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1.
Adv Sci (Weinh) ; 10(20): e2206787, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37114795

RESUMO

A nephrogenic progenitor cell (NP) with cancer stem cell characteristics driving Wilms tumor (WT) using spatial transcriptomics, bulk and single cell RNA sequencing, and complementary in vitro and transplantation experiments is identified and characterized. NP from WT samples with NP from the developing human kidney is compared. Cells expressing SIX2 and CITED1 fulfill cancer stem cell criteria by reliably recapitulating WT in transplantation studies. It is shown that self-renewal versus differentiation in SIX2+CITED1+ cells is regulated by the interplay between integrins ITGß1 and ITGß4. The spatial transcriptomic analysis defines gene expression maps of SIX2+CITED1+ cells in WT samples and identifies the interactive gene networks involved in WT development. These studies define SIX2+CITED1+ cells as the nephrogenic-like cancer stem cells of WT and points to the renal developmental transcriptome changes as a possible driver in regulating WT formation and progression.


Assuntos
Neoplasias Renais , Tumor de Wilms , Humanos , Fatores de Transcrição/genética , Tumor de Wilms/genética , Tumor de Wilms/metabolismo , Tumor de Wilms/patologia , Rim , Células-Tronco Neoplásicas/metabolismo , Neoplasias Renais/genética
4.
Anesth Analg ; 132(2): 293-304, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32769382

RESUMO

Aging is associated with loss of function across organ systems, contributing to systemic frailty. Loss of skeletal muscle mass and function, in particular, is a major source of frailty in older adults, severely impacting quality of life. Some loss of muscle mass and strength with aging is inevitable, and sarcopenia, the severe loss of muscle mass with aging, is common. Sarcopenia is determined in part by genetics but can be modified by lifestyle choices. The pathophysiologic underpinnings of sarcopenia are complex and multifactorial. In this review, the causes of sarcopenia are surveyed at the systems, cell, subcellular, and molecular levels with emphasis on the interplay between these various causes of this degenerative disease process.


Assuntos
Envelhecimento/patologia , Idoso Fragilizado , Fragilidade/patologia , Músculo Esquelético/patologia , Sarcopenia/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Fragilidade/genética , Fragilidade/metabolismo , Fragilidade/fisiopatologia , Interação Gene-Ambiente , Predisposição Genética para Doença , Indicadores Básicos de Saúde , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Prognóstico , Fatores de Risco , Sarcopenia/genética , Sarcopenia/metabolismo , Sarcopenia/fisiopatologia
5.
J Neuroimaging ; 30(5): 697-703, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32705733

RESUMO

BACKGROUND AND PURPOSE: In hepatic encephalopathy (HE), osmotic stressors promoting brain edema result in a compensatory drop in the astrocyte metabolite myo-inositol (mI). Identifying differences between nonalcoholic steatohepatitis (NASH) with and without HE and healthy controls using proton magnetic resonance spectroscopy (MRS) and evaluating hypoalbuminemia and hyperammonemia as osmotic stressors that predict the reduction of mI allow further understanding of mechanisms that promote brain edema in HE. The aim of this study was to assess brain edema in HE using characteristic MRS markers and serum albumin. METHODS: We evaluated between group differences among 19 NASH cirrhosis without HE (Crhs-HE) (age = 63 ± 8.7), 9 NASH cirrhosis with HE (Crhs+HE) (age = 63 ± 9.2), and 16 controls (age = 57.8 ± 11.7) using 1 H MRS. Glutamine (Gln/tCr) and serum albumin were evaluated as predictors of myo-inositol (mI/tCr) using linear regression. Statistical significance was set at P < .05 with adjustment for multiple comparisons. RESULTS: Brain mI/tCr was decreased, and Gln/tCr increased in Crhs+HE compared to Crhs-HE and controls in both brain regions (P < .001 for all). Evaluated together as joint predictors, serum albumin but not Gln/tCr significantly predicted mI/tCr in GM (P = .02 and P = .2, respectively) and PWM (P = .01 and P = .1, respectively). CONCLUSION: Low mI/tCr and increased Gln/tCr were characteristics of Crhs+HE. Low serum albumin was the strongest predictor of brain osmotic stress indicated by reduced mI/tCr, with no residual independent association seen for brain Gln/tCr concentration. This suggests that hypoalbuminemia in chronic liver disease may promote brain edema in HE.


Assuntos
Edema Encefálico/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encefalopatia Hepática/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Idoso , Biomarcadores/metabolismo , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Feminino , Glutamina/metabolismo , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/metabolismo , Humanos , Inositol/metabolismo , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo
6.
Nat Prod Rep ; 36(1): 35-107, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30003207

RESUMO

Covering: up to 2018With contributions from the global natural product (NP) research community, and continuing the Raw Data Initiative, this review collects a comprehensive demonstration of the immense scientific value of disseminating raw nuclear magnetic resonance (NMR) data, independently of, and in parallel with, classical publishing outlets. A comprehensive compilation of historic to present-day cases as well as contemporary and future applications show that addressing the urgent need for a repository of publicly accessible raw NMR data has the potential to transform natural products (NPs) and associated fields of chemical and biomedical research. The call for advancing open sharing mechanisms for raw data is intended to enhance the transparency of experimental protocols, augment the reproducibility of reported outcomes, including biological studies, become a regular component of responsible research, and thereby enrich the integrity of NP research and related fields.


