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2.
BMJ Open ; 14(7): e081121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013654

RESUMEN

INTRODUCTION: Even with recent treatment advances, type 2 diabetes (T2D) remains poorly controlled for many patients, despite the best efforts to adhere to therapies and lifestyle modifications. Although estimates vary, studies indicate that in >10% of individuals with difficult-to-control T2D, hypercortisolism may be an underlying contributing cause. To better understand the prevalence of hypercortisolism and the impact of its treatment on T2D and associated comorbidities, we describe the two-part Hyper c ortisolism in P at ients with Difficult to Control Type 2 Di a betes Despite Receiving Standard-of-Care Therapies: Preva l ence and Treatment with Korl y m® (Mifepri st one) (CATALYST) trial. METHODS AND ANALYSIS: In part 1, approximately 1000 participants with difficult-to-control T2D (haemoglobin A1c (HbA1c) 7.5%-11.5% despite multiple therapies) are screened with a 1 mg dexamethasone suppression test (DST). Those with post-DST cortisol >1.8 µg/dL and dexamethasone level ≥140 ng/dL are identified to have hypercortisolism (part 1 primary endpoint), have morning adrenocorticotropic hormone (ACTH) and dehydroepiandrosterone sulfate (DHEAS) measured and undergo a non-contrast adrenal CT scan. Those requiring evaluation for elevated ACTH are referred for care outside the study; those with ACTH and DHEAS in the range may advance to part 2, a randomised, double-blind, placebo-controlled trial to evaluate the impact of treating hypercortisolism with the competitive glucocorticoid receptor antagonist mifepristone (Korlym®). Participants are randomised 2:1 to mifepristone or placebo for 24 weeks, stratified by the presence/absence of an abnormal adrenal CT scan. Mifepristone is dosed at 300 mg once daily for 4 weeks, then 600 mg daily based on tolerability and clinical improvement, with an option to increase to 900 mg. The primary endpoint of part 2 assesses changes in HbA1c in participants with hypercortisolism with or without abnormal adrenal CT scan. Secondary endpoints include changes in antidiabetes medications, cortisol-related comorbidities and quality of life. ETHICS AND DISSEMINATION: The study has been approved by Cleveland Clinic IRB (Cleveland, Ohio, USA) and Advarra IRB (Columbia, Maryland, USA). Findings will be presented at scientific meetings and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05772169.


Asunto(s)
Síndrome de Cushing , Diabetes Mellitus Tipo 2 , Mifepristona , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Síndrome de Cushing/tratamiento farmacológico , Estudios Prospectivos , Mifepristona/uso terapéutico , Prevalencia , Femenino , Masculino , Antagonistas de Hormonas/uso terapéutico , Estudios Multicéntricos como Asunto , Persona de Mediana Edad , Adulto , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Hidrocortisona/sangre , Método Doble Ciego
3.
Nat Med ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914124

RESUMEN

People with type-2-diabetes (T2D) and chronic kidney disease (CKD), have a high risk for kidney failure and cardiovascular (CV) complications. Glucagon-like-peptide-1 receptor agonists (GLP-1 RA) and sodium-glucose co-transporter-2 inhibitors (SGLT2i) independently reduce cardiovascular and kidney events. The effect of combining both is unclear. FLOW trial participants with T2D and CKD were stratified by baseline SGLT2i use (N = 550) or no use (N = 2,983) and randomized to semaglutide/placebo. The primary outcome was a composite of kidney failure, ≥50% eGFR reduction, kidney or cardiovascular death. The risk of the primary outcome was 24% lower in all participants treated with semaglutide vs placebo (95% confidence interval [CI] 34%, 12%). The primary outcome occurred in 41/277 (semaglutide) versus 38/273 (placebo) participants on SGLT2i at baseline (HR 1.07; 95% CI 0.69, 1.67; P=0.755), and in 290/1,490 versus 372/1,493 participants not taking SGLT2i at baseline (HR 0.73; 0.63, 0.85; P<0.001; P-interaction 0.109). Three confirmatory secondary outcomes were predefined. Treatment differences favoring semaglutide for total eGFR slope (ml/min/1.73m2/year) were 0.75 (-0.01, 1.5) in the SGLT2i subgroup and 1.25 (0.91, 1.58) in non-SGLT2i-subgroup, P-interaction 0.237. Semaglutide benefits on major cardiovascular events and all-cause death were similar regardless of SGLT2i use (P-interaction 0.741 and 0.901, respectively). The benefits of semaglutide in reducing kidney outcomes were consistent in participants with/without baseline SGLT2i use; power was limited to detect smaller but clinically relevant effects. ClinicalTrials.gov identifier: NCT03819153 .

