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1.
Sensors (Basel) ; 24(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38931687

RESUMEN

Midlife risk factors such as type 2 diabetes mellitus (T2DM) confer a significantly increased risk of cognitive impairment in later life with executive function, memory, and attention domains often affected first. Spatiotemporal gait characteristics are emerging as important integrative biomarkers of neurocognitive function and of later dementia risk. We examined 24 spatiotemporal gait parameters across five domains of gait previously linked to cognitive function on usual-pace, maximal-pace, and cognitive dual-task gait conditions in 102 middle-aged adults with (57.5 ± 8.0 years; 40% female) and without (57.0 ± 8.3 years; 62.1% female) T2DM. Neurocognitive function was measured using a neuropsychological assessment battery. T2DM was associated with significant changes in gait phases and rhythm domains at usual pace, and greater gait variability observed during maximal pace and dual tasks. In the overall cohort, both the gait pace and rhythm domains were associated with memory and executive function during usual pace. At maximal pace, gait pace parameters were associated with reaction time and delayed memory. During the cognitive dual task, associations between gait variability and both delayed memory/executive function were observed. Associations persisted following covariate adjustment and did not differ by T2DM status. Principal components analysis identified a consistent association of slower gait pace (step/stride length) and increased gait variability during maximal-pace walking with poorer memory and executive function performance. These data support the use of spatiotemporal gait as an integrative biomarker of neurocognitive function in otherwise healthy middle-aged individuals and reveal discrete associations between both differing gait tasks and gait domains with domain-specific neuropsychological performance. Employing both maximal-pace and dual-task paradigms may be important in cognitively unimpaired populations with risk factors for later cognitive decline-with the aim of identifying individuals who may benefit from potential preventative interventions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Marcha , Pruebas Neuropsicológicas , Humanos , Femenino , Persona de Mediana Edad , Masculino , Marcha/fisiología , Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/fisiopatología , Función Ejecutiva/fisiología , Cognición/fisiología , Memoria/fisiología , Anciano
2.
PLoS One ; 19(5): e0302602, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38717979

RESUMEN

OBJECTIVES: The defining achievement of a multi-marathoner is completing 100 marathons. This study aimed to comprehensively document the phenomenon of multi-marathoning, addressing its demographics, culture and participatory nature, filling a gap in peer-reviewed research on the topic. Additionally, it aimed to provide recommendations for multi-marathon governing bodies, event organisers, health professionals and participants to address identified issues. METHODS: A global survey was distributed to participants and individuals interested in multi-marathoning. It was distributed with support from major national and international multi-marathon clubs through their social media channels, email groups and newsletters. The survey was conducted anonymously and online. RESULTS: The survey garnered responses from 830 participants across 40 countries, with an average marathon completion count of 146.54 (SD 201.83) per respondent. Gender distribution showed 60.69% men, 39.3% women and 0.1% gender variant/non-conforming. Respondents' average ages were 51.6 (SD 9.96) years for men, 48.83 (SD 9.15) years for women and 35.00 (SD 8.76) years for gender variant/non-conforming. As participants age, social and travel motivations surpass competitiveness. A majority (57%) of respondents had at least one contravention to the pre-participation screening questionnaire PARQ-+ and 67% reported taking pain relief medication around events. Notably, 93% of respondents reported multi-marathoning as beneficial for their mental health. DISCUSSION: Multi-marathoning accommodates older athletes, but a significant gender imbalance exists in participation levels. Long-term health implications warrant attention from governing bodies, event organisers, health professionals and participants alike. Multi-marathoners should seek medical advice before participation, utilise modern equipment for health monitoring and optimise training accordingly. CONCLUSION: Recommendations include encouraging diversity at events, ensuring event directors have well-resourced health plans and promoting participants' proactive health management before and during their involvement in the sport. This study not only advances our understanding of multi-marathoning as a sport but also contributes to theoretical frameworks such as SDT and HBM.


