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1.
Nephrol Dial Transplant ; 37(10): 1993-2003, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34617572

RESUMO

BACKGROUND: Serum globulin is a major component of total protein and can be elevated in inflammatory disease states. While inflammation is common in hemodialysis patients and associated with mortality and morbidity, the association between serum globulin and mortality has never been examined in hemodialysis patients. METHODS: In a retrospective cohort of 104 164 incident hemodialysis patients treated by a large dialysis organization from 2007 to 2011, we explored the association between baseline serum globulin, albumin: globulin (A:G) ratio and serum protein levels and all-cause, cardiovascular and infection-related mortality with adjustments for demographic variables and laboratory markers of malnutrition and inflammation using Cox proportional hazards models. RESULTS: Patients with a globulin concentration >3.8 g/dL had a higher all-cause and infection-related mortality risk {hazard ratio [HR] 1.11 [95% confidence interval (CI) 1.06-1.16] and HR 1.28 [95% CI 1.09-1.51], respectively} in the fully adjusted model when compared with the reference group of 3.0- <3.2 g/dL. In addition, patients with an A:G ratio <0.75 had a 45% higher all-cause mortality hazard [HR 1.45 (95% CI 1.38-1.52)] and patients with total serum protein <5.5 g/dL had a 34% higher risk of death [1.34 (95% CI 1.27-1.42)] when compared with the reference (A:G ratio 1.05- <1.15 and total serum protein 6.5- <7 g/dL). CONCLUSIONS: Among incident hemodialysis patients, a higher globulin level was associated with a higher mortality risk independent of other markers of malnutrition and inflammation, including albumin. A lower A:G ratio and serum protein was also associated with a higher mortality hazard. The mechanisms that contribute to elevated serum globulin should be further explored.


Assuntos
Falência Renal Crônica , Desnutrição , Albuminas , Biomarcadores , Humanos , Inflamação/etiologia , Desnutrição/etiologia , Modelos de Riscos Proporcionais , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Soroglobulinas
2.
Am J Nephrol ; 52(1): 59-68, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33601382

RESUMO

BACKGROUND: Patients with ESRD on maintenance hemodialysis (MHD) are particularly susceptible to dysregulation of energy metabolism, which may manifest as protein energy wasting and cachexia. In recent years, the endocannabinoid system has been shown to play an important role in energy metabolism with potential relevance in ESRD. N-acylethanolamines are a class of fatty acid amides which include the major endocannabinoid ligand, anandamide, and the endogenous peroxisome proliferator-activated receptor-α agonists, oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). METHODS: Serum concentrations of OEA and PEA were measured in MHD patients and their correlations with various clinical/laboratory indices were examined. Secondarily, we evaluated the association of circulating PEA and OEA levels with 12-month all-cause mortality. RESULTS: Both serum OEA and PEA levels positively correlated with high-density lipoprotein-cholesterol levels and negatively correlated with body fat and body anthropometric measures. Serum OEA levels correlated positively with serum interleukin-6 (IL-6) (rho = 0.19; p = 0.004). Serum PEA and IL-6 showed a similar but nonsignificant trend (rho = 0.12; p = 0.07). Restricted cubic spline analyses showed that increasing serum OEA and PEA both trended toward higher mortality risk, and these associations were statistically significant for PEA (PEA ≥4.7 pmol/mL; reference: PEA <4.7 pmol/mL) after adjustments in a Cox model (hazard ratio 2.99; 95% confidence interval 1.04, 8.64). CONCLUSIONS: In MHD patients, OEA and PEA are significantly correlated with variables related to lipid metabolism and body mass. Additionally, higher serum levels of PEA are associated with mortality risk. Future studies are needed to examine the potential mechanisms responsible for these findings and their clinical implications.


