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1.
Transplant Direct ; 8(12): e1414, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36406898

RESUMO

Delayed graft function (DGF) after kidney transplantation is associated with higher rates of acute rejection and poor graft survival and outcomes. Current DGF definitions based on posttransplant need for dialysis are not standardized and there are no objective methodologies for quantifying DGF severity. Methods: Using Organ Procurement and Transplantation Network data, we examined DGF, and used recipient serum creatinine at discharge as a correlate of renal function and DGF severity (mild: <2.5 mg/dL; severe: ≥2.5 mg/dL). The associations between donor and recipient factors and DGF severity were quantified using logistic regression. We also examined the associations between DGF severity and long-term recipient outcomes, adjusting for potential confounders. Results: A predictive model using donor and recipient factors had a reasonably good ability to discriminate mild (low creatinine) versus severe (high creatinine) DGF (c-statistic of 0.70). In Cox regression, DGF and creatinine at discharge were both independently associated with long-term outcomes, yet their effects differed depending on the outcome (graft function, death-censored graft function, recipient mortality). Our findings suggest that having DGF, but with relatively good renal function (creatinine <2.5) at discharge, may be less deleterious on graft and recipient survival compared with severe, prolonged DGF, which was associated with a decreased median graft survival of ~2.6 y compared with no DGF with low creatinine at discharge. Conclusions: Our novel DGF severity stratification identified unique factors associated with DGF severity, along with DGF's association with long-term graft and patient survival. The adverse cost and outcome implications of severe DGF warrant additional investigation to improve kidney transplantation practice.

2.
Transplant Direct ; 7(9): e738, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34386576

RESUMO

BACKGROUND: Focal segmental glomerulosclerosis (FSGS) is a common recurrent glomerulopathy associated with graft loss and patient survival after kidney transplantation (KT). However, its natural history, clinical predictors, and treatment response are still poorly understood. Steroid withdrawal regimens in KT have been associated with improvements in cardiovascular risk and patient outcomes. The Scripps Center for Organ Transplantation (SCOT) uses a rapid low-dose steroid withdrawal immunosuppression (IS) protocol for KT maintenance. METHODS: We assessed the impact of our protocol on FSGS disease recurrence over a 10-y period to reassess our steroid and IS protocols and to evaluate if our patient outcomes diverge from published data. We compared 4 groups: steroids always, steroid free, steroid switch on, and steroid weaned off. We used IS and induction-matched retrospective data from United Network for Organ Sharing (UNOS) to investigate patient and graft survival for FSGS at SCOT. RESULTS: Our analysis results differ from earlier studies showing that FSGS was associated with a higher risk of graft loss, perhaps because of selection of a UNOS data set filtered to match the SCOT IS protocol for making direct comparisons. Overall outcomes of graft failure and recipient death did not differ between SCOT patients and steroid-free transplant patient data from the UNOS data for FSGS. SCOT recurrence rate for FSGS was 7.5%, which was lower than in most published single-center studies. CONCLUSIONS: Based on our results, we believe that it is safe to continue the steroid avoidance protocols at SCOT and the steroid-free protocol may not be detrimental when the adverse effects and toxicities associated with steroid use are considered.

3.
J Radiol Prot ; 41(3)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34107455

RESUMO

Yttrium-90 (Y-90) radioembolization for the treatment of hepatocellular carcinoma can present safety challenges when transplanting recently treated Y-90 patients. To reduce surgeons' contact with radioactive tissue and remain within occupational dose limits, current guidelines recommend delaying transplants at least 14 days, if possible. We wanted to determine the level of radiation exposure to the transplant surgeon when explanting an irradiated liver before the recommended decay period. Anex-vivoradiation exposure analysis was conducted on the explanted liver of a patient who received Y-90 therapy 46 h prior to orthotopic liver transplant. To estimate exposure to the surgeon's hands, radiation dosimeter rings were placed inside three different surgical glove configurations and exposed to the explanted liver. Estimated radiation doses corrected for Y-90 decay were calculated. Radiation safety gloves performed best, with an average radiation exposure rate of 5.36 mSV h-1in the static hand position, an 83% reduction in exposure over controls with no glove (31.31 mSv h-1). Interestingly, non-radiation safety gloves also demonstrated reduced exposure rates, well below occupational regulation limits. Handling of Y-90 radiated organs within the immediate post-treatment period can be done safely and does not exceed federal occupational dose limits if appropriate gloves and necessary precautions are exercised.


