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1.
Eur Cardiol ; 17: e15, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35702571

RESUMO

Chest pain is one of the most common presenting symptoms in patients seeking care from a physician. Risk assessment tools and scores have facilitated prompt diagnosis and optimal management in these patients; however, it is unclear as to whether a standardised approach can adequately triage chest pain in cancer patients and survivors. This is of concern because cancer patients are often at an increased risk of cardiovascular mortality and morbidity given the shared risk factors between cancer and cardiovascular disease, compounded by the fact that certain anti-cancer therapies are associated with an increased risk of cardiovascular events that can persist for weeks and even years after treatment. This article describes the underlying mechanisms of the most common causes of chest pain in cancer patients with an emphasis on how their management may differ to that of non-cancer patients with chest pain. It will also highlight the role of the cardio-oncology team, who can aid in identifying cancer therapy-related cardiovascular side-effects and provide optimal multidisciplinary care for these patients.

2.
BMJ Case Rep ; 14(7)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315748

RESUMO

A 51-year-old woman presented with a 2-week history of off balance, left lower limb weakness and neglect and neck pain radiating down the right arm. Investigations revealed a metastatic, ROS1 fusion-positive, non-small cell lung cancer, and treatment with entrectinib, a recently approved multikinase inhibitor, was started. Two weeks after, she was admitted to the emergency department with new-onset pressure-like chest pain and dyspnoea. Laboratory evaluation showed elevated troponin and mild left ventricular systolic dysfunction with reduced global longitudinal strain on transthoracic echocardiogram. Cardiac magnetic resonance revealed mild oedema and non-ischaemic fibrosis. A diagnosis of drug-induced myocarditis was made. Cardioprotective medication with an angiotensin-converting enzyme inhibitor and a beta-blocker was started. Entrectinib was temporarily discontinued and restarted at a reduced dose after a multidisciplinary team meeting involving both the oncology and cardio-oncology teams. This is the second described case of entrectinib-induced myocarditis and the first one without eosinophilia.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Miocardite , Benzamidas , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Feminino , Humanos , Indazóis , Neoplasias Pulmonares/tratamento farmacológico , Pessoa de Meia-Idade , Miocardite/induzido quimicamente , Miocardite/diagnóstico , Proteínas Tirosina Quinases , Proteínas Proto-Oncogênicas
4.
Eur Heart J Cardiovasc Imaging ; 22(4): 397-405, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33555007

RESUMO

Chemotherapy and radiotherapy have drastically improved cancer survival, but they can result in significant short- and long-term cardiovascular complications, most commonly heart failure from chemotherapy, whilst radiotherapy increases the risk of premature coronary artery disease (CAD), valve, and pericardial diseases. Cardiac computed tomography (CT) with calcium scoring has a role in screening asymptomatic patients for premature CAD, cardiac CT angiography (CTCA) allows the identification of significant CAD, also in the acute settings where concerns exist towards invasive angiography. CTCA integrates the diagnostic work-up and guides surgical/percutaneous management of valvular heart diseases and allows the assessment of pericardial conditions, including detection of effusion and pericardial calcification. It is a widely available and fast imaging modality that allows a one-step evaluation of CAD, myocardial, valvular, and pericardial disease. This review aims to provide an update on its current use and accompanying evidence-base for cardiac CT in the management of cardio-oncology patients.


Assuntos
Doença da Artéria Coronariana , Neoplasias , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Humanos , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada por Raios X
5.
Curr Cardiol Rep ; 23(3): 16, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33501515