Asunto(s)
Carrera , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Encuestas y Cuestionarios , Demografía , Cultura , Anciano , Motivación
3.
Transplant Cell Ther ; 30(7): 692.e1-692.e12, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38643958

RESUMEN

The clinical value of serial routine bone marrow aspirates (rBMAs) in the first year after allogeneic hematopoietic cell transplantation (alloHCT) to detect or predict relapse of acute leukemia (AL) and myelodysplastic syndrome (MDS) in pediatric and young adult patients is unclear. The purpose of this analysis was to determine if assessment of minimal residual disease (MRD) by multiparameter flow cytometry (MFC, MFC-MRD) or donor chimerism (DC) in rBMAs or serial complete blood counts (CBCs) done in the year after alloHCT predicted relapse of AL or MDS in pediatric and young adult patients. We completed a retrospective analysis of patients with AL or MDS who had rBMAs performed after alloHCT between January 2012 and June 2018. Bone marrow (BM) was evaluated at approximately 3, 6, and 12 months for disease recurrence by morphology, MFC-MRD, and percent DC by short tandem repeat molecular testing. CBCs were performed at every clinic visit. The main outcome of interest was an assessment of whether MFC-MRD or DC in rBMAs or serial CBCs done in the year after alloHCT predicted relapse in AL or MDS pediatric and young adult patients. A total of 121 recipients with a median age of 13 years (range 1 to 32) were included: 108 with AL and, 13 with MDS. A total of 423 rBMAs (median 3; 0 to 13) were performed. Relapse at 2 years was 23% (95% CI: 16% to 31%) and at 5 years 25% (95% CI: 18% to 33%). One hundred fifty-four of 157 (98%) rBMAs evaluated for MRD by MFC were negative and did not preclude subsequent relapse. Additionally, low DC (<95%) did not predict relapse and high DC (≥95%) did not preclude relapse. For patients alive without relapse at 1 year, BM DC (P = .74) and peripheral T-cell DC (P = .93) did not predict relapse. Six patients with low-level T-cell and/or BM DC had a total of 8 to 20 BM evaluations, none of these patients relapsed. However, CBC results were informative for relapse; 28 of 31 (90%) relapse patients presented with an abnormal CBC with peripheral blood (PB) blasts (16 patients), cytopenias (9 patients), or extramedullary disease (EMD, 3 patients). Two patients with BM blasts >5% on rBMA had circulating blasts within 5 weeks of rBMA. Neutropenia (ANC <1.5 K/mcl) at 1 year was predictive of relapse (P = .01). Neutropenia and thrombocytopenia (<160 K/mcl) were predictive of disease-free survival (DFS) with inferior DFS for ANC <1.5 K/mcl, P = .001, or platelet count <160 K/mcl (P = .04). These results demonstrate rBMAs after alloHCT assessed for MRD by MFC and/or for level of DC are poor predictors for relapse in pediatric and young adult patients with AL or MDS. Relapse in these patients presents with PB blasts, cytopenias, or EMD. ANC and platelet count at 1-year were highly predictive for DFS.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Síndromes Mielodisplásicos , Recurrencia , Humanos , Síndromes Mielodisplásicos/terapia , Niño , Masculino , Adolescente , Femenino , Adulto Joven , Adulto , Preescolar , Estudios Retrospectivos , Médula Ósea/patología , Neoplasia Residual , Leucemia/terapia , Lactante , Enfermedad Aguda , Citopenia
4.
Transplant Cell Ther ; 30(5): 457-461, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38677788
5.
Cytotherapy ; 26(5): 466-471, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38430078

RESUMEN

BACKGROUND AIMS: Daratumumab, a human IgG monoclonal antibody targeting CD38, is a promising treatment for pediatric patients with relapsed or refractory T-cell acute lymphoblastic leukemia (T-ALL). We describe a case of delayed engraftment following a mismatched, unrelated donor hematopoietic stem cell transplant (HSCT) in a 14-year-old female with relapsed T-ALL, treated with daratumumab and chemotherapy. By Day 28 post-HSCT, the patient had no neutrophil engraftment but full donor myeloid chimerism. METHODS: We developed two novel, semi-quantitative, antibody-based assays to measure the patient's bound and plasma daratumumab levels to determine if prolonged drug exposure may have contributed to her slow engraftment. RESULTS: Daratumumab levels were significantly elevated more than 30 days after the patient's final infusion, and levels inversely correlated with her white blood cell counts. To clear daratumumab, the patient underwent several rounds of plasmapheresis and subsequently engrafted. CONCLUSIONS: This is the first report of both delayed daratumumab clearance and delayed stem cell engraftment following daratumumab treatment in a pediatric patient. Further investigation is needed to elucidate the optimal dosing of daratumumab for treatment of acute leukemias in pediatric populations as well as daratumumab's potential effects on hematopoietic stem cells and stem cell engraftment following allogenic HSCT.


