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1.
Emerg Med Australas ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39268658

RESUMO

OBJECTIVE: To explore how clinicians understand coaching and their clinician-coach practice in emergency medicine. METHODS: Participants were surveyed about the value of coaching and their beliefs about the enablers of, and barriers to, being a clinician-coach. RESULTS: Three themes were developed for the value of coaching: empowerment and growth; enhanced interpersonal dynamics; and reflective transformation. Key enablers were supportive infrastructure, self-driven development and recognition of value. Key barriers were time constraints and scheduling conflicts, cultural challenges and financial and structural obstacles. CONCLUSIONS: Fostering a supportive environment for coaching could significantly enhance clinician competence and well-being, healthcare delivery and professional development.

2.
Leukemia ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237634

RESUMO

The phase 3 COMMODORE trial evaluated gilteritinib versus salvage chemotherapy (SC) in a predominantly Asian relapsed/refractory (R/R) FLT3-mutated (FLT3mut+) acute myeloid leukemia (AML) patient population. The primary endpoint was overall survival (OS); secondary endpoints included event-free survival (EFS) and complete remission (CR) rate. As of June 30, 2020 (interim analysis: 32.2 months after study initiation), 234 patients were randomized (gilteritinib, n = 116; SC, n = 118). Median OS was significantly longer with gilteritinib versus SC (9.6 vs. 5.0 months; HR 0.566 [95% CI: 0.392, 0.818]; p = 0.00211) with a median follow-up of 10.3 months. Median EFS was also significantly longer with gilteritinib (2.8 vs. 0.6 months; HR 0.551 [95% CI: 0.395, 0.769]; p = 0.00004). CR rates with gilteritinib and SC were 16.4% and 10.2%, respectively; composite CR rates were 50.0% and 20.3%, respectively. Exposure-adjusted grade ≥3 adverse event (AE) rates were lower with gilteritinib (58.38 events/patient-year [E/PY]) versus SC (168.30 E/PY). Common AEs with gilteritinib were anemia (77.9%) and thrombocytopenia (45.1%). Gilteritinib plasma concentration peaked ~4 h postdose; ~3-fold accumulation occurred with multiple dosing. The COMMODORE trial demonstrated that gilteritinib significantly improved OS and EFS in predominantly Asian patients, validating the outcomes of gilteritinib from the ADMIRAL trial in R/R FLT3mut+ AML.

3.
Nat Commun ; 15(1): 7803, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242627

RESUMO

Phenomena of free-electron X-ray radiation are treated almost exclusively with classical electrodynamics, despite the intrinsic interaction being that of quantum electrodynamics. The lack of quantumness arises from the vast disparity between the electron energy and the much smaller photon energy, resulting in a small cross-section that makes quantum effects negligible. Here we identify a fundamentally distinct phenomenon of electron radiation that bypasses this energy disparity, and thus displays extremely strong quantum features. This phenomenon arises when free-electron transverse scattering occurs during the radiation process, creating entanglement between each transversely recoiled electron and the photons it emitted. This phenomenon profoundly modifies the characteristics of free-electron radiation mediated by crystals, compared to conventional classical analysis and even previous quantum analysis. We also analyze conditions to detect this phenomenon using low-emittance electron beams and high-resolution X-ray spectrometers. These quantum radiation features could guide the development of compact coherent X-ray sources facilitated by nanophotonics and quantum optics.

4.
Nat Rev Genet ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138293

RESUMO

Histones are integral components of eukaryotic chromatin that have a pivotal role in the organization and function of the genome. The dynamic regulation of chromatin involves the incorporation of histone variants, which can dramatically alter its structural and functional properties. Contrary to an earlier view that limited individual histone variants to specific genomic functions, new insights have revealed that histone variants exert multifaceted roles involving all aspects of genome function, from governing patterns of gene expression at precise genomic loci to participating in genome replication, repair and maintenance. This conceptual change has led to a new understanding of the intricate interplay between chromatin and DNA-dependent processes and how this connection translates into normal and abnormal cellular functions.