RESUMO

PURPOSE OF REVIEW: Cardiotoxicity can occur acutely during breast cancer treatment and impact the potential for the intended cancer treatment regime to be completed, or as a late effect affecting cancer survivorship. Indeed, the most common cause of mortality in females with early breast cancer is cardiovascular disease, especially in those over the age of 65. Optimal cancer care therefore needs to be delivered without jeopardising cardiovascular health. Understanding the different cardiotoxicities associated with breast cancer treatment is vital to this approach, and therefore, this article seeks to provide an overview of this. RECENT FINDINGS: Tyrosine kinase inhibitors targeting human epidermal growth factor receptor (HER)-2, immune checkpoint inhibitors (ICI), and cyclin-dependent kinase (CDK) inhibitors are new targeted breast cancer treatments. In particular, ICI are associated with myocarditis that carries a significant mortality, whilst the CDK inhibitor ribociclib causes QT prolongation that requires cardiac surveillance and appropriate dose adjustment to prevent ventricular arrhythmias. The need has always been for strategies to mitigate the risks of cardiovascular toxicities, and new data is promising for the use of dexrazoxane in anthracyclines, and the role of beta blockers and angiotensin converting enzymes inhibitors in anthracyclines and HER-2 monoclonal antibodies such as trastuzumab. Significant headways in breast cancer treatment have resulted in reductions in disease recurrence and mortality, but cardiovascular complications continue to impact the ability to deliver some of these cancer treatments, and the period of cancer survivorship.


Assuntos
Antineoplásicos , Neoplasias da Mama , Doenças Cardiovasculares , Antraciclinas , Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Doenças Cardiovasculares/induzido quimicamente , Feminino , Humanos , Recidiva Local de Neoplasia , Trastuzumab/efeitos adversos
6.
Ann Plast Surg ; 85(S1 Suppl 1): S102-S108, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32187068

RESUMO

BACKGROUND: Over the past decade, the demand for breast reconstruction has mirrored the rising incidence of breast cancer. Common postoncologic surgical options include autologous and implant-based reconstruction. Patient-directed health information for breast reconstruction can play a critical role in the decision-making process. This study comparatively evaluates the top online resources for autologous versus implant-based reconstruction using a multimetric health literacy analysis. METHODS: The top 10 websites for autologous and implant-based reconstruction were identified using a Google search. A total of 20 unique links were appraised by 2 independent raters for understandability and actionability using the Patient Education Materials Assessment Tool and cultural sensitivity using the Cultural Sensitivity Assessment Tool. A Cohen κ for interrater reliability was calculated. Mean reading grade level and word complexity were also determined. RESULTS: Websites for both autologous and implant-based modalities exceeded the recommended sixth- to eighth-grade reading level (12.4 and 12.1, respectively; P = 0.65). Mean understandability scores for each modality were low (60.5 and 62.5, P = 0.65). Autologous-based resources had a lower mean actionability score compared with implant-based materials (19.5 and 24, respectively; P = 0.04). Both reconstructive modalities met the threshold for acceptability for cultural sensitivity (2.79 and 2.58, P = 0.09). CONCLUSIONS: Our study revealed a chasm between the health literacy needs of the average adult and the quality of both implant-based and autologous breast reconstruction resources. Materials for both modalities were often too complex and failed to include tools to facilitate active decision making, particularly for autologous-based reconstruction. Strategies to improve materials should be patient centered and include simplification of reading grade level, incorporation of clear visual aids, and inclusion of procedural risks to promote patient comprehension, participation, and ultimately health outcomes.


Assuntos
Neoplasias da Mama , Letramento em Saúde , Mamoplastia , Neoplasias da Mama/cirurgia , Compreensão , Humanos , Internet , Reprodutibilidade dos Testes
7.
JACC CardioOncol ; 2(1): 97-109, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34396213

RESUMO

CD19-specific chimeric antigen receptor (CAR) T cell therapies have shown remarkable early success in highly refractory and relapsing hematological malignancies. However, this potent therapy is accompanied by significant toxicity. Cytokine release syndrome and neurotoxicity are the most widely reported, but the true extent and characteristics of cardiovascular toxicity remain poorly understood. Thus far, adverse cardiovascular effects observed include sinus tachycardia and other arrhythmias, left ventricular systolic dysfunction, profound hypotension, and shock requiring inotropic support. The literature regarding cardiovascular toxicities remains sparse; prospective studies are needed to define the cardiac safety of CAR T cell therapies to optimally harness their potential. This review summarizes the current understanding of the potential cardiovascular toxicities of CD19-specific CAR T cell therapies, outlines a proposed cardiac surveillance protocol for patients receiving this new treatment, and provides a roadmap of the future direction of cardio-oncology research in this area.

