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1.
JBMR Plus ; 8(9): ziae093, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39108360

RESUMEN

Myeloma bone disease (MBD) affects ~90% of multiple myeloma patients, but current treatment options are suboptimal. Therefore, to successfully develop new therapies or optimize current ones, we must improve our fundamental knowledge of how myeloma affects bone microstructure and function. Here, we have investigated the osteocyte lacuno-canalicular network (LCN) in MBD, as bone porosity affects bone quality and resilience. We used the syngeneic 5TGM1-C57BL-Kalwrij and the xenograft U266-NSG models at end stage and compared them to healthy controls (naïve). Micro-computed tomography (µCT) and histomorphometry indicated the 5TGM1 and U266 models developed mild and extensive MBD, respectively, with the U266 model producing large osteolytic lesions. High-resolution synchrotron micro-CT (SR-µCT) revealed significant osteocyte lacunae changes in U266 bones but not 5TGM1, with a reduction in lacunae number and sphericity, and an increase in lacunae volume compared with naïve. Canalicular length, visualized using histological Ploton silver staining, appeared significantly shorter in 5TGM1 and U266 bones compared with naïve. Canalicular area as a proportion of the bone was also decreased by 24.2% in the U266 model. We observed significant upregulation of genes implicated in peri-lacunar remodeling (PLR), but immunohistochemistry confirmed that the osteocyte-specific protein sclerostin, a known driver of PLR, was unchanged between MBD and naïve bones. In summary, we have demonstrated evidence of PLR and altered organization of the osteocyte LCN in MBD mouse models. The next step would be to further understand the drivers and implications of PLR in MBD, and whether treatments to manipulate PLR and the LCN may improve patient outcomes.

3.
Inorg Chem ; 63(21): 9801-9808, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38743640

RESUMEN

Enzyme immobilization within metal-organic frameworks (MOFs) is a promising solution to avoid denaturation and thereby utilize the desirable properties of enzymes outside of their native environments. The biomimetic mineralization strategy employs biomacromolecules as nucleation agents to promote the crystallization of MOFs in water at room temperature, thus overcoming pore size limitations presented by traditional postassembly encapsulation. Most biomimetic crystallization studies reported to date have employed zeolitic imidazole frameworks (ZIFs). Herein, we expand the library of MOFs suitable for biomimetic mineralization to include zinc(II) MOFs incorporating functionalized terephthalic acid linkers and study the catalytic performance of the enzyme@MOFs. Amine functionalization of terephthalic acids is shown to accelerate the formation of crystalline MOFs enabling new enzyme@MOFs to be synthesized. The structure and morphology of the enzyme@MOFs were characterized by PXRD, FTIR, and SEM-EDX, and the catalytic potential was evaluated. Increasing the linker length while retaining the amino moiety gave rise to a family of linkers; however, MOFs generated with the 2,2'-aminoterephthalic acid linker displayed the best catalytic performance. Our data also illustrate that the pH of the reaction mixture affects the crystal structure of the MOF and that this structural transformation impacts the catalytic performance of the enzyme@MOF.


Asunto(s)
Ácidos Carboxílicos , Cristalización , Estructuras Metalorgánicas , Temperatura , Agua , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/síntesis química , Ácidos Carboxílicos/química , Agua/química , Ácidos Ftálicos/química , Materiales Biomiméticos/química , Materiales Biomiméticos/síntesis química , Estructura Molecular , Zinc/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Aminas/química , Catálisis
4.
J Phys Chem B ; 128(15): 3585-3597, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38593280

RESUMEN

Super-resolution and single-molecule microscopies have been increasingly applied to complex biological systems. A major challenge of these approaches is that fluorescent puncta must be detected in the low signal, high noise, heterogeneous background environments of cells and tissue. We present RASP, Radiality Analysis of Single Puncta, a bioimaging-segmentation method that solves this problem. RASP removes false-positive puncta that other analysis methods detect and detects features over a broad range of spatial scales: from single proteins to complex cell phenotypes. RASP outperforms the state-of-the-art methods in precision and speed using image gradients to separate Gaussian-shaped objects from the background. We demonstrate RASP's power by showing that it can extract spatial correlations between microglia, neurons, and α-synuclein oligomers in the human brain. This sensitive, computationally efficient approach enables fluorescent puncta and cellular features to be distinguished in cellular and tissue environments, with sensitivity down to the level of the single protein. Python and MATLAB codes, enabling users to perform this RASP analysis on their own data, are provided as Supporting Information and links to third-party repositories.