Asunto(s)
Anticuerpos Monoclonales , Trasplante de Células Madre Hematopoyéticas , Trasplante Homólogo , Humanos , Trasplante de Células Madre Hematopoyéticas/métodos , Femenino , Anticuerpos Monoclonales/uso terapéutico , Adolescente , Trasplante Homólogo/métodos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Supervivencia de Injerto/efectos de los fármacos
6.
Artículo en Inglés | MEDLINE | ID: mdl-38436476

RESUMEN

BACKGROUND: Although type 2 diabetes mellitus (T2DM) is an established risk factor for cognitive impairment, the underlying mechanisms remain poorly explored. One potential mechanism may be through effects of T2DM on cerebral perfusion. The current study hypothesized that T2DM is associated with altered peripheral and central hemodynamic responses to orthostasis, which may in turn be associated with cognitive impairment in T2DM. METHODS: A novel use of function-on-scalar regression, which allows the entire hemodynamic response curve to be modeled, was employed to assess the association between T2DM and hemodynamic responses to orthostasis. Logistic regression was used to assess the relationship between tissue saturation index (TSI), T2DM, and cognitive impairment. All analyses used cross-sectional data from Wave 3 of The Irish Longitudinal Study on Ageing (TILDA). RESULTS: Of 2 984 older adults (aged 64.3 ±â€…8.0; 55% female), 189 (6.3%) had T2DM. T2DM was associated with many features that are indicative of autonomic dysfunction including a blunted peak heart rate and lower diastolic blood pressure. T2DM was associated with reduced TSI and also with greater odds of impaired performance on the Montreal Cognitive Assessment (odds ratio [OR]: 1.62; confidence interval [CI: 1.07, 2.56]; p = .019). Greater TSI was associated with lower odds of impaired performance (OR: 0.90, CI [0.81-0.99]; p = .047). CONCLUSIONS: T2DM was associated with impaired peripheral and cerebral hemodynamic responses to active stand. Both T2DM and reduced cerebral perfusion were associated with impaired cognitive performance. Altered cerebral perfusion may represent an important mechanism linking T2DM and adverse brain health outcomes in older adults.


Asunto(s)
Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Humanos , Femenino , Anciano , Masculino , Diabetes Mellitus Tipo 2/complicaciones , Estudios Longitudinales , Mareo , Estudios Transversales , Disfunción Cognitiva/etiología , Hemodinámica
7.
Cytotherapy ; 26(4): 351-359, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38349310

RESUMEN

BACKGROUND AIMS: Traditional weight-based dosing of rabbit anti-thymocyte globulin (rATG) used in allogeneic hematopoietic cell transplantation (HCT) to prevent graft-versus-host disease (GVHD) and graft rejection leads to variable exposures. High exposures induce delayed CD4+immune reconstitution (CD4+IR) and greater mortality. We sought to determine the impact of rATG exposure in children and young adults receiving various types of EX-VIVO T-cell-depleted (EX-VIVO-TCD) HCT. METHODS: Patients receiving their first EX-VIVO-TCD HCT (CliniMACS CD34+, Isolex or soybean lectin agglutination), with removal of residual T cells by E-rosette depletion (E-) between 2008 and 2018 at Memorial Sloan Kettering Cancer Center were retrospectively analyzed. rATG exposure post-HCT was estimated (AU*d/L) using a validated population pharmacokinetic model. Previously defined rATG-exposures, <30, 30-55, ≥55 AU*d/L, were related with outcomes of interest. Cox proportional hazard and cause-specific models were used for analyses. RESULTS: In total, 180 patients (median age 11 years; range 0.1-44 years) were included, malignant 124 (69%) and nonmalignant 56 (31%). Median post-HCT rATG exposure was 32 (0-104) AU*d/L. Exposure <30 AU*d/L was associated with a 3-fold greater probability of CD4+IR (P < 0.001); 2- to 4-fold lower risk of death (P = 0.002); and 3- to 4-fold lower risk of non-relapse mortality (NRM) (P = 0.02). Cumulative incidence of NRM was 8-fold lower in patients who attained CD4+IR compared with those who did not (P < 0.0001). There was no relation between rATG exposure and aGVHD (P = 0.33) or relapse (P = 0.23). Effect of rATG exposure on outcomes was similar in three EX-VIVO-TCD methods. CONCLUSIONS: Individualizing rATG dosing to target a low rATG exposure post-HCT while maintaining total cumulative exposure may better predict CD4+IR, reduce NRM and increase overall survival, independent of the EX-VIVO-TCD method.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Niño , Adulto Joven , Suero Antilinfocítico , Estudios Retrospectivos , Linfocitos T , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Acondicionamiento Pretrasplante
8.
Lancet Oncol ; 25(3): 376-387, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309282

