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1.
Ann Neurol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860478

RESUMO

OBJECTIVE: To explore the clinical progression of the brain-/body-first categories within Lewy body disease (LBD): Parkinson's disease (PD), dementia with Lewy bodies (DLB), and PD dementia. METHODS: We used of the Rochester Epidemiology Project to establish a population-based cohort of clinically diagnosed LBD. We used two definitions for differentiating between brain- and body-first LBD: a previously hypothesized body-first presentation in patients with rapid eye movement sleep behavior onset before motor symptoms onset; and an expanded definition of body-first LBD when a patient had at least 2 premotor symptoms between constipation, erectile dysfunction, rapid eye movement sleep behavior, anosmia, or neurogenic bladder. RESULTS: Brain-first patients were more likely to be diagnosed with PD (RR = 1.43, p = 0.003), whereas body-first patients were more likely to be diagnosed with DLB (RR = 3.15, p < 0.001). Under the expanded definition, there was no difference in LBD diagnosis between brain-first and body-first patients (PD: RR = 1.03, p = 0.10; DLB: RR = 0.88, p = 0.58) There were no patterns between brain- or body-first presentation, PD dementia under either definition (original: p = 0.09, expanded: p = 0.97), and no significant difference in motor symptoms between brain-first and body-first. INTERPRETATION: Our findings do not support the dichotomous classification of body-first and brain-first LBD with the currently proposed definition. Biological exposures resulting in PD and DLB are unlikely to converge on a binary classification of top-down or bottom-up synuclein pathology. ANN NEUROL 2024.

2.
Proc Natl Acad Sci U S A ; 119(43): e2208672119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36256821

RESUMO

Recent studies have identified serotonylation of glutamine-5 on histone H3 (H3Q5ser) as a novel posttranslational modification (PTM) associated with active transcription. While H3Q5ser is known to be installed by tissue transglutaminase 2 (TGM2), the substrate characteristics affecting deposition of the mark, at the level of both chromatin and individual nucleosomes, remain poorly understood. Here, we show that histone serotonylation is excluded from constitutive heterochromatic regions in mammalian cells. Biochemical studies reveal that the formation of higher-order chromatin structures associated with heterochromatin impose a steric barrier that is refractory to TGM2-mediated histone monoaminylation. A series of structure-activity relationship studies, including the use of DNA-barcoded nucleosome libraries, shows that steric hindrance also steers TGM2 activity at the nucleosome level, restricting monoaminylation to accessible sites within histone tails. Collectively, our data indicate that the activity of TGM2 on chromatin is dictated by substrate accessibility rather than by primary sequence determinants or by the existence of preexisting PTMs, as is the case for many other histone-modifying enzymes.


Assuntos
Histonas , Nucleossomos , Animais , Histonas/genética , Histonas/química , Glutamina , Heterocromatina , Proteína 2 Glutamina gama-Glutamiltransferase , Cromatina/genética , DNA/química , Mamíferos
3.
Clin Infect Dis ; 78(1): 90-93, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37585653

RESUMO

In a cross-sectional analysis of 354 Ugandan children (age 12-48 months) infected with Schistosoma mansoni, we assessed relationships between infection intensity and nutritional morbidities. Higher intensity was associated with an increased risk for anemia (RR = 1.05, 95% confidence interval [CI] 1.01-1.10) yet not associated with risk for underweight, stunting, or wasting.


Assuntos
Anemia , Esquistossomose mansoni , Criança , Animais , Humanos , Pré-Escolar , Lactente , Esquistossomose mansoni/complicações , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Estado Nutricional , Estudos Transversais , Prevalência , Schistosoma mansoni , Anemia/epidemiologia , Anemia/etiologia
4.
J Vasc Surg ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38552883