5.
J Neurodev Disord ; 16(1): 36, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961335

RESUMO

OBJECTIVE: Rett syndrome (RTT) is characterized by neurological regression. This pioneering study investigated the effect of age on brain volume reduction by analyzing magnetic resonance imaging findings in participants with RTT, ranging from toddlers to adults. METHODS: Functional evaluation and neuroimaging were performed. All scans were acquired using a Siemens Tim Trio 3 T scanner with a 32-channel head coil. RESULTS: The total intracranial volume and cerebral white matter volume significantly increased with age in the control group compared with that in the RTT group (p < 0.05). Cortical gray matter volume reduction in the RTT group continued to increase in bilateral parietal lobes and left occipital lobes (p < 0.05). The differences in cortical gray matter volume between typically developing brain and RTT-affected brain may tend to continuously increase until adulthood in both temporal lobes although not significant after correction for multiple comparison. CONCLUSIONS: A significant reduction in brain volume was observed in the RTT group. Cortical gray matter volume in the RTT group continued to reduce in bilateral parietal lobes and left occipital lobes. These results provide a baseline for future studies on the effect of RTT treatment and related neuroscience research.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Síndrome de Rett , Humanos , Síndrome de Rett/diagnóstico por imagem , Síndrome de Rett/fisiopatologia , Síndrome de Rett/patologia , Feminino , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/crescimento & desenvolvimento , Adulto , Criança , Adulto Jovem , Pré-Escolar , Adolescente , Taiwan , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Masculino , Tamanho do Órgão , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
6.
Methods Mol Biol ; 2826: 47-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39017884

RESUMO

Immunofluorescence microscopy is a powerful technique using fluorescently labelled antibodies which can be used to visualize proteins in the nucleus. A key advantage of this method is that it can provide insight into the spatial organization and the localization of nuclear proteins, which can provide elucidation of their function. Here, we provide a protocol for immunofluorescence staining in the nucleus, which has successfully been used to visualize histone modifications and nuclear bodies in human and mouse B lymphocytes, using as few as 1 × 104-5 × 104 cells.


Assuntos
Epigênese Genética , Imunofluorescência , Animais , Camundongos , Imunofluorescência/métodos , Humanos , Núcleo Celular/metabolismo , Subpopulações de Linfócitos B/metabolismo , Subpopulações de Linfócitos B/imunologia , Memória Imunológica , Microscopia de Fluorescência/métodos , Histonas/metabolismo , Ativação Linfocitária , Coloração e Rotulagem/métodos
7.
Chemosphere ; 364: 142966, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39074666

RESUMO

Glyphosate, the most widely used herbicide in the United States, is applied to control broadleaf weeds and grasses. Public concern is mounting over how pesticides affect human and environmental health. Glyphosate toxicity in animals is known, but human carcinogenicity is controversial, and limited epidemiologic evidence suggests associations between exposure and respiratory diseases (e.g., asthma) and adverse child neurodevelopment. Understanding the extent of the general U.S. population exposure to glyphosate is important. To examine temporal trends in exposure to glyphosate, we determined urinary concentrations of glyphosate among U.S. children and adults from three cycles of the National Health and Nutrition Examination Survey (NHANES) conducted 2013-2018. Most of the population (70.0%-81.7%, depending on cycle) was exposed, including children as young as 3 years of age. Concentrations decreased from 2013 to 2018 by 38%; the decline was smaller in younger age groups. The downward trend likely reflects changes in glyphosate use resulting, at least in part, from changes in agricultural practices, regulatory actions, and shifts in public awareness regarding glyphosate toxicity. Continuing glyphosate biomonitoring will help understand how changes in use and actions to restrict applications of this common pesticide affect human exposures.