Asunto(s)
Encéfalo , Humanos
5.
Ann Intern Med ; 177(4): 507-513, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38437692

RESUMEN

Major depressive disorder (MDD) is a severe mood disorder that affects at least 8.4% of the adult population in the United States. Characteristics of MDD include persistent sadness, diminished interest in daily activities, and a state of hopelessness. The illness may progress quickly and have devastating consequences if left untreated. Eight performance measures are available to evaluate screening, diagnosis, and successful management of MDD. However, many performance measures do not meet the criteria for validity, reliability, evidence, and meaningfulness.The American College of Physicians (ACP) embraces performance measurement as a means to externally validate the quality of care of practices, medical groups, and health plans and to drive reimbursement processes. However, a plethora of performance measures that provide low or no value to patient care have inundated physicians, practices, and systems and burdened them with collecting and reporting of data. The ACP's Performance Measurement Committee (PMC) reviews performance measures using a validated process to inform regulatory and accreditation bodies in an effort to recognize high-quality performance measures, address gaps and areas for improvement in performance measures, and help reduce reporting burden. Out of 8 performance measures, the PMC found only 1 measure (suicide risk assessment) that was valid at all levels of attribution. This paper presents a review of MDD performance measures and highlights opportunities to improve performance measures addressing MDD management.


Asunto(s)
Trastorno Depresivo Mayor , Adulto , Humanos , Estados Unidos , Trastorno Depresivo Mayor/diagnóstico , Indicadores de Calidad de la Atención de Salud , Reproducibilidad de los Resultados
7.
Ann Intern Med ; 176(10): 1386-1391, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37782922

RESUMEN

Primary osteoporosis is characterized by decreasing bone mass and density and reduced bone strength that leads to a higher risk for fracture, especially hip and spine fractures. The prevalence of osteoporosis in the United States is estimated at 12.6% for adults older than 50 years. Although it is most frequently diagnosed in White and Asian females, it still affects males and females of all ethnicities. Osteoporosis is considered a major health issue, which has prompted the development and use of several performance measures to assess and improve the effectiveness of screening, diagnosis, and treatment. These performance measures are often used in accountability, public reporting, and/or payment programs. However, the reliability, validity, evidence, attribution, and meaningfulness of performance measures have been questioned. The purpose of this paper is to present a review of current performance measures on osteoporosis and inform physicians, payers, and policymakers in their selection of performance measures for this condition. The Performance Measurement Committee identified 6 osteoporosis performance measures relevant to internal medicine physicians, only 1 of which was found valid at all levels of attribution. This paper also proposes a performance measure concept to address a performance gap for the initial approach to therapy for patients with a new diagnosis of osteoporosis based on the current American College of Physicians guideline.


Asunto(s)
Fracturas Óseas , Osteoporosis , Masculino , Femenino , Humanos , Adulto , Estados Unidos/epidemiología , Indicadores de Calidad de la Atención de Salud , Reproducibilidad de los Resultados , Osteoporosis/diagnóstico , Osteoporosis/terapia , Densidad Ósea , Fracturas Óseas/epidemiología
8.
Ann Intern Med ; 176(10): 1396-1404, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37722112

RESUMEN

DESCRIPTION: Evidence for the use of outpatient treatments in adults with confirmed COVID-19 continues to evolve with new data. This is version 2 of the American College of Physicians (ACP) living, rapid practice points focusing on 22 outpatient treatments for COVID-19, specifically addressing the dominant SARS-CoV-2 Omicron variant. METHODS: The Population Health and Medical Science Committee (formerly the Scientific Medical Policy Committee) developed this version of the living, rapid practice points on the basis of a living, rapid review done by the ACP Center for Evidence Reviews at Cochrane Austria at the University for Continuing Education Krems (Danube University Krems). This topic will be maintained as living and rapid by continually monitoring and assessing the impact of new evidence. PRACTICE POINT 1: Consider molnupiravir to treat symptomatic patients with confirmed mild to moderate COVID-19 in the outpatient setting who are within 5 days of the onset of symptoms and at a high risk for progressing to severe disease. PRACTICE POINT 2: Consider nirmatrelvir-ritonavir combination therapy to treat symptomatic patients with confirmed mild to moderate COVID-19 in the outpatient setting who are within 5 days of the onset of symptoms and at a high risk for progressing to severe disease. PRACTICE POINT 3: Do not use ivermectin to treat patients with confirmed mild to moderate COVID-19 in the outpatient setting. PRACTICE POINT 4: Do not use sotrovimab to treat patients with confirmed mild to moderate COVID-19 in the outpatient setting.