Assuntos
Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Reprodutibilidade dos Testes
7.
Stem Cells Transl Med ; 8(3): 209-214, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30417988

RESUMO

We examined data and patterns in clinical islet transplant studies registered on ClinicalTrials.gov (CTgov) for treatment of type 1 diabetes (T1D), with a goal of extracting insights to apply in the design of a pluripotent stem cell-derived islet therapy. Clinical islet transplantation, as a cell therapy (rather than solid organ transplant) is a unique precedent for stem cell-based islet therapies. Registration activity shows that the field is not growing significantly, and newer registrations suggest that the reasons for stagnation include need for a more optimal site of infusion/transplantation, and especially a need for better immune protective strategies to advance a more effective and durable therapy for T1D. Stem Cells Translational Medicine 2019;8:209&214.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/fisiologia , Ilhotas Pancreáticas/citologia , Células-Tronco/citologia , Transplantes/citologia , Diferenciação Celular/fisiologia , Ensaios Clínicos como Assunto , Humanos
9.
Stem Cells Transl Med ; 8(1): 82-92, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30302937

RESUMO

Significant progress has been made to advance stem cell products as potential therapies for kidney diseases: various kinds of stem cells can restore renal function in preclinical models of acute and chronic kidney injury. Nonetheless this literature contains contradictory results, and for this reason, we focus this review on reasons for apparent discrepancies in the literature, because they contribute to difficulty in translating renal regenerative therapies. Differences in methodologies used to derive and culture stem cells, even those from the same source, in addition to the lack of standardized renal disease animal models (both acute and chronic), are important considerations underlying contradictory results in the literature. We propose that harmonized rigorous protocols for characterization, handling, and delivery of stem cells in vivo could significantly advance the field, and present details of some suggested approaches to foster translation in the field of renal regeneration. Our goal is to encourage coordination of methodologies (standardization) and long-lasting collaborations to improve protocols and models to lead to reproducible, interpretable, high-quality preclinical data. This approach will certainly increase our chance to 1 day offer stem cell therapeutic options for patients with all-too-common renal diseases. Stem Cells Translational Medicine 2019;8:82-92.


Assuntos
Nefropatias/terapia , Rim/citologia , Células-Tronco/citologia , Animais , Humanos , Transplante de Células-Tronco Mesenquimais , Regeneração/fisiologia
10.
Anesth Analg ; 126(1): 23-24, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29252480
12.
Nat Rev Cardiol ; 14(11): 679-693, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28748958

RESUMO

Early coronary artery reperfusion improves outcomes for patients with ST-segment elevation myocardial infarction (STEMI), but morbidity and mortality after STEMI remain unacceptably high. The primary deficits seen in these patients include inadequate pump function, owing to rapid infarction of muscle in the first few hours of treatment, and adverse remodelling of the heart in the months that follow. Given that attempts to further reduce myocardial infarct size beyond early reperfusion in clinical trials have so far been disappointing, effective therapies are still needed to protect the reperfused myocardium. In this Review, we discuss several approaches to preserving the reperfused heart, such as therapies that target the mechanisms involved in mitochondrial bioenergetics, pyroptosis, and autophagy, as well as treatments that harness the cardioprotective properties of inhaled anaesthetic agents. We also discuss potential therapies focused on correcting the no-reflow phenomenon and its effect on healing and adverse left ventricular remodelling.


Assuntos
Circulação Coronária/fisiologia , Reperfusão Miocárdica/métodos , Fenômeno de não Refluxo/prevenção & controle , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Remodelação Ventricular/fisiologia , Humanos , Fenômeno de não Refluxo/fisiopatologia , Período Pós-Operatório , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia
13.
Crit Care Med ; 45(7): 1115-1120, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28441235

