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1.
Biochim Biophys Acta ; 1841(4): 505-13, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24406902

RESUMO

Phospholipid remodeling involves phospholipase activity to remove acyl chains and acyltransferases to replace acyl chains. We here describe the characterization of a lysophospholipid acyltransferase in the opportunistic fungal pathogen, Candida albicans. Expression of this gene, C.a. LPT1, complemented the lysophospholipid acyltransferase defect in Saccharomyces cerevisiae strains lacking the homologous LPT1 gene. In vitro, lysophospholipid acyltransferase activity in these strains showed acyl-CoA substrate specificity, as measured by apparent Vmax/Km ratios, to be linolenoyl-CoA>oleoyl-CoA>linoleoyl-CoA>stearoyl-CoA. To address the physiological importance of C.a. LPT1, homozygous deletion strains were generated. Lysophospholipid acyltransferase activity with amine containing lysophospholipids was dramatically reduced while lysophosphatidylinositol and lysophosphatidic acid esterification was not significantly lowered. However, C.a. LPT1 over-expression yielded an increased amount of lysophosphatidic acyltransferase activity, suggesting a role in de novo phospholipid synthesis. LPT1 deletion strains showed slightly slowed growth in standard liquid media but no phenotype in media containing three antifungals that target sterols. To assess the role of C.a. Lpt1 in phospholipid remodeling, an in vivo, pulse-chase assay utilizing polysorbitan palmitate and mass spectrometry was developed. Cellular phospholipid composition became atypical with the provision of palmitate and gradually returned to the typical distribution when palmitate was removed. Deletion of C.a. LPT1 showed a modest yet significant effect on remodeling under these conditions.


Assuntos
1-Acilglicerofosfocolina O-Aciltransferase/genética , Candida albicans/enzimologia , Membrana Celular/metabolismo , Lisofosfolipídeos/metabolismo , 1-Acilglicerofosfocolina O-Aciltransferase/biossíntese , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Acil Coenzima A/metabolismo , Membrana Celular/química , Membrana Celular/enzimologia , Regulação Fúngica da Expressão Gênica , Lisofosfolipídeos/biossíntese , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato
2.
Nicotine Tob Res ; 16(6): 864-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24401731

RESUMO

INTRODUCTION: U.S. smoking prevalence has been declining over the last several decades. During this time, the population has also experienced changes in its demographic composition, as Americans are living longer and becoming increasingly racially and ethnically diverse. Since smoking rates vary across age and race/ethnicity groups, demographics alone could contribute to changes in smoking prevalence among the general population. We examined the effect of changing age and race/ethnicity distributions on total smoking prevalence from 1980 to 2010. METHODS: Using the National Health Interview Survey weighting scheme, we applied the distribution of smokers across age and race/ethnicity categories for the years 1980 and 2010 to the distribution of adults in those categories for both years. The total number of smokers was summed to determine resulting smoking prevalence. RESULTS: The combined effect of aging and the changing racial/ethnic composition of the U.S. population has contributed 2.1% points to the decline in smoking prevalence. If the age and racial/ethnic demographic composition had not changed since 1980, smoking prevalence would have been 21.3% in 2010 (with rounding)--statistically significantly higher than the reported 19.3%. Of the 3 demographic factors we considered (age, race, and ethnicity), ethnicity--specifically the rising share of Hispanics in the population--is the most important contributor to declines in smoking. CONCLUSIONS: Our changing demographics have had an impact on smoking prevalence over the last 3 decades. Future declines in smoking may be driven even more by the aging of the population and increasing racial and ethnic diversity.