8.
World Neurosurg ; 123: e379-e386, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30500589

RESUMO

OBJECTIVE: Anterior column realignment (ACR) is a new emerging minimally invasive surgical technique for adult spinal deformity (ASD) that has the potential to provide similar corrective ability to traditional posterior approaches. This article reviews the current literature on the clinical efficacy and safety of ACR and illustrates an additional use of this technique in a case of sagittal imbalance after posterior spinal fusion with segmental instrumentation. METHODS: We performed a literature search of all published ACR reports using PubMed, including only clinical studies describing the ACR technique and reporting radiographic and/or clinical outcomes. RESULTS: Thirteen studies were included. Improvement in lumbar lordosis after ACR ranged from 12.7° to 39°, and increases in focal segmental lordosis at each ACR level ranged from 1° to 34°. Good clinical and functional outcomes have consistently been reported after ACR. The complication rate has been comparable to or lower than traditional posterior-based techniques. We also illustrate the use of ACR in a patient with sagittal imbalance after a prior posterior instrumented spinal fusion. ACR in combination with a posterior osteotomy allowed for the induction of lordosis by cantilevering of rods and compression of pedicle screws. CONCLUSIONS: Radiographic and clinical outcomes after ACR have been promising so far. In addition to primary ASD surgery, ACR can also be effectively used in cases with prior posterior instrumented spinal fusion to correct sagittal imbalance.


Assuntos
Lordose/cirurgia , Osteotomia/métodos , Fusão Vertebral/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco , Vértebras Torácicas/cirurgia , Resultado do Tratamento
9.
J Air Waste Manag Assoc ; 69(1): 119-130, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30230968

RESUMO

Flares are important safety devices for pressure relief; at the same time, flares are a significant point source for soot and highly reactive volatile organic compounds (HRVOCs). Currently, simple guidelines for flare operations to maintain high combustion efficiency (CE) remain elusive. This paper fills the gap by investigating the characteristics of the incipient smoke point (ISP), which is widely recognized as the condition for good combustion. This study characterizes the ISP in terms of 100-% combustion inefficiency (CE), percent opacity, absorbance, air assist, steam assist, air equivalence ratio, steam equivalence ratio, exit velocity, vent gas net heating value, and combustion zone net heating value. Flame lengths were calculated for buoyant and momentum-dominated plumes under calm and windy conditions at stable and neutral atmosphere. Opacity was calculated using the Beer-Lambert law based on soot concentration, flame diameter, and mass-specific extinction cross section of soot. The calculated opacity and absorbance were found to be lognormally distributed. Linear relations were established for soot yield versus absorptivity with R2 > 0.99 and power-law relations for opacity versus soot emission rate with R2 ≥ 0.97 for steam-assisted, air-assisted, and nonassisted flares. The characterized steam/air assists, combustion zone/vent gas heating values, exit velocity, steam, and air equivalence ratios for the incipient smoke point will serve as a useful guideline for efficient flare operations.Implications: A Recent EPA rule requires an evaluation of visible emissions in terms of opacity in compliance with the standards. In this paper, visible emissions such as soot particles are characterized in terms of opacity at ISP. Since ISP is widely recognized as most efficient flare operation for high combustion efficiency (CE)/destruction efficiency (DE) with initial soot particles formed in the flame, this characterization provides a useful guideline for flare operators in the refinery, oil and gas, and chemical industries to sustain smokeless and high combustion efficiency flaring in compliance with recent EPA regulations, in addition to protecting the environment.


Assuntos
Poluentes Atmosféricos/análise , Fumaça/análise , Fuligem/análise , Compostos Orgânicos Voláteis/análise , Indústria Química , Vapor
10.
Sci Rep ; 7(1): 13480, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29044151