9.
Autism ; : 13623613241254620, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853381

RESUMO

LAY ABSTRACT: Sleep problems are common and impactful among individuals with Rett syndrome (RTT) and their caregivers. We examined the sleep patterns of 29 RTT patients and their primary caregivers using various assessment tools. The study found that a majority of the patients experienced sleep disturbances, with younger patients showing more sleep difficulties. Caregivers also reported poor sleep quality. The findings emphasize the need to address sleep problems in RTT management, as improving sleep quality can positively impact the well-being of individuals with RTT and their caregivers.

10.
iScience ; 27(5): 109629, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38616920

RESUMO

ATR-X (alpha thalassemia, mental retardation, X-linked) syndrome features genital and testicular abnormalities including atypical genitalia and small testes with few seminiferous tubules. Our mouse model recapitulated the testicular defects when Atrx was deleted in Sertoli cells (ScAtrxKO) which displayed G2/M arrest and apoptosis. Here, we investigated the mechanisms underlying these defects. In control mice, Sertoli cells contain a single novel "GATA4 PML nuclear body (NB)" that contained the transcription factor GATA4, ATRX, DAXX, HP1α, and PH3 and co-localized with the Y chromosome short arm (Yp). ScAtrxKO mice contain single giant GATA4 PML-NBs with frequent DNA double-strand breaks (DSBs) in G2/M-arrested apoptotic Sertoli cells. HP1α and PH3 were absent from giant GATA4 PML-NBs indicating a failure in heterochromatin formation and chromosome condensation. Our data suggest that ATRX protects a Yp region from DNA damage, thereby preventing Sertoli cell death. We discuss Y chromosome damage/decondensation as a mechanism for testicular failure.

11.
J Formos Med Assoc ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38431481

RESUMO

BACKGROUND: The incidence of pediatric hospitalizations has significantly increased since the spread of the omicron variant of COVID-19. Changes of characteristics in respiratory and neurological symptoms have been reported. We performed a retrospective, cross-sectional study to characterize the MRI change in children with an emphasis on the change of cerebral vasculatures. METHODS: We retrospectively collected clinical and MRI data of 31 pediatric patients with neurological symptoms during the acute infection and abnormalities on MRI during the outbreak of omicron variant from April 2022 to June 2022 in Taiwan. The clinical manifestations and MRI abnormalities were collected and proportion of patients with vascular abnormalities was calculated. RESULTS: Among 31 pediatric patients with post-COVID-19 neurological symptoms, MRI abnormalities were observed in 15 (48.4%), predominantly encephalitis/encephalopathy (73.3%). Notable MRI findings included focal diffusion-weighted imaging (DWI) hyperintensity in cerebral cortex and thalamus, diffuse cortical T2/DWI hyperintensity, and lesions in the medulla, pons, cerebellum, and splenium of corpus callosum. Vascular abnormalities were seen in 12 (80%) patients with MRI abnormalities, mainly affecting the middle cerebral arteries. The spectrum of neurological manifestations ranged from seizures to Alice in Wonderland syndrome, underscoring the diverse impact of COVID-19 on pediatric patients. CONCLUSION: A high proportion of vascular abnormalities was observed in pediatric patients with neurological involvements, suggesting that vascular involvement is an important mechanism of neurological manifestations in omicron variant infection.

