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1.
Chem Commun (Camb) ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39228333

RESUMO

Cyclic nucleoside phosphates have been shown previously to be adequately activated to oligomerise under dry conditions. Herein, it is demonstrated that 3',5'-cyclic adenosine monophosphate (3',5'-cAMP) and glycine when subjected to dehydration under alkaline conditions form phosphoramidate-linked conjugates. Solid-state reaction mechanisms investigated by DFT suggest why the reaction does not occur efficiently in the aqueous phase.

2.
Neurology ; 103(7): e209793, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39226519

RESUMO

BACKGROUND AND OBJECTIVES: Data on care home admission and survival rates of patients with syndromes associated with frontotemporal lobar degeneration (FTLD) are limited. However, their estimation is essential to plan trials and assess the efficacy of intervention. Population-based registers provide unique samples for this estimate. The aim of this study was to assess care home admission rate, survival rate, and their predictors in incident patients with FTLD-associated syndromes from the European FRONTIERS register-based study. METHODS: We conducted a prospective longitudinal multinational observational registry study, considering incident patients with FTLD-associated syndromes diagnosed between June 1, 2018, and May 31, 2019, and followed for up to 5 years till May 31, 2023. We enrolled patients fulfilling diagnosis of the behavioral variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), progressive supranuclear palsy (PSP) or corticobasal syndrome (CBS), and FTD with motor neuron disease (FTD-MND). Kaplan-Meier analysis and Cox multivariable regression models were used to assess care home admission and survival rates. The survival probability score (SPS) was computed based on independent predictors of survivorship. RESULTS: A total of 266 incident patients with FTLD were included (mean age ± SD = 66.7 ± 9.0; female = 41.4%). The median care home admission rate was 97 months (95% CIs 86-98) from disease onset and 57 months (95% CIs 56-58) from diagnosis. The median survival was 90 months (95% CIs 77-97) from disease onset and 49 months (95% CIs 44-58) from diagnosis. Survival from diagnosis was shorter in FTD-MND (hazard ratio [HR] 4.59, 95% CIs 2.49-8.76, p < 0.001) and PSP/CBS (HR 1.56, 95% CIs 1.01-2.42, p = 0.044) compared with bvFTD; no differences between PPA and bvFTD were found. The SPS proved high accuracy in predicting 1-year survival probability (area under the receiver operating characteristic curve = 0.789, 95% CIs 0.69-0.87), when defined by age, European area of residency, extrapyramidal symptoms, and MND at diagnosis. DISCUSSION: In FTLD-associated syndromes, survival rates differ according to clinical features and geography. The SPS was able to predict prognosis at individual patient level with an accuracy of ∼80% and may help to improve patient stratification in clinical trials. Future confirmatory studies considering different populations are needed.


Assuntos
Afasia Primária Progressiva , Degeneração Lobar Frontotemporal , Paralisia Supranuclear Progressiva , Humanos , Masculino , Idoso , Feminino , Europa (Continente)/epidemiologia , Pessoa de Meia-Idade , Degeneração Lobar Frontotemporal/mortalidade , Degeneração Lobar Frontotemporal/diagnóstico , Degeneração Lobar Frontotemporal/epidemiologia , Paralisia Supranuclear Progressiva/mortalidade , Paralisia Supranuclear Progressiva/terapia , Paralisia Supranuclear Progressiva/diagnóstico , Taxa de Sobrevida , Afasia Primária Progressiva/mortalidade , Afasia Primária Progressiva/terapia , Estudos Prospectivos , Estudos Longitudinais , Sistema de Registros , Demência Frontotemporal/mortalidade , Demência Frontotemporal/epidemiologia , Demência Frontotemporal/diagnóstico , Demência Frontotemporal/terapia , Casas de Saúde/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Idoso de 80 Anos ou mais , Doença dos Neurônios Motores/mortalidade , Doença dos Neurônios Motores/epidemiologia , Doença dos Neurônios Motores/terapia , Doenças dos Gânglios da Base/epidemiologia , Doenças dos Gânglios da Base/mortalidade
3.
J Neurol ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141064