RESUMEN

BACKGROUND: Survival in Epstein-Barr virus (EBV)-positive post-transplant lymphoproliferative disease following haematopoietic stem-cell transplant (HSCT) or solid organ transplant (SOT) is poor after failure of initial therapy, indicating an urgent need for therapies for this ultra-rare disease. With recent EU marketing authorisation, tabelecleucel is the first off-the-shelf, allogeneic, EBV-specific T-cell immunotherapy to receive approval for treatment of relapsed or refractory EBV-positive post-transplant lymphoproliferative disease. We aimed to determine the clinical benefit of tabelecleucel in patients with relapsed or refractory EBV-positive post-transplant lymphoproliferative disease following HSCT or SOT. METHODS: In this global, multicentre, open-label, phase 3 trial, eligible patients (of any age) had biopsy-proven EBV-positive post-transplant lymphoproliferative disease, disease that was relapsed or refractory to rituximab after HSCT and rituximab with or without chemotherapy after SOT, and partially HLA-matched and appropriately HLA-restricted tabelecleucel available. Patients received tabelecleucel administered intravenously at 2 × 106 cells per kg on days 1, 8, and 15 in 35-day cycles and are assessed for up to 5 years for survival post-treatment initiation. The primary endpoint was objective response rate. All patients who received at least one dose of tabelecleucel were included in safety and efficacy analyses. This trial is registered with ClinicalTrials.gov, NCT03394365, and is ongoing. FINDINGS: From June 27, 2018, to Nov 5, 2021, 63 patients were enrolled, of whom 43 (24 [56%] male and 19 [44%] female) were included, 14 had prior HSCT, 29 had SOT. Seven (50%, 95% CI 23-77) of 14 participants in the HSCT group and 15 (52%, 33-71) of 29 participants in the SOT group had an objective response, with a median follow-up of 14·1 months (IQR 5·7-23·9) and 6·0 months (1·8-18·4), respectively. The most common grade 3 or 4 treatment-emergent adverse events were disease progression (in four [29%] of 14 in HSCT and eight [28%] of 29 in SOT) and decreased neutrophil count (in four [29%] of 14 in HSCT and four [14%] of 29 in SOT). Treatment-emergent serious adverse events were reported in 23 (53%) of 43 patients and fatal treatment-emergent adverse events in five (12%); no fatal treatment-emergent adverse event was treatment-related. There were no reports of tumour flare reaction, cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, transmission of infectious diseases, marrow rejection, or infusion reactions. No events of graft-versus-host disease or SOT rejection were reported as related to tabelecleucel. INTERPRETATION: Tabelecleucel provides clinical benefit in patients with relapsed or refractory EBV-positive post-transplant lymphoproliferative disease, for whom there are no other approved therapies, without evidence of safety concerns seen with other adoptive T-cell therapies. These data represent a potentially transformative and accessible treatment advance for patients with relapsed or refractory disease with few treatment options. FUNDING: Atara Biotherapeutics.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Trasplante de Células Madre Hematopoyéticas , Trastornos Linfoproliferativos , Trasplante de Órganos , Humanos , Masculino , Femenino , Rituximab/efectos adversos , Herpesvirus Humano 4/genética , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Infecciones por Virus de Epstein-Barr/etiología , Alelos , Trastornos Linfoproliferativos/tratamiento farmacológico , Trastornos Linfoproliferativos/etiología , Trasplante de Órganos/efectos adversos , Trasplante de Células Madre Hematopoyéticas/efectos adversos
9.
Pediatr Hematol Oncol ; : 1-11, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38379214