Assuntos
Exposição Ocupacional , Exposição à Radiação , Hepatectomia , Humanos , Exposição Ocupacional/análise , Doses de Radiação , Radioisótopos de Ítrio/uso terapêutico
4.
PLoS One ; 16(3): e0247797, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661960

RESUMO

Since the initial identification of the novel coronavirus SARS-CoV-2 in December of 2019, researchers have raced to understand its pathogenesis and begun devising vaccine and treatment strategies. An accurate understanding of the body's temporal immune response against SARS-CoV-2 is paramount to successful vaccine development and disease progression monitoring. To provide insight into the antibody response against SARS-CoV-2, plasma samples from 181 PCR-confirmed COVID-19 patients collected at various timepoints post-symptom onset (PSO) were tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies via lateral flow. Additionally, 21 donors were tracked over time to elucidate patient-specific immune responses. We found sustained levels of anti-SARS-CoV-2 antibodies past 130 days PSO, with 99% positivity observed at 31-60 days PSO. By 61-90 days PSO, the percentage of IgM-/IgG+ results were nearly equal to that of IgM+/IgG+ results, demonstrating a shift in the immune response with a decrease in IgM antibody levels. Results from this study not only provide evidence that the antibody response to COVID-19 can persist for over 4 months, but also demonstrates the ability of Easy Check™ to monitor seroconversion and antibody response of patients. Easy Check was sufficiently sensitive to detect antibodies in patient samples as early as 1-4 days PSO with 86% positivity observed at 5-7 days PSO. Further studies are required to determine the longevity and efficacy of anti-SARS-CoV-2 antibodies, and whether they are protective against re-infection.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Teste Sorológico para COVID-19/instrumentação , Teste Sorológico para COVID-19/métodos , Desenho de Equipamento , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Adulto Jovem
5.
Transplant Proc ; 53(2): 569-580, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33549345

RESUMO

BACKGROUND: Transplant candidates can be listed at multiple transplant centers to increase the probability of receiving an organ. We evaluated the association between multilisting (ML) status and access to a deceased donor kidney transplant (DDKT) to determine if ML provides a long-term advantage regarding wait-list mortality and recipient outcomes. MATERIALS AND METHODS: Candidates between January 2010 and October 2017 were identified as either singly or multiply listed using Organ Procurement and Transplantation Network data and cohorts before and after implementation of the Kidney Allocation System (KAS). Cross-sectional logistic regression was used to assess relationships between candidate factors and ML prevalence (5.4%). RESULTS: Factors associated with ML pre-KAS included having blood type B (reference, type O; odds ratio [OR], 1.20; P < .001), having private insurance (OR, 1.5; P < .001), wait time (OR, 1.28; P < .001), and increasing calculated panel-reactive antibody (cPRA) (reference, cPRA 0-100; OR for cPRA 80-98, 2.83; OR for cPRA 99, 3.47; OR for cPRA 100, 5.18; P < .001). Transplant rates were double for multilisted vs singly listed recipients (adjusted hazard ratio [aHR], 2.16; P < .001). Extra-donor service area ML candidates received transplants 2.5 years quicker than single-listing (SL) candidates, conferring a 42% wait-list advantage. Recipient death (aHR, 0.94; P = .122) and graft failure (aHR, 0.91; P = .006) rates were also lower for ML recipients. CONCLUSIONS: In the KAS era, ML continues to increase the likelihood of receiving a DDKT and lower the incidence of wait-list mortality, and it confers a survival advantages over SL.