RESUMO

Pathogenic variants in the Cu/Zn superoxide dismutase (SOD1) gene can be detected in approximately 2% of sporadic and 11% of familial amyotrophic lateral sclerosis (ALS) patients in Europe. We analyzed the clinical phenotypes of 83 SOD1-ALS patients focusing on patients carrying the most frequent (likely) pathogenic variants (R116G, D91A, L145F) in Germany. Moreover, we describe the effect of tofersen treatment on ten patients carrying these variants. R116G patients showed the most aggressive course of disease with a median survival of 22.0 months compared to 198.0 months in D91A and 87.0 months in L145F patients (HR 7.71, 95% CI 2.89-20.58 vs. D91A; p < 0.001 and HR 4.25, 95% CI 1.55-11.67 vs. L145F; p = 0.02). Moreover, R116G patients had the fastest median ALSFRS-R progression rate with 0.12 (IQR 0.07-0.20) points lost per month. Median diagnostic delay was 10.0 months (IQR 5.5-11.5) and therefore shorter compared to 57.5 months (IQR 14.0-83.0) in D91A (p < 0.001) and 21.5 months (IQR 5.8-38.8) in L145F (p = 0.21) carriers. As opposed to D91A carriers (50.0%), 96.2% of R116G (p < 0.001) and 100.0% of L145F (p = 0.04) patients reported a positive family history. During tofersen treatment, all patients showed a reduction of neurofilament light chain (NfL) serum levels, independent of the SOD1 variant. Patients with SOD1-ALS carrying R116G, D91A, or L145F variants show commonalities, but also differences in their clinical phenotype, including a faster progression rate with shorter survival in R116G, and a comparatively benign disease course in D91A carriers.

4.
J Clin Oncol ; : JCO2400081, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102622

RESUMO

PURPOSE: The EXTEND trial tested the hypothesis that adding comprehensive metastasis-directed therapy (MDT) to chemotherapy would improve progression-free survival (PFS) over chemotherapy alone among patients with oligometastatic pancreatic ductal adenocarcinoma (PDAC). METHODS: EXTEND (ClinicalTrials.gov identifier: NCT03599765) is a multicenter, phase II basket trial randomly assigning patients with ≤five metastases 1:1 to MDT plus systemic therapy versus systemic therapy. Disease progression was defined by radiologic criteria (RECIST v1.1), clinical progression, or death. The primary end point was PFS in the per-protocol population, evaluated after all patients achieved at least 6 months of follow-up. Exploratory end points included systemic immune response measures. RESULTS: Between March 19, 2019, and February 13, 2023, 41 patients were randomly assigned and 40 were eligible for the primary analysis of PFS (19 patients in the MDT arm; 21 patients in the control arm). At a median follow-up time of 17 months, the median PFS time was 10.3 months (95% CI, 4.6 to 14.0) in the MDT arm versus 2.5 months (95% CI, 1.7 to 5.1) in the control arm. PFS was significantly improved by the addition of MDT to systemic therapy (P = .030 for stratified log-rank test) with a hazard ratio of 0.43 (95% CI, 0.20 to 0.94). No grade ≥3 or greater adverse events related to MDT were observed. Systemic immune activation events were associated with MDT and correlated with improved PFS. CONCLUSION: This study supports the addition of MDT to systemic therapy for patients with oligometastatic PDAC. Induction of systemic immunity is a possible mechanism of benefit. These results warrant confirmatory trials to refine treatment strategy and provide external validation.