Assuntos
Vigilância da População , Fumar/etnologia , Fumar/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Demografia , Etnicidade/estatística & dados numéricos , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Grupos Raciais/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
3.
ACS Appl Mater Interfaces ; 16(2): 2692-2703, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38173339

RESUMO

As the need for high-speed electronics continues to rise rapidly, printed wiring board (PWB) requirements become ever-more demanding. A typical PWB is fabricated by bonding dielectric films such as polyimide to electrically conductive copper foil such as rolled annealed (RA) copper and is expected to become thinner, flexible, durable, and compatible with high-frequency 5G performance. Polyimide films inherently feature a higher coefficient of thermal expansion (CTE) than copper foils; this mismatch causes residual thermal stresses. To attenuate the mismatch, silica nanoparticles may be used to reduce the CTE of PI. A nodulated copper surface can be used to enhance the Cu/PI adhesion by additional bonding mechanisms that could include a type of mechanical bonding, which is a focus of this study. In this investigation, a 90° peel test was used to measure the peel strength in copper/polyimide/copper laminates containing nodulated copper and polyimide reinforced with 0, 20, and 40 wt % silica nanoparticles. The influence of silica nanoparticles on the peel strength was quantitatively evaluated. Laminates incorporating polyimide films lacking silica nanoparticles had a ∼3.75× higher peel strength compared with laminates reinforced with 40% silica. Their failure surfaces were analyzed by using scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy to identify the mode of failure and to understand bonding mechanisms. The key bonding mechanism, mechanical interlocking, was achieved when the polyimide surrounded or engulfed the copper nodules when the laminate was created. Post-testing failure surface analysis revealed the presence of copper on the polyimide side and polyimide on the copper side, indicating mixed mode failure. An analytical model was developed to determine the impact of applied pressure, temperature, and time on the polyimide penetration and mechanical interlocking around the copper nodules. The model was validated by measuring the peel strength on another set of specimens fabricated using increased temperature and pressure that showed a 3× increase in peel strength compared to lower temperature/pressure processing conditions. This enhanced adhesion resulted from the lower polymer material viscosity at higher temperatures, which fosters deeper and more complete penetration around the copper nodules during processing at higher pressures for longer durations. The methodology of combining peel testing, viscosity and CTE measurement, SEM/EDX, surface chemical analysis, and penetration depth calculation developed herein enables the calculation of the desired processing parameters to enhance functionality and improve adhesion.

4.
Nat Genet ; 32 Suppl: 509-14, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12454646

RESUMO

Measurement of gene-expression profiles using microarray technology is becoming increasingly popular among the biomedical research community. Although there has been great progress in this field, investigators are still confronted with a difficult question after completing their experiments: how to validate the large data sets that are generated? This review summarizes current approaches to verifying global expression results, discusses the caveats that must be considered, and describes some methods that are being developed to address outstanding problems.


Assuntos
Perfilação da Expressão Gênica/normas , Análise de Sequência com Séries de Oligonucleotídeos/normas , Animais , DNA Complementar/genética , Previsões , Perfilação da Expressão Gênica/métodos , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Proteínas/genética , Controle de Qualidade , RNA Mensageiro/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Curr Med Res Opin ; 38(1): 7-18, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34632887

RESUMO

OBJECTIVE: Global treatment guidelines recommend treatment with oral anticoagulants (OACs) for patients with non-valvular atrial fibrillation (NVAF) and an elevated stroke risk. However, not all patients with NVAF and an elevated stroke risk receive guideline-recommended therapy. A literature review and synthesis of observational studies were undertaken to identify the body of evidence on untreated and undertreated NVAF and the association with clinical and economic outcomes. METHODS: An extensive search (1/2010-4/2020) of MEDLINE, the Cochrane Library, conference proceedings, and health technology assessments (HTAs) was conducted. Studies must have evaluated rates of nontreatment or undertreatment in NVAF. Nontreatment was defined as absence of OACs (but with possible antiplatelet treatment), while undertreatment was defined as treatment with only antiplatelet agents. RESULTS: Sixteen studies met our inclusion criteria. Rates of nontreatment for patients with elevated stroke risk ranged from 2.0-51.1%, while rates of undertreatment ranged from 10.0-45.1%. The clinical benefits of anticoagulation were reported in the evaluated studies with reductions in stroke and mortality outcomes observed among patients treated with anticoagulants compared to untreated or undertreated patients. Adverse events associated with all bleeding types (i.e. hemorrhagic stroke, major bleeding or gastrointestinal hemorrhaging) were found to be higher for warfarin patients compared to untreated patients in real-world practice. Healthcare resource utilization was found to be lower among patients highly-adherent to warfarin compared to untreated patients. CONCLUSIONS: Rates of nontreatment and undertreatment among NVAF patients remain high and are associated with preventable cardiovascular events and death. Strategies to increase rates of treatment may improve clinical outcomes.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Administração Oral , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Varfarina/uso terapêutico
6.
Circulation ; 122(13): 1265-71, 2010 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-20837894