RESUMO

Usher syndrome type III (USH3) characterized by progressive loss of vision and hearing is caused by mutations in the clarin-1 gene (CLRN1). Clrn1 knockout (KO) mice develop hair cell defects by postnatal day 2 (P2) and are deaf by P21-P25. Early onset profound hearing loss in KO mice and lack of information about the cochlear cell type that requires Clrn1 expression pose challenges to therapeutic investigation. We generated KO mice harboring a transgene, TgAC1, consisting of Clrn1-UTR (Clrn1 cDNA including its 5' and 3' UTR) under the control of regulatory elements (Atoh1 3' enhancer/ß-globin basal promoter) to direct expression of Clrn1 in hair cells during development and down regulate it postnatally. The KO-TgAC1 mice displayed delayed onset progressive hearing loss associated with deterioration of the hair bundle structure, leading to the hypothesis that hair cell expression of Clrn1 is essential for postnatal preservation of hair cell structure and hearing. Consistent with that hypothesis, perinatal transfection of hair cells in KO-TgAC1 mice with a single injection of AAV-Clrn1-UTR vector showed correlative preservation of the hair bundle structure and hearing through adult life. Further, the efficacy of AAV-Clrn1 vector was significantly attenuated, revealing the potential importance of UTR in gene therapy.


Assuntos
Perda Auditiva/diagnóstico , Perda Auditiva/etiologia , Síndromes de Usher/complicações , Animais , Sequência de Bases , Dependovirus/genética , Modelos Animais de Doenças , Expressão Gênica , Ordem dos Genes , Vetores Genéticos/genética , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/ultraestrutura , Perda Auditiva/prevenção & controle , Humanos , Imuno-Histoquímica , Proteínas de Membrana/química , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Especificidade de Órgãos , Fenótipo , Transporte Proteico , Transdução Genética , Síndromes de Usher/diagnóstico , Síndromes de Usher/etiologia
11.
J Air Waste Manag Assoc ; 67(5): 599-612, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27996695

RESUMO

Emissions from flares constitute unburned hydrocarbons, carbon monoxide (CO), soot, and other partially burned and altered hydrocarbons along with carbon dioxide (CO2) and water. Soot or visible smoke is of particular concern for flare operators/regulatory agencies. The goal of the study is to develop a computational fluid dynamics (CFD) model capable of predicting flare combustion efficiency (CE) and soot emission. Since detailed combustion mechanisms are too complicated for (CFD) application, a 50-species reduced mechanism, LU 3.0.1, was developed. LU 3.0.1 is capable of handling C4 hydrocarbons and soot precursor species (C2H2, C2H4, C6H6). The new reduced mechanism LU 3.0.1 was first validated against experimental performance indicators: laminar flame speed, adiabatic flame temperature, and ignition delay. Further, CFD simulations using LU 3.0.1 were run to predict soot emission and CE of air-assisted flare tests conducted in 2010 in Tulsa, Oklahoma, using ANSYS Fluent software. Results of non-premixed probability density function (PDF) model and eddy dissipation concept (EDC) model are discussed. It is also noteworthy that when used in conjunction with the EDC turbulence-chemistry model, LU 3.0.1 can reasonably predict volatile organic compound (VOC) emissions as well. IMPLICATIONS: A reduced combustion mechanism containing 50 C1-C4 species and soot precursors has been developed and validated against experimental data. The combustion mechanism is then employed in the computational fluid dynamics (CFD) of modeling of soot emission and combustion efficiency (CE) of controlled flares for which experimental soot and CE data are available. The validated CFD modeling tools are useful for oil, gas, and chemical industries to comply with U.S. Environmental Protection Agency's (EPA) mandate to achieve smokeless flaring with a high CE.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Hidrodinâmica , Modelos Químicos , Fuligem/análise , Incêndios , Temperatura , Compostos Orgânicos Voláteis/análise
12.
Laryngoscope ; 118(4): 692-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18094649