12.
N Engl J Med ; 390(11): 994-1008, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38477987

RESUMO

BACKGROUND: Persistent hemolytic anemia and a lack of oral treatments are challenges for patients with paroxysmal nocturnal hemoglobinuria who have received anti-C5 therapy or have not received complement inhibitors. Iptacopan, a first-in-class oral factor B inhibitor, has been shown to improve hemoglobin levels in these patients. METHODS: In two phase 3 trials, we assessed iptacopan monotherapy over a 24-week period in patients with hemoglobin levels of less than 10 g per deciliter. In the first, anti-C5-treated patients were randomly assigned to switch to iptacopan or to continue anti-C5 therapy. In the second, single-group trial, patients who had not received complement inhibitors and who had lactate dehydrogenase (LDH) levels more than 1.5 times the upper limit of the normal range received iptacopan. The two primary end points in the first trial were an increase in the hemoglobin level of at least 2 g per deciliter from baseline and a hemoglobin level of at least 12 g per deciliter, each without red-cell transfusion; the primary end point for the second trial was an increase in hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. RESULTS: In the first trial, 51 of the 60 patients who received iptacopan had an increase in the hemoglobin level of at least 2 g per deciliter from baseline, and 42 had a hemoglobin level of at least 12 g per deciliter, each without transfusion; none of the 35 anti-C5-treated patients attained the end-point levels. In the second trial, 31 of 33 patients had an increase in the hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. In the first trial, 59 of the 62 patients who received iptacopan and 14 of the 35 anti-C5-treated patients did not require or receive transfusion; in the second trial, no patients required or received transfusion. Treatment with iptacopan increased hemoglobin levels, reduced fatigue, reduced reticulocyte and bilirubin levels, and resulted in mean LDH levels that were less than 1.5 times the upper limit of the normal range. Headache was the most frequent adverse event with iptacopan. CONCLUSIONS: Iptacopan treatment improved hematologic and clinical outcomes in anti-C5-treated patients with persistent anemia - in whom iptacopan showed superiority to anti-C5 therapy - and in patients who had not received complement inhibitors. (Funded by Novartis; APPLY-PNH ClinicalTrials.gov number, NCT04558918; APPOINT-PNH ClinicalTrials.gov number, NCT04820530.).


Assuntos
Anemia Hemolítica , Fator B do Complemento , Inativadores do Complemento , Hemoglobinas , Hemoglobinúria Paroxística , Humanos , Administração Oral , Anemia Hemolítica/complicações , Complemento C5/antagonistas & inibidores , Fator B do Complemento/antagonistas & inibidores , Inativadores do Complemento/administração & dosagem , Inativadores do Complemento/efeitos adversos , Inativadores do Complemento/uso terapêutico , Transfusão de Eritrócitos , Cefaleia/induzido quimicamente , Hemoglobinas/análise , Hemoglobinúria Paroxística/tratamento farmacológico , Hemoglobinúria Paroxística/etiologia , Ensaios Clínicos Fase III como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Asian J Pharm Sci ; 19(1): 100887, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38419762

RESUMO

Rheumatoid Arthritis (RA) is an autoimmune disorder that hinders the normal functioning of bones and joints and reduces the quality of human life. Every year, millions of people are diagnosed with RA worldwide, particularly among elderly individuals and women. Therefore, there is a global need to develop new biomaterials, medicines and therapeutic methods for treating RA. This will improve the Healthcare Access and Quality Index and also relieve administrative and financial burdens on healthcare service providers at a global scale. Hydrogels are soft and cross-linked polymeric materials that can store a chunk of fluids, drugs and biomolecules for hydration and therapeutic applications. Hydrogels are biocompatible and exhibit excellent mechanical properties, such as providing elastic cushions to articulating joints by mimicking the natural synovial fluid. Hence, hydrogels create a natural biological environment within the synovial cavity to reduce autoimmune reactions and friction. Hydrogels also lubricate the articulating joint surfaces to prevent degradation of synovial surfaces of bones and cartilage, thus exhibiting high potential for treating RA. This work reviews the progress in injectable and implantable hydrogels, synthesis methods, types of drugs, advantages and challenges. Additionally, it discusses the role of hydrogels in targeted drug delivery, mechanistic behaviour and tribological performance for RA treatment.