RESUMO

BACKGROUND: The Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) showed a significant 31 reduction in the risk of death with primary implantable cardioverter-defibrillator (ICD) therapy during a median follow-up of 1.5 years. However, currently there are no data on the long-term efficacy of primary defibrillator therapy. METHODS AND RESULTS: MADIT-II enrolled 1232 patients with ischemic left ventricular dysfunction who were randomized to ICD and non-ICD medical therapy and were followed up through November 2001. For the present long-term study, we acquired posttrial mortality data through March 2009 for all study participants (median follow-up, 7.6 years). Multivariate Cox proportional hazards regression modeling was performed to calculate the hazard ratio for ICD versus non-ICD therapy during long-term follow-up. At 8 years of follow-up, the cumulative probability of all-cause mortality was 49 among patients treated with an ICD compared with 62 among non-ICD patients (P<0.001). Multivariate analysis demonstrated that ICD therapy was associated with a significant long-term survival benefit (hazard ratio for 0- through 8-year mortality=0.66 [95 confidence interval, 0.56 to 0.78]; P<0.001). Treatment with an ICD was shown to be associated with a significant reduction in the risk of death during the early phase of the extended follow-up period (0 through 4 years: hazard ratio=0.61 [95 confidence interval, 0.50 to 0.76]; P<0.001) and with continued life-saving benefit during the late phase of follow-up (5 through 8 years: hazard ratio=0.74 [95 confidence interval, 0.57 to 0.96]; P=0.02). CONCLUSIONS: Our findings demonstrate a sustained 8-year survival benefit with primary ICD therapy in the MADIT-II population.


Assuntos
Desfibriladores Implantáveis , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/terapia , Idoso , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
7.
Nature ; 433(7023): E5-6; discussion E7-8, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15662370

RESUMO

The idea that natural selection on genes might be detected using only a single genome has been put forward by Plotkin and colleagues, who present a method that they claim can detect selection without the need for comparative data and which, if correct, would confer greater power of analysis with less information. Here we argue that their method depends on assumptions that confound their conclusions and that, even if these assumptions were valid, the authors' inferences about adaptive natural selection are unjustified.


Assuntos
Evolução Biológica , Códon/genética , Genoma Bacteriano , Genômica/métodos , Seleção Genética , Viés , Modelos Genéticos , Mutação de Sentido Incorreto/genética , Mycobacterium tuberculosis/genética , Reprodutibilidade dos Testes
8.
J Arrhythm ; 37(4): 1077-1085, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34386135

RESUMO

INTRODUCTION: Detection of atrial fibrillation (AF) is required to initiate oral anticoagulation (OAC) after cryptogenic stroke (CS). However, paroxysmal AF can be difficult to diagnose with short term cardiac monitoring. Taking an Australian payer perspective, we evaluated whether long-term continuous monitoring for 3 years with an insertable cardiac monitor (ICM) is cost-effective for preventing recurrent stroke in patients with CS. METHODS: A lifetime Markov model was developed to simulate the follow-up of patients, comparing long-term continuous monitoring with an ICM to monitoring by conventional care. We used a linked evidence approach to estimate the rates of recurrent stroke when AF detection leads to initiation of OAC, as detected using ICM during the lifetime of the device or as detected using usual care. All diagnostic and patient management costs were modeled. Other model inputs were determined by literature review. Probabilistic sensitivity analysis (PSA) was undertaken to explore the effect of parameter uncertainty according to CHADS2 score and OAC treatment effect. RESULTS: In the base-case analysis, the model predicted an incremental cost-effectiveness ratio (ICER) of A$29 570 per quality-adjusted life year (QALY). Among CHADS2 subgroups analyses, the ICER ranged from A$26 342/QALY (CHADS2 = 6) to A$42 967/QALY (CHADS2 = 2). PSA suggested that the probabilities of ICM strategy being cost-effective were 53.4% and 78.7%, at thresholds of $30 000 (highly cost-effective) and $50 000 per QALY (cost-effective), respectively. CONCLUSIONS: Long-term continuous monitoring with an ICM is a cost-effective intervention to prevent recurrent stroke in patients following CS in the Australian context.