RESUMO

OBJECTIVE: To present a single-center prospective study of 126 consecutively treated patients who underwent endovascular repair of a thoracoabdominal aortic aneurysm with the physician-modified, nonanatomic-based Unitary Manifold (UM) device. METHODS: Data were collected from 126 consecutive all-comer patients treated with the physician-modified, nonanatomic-based UM from 2015 to 2023. Treatment was performed at a single center by a single physician under a Physician Sponsored Investigation Exemption G140207. RESULTS: The UM was indicated for repair of all Crawford extents including juxtarenal, pararenal, and short-neck infrarenal aneurysms (<10 mm) in 126 consecutive patients. Patients were not excluded from the study based on presentation, extent of aneurysm or dissection, or history of a spinal cord event. Patients with a thoracoabdominal aortic aneurysm were categorized by Crawford classification: types I and V (3.3%, n = 4), type II (3.3%, n = 4), type III (1%, n = 1), and type IV (93.3%, n = 117). The type IV classification patients were further categorized with 33 (28.2%) true type IV, 68 (58.1%) pararenal or infrarenal, and 16 (13.7%) with dissection. Technical success was 99.2% (n = 125). The most common major adverse event within both 30 days and 365 days of all patients was respiratory failure (11.9%, n = 15, and 13.5%, n = 17, respectively). One patient (0.8%) experienced persistent paraplegia at 365 days. Reintervention for patients at 365 days was 5.6% (n = 7). Of the 444 branches stented, the primary patency rate was remarkably high as only three patients (2.4%) required reintervention due to loss of limb patency within 365 days. Aneurysm enlargement (≥5 mm) occurred in 1.6% (n = 2) patients, and no patients experienced aneurysm rupture. No patients underwent conversion to open repair. The aneurysm-related mortality at 365 days for all patients was 4.0% (n = 5), whereas all-cause mortality was 16.7% (n = 21). Physician-modified endograft device integrity failure was not observed in any patient. CONCLUSIONS: The UM device demonstrated remarkable technical surgical success, treatment success, and device patency rates with very reasonable major adverse events and reintervention rates. This study is the most representative example of the general population in comparison with other studies of off-the-shelf devices, with 126 consecutive all-comer patients with diverse pathologies.

5.
Am J Med Genet A ; : e63638, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38779990

RESUMO

Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty evaluations performed at the Massachusetts General Hospital (MGH) Myhre Syndrome Clinic (2016-2023) and by collaborating specialists have facilitated deep phenotyping, genotyping and natural history analysis. Of 47 patients (four previously reported), most (81%) patients returned to MGH at least once. For patients followed for at least 5 years, symptom progression was observed in all. 55% were female and 9% were older than 18 years at diagnosis. Pathogenic variants in SMAD4 involved protein residues p.Ile500Val (49%), p.Ile500Thr (11%), p.Ile500Leu (2%), and p.Arg496Cys (38%). Individuals with the SMAD4 variant p.Arg496Cys were less likely to have hearing loss, growth restriction, and aortic hypoplasia than the other variant groups. Those with the p.Ile500Thr variant had moderate/severe aortic hypoplasia in three patients (60%), however, the small number (n = 5) prevented statistical comparison with the other variants. Two deaths reported in this cohort involved complex cardiovascular disease and airway stenosis, respectively. We provide a foundation for ongoing natural history studies and emphasize the need for evidence-based guidelines in anticipation of disease-specific therapies.

6.
Chemphyschem ; : e202400360, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780298

RESUMO

Adsorption in nanoporous materials is one strategy that can be used to store hydrogen at conditions of temperature and pressure that are economically viable. Adsorption capacity of nanoporous materials depends on surface area which can be enhanced by incorporating a hierarchical pore structure. We report grand canonical Monte Carlo (GCMC) simulation results on the adsorption of hydrogen in hierarchical models of silicalite that incorporate 4 nm wide mesopores in addition to the 0.5 nm wide micropores at 298 K, using different force fields to model hydrogen. Our results suggest that incorporating mesopores in silicalite can enhance adsorption by at least 20 % if electrostatic interactions are not included and up to 100 % otherwise. Incorporating electrostatic interactions results in higher adsorption by close to 100 % at lower pressures for hierarchical silicalite whereas for unmodified silicalite, it is less significant at all pressures. Hydroxylating the mesopore surface in hierarchical silicalite results in an enhancement in adsorption at pressures below 1 atm and suppression by up to 20 % at higher pressures. Temperature dependence at selected pressures exhibits expected decrease in adsorption amounts at higher temperatures. These findings can be useful in the engineering, selection, and optimization of nanoporous materials for hydrogen storage.

7.
Future Oncol ; 20(9): 547-561, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38197386

RESUMO

Aims: To characterize Black, Indigenous and People of Color (BIPOC) adolescent and young adult (AYA) cancer patients' experiences of patient engagement in AYA oncology and derive best practices that are co-developed by BIPOC AYAs and oncology professionals. Materials & methods: Following a previous call to action from AYA oncology professionals, a panel of experts composed exclusively of BIPOC AYA cancer patients (n = 32) participated in an electronic Delphi study. Results: Emergent themes described BIPOC AYA cancer patients' direct experiences and consensus opinion on recommendations to advance antiracist patient engagement from BIPOC AYA cancer patients and oncology professionals. Conclusion: The findings reveal high-priority practices across all phases of research and are instructional for advancing health equity.