RESUMO

OBJECTIVE: The study is based on previously reported mathematical analysis of arterial waveform that extracts hidden oscillations in the waveform that we called intrinsic frequencies. The goal of this clinical study was to compare the accuracy of left ventricular ejection fraction derived from intrinsic frequencies noninvasively versus left ventricular ejection fraction obtained with cardiac MRI, the most accurate method for left ventricular ejection fraction measurement. DESIGN: After informed consent, in one visit, subjects underwent cardiac MRI examination and noninvasive capture of a carotid waveform using an iPhone camera (The waveform is captured using a custom app that constructs the waveform from skin displacement images during the cardiac cycle.). The waveform was analyzed using intrinsic frequency algorithm. SETTING: Outpatient MRI facility. SUBJECTS: Adults able to undergo MRI were referred by local physicians or self-referred in response to local advertisement and included patients with heart failure with reduced ejection fraction diagnosed by a cardiologist. INTERVENTIONS: Standard cardiac MRI sequences were used, with periodic breath holding for image stabilization. To minimize motion artifact, the iPhone camera was held in a cradle over the carotid artery during iPhone measurements. MEASUREMENTS AND MAIN RESULTS: Regardless of neck morphology, carotid waveforms were captured in all subjects, within seconds to minutes. Seventy-two patients were studied, ranging in age from 20 to 92 years old. The main endpoint of analysis was left ventricular ejection fraction; overall, the correlation between ejection fraction-iPhone and ejection fraction-MRI was 0.74 (r = 0.74; p < 0.0001; ejection fraction-MRI = 0.93 × [ejection fraction-iPhone] + 1.9). CONCLUSIONS: Analysis of carotid waveforms using intrinsic frequency methods can be used to document left ventricular ejection fraction with accuracy comparable with that of MRI. The measurements require no training to perform or interpret, no calibration, and can be repeated at the bedside to generate almost continuous analysis of left ventricular ejection fraction without arterial cannulation.


Assuntos
Imageamento por Ressonância Magnética , Aplicativos Móveis , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Smartphone
15.
J Crit Care ; 35: 90-5, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27481741

RESUMO

Viewing the intensive care unit (ICU) as a control system with inputs (patients) and outputs (outcomes), we focus on actuation (therapies) of the system and how to enhance our understanding of status of patients and their trajectory in the ICU. To incorporate the results of these analytics meaningfully, we feel that a reassessment of predictive scoring systems and of ways to optimally characterize and display the patient's "state space" to clinicians is important. Advances in sensing (diagnostics) and computation have not yet led to significantly better actuation, and so we focus on ways that data can be used to improve actuation in the ICU, in particular by following therapeutic burden along with disease severity. This article is meant to encourage discussion about how the critical care community can best deal with the data they see each day, and prepare for recommendations that will inevitably arise from application of major federal and state initiatives in big data analytics and precision medicine.


Assuntos
Cuidados Críticos/normas , Procedimentos Clínicos , Avaliação de Resultados em Cuidados de Saúde , APACHE , Interpretação Estatística de Dados , Humanos , Unidades de Terapia Intensiva/normas , Risco , Estados Unidos
16.
Front Immunol ; 7: 140, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148260

RESUMO

Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood-brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients.

19.
J Crit Care ; 30(3): 652.e1-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25680579

RESUMO

The human body is a tightly controlled engineering miracle. However, medical training generally does not cover "control" (in the engineering sense) in physiology, pathophysiology, and therapeutics. A better understanding of how evolved controls maintain normal homeostasis is critical for understanding the failure mode of controlled systems, that is, disease. We believe that teaching and research must incorporate an understanding of the control systems in physiology and take advantage of the quantitative tools used by engineering to understand complex systems. Control systems are ubiquitous in physiology, although often unrecognized. Here we provide selected examples of the role of control in physiology (heart rate variability, immunity), pathophysiology (inflammation in sepsis), and therapeutic devices (diabetes and the artificial pancreas). We also present a high-level background to the concept of robustly controlled systems and examples of clinical insights using the controls framework.


Assuntos
Diabetes Mellitus/fisiopatologia , Retroalimentação Fisiológica/fisiologia , Frequência Cardíaca/fisiologia , Imunidade/fisiologia , Inflamação/fisiopatologia , Sepse/fisiopatologia , Diabetes Mellitus/terapia , Humanos , Pâncreas Artificial
20.
Interface Focus ; 4(5): 20140042, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25285200

RESUMO

Blood glucose levels are controlled by well-known physiological feedback loops: high glucose levels promote insulin release from the pancreas, which in turn stimulates cellular glucose uptake. Low blood glucose levels promote pancreatic glucagon release, stimulating glycogen breakdown to glucose in the liver. In healthy people, this control system is remarkably good at maintaining blood glucose in a tight range despite many perturbations to the system imposed by diet and fasting, exercise, medications and other stressors. Type 1 diabetes mellitus (T1DM) results from loss of the insulin-producing cells of the pancreas, the beta cells. These cells serve as both sensor (of glucose levels) and actuator (insulin/glucagon release) in a control physiological feedback loop. Although the idea of rebuilding this feedback loop seems intuitively easy, considerable control mathematics involving multiple types of control schema were necessary to develop an artificial pancreas that still does not function as well as evolved control mechanisms. Here, we highlight some tools from control engineering used to mimic normal glucose control in an artificial pancreas, and the constraints, trade-offs and clinical consequences inherent in various types of control schemes. T1DM can be viewed as a loss of normal physiologic controls, as can many other disease states. For this reason, we introduce basic concepts of control engineering applicable to understanding pathophysiology of disease and development of physiologically based control strategies for treatment.

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