RESUMO

OBJECTIVES: Fine needle aspiration (FNA) biopsy of thyroid nodules provides cytologic specimens whose interpretation can direct patients toward either thyroidectomy or observation. Approximately 20% of FNA specimens yield an indeterminate result. Recent studies have characterized differences in gene expression between benign and malignant conditions, most often using whole tissue. Our goal was to determine the feasibility of quantitative polymerase chain reaction (qPCR)-based gene expression analysis in cytologic samples. For five genes shown to be over-expressed in thyroid carcinomas (fibronectin, galectin-3, Met/HGFR, MUC1, and GA733-precursor), we compared expression among pathologic states. STUDY DESIGN: Prospective laboratory analysis of 20 thyroidectomy specimens. METHODS: Routine microscopy was performed. Cytologic samples were obtained from the dominant nodules, and RNA was extracted. Preliminary analysis using fluorometry and reverse-transcriptase (RT)-PCR was performed. Expression levels of the test genes in nodules and from control samples were measured by real-time qPCR. Fold changes in gene expression were compared. RESULTS: Only one specimen did not yield sufficient intact RNA for gene expression analysis. RT-PCR revealed satisfactory RNA recovery in all other specimens. qPCR showed significant over-expression of fibronectin in the papillary carcinomas compared with the goiters (P = .0013), follicular adenomas (P = .0014), and follicular carcinomas (P = .0001). Differences in both fibronectin and MUC1 expression between the follicular carcinomas and the follicular adenomas were also significant (P = .025 and .045, respectively). CONCLUSIONS: Cytologic specimens were a satisfactory source of tissue for qPCR-based gene expression analysis. Both fibronectin and MUC1 were differentially expressed in follicular adenomas and follicular carcinomas, and fibronectin expression differed in papillary carcinomas compared with the other lesions. These results may form the basis of a clinical predictor for lesions with indeterminate or suspicious cytology.


Assuntos
Nódulo da Glândula Tireoide/patologia , Adenocarcinoma Folicular/patologia , Adenoma/patologia , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Biópsia por Agulha Fina , Complexo CD3/análise , Carcinoma Papilar/patologia , Moléculas de Adesão Celular/análise , Molécula de Adesão da Célula Epitelial , Estudos de Viabilidade , Fibronectinas/análise , Galectina 3/análise , Regulação Neoplásica da Expressão Gênica/genética , Bócio/patologia , Humanos , Biologia Molecular , Mucina-1/análise , Reação em Cadeia da Polimerase , Estudos Prospectivos , Proteínas Tirosina Quinases/análise , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-met , Receptores de Fatores de Crescimento/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/patologia
13.
Dev Neurosci ; 29(3): 251-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17047322

RESUMO

Genetic, noise- and drug-induced loss of hair cells in the mouse and human cochlea leads to permanent hearing loss due to lack of regeneration of hair cells, which may be due to reduced numbers or loss of the regenerative ability of stem cells in the adult cochlea. We hypothesized that the mouse neonate cochlea harbors stem cells capable of differentiating into hair cells. Cells from the primary neonate cochlear culture began to proliferate and formed floating spheres after 14 days in vitro (DIV). By comparison, spheres from the primary culture of the cortex were observed after 7 DIV. Cochlear sphere cells could be passaged and the new spheres were observed after 7 DIV. Cochlear sphere cells were capable of differentiating into astrocytes and oligodendrocytes, but not neurons under the conditions tested. Cochlear sphere cells expressed Sox2 and Myo7a, but failed to show markers that are expressed exclusively in mature cochlear tissue, while cells from cortex spheres expressed Sox2 and Otx2, but not Myo7a. Our results show that cochleae from neonatal mice harbor cells capable of forming spheres and cells from these spheres appear to be better endowed to become hair cells.


Assuntos
Cóclea/citologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco/citologia , Fatores Etários , Animais , Animais Recém-Nascidos , Cóclea/fisiologia , Dineínas/genética , Células Ciliadas Auditivas/citologia , Proteínas de Homeodomínio/genética , Proteínas de Filamentos Intermediários/genética , Camundongos , Camundongos Endogâmicos C57BL , Miosina VIIa , Miosinas/genética , Proteínas do Tecido Nervoso/genética , Nestina , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares , Células-Tronco/fisiologia , Fator de Transcrição Brn-3C/genética
14.
Brain Res ; 1091(1): 289-99, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16529721

