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1.
Sci Adv ; 8(5): eabl8920, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35108055

RESUMO

Dexamethasone is widely used as an immunosuppressive therapy and recently as COVID-19 treatment. Here, we demonstrate that dexamethasone sensitizes to ferroptosis, a form of iron-catalyzed necrosis, previously suggested to contribute to diseases such as acute kidney injury, myocardial infarction, and stroke, all of which are triggered by glutathione (GSH) depletion. GSH levels were significantly decreased by dexamethasone. Mechanistically, we identified that dexamethasone up-regulated the GSH metabolism regulating protein dipeptidase-1 (DPEP1) in a glucocorticoid receptor (GR)-dependent manner. DPEP1 knockdown reversed the phenotype of dexamethasone-induced ferroptosis sensitization. Ferroptosis inhibitors, the DPEP1 inhibitor cilastatin, or genetic DPEP1 inactivation reversed the dexamethasone-induced increase in tubular necrosis in freshly isolated renal tubules. Our data indicate that dexamethasone sensitizes to ferroptosis by a GR-mediated increase in DPEP1 expression and GSH depletion. Together, we identified a previously unknown mechanism of glucocorticoid-mediated sensitization to ferroptosis bearing clinical and therapeutic implications.


Assuntos
Dexametasona/farmacologia , Dipeptidases/genética , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Receptores de Glucocorticoides/metabolismo , Carbolinas/efeitos adversos , Carbolinas/farmacologia , Linhagem Celular , Dipeptidases/metabolismo , Imunofluorescência , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Imunofenotipagem , Oxirredução/efeitos dos fármacos , Piperazinas/efeitos adversos , Piperazinas/farmacologia
2.
J Immunol ; 207(11): 2799-2812, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740957

RESUMO

Absent in melanoma-2 (AIM2) is an inflammasome-forming innate immune sensor for dsDNA but also exhibits inflammasome-independent functions such as restricting cellular proliferation. AIM2 is expressed in the kidney, but its localization and function are not fully characterized. In normal human glomeruli, AIM2 localized to podocytes. In patients with glomerulonephritis, AIM2 expression increased in CD44+-activated parietal epithelial cells within glomerular crescents. To explore AIM2 effects in glomerular disease, studies in Aim2 -/- mice were performed. Aim2-/- glomeruli showed reduced expression of Wilm tumor gene-1 (WT1), WT1-driven podocyte genes, and increased proliferation in outgrowth assays. In a nephrotoxic serum (NTS)-induced glomerulonephritis model, Aim2-/- (B6) mice exhibited more severe glomerular crescent formation, tubular injury, inflammation, and proteinuria compared with wild-type controls. Inflammasome activation markers were absent in both Aim2 -/- and wild-type kidneys, despite an increased inflammatory transcriptomic signature in Aim2 -/- mice. Aim2 -/- mice also demonstrated dysregulated cellular proliferation and an increase in CD44+ parietal epithelial cells during glomerulonephritis. The augmented inflammation and epithelial cell proliferation in Aim2 -/- (B6) mice was not due to genetic background, as Aim2 -/- (B6.129) mice demonstrated a similar phenotype during NTS glomerulonephritis. The AIM2-like receptor (ALR) locus was necessary for the inflammatory glomerulonephritis phenotype observed in Aim2 -/- mice, as NTS-treated ALR -/- mice displayed equal levels of injury as wild-type controls. Podocyte outgrowth from ALR -/- glomeruli was still increased, however, confirming that the ALR locus is dispensable for AIM2 effects on epithelial cell proliferation. These results identify a noncanonical role for AIM2 in suppressing inflammation and epithelial cell proliferation during glomerulonephritis.


Assuntos
Proteínas de Ligação a DNA/imunologia , Células Epiteliais/imunologia , Glomerulonefrite/imunologia , Inflamação/imunologia , Animais , Proliferação de Células , Proteínas de Ligação a DNA/deficiência , Feminino , Glomerulonefrite/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Curr Rheumatol Rev ; 17(3): 349-359, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33308132

RESUMO

OBJECTIVE: For patients with Rheumatoid Arthritis (RA) who do not achieve adequate clinical response with combined conventional synthetic disease-modifying anti-rheumatic drugs (cs- DMARDs), initiation of advanced therapies such as biologic DMARDs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs) is recommended. Tumour necrosis factor inhibitors (TNFi) are the oldest and most commonly used subgroup of advanced therapies. In the last decade, new non-TNFi advanced therapy options have become available. We described the relative use of TNFi vs. non-TNFi in Ontario-based practices from 2008-2017. METHODS: Adult patients with RA enrolled in the Ontario Best Practices Research Initiative (OBRI) database who started bDMARDs or tsDMARDs anytime during or within 30 days prior to enrollment were included. The proportion of patients treated with TNFi vs. non-TNFi agents between 2008 and 2017 was described for all patients and those initiating their first bDMARD/tsDMARD. All TNFi therapies were included. Non-TNFi included Abatacept, Rituximab, Tocilizumab, and Tofacitinib. RESULTS: A total of 1,057 patients were included, of whom 72.0% were bDMARD/tsDMARD naïve. In 2008, the relative non-TNFi use was 5.4% in all patients while it was 0% in bDMARD/ts- DMARD-naïve patients. In 2017, the proportion of patients using non-TNFi increased to 33.8% among all patients and 33.3% in bDMARD/tsDMARD-naïve patients. CONCLUSION: This descriptive analysis of data from the OBRI cohort reveals that TNFi are still used in the majority of cases; however, there has been an increase in the use of non-TNFi therapies both overall and as first-line advanced therapy. This trend towards non-TNFi therapies as first-line advanced therapy may be partially explained by the shift in guideline recommendations from TNFi as first-line to any of the advanced therapeutics.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Bases de Dados Factuais , Humanos , Ontário
4.
Cureus ; 12(5): e8130, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32550050

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition caused by overproduction of inflammatory cytokines and overactivation of macrophages that can progress to multiorgan dysfunction and failure. Although there are guidelines that attempt to recognize the condition in its early stage, diagnosis can be very challenging due to heterogeneous presentations of HLH. Symptoms and clinical findings include fever, neurologic complaints, respiratory issues, liver dysfunction, cytopenias, amongst others most of which are not specific to HLH. In addition, response to treatment can be highly variable, necessitating an individualized treatment plan based on the presentation. We present a case of a 21-year-old female with a history of biopsy-proven inflammatory myositis on azathioprine and prednisone who presented with fever, hypotension, and pancytopenia. Additional imaging studies showed multiorgan involvement, including pneumonia, pyelonephritis, and splenomegaly. A bone marrow biopsy of her iliac crest showed hemophagocytosis and the infectious workup confirmed cytomegalovirus (CMV) infection, which led to the diagnosis of CMV-induced HLH. She was treated initially with anakinra for macrophage activation syndrome (MAS) in addition to dexamethasone and ganciclovir. Unfortunately, she did not respond to anakinra and was subsequently switched to etoposide with dexamethasone and valganciclovir, which subsequently helped our patient to recover clinically. Our case highlights the challenging nature of HLH and the importance of early detection and a personalized treatment plan in achieving optimal outcomes in patients with HLH.

5.
Cell ; 178(5): 1205-1221.e17, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31442408

RESUMO

A hallmark feature of inflammation is the orchestrated recruitment of neutrophils from the bloodstream into inflamed tissue. Although selectins and integrins mediate recruitment in many tissues, they have a minimal role in the lungs and liver. Exploiting an unbiased in vivo functional screen, we identified a lung and liver homing peptide that functionally abrogates neutrophil recruitment to these organs. Using biochemical, genetic, and confocal intravital imaging approaches, we identified dipeptidase-1 (DPEP1) as the target and established its role as a physical adhesion receptor for neutrophil sequestration independent of its enzymatic activity. Importantly, genetic ablation or functional peptide blocking of DPEP1 significantly reduced neutrophil recruitment to the lungs and liver and provided improved survival in models of endotoxemia. Our data establish DPEP1 as a major adhesion receptor on the lung and liver endothelium and identify a therapeutic target for neutrophil-driven inflammatory diseases of the lungs.


Assuntos
Dipeptidases/metabolismo , Neutrófilos/fisiologia , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Animais , Cilastatina/farmacologia , Cilastatina/uso terapêutico , Dipeptidases/antagonistas & inibidores , Dipeptidases/genética , Modelos Animais de Doenças , Endotoxemia/mortalidade , Endotoxemia/patologia , Endotoxemia/prevenção & controle , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Infiltração de Neutrófilos/efeitos dos fármacos , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Taxa de Sobrevida
6.
Cell Rep ; 25(6): 1525-1536.e7, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30404007

RESUMO

The non-canonical caspase-4 and canonical NLRP3 inflammasomes are both activated by intracellular lipopolysaccharide (LPS), but the crosstalk between these two pathways remains unclear. Shiga toxin 2 (Stx2)/LPS complex, from pathogenic enterohemorrhagic Escherichia coli, activates caspase-4, gasdermin D (GSDMD), and the NLRP3 inflammasome in human THP-1 macrophages, but not mouse macrophages that lack the Stx receptor CD77. Stx2/LPS-mediated IL-1ß secretion and pyroptosis are dependent on mitochondrial reactive oxygen species (ROS) downstream of the non-canonical caspase-4 inflammasome and cleaved GSDMD, which is enriched at the mitochondria. Blockade of caspase-4 activation and ROS generation as well as GSDMD deficiency significantly reduces Stx2/LPS-induced IL-1ß production and pyroptosis. The NLRP3 inflammasome plays a significant role in amplifying Stx2/LPS-induced GSDMD cleavage and pyroptosis, with significant reduction of these responses in NLRP3-deficient THP-1 cells. Together, these data show that Stx2/LPS complex activates the non-canonical inflammasome and mitochondrial ROS upstream of the NLRP3 inflammasome to promote cytokine maturation and pyroptosis.


Assuntos
Caspases Iniciadoras/metabolismo , Inflamassomos/metabolismo , Lipopolissacarídeos/farmacologia , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Toxina Shiga/farmacologia , Animais , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Proteínas de Ligação a Fosfato , Piroptose/efeitos dos fármacos
7.
Mol Ther Oncolytics ; 10: 14-27, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30073187

RESUMO

Oncolytic virus (OV) therapy is an emerging cancer treatment that uses replicating viruses to infect and kill tumor cells and incite anticancer immunity. While the approach shows promise, it currently fails most patients, indicating strategies to improve OV activity are needed. Developing these will require greater understanding of OV biology, particularly in the context of OV delivery and clearance, the infection process within a complex tumor microenvironment, and the modulation of anticancer immunity. To help achieve this, we have established a technique for high-resolution 4D imaging of OV-host interactions within intact tissues of live mice using intravital microscopy (IVM). We show that oncolytic vesicular stomatitis virus (VSV) directly labeled with Alexa Fluor dyes is easily visualized by single- or multiphoton microscopy while retaining bioactivity in vivo. The addition of fluorophore-tagged antibodies and genetically encoded reporter proteins to image target cells and the virus infection enables real-time imaging of dynamic interactions between VSV and host cells in blood, tumor, and visceral organs of live mice. The method has sufficient in vivo resolution to observe leukocytes in blood binding to and transporting VSV particles, foci of VSV infection spreading through a tumor, and antigen-presenting cells in the spleen interacting with and being infected by VSV. Visualizing OV-host interactions by IVM represents a powerful new tool for studying OV therapy.

8.
Pilot Feasibility Stud ; 4: 127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30038794

RESUMO

BACKGROUND: Joint replacement provides significant improvements in pain, physical function, and quality of life in patients with osteoarthritis. With a growing body of evidence indicating that frailty can be treated, it is important to determine whether targeting frailty reduction in hip and knee replacement patients improves post-operative outcomes. OBJECTIVES: The primary objective is to examine the feasibility of a parallel group RCT comparing a preoperative multi-modal frailty intervention to usual care in pre-frail/frail older adults undergoing elective unilateral hip or knee replacements. The secondary objectives areTo explore potential efficacy of the multi-modal frailty intervention in improving frailty and mobility between baseline and 6 weeks post-surgery using Fried frailty phenotype and short performance physical battery (SPPB) respectively.To explore potential efficacy of the multi-modal frailty intervention on post-operative healthcare services use. METHODS/DESIGN: In a parallel group pilot RCT, participants will be recruited from the Regional Joint Assessment Program in Hamilton, Canada. Participants who are (1) ≥ 60 years old; (2) pre-frail (score of 1 or 2) or frail (score of 3-5; Fried frailty phenotype); (3) having elective unilateral hip or knee replacement; and (4) having surgery wait times between 3 and 10 months will be recruited and randomized to either the intervention or usual care group. The multi-modal frailty intervention components will include (1) tailored exercise program (center-based and/or home-based) with education and cognitive behavioral change strategies; (2) protein supplementation; (3) vitamin D supplementation; and (4) medication review. The main comparative analysis will take place at 6 weeks post-operative. The outcome assessors, data entry personnel, and data analysts are blinded to treatment allocation. Assessments: feasibility will be assessed by recruitment rate, retention rate, and data collection completion. Frailty and healthcare use and other clinical outcomes will be assessed. The study outcomes will be collected at the baseline, 1 week pre-operative, and 6 weeks and 6 months post-operative. DISCUSSION: This is the first study to examine the feasibility of multi-modal frailty intervention in pre-frail/frail older adults undergoing hip or knee replacement. This study will inform the planning and designing of multi-modal frailty interventional studies in hip and knee replacement patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT02885337.

9.
Inflammation ; 41(4): 1396-1408, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948504

RESUMO

Inflammation is an integral component of many diseases, including chronic kidney disease (CKD). ASC (apoptosis-associated speck-like protein containing CARD, also PYCARD) is the key inflammasome adaptor protein in the innate immune response. Since ASC specks, a macromolecular condensate of ASC protein, can be released by inflammasome-activated cells into the extracellular space to amplify inflammatory responses, the ASC protein could be an important biomarker in diagnostic applications. Herein, we describe the development and validation of a multiple reaction monitoring mass spectrometry (MRM-MS) assay for the accurate quantification of ASC in human biospecimens. Limits of detection and quantification for the signature DLLLQALR peptide (used as surrogate for the target ASC protein) were determined by the method of standard addition using synthetic isotope-labeled internal standard (SIS) peptide and urine matrix from a healthy donor (LOQ was 8.25 pM, with a ~ 1000-fold linear range). We further quantified ASC in the urine of CKD patients (8.4 ± 1.3 ng ASC/ml urine, n = 13). ASC was positively correlated with proteinuria and urinary IL-18 in CKD samples but not with urinary creatinine. Unfortunately, the ASC protein is susceptible to degradation, and patient urine that was thawed and refrozen lost 85% of the ASC signal. In summary, the MRM-MS assay provides a robust means to quantify ASC in biological samples, including clinical biospecimens; however, sample collection and storage conditions will have a critical impact on assay reliability.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/análise , Inflamassomos/metabolismo , Espectrometria de Massas/métodos , Proteínas Adaptadoras de Sinalização CARD/urina , Humanos , Interleucina-18/urina , Limite de Detecção , Peptídeos/análise , Proteinúria , Padrões de Referência , Insuficiência Renal Crônica/urina , Reprodutibilidade dos Testes
10.
BMC Pulm Med ; 18(1): 47, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29548305

RESUMO

BACKGROUND: Club cell protein-16 (CC16) expression has been associated with smoking-related lung function decline. The study hypothesis was that CC16 expression in both serum and bronchial epithelium is associated with lung function decline in smokers, and exposure to cigarette smoke will lead to reduction in CC16 expression in bronchial epithelial cells. METHODS: In a cohort of community-based male Chinese subjects recruited for lung function test in 2000, we reassessed their lung function ten years later and measured serum levels of CC16. CC16 expression was further assayed in bronchial epithelium from endobronchial biopsies taken from an independent cohort of subjects undergoing autofluorescence bronchoscopy, and tested for correlation between CC16 immunostaining intensity and lung function. In an in-vitro model, bronchial epithelial cells were exposed to cigarette smoke extract (CSE), and the expression levels of CC16 were measured in bronchial epithelial cells before and after exposure to CSE. RESULTS: There was a significant association between FEV1 decline and serum CC16 levels in smokers. Expression of CC16 in bronchial epithelium showed significant correlation with FEV1/FVC. Bronchial epithelial cells showed significant decrease in CC16 expression after exposure to CSE, followed by a subsequent rise in CC16 expression upon removal of CSE. CONCLUSIONS: Results of these clinical and laboratory investigations suggested that low serum CC16 was associated with smoking-related decline in lung function, demonstrated the first time in a Chinese cohort. The data also lend support to the putative role of CC16 in protection against smoking-related bronchial epithelial damage. (Abstract word count: 243) US CLINICAL TRIAL REGISTRY: NCT01185652 , first posted 20 August, 2010.


Assuntos
Fumar Cigarros/efeitos adversos , Células Epiteliais/metabolismo , Pulmão/fisiopatologia , Mucosa Respiratória/patologia , Uteroglobina/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Feminino , Volume Expiratório Forçado , Hong Kong , Humanos , Modelos Lineares , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Uteroglobina/genética
11.
J Am Soc Nephrol ; 29(4): 1165-1181, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29439156

RESUMO

Nonmicrobial inflammation contributes to CKD progression and fibrosis. Absent in melanoma 2 (AIM2) is an inflammasome-forming receptor for double-stranded DNA. AIM2 is expressed in the kidney and activated mainly by macrophages. We investigated the potential pathogenic role of the AIM2 inflammasome in kidney disease. In kidneys from patients with diabetic or nondiabetic CKD, immunofluorescence showed AIM2 expression in glomeruli, tubules, and infiltrating leukocytes. In a mouse model of unilateral ureteral obstruction (UUO), Aim2 deficiency attenuated the renal injury, fibrosis, and inflammation observed in wild-type (WT) littermates. In bone marrow chimera studies, UUO induced substantially more tubular injury and IL-1ß cleavage in Aim2-/- or WT mice that received WT bone marrow than in WT mice that received Aim2-/- bone marrow. Intravital microscopy of the kidney in LysM(gfp/gfp) mice 5-6 days after UUO demonstrated the significant recruitment of GFP+ proinflammatory macrophages that crawled along injured tubules, engulfed DNA from necrotic cells, and expressed active caspase-1. DNA uptake occurred in large vacuolar structures within recruited macrophages but not resident CX3CR1+ renal phagocytes. In vitro, macrophages that engulfed necrotic debris showed AIM2-dependent activation of caspase-1 and IL-1ß, as well as the formation of AIM2+ ASC specks. ASC specks are a hallmark of inflammasome activation. Cotreatment with DNaseI attenuated the increase in IL-1ß levels, confirming that DNA was the principal damage-associated molecular pattern in this process. Therefore, the activation of the AIM2 inflammasome by DNA from necrotic cells drives a proinflammatory phenotype that contributes to chronic injury in the kidney.


Assuntos
Proteínas de Ligação a DNA/fisiologia , DNA/metabolismo , Inflamassomos/fisiologia , Macrófagos/fisiologia , Insuficiência Renal Crônica/metabolismo , Animais , Transplante de Medula Óssea , Caspase 1/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Nefropatias Diabéticas/metabolismo , Ativação Enzimática , Fibrose , Humanos , Interleucina-1beta/metabolismo , Glomérulos Renais/metabolismo , Túbulos Renais/metabolismo , Leucócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necrose , Nefroesclerose/metabolismo , Fagocitose , Fenótipo , Quimera por Radiação , Células THP-1 , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
12.
J Rheumatol ; 45(2): 170-176, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29142041

RESUMO

OBJECTIVE: Previous studies combining biologic disease-modifying antirheumatic drugs (bDMARD) to treat rheumatoid arthritis (RA) have shown an increased risk of infection. However, the risk of infection with concurrent use of denosumab, a biologic agent for the treatment of osteoporosis, and a bDMARD remains unclear. Here, we evaluated the incidence of serious and opportunistic infections in patients treated concurrently with denosumab and a bDMARD and patients treated with a bDMARD alone. METHODS: A chart review of patients with RA from 2 Canadian rheumatology practices between July 1, 2010, and July 31, 2014, identified 2 groups of patients: those taking denosumab and a bDMARD concurrently (concurrent group) and those taking only a bDMARD (biologic-alone group). Patients were followed from the time of initiation of denosumab, or a matched index date for the biologic-alone group, to the end of the study or loss to followup. Instances of serious or opportunistic infections were recorded. RESULTS: A total of 308 patients (n = 102 for the concurrent group and n = 206 for the biologic-alone group) were evaluated. Within the concurrent group, 3 serious infection events occurred. Within the biologic-alone group, 4 serious infection events and 1 opportunistic infection event occurred. In both groups, all patients with serious or opportunistic infection recovered, and there were no instances of death during the study period. CONCLUSION: This study demonstrated a low occurrence of serious and opportunistic infections in patients with RA taking bDMARD, including patients with concurrent denosumab use.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Infecções Oportunistas/epidemiologia , Idoso , Antirreumáticos/efeitos adversos , Produtos Biológicos/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Canadá/epidemiologia , Estudos de Coortes , Denosumab/efeitos adversos , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/etiologia , Osteoporose/tratamento farmacológico , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
Transplantation ; 98(4): 402-10, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-24918613

RESUMO

BACKGROUND: Protease inhibitor 9 (PI-9) is an intracellular serpin that specifically inhibits granzyme B, a cytotoxic serine protease found in the cytosolic granules of cytotoxic T lymphocytes and natural killer cells. Enhanced cortical expression of PI-9 has been observed in kidney allografts with subclinical rejection, suggesting that the tubular epithelial cell (TEC) expression of this protein may have a protective role and attenuate overt allograft rejection. METHODS AND RESULTS: We demonstrate that TEC express SPI-6 protein, the murine homolog of PI-9, basally with a modest increase after cytokine exposure. Tubular epithelial cell expression of SPI-6 blocks granzyme B-mediated death because TEC from SPI-6 null kidneys have increased susceptibility to cytotoxic CD8+ cells in vitro. The role of SPI-6 was tested in a mouse kidney transplant model using SPI-6 null or wild type donor kidneys (H-2) into nephrectomized recipients (H-2). SPI-6 null kidney recipients demonstrated reduced renal function at day 8 after transplantation compared to controls (creatinine, 113±23 vs. 28±3 µmol/L; n=5; P<0.01), consistent with observed tubular injury and extensive mononuclear cell infiltration. Loss of donor kidney SPI-6 shortened graft survival time (20±19 vs. 66±33 days; n=8-10; P<0.001). CONCLUSION: Our data show for the first time that resistance of kidney TEC to cytotoxic T-cell granzyme B-induced death in vitro and in vivo is mediated by the expression of SPI-6. We suggest that SPI-6 is an important endogenous mechanism to prevent rejection injury from perforin or granzyme B effectors and enhanced PI-9 or SPI-6 expressions by TEC may provide protection from diverse forms of inflammatory kidney injury and promote long-term allograft survival.


Assuntos
Sobrevivência de Enxerto , Granzimas/antagonistas & inibidores , Transplante de Rim , Túbulos Renais/patologia , Proteínas de Membrana/fisiologia , Serpinas/fisiologia , Aloenxertos , Animais , Células Cultivadas , Células Epiteliais/patologia , Rejeição de Enxerto , Granzimas/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
15.
Asian J Endosc Surg ; 7(1): 63-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24450347

RESUMO

Single-incision laparoscopic hepatic resection has been attracting increased attention from the surgical community in recent years. While there have been reports and studies on this procedure, none has suggested the possibility of doing repeated hepatic resections via a single incision. This report on three such cases aims to determine the feasibility and safety of this approach for such patients. Three patients who had previously had liver resections underwent single-incision laparoscopic hepatic resection in our center. Patient demographics, type of port and instruments used, operating time, complications and incision length were collected. The operating time in each case was less than 230 min. The incision length for the single-port device was 3.5 cm or less. The length of hospital stay was less than 5 days in each case. Intra-operative blood loss was limited to 250 mL in each case. There were no immediate postoperative complications related to hepatic resection. Single-incision laparoscopic hepatic resection is feasible for selected patients who have had previous hepatic resections. Because the port entry site for the single-incision laparoscopic approach is usually slightly larger than that for the conventional approach, it is safer in re-resection cases where there may be adhesions from previous surgery. Other possible benefits, such as cosmesis and reduced port-associated morbidity, are mainly related to the use of only one small incision.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Neoplasias Hepáticas/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação
16.
Plant Biotechnol J ; 12(4): 425-35, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24373324

RESUMO

The incretin hormone glucagon-like peptide-1 (GLP-1) is recognized as a promising candidate for the treatment of type 2 diabetes (T2D), with one of its mimetics, exenatide (synthetic exendin-4) having already been licensed for clinical use. We seek to further improve the therapeutic efficacy of exendin-4 (Ex-4) using innovative fusion protein technology. Here, we report the production in plants a fusion protein containing Ex-4 coupled with human transferrin (Ex-4-Tf) and its characterization. We demonstrated that plant-made Ex-4-Tf retained the activity of both proteins. In particular, the fusion protein stimulated insulin release from pancreatic ß-cells, promoted ß-cell proliferation, stimulated differentiation of pancreatic precursor cells into insulin-producing cells, retained the ability to internalize into human intestinal cells and resisted stomach acid and proteolytic enzymes. Importantly, oral administration of partially purified Ex-4-Tf significantly improved glucose tolerance, whereas commercial Ex-4 administered by the same oral route failed to show any significant improvement in glucose tolerance in mice. Furthermore, intraperitoneal (IP) injection of Ex-4-Tf showed a beneficial effect in mice similar to IP-injected Ex-4. We also showed that plants provide a robust system for the expression of Ex-4-Tf, producing up to 37 µg prEx-4-Tf/g fresh leaf weight in transgenic tobacco and 137 µg prEx-4-Tf/g freshweight in transiently transformed leaves of N. benthamiana. These results indicate that Ex-4-Tf holds substantial promise as a new oral therapy for type 2 diabetes. The production of prEx-4-Tf in plants may offer a convenient and cost-effective method to deliver the antidiabetic medicine in partially processed plant food products.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Nicotiana/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/uso terapêutico , Administração Oral , Animais , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA Bacteriano/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Eletroforese em Gel de Poliacrilamida , Endocitose/efeitos dos fármacos , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Mucosa Gástrica/metabolismo , Vetores Genéticos/metabolismo , Glucose/farmacologia , Teste de Tolerância a Glucose , Homeostase/efeitos dos fármacos , Humanos , Injeções Intraperitoneais , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/farmacologia , Nicotiana/genética
17.
J Oncol ; 2012: 958596, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22619678

RESUMO

Introduction. ADT is used in the management of locally advanced and metastatic disease. The detrimental effect of ADT on bone density is well documented. This study assesses care gaps in screening, prevention and treatment of osteoporosis among prostate cancer patients. Methods. We conducted a retrospective cohort study for patients diagnosed with non-metastatic prostate cancer on ADT. Charts from a tertiary oncology center were assessed for utilization of DXA scan, prescription of calcium, vitamin D, calcitonin and bisphosphonates.Bivariate analysis was used to determine the effect of patient characteristics and likelihood for osteoporosis screening. Results. 149 charts were reviewed, with 3-year mean follow-up. 58.8% of men received a baseline DXA, of which 20.3% had a repeat DXA within their follow-up periods.In all, 28% were appropriately screened and managed for osteoporosis (received repeat DXA, bisphosphonate). In bivariate analysis, the number of ADT injections which correlate with the duration of androgen suppression was significantly associated with the number of DXA scans. Conclusions. Our study found a care gap in the screening, prevention, and treatment of osteoporosis in this population. Patients receiving the most ADT injections were more likely to be screened. Our results suggest healthcare providers treating prostate cancer are insufficiently screening and treating this susceptible population. We suggest baseline measurement of BMD at the initiation of ADT with periodic reassessment during therapy.

18.
Environ Sci Technol ; 44(14): 5483-9, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20550185

RESUMO

We investigated the condensed-phase reactions of biogenic VOCs with C double bond C bonds (limonene, C(10)H(16), and terpineol, C(10)H(18)O) catalyzed by sulfuric acid by both bulk solution (BS) experiments and gas-particle (GP) experiments using a flow cell reactor. Product analysis by gas chromatography-mass spectrometry (GC-MS) showed that cationic polymerization led to dimeric and trimeric product formation under conditions of relative humidity (RH) <20% (in the GP experiments) and a sulfuric acid concentration of 57.8 wt % (in the BS experiments), while hydration occurred under conditions of RH > 20% (in the GP experiments) and sulfuric acid concentrations of 46.3 wt % or lower (in the BS experiments). Apparent partitioning coefficients (K(p,rxn)) were estimated from the GP experiments by including the reaction products. Only under extremely low RH conditions (RH < 5%) did the values of K(p,rxn) ( approximately 5 x 10(-6) m(3)/microg for limonene and approximately 2 x 10(-5) m(3)/microg for terpineol) substantially exceed the physical partitioning coefficients (K(p) = 6.5 x 10(-8) m(3)/microg for limonene and =2.3 x 10(-6) m(3)/microg for terpineol) derived from the absorptive partitioning theory. At RH higher than 5%, the apparent partitioning coefficients (K(p,rxn)) of both limonene and terpineol were in the same order of magnitude as the K(p) values derived from the absorptive partitioning theory. Compared with other conditions including VOC concentration and degree of neutralization (by ammonium) of acidic particles, RH is a critical parameter that influences both the reaction mechanisms and the uptake ability (K(p,rxn) values) of these processes. The finding suggests that RH needs to be considered when taking the effects of acid-catalyzed reactions into account in estimating organic aerosol formation from C double bond C containing VOCs.


Assuntos
Ácidos/química , Cicloexenos/química , Gases/química , Material Particulado/química , Terpenos/química , Aerossóis , Catálise , Limoneno
19.
J Immunol ; 185(2): 967-73, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20548025

RESUMO

Renal ischemia reperfusion injury (IRI) occurs after reduced renal blood flow and is a major cause of acute injury in both native and transplanted kidneys. Studies have shown diverse cell types in both the innate and the adaptive immune systems participate in kidney IRI as dendritic cells, macrophages, neutrophils, B cells, CD4(+) NK(+) cells, and CD4(+) T cells all contribute to this form of injury. Recently, we have found that NK cells induce apoptosis in tubular epithelial cells (TECs) and also contribute to renal IRI. However, the mechanism of NK cell migration and activation during kidney IRI remains unknown. In this study, we have identified that kidney TECs express a high level of osteopontin (OPN) in vitro and in vivo. C57BL/6 OPN-deficient mice have reduced NK cell infiltration with less tissue damage compared with wild-type C57BL/6 mice after ischemia. OPN can directly activate NK cells to mediate TEC apoptotic death and can also regulate chemotaxis of NK cells to TECs. Taken together, our study's results indicate that OPN expression by TECs is an important factor in initial inflammatory responses that involves NK cells activity in kidney IRI. Inhibiting OPN expression at an early stage of IRI may be protective and preserve kidney function after transplantation.


Assuntos
Células Epiteliais/metabolismo , Rim/irrigação sanguínea , Células Matadoras Naturais/imunologia , Osteopontina/metabolismo , Traumatismo por Reperfusão/imunologia , Animais , Apoptose/imunologia , Movimento Celular/imunologia , Células Cultivadas , Feminino , Citometria de Fluxo , Expressão Gênica , Imuno-Histoquímica , Rim/metabolismo , Rim/patologia , Túbulos Renais/citologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Osteopontina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Respirology ; 13(3): 478-80, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18399878

RESUMO

A 53-year-old lady with blood-stained sputum and pleuritic pain had a lingular opacity on CXR which failed to resolve. A bronchial aspirate and transbronchial biopsy revealed features of bronchocentric granulomatosis with dichotomous branching hyphae suggestive of Aspergillus infection. However, subsequent fungal culture grew Pseudallescheria boydii. This case demonstrates the similarity of clinical and histological features caused by these two fungi. This appears to be the first reported case of pulmonary pseudallescheria with a bronchocentric granulomatous response.


Assuntos
Aspergilose Broncopulmonar Alérgica/diagnóstico , Aspergillus fumigatus/isolamento & purificação , Pulmão/microbiologia , Micetoma/diagnóstico , Pseudallescheria/isolamento & purificação , Aspergilose Broncopulmonar Alérgica/microbiologia , Aspergilose Broncopulmonar Alérgica/patologia , Aspergillus fumigatus/patogenicidade , Feminino , Humanos , Pulmão/patologia , Pessoa de Meia-Idade , Micetoma/microbiologia , Micetoma/patologia , Pseudallescheria/patogenicidade
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