Assuntos
Neoplasias , Participação do Paciente , Humanos , Adolescente , Adulto Jovem , Técnica Delphi , Oncologia , Neoplasias/terapia
8.
S D Med ; 77(5): 207-210, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39012773

RESUMO

A Caucasian male in his 60s presented with acute onset of dizziness, dysarthria, and gait ataxia. Upon extensive workup, positive findings were cerebrospinal fluid (CSF) showing lymphocytic pleocytosis with oligoclonal bands, positive celiac disease autoantibodies in blood, a duodenal biopsy indicating lymphocytic infiltration, and positive anti-mGluR1 antibody titers in CSF. The patient was started on a strict gluten-free diet and intravenous immunoglobulin therapy for 5 days and showed mild consecutive improvements each day of treatment. He was discharged after 22 days, and was encouraged to continue gluten adherence, physical and speech therapy, and follow up with neuroimmunology. This report demonstrates that autoimmune encephalitis due to anti-mGluR1antibodies and gluten ataxia are both immune-mediated disorders that should be considered in acute cerebellar ataxia cases. By broadening the differential diagnosis and a comprehensive CSF analysis, identification of gluten ataxia and autoimmune encephalitis were beneficial in the management of this particular patient.


Assuntos
Doença Celíaca , Ataxia Cerebelar , Encefalite , Humanos , Masculino , Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/etiologia , Encefalite/diagnóstico , Diagnóstico Diferencial , Doença Celíaca/diagnóstico , Doença Celíaca/complicações , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/complicações , Receptores de Glutamato Metabotrópico , Dieta Livre de Glúten , Autoanticorpos/sangue , Pessoa de Meia-Idade , Glutens/efeitos adversos , Doenças Autoimunes do Sistema Nervoso/diagnóstico
9.
S D Med ; 77(7): 316-319, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39013187

RESUMO

We report a Native American male in his 50s with a complex medical history including alcohol use disorder and seizure disorder who presented with complaints of generalized weakness and multiple falls. The patient was admitted for altered mental status, community acquired pneumonia, sepsis, and bacteremia. On hospital day 23, the patient reported a sudden onset of sensation of food stuck in his upper chest. Brain MRI confirmed osmotic demyelination syndrome (ODS) within the central pons. Further workup revealed this finding was likely due to malnutrition, alcoholism, hypoalbuminemia, and vitamin B6 deficiency. However, the patient presented with normonatremia throughout his entire hospital stay. After acute onset of ODS, the patient was transferred to the ICU where he continued to decline. After 68 days from initial presentation, the patient died in hospice care from myelinolysis complications. This case demonstrates a case of ODS of the central pons in a patient with normonatremia, hypoalbuminemia, and severe vitamin B6 deficiency.


Assuntos
Alcoolismo , Mielinólise Central da Ponte , Deficiência de Vitamina B 6 , Humanos , Masculino , Mielinólise Central da Ponte/etiologia , Mielinólise Central da Ponte/diagnóstico , Alcoolismo/complicações , Pessoa de Meia-Idade , Deficiência de Vitamina B 6/complicações , Evolução Fatal , Imageamento por Ressonância Magnética , Sódio/sangue
10.
Glia ; 71(3): 633-647, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36382566

RESUMO

Oligodendrocyte (OL) damage and death are prominent features of multiple sclerosis (MS) pathology, yet mechanisms contributing to OL loss are incompletely understood. Dysfunctional RNA binding proteins (RBPs), hallmarked by nucleocytoplasmic mislocalization and altered expression, have been shown to result in cell loss in neurologic diseases, including in MS. Since we previously observed that the RBP heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) was dysfunctional in neurons in MS, we hypothesized that it might also contribute to OL pathology in MS and relevant models. We discovered that hnRNP A1 dysfunction is characteristic of OLs in MS brains. These findings were recapitulated in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS, where hnRNP A1 dysfunction was characteristic of OLs, including oligodendrocyte precursor cells and mature OLs in which hnRNP A1 dysfunction correlated with demyelination. We also found that hnRNP A1 dysfunction was induced by IFNγ, indicating that inflammation influences hnRNP A1 function. To fully understand the effects of hnRNP A1 dysfunction on OLs, we performed siRNA knockdown of hnRNP A1, followed by RNA sequencing. RNA sequencing detected over 4000 differentially expressed transcripts revealing alterations to RNA metabolism, cell morphology, and programmed cell death pathways. We confirmed that hnRNP A1 knockdown was detrimental to OLs and induced apoptosis and necroptosis. Together, these data demonstrate a critical role for hnRNP A1 in proper OL functioning and survival and suggest a potential mechanism of OL damage and death in MS that involves hnRNP A1 dysfunction.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Camundongos , Ribonucleoproteína Nuclear Heterogênea A1/genética , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Esclerose Múltipla/patologia , Proteínas de Ligação a RNA/metabolismo , RNA Interferente Pequeno
11.
Stroke ; 54(6): 1531-1537, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37139816