4.
Clin Trials ; : 17407745241244788, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618711

RESUMEN

Randomization and blinding are regarded as the most important tools to help reduce bias in clinical trial designs. Randomization is used to help guarantee that treatment arms differ systematically only by treatment assignment at baseline, and blinding is used to ensure that differences in endpoint evaluation and clinical decision-making during the trial arise only from the treatment received and not, for example, the expectation or desires of the people involved. However, given that there are times when it is not feasible or ethical to conduct fully blinded trials, we discuss what can be done to improve a trial, including conducting the trial as if it were a fully blinded trial and maintaining confidentiality of ongoing study results. In this article, we review how best to design, conduct, and analyze open-label trials to ensure the highest level of study integrity and the reliability of the study conclusions.

5.
Am J Med Sci ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38636653

RESUMEN

Blood tests are vital to prevention, diagnosis, and management of chronic diseases. Despite this, it can be challenging to construct a comprehensive view of the clinical importance of blood testing because relevant literature is typically fragmented across different disease areas and patient populations. This lack of collated evidence can also make it difficult for primary care providers to adhere to best practices for blood testing across different diseases and guidelines. Thus, this review article synthesizes the recommendations for, and importance of, blood testing across several common chronic conditions encountered in primary care and internal medicine, including cardiovascular diseases, diabetes mellitus, chronic kidney disease, vitamin D deficiency, iron deficiency, and rheumatoid arthritis. Future research is needed to continue improving chronic disease management through clearer dissemination and awareness of clinical guidelines among providers, and better access to blood testing for patients (e.g., via pre-visit laboratory testing).

6.
Am J Respir Crit Care Med ; 209(6): 647-669, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38174955

RESUMEN

Background: Idiopathic pulmonary fibrosis (IPF) carries significant mortality and unpredictable progression, with limited therapeutic options. Designing trials with patient-meaningful endpoints, enhancing the reliability and interpretability of results, and streamlining the regulatory approval process are of critical importance to advancing clinical care in IPF. Methods: A landmark in-person symposium in June 2023 assembled 43 participants from the US and internationally, including patients with IPF, investigators, and regulatory representatives, to discuss the immediate future of IPF clinical trial endpoints. Patient advocates were central to discussions, which evaluated endpoints according to regulatory standards and the FDA's 'feels, functions, survives' criteria. Results: Three themes emerged: 1) consensus on endpoints mirroring the lived experiences of patients with IPF; 2) consideration of replacing forced vital capacity (FVC) as the primary endpoint, potentially by composite endpoints that include 'feels, functions, survives' measures or FVC as components; 3) support for simplified, user-friendly patient-reported outcomes (PROs) as either components of primary composite endpoints or key secondary endpoints, supplemented by functional tests as secondary endpoints and novel biomarkers as supportive measures (FDA Guidance for Industry (Multiple Endpoints in Clinical Trials) available at: https://www.fda.gov/media/162416/download). Conclusions: This report, detailing the proceedings of this pivotal symposium, suggests a potential turning point in designing future IPF clinical trials more attuned to outcomes meaningful to patients, and documents the collective agreement across multidisciplinary stakeholders on the importance of anchoring IPF trial endpoints on real patient experiences-namely, how they feel, function, and survive. There is considerable optimism that clinical care in IPF will progress through trials focused on patient-centric insights, ultimately guiding transformative treatment strategies to enhance patients' quality of life and survival.


Asunto(s)
Fibrosis Pulmonar Idiopática , Defensa del Paciente , Humanos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , National Institutes of Health (U.S.) , Calidad de Vida , Reproducibilidad de los Resultados , Estados Unidos , Capacidad Vital , Ensayos Clínicos como Asunto
7.
PLoS One ; 18(10): e0290181, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37906582