5.
Thorax ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39117421

RESUMO

INTRODUCTION: The pathogenesis of sarcoidosis involves tissue remodelling mediated by the accumulation of abnormal extracellular matrix, which is partly the result of an imbalance in collagen synthesis, cross-linking and degradation. During this process, collagen fragments or neoepitopes, are released into the circulation. The significance of these circulating collagen neoepitopes in sarcoidosis remains unknown. METHODS: We employed plasma samples from patients with sarcoidosis enrolled in A Case Control Etiologic Study of Sarcoidosis (ACCESS) and Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS), and healthy control patients recruited from the Yale community. Plasma concentrations of type III and VI collagen degradation (C3M and C6M) and formation (PRO-C3 and PRO-C6) were quantified via neoepitope-specific competitive ELISA, and statistical associations were sought with clinical phenotypes. RESULTS: Relative to healthy controls, the plasma of both sarcoidosis cohorts was enriched for C3M and C6M, irrespective of corticosteroid use and disease duration. While circulating collagen neoepitopes were independent of Scadding stage, there was a significant association between multiorgan disease and PRO-C3, PRO-C6 and C3M in the ACCESS cohort; PRO-C3 and C6M displayed this property in GRADS. These findings were unrelated to plasma levels of interleukin-4 (IL-4), IL-5, IL-6, IL-9, IL-10 and IL-13. Moreover, PRO-C3 was associated with dermatological disease in both cohorts. DISCUSSION: In two well-characterised sarcoidosis cohorts, we discovered that the plasma is enriched for neoepitopes of collagen degradation (C3M and C6M). In multiorgan disease, there was an association with circulating neoepitopes of type III formation (PRO-C3), perhaps mediated by dermatological sarcoidosis. Further investigation in this arena has the potential to foster new insights into the pathogenic mechanisms of this complex disease.

6.
Chem Sci ; 15(31): 12326-12335, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39118640

RESUMO

Multiheme cytochromes (MHCs) are the building blocks of highly conductive micrometre-long supramolecular wires found in so-called electrical bacteria. Recent studies have revealed that these proteins possess a long supramolecular array of closely packed heme cofactors along the main molecular axis alternating between perpendicular and stacking configurations (TST = T-shaped, stacked, T-shaped). While TST arrays have been identified as the likely electron conduit, the mechanisms of outstanding long-range charge transport observed in these structures remain unknown. Here we study charge transport on individual small tetraheme cytochromes (STCs) containing a single TST heme array. Individual STCs are trapped in a controllable nanoscale tunnelling gap. By modulating the tunnelling gap separation, we are able to selectively probe four different electron pathways involving 1, 2, 3 and 4 heme cofactors, respectively, leading to the determination of the electron tunnelling decay constant along the TST heme motif. Conductance calculations of selected single-STC junctions are in excellent agreement with experiments and suggest a mechanism of electron tunnelling with shallow length decay constant through an individual STC. These results demonstrate that an individual TST motif supporting electron tunnelling might contribute to a tunnelling-assisted charge transport diffusion mechanism in larger TST associations.

7.
Sci Immunol ; 9(98): eadk9872, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39121194

RESUMO

The Aedes aegypti mosquito is a vector of many infectious agents, including flaviviruses such as Zika virus. Components of mosquito saliva have pleomorphic effects on the vertebrate host to enhance blood feeding, and these changes also create a favorable niche for pathogen replication and dissemination. Here, we demonstrate that human CD47, which is known to be involved in various immune processes, interacts with a 34-kilodalton mosquito salivary protein named Nest1. Nest1 is up-regulated in blood-fed female A. aegypti and facilitates Zika virus dissemination in human skin explants. Nest1 has a stronger affinity for CD47 than its natural ligand, signal regulatory protein α, competing for binding at the same interface. The interaction between Nest1 with CD47 suppresses phagocytosis by human macrophages and inhibits proinflammatory responses by white blood cells, thereby suppressing antiviral responses in the skin. This interaction elucidates how an arthropod protein alters the human response to promote arbovirus infectivity.