RESUMO

Laser Capture Microdissection (LCM) allows microscopic procurement of specific cell types from tissue sections that can then be used for gene expression analysis. We first tested this method with sections of adult mouse inner ears and subsequently applied it to human inner ear sections. The morphology of the various cell types within the inner ear is well preserved in formalin fixed paraffin embedded (FFPE) sections, making it easier to identify cell types and their boundaries. Recovery of good quality RNA from FFPE sections can be challenging, however, recent studies in cancer research demonstrated that it is possible to carry out gene expression analysis of FFPE material. Thus, a method developed using mouse FFPE tissue can be applied to human archival temporal bones. This is important because the majority of human temporal bone banks have specimens preserved in formalin and a technique for retrospective analysis of human archival ear tissue is needed. We used mouse FFPE inner ear sections to procure distinct populations of cells from the various functional domains (organ of Corti, spiral ganglion, etc.) by LCM. RNA was extracted from captured cells, amplified, and assessed for quality. Expression of selected genes was tested by RT-PCR. In addition to housekeeping genes, we were able to detect cell type specific markers, such as Myosin 7a, p27(kip1) and neurofilament gene transcripts that confirmed the likely composition of cells in the sample. We also tested the method described above on FFPE sections from human crista ampullaris. These sections were approximately a year old. Populations of cells from the epithelium and stroma were collected and analyzed independently for gene expression. The method described here has potential use in many areas of hearing research. For example, following exposure to noise, ototoxic drugs or age, it would be highly desirable to analyze gene expression profiles of selected populations of cells within the organ of Corti or spiral ganglion cells rather than a mixed population of cells from whole inner ear tissue. Also, this method can be applied for analysis of human archival ear tissue.


Assuntos
Orelha Interna/metabolismo , Expressão Gênica/fisiologia , Lasers , Microdissecção/métodos , Inclusão em Parafina/métodos , Animais , Contagem de Células/métodos , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Dineínas/genética , Dineínas/metabolismo , Orelha Interna/anatomia & histologia , Humanos , Hibridização In Situ/métodos , Camundongos , Miosina VIIa , Miosinas/genética , Miosinas/metabolismo , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fixação de Tecidos/métodos
15.
BJU Int ; 94(4): 637-50, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15329129

RESUMO

OBJECTIVES: To investigate, in an initial study, the use of microarray analysis (MA) to develop an information base for urolithiasis. MA enables the screening of thousands of genes simultaneously making it the technique of choice for situations where the results are known, but the underlying mechanisms are not. Little is known about the pathological changes occurring in the kidney during urolithiasis and this has severely hampered efforts to develop effective therapeutics. MATERIALS AND METHODS: Male rats were treated with 0.75% ethylene glycol for 2, 4 or 8 weeks; after death the kidneys were processed for RNA isolation and MA, conducted using a rat-based chip (one kidney/chip) and the results confirmed by reverse transcription-polymerase chain reaction (RT-PCR, 21 probe sets; control, four rats; treated, five rats). Targets were defined as different by the software if the fold change (FC) was >or= 2, and sorted into functional categories using a data-mining tool. The repeatability of MA was investigated by subjecting the 4-week samples to MA in two independent runs. RESULTS: The results for targets with a FC of >or= 2 were plotted (y = 1.01x - 0.75; r(2) 0.84). Comparing the results obtained by RT-PCR and MA showed a good qualitative correlation for those targets having a FC of >or= 5 as determined by MA. Changes in the expression of genes associated with tubule function and regulation, oxidative damage, and inflammation were the most common in the functional categories. Changes in the expression of tubule-specific markers indicated that there was damage to the proximal (gamma-adducin, organic anion and cation transporters, sodium-hydrogen exchange protein-isoform 3) and distal tubules (gamma-adducin, kallikrein) at 2 and 4 weeks. Increased expression of mitochondrial uncoupling protein indicated that there were changes to the mitochondria and oxidative stress at 2 and 4 weeks. CONCLUSION: This study shows the power of MA as an exploratory technique, and changes in the expression of several physiologically important genes whose expression has not previously been reported to be affected by hyperoxaluria or calcium oxalate crystalluria.