RESUMEN

Management of the exposure of pediatric oncology patients to varicella zoster virus (VZV) is controversial. We report the exposure of 56 patients to a single child with chicken pox at a pediatric cancer housing facility and describe our strategic approach for their management. We reviewed the immune and clinical status of 56 children with cancer receiving ongoing treatment at Memorial Sloan Kettering Cancer Center (MSK) who, while living at a pediatric cancer housing facility, were exposed to the index patient. The management of patients exposed included: (1) determination of immune status, (2) availability of vaccination history or VZV disease prophylaxis, (3) exposure status and subsequent isolation during the period of incubation, and (4) VZV disease prophylaxis. In addition to the 56 patients exposed to the index case, eight children with cancer treated at other facilities and 11 healthy siblings living in the facility were exposed. Of the 56 MSK patients, 21 were classified as immunosuppressed and received varicella zoster immune globulin (human), intravenous standard immune globulin, or acyclovir based on serostatus and immune function. The cohort was followed for 4 weeks after the exposure and no secondary infections were diagnosed. We performed a risk assessment and created a management plan to control and prevent further exposure and development of disease. No secondary cases developed. This strategic approach could serve as a model for the management of VZV exposure for other pediatric oncology centers.

10.
Clin Immunol ; 261: 109942, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38367737

RESUMEN

Severe combined immunodeficiency (SCID) is characterized by a severe deficiency in T cell numbers. We analyzed data collected (n = 307) for PHA-based T cell proliferation from the PIDTC SCID protocol 6901, using either a radioactive or flow cytometry method. In comparing the two groups, a smaller number of the patients tested by flow cytometry had <10% of the lower limit of normal proliferation as compared to the radioactive method (p = 0.02). Further, in patients with CD3+ T cell counts between 51 and 300 cells/µL, there was a higher proliferative response with the PHA flow assay compared to the 3H-T assay (p < 0.0001), suggesting that the method of analysis influences the resolution and interpretation of PHA results. Importantly, we observed many SCID patients with profound T cell lymphopenia having normal T cell proliferation when assessed by flow cytometry. We recommend this test be considered only as supportive in the diagnosis of typical SCID.


Asunto(s)
Linfopenia , Inmunodeficiencia Combinada Grave , Recién Nacido , Humanos , Inmunodeficiencia Combinada Grave/diagnóstico , Linfopenia/diagnóstico , Tamizaje Neonatal/métodos , Linfocitos T , Proliferación Celular
11.
J Allergy Clin Immunol ; 153(1): 287-296, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37793572

RESUMEN

BACKGROUND: The Primary Immune Deficiency Treatment Consortium (PIDTC) enrolled children in the United States and Canada onto a retrospective multicenter natural history study of hematopoietic cell transplantation (HCT). OBJECTIVE: We investigated outcomes of HCT for severe combined immunodeficiency (SCID). METHODS: We evaluated the chronic and late effects (CLE) after HCT for SCID in 399 patients transplanted from 1982 to 2012 at 32 PIDTC centers. Eligibility criteria included survival to at least 2 years after HCT without need for subsequent cellular therapy. CLE were defined as either conditions present at any time before 2 years from HCT that remained unresolved (chronic), or new conditions that developed beyond 2 years after HCT (late). RESULTS: The cumulative incidence of CLE was 25% in those alive at 2 years, increasing to 41% at 15 years after HCT. CLE were most prevalent in the neurologic (9%), neurodevelopmental (8%), and dental (8%) categories. Chemotherapy-based conditioning was associated with decreased-height z score at 2 to 5 years after HCT (P < .001), and with endocrine (P < .001) and dental (P = .05) CLE. CD4 count of ≤500 cells/µL and/or continued need for immunoglobulin replacement therapy >2 years after transplantation were associated with lower-height z scores. Continued survival from 2 to 15 years after HCT was 90%. The presence of any CLE was associated with increased risk of late death (hazard ratio, 7.21; 95% confidence interval, 2.71-19.18; P < .001). CONCLUSION: Late morbidity after HCT for SCID was substantial, with an adverse impact on overall survival. This study provides evidence for development of survivorship guidelines based on disease characteristics and treatment exposure for patients after HCT for SCID.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Inmunodeficiencia Combinada Grave , Niño , Humanos , Inmunodeficiencia Combinada Grave/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Incidencia , Canadá/epidemiología , Estudios Retrospectivos , Acondicionamiento Pretrasplante
12.
Bone Marrow Transplant ; 59(1): 23-33, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773270