RESUMO

BACKGROUND: Adult hypertension is a well-established risk factor for stroke in young adults (aged <55 years), and the effects are even more deleterious than at an older age. However, data are limited regarding the association between adolescent hypertension and the risk of stroke in young adulthood. METHODS: A nationwide, retrospective cohort study of adolescents (aged 16-19 years) who were medically evaluated before compulsory military service in Israel during 1985 to 2013. For each candidate for service, hypertension was designated after constructed screening, and the diagnosis was confirmed through a comprehensive workup process. The primary outcome was ischemic and hemorrhagic stroke incidence as registered at the national stroke registry. Cox proportional-hazards models were used. We conducted sensitivity analyses by excluding people with a diabetes diagnosis at adolescence or a new diabetes diagnosis during the follow-up period, analysis of adolescents with overweight, and adolescents with baseline unimpaired health status. RESULTS: The final sample included 1 900 384 adolescents (58% men; median age, 17.3 years). In total, 1474 (0.08%) incidences of stroke (1236 [84%] ischemic) were recorded, at a median age of 43 (interquartile range, 38-47) years. Of these, 18 (0.35%) occurred among the 5221 people with a history of adolescent hypertension. The latter population had a hazard ratio of 2.4 (95% CI, 1.5-3.9) for incident stroke after adjustment for body mass index and baseline sociodemographic factors. Further adjustment for diabetes status yielded a hazard ratio of 2.1 (1.3-3.5). We found similar results when the outcome was ischemic stroke with a hazard ratio of 2.0 (1.2-3.5). Sensitivity analyses for overall stroke, and ischemic stroke only, yielded consistent findings. CONCLUSIONS: Adolescent hypertension is associated with an increased risk of stroke, particularly ischemic stroke, in young adulthood.


Assuntos
Diabetes Mellitus , Hipertensão , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Adulto Jovem , Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Hipertensão/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Incidência
12.
J Phys Chem A ; 127(30): 6227-6240, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37478410

RESUMO

UV photofragment spectroscopy and IR-UV double resonance methods are used to determine the structure and spectroscopic responses of a three-dimensional [2.2.2]-benzocryptand cage to the incorporation of a single K+ or Ba2+ imbedded inside it (labeled as K+-BzCrypt, Ba2+-BzCrypt). We studied the isolated ion-cryptand complex under cryo-cooled conditions, brought into the gas phase by nano-electrospray ionization. Incorporation of a phenyl ring in place of the central ethyl group in one of the three N-CH2-CH2-O-CH2-CH2-O-CH2-CH2-N chains provides a UV chromophore whose S0-S1 transition we probe. K+-BzCrypt and Ba2+-BzCrypt have their S0-S1 origin transitions at 35,925 and 36,446 cm-1, respectively, blue-shifted by 174 and 695 cm-1 from that of 1,2-dimethoxybenzene. These origins are used to excite a single conformation of each complex selectively and record their IR spectra using IR-UV dip spectroscopy. The alkyl CH stretch region (2800-3000 cm-1) is surprisingly sensitive to the presence and nature of the encapsulated ion. We carried out an exhaustive conformational search of cage conformations for K+-BzCrypt and Ba2+-BzCrypt, identifying two conformations (A and B) that lie below all others in energy. We extend our local mode anharmonic model of the CH stretch region to these strongly bound ion-cage complexes to predict conformation-specific alkyl CH stretch spectra, obtaining quantitative agreement with experiment for conformer A, the gas-phase global minimum. The large electrostatic effect of the charge on the O- and N-lone pairs affects the local mode frequencies of the CH2 groups adjacent to these atoms. The localized CH2 scissors modes are pushed up in frequency by the adjacent O/N-atoms so that their overtones have little effect on the alkyl CH stretch region. However, the localized CH2 wags are nearly degenerate and strongly coupled to one another, producing an array of delocalized wag normal modes, whose highest frequency members reach up above 1400 cm-1. As such, their overtones mix significantly with the CH stretch modes, most notably involving the CH2 symmetric stretch fundamentals of the central ethyl groups in the all-alkyl chains and the CH stretches adjacent to the N-atoms and antiperiplanar to the nitrogen lone pair.