RESUMEN

Settlement crises in ancient cultures of Western Asia are commonly thought to be caused by climatic events such as severe droughts. However, the insufficient climate proxy situation in this region challenges the inference of clear relationships between climate and settlement dynamics. We investigate the Holocene climatic changes on the Varamin Plain in the context of the climatic history of Western Central Asia by using a transient comprehensive Earth System Model simulation (8 ka BP to pre-industrial), a high-resolution regional snapshot simulation and a synthesis of pollen-based climate reconstructions. In line with the reconstructions, the models reveal only slightly varying mean climatic conditions on the Varamin Plain but indicate substantial changes in seasonality during the Holocene. Increased precipitation during spring, combined with lower temperature and potentially stronger snow accumulation on the upstream Alborz mountains may have led to an increased water supply on the alluvial fan during the vegetation period and thus to more favourable conditions for agricultural production during the Mid-Holocene compared to modern times. According to the model, dry periods on the Central Iranian Plateau are related to particularly weak Westerly winds, fostering the subsidence in the mid-troposphere and hampering precipitation over the region. The model reveals that dry periods have spatially heterogenous manifestations, thus explaining why they do not appear in all proxy records in the wider study region. In fact, the climatic signal may depend on local environmental conditions. The interaction of the topography with the atmospheric circulation leads to additional spatial heterogeneity. Although our results provide several indications for a connection between climate and settlement dynamics, the small overall changes in moisture call into question whether climate is the main driver for settlement discontinuities on the Central Iranian Plateau. To shed further light on this issue, more high-resolution long-term proxy records are needed.


Asunto(s)
Clima , Viento , Irán , Estaciones del Año , Temperatura
10.
Microsc Microanal ; 29(Supplement_1): 1390-1391, 2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37613580
12.
Nanomaterials (Basel) ; 13(15)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37570584

RESUMEN

The nonlinear optical (NLO) response of photonic materials plays an important role in the understanding of light-matter interaction as well as pointing out a diversity of photonic and optoelectronic applications. Among the recently studied materials, 2D-LTMDs (bi-dimensional layered transition metal dichalcogenides) have appeared as a beyond-graphene nanomaterial with semiconducting and metallic optical properties. In this article, we review most of our work in studies of the NLO response of a series of 2D-LTMDs nanomaterials in suspension, using six different NLO techniques, namely hyper Rayleigh scattering, Z-scan, photoacoustic Z-scan, optical Kerr gate, and spatial self-phase modulation, besides the Fourier transform nonlinear optics technique, to infer the nonlinear optical response of semiconducting MoS2, MoSe2, MoTe2, WS2, semimetallic WTe2, ZrTe2, and metallic NbS2 and NbSe2. The nonlinear optical response from a thermal to non-thermal origin was studied, and the nonlinear refraction index and nonlinear absorption coefficient, where present, were measured. Theoretical support was given to explain the origin of the nonlinear responses, which is very dependent on the spectro-temporal regime of the optical source employed in the studies.

13.
Opt Lett ; 48(9): 2297-2300, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37126258

RESUMEN

By employing the optical Kerr gate technique at 800 nm with 180 fs pulses at 76 MHz, we evaluated the third-order nonlinear optical response of two-dimensional (2D) semiconducting MoS2, semimetallic ZrTe2, and metallic NbS2 and NbSe2. The modulus of the nonlinear refractive index was measured to range from 8.6 × 10-19 m2/W to 5.3 × 10-18 m2/W, with all materials' response time limited by the pulse duration. The physical mechanism to explain the ultrafast response time's origin considers the nature of the 2D material, as will be discussed.

14.
J Clin Invest ; 133(12)2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37071474

RESUMEN

BACKGROUNDThere is increasing evidence, in transgenic mice and in vitro, that inhibitory killer cell immunoglobulin-like receptors (iKIRs) can modulate T cell responses. Furthermore, we have previously shown that iKIRs are an important determinant of T cell-mediated control of chronic viral infection and that these results are consistent with an increase in the CD8+ T cell lifespan due to iKIR-ligand interactions. Here, we tested this prediction and investigated whether iKIRs affect T cell lifespan in humans in vivo.METHODSWe used stable isotope labeling with deuterated water to quantify memory CD8+ T cell survival in healthy individuals and patients with chronic viral infections.RESULTSWe showed that an individual's iKIR-ligand genotype was a significant determinant of CD8+ T cell lifespan: in individuals with 2 iKIR-ligand gene pairs, memory CD8+ T cells survived, on average, for 125 days; in individuals with 4 iKIR-ligand gene pairs, the memory CD8+ T cell lifespan doubled to 250 days. Additionally, we showed that this survival advantage was independent of iKIR expression by the T cell of interest and, further, that the iKIR-ligand genotype altered the CD8+ and CD4+ T cell immune aging phenotype.CONCLUSIONSTogether, these data reveal an unexpectedly large effect of iKIR genotype on T cell survival.FUNDINGWellcome Trust; Medical Research Council; EU Horizon 2020; EU FP7; Leukemia and Lymphoma Research; National Institute of Health Research (NIHR) Imperial Biomedical Research Centre; Imperial College Research Fellowship; National Institutes of Health; Jefferiss Trust.