Assuntos
Aedes , Pele , Zika virus , Aedes/imunologia , Aedes/virologia , Animais , Humanos , Pele/imunologia , Pele/virologia , Zika virus/imunologia , Zika virus/fisiologia , Feminino , Proteínas de Insetos/imunologia , Infecção por Zika virus/imunologia , Proteínas e Peptídeos Salivares/imunologia , Mosquitos Vetores/imunologia , Mosquitos Vetores/virologia , Antígeno CD47
8.
Cancer Rep (Hoboken) ; 7(8): e2162, 2024 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-39118243

RESUMO

BAKGROUND: It is important to understand the outcomes of adult acute lymphoblastic leukemia (ALL) patients at different facilities as treatment paradigms change. AIMS: Our primary objective was to determine adult ALL overall survival (OS) by facility volume and type. Secondary objectives included identifying sociodemographic factors that may have impacted outcomes and analyzing treatment patterns by facility volume and type. METHODS: This was a retrospective analysis of the National Cancer Database (NCDB) that included patients ≥40 years diagnosed with ALL between 2004 and 2016. RESULTS: A total of 14 593 patients were included in this study. Univariate OS was greatest at low volume (LV) and community programs (CPs) and the least at high volume (HV) and academic programs (AP). This difference was lost after multivariable Cox proportional hazards model analysis, which found no difference in survival by facility volume or type, however, survival was significantly influenced by age, race, Hispanic ethnicity, insurance, and residence location (p < 0.05). Patients treated at HV and APs compared to LV and CP received more anti-neoplastic directed therapy. CONCLUSION: Our results suggest treatment facility volume and type do not impact older adult ALL patient (≥40 years) survival, however confounding sociodemographic differences do impact survival outcomes, despite more aggressive and novel treatment approaches provided at HV and APs.


Assuntos
Bases de Dados Factuais , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Bases de Dados Factuais/estatística & dados numéricos , Adulto , Estados Unidos/epidemiologia , Taxa de Sobrevida , Hospitais com Alto Volume de Atendimentos/estatística & dados numéricos , Idoso de 80 Anos ou mais , Hospitais com Baixo Volume de Atendimentos/estatística & dados numéricos
10.
PLoS Genet ; 20(8): e1011360, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39172766

RESUMO

Secondary contact between closely related taxa represents a "moment of truth" for speciation-an opportunity to test the efficacy of reproductive isolation that evolved in allopatry and to identify the genetic, behavioral, and/or ecological barriers that separate species in sympatry. Sex chromosomes are known to rapidly accumulate differences between species, an effect that may be exacerbated for neo-sex chromosomes that are transitioning from autosomal to sex-specific inheritance. Here we report that, in the Solomon Islands, two closely related bird species in the honeyeater family-Myzomela cardinalis and Myzomela tristrami-carry neo-sex chromosomes and have come into recent secondary contact after ~1.1 my of geographic isolation. Hybrids of the two species were first observed in sympatry ~100 years ago. To determine the genetic consequences of hybridization, we use population genomic analyses of individuals sampled in allopatry and in sympatry to characterize gene flow in the contact zone. Using genome-wide estimates of diversity, differentiation, and divergence, we find that the degree and direction of introgression varies dramatically across the genome. For sympatric birds, autosomal introgression is bidirectional, with phenotypic hybrids and phenotypic parentals of both species showing admixed ancestry. In other regions of the genome, however, the story is different. While introgression on the Z/neo-Z-linked sequence is limited, introgression of W/neo-W regions and mitochondrial sequence (mtDNA) is highly asymmetric, moving only from the invading M. cardinalis to the resident M. tristrami. The recent hybridization between these species has thus enabled gene flow in some genomic regions but the interaction of admixture, asymmetric mate choice, and/or natural selection has led to the variation in the amount and direction of gene flow at sex-linked regions of the genome.