13.
Ear Hear ; 44(6): 1311-1321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37226299

RESUMO

OBJECTIVES: Preschool programs provide essential preventive services, such as hearing screening, but in rural regions, limited access to specialists and loss to follow-up compound rural health disparities. We conducted a parallel-arm cluster-randomized controlled trial to evaluate telemedicine specialty referral for preschool hearing screening. The goal of this trial was to improve timely identification and treatment of early childhood infection-related hearing loss, a preventable condition with lifelong implications. We hypothesized that telemedicine specialty referral would improve time to follow-up and the number of children receiving follow-up compared with the standard primary care referral. DESIGN: We conducted a cluster-randomized controlled trial in K-12 schools in 15 communities over two academic years. Community randomization occurred within four strata using location and school size. In the second academic year (2018-2019), an ancillary trial was performed in the 14 communities that had preschools to compare telemedicine specialty referral (intervention) to standard primary care referral (comparison) for preschool hearing screening. Randomization of communities from the main trial was used for this ancillary trial. All children enrolled in preschool were eligible. Masking was not possible because of timing in the second year of the main trial, but referral assignment was not openly disclosed. Study team members and school staff were masked throughout data collection, and statisticians were blinded to allocation during analysis. Preschool screening occurred once, and children who were referred for possible hearing loss or ear disease were monitored for follow-up for 9 months from the screening date. The primary outcome was time to ear/hearing-related follow-up from the date of screening. The secondary outcome was any ear/hearing follow-up from screening to 9 months. Analyses were conducted using an intention-to-treat approach. RESULTS: A total of 153 children were screened between September 2018 and March 2019. Of the 14 communities, 8 were assigned to the telemedicine specialty referral pathway (90 children), and 6 to the standard primary care referral pathway (63 children). Seventy-one children (46.4%) were referred for follow-up: 39 (43.3%) in the telemedicine specialty referral communities and 32 (50.8%) in the standard primary care referral communities. Of children referred, 30 (76.9%) children in telemedicine specialty referral communities and 16 (50.0%) children in standard primary care referral communities received follow-up within 9 months (Risk Ratio = 1.57; 95% confidence interval [CI], 1.22 to 2.01). Among children who received follow-up, median time to follow-up was 28 days (interquartile range [IQR]: 15 to 71) in telemedicine specialty referral communities compared with 85 days (IQR: 26 to 129) in standard primary care referral communities. Mean time to follow-up for all referred children was 4.5 (event time ratio = 4.5; 95% CI, 1.8 to 11.4; p = 0.045) times faster in telemedicine specialty referral communities compared with standard primary care referral communities in the 9-month follow-up time frame. CONCLUSIONS: Telemedicine specialty referral significantly improved follow-up and reduced time to follow-up after preschool hearing screening in rural Alaska. Telemedicine referrals could extend to other preventive school-based services to improve access to specialty care for rural preschool children.


Assuntos
Surdez , Perda Auditiva , Telemedicina , Humanos , Pré-Escolar , Alaska , Perda Auditiva/diagnóstico , Serviços de Saúde Escolar , Encaminhamento e Consulta
14.
Ear Hear ; 44(5): 1240-1250, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287104

RESUMO

OBJECTIVES: Childhood hearing loss has well-known lifelong consequences. Certain rural populations are at higher risk for infection-related hearing loss. For Alaska Native children, historical data on hearing loss prevalence suggest a higher burden of infection-related hearing loss, but updated prevalence data are urgently needed in this high-risk population. DESIGN: Hearing data were collected as part of two school-based cluster-randomized trials in 15 communities in rural northwest Alaska over two academic years (2017-2019). All enrolled children from preschool to 12th grade were eligible. Pure-tone thresholds were obtained using standard audiometry and conditioned play when indicated. The analysis included the first available audiometric assessment for each child (n = 1634 participants, 3 to 21 years), except for the high-frequency analysis, which was limited to year 2 when higher frequencies were collected. Multiple imputation was used to quantify the prevalence of hearing loss in younger children, where missing data were more frequent due to the need for behavioral responses. Hearing loss in either ear was evaluated using both the former World Health Organization (WHO) definition (pure-tone average [PTA] > 25 dB) and the new WHO definition (PTA ≥ 20 dB), which was published after the study. Analyses with the new definition were limited to children 7 years and older due to incomplete data obtained on younger children at lower thresholds. RESULTS: The overall prevalence of hearing loss (PTA > 25 dB; 0.5, 1, 2, 4 kHz) was 10.5% (95% confidence interval [CI], 8.9 to 12.1). Hearing loss was predominately mild (PTA >25 to 40 dB; 8.9%, 95% CI, 7.4 to 10.5). The prevalence of unilateral hearing loss was 7.7% (95% CI, 6.3 to 9.0). Conductive hearing loss (air-bone gap of ≥ 10 dB) was the most common hearing loss type (9.1%, 95% CI, 7.6 to 10.7). Stratified by age, hearing loss (PTA >25 dB) was more common in children 3 to 6 years (14.9%, 95% CI, 11.4 to 18.5) compared to children 7 years and older (8.7%, 95% CI, 7.1 to 10.4). In children 7 years and older, the new WHO definition increased the prevalence of hearing loss to 23.4% (95% CI, 21.0 to 25.8) compared to the former definition (8.7%, 95% CI, 7.1 to 10.4). Middle ear disease prevalence was 17.6% (95% CI, 15.7 to 19.4) and was higher in younger children (23.6%, 95% CI, 19.7 to 27.6) compared to older children (15.2%, 95% CI, 13.2 to 17.3). High-frequency hearing loss (4, 6, 8kHz) was present in 20.5% (95% CI, 18.4 to 22.7 [PTA >25 dB]) of all children and 22.8% (95% CI, 20.3 to 25.3 [PTA >25 dB]) and 29.7% (95% CI, 27.0 to 32.4 [PTA ≥ 20 dB]) of children 7 years and older (limited to year 2). CONCLUSIONS: This analysis represents the first prevalence study on childhood hearing loss in Alaska in over 60 years and is the largest cohort with hearing data ever collected in rural Alaska. Our results highlight that hearing loss continues to be common in rural Alaska Native children, with middle ear disease more prevalent in younger children and high-frequency hearing loss more prevalent with increasing age. Prevention efforts may benefit from managing hearing loss type by age. Lastly, continued research is needed on the impact of the new WHO definition of hearing loss on field studies.