Assuntos
Amidas/sangue , Endocanabinoides/sangue , Etanolaminas/sangue , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Ácidos Oleicos/sangue , Ácidos Palmíticos/sangue , Diálise Renal , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Brain Behav Immun ; 66: 257-276, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28755859

RESUMO

BACKGROUND: Despite the increased recognition of cerebellar injury in survivors of preterm birth, the neurodevelopmental consequences of isolated cerebellar injury have been largely unexplored and our current understanding of the functional deficits requires further attention in order to translate knowledge to best practices. Preterm infants are exposed to multiple stressors during their postnatal development including perinatal cerebellar haemorrhage (CBH) and postnatal infection, two major risk factors for neurodevelopmental impairments. METHODS: We developed a translational mouse model of CBH and/or inflammation to measure the short- and long-term outcomes in cerebellar structure and function. RESULTS: Mice exposed to early combined insults of CBH and early inflammatory state (EIS) have a delay in grasping acquisition, neonatal motor deficits and deficient long-term memory. CBH combined with late inflammatory state (LIS) does not induce neonatal motor problems but leads to poor fine motor function and long-term memory deficits at adulthood. Early combined insults result in poor cerebellar growth from postnatal day 15 until adulthood shown by MRI, which are reflected in diminished volumes of cerebellar structures. There are also decreases in volumes of gray matter and hippocampus. Cerebellar microgliosis appears 24h after the combined insults and persists until postnatal day 15 in the cerebellar molecular layer and cerebellar nuclei in association with a disrupted patterning of myelin deposition, a delay of oligodendrocyte maturation and reduced white matter cerebellar volume. CONCLUSIONS: Together, these findings reveal poor outcomes in developing brains exposed to combined cerebellar perinatal insults in association with cerebellar hypoplasia, persistence of microgliosis and alterations of cerebellar white matter maturation and growth.


Assuntos
Comportamento Animal , Doenças Cerebelares/patologia , Doenças Cerebelares/fisiopatologia , Inflamação/complicações , Hemorragias Intracranianas/complicações , Animais , Ansiedade/complicações , Doenças Cerebelares/complicações , Modelos Animais de Doenças , Feminino , Masculino , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Microglia/metabolismo , Atividade Motora , Substância Branca/patologia
4.
Analyst ; 139(6): 1403-11, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24471157

RESUMO

The core requirements for point-of-care (POC) diagnostics necessitate low-cost, portability, easily integrated sample preparation, and quick measurement time. Frequency-shift based magnetic sensing is a measurement technique utilizing a complementary metal-oxide-semiconductor (CMOS) integrated-circuit (IC) chip for magnetic label detection. The sensing scheme leverages the low-cost manufacturing of IC chips while demonstrating the potential for multiplexing capabilities. In this article, we present modifications to this scheme for POC viability. We introduce a handheld reusable reader and a disposable open-well cartridge for the detection of nucleic acids and antigens. The diagnostic system utilizes a novel "magnetic freezing" technique to reduce measurement time, obviates baseline measurement before or during biological assay, and reduces sensor noise. We utilize these enhancements for the room temperature, amplification-free detection of a 31 base-pair DNA oligomer and the interferon-γ (IFN-γ) protein. We have demonstrated reliable measurements down to 100 pM for the DNA assay and 1 pM for the protein.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA/análise , Interferon gama/análise , Sistemas Automatizados de Assistência Junto ao Leito , Técnicas Biossensoriais/economia , Desenho de Equipamento , Imunoensaio/economia , Imunoensaio/instrumentação , Limite de Detecção , Fenômenos Magnéticos , Sistemas Automatizados de Assistência Junto ao Leito/economia , Semicondutores/economia
5.
Case Rep Ophthalmol ; 15(1): 411-417, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690400

RESUMO

Introduction: Photodynamic therapy (PDT) has shown substantial benefit in the treatment of choroidal hemangioma (CH) in recent years. This report describes the use of PDT with overlapping spots in a patient with Sturge-Weber syndrome (SWS) and large circumscribed CH. Case Presentation: A 9-year-old girl with SWS and a history of glaucoma in her left eye was referred to a retina clinic for possible macular changes. Examination revealed decreased vision in the left eye, pigmentary changes in the macula, and choroidal thickening in the posterior pole. After being lost to follow-up for 2 years, the patient returned with further vision deterioration with best-corrected visual acuity (BCVA) of 20/150 and new subretinal fluid (SRF). Imaging findings were consistent with a diagnosis of CH and SRF. PDT with verteporfin was initiated on the entire area with multiple overlapping spots, resulting in resolution of SRF and improvement in visual acuity and choroidal contour. At 18-month post-treatment, the patient's BCVA was 20/25 with no recurrence of SRF or increased choroidal thickening. Significant pigmentary changes and subretinal hyper-reflective material were observed in the OCT of the treated area. Conclusion: Multiple overlapping laser spots of PDT can result in longstanding regression of large circumscribed CH in a patient with SWS with excellent final visual acuity. However, significant subretinal changes may also result following this method of treatment.