Assuntos
Fluxo Gênico , Introgressão Genética , Hibridização Genética , Isolamento Reprodutivo , Cromossomos Sexuais , Animais , Cromossomos Sexuais/genética , Especiação Genética , Simpatria , Masculino , Feminino , Aves/genética , Melanesia , Genética Populacional , Genoma/genética
11.
Adv Mater ; : e2408271, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177115

RESUMO

Radicals, with their unpaired electrons, exhibit unique chemical and physical properties that have long intrigued chemists. Despite early skepticism about their stability, the discovery of persistent radicals has opened new possibilities for molecular interactions. This review examines the mechanisms and applications of radically driven self-assembly, focusing on key motifs such as naphthalene diimides, tetrathiafulvalenes, and viologens, which serve as models for radical assembly. The potential of radical interactions in the development of artificial molecular machines (AMMs) are also discussed. These AMMs, powered by radical-radical interactions, represent significant advancements in non-equilibrium chemistry, mimicking the functionalities of biological systems. From molecular switches to ratchets and pumps, the versatility and unique properties of radically powered AMMs are highlighted. Additionally, the applications of radical assembly in materials science are explored, particularly in creating smart materials with redox-responsive properties. The review concludes by comparing AMMs to biological molecular machines, offering insights into future directions. This overview underscores the impact of radical chemistry on molecular assembly and its promising applications in both synthetic and biological systems.

12.
Ann Neurol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177232

RESUMO

OBJECTIVE: Neurofilament light chains (NfL) and phosphorylated neurofilament heavy chains (pNfH), established as diagnostic and prognostic biomarkers in hospital-based amyotrophic lateral sclerosis (ALS) cohorts, are now surrogate markers in clinical trials. This study extends their evaluation to a population level, with the aim of advancing their full establishment and assessing the transferability of biomarker findings from controlled cohorts to real-world ALS populations. METHODS: We measured serum NfL and pNfH levels in all ALS patients (n = 790) and general population controls (n = 570) with available baseline samples participating in the epidemiological ALS Registry Swabia, providing platform-specific (ELLA™) reference data and Z-scores for controls, as well as reference data, disease-specific Z-scores and longitudinal data in ALS. We evaluated the diagnostic and prognostic utility of neurofilaments and quantified the impact of ALS-related factors and non-ALS confounders. RESULTS: Neurofilaments showed high diagnostic and prognostic utility at the population level, with NfL superior to pNfH. The novel concept of a population-based ALS Z-score significantly improved the prognostic utility compared to absolute raw values. Both biomarkers increased more strongly with age in controls than in ALS, and age adjustment improved diagnostic accuracy. Our data show that disease progression rates, ALS phenotype, body mass index (BMI), and renal function need to be considered when interpreting neurofilament levels; longitudinal neurofilament levels were generally stable in individual patients, especially when adjusted for age and baseline levels. INTERPRETATION: Population-based assessment enhances the utility of particularly serum NfL as a diagnostic and prognostic biomarker in ALS and improves the translation of findings from controlled cohorts to real-world populations. ANN NEUROL 2024.

13.
Blood Adv ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167805

RESUMO

Since 2005 there has been steady decline in chronic graft-versus-host disease (cGVHD) at Fred Hutchinson Cancer Center (FHCC). To better understand this phenomenon, we studied the risk of cGVHD requiring systemic immunosuppression (cGVHD-IS) as a function of hematopoietic cell transplantation (HCT)-date in 3066 survivors from 2005 through 2019. Cox regression models were fit to assess associations of HCT-date (as a continuous linear variable) with cause-specific hazards of cGVHD, using unadjusted and adjusted models. Median follow-up for study subjects was 7.0 years (range, 1.0-17.2). Two-year probabilities of cGVHD-IS declined among all survivors from 45-52% (2005-2007) to approximately 40% (2008-2012) and then further to ~26% by 2017. A decline was also observed when the analysis was restricted to 502 pediatric survivors, with cGVHD-IS probabilities being <10% since 2013. Among 305 adult and pediatric survivors who were transplanted for nonmalignant diseases, cGVHD rates showed greater fluctuation but remained <20% after 2016. Each 5-year increase in HCT-date was associated with a 27% decrease in the cause-specific hazard of cGVHD (unadjusted hazard ratio [HR] 0.73; 95% confidence interval [CI] 0.68-0.78, p<.0001); the HR was 0.81 (95% CI 0.75-0.87, p<.0001) even after adjusting for various factors (age, donor/stem-cell source, race, sex, conditioning intensity, GVHD prophylaxis, among others) that could lead to cGVHD reduction. The decline in cGVHD was not fully explained by demographic shifts and greater use of HCT approaches generally associated with lower cGVHD rates. This observation underscores that single-cohort cGVHD-prevention studies should use contemporaneous and not historical controls for comparisons.