15.
Autism ; 28(9): 2267-2281, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38361371

RESUMO

LAY ABSTRACT: Rett syndrome often involves gastrointestinal symptoms and gut microbiota imbalances. We conducted a study to explore the feasibility of probiotic Lactobacillus plantarum PS128 and the impact on neurological functions in Rett syndrome. The results of our investigation demonstrated that the supplementation of probiotic L. plantarum PS128 was feasible and well tolerated, with 100% retention rate and 0% withdrawal rate. In addition, there was only one participant who had loose stool after taking L. plantarum PS128. Further, there was a tendency to enhance overall cognitive developmental level, as assessed using Mullen Scales of Early Learning. In addition, it significantly improved dystonia, as assessed using the Burke-Fahn-Marsden Movement Scale, in comparison with the placebo group. This study provides a strong foundation for future research and clinical trials exploring the potential of L. plantarum PS128 probiotics as a complementary therapy for individuals with Rett syndrome.


Assuntos
Lactobacillus plantarum , Probióticos , Síndrome de Rett , Humanos , Síndrome de Rett/terapia , Probióticos/uso terapêutico , Projetos Piloto , Feminino , Método Duplo-Cego , Criança , Pré-Escolar , Resultado do Tratamento , Masculino , Adolescente
16.
J Formos Med Assoc ; 123(7): 811-817, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38360490

RESUMO

BACKGROUND: The SARS-CoV-2 virus has been a global public health threat since December 2019. This study aims to investigate the neurological characteristics and risk factors of coronavirus disease 2019 (COVID-19) in Taiwanese children, using data from a collaborative registry. METHODS: A retrospective, cross-sectional, multi-center study was done using an online network of pediatric neurological COVID-19 cohort collaborative registry. RESULTS: A total of 11160 COVID-19-associated emergency department (ED) visits and 1079 hospitalizations were analyzed. Seizures were the most common specific neurological symptom, while encephalitis and acute disseminated encephalomyelitis (ADEM) was the most prevalent severe involvement. In ED patients with neurological manifestations, severe neurological diagnosis was associated with visual hallucination, seizure with/without fever, behavior change, decreased GCS, myoclonic jerk, decreased activity/fatigue, and lethargy. In hospitalized patients with neurological manifestations, severe neurological diagnosis was associated with behavior change, visual hallucination, decreased GCS, seizure with/without fever, myoclonic jerk, fatigue, and hypoglycemia at admission. Encephalitis/ADEM was the only risk factor for poor neurological outcomes at discharge in hospitalized patients. CONCLUSION: Neurological complications are common in pediatric COVID-19. Visual hallucination, seizure, behavior change, myoclonic jerk, decreased GCS, and hypoglycemia at admission are the most important warning signs of severe neurological involvement such as encephalitis/ADEM.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Taiwan/epidemiologia , COVID-19/complicações , COVID-19/epidemiologia , Estudos Transversais , Criança , Masculino , Feminino , Estudos Retrospectivos , Pré-Escolar , Adolescente , Lactente , Fatores de Risco , Doenças do Sistema Nervoso/etiologia , Hospitalização/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Convulsões/etiologia , Convulsões/epidemiologia , Sistema de Registros
17.
Acad Emerg Med ; 31(6): 538-546, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38415363

RESUMO

BACKGROUND: The emergency department (ED) is a demanding and time-pressured environment where doctors must navigate numerous team interactions. Conflicts between health care professionals frequently arise in these settings. We aim to synthesize the individual-, team-, and systemic-level factors that contribute to conflict between clinicians within the ED and explore strategies and opportunities for future research. METHODS: Online databases PubMed and Web of Science were systematically searched for relevant peer-reviewed journal articles in English with keywords relating to "conflict" and "emergency department," yielding a total of 29 articles. RESULTS: Narrative analysis showed that conflict often occurred during referrals or admissions from ED to inpatient or admitting units. Individual-level contributors to conflict include a lack of trust in ED workup and staff inexperience. Team-level contributors include perceptions of bias between groups, patient complexity, communication errors, and difference in practice. Systems-level contributors include high workload/time pressures, ambiguities around patient responsibility, power imbalances, and workplace culture. Among identified solutions to mitigate conflict are better communication training, standardizing admission guidelines, and improving interdepartmental relationships. CONCLUSIONS: In emergency medicine, conflict is common and occurs at multiple levels, reflecting the complex interface of tasks and relationships within ED.