Asunto(s)
Células Asesinas Naturales , Longevidad , Estados Unidos , Ratones , Animales , Humanos , Ligandos , Receptores KIR/genética , Receptores KIR/metabolismo , Linfocitos T CD8-positivos/metabolismo
15.
Respir Res ; 24(1): 38, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36726148

RESUMEN

BACKGROUND: The association between genetic variants on the X chromosome to risk of COPD has not been fully explored. We hypothesize that the X chromosome harbors variants important in determining risk of COPD related phenotypes and may drive sex differences in COPD manifestations. METHODS: Using X chromosome data from three COPD-enriched cohorts of adult smokers, we performed X chromosome specific quality control, imputation, and testing for association with COPD case-control status, lung function, and quantitative emphysema. Analyses were performed among all subjects, then stratified by sex, and subsequently combined in meta-analyses. RESULTS: Among 10,193 subjects of non-Hispanic white or European ancestry, a variant near TMSB4X, rs5979771, reached genome-wide significance for association with lung function measured by FEV1/FVC ([Formula: see text] 0.020, SE 0.004, p 4.97 × 10-08), with suggestive evidence of association with FEV1 ([Formula: see text] 0.092, SE 0.018, p 3.40 × 10-07). Sex-stratified analyses revealed X chromosome variants that were differentially trending in one sex, with significantly different effect sizes or directions. CONCLUSIONS: This investigation identified loci influencing lung function, COPD, and emphysema in a comprehensive genetic association meta-analysis of X chromosome genetic markers from multiple COPD-related datasets. Sex differences play an important role in the pathobiology of complex lung disease, including X chromosome variants that demonstrate differential effects by sex and variants that may be relevant through escape from X chromosome inactivation. Comprehensive interrogation of the X chromosome to better understand genetic control of COPD and lung function is important to further understanding of disease pathology. Trial registration Genetic Epidemiology of COPD Study (COPDGene) is registered at ClinicalTrials.gov, NCT00608764 (Active since January 28, 2008). Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints Study (ECLIPSE), GlaxoSmithKline study code SCO104960, is registered at ClinicalTrials.gov, NCT00292552 (Active since February 16, 2006). Genetics of COPD in Norway Study (GenKOLS) holds GlaxoSmithKline study code RES11080, Genetics of Chronic Obstructive Lung Disease.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Femenino , Masculino , Humanos , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/genética , Fenotipo , Cromosoma X
16.
NPJ 2D Mater Appl ; 7(1): 12, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38665486

RESUMEN

The development of high-precision large-area optical coatings and devices comprising low-dimensional materials hinges on scalable solution-based manufacturability with control over exfoliation procedure-dependent effects. As such, it is critical to understand the influence of technique-induced transition metal dichalcogenide (TMDC) optical properties that impact the design, performance, and integration of advanced optical coatings and devices. Here, we examine the optical properties of semiconducting MoS2 films from the exfoliation formulations of four prominent approaches: solvent-mediated exfoliation, chemical exfoliation with phase reconversion, redox exfoliation, and native redox exfoliation. The resulting MoS2 films exhibit distinct refractive indices (n), extinction coefficients (k), dielectric functions (ε1 and ε2), and absorption coefficients (α). For example, a large index contrast of Δn ≈ 2.3 is observed. These exfoliation procedures and related chemistries produce different exfoliated flake dimensions, chemical impurities, carrier doping, and lattice strain that influence the resulting optical properties. First-principles calculations further confirm the impact of lattice defects and doping characteristics on MoS2 optical properties. Overall, incomplete phase reconfiguration (from 1T to mixed crystalline 2H and amorphous phases), lattice vacancies, intraflake strain, and Mo oxidation largely contribute to the observed differences in the reported MoS2 optical properties. These findings highlight the need for controlled technique-induced effects as well as the opportunity for continued development of, and improvement to, liquid phase exfoliation methodologies. Such chemical and processing-induced effects present compelling routes to engineer exfoliated TMDC optical properties toward the development of next-generation high-performance mirrors, narrow bandpass filters, and wavelength-tailored absorbers.