14.
Stroke ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39193713

RESUMO

BACKGROUND: Associations between magnetic resonance imaging markers of cerebral small vessel disease (CSVD) and dementia risk in older adults have been established, but it remains unclear how lifestyle factors, including psychosocial health, may modify this association. METHODS: Social support and social isolation were assessed among participants of the community-based ARIC (Atherosclerosis Risk in Communities) Study, via self-reported questionnaires (1990-1992). Following categorization of both factors, participants were classified as having strong or poor mid-life social relationships. At visit 5 (2011-2013), participants underwent 3T brain magnetic resonance imaging quantifying CSVD measures: white matter hyperintensity volume, microbleeds (subcortical), infarcts (lacunar), and white matter integrity (diffusion tensor imaging). Incident dementia cases were identified from the time of imaging through December 31, 2020 with ongoing surveillance. Associations between CSVD magnetic resonance imaging markers and incident dementia were evaluated using Cox proportional-hazard regressions adjusted for demographic and additional risk factors (from visit 2). Effect modification by mid-life social relationships was evaluated. RESULTS: Of the 1977 participants with magnetic resonance imaging, 1617 participants (60.7% women; 26.5% Black participants; mean age at visit 2, 55.4 years) were examined. In this sample, mid-life social relationships significantly modified the association between white matter hyperintensity volume and dementia risk (P interaction=0.001). Greater white matter hyperintensity volume was significantly associated with risk of dementia in all participants, yet, more substantially in those with poor (hazard ratio, 1.84 [95% CI, 1.49-2.27]) versus strong (hazard ratio, 1.26 [95% CI, 1.08-1.47]) mid-life social relationships. Although not statistically significant, subcortical microbleeds in participants with poor mid-life social relationships were associated with a greater risk of dementia, relative to those with strong social relationships, in whom subcortical microbleeds were no longer associated with elevated dementia risk. CONCLUSIONS: The elevated risk of dementia associated with CSVD may be reduced in participants with strong mid-life social relationships. Future studies evaluating psychosocial health through the life course and the mechanisms by which they modify the relationship between CSVD and dementia are needed.

15.
Curr Oncol ; 31(8): 4781-4794, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39195341

RESUMO

The United States Veterans Affairs (VA) Health Care System has a strong history of conducting impactful oncology randomized clinical trials (RCTs). We developed a phase II/III RCT to test the use of metastasis-directed therapy in Veterans with oligometastatic prostate cancer (OMPC)-the first VA RCT in OMPC that leverages novel imaging and advanced radiotherapy techniques. To accomplish this, we developed a clinical trial network to conduct the study. In this manuscript, we describe several challenges we encountered in study development/conduct and our strategies to address them, with the goal of helping investigators establish robust study networks to conduct clinical trials. In the study start-up, we encountered challenges in timely site activation, and leveraged project management to maximize efficiency. Additionally, there were several changes in the clinical paradigms in imaging and treatment that led to protocol amendments to ensure maximum equipoise, recruitment, and impact of the study. Specifically, we amended the trial to add de novo OMPC patients (from initially only recurrent OMPC) and expanded the study to allow up to 10 metastases (from initially five). Finally, in order to maintain local study team engagement, we developed initiatives to maximize collaboration and add value to the overall clinical program through study participation.


