorescent porphyrin core and metal ions through aromatic phenylphosphonic acid tethers generates a unique turn off and turn on fluorescence and, in addition, shifts in absorption and emission spectra for zinc, cobalt, cadmium and mercury. The reported fluorescent probes p-H8 TPPA and m-H8 TPPA can monitor a wide range of metal ion concentrations via fluorescence titration and also via fluorescence decay curves. Cu- and Zn-induced turn off fluorescence can be differentially reversed by the addition of common chelators. Both p-H8 TPPA and m-H8 TPPA readily pass the mammalian cellular membrane due to their amphipathic character as confirmed by confocal microscopic imaging of living enterocytes.


Assuntos
Complexos de Coordenação/química , Enterócitos/química , Corantes Fluorescentes/química , Metais Pesados/análise , Organofosfonatos/química , Porfirinas/química , Células CACO-2 , Fluorescência , Humanos
16.
Sci Rep ; 11(1): 2631, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514788

RESUMO

The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.


Assuntos
Músculo Esquelético/diagnóstico por imagem , Miografia , Doença de Parkinson/diagnóstico , Tremor/diagnóstico , Aceleração , Idoso , Braço/diagnóstico por imagem , Braço/fisiopatologia , Feminino , Antebraço/diagnóstico por imagem , Antebraço/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Tremor/diagnóstico por imagem , Tremor/fisiopatologia
18.
J Neurophysiol ; 124(4): 1183-1197, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902350

RESUMO

Previously, an essential tremor-like phenotype has been noted in animals with a global knockout of the GABAAα1 subunit. Given the hypothesized role of the cerebellum in tremor, including essential tremor, we used transgenic mice to selectively knock out the GABAAα1 subunit from cerebellar Purkinje cells. We examined the resulting phenotype regarding impacts on inhibitory postsynaptic currents, survival rates, gross motor abilities, and expression of tremor. Purkinje cell specific knockout of the GABAAα1 subunit abolished all GABAA-mediated inhibition in Purkinje cells, while leaving GABAA-mediated inhibition to cerebellar molecular layer interneurons intact. Selective loss of GABAAα1 from Purkinje cells did not produce deficits on the accelerating rotarod, nor did it result in decreased survival rates. However, a tremor phenotype was apparent, regardless of sex or background strain. This tremor mimicked the tremor seen in animals with a global knockout of the GABAAα1 subunit, and, like essential tremor in patients, was responsive to ethanol. These findings indicate that reduced inhibition to Purkinje cells is sufficient to induce a tremor phenotype, highlighting the importance of the cerebellum, inhibition, and Purkinje cells in tremor.NEW & NOTEWORTHY Animals with a global knockout of the GABAAα1 subunit show a tremor phenotype reminiscent of essential tremor. Here we show that selective knockout of GABAAα1 from Purkinje cells is sufficient to produce a tremor phenotype, although this tremor is less severe than seen in animals with a global knockout. These findings illustrate that the cerebellum can play a key role in the genesis of the observed tremor phenotype.


Assuntos
Células de Purkinje/metabolismo , Receptores de GABA-A/genética , Tremor/genética , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Células de Purkinje/fisiologia , Receptores de GABA-A/metabolismo , Tremor/metabolismo , Tremor/fisiopatologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-32404428

RESUMO

OBJECTIVE: To characterize patients with neurosarcoidosis within the University of Utah healthcare system, including demographics, clinical characteristics, treatment, and long-term outcomes. METHODS: We describe the clinical features and outcomes of patients with neurosarcoidosis within the University of Utah healthcare system (a large referral center for 10% of the continental United States by land mass). Patients were selected who met the following criteria: (1) at least one International Classification of Diseases Clinical Modification, 9th revision code 135 or International Classification of Diseases Clinical Modification, 10th revision code D86* (sarcoidosis) and (2) at least one outpatient visit with a University of Utah clinician in the Neurology Department within the University of Utah electronic health record. RESULTS: We identified 56 patients meeting the study criteria. Thirty-five patients (63%) were women, and most patients (84%) were white. Twelve patients (22%) met the criteria for definite neurosarcoidosis, 36 patients (64%) were diagnosed with probable neurosarcoidosis, and 8 patients (14%) were diagnosed with possible neurosarcoidosis. A total of 8 medications were used for the treatment of neurosarcoidosis. Prednisone was the first-line treatment in 51 patients (91%). Infliximab was the most effective therapy, with 87% of patients remaining stable or improving on infliximab. Treatment response for methotrexate and azathioprine was mixed, and mycophenolate mofetil and rituximab were the least effective treatments in this cohort. CONCLUSIONS: This is a comprehensive characterization of neurosarcoidosis within a single healthcare system at the University of Utah that reports long-term response to treatment and outcomes of patients with neurosarcoidosis. Our results suggest the use of infliximab as a first-line therapy for neurosarcoidosis.


Assuntos
Antirreumáticos/uso terapêutico , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/epidemiologia , Glucocorticoides/uso terapêutico , Fatores Imunológicos/uso terapêutico , Infliximab/uso terapêutico , Sarcoidose/tratamento farmacológico , Sarcoidose/epidemiologia , Centros Médicos Acadêmicos/estatística & dados numéricos , Adulto , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/etnologia , Feminino , Serviços de Saúde/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sarcoidose/diagnóstico , Sarcoidose/etnologia , Utah/epidemiologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-32273482

RESUMO

OBJECTIVE: To provide first real-world experience on patients with MS treated with the B cell-depleting antibody ocrelizumab. METHODS: We retrospectively collected data of patients who had received at least 1 treatment cycle (2 infusions) of ocrelizumab at 3 large neurology centers. Patients' characteristics including premedication, clinical disease course, and documented side effects were analyzed. RESULTS: We could identify 210 patients (125 women, mean age ± SD, 42.1 ± 11.4 years) who had received ocrelizumab with a mean disease duration of 7.3 years and a median Expanded Disability Status Scale score of 3.75 (interquartile range 2.5-5.5; range 0-8). Twenty-six percent of these patients had a primary progressive MS (PPMS), whereas 74% had a relapsing-remitting (RRMS) or active secondary progressive (aSPMS) disease course. Twenty-four percent of all patients were treatment naive, whereas 76% had received immune therapies before. After ocrelizumab initiation (median follow-up was 200 days, range 30-1,674 days), 13% of patients with RRMS/aSPMS experienced a relapse (accounting for an annualized relapse rate of 0.17, 95% CI 0.10-0.24), and 5% of all patients with MS experienced a 12-week confirmed disability progression. Treatment was generally well tolerated, albeit only short-term side effects were recorded, including direct infusion-related reactions and mild infections. CONCLUSIONS: We provide class IV evidence that treatment with ocrelizumab can stabilize naive and pretreated patients, indicating that ocrelizumab is an option following potent MS drugs such as natalizumab and fingolimod. Further studies are warranted to confirm these findings and to reveal safety concerns in the longer-term follow-up. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with MS, ocrelizumab can stabilize both treatment-naive and previously treated patients.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Fatores Imunológicos/farmacologia , Esclerose Múltipla/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Progressão da Doença , Feminino , Seguimentos , Humanos , Fatores Imunológicos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Índice de Gravidade de Doença
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