6.
ACS Appl Bio Mater ; 3(7): 4139-4147, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35025416

RESUMO

Cell-based therapies are becoming increasingly prominent in numerous medical contexts, particularly in regenerative medicine and the treatment of cancer. However, since the efficacy of the therapy is largely dependent on the concentration of therapeutic cells at the treatment area, a major challenge associated with cell-based therapies is the ability to move and localize therapeutic cells within the body. In this article, a technique based on dynamically programmable magnetic fields is successfully demonstrated to noninvasively aggregate therapeutic cells at a desired location. Various types of therapeutically relevant cells (neural stem cells, monocytes/macrophages, and chimeric antigen receptor T cells) are loaded with iron oxide nanoparticles and then focused at a particular site using externally controlled electromagnets. These experimental results serve as a readily scalable prototype for designing an apparatus that patients can wear to focus therapeutic cells at the anatomical sites needed for treatment.

7.
SAGE Open Med Case Rep ; 8: 2050313X20952650, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913652

RESUMO

Scleroderma renal crisis is a serious complication that can develop in certain patients with systemic sclerosis. Some risks have been identified as potential triggers of scleroderma renal crisis, including the high-dose oral corticosteroids. Here, we present a patient who developed clinically severe systemic sclerosis and scleroderma renal crisis after exposure to oral corticosteroids and intravitreal vascular endothelial growth factor blockade with bevacizumab for cotton wool spots. The patient's scleroderma renal crisis was severe, progressive, and refractory to the standard of care therapy: oral captopril. Biopsy showed a diffuse thrombotic microangiopathy and findings consistent with scleroderma renal crisis. We hypothesize that depletion of systemic vascular endothelial growth factor with intravitreal anti-vascular endothelial growth factor injections likely contributed to the particularly severe presentation seen in this case. Though the finding of a monoclonal gammopathy of undetermined significance is another complicating factor, this case suggests that vascular endothelial growth factor inhibition may be a newly recognized trigger of scleroderma renal crisis.

8.
Front Med (Lausanne) ; 7: 579603, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117836

RESUMO

Vascular endothelial growth factor (VEGF) inhibition can cause worsening hypertension, proteinuria, chronic kidney injury, and glomerular disease. Thrombotic microangiopathy (TMA) and other nephrotic disorders have been reported with systemic VEGF blockade. These same agents are given intravitreally for age-related macular degeneration (AMD) and diabetic retinopathy (DR), albeit at lower doses than those given for systemic indications. Systemic absorption of anti-VEGF agents when given intravitreally has been shown consistently along with evidence of significant intravascular VEGF suppression. While worsening hypertension has only been seen in some large-scale studies, case reports show worsening proteinuria and diverse glomerular diseases. These include TMA-associated lesions like focal and segmental glomerulosclerosis with collapsing features (cFSGS). In this paper, we report three cases of TMA likely associated with the use of intravitreal anti-VEGF therapy. These patients developed the signature lesion of VEGF blockade in a 6 to 11 month time frame after starting intravitreal VEGF inhibitors. The literature is reviewed showing similar cases. Intravitreal VEGF blockade may cause these adverse events in a hitherto unidentified subgroup of patients. Well-controlled prospective observational trials are needed to determine the event rate and identify which subgroups of patients are at increased risk. A registry for patients who develop worsening hypertension, proteinuria exacerbation, and glomerular diseases from intravitreal VEGF blockade is proposed.