Assuntos
Surdez , Perda Auditiva de Alta Frequência , Criança , Humanos , Pré-Escolar , Adolescente , Alaska/epidemiologia , Prevalência , População Rural , Audiometria de Tons Puros/métodos
15.
Ear Hear ; 44(4): 877-893, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36907833

RESUMO

OBJECTIVES: Diagnostic accuracy was evaluated for various screening tools, including mobile health (mHealth) pure-tone screening, tympanometry, distortion product otoacoustic emissions (DPOAE), and inclusion of high frequencies to determine the most accurate screening protocol for identifying children with hearing loss in rural Alaska where the prevalence of middle ear disease is high. DESIGN: Hearing screening data were collected as part of two cluster randomized trials conducted in 15 communities in rural northwest Alaska. All children enrolled in school from preschool to 12th grade were eligible. Analysis was limited to data collected 2018 to 2019 (n = 1449), when both trials were running and measurement of high frequencies were included in the protocols. Analyses included estimates of diagnostic accuracy for each screening tool, as well as exploring performance by age and grade. Multiple imputation was used to assess diagnostic accuracy in younger children, where missing data were more prevalent due to requirements for conditioned responses. The audiometric reference standard included otoscopy, tympanometry, and high frequencies to ensure detection of infection-related and noise-induced hearing loss. RESULTS: Both the mHealth pure-tone screen and DPOAE screen performed better when tympanometry was added to the protocol (increase in sensitivity of 19.9%, 95% Confidence Interval (CI): 15.9 to 24.1 for mHealth screen, 17.9%, 95% CI: 14.0 to 21.8 for high-frequency mHealth screen, and 10.4%, 95% CI: 7.5 to 13.9 for DPOAE). The addition of 6 kHz to the mHealth pure-tone screen provided an 8.7 percentage point improvement in sensitivity (95% CI: 6.5 to 11.3). Completeness of data for both the reference standard and the mHealth screening tool differed substantially by age, due to difficulty with behavioral testing in young children. By age 7, children were able to complete behavioral testing, and data indicated that high-frequency mHealth pure-tone screen with tympanometry was the superior tool for children 7 years and older. For children 3 to 6 years of age, DPOAE plus tympanometry performed the best, both for complete data and multiply imputed data, which better approximates accuracy for children with missing data. CONCLUSIONS: This study directly evaluated pure-tone, DPOAE, and tympanometry tools as part of school hearing screening in rural Alaskan children (3 to 18+ years). Results from this study indicate that tympanometry is a key component in the hearing screening protocol, particularly in environments with higher prevalence of infection-related hearing loss. DPOAE is the preferred hearing screening tool when evaluating children younger than 7 years of age (below 2nd grade in the United States) due to the frequency of missing data with behavioral testing in this age group. For children 7 years and older, the addition of high frequencies to pure-tone screening increased the accuracy of screening, likely due to improved identification of hearing loss from noise exposure. The lack of a consistent reference standard in the literature makes comparing across studies challenging. In our study with a reference standard inclusive of otoscopy, tympanometry, and high frequencies, less than ideal sensitivities were found even for the most sensitive screening protocols, suggesting more investigation is necessary to ensure screening programs are appropriately identifying noise- and infection-related hearing loss in rural, low-resource settings.