Assuntos
Etilenoglicol/toxicidade , Cálculos Renais/genética , Fenótipo , Animais , Cálculos Renais/induzido quimicamente , Masculino , Análise Serial de Proteínas/métodos , RNA/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
16.
J Urol ; 171(3): 1304-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14767338

RESUMO

PURPOSE: Unraveling the mechanisms leading to clinically active calcium oxalate (CaOx) stone disease and the development of effective medical therapies to treat it have been hampered by the lack of appropriate animal models. To address this problem we developed a model of hyperoxaluria and calcium oxalate crystal deposition by implanting osmotic minipumps subcutaneously into male rats, that is minipump induced hyperoxaluria and crystal deposition in rats. MATERIALS AND METHODS: Male Harlan-Sprague Dawley rats (225 to 290 gm) were implanted subcutaneously with 1-week 2 ml osmotic minipumps containing 1.5 M potassium oxalate (360 microM KOx/24 hours, [KOx-trt], 11) or phosphate buffered saline (PBS-trt, 9) on days 1 and 7. The 24-hour urine collections were performed on days 0, 4, 7, 11 and 14. Data were analyzed by ANOVA and Tukey's HSD. Urinary crystals were analyzed by light microscopy. Kidneys were harvested on day 14 and processed for light and polarizing microscopy, and RNA analysis.RESULTS Mean overall creatinine excretion +/- SEM (PBS-trt 107 +/- 7 and KOx-trt 123 +/- 6 microM/24 hours, p >0.07) and day 14 serum creatinine (PBS-trt 83 +/- 4 and KOx-trt 83 +/- 5 microM, p >or=0.9) were similar in the 2 treatment groups. Overall urinary volume (PBS-trt 11.3 +/- 0.8 and KOx-trt 18.0 +/- 1.5 ml/24 hours, p

Assuntos
Oxalato de Cálcio/análise , Modelos Animais de Doenças , Hiperoxalúria/etiologia , Cálculos Renais/química , Cálculos Renais/urina , Animais , Cristalização , Bombas de Infusão , Cálculos Renais/etiologia , Masculino , Ratos , Ratos Sprague-Dawley
17.
J Urol ; 167(5): 2192-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11956477

RESUMO

PURPOSE: Tamm-Horsfall protein is believed to inhibit calcium oxalate crystallization, aggregation or adhesion to the renal epithelium. We determined whether ethylene glycol induced urolithiasis changes the expression of renal and urinary Tamm-Horsfall protein. For comparison the expression of another calcium oxalate inhibitor, osteopontin, was also analyzed. MATERIALS AND METHODS: Male rats were treated with 0.75% ethylene glycol plus an AIN-76 diet (Dyets, Bethlehem Pennsylvania) (ethylene glycol group) or standard rat chow and water (control group) for up to 8 weeks (6 per group for 8 weeks and 3 per group for 3 days to 6 weeks). Kidneys and urine (8 weeks only) were harvested and analyzed by Northern and Western blot analysis, and immunohistochemistry. RESULTS: Tamm-Horsfall protein message and protein (membrane bound form) were decreased, while those of osteopontin were increased in the kidneys of rats treated with ethylene glycol for 8 weeks. As judged by immunochemistry Tamm-Horsfall protein and osteopontin were consistently present in a few tubules in rats in the ethylene glycol and control groups, respectively. In urine expression of the free form of Tamm-Horsfall protein (approximately 75 kDa.) was decreased but detectable in ethylene glycol treated rats. Although readily detected in tissue, osteopontin was not detected in the urine of control or ethylene glycol treated rats. In the time course experiment Tamm-Horsfall protein did not decrease until 4 weeks, when calcium oxalate crystals were detectable in the kidneys of treated rats. In contrast, osteopontin was increased, although inconsistently, beginning at 3 days. CONCLUSIONS: Unlike other calcium oxalate inhibitors, such as osteopontin, renal message and protein for Tamm-Horsfall protein was decreased in ethylene glycol treated rats. Tamm-Horsfall protein expression did not decrease until aggregates of crystals had been deposited in the kidneys, while osteopontin expression began to increase almost immediately. Comparisons of the data on kidneys and urine obtained by RNA or protein blot analysis and immunochemistry underscore the need to examine tissue and urine by multiple techniques to obtain the most accurate assessment of how protein expression is changed by a given treatment.


Assuntos
Oxalato de Cálcio/urina , Cálculos Renais/genética , Rim/patologia , Mucoproteínas/genética , Animais , Etilenoglicol , Feminino , Expressão Gênica/efeitos dos fármacos , Cálculos Renais/induzido quimicamente , Cálculos Renais/patologia , Masculino , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Uromodulina
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