RESUMEN

The only curative approach for myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) arising in patients with Fanconi anemia (FA) is allogeneic hematopoietic stem cell transplantation (HCT); however, HCT approaches are inconsistent and limited data on outcomes exist. We retrospectively evaluated outcomes of thirty patients with FA and MDS/AML who underwent first allogeneic HCT with a T-cell depleted (TCD) graft at our institution. Patients were transplanted on successive protocols with stepwise changes in cytoreduction and GVHD prophylaxis. All but two patients (93%) experienced durable hematopoietic engraftment. With median follow-up of 8.7 years, 5-year OS was 66.8% and DFS 53.8%. No significant differences in survival were found in patients with high-risk prognostic features (age ≥20 years, AML diagnosis, alternative donor graft) or when stratified by conditioning regimen. The 5-year cumulative incidences of relapse and NRM were 24.3% and 21.9%, respectively. NRM was higher in patients ≥20 years at HCT but did not otherwise differ. We herein demonstrate promising outcomes following allogeneic HCT for patients with FA and MDS/AML using TCD grafts, particularly in a cohort of high-risk patients with 50% ≥20 years and a majority receiving mismatched grafts. Future prospective studies are needed to compare this approach with other HCT platforms.


Asunto(s)
Anemia de Fanconi , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Adulto Joven , Adulto , Anemia de Fanconi/terapia , Anemia de Fanconi/complicaciones , Estudios Retrospectivos , Trasplante Homólogo/efectos adversos , Acondicionamiento Pretrasplante/métodos , Linfocitos T , Trasplante de Células Madre Hematopoyéticas/métodos , Enfermedad Injerto contra Huésped/etiología
13.
Nat Commun ; 14(1): 7789, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38040720

RESUMEN

Even prior to producing their first words, infants are developing a sophisticated speech processing system, with robust word recognition present by 4-6 months of age. These emergent linguistic skills, observed with behavioural investigations, are likely to rely on increasingly sophisticated neural underpinnings. The infant brain is known to robustly track the speech envelope, however previous cortical tracking studies were unable to demonstrate the presence of phonetic feature encoding. Here we utilise temporal response functions computed from electrophysiological responses to nursery rhymes to investigate the cortical encoding of phonetic features in a longitudinal cohort of infants when aged 4, 7 and 11 months, as well as adults. The analyses reveal an increasingly detailed and acoustically invariant phonetic encoding emerging over the first year of life, providing neurophysiological evidence that the pre-verbal human cortex learns phonetic categories. By contrast, we found no credible evidence for age-related increases in cortical tracking of the acoustic spectrogram.


Asunto(s)
Corteza Auditiva , Percepción del Habla , Adulto , Lactante , Humanos , Fonética , Corteza Auditiva/fisiología , Percepción del Habla/fisiología , Habla/fisiología , Acústica , Estimulación Acústica
14.
Neurobiol Aging ; 132: 233-245, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37866083

RESUMEN

The underlying neural mechanisms underpinning the association between age-related hearing loss (ARHL) and dementia remain unclear. A limitation has been the lack of functional neuroimaging studies in ARHL cohorts to help clarify this relationship. In the present study, we investigated the neural correlates of feature binding in visual working memory with ARHL (controls = 14, mild HL = 21, and moderate or greater HL = 23). Participants completed a visual change detection task assessing feature binding while their neural activity was synchronously recorded via high-density electroencephalography. There was no difference in accuracy scores for ARHL groups compared to controls. There was increased electrophysiological activity in those with ARHL, particularly in components indexing the earlier stages of visual cognitive processing. This activity was more pronounced with more severe ARHL and was associated with maintained feature binding. Source space (sLORETA) analyses indicated greater activity in networks modulated by frontoparietal and temporal regions. Our results demonstrate there may be increased involvement of neurocognitive control networks to maintain lower-order neurocognitive processing disrupted by ARHL.