Asunto(s)
COVID-19 , Médicos , Adulto , Humanos , Pacientes Ambulatorios , SARS-CoV-2 , Antivirales/uso terapéutico
9.
PLoS Pathog ; 19(6): e1011484, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37390113

RESUMEN

Many viruses form highly pleomorphic particles. In influenza, virion structure is of interest not only in the context of virus assembly, but also because pleomorphic variations may correlate with infectivity and pathogenicity. We have used fluorescence super-resolution microscopy combined with a rapid automated analysis pipeline, a method well-suited to the study of large numbers of pleomorphic structures, to image many thousands of individual influenza virions; gaining information on their size, morphology and the distribution of membrane-embedded and internal proteins. We observed broad phenotypic variability in filament size, and Fourier transform analysis of super-resolution images demonstrated no generalized common spatial frequency patterning of HA or NA on the virion surface, suggesting a model of virus particle assembly where the release of progeny filaments from cells occurs in a stochastic way. We also showed that viral RNP complexes are located preferentially within Archetti bodies when these were observed at filament ends, suggesting that these structures may play a role in virus transmission. Our approach therefore offers exciting new insights into influenza virus morphology and represents a powerful technique that is easily extendable to the study of pleomorphism in other pathogenic viruses.


Asunto(s)
Gripe Humana , Orthomyxoviridae , Humanos , Ensamble de Virus , Virión
10.
J Neurosci ; 43(29): 5414-5430, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37286351

RESUMEN

Multiple myeloma (MM) is a neoplasia of B plasma cells that often induces bone pain. However, the mechanisms underlying myeloma-induced bone pain (MIBP) are mostly unknown. Using a syngeneic MM mouse model, we show that periosteal nerve sprouting of calcitonin gene-related peptide (CGRP+) and growth associated protein 43 (GAP43+) fibers occurs concurrent to the onset of nociception and its blockade provides transient pain relief. MM patient samples also showed increased periosteal innervation. Mechanistically, we investigated MM induced gene expression changes in the dorsal root ganglia (DRG) innervating the MM-bearing bone of male mice and found alterations in pathways associated with cell cycle, immune response and neuronal signaling. The MM transcriptional signature was consistent with metastatic MM infiltration to the DRG, a never-before described feature of the disease that we further demonstrated histologically. In the DRG, MM cells caused loss of vascularization and neuronal injury, which may contribute to late-stage MIBP. Interestingly, the transcriptional signature of a MM patient was consistent with MM cell infiltration to the DRG. Overall, our results suggest that MM induces a plethora of peripheral nervous system alterations that may contribute to the failure of current analgesics and suggest neuroprotective drugs as appropriate strategies to treat early onset MIBP.SIGNIFICANCE STATEMENT Multiple myeloma (MM) is a painful bone marrow cancer that significantly impairs the quality of life of the patients. Analgesic therapies for myeloma-induced bone pain (MIBP) are limited and often ineffective, and the mechanisms of MIBP remain unknown. In this manuscript, we describe cancer-induced periosteal nerve sprouting in a mouse model of MIBP, where we also encounter metastasis to the dorsal root ganglia (DRG), a never-before described feature of the disease. Concomitant to myeloma infiltration, the lumbar DRGs presented blood vessel damage and transcriptional alterations, which may mediate MIBP. Explorative studies on human tissue support our preclinical findings. Understanding the mechanisms of MIBP is crucial to develop targeted analgesic with better efficacy and fewer side effects for this patient population.


Asunto(s)
Enfermedades Óseas , Mieloma Múltiple , Tejido Nervioso , Humanos , Ratones , Masculino , Animales , Mieloma Múltiple/complicaciones , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Calidad de Vida , Dolor/metabolismo , Tejido Nervioso/metabolismo , Tejido Nervioso/patología , Ganglios Espinales/metabolismo
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