9.
J Med Econ ; 24(1): 1070-1082, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34415229

RESUMO

BACKGROUND: Despite treatment guidelines recommending the use of oral anticoagulants (OACs) for patients with non-valvular atrial fibrillation (NVAF) and moderate to high risk of stroke (CHA2DS2-VASc score ≥1), many patients remain untreated. A study conducted among Medicare beneficiaries with AF and a CHA2DS2-VASc score of ≥2 found that 51% of patients were not prescribed an OAC despite being eligible for treatment. When left untreated, NVAF poses an enormous burden to society, as stroke events are estimated to cost the US healthcare system about $34 billion each year in both direct medical costs and indirect productivity losses. This research explored the short-term clinical implications and budget impact (BI) of increasing OAC use among Medicare beneficiaries with NVAF. METHODS: A decision-analytic model was developed from the payer and societal perspectives to estimate the impact of increasing treatment rates among Medicare-eligible NVAF patients with a moderate-to-high risk of stroke over 1 year. Results of the model compared (1) a base case scenario using literature-derived rates of OAC use, and (2) a hypothetical scenario assuming an absolute 5% increase in overall OAC use. Clinical outcomes included the incremental annual number of ischemic stroke, hemorrhagic stroke, and gastrointestinal bleeding events, and stroke-related deaths. Economic outcomes included incremental annual and per-member per-month (PMPM) direct medical costs for the payer perspective and the incremental sum of annual direct medical and indirect costs from productivity loss and caregiver burden for the societal perspective. RESULTS: In total, 1.95 million Medicare patients with NVAF were estimated to be treated with OACs in the base case (3.8% of beneficiaries). In the hypothetical scenario analysis, nearly 200,000 more patients were treated resulting in 3,705 fewer ischemic strokes, 14 fewer gastrointestinal bleeds, 141 more hemorrhagic strokes, and 175 fewer deaths. The total incremental BI was $399.16 million ($0.65 PMPM) from the payer perspective and $377.10 million from the societal perspective due to indirect cost savings ($22.06 million). CONCLUSION: Our findings suggest that increased overall OAC use has a positive clinical benefit on the annual number of ischemic stroke events and deaths avoided in the Medicare population, while maintaining a modest increase in the overall BI to the Medicare system.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Administração Oral , Idoso , Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Redução de Custos , Humanos , Medicare , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Estados Unidos/epidemiologia
10.
Lab Chip ; 9(24): 3526-34, 2009 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20024032

RESUMO

A novel approach was developed for mapping the location of target DNA in tissue sections. The method combines a high-density, multi-well plate with an innovative single-tube procedure to directly extract, amplify, and detect the DNA in parallel while maintaining the two-dimensional (2D) architecture of the tissue. A 2D map of the gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was created from a tissue section and shown to correlate with the spatial area of the sample. It is anticipated that this approach may be easily adapted to assess the status of multiple genes within tissue sections, yielding a molecular map that directly correlates with the histology of the sample. This will provide investigators with a new tool to interrogate the molecular heterogeneity of tissue specimens.