9.
Magn Reson Med ; 61(6): 1310-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19319904

RESUMO

T(1rho) and T(2) relaxation time constants have been proposed to probe biochemical changes in osteoarthritic cartilage. This study aimed to evaluate the spatial correlation and distribution of T(1rho) and T(2) values in osteoarthritic cartilage. Ten patients with osteoarthritis (OA) and 10 controls were studied at 3T. The spatial correlation of T(1rho) and T(2) values was investigated using Z-scores. The spatial variation of T(1rho) and T(2) values in patellar cartilage was studied in different cartilage layers. The distribution of these relaxation time constants was measured using texture analysis parameters based on gray-level co-occurrence matrices (GLCM). The mean Z-scores for T(1rho) and T(2) values were significantly higher in OA patients vs. controls (P < 0.05). Regional correlation coefficients of T(1rho) and T(2) Z-scores showed a large range in both controls and OA patients (0.2-0.7). OA patients had significantly greater GLCM contrast and entropy of T(1rho) values than controls (P < 0.05). In summary, T(1rho) and T(2) values are not only increased but are also more heterogeneous in osteoarthritic cartilage. T(1rho) and T(2) values show different spatial distributions and may provide complementary information regarding cartilage degeneration in OA.


Assuntos
Algoritmos , Cartilagem Articular/fisiopatologia , Interpretação de Imagem Assistida por Computador/métodos , Articulação do Joelho/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/fisiopatologia , Adulto , Idoso , Simulação por Computador , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Magn Reson Imaging ; 26(9): 1215-20, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18502073

RESUMO

OBJECTIVE: T2 mapping has been used widely in detecting cartilage degeneration in osteoarthritis. Several scanning sequences have been developed in the determination of T2 relaxation times of tissues. However, the derivation of these times may vary from sequence to sequence. This study seeks to evaluate the sequence-dependent differences in T2 quantitation of cartilage, muscle, fat and bone marrow in the knee joint at 3 T. METHODS: Three commercial phantoms and 10 healthy volunteers were studied using 3 T MR. T2 relaxation times of the phantoms, cartilage, muscle, subcutaneous fat and marrow were derived using spin echo (SE), multiecho SE (MESE), fast SE (FSE) with varying echo train length (ETL), spiral and spoiler gradient (SPGR) sequences. The differences between these times were then evaluated using Student's t test. In addition, the signal-to-noise ratio (SNR) efficiency and coefficient of variation of T2 from each sequence were calculated. RESULTS: The average T2 relaxation time was 36.38+/-5.76 ms in cartilage and 34.08+/-6.55 ms in muscle, ranging from 27 to 45 ms in both tissues. The times for subcutaneous fat and marrow were longer and more varying, ranging from 41 to 143 ms and from 42 to 160 ms, respectively. In FSE acquisition, relaxation time significantly increases as ETL increases (P<.05). In cartilage, the SE acquisition yields the lowest T2 values (27.52+/-3.10 ms), which is significantly lower than those obtained from other sequences (P<.002). T2 values obtained from spiral acquisition (38.27+/-6.45 ms) were higher than those obtained from MESE (34.35+/-5.62 ms) and SPGR acquisition (31.64+/-4.53 ms). These differences, however, were not significant (P>.05). CONCLUSION: T2 quantification can be a valuable tool for the diagnosis of degenerative disease. Several different sequences exist to quantify the relaxation times of tissues. Sequences range in scan time, SNR efficiency, reproducibility and two- or three-dimensional mapping. However, when choosing a sequence for quantitation, it is important to realize that several factors affect the measured T2 relaxation time.


Assuntos
Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Tecido Adiposo/anatomia & histologia , Adulto , Medula Óssea/anatomia & histologia , Cartilagem Articular/anatomia & histologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Imagens de Fantasmas
12.
Nanoscale ; 7(17): 7780-9, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25848983

RESUMO

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed "cell box" was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain.


Assuntos
Separação Imunomagnética/métodos , Nanopartículas de Magnetita/química , Fagócitos/citologia , Animais , Linhagem Celular , Camundongos , Microglia , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/farmacocinética , Fagócitos/metabolismo
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