Assuntos
Medicina de Emergência , Serviço Hospitalar de Emergência , Humanos , Relações Interprofissionais , Equipe de Assistência ao Paciente , Conflito Psicológico , Comunicação
18.
Light Sci Appl ; 13(1): 29, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267427

RESUMO

Bremsstrahlung-the spontaneous emission of broadband radiation from free electrons that are deflected by atomic nuclei-contributes to the majority of X-rays emitted from X-ray tubes and used in applications ranging from medical imaging to semiconductor chip inspection. Here, we show that the bremsstrahlung intensity can be enhanced significantly-by more than three orders of magnitude-through shaping the electron wavefunction to periodically overlap with atoms in crystalline materials. Furthermore, we show how to shape the bremsstrahlung X-ray emission pattern into arbitrary angular emission profiles for purposes such as unidirectionality and multi-directionality. Importantly, we find that these enhancements and shaped emission profiles cannot be attributed solely to the spatial overlap between the electron probability distribution and the atomic centers, as predicted by the paraxial and non-recoil theory for free electron light emission. Our work highlights an unprecedented regime of free electron light emission where electron waveshaping provides multi-dimensional control over practical radiation processes like bremsstrahlung. Our results pave the way towards greater versatility in table-top X-ray sources and improved fundamental understanding of quantum electron-light interactions.

19.
NPJ Precis Oncol ; 8(1): 20, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38273040

RESUMO

Utility of PI3Kα inhibitors like BYL719 is limited by the acquisition of genetic and non-genetic mechanisms of resistance which cause disease recurrence. Several combination therapies based on PI3K inhibition have been proposed, but a way to systematically prioritize them for breast cancer treatment is still missing. By integrating published and in-house studies, we have developed in silico models that quantitatively capture dynamics of PI3K signaling at the network-level under a BYL719-sensitive versus BYL719 resistant-cell state. Computational predictions show that signal rewiring to alternative components of the PI3K pathway promote resistance to BYL719 and identify PDK1 as the most effective co-target with PI3Kα rescuing sensitivity of resistant cells to BYL719. To explore whether PI3K pathway-independent mechanisms further contribute to BYL719 resistance, we performed phosphoproteomics and found that selection of high levels of the cell cycle regulator p21 unexpectedly promoted drug resistance in T47D cells. Functionally, high p21 levels favored repair of BYL719-induced DNA damage and bypass of the associated cellular senescence. Importantly, targeted inhibition of the check-point inhibitor CHK1 with MK-8776 effectively caused death of p21-high T47D cells, thus establishing a new vulnerability of BYL719-resistant breast cancer cells. Together, our integrated studies uncover hidden molecular mediators causing resistance to PI3Kα inhibition and provide a framework to prioritize combination therapies for PI3K-mutant breast cancer.

20.
BMJ Lead ; 8(1): 88-92, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-37491151

RESUMO

Servant leadership is an other-oriented approach to leadership with multiple positive outcomes. However, its influence in the context of medicine, particularly on healthcare leaders, is less clear. We conducted a rapid review to examine the impact of servant leadership in healthcare over the last decade. We included a total of 28 articles, 26 of which described beneficial organisational, relational and personal outcomes of servant leadership. However, most of these were either conceptual or opinion-based articles. Moreover, most quantitative studies were cross-sectional, precluding causal inferences. Our review demonstrates that the purported positive association between servant leadership and healthcare outcomes lacks a strong evidence base. We conclude by calling for more rigorous empirical research to examine the effects and potential challenges of implementing servant leadership in healthcare contexts.


Assuntos
Liderança , Medicina , Atenção à Saúde , Atitude , Instalações de Saúde
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