Asunto(s)
Memoria a Corto Plazo , Presbiacusia , Humanos , Percepción Visual , Electroencefalografía
15.
Eur J Neurosci ; 58(6): 3402-3411, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37655756

RESUMEN

Non-invasive sensory stimulation in the range of the brain's gamma rhythm (30-100 Hz) is emerging as a new potential therapeutic strategy for the treatment of Alzheimer's disease (AD). Here, we investigated the effect of repeated combined exposure to 40 Hz synchronized sound and light stimuli on hippocampal long-term potentiation (LTP) in vivo in three rat models of early AD. We employed a very complete model of AD amyloidosis, amyloid precursor protein (APP)-overexpressing transgenic McGill-R-Thy1-APP rats at an early pre-plaque stage, systemic treatment of transgenic APP rats with corticosterone modelling certain environmental AD risk factors and, importantly, intracerebral injection of highly disease-relevant AD patient-derived synaptotoxic beta-amyloid and tau in wild-type animals. We found that daily treatment with 40 Hz sensory stimulation for 2 weeks fully abrogated the inhibition of LTP in all three models. Moreover, there was a negative correlation between the magnitude of LTP and the level of active caspase-1 in the hippocampus of transgenic APP animals, which suggests that the beneficial effect of 40 Hz stimulation was dependent on modulation of pro-inflammatory mechanisms. Our findings support ongoing clinical trials of gamma-patterned sensory stimulation in early AD.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratas , Enfermedad de Alzheimer/terapia , Plasticidad Neuronal , Potenciación a Largo Plazo , Ratas Transgénicas , Precursor de Proteína beta-Amiloide/genética
16.
J Immunother Cancer ; 11(9)2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37775115

RESUMEN

BACKGROUND: Certain phosphorylated peptides are differentially presented by major histocompatibility complex (MHC) molecules on cancer cells characterized by aberrant phosphorylation. Phosphopeptides presented in complex with the human leukocyte antigen HLA-A*02:01 provide a stability advantage over their non-phosphorylated counterparts. This stability is thought to contribute to enhanced immunogenicity. Whether tumor-associated phosphopeptides presented by other common alleles exhibit immunogenicity and structural characteristics similar to those presented by A*02:01 is unclear. Therefore, we determined the identity, structural features, and immunogenicity of phosphopeptides presented by the prevalent alleles HLA-A*03:01, HLA-A*11:01, HLA-C*07:01, and HLA-C*07:02. METHODS: We isolated peptide-MHC complexes by immunoprecipitation from 11 healthy and neoplastic tissue samples using mass spectrometry, and then combined the resulting data with public immunopeptidomics data sets to assemble a curated set of phosphopeptides presented by 96 samples spanning 20 distinct healthy and neoplastic tissue types. We determined the biochemical features of selected phosphopeptides by in vitro binding assays and in silico docking, and their immunogenicity by analyzing healthy donor T cells for phosphopeptide-specific multimer binding and cytokine production. RESULTS: We identified a subset of phosphopeptides presented by HLA-A*03:01, A*11:01, C*07:01 and C*07:02 on multiple tumor types, particularly lymphomas and leukemias, but not healthy tissues. These phosphopeptides are products of genes essential to lymphoma and leukemia survival. The presented phosphopeptides generally exhibited similar or worse binding to A*03:01 than their non-phosphorylated counterparts. HLA-C*07:01 generally presented phosphopeptides but not their unmodified counterparts. Phosphopeptide binding to HLA-C*07:01 was dependent on B-pocket interactions that were absent in HLA-C*07:02. While HLA-A*02:01 and HLA-A*11:01 phosphopeptide-specific T cells could be readily detected in an autologous setting even when the non-phosphorylated peptide was co-presented, HLA-A*03:01 or HLA-C*07:01 phosphopeptides were repeatedly non-immunogenic, requiring use of allogeneic T cells to induce phosphopeptide-specific T cells. CONCLUSIONS: Phosphopeptides presented by multiple alleles that are differentially expressed on tumors constitute tumor-specific antigens that could be targeted for cancer immunotherapy, but the immunogenicity of such phosphopeptides is not a general feature. In particular, phosphopeptides presented by HLA-A*02:01 and A*11:01 exhibit consistent immunogenicity, while phosphopeptides presented by HLA-A*03:01 and C*07:01, although appropriately presented, are not immunogenic. Thus, to address an expanded patient population, phosphopeptide-targeted immunotherapies should be wary of allele-specific differences.


Asunto(s)
Neoplasias , Fosfopéptidos , Humanos , Antígenos de Neoplasias , Alelos , Antígenos HLA-C , Antígenos de Histocompatibilidad , Neoplasias/genética , Neoplasias/terapia , Complejo Mayor de Histocompatibilidad , Inmunoterapia , Antígenos HLA-A
17.
Gait Posture ; 105: 125-131, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37542885

RESUMEN

BACKGROUND: The Sit-to-Stand (STS) transition is one of the most used activities of daily living and vital for independence. Neurological, or physical injuries impairing functional mobility or sensory feedback often require rehabilitative programs or therapeutic interventions. Understanding the biomechanical elements of daily movements and the interaction between these elements may help inform rehabilitation protocols and optimize targeted interventions, such as stimulation protocols. RESEARCH QUESTION: What are the effects of different initial knee angle, arm facilitation and proprioceptive input on leg muscle activation patterns and balance during and after a sit-to-stand? METHODS: EMG of four lower limb muscles were recorded in 20 healthy participants as well centre-of-pressure sway amplitude and velocity, as participants stood from a seated position. Initial knee angles were set to various levels of extension (80°, 90°, 100°) and surface stability and arm facilitation were altered using a foam mat or crossing arms. Data were analysed across 3 phases of the STS transition. RESULTS: More extended knee angles resulted in greater mediolateral sway during each phase (p < .01) and had a detrimental effect on anterior-posterior sway in phases 1 and 3. EMG data suggested more extended initial knee angles also increased EMG activity of the Tibialis Anterior (p < .001) and Bicep Femoris (p < .02) within Phases 1 and 2 to assist lift and stabilisation. SIGNIFICANCE: Findings of this study outline phase-based muscle involvement as well as the compounding effects of reduced proprioceptive input and knee angle, on difficulty of the STS transition. Such results emphasising the need to take sensory and mobility issues into consideration when designing rehabilitative programs or stimulation control systems.


Asunto(s)
Actividades Cotidianas , Extremidad Inferior , Humanos , Articulación de la Rodilla/fisiología , Movimiento/fisiología , Músculo Esquelético/fisiología , Fenómenos Biomecánicos , Electromiografía
18.
Adv Neurobiol ; 31: 195-210, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37338703

RESUMEN

Adult-onset idiopathic focal dystonias (AOIFD) are the most common type of dystonia. It has varied expression including multiple motor (depending on body part affected) and non-motor symptoms (psychiatric, cognitive and sensory). The motor symptoms are usually the main reason for presentation and are most often treated with botulinum toxin. However, non-motor symptoms are the main predictors of quality of life and should be addressed appropriately, as well as treating the motor disorder. Rather than considering AOIFD as a movement disorder, a syndromic approach should be taken, one that accommodates all the symptoms. Dysfunction of the collicular-pulvinar-amygdala axis, with the superior colliculus as a central node, can explain the diverse expression of this syndrome.


Asunto(s)
Trastornos Distónicos , Trastornos del Movimiento , Pulvinar , Adulto , Humanos , Calidad de Vida , Trastornos Distónicos/diagnóstico , Amígdala del Cerebelo
19.
Adv Neurobiol ; 31: 177-194, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37338702

RESUMEN

Adult-onset isolated focal dystonia (AOIFD) is a network disorder characterised by abnormalities of sensory processing and motor control. These network abnormalities give rise to both the phenomenology of dystonia and the epiphenomena of altered plasticity and loss of intracortical inhibition. Existing modalities of deep brain stimulation effectively modulate parts of this network but are limited both in terms of targets and invasiveness. Novel approaches using a variety of non-invasive neuromodulation techniques including transcranial stimulation and peripheral stimulation present an interesting alternative approach and may, in conjunction with rehabilitative strategies, have a role in tailored therapies targeting the underlying network abnormality behind AOIFD.


Asunto(s)
Distonía , Trastornos Distónicos , Adulto , Humanos , Distonía/terapia , Trastornos Distónicos/terapia
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