Assuntos
Transplante de Rim/estatística & dados numéricos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Listas de Espera/mortalidade , Adulto , Estudos Transversais , Feminino , Implementação de Plano de Saúde , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances
6.
Am J Infect Control ; 49(4): 506-507, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33388312

RESUMO

Coronavirus Disease 2019 infections among healthcare workers were widely reported in China and Europe as the pandemic expanded to the United States. In order to examine the infection rate among these essential workers, we combined results of SARS-CoV-2 serology testing offered free to healthcare workers at two large San Diego health systems when the antibody assays first became available.


Assuntos
COVID-19/epidemiologia , Atenção à Saúde , Pessoal de Saúde , Exposição Ocupacional , SARS-CoV-2 , Soroconversão , California/epidemiologia , Humanos
7.
Transplant Proc ; 53(3): 950-961, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33293041

RESUMO

Although interest in the role of donor-specific antibodies (DSAs) in kidney transplant rejection, graft survival, and histopathological outcomes is increasing, their impact on steroid avoidance or minimization in renal transplant populations is poorly understood. Primary outcomes of graft survival, rejection, and histopathological findings were assessed in 188 patients who received transplants between 2012 and 2015 at the Scripps Center for Organ Transplantation, which follows a steroid avoidance protocol. Analyses were performed using data from the United Network for Organ Sharing. Cohorts included kidney transplant recipients with de novo DSAs (dnDSAs; n = 27), preformed DSAs (pfDSAs; n = 15), and no DSAs (nDSAs; n = 146). Median time to dnDSA development (classes I and II) was shorter (102 days) than in previous studies. Rejection of any type was associated with DSAs to class I HLA (P < .05) and class II HLA (P < .01) but not with graft loss. Although mean fluorescence intensity (MFI) independently showed no association with rejection, an MFI >5000 showed a trend toward more antibody-mediated rejection (P < .06), though graft loss was not independently associated. Banff chronic allograft nephropathy scores and a modified chronic injury score were increased in the dnDSA cohort at 6 months, but not at 2 years (P < .001 and P < .08, respectively). Our data suggest that dnDSAs and pfDSAs impact short-term rejection rates but do not negatively impact graft survival or histopathological outcomes at 2 years. Periodic protocol post-transplant DSA monitoring may preemptively identify patients who develop dnDSAs who are at a higher risk for rejection.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Terapia de Imunossupressão/métodos , Isoanticorpos/imunologia , Transplante de Rim , Adulto , Estudos de Coortes , Feminino , Antígenos HLA/imunologia , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Esteroides , Transplantados
8.
Biopreserv Biobank ; 18(5): 425-440, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32833508

RESUMO

The human microbiome encompasses a variety of microorganisms that change dynamically and are in close contact with the body. The microbiome influences health and homeostasis, as well as the immune system, and any significant change in this equilibrium (dysbiosis) triggers both acute and chronic health conditions. Microbiome research has surged, in part, due to advanced sequencing technologies enabling rapid, accurate, and cost-effective identification of the microbiome. A major prerequisite for stool sample collection to study the gut microbiome in longitudinal prospective studies requires standardized protocols that can be easily replicated. However, there are still significant bottlenecks to stool specimen collection that contribute to low patient retention rates in microbiome studies. These barriers are further exacerbated in solid organ transplant recipients where diarrhea is estimated to occur in up to half the patient population. We sought to test two relatively easy sample collection methods (fecal swab and wipes) and compare them to the more cumbersome "gold" standard collection method (scoop) using two different sequencing technologies (16S ribosomal RNA sequencing and shotgun metagenomics). Our comparison of the collection methods shows that both the swabs and the wipes are comparable to the scoop method in terms of bacterial abundance and diversity. The swabs, however, were closer in representation to the scoop and were easier to collect and process compared to the wipes. Potential contamination of the swab and the wipe samples by abundant skin commensals was low in our analysis. Comparison of the two sequencing technologies showed that they were complementary, and that 16S sequencing provided enough coverage to detect and differentiate between bacterial species identified in the collected samples. Our pilot study demonstrates that alternative collection methods for stool sampling are a viable option in clinical applications, such as organ transplant studies. The use of these methods may result in better patient retention recruitment rates in serial microbiome studies.