Assuntos
United States Department of Veterans Affairs , Humanos , Estados Unidos , Masculino , Oncologia/métodos , Neoplasias da Próstata/terapia , Veteranos , Ensaios Clínicos como Assunto
16.
Med Image Anal ; 97: 103277, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094461

RESUMO

Model quantization is a promising technique that can simultaneously compress and accelerate a deep neural network by limiting its computation bit-width, which plays a crucial role in the fast-growing AI industry. Despite model quantization's success in producing well-performing low-bit models, the quantization process itself can still be expensive, which may involve a long fine-tuning stage on a large, well-annotated training set. To make the quantization process more efficient in terms of both time and data requirements, this paper proposes a fast and accurate post-training quantization method, namely EfficientQ. We develop this new method with a layer-wise optimization strategy and leverage the powerful alternating direction method of multipliers (ADMM) algorithm to ensure fast convergence. Furthermore, a weight regularization scheme is incorporated to provide more guidance for the optimization of the discrete weights, and a self-adaptive attention mechanism is proposed to combat the class imbalance problem. Extensive comparison and ablation experiments are conducted on two publicly available medical image segmentation datasets, i.e., LiTS and BraTS2020, and the results demonstrate the superiority of the proposed method over various existing post-training quantization methods in terms of both accuracy and optimization speed. Remarkably, with EfficientQ, the quantization of a practical 3D UNet only requires less than 5 min on a single GPU and one data sample. The source code is available at https://github.com/rongzhao-zhang/EfficientQ.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos
17.
Ther Adv Neurol Disord ; 17: 17562864241263420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39206217

RESUMO

Background: This prospective study investigates the pattern of pareses in 5q-associated spinal muscular atrophy (SMA) to identify disease-specific characteristics and potential differences from amyotrophic lateral sclerosis (ALS) and spinobulbar muscular atrophy (SBMA). Detailed knowledge about pareses patterns in SMA facilitates differential diagnosis and supports therapeutic monitoring. Methods: Between January 2021, and June 2021, 66 SMA patients (59.1% male, aged 33.6 ± 15.2 years) were included in the study. Most patients had SMA type II (n = 28) or SMA type III (n = 28), seven patients had SMA type I, and three patients had SMA type IV. We analyzed the pattern of pareses using the UK Medical Research Council (MRC) scoring system. Results: In both, upper and lower limbs muscle weakness was less pronounced in distal (upper limbs: MRC median 3.0 (interquartile range 1.5-3.5); lower limbs: 1.5 (0.5-3.0)) compared to proximal muscle groups (upper limbs: 2.0 (1.5-2.6); p < 0.001; lower limbs: 0.5 (0.5-1.5); p < 0.001). Thenar muscles were stronger than other small hand muscles (3.0 (2.0-3.5) vs 3.0 (1.5-3.5); p = 0.004). Muscles had more strength in upper (2.3 (1.5-3.1)) compared to lower limbs (1.1 (0.5-2.3); p < 0.001) and in flexors compared to extensors. Conclusion: We identified a specific pattern of muscle paresis in SMA which is different from the pattern of paresis in ALS and SBMA. As a rule of thumb, the pattern of pareses is similar, but not identical to ALS in distal, but different in proximal muscle groups.

