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1.
J Clin Microbiol ; 58(11)2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32817233

RESUMO

We prospectively compared health care worker-collected nasopharyngeal swabs (NPS) to self-collected anterior nasal swabs (ANS) and straight saliva for the diagnosis of coronavirus disease 2019 (COVID-19) in 354 patients. The percent positive agreement between NPS and ANS or saliva was 86.3% (95% confidence interval [CI], 76.7 to 92.9%) and 93.8% (95% CI, 86.0 to 97.9%), respectively. The percent negative agreement was 99.6% (95% CI, 98.0 to 100.0%) for NPS versus ANS and 97.8% (95% CI, 95.3 to 99.2%) for NPS versus saliva. More cases were detected by the use of NPS (n = 80) and saliva (n = 81) than by the use of ANS (n = 70), but no single specimen type detected all severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Técnicas de Diagnóstico Molecular , Pneumonia Viral/diagnóstico , Manejo de Espécimes/métodos , Adolescente , Adulto , Idoso , Betacoronavirus/genética , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Nariz/virologia , Pandemias , SARS-CoV-2 , Saliva/virologia , Autocuidado , Adulto Jovem
2.
J Clin Microbiol ; 54(3): 785-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26719436

RESUMO

We evaluated a multiplexed PCR panel for the detection of 16 bacterial, viral, and fungal pathogens in cerebrospinal fluid. Panel results were compared to routine testing, and discrepancies were resolved by additional nucleic acid amplification tests or sequencing. Overall, the positive and negative agreements across methods were 92.9% and 91.9%, respectively.


Assuntos
Automação , Infecções do Sistema Nervoso Central/diagnóstico , Infecções do Sistema Nervoso Central/etiologia , Reação em Cadeia da Polimerase Multiplex , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Antimicrob Agents Chemother ; 59(11): 6725-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282428

RESUMO

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Anidulafungina , Candida/genética , Caspofungina , Micafungina , Testes de Sensibilidade Microbiana , Mutação/genética
5.
Transpl Infect Dis ; 16(3): 421-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24797543

RESUMO

BACKGROUND: Levofloxacin is routinely used for the prevention of invasive bacterial infections during autologous peripheral blood stem cell transplantation (APBSCT). However, increasing rates of bacterial sepsis were noted at our institution among multiple myeloma (MM) patients undergoing outpatient APBSCT with melphalan-based chemotherapy and levofloxacin prophylaxis. We assessed the impact of a change in antibacterial prophylaxis from oral levofloxacin (Period 1) to sequential oral levofloxacin followed by ertapenem (Period 2). METHODS: Electronic medical records were reviewed to identify MM patients who underwent APBSCT in the outpatient clinic between October 2007 and April 2012. RESULTS: Over a 4.5-year period, 165 outpatient APBSCTs were eligible for the analysis. Fewer overall bacteremias occurred during Period 2 