Assuntos
Metagenômica , Transplante de Órgãos , Estudos de Viabilidade , Fezes , Voluntários Saudáveis , Humanos , Projetos Piloto , Estudos Prospectivos , RNA Ribossômico 16S
9.
J Alzheimers Dis ; 75(3): 959-969, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32390626

RESUMO

BACKGROUND: Aberrant angiogenesis may play a role in the development of Alzheimer's disease and related dementia. OBJECTIVE: To explore the relationship between angiogenesis activity and evidence of neurodegeneration among older adults. METHODS: Cross-sectional study of 49 older adults clinically characterized as cognitively normal, mild cognitive impairment, or early Alzheimer's disease. In addition to neuroimaging, we completed assays on peripheral blood, including: vascular endothelial growth factor, tumor necrosis factor, fibroblast growth factor, and amyloid-ß peptide 40. We used advanced polychromatic flow cytometry to phenotype circulating mononuclear cells to assess angiogenesis activity. RESULTS: Although we documented differences in cognitive performance, structural changes on neuroimaging, and burden of amyloid and tau on positron emission tomography, angiogenesis activity did not vary by group. Interestingly, VEGF levels were shown to be increased among subjects with mild cognitive impairment. In ANCOVA models controlling for age, sex, intracranial volume, and monocyte subpopulations, angiogenesis activity was correlated with increased white matter hyperintensities. CONCLUSION: We demonstrate a significant association between angiogenesis activity and cerebrovascular disease. To better understand the potential of angiogenesis as an intervention target, longitudinal studies are needed.


Assuntos
Encéfalo/patologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/patologia , Demência/diagnóstico , Demência/patologia , Neovascularização Patológica/diagnóstico , Idoso , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/sangue , Disfunção Cognitiva/complicações , Estudos Transversais , Demência/sangue , Demência/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neovascularização Patológica/sangue , Neovascularização Patológica/complicações , Tomografia por Emissão de Pósitrons
10.
PLoS One ; 13(9): e0203517, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30192852

RESUMO

The objective of this study was to investigate a possible mechanism of action of metronomic chlorambucil on glioma by studying the in vitro cytotoxicity and anti-angiogenic effects on glioma and endothelial cells, respectively. The in vitro LD50 and IC50 of chlorambucil were determined using human SF767 and U87-MG glioma cell lines, human microvascular endothelial cells (HMVECs) and human endothelial colony forming cells (ECFCs). Results were analyzed in the context of chlorambucil concentrations measured in the plasma of tumor-bearing dogs receiving 4 mg m-2 metronomic chlorambucil. The LD50 and IC50 of chlorambucil were 270 µM and 114 µM for SF767, and 390 µM and 96 µM for U87-MG, respectively. The IC50 of chlorambucil was 0.53 µM and 145 µM for the HMVECs and ECFCs, respectively. In pharmacokinetic studies, the mean plasma Cmax of chlorambucil was 0.06 µM. Results suggest that metronomic chlorambucil in dogs does not achieve plasma concentrations high enough to cause direct cytotoxic or growth inhibitory effects on either glioma or endothelial cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Clorambucila/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Glioma/metabolismo , Animais , Antineoplásicos Alquilantes/sangue , Antineoplásicos Alquilantes/farmacocinética , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Clorambucila/sangue , Clorambucila/farmacocinética , Cães , Relação Dose-Resposta a Droga , Células Endoteliais/citologia , Células Progenitoras Endoteliais/citologia , Glioma/sangue , Glioma/irrigação sanguínea , Humanos , Taxa de Depuração Metabólica
12.
Liver Transpl ; 23(11): 1372-1383, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28834180