Assuntos
DNA/análise , Técnicas de Preparação Histocitológica , Reação em Cadeia da Polimerase/métodos , Mama/patologia , DNA/genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Dispositivos Lab-On-A-Chip , Masculino , Miniaturização , Especificidade de Órgãos , Reação em Cadeia da Polimerase/instrumentação , Próstata/patologia , Reprodutibilidade dos Testes
11.
Clin Cancer Res ; 14(12): 3699-705, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18559586

RESUMO

The past several years have seen unprecedented advances in the application of various therapeutic strategies for the treatment of patients with renal cancer. The availability of active immunotherapy, antiangiogenic therapy, and targeted therapy for this disease has brought front and center issues related to choosing the appropriate treatment for particular patient populations. It is increasingly evident that the most promising treatment selection strategies will incorporate identifying specific features of the tumor itself. To facilitate this move toward personalized medicine, it is critically important to establish some standard principles for renal cancer tissue collection, preparation, and analysis for translational research studies. In this article, we identify and discuss some critical issues related to tissue-based kidney cancer research. We focus on five major areas as follows: (a) surgical and image-guided techniques for tissue collection; (b) quality control of specimen collection, processing, storage, and review; (c) issues related to analysis of paraffin embedded tissues; (d) genomic studies; and (e) assessment of reproducibility of assays across institutions. In addition, some practical implementation strategies are proposed. Although many of the topics discussed are specific for renal cancer, several are also relevant to tissue based biomarker investigations in a broad array of malignancies.


Assuntos
Carcinoma de Células Renais/patologia , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/tendências , Neoplasias Renais/patologia , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/tendências , Algoritmos , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/cirurgia , Genômica/métodos , Humanos , Neoplasias Renais/genética , Neoplasias Renais/cirurgia , Modelos Biológicos , Inclusão em Parafina/métodos , Controle de Qualidade , Projetos de Pesquisa , Cirurgia Assistida por Computador/métodos , Bancos de Tecidos
12.
Cancer Prev Res (Phila) ; 12(7): 471-480, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31239263

RESUMO

We address the dilemma faced by oncologists in administering preventative measures to "at risk" patients diagnosed with atypical and nonatypical hyperplasias due to lack of any molecular means of risk stratification and identifying high-risk subjects. Our study purpose is to investigate a four marker risk signature, MMP-1, CEACAM6, HYAL1, and HEC1, using 440 hyperplastic tissues for identifying high-risk subjects who will benefit from preventative therapies. We assayed the markers by IHC and combined their expression levels to obtain a composite value from 0-10, which we called a "Cancer Risk Score." We demonstrate that the four marker-based risk scores predict subsequent cancer development with an accuracy of 91% and 86% for atypical and nonatypical subjects, respectively. We have established a correlation between risk scores and cancer rates by stratifying the samples into low risk (score ≤ 0.5); intermediate risk (score ≤ 5.4), and high risk (score >5.4) groups using Kaplan-Meier survival analysis. We have evaluated cancer rates at 5, 10, and 15 years. Our results show that the average cancer rates in the first 5 years among low- and intermediate-risk groups were 2% and 15%, respectively. Among high-risk group, the average cancer rates at 5 years were 73% and 34% for atypical and nonatypical subjects, respectively. The molecular risk stratification described here assesses a patient's tumor biology-based risk level as low, intermediate, or high and for making informed treatment decisions. The outcomes of our study in conjunction with the available prophylactic measures could prevent approximately 20%-25% of sporadic breast cancers.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Hiperplasia/patologia , Medição de Risco/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/epidemiologia , Carcinoma Lobular/metabolismo , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Hiperplasia/epidemiologia , Hiperplasia/metabolismo , Incidência , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Estados Unidos/epidemiologia
13.
Mol Biochem Parasitol ; 157(1): 32-43, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17996962

RESUMO

Protein geranylgeranyltransferase type I (PGGT-I) and protein farnesyltransferase (PFT) occur in many eukaryotic cells. Both consist of two subunits, the common alpha subunit and a distinct beta subunit. In the gene database of protozoa Trypanosoma cruzi, the causative agent of Chagas' disease, a putative protein that consists of 401 amino acids with approximately 20% amino acid sequence identity to the PGGT-I beta of other species was identified, cloned, and characterized. Multiple sequence alignments show that the T. cruzi ortholog contains all three of the zinc-binding residues and several residues uniquely conserved in the beta subunit of PGGT-I. Co-expression of this protein and the alpha subunit of T. cruzi PFT in Sf9 insect cells yielded a dimeric protein that forms a tight complex selectively with [(3)H]geranylgeranyl pyrophosphate, indicating a key characteristic of a functional PGGT-I. Recombinant T. cruzi PGGT-I ortholog showed geranylgeranyltransferase activity with distinct specificity toward the C-terminal CaaX motif of protein substrates compared to that of the mammalian PGGT-I and T. cruzi PFT. Most of the CaaX-containing proteins with X=Leu are good substrates of T. cruzi PGGT-I, and those with X=Met are substrates for both T. cruzi PFT and PGGT-I, whereas unlike mammalian PGGT-I, those with X=Phe are poor substrates for T. cruzi PGGT-I. Several candidates for T. cruzi PGGT-I or PFT substrates containing the C-terminal CaaX motif are found in the T. cruzi gene database. Among five C-terminal peptides of those tested, a peptide of a Ras-like protein ending with CVLL was selectively geranylgeranylated by T. cruzi PGGT-I. Other peptides with CTQQ (Tcj2 DNAJ protein), CAVM (TcPRL-1 protein tyrosine phosphatase), CHFM (a small GTPase like protein), and CQLF (TcRho1 GTPase) were specific substrates for T. cruzi PFT but not for PGGT-I. The mRNA and protein of the T. cruzi PGGT-I beta ortholog were detected in three life-cycle stages of T. cruzi. Cytosol fractions from trypomastigotes (infectious mammalian stage) and epimastigotes (insect stage) were shown to contain levels of PGGT-I activity that are approximately 100-fold lower than PFT activity. The CaaX mimetics known as PGGT-I inhibitors show very low potency against T. cruzi PGGT-I compared to the mammalian enzyme, suggesting the potential to develop selective inhibitors against the parasite enzyme.


Assuntos
Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/enzimologia , Alquil e Aril Transferases/antagonistas & inibidores , Alquil e Aril Transferases/isolamento & purificação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Clonagem Molecular , Sequência Conservada , Citosol/química , DNA de Protozoário/química , DNA de Protozoário/genética , Inibidores Enzimáticos/farmacologia , Marcação por Isótopo , Dados de Sequência Molecular , Fosfatos de Poli-Isoprenil/metabolismo , Ligação Proteica , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/isolamento & purificação , Alinhamento de Sequência , Especificidade por Substrato , Trítio/metabolismo
14.
Methods Mol Biol ; 424: 433-48, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18369881

RESUMO

Procurement of pure populations of cells from heterogeneous histological sections can be accomplished utilizing tissue microdissection. At present, a variety of different manual and laser-based dissection tools are available and each method has particular strengths and weaknesses. The types of biomolecular analyses that can be performed on microdissected cells depend not only on the method of cell procurement, but also on the effects of upstream tissue handling and processing. Tissue preparation protocols include two major approaches; snap-freezing, or, fixation and embedding. Snap-freezing generally provides the best quality tissue for subsequent study, including proteomic analyses such as two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Tissue fixatives include either precipitating reagents or biomolecular cross-linkers. The fixed samples are then further processed and embedded in a wax medium. In general, the biomolecules recovered from fixed and embedded tissue specimens are lower in both quantity and quality than those from snap-frozen specimens, although they are useful for certain types of analyses. The protocols provided here for tissue handling and processing, preparation of tissue sections, and microdissection are derived from our experience at the Pathogenetics Unit of the National Cancer Institute.


Assuntos
Criopreservação/métodos , Microdissecção/instrumentação , Microdissecção/métodos , Fixação de Tecidos/métodos , Animais , Histocitoquímica/métodos , Humanos
15.
J Med Econ ; 21(8): 799-809, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29741126

RESUMO

AIMS: The goal of this study was to assess the cost-effectiveness of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) from an Australian payer perspective. METHODS: This study used a Markov model that employed a life-time time horizon, modeling patients from symptom onset of stroke until end of life. Clinical efficacy and safety data were taken from an individual patient level data (IPD) meta-analysis of clinical studies. The treatment effect of MT compared to usual care was measured by changes in modified Rankin Score (mRS). Post-treatment mRS scores were used to determine short- and long-term stroke care costs. Treatment costs were modeled, with health state utility values determined by literature review. All analyses were conducted using Microsoft Excel. RESULTS: In comparison to usual care, MT is associated with higher costs ($10,666 per patient) and additional quality-adjusted life years (QALYs) (0.8281 per patient), resulting in an incremental cost per QALY of $12,880. Sensitivity analyses demonstrated the reliability of the base case results across a range of assumptions. The higher cost associated with MT is, to an extent, offset by the cost savings resulting from lower stroke care costs due to improved patient outcomes. The life-time cost savings in terms of stroke care costs are estimated to be more than $8,000 per patient for patients who had received MT in combination with usual care. LIMITATIONS: Stroke care costs based on patient disability/functional level were not available and were derived. As a consequence, long-term care costs for patients with poorer outcomes may be under-estimated. Patient outcomes at 90 days were extrapolated to a lifetime horizon, but this approach was supported by long-term evidence on stroke survival. CONCLUSIONS: Mechanical thrombectomy is a cost-effective treatment option for AIS, with clinical benefits translating to short- and long-term cost benefits. This analysis supports rapid update of stroke care pathways to incorporate this therapy as a treatment option.


Assuntos
Acidente Vascular Cerebral/cirurgia , Trombectomia/economia , Trombectomia/métodos , Austrália , Análise Custo-Benefício , Feminino , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Cadeias de Markov , Modelos Econométricos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Reprodutibilidade dos Testes
16.
Plast Reconstr Surg Glob Open ; 6(12): e1921, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30656092

RESUMO

Periocular necrotizing fasciitis is a rare, but potentially blinding, or even fatal disease. The authors report a case of a 44-year-old man who presented with quiescent bilateral periocular and facial necrotizing fasciitis. The patient was treated with antibiotics and surgical debridement, followed by negative-pressure wound therapy (NPWT), until the wound bed was thought to be healthy enough to support bilateral upper eyelid full-thickness skin grafts. NPWT appeared to decrease local edema; speed reperfusion and granulation tissue formation; and served to stabilize the skin grafts against the wound bed, while not causing any ocular complications. NPWT can be a safe and effective adjunct treatment for periocular necrotizing fasciitis.

17.
J Mol Diagn ; 9(3): 297-304, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17591928

RESUMO

Layered peptide array is a new methodology for multiplex molecular measurements from two-dimensional life science platforms. The technology can be used in several different configurations depending on the needs of the investigator. Described here is an indirect layered peptide array (iLPA) that is capable of measuring proteins on a solid surface, such as target antigens on a tissue section. A prototype iLPA system was developed and subsequently examined for reproducibility and specificity and then compared with standard immunohistochemistry. Semiquantitative, multiplex proteomic analysis of histological sections was achieved with up to 20 membranes. The experimental variability was 18%. Overall, the data suggest that iLPA technology will be a relatively simple and inexpensive method for molecular measurements from tissue sections.


Assuntos
Imuno-Histoquímica/métodos , Fragmentos de Peptídeos/análise , Análise Serial de Proteínas/métodos , Neoplasias Encefálicas/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Neoplasias do Colo/metabolismo , Estudos de Viabilidade , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Linfoma/metabolismo , Masculino , Melanoma/metabolismo , Modelos Biológicos , Neurilemoma/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias da Próstata/metabolismo , Análise Serial de Tecidos/métodos
18.
Mol Biochem Parasitol ; 153(2): 115-24, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17397944

RESUMO

The C-terminal "CaaX"-motif-containing proteins usually undergo three sequential post-translational processing steps: (1) attachment of a prenyl group to the cysteine residue; (2) proteolytic removal of the last three amino acids "aaX"; (3) methyl esterification of the exposed alpha-carboxyl group of the prenyl-cysteine residue. The Trypanosoma brucei and Leishmania major Ras converting enzyme 1 (RCE1) orthologs of 302 and 285 amino acids-proteins, respectively, have only 13-20% sequence identity to those from other species but contain the critical residues for the activity found in other orthologs. The Trypanosoma brucei a-factor converting enzyme 1 (AFC1) ortholog consists of 427 amino acids with 29-33% sequence identity to those of other species and contains the consensus HExxH zinc-binding motif. The trypanosomatid RCE1 and AFC1 orthologs contain predicted transmembrane regions like other species. Membranes from Sf9 cells expressing the RCE1 ortholog of T. brucei or L. major showed proteolytic activity against farnesylated RAS-CVIM, whereas membranes containing T. brucei AFC1 ortholog were inactive. The results suggest that RCE1 is responsible for proteolytic removal of the C-terminal aaX from prenyl-CaaX proteins in these parasites. All the three enzymatic post-translational processes are thought to be required for proper cellular functioning of CaaX-proteins in eukaryotic cells. We carried out RNA interference experiments in Trypanosoma brucei of the enzymes involved in farnesyl protein post-translational modification to evaluate their importance in cell proliferation. Knockdown of T. brucei PFT beta subunit and RCE1 mRNAs resulted in >20-fold suppression of cell growth and dramatic morphologic changes. Knockdown of PPMT mRNA caused less dramatic effects on growth but induced noticeable changes in cell morphology.


Assuntos
Alquil e Aril Transferases/metabolismo , Leishmania major/enzimologia , Prenilação de Proteína , Processamento de Proteína Pós-Traducional , Proteínas de Protozoários/metabolismo , Interferência de RNA , Trypanosoma brucei brucei/enzimologia , Alquil e Aril Transferases/genética , Sequência de Aminoácidos , Animais , Células Cultivadas , Endopeptidases/química , Endopeptidases/genética , Endopeptidases/metabolismo , Humanos , Leishmania major/genética , Leishmania major/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Metaloendopeptidases/química , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Dados de Sequência Molecular , Proteínas Metiltransferases/química , Proteínas Metiltransferases/genética , Proteínas Metiltransferases/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Spodoptera , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo
19.
Ann N Y Acad Sci ; 1098: 451-3, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17435150

RESUMO

The layered peptide array (LPA) is a recently developed technique designed to measure antibody levels in a multiplex, high-throughput manner. LPAs can assess antibody presence either in fluid samples or from tissues while maintaining the two-dimensional orientation of the life science platform. In this manuscript, we evaluated and assessed the performance of the LPA platform, focusing on throughput capability, sensitivity, and specificity of the assay in several different systems.


Assuntos
Anticorpos/análise , Peptídeos/análise , Análise Serial de Proteínas , Anticorpos/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Peptídeos/sangue
20.
BJU Int ; 100(6): 1245-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17850370

RESUMO

OBJECTIVE: To assess the significance of viable tumour in the prostate of patients with metastatic androgen-independent prostate cancer (AIPC). PATIENTS AND METHODS: We evaluated the clinicopathological features, including follow-up, of 40 men with metastatic AIPC who had a transrectal biopsy of the prostate. RESULTS: Prostate biopsies (median three cores per biopsy) showed viable tumour in 19 of 40 patients (48%). Of the 18 patients who had received radiotherapy (RT), nine had negative on-study biopsy results. A previous history of RT was not associated with overall survival in patients with biopsy-positive tumours (P = 0.84). Also, there was no statistically significant association between positive or negative biopsy status and overall survival (OS) in these 40 patients (P = 0.39), with a similar median OS of 19.6 months for biopsy-negative and 19.8 months for biopsy-positive patients, respectively. CONCLUSIONS: Taking prostate biopsies at the time of documented metastatic AIPC yielded tumour in about half the patients. A previous history of RT was not associated with a negative prostate biopsy; the latter appears to have no influence on the prognosis.


Assuntos
Androgênios/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Próstata/patologia , Neoplasias da Próstata/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Biópsia por Agulha , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/terapia , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/terapia
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