18.
Acta Parasitol ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217274

RESUMO

INTRODUCTION: Soil-transmitted helminth (STH) is a group of helminths that are considered to be neglected tropical diseases (NTDs) and, globally, affect more than 1.5 to 2.6 million people yearly. Depending on the species, they can be acquired by ingesting embryonated eggs from contaminated matter or by skin penetration. Most species of STH are found in the tropics, such as the Philippines. Despite the Mass Drug Administration (MDA), the cases of STH infection continue to rise in the country. Surveys from the Research Institute of Tropical Medicine (RITM) indicate that a high prevalence of STH (Ascaris lumbricoides, Trichuris trichiura, and Necator americanus) was primarily observed in the provinces of the country, such as in Camarines Sur. OBJECTIVES: To correlate remote sensing covariates such as Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built-up Index (NDBI) - to STH-infected cases of the 37 municipalities of Camarines Sur. METHODOLOGY: The available public health record of STH cases from 2015 to 2019 were calculated using the Quantum Geographic Information System (QGIS)and correlated using Pearson Correlation Coefficient. RESULTS: The results showed that infection was higher in children than adults, and A. lumbricoides caused 60% of infection. No correlation of indices with infection cases during 2015 and 2017 was observed; however, 2019 showed a moderate strength (p = 0.037) in correlation. CONCLUSION: This indicates that infection relied not mainly on vegetation and urbanization but on additional environmental factors and non-environmental variables.

19.
PM R ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995022

RESUMO

BACKGROUND: Muscle weakness is common and significantly affects persons with multiple sclerosis (PwMS), with dysfunction in upper limb (UL) muscle groups occurring in approximately 60% of PwMS. OBJECTIVE: To develop gender-specific regression-based prediction equations, with 95% confidence intervals for maximal bilateral UL isometric strength (shoulder abduction and adduction, wrist flexion and extension) and hand grip strength in PwMS. DESIGN: Cross-sectional study. SETTING: Comprehensive MS center. PARTICIPANTS: 256 PwMS. INTERVENTIONS: Not Applicable. MAIN OUTCOME MEASURES: Shoulder abduction and adduction and wrist flexion and extension isometric strength (Biodex System 4 Pro Dynamometer) and hand grip strength (Jamar handheld dynamometer) were measured. Disease characteristics (disability and disease duration) and demographics (age, height, and weight) were collected. Regression-based predictive equations were generated for the UL muscle groups for each gender and limb, using age, height, weight, disability, and disease duration as covariates. Variables were compared between genders using the Mann-Whitney U test. Maximal voluntary contraction (MVC) reference values (mean ± SD) were reported based on age (<30, 30-39, 40-49, 50-59, 60-69 years) and disability (mild, moderate, severe ambulant, and severe nonambulant) for each gender and limb. RESULTS: Regression-based equations were developed for both genders' strongest and weakest limb, accounting for age, height, weight, disability, and disease duration. MVC was higher in men than women (p < .001) in all muscle groups. Overall, MVC was significantly related to age in 14, height in 5, weight in 6, disability in 14, and disease duration in none of the 20 models. CONCLUSION: This is the first study to provide regression-based prediction equations for strongest and weakest MVC of UL muscle groups and demonstrated an inverse relationship between MVC with disability and age. Regression-based reference strength values can help clinicians understand muscular strength along a spectrum of PwMS and can aid in goal setting and education for realistic outcomes.

20.
Bull Math Biol ; 86(8): 101, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970749

RESUMO

We establish a general framework using a diffusion approximation to simulate forward-in-time state counts or frequencies for cladogenetic state-dependent speciation-extinction (ClaSSE) models. We apply the framework to various two- and three-region geographic-state speciation-extinction (GeoSSE) models. We show that the species range state dynamics simulated under tree-based and diffusion-based processes are comparable. We derive a method to infer rate parameters that are compatible with given observed stationary state frequencies and obtain an analytical result to compute stationary state frequencies for a given set of rate parameters. We also describe a procedure to find the time to reach the stationary frequencies of a ClaSSE model using our diffusion-based approach, which we demonstrate using a worked example for a two-region GeoSSE model. Finally, we discuss how the diffusion framework can be applied to formalize relationships between evolutionary patterns and processes under state-dependent diversification scenarios.


Assuntos
Simulação por Computador , Extinção Biológica , Especiação Genética , Conceitos Matemáticos , Modelos Biológicos , Filogenia , Animais , Modelos Genéticos , Evolução Biológica , Dinâmica Populacional/estatística & dados numéricos
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