Assuntos
Surdez , Perda Auditiva Provocada por Ruído , Criança , Humanos , Pré-Escolar , Alaska , Emissões Otoacústicas Espontâneas/fisiologia , Audiometria de Tons Puros , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas
16.
S D Med ; 76(suppl 6): s26, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37732929

RESUMO

INTRODUCTION: Many orthopedic providers currently treat chronic spondylolysis as self-limited fractures. While the condition has previously been associated with back pain in pediatrics, there has been little attention on the risk of neurologic harm. Electromyography (EMG) is a common study used to evaluate nerve injury, but it has not been previously reported for testing pediatric patients with stress fractures. In this study, pediatric patients with chronic pars fractures and muscle extremity weakness who underwent EMG testing were reviewed to analyze their risk of chronic nerve injury. METHODS: 120 pediatric patients who underwent EMG testing between 2015 and 2021 were analyzed, and 41(21F,20M) patients with a mean age of 16(13-20) met criteria of chronic lumbar pediatric spondylolysis with weakness on ankle dorsiflexion or plantarflexion. No exclusions were made. Initial EMG testing was indicated for the extremity weakness; pain was not the major concern. All exams were completed by JWM. Thin-cut lumbar CT studies were done at the same institution, and EMGs were completed by one of three physiatrists. EMGs were determined as normal, abnormal but not meeting chronic nerve injury threshold, or abnormal and meeting threshold for chronic nerve injury. RESULTS: Of the 41 patients, 33 had bilateral and 8 had unilateral fractures with 95% (39/41) of them located at L4 or L5. 55% (18/33) of the bilateral fractures had abnormal EMGs and demonstrated chronic nerve injury; 1 had an abnormal EMG but did meet chronic injury threshold. 75% (6/8) of the unilateral fractures had abnormal EMGs and demonstrated chronic nerve injury; 1 had an abnormal EMG but did meet chronic injury threshold. Overall, 36% (15/41) had normal EMGs, 5% (2/41) had abnormal results but did not reach chronic injury threshold, and 59% (24/41) met threshold for chronic nerve injury. CONCLUSION: Chronic pars fractures have historically been treated as a benign and self-limited sports injury. However, our analysis showed that 59% of adolescent patients presenting with chronic pars fractures and dorsiflexion or plantarflexion weakness have developed a chronic nerve injury. This study is the first to demonstrate the risk of neurologic harm in unhealed pediatric lumbar stress fractures, and it indicates the importance of EMG testing in young patients presenting with chronic spondylolysis and extremity weakness.


Assuntos
Fraturas de Estresse , Adolescente , Humanos , Criança , Estudos Retrospectivos
17.
Neurobiol Dis ; 170: 105775, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35618205

RESUMO

Neurodegeneration, the progressive loss or damage to neurons and axons, underlies permanent disability in multiple sclerosis (MS); yet its mechanisms are incompletely understood. Recent data indicates autoimmunity to several intraneuronal antigens, including the RNA binding protein (RBP) heterogenous nuclear ribonucleoprotein A1 (hnRNP A1), as contributors to neurodegeneration. We previously showed that addition of anti-hnRNP A1 antibodies, which target the same immunodominant domain of MS IgG, to mice with experimental autoimmune encephalomyelitis (EAE) worsened disease and resulted in an exacerbation of hnRNP A1 dysfunction including cytoplasmic mislocalization of hnRNP A1, stress granule (SG) formation and neurodegeneration in the chronic stages of disease. Because this previous study focused on a singular timepoint during EAE, it is unclear whether anti-hnRNP A1 antibody induced hnRNP A1 dysfunction caused neurodegeneration or was result of it. In the present study, we analyzed in vivo and in vitro models of anti-hnRNP A1 antibody-mediated autoimmunity for markers of hnRNP A1 dysfunction and neurodegeneration over a time course to gain a better understanding of the connection between hnRNP A1 dysfunction and neurodegeneration. Anti-hnRNP A1 antibody treatment resulted in increased neuronal hnRNP A1 mislocalization and nuclear depletion temporally followed by altered RNA expression and SG formation, and lastly an increase in necroptotic signalling and neuronal cell death. Treatment with necrostatin-1s inhibited necroptosis and partially rescued anti-hnRNP A1 antibody-mediated neurodegeneration while clathrin knockdown specifically inhibited anti-hnRNP A1 antibody uptake into neurons. This data identifies a novel antibody-mediated mechanism of neurodegeneration, which may be targeted to inhibit neurodegeneration and prevent permanent neurological decline in persons living with MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Autoimunidade , Ribonucleoproteína Nuclear Heterogênea A1/genética , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Camundongos , Esclerose Múltipla/metabolismo , Degeneração Neural , Neurônios/metabolismo , Ribonucleoproteínas
18.
Ann Neurol ; 89(2): 293-303, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33155696