17.
J Phys Chem Lett ; 13(25): 5808-5814, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35726902

RESUMEN

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) exhibit compelling dimension-dependent exciton-dominated optical behavior influenced by thickness and lateral quantum confinement effects. Thickness quantum confinement effects have been observed; however, experimental optical property assessment of nanoscale lateral dimension monolayer TMDCs is lacking. Here, we employ ex situ spectroscopic ellipsometry to evaluate laterally coalescing monolayer metalorganic chemical vapor deposited MoS2. A multisample analysis is used to constrain Bruggeman and Maxwell-Garnett effective medium approximations and the effective dielectric functions are derived for laterally coalesced and uncoalesced MoS2 films (∼10-94% surface coverage for ∼10-140 nm lateral grain sizes). This analysis demonstrates the ability to probe MoS2 optical exciton behavior at growth-relevant grain sizes in relation to chemical vapor nucleation density, ripening, and lateral growth conditions. Our analysis is pertinent toward expected in situ epitaxial 2D TMDC film growth metrology to enable the facile development of monolayer films with targeted process-dependent optical properties.

18.
Appl Opt ; 60(25): G232-G242, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34613214

RESUMEN

Although there has been progress in studying the electronic and optical properties of monolayer and near-monolayer (two-dimensional, 2D) MoS2 upon adatom adsorption and intercalation, understanding the underlying atomic-level behavior is lacking, particularly as related to the optical response. Alkali atom intercalation in 2D transition metal dichalcogenides (TMDs) is relevant to chemical exfoliation methods that are expected to enable large scale production. In this work, focusing on prototypical 2D MoS2, the adsorption and intercalation of Li, Na, K, and Ca adatoms were investigated for the 2H, 1T, and 1T' phases of the TMD by the first principles density functional theory in comparison to experimental characterization of 2H and 1T 2D MoS2 films. Our electronic structure calculations demonstrate significant charge transfer, influencing work function reductions of 1-1.5 eV. Furthermore, electrical conductivity calculations confirm the semiconducting versus metallic behavior. Calculations of the optical spectra, including excitonic effects using a many-body theoretical approach, indicate enhancement of the optical transmission upon phase change. Encouragingly, this is corroborated, in part, by the experimental measurements for the 2H and 1T phases having semiconducting and metallic behavior, respectively, thus motivating further experimental exploration. Overall, our calculations emphasize the potential impact of synthesis-relevant adatom incorporation in 2D MoS2 on the electronic and optical responses that comprise important considerations toward the development of devices such as photodetectors or the miniaturization of electroabsorption modulator components.

20.
Endocr Pract ; 27(12): 1189-1192, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34265454

RESUMEN

OBJECTIVE: Hypophosphatasia (HPP) is an inherited disease resulting from loss-of-function mutations in the ALPL gene encoding tissue-nonspecific alkaline phosphatase. The presentation and severity of the disease are highly variable, ranging from perinatal onset with high mortality rates to adult identification with low mortality rates and symptoms ranging from minimal to severe. Moderate forms of HPP typically manifest during middle age and are often undiagnosed. The objective of this study was to determine the occurrence and burden of HPP in an ambulatory care endocrinology practice. METHODS: Potential subjects were identified with a computerized text search of patient electronic medical records. Search terms included serum alkaline phosphatase (ALP) levels of ≤40 U/L. Records of patients with at least 2 low ALP levels were reviewed manually to identify potential patients with a history consistent with hypophosphatasia. RESULTS: In total, 315 patients with ALP levels ≤40 U/L were identified from an estimated 20 000 patient records. Fifty-six patients with a single low level were excluded from further review. The remaining 259 patients were reviewed, 10 of whom had histories consistent with HPP. None of the identified 10 patients was currently being treated or had previously been treated for HPP. Information about these patients was shared with their respective providers, along with the recommendation to proceed with further evaluation to confirm the diagnosis of HPP. CONCLUSION: Hypophosphatasia is an uncommon condition with variable presentation, often resulting in a missed diagnosis. Surveillance of practices by identifying patients with low ALP levels is a rational screening approach to identifying potential patients with HPP.


Asunto(s)
Hipofosfatasia , Adulto , Fosfatasa Alcalina/genética , Atención Ambulatoria , Humanos , Hipofosfatasia/diagnóstico , Hipofosfatasia/epidemiología , Hipofosfatasia/genética , Persona de Mediana Edad , Mutación
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