RESUMO

Transplantation of liver grafts from donation after cardiac death (DCD) is limited. To identify barriers of DCD liver utilization, all active US liver transplant centers (n = 138) were surveyed, and the responses were compared with the United Network for Organ Sharing (UNOS) data. In total, 74 (54%) centers responded, and diversity in attitudes was observed, with many not using organ and/or recipient prognostic variables defined in prior studies and UNOS data analysis. Most centers (74%) believed lack of a system allowing a timely retransplant is a barrier to utilization. UNOS data demonstrated worse 1- and 5-year patient survival (PS) and graft survival (GS) in DCD (PS, 86% and 64%; GS, 82% and 59%, respectively) versus donation after brain death (DBD) recipients (PS, 90% and 71%; GS, 88% and 69%, respectively). Donor alanine aminotransferase (ALT), recipient Model for End-Stage Liver Disease (MELD), and cold ischemia time (CIT) significantly impacted DCD outcomes to a greater extent than DBD outcomes. At 3 years, relisting and retransplant rates were 7.9% and 4.6% higher in DCD recipients. To optimize outcome, our data support the use of DCD liver grafts with CIT <6-8 hours in patients with MELD ≤ 20. In conclusion, standardization of donor and recipient criteria, defining the impact of ischemic cholangiopathy, addressing donor hospital policies, and developing a strategy for timely retransplant may help to expand the use of these organs. Liver Transplantation 23 1372-1383 2017 AASLD.


Assuntos
Doença Hepática Terminal/cirurgia , Sobrevivência de Enxerto , Transplante de Fígado/métodos , Padrões de Prática Médica/normas , Obtenção de Tecidos e Órgãos/normas , Adulto , Aloenxertos/patologia , Aloenxertos/transplante , Atitude , Isquemia Fria/efeitos adversos , Doença Hepática Terminal/mortalidade , Rejeição de Enxerto/epidemiologia , Humanos , Fígado/patologia , Transplante de Fígado/efeitos adversos , Transplante de Fígado/psicologia , Transplante de Fígado/estatística & dados numéricos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/organização & administração , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Índice de Gravidade de Doença , Inquéritos e Questionários , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/organização & administração , Transplantes , Resultado do Tratamento , Estados Unidos
13.
Nutr Res ; 40: 75-84, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28473063

RESUMO

Monocytes are involved in immune responses, and specific monocyte subpopulations (MS) that express intermediate to high levels of CD16 are associated with obesity and cardiovascular events. Consuming high protein (HP) when dieting improves body composition and cardiometabolic health outcomes, but whether HP affects MS during weight loss remains unknown. We assessed the effect of HP on energy restriction (ER)-induced changes in MS in overweight and obese adults. The relations between MS and plasma lipids and lipoproteins were also examined. We hypothesized that, independent of protein intake, ER-induced weight loss would decrease the numbers of MS and that MS and plasma lipids and lipoproteins would be related. Thirty-two adults (age 52 ± 1 years, body mass index 31.3 ± 0.5 kg/m2, means ± S.E.) consumed either a normal protein (n=18) or HP (n=14) (0.8 vs 1.5 g•kg-1•d-1 protein) ER diet (750-kcal/d [3138-kJ/d] deficit) for 16 weeks. The HP diet included 0.7 g•kg-1•d-1 of milk protein isolate. Fasting plasma lipids, lipoproteins, and the numbers of MS were analyzed. Over time, independent of protein intake, CD14++CD16+ cell number decreased, whereas CD14dimCD16++, CD14+CD16+, and CD14+CD16- cell numbers remained unchanged. CD14dimCD16++ cell number was negatively associated with total cholesterol (TC) and triglyceride, while CD14++CD16+ cell number was positively associated with TC, low-density lipoprotein cholesterol (LDL), TC to high-density lipoprotein cholesterol (HDL) ratio, and LDL to HDL ratio. Weight loss achieved while consuming an ER diet with either normal or high protein may improve immunity by partially decreasing proinflammatory monocytes. Associations between MS and plasma lipids and lipoproteins are confirmed in overweight and obese adults.


Assuntos
Restrição Calórica , Dieta Redutora , Lipídeos/sangue , Monócitos/citologia , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Adulto , Idoso , Composição Corporal , Índice de Massa Corporal , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Sobrepeso/sangue , Cooperação do Paciente , Estudos Prospectivos , Receptores de IgG/metabolismo , Estudos Retrospectivos , Redução de Peso
14.
Stem Cells ; 35(5): 1303-1315, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28299842

RESUMO

Electroacupuncture (EA) performed in rats and humans using limb acupuncture sites, LI-4 and LI-11, and GV-14 and GV-20 (humans) and Bai-hui (rats) increased functional connectivity between the anterior hypothalamus and the amygdala and mobilized mesenchymal stem cells (MSCs) into the systemic circulation. In human subjects, the source of the MSC was found to be primarily adipose tissue, whereas in rodents the tissue sources were considered more heterogeneous. Pharmacological disinhibition of rat hypothalamus enhanced sympathetic nervous system (SNS) activation and similarly resulted in a release of MSC into the circulation. EA-mediated SNS activation was further supported by browning of white adipose tissue in rats. EA treatment of rats undergoing partial rupture of the Achilles tendon resulted in reduced mechanical hyperalgesia, increased serum interleukin-10 levels and tendon remodeling, effects blocked in propranolol-treated rodents. To distinguish the afferent role of the peripheral nervous system, phosphoinositide-interacting regulator of transient receptor potential channels (Pirt)-GCaMP3 (genetically encoded calcium sensor) mice were treated with EA acupuncture points, ST-36 and LIV-3, and GV-14 and Bai-hui and resulted in a rapid activation of primary sensory neurons. EA activated sensory ganglia and SNS centers to mediate the release of MSC that can enhance tissue repair, increase anti-inflammatory cytokine production and provide pronounced analgesic relief. Stem Cells 2017;35:1303-1315.


Assuntos
Sistema Nervoso Central/citologia , Eletroacupuntura , Células-Tronco Mesenquimais/citologia , Tendão do Calcâneo/patologia , Pontos de Acupuntura , Adipócitos/citologia , Tecido Adiposo Marrom/citologia , Tecido Adiposo Branco/citologia , Animais , Antígenos CD/metabolismo , Membro Anterior/fisiologia , Membro Posterior/fisiologia , Humanos , Hiperalgesia/terapia , Hipotálamo/citologia , Interleucina-10/sangue , Macrófagos/citologia , Camundongos , Rede Nervosa/fisiologia , Ratos , Ruptura , Células Receptoras Sensoriais/metabolismo , Proteína Desacopladora 1/metabolismo
15.
Free Radic Biol Med ; 97: 212-222, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27266634

RESUMO

Neurofibromatosis type 1 (NF1) predisposes individuals to early and debilitating cardiovascular disease. Loss of function mutations in the NF1 tumor suppressor gene, which encodes the protein neurofibromin, leads to accelerated p21(Ras) activity and phosphorylation of multiple downstream kinases, including Erk and Akt. Nf1 heterozygous (Nf1(+/-)) mice develop a robust neointima that mimics human disease. Monocytes/macrophages play a central role in NF1 arterial stenosis as Nf1 mutations in myeloid cells alone are sufficient to reproduce the enhanced neointima observed in Nf1(+/-) mice. Though the molecular mechanisms underlying NF1 arterial stenosis remain elusive, macrophages are important producers of reactive oxygen species (ROS) and Ras activity directly regulates ROS production. Here, we use compound mutant and lineage-restricted mice to demonstrate that Nf1(+/-) macrophages produce excessive ROS, which enhance Nf1(+/-) smooth muscle cell proliferation in vitro and in vivo. Further, use of a specific NADPH oxidase-2 inhibitor to limit ROS production prevents neointima formation in Nf1(+/-) mice. Finally, mononuclear cells from asymptomatic NF1 patients have increased oxidative DNA damage, an indicator of chronic exposure to oxidative stress. These data provide genetic and pharmacologic evidence that excessive exposure to oxidant species underlie NF1 arterial stenosis and provide a platform for designing novels therapies and interventions.


Assuntos
NADPH Oxidase 2/genética , Neurofibromatose 1/genética , Neurofibromina 1/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Estenose das Carótidas/genética , Estenose das Carótidas/fisiopatologia , Proliferação de Células/genética , Dano ao DNA/genética , Heterozigoto , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , NADPH Oxidase 2/metabolismo , Neointima/genética , Neointima/metabolismo , Neointima/fisiopatologia , Neurofibromatose 1/metabolismo , Neurofibromatose 1/fisiopatologia , Estresse Oxidativo/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Espécies Reativas de Oxigênio/metabolismo
16.
J Hematol Thromb ; 1(1)2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26523291

RESUMO

Radiation during childhood cancer treatment increases the propensity to atherosclerotic cardiovascular disease among adult survivors of childhood cancer. This is thought to be mediated through the damage to the underlying vascular endothelium. Endothelial progenitor cells (EPCs) involved in vascular endothelial repair after its damage may be affected by radiation therapy but have never been investigated in adult survivors of childhood cancer. In this pilot study, utilizing multi-parametric flowcytometry, endothelial colony forming cells (ECFCs), which are the bonafide EPCs, and circulating endothelial cells (CECs), which are not EPCs, were compared between adult survivors of childhood cancer with or without radiation exposure. In addition, their associations with blood-pressure, physical activity and diet were examined. Survivors who received radiotherapy had lower ECFCs and CECs (p<0.05) compared to those without it. Significant positive correlations included physical activity with ECFCs and diet with CECs, while blood-pressure negatively correlated with ECFCs. Further evaluation is needed to examine the effect of radiation and modifiable risk factors on ECFCs and CECs. The preliminary findings from this study suggest evidence of the role of ECFCs as biomarkers of vascular injury following treatment for childhood cancer that may help in early identification of survivors at risk for cardiovascular disease.

17.
J Pediatr Hematol Oncol ; 37(6): 443-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26115508

RESUMO

Utilizing a multiparametric flow cytometry protocol, we assessed various cell types implicated in tumor angiogenesis that were found circulating in the peripheral blood of children with sarcomas (cases) based on their cell surface antigen expression. Circulating endothelial cells (CECs), endothelial colony-forming cells (ECFCs), and the ratio of 2 distinct populations of circulating hematopoietic stem and progenitor cells (CHSPCs), the proangiogenic CHSPCs (pCHSPCs) and nonangiogenic CHSPCs (nCHSPCs) were enumerated. Multiparametric flow cytometry was analyzed in cases at baseline and at 4 additional timepoints until the end of treatment and levels compared with each other and with healthy controls. At all timepoints, cases had significantly lower levels of CECs, but elevated ECFCs and a pCHSPC:nCHSPC ratio compared with controls (all P-values <0.05). There was no significant difference in any of the cell types analyzed based on tumor histology, stage (localized vs. metastatic), or tumor size. After treatment, only the CECs among the complete responders were significantly lower at end of therapy (P<0.01) compared with nonresponders, whereas the ECFCs among all cases significantly increased (P<0.05) compared with baseline. No decline in the pCHSPC:nCHSPC ratio was observed despite tumor response. On the basis of these results, a validation of CECs as prognostic biomarker is now warranted.


Assuntos
Células Endoteliais/patologia , Células-Tronco Hematopoéticas/patologia , Células Neoplásicas Circulantes/patologia , Sarcoma/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Lactente , Estudos Longitudinais , Masculino , Estadiamento de Neoplasias , Projetos Piloto , Prognóstico , Sarcoma/terapia , Adulto Jovem
18.
J Acquir Immune Defic Syndr ; 68(5): 550-3, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25564108

RESUMO

The relationships between HIV infection, monocyte activation, and endothelial colony-forming cells (ECFCs) are unknown. We compared ECFC, intermediate monocytes (CD14 CD16), and nonclassical monocytes (CD14 CD16) levels in HIV-infected participants virologically suppressed on antiretroviral therapy, HIV-infected treatment-naive participants, and HIV-uninfected healthy controls. ECFC levels were significantly higher in the HIV-infected virologically suppressed group compared with the uninfected controls. CD14 CD16 percentages (but not CD14 CD16 cells) were significantly higher in both HIV-infected groups vs. uninfected controls. In the HIV-infected groups, ECFCs and CD14 CD16 intermediate monocytes were significantly and inversely correlated. Lower availability of ECFCs may partly explain the relationship between greater intermediate monocytes and atherosclerosis in HIV.


Assuntos
Células Progenitoras Endoteliais/fisiologia , Infecções por HIV/imunologia , Infecções por HIV/patologia , Monócitos/imunologia , Adulto , Contagem de Células , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
19.
Pediatr Pulmonol ; 50(12): 1313-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25462113

RESUMO

RATIONALE: While infants who are born extremely premature and develop bronchopulmonary dysplasia (BPD) have impaired alveolar development and decreased pulmonary diffusion (DLCO), it remains unclear whether infants born less premature and do not develop BPD, healthy premature (HP), have impaired parenchymal development. In addition, there is increasing evidence that pro-angiogenic cells are important for vascular development; however, there is little information on the relationship of pro-angiogenic cells to lung growth and development in infants. OBJECTIVE: and Methods Determine among healthy premature (HP) and fullterm (FT) infants, whether DLCO and alveolar volume (VA) are related to gestational age at birth (GA), respiratory support during the neonatal period (mechanical ventilation [MV], supplemental oxygen [O2], continuous positive airway pressure [CPAP]), and pro-angiogenic circulating hematopoietic stem/progenitor cells (CHSPCs). We measured DLCO, VA, and CHSPCs in infants between 3-33 months corrected-ages; HP (mean GA = 31.7 wks; N = 48,) and FT (mean GA = 39.3 wks; N =88). RESULT: DLCO was significantly higher in HP than FT subjects, while there was no difference in VA , after adjusting for body length, gender, and race. DLCO and VA were not associated with GA, MV and O2; however, higher values were associated with higher CHSPCs, as well as treatment with CPAP. CONCLUSION: Our findings suggest that in the absence of extreme premature birth, as well as BPD, prematurity per se, does not impair lung parenchymal development.


Assuntos
Recém-Nascido Prematuro/fisiologia , Pulmão/crescimento & desenvolvimento , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Idade Gestacional , Células-Tronco Hematopoéticas/fisiologia , Humanos , Lactente , Recém-Nascido , Masculino , Células-Tronco/fisiologia , Nascimento a Termo
20.
PLoS One ; 9(4): e95694, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24752613

RESUMO

Preventing pathological ocular angiogenesis is key to treating retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration. At present there is no small molecule drug on the market to target this process and hence there is a pressing need for developing novel small molecules that can replace or complement the present surgical and biologic therapies for these neovascular eye diseases. Previously, an antiangiogenic homoisoflavanone was isolated from the bulb of a medicinal orchid, Cremastra appendiculata. In this study, we present the synthesis of a novel homoisoflavanone isomer of this compound. Our compound, SH-11052, has antiproliferative activity against human umbilical vein endothelial cells, and also against more ocular disease-relevant human retinal microvascular endothelial cells (HRECs). Tube formation and cell cycle progression of HRECs were inhibited by SH-11052, but the compound did not induce apoptosis at effective concentrations. SH-11052 also decreased TNF-α induced p38 MAPK phosphorylation in these cells. Intriguingly, SH-11052 blocked TNF-α induced IκB-α degradation, and therefore decreased NF-κB nuclear translocation. It decreased the expression of NF-κB target genes and the pro-angiogenic or pro-inflammatory markers VCAM-1, CCL2, IL8, and PTGS2. In addition SH-11052 inhibited VEGF induced activation of Akt but not VEGF receptor autophosphorylation. Based on these results we propose that SH-11052 inhibits inflammation induced angiogenesis by blocking both TNF-α and VEGF mediated pathways, two major pathways involved in pathological angiogenesis. Synthesis of this novel homoisoflavanone opens the door to structure-activity relationship studies of this class of compound and further evaluation of its mechanism and potential to complement existing antiangiogenic drugs.


Assuntos
Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Isoflavonas/síntese química , Isoflavonas/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Eritropoetina/metabolismo , Humanos , Isoflavonas/química , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
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