RESUMO

OBJECTIVE: The aim was to analyze the timeline, prevalence, and survival of rapid eye movement (REM) sleep behavior disorder (RBD) in patients who developed alpha-synucleinopathies (Parkinson disease, dementia with Lewy bodies, and Parkinson disease dementia) compared with age- and sex-matched controls in a population-based incident-cohort study. METHODS: We used a population-based, 1991 to 2010 incident-cohort study of alpha-synucleinopathies. A movement-disorder specialist reviewed medical records to confirm diagnoses. RBD was diagnosed by reported dream-enactment symptoms or polysomnography. Probable RBD and polysomnographically confirmed RBD were analyzed separately and combined. RESULTS: Among the 444 incident cases of alpha-synucleinopathy, 86 were clinically diagnosed with RBD (19.8%), including 30 (35%) by polysomnography and 56 (65%) as probable. The prevalence of idiopathic RBD at alpha-synucleinopathy diagnosis was 3.4%, increasing to 23.8% after 15 years. Cumulative lifetime incidence was 53 times greater in alpha-synucleinopathy patients than in controls (odds ratio [OR] = 53.1, 95% confidence interval [CI]: 13.0-217.2, p < 0.0001), higher in dementia with Lewy bodies than in Parkinson disease (OR = 2.57, 95% CI: 1.50-4.40, p = 0.0004), and higher in men than in women with Parkinson disease, dementia with Lewy bodies, or Parkinson disease dementia (OR = 3.70, 95% CI: 2.07-6.62, p < 0.0001), but did not increase mortality risk. INTERPRETATION: Our cohort had RBD incidence of 3.4%. Overall RBD increased to 23.8% after 15 years, with an overall incidence of 2.5 cases per 100 person-years. With 53 times greater lifetime incidence in alpha-synucleinopathy patients than in controls, RBD was more likely to develop in dementia with Lewy bodies than in Parkinson disease or Parkinson disease dementia, and in men than in women, but did not increase mortality risk within our cohort. ANN NEUROL 2021;89:293-303.


Assuntos
Transtorno do Comportamento do Sono REM/epidemiologia , Sinucleinopatias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Incidência , Doença por Corpos de Lewy/epidemiologia , Doença por Corpos de Lewy/fisiopatologia , Masculino , Mortalidade , Doença de Parkinson/epidemiologia , Doença de Parkinson/fisiopatologia , Polissonografia , Prevalência , Transtorno do Comportamento do Sono REM/fisiopatologia , Distribuição por Sexo , Sinucleinopatias/fisiopatologia
19.
Glob Chang Biol ; 28(20): 5956-5972, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35841134

RESUMO

Agroforestry systems (AFS) contribute to carbon (C) sequestration and reduction in greenhouse gas emissions from agricultural lands. However, previously understudied differences among AFS may underestimate their climate change mitigation potential. In this 3-year field study, we assessed various C stocks and greenhouse gas emissions across two common AFS (hedgerows and shelterbelts) and their component land uses: perennial vegetated areas with and without trees (woodland and grassland, respectively), newly planted saplings in grassland, and adjacent annual cropland in central Alberta, Canada. Between 2018 and 2020 (~April-October), nitrous oxide emissions were 89% lower under perennial vegetation relative to the cropland (0.02 and 0.18 g N m-2  year-1 , respectively). In 2020, heterotrophic respiration in the woodland was 53% lower in shelterbelts relative to hedgerows (279 and 600 g C m-2  year-1 , respectively). Within the woodland, deadwood C stock was particularly important in hedgerows (35 Mg C ha-1 or 7% of ecosystem C) relative to shelterbelts (2 Mg C ha-1 or <1% of ecosystem C), and likely affected C cycling differences between the woodland types by enhancing soil labile C and microbial biomass in hedgerows. Deadwood C stock was positively correlated with annual heterotrophic respiration and total (to ~100 cm depth) soil organic C, water-soluble organic C, and microbial biomass C. Total ecosystem C was 1.90-2.55 times greater within the woodland than all other land uses, with 176, 234, 237, and 449 Mg C ha-1 found in the cropland, grassland, planted saplings treatment, and woodland, respectively. Shelterbelt and hedgerow woodlands contained 2.09 and 3.03 times more C, respectively, than adjacent cropland. Our findings emphasize the importance of AFS for fostering C sequestration and reducing greenhouse gas emissions and, in particular, retaining hedgerows (legacy woodland) and their associated deadwood across temperate agroecosystems will help mitigate climate change.


Assuntos
Gases de Efeito Estufa , Óxido Nitroso , Agricultura , Alberta , Carbono/análise , Sequestro de Carbono , Ecossistema , Gases de Efeito Estufa/análise , Óxido Nitroso/análise , Plantas , Solo , Árvores
20.
Phys Chem Chem Phys ; 24(17): 10085-10094, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35416200

RESUMO

Ion trap quantum computing utilizes electronic states of atomic ions such as Ca+ to encode information on to a qubit. To explore the fundamental properties of Ca+ inside molecular cavities, we describe here a computational study of Ca+ bound inside neutral [n]-cycloparaphenylenes (n = 5-12), often referred to as "nanohoops". This ab initio study characterizes optimized structures, harmonic vibrational frequencies, potential energy surfaces, and ion molecular orbital distortion as functions of increasing nanohoop size. The results of this work provide a first step in guiding experimental studies of the spectroscopy of these ion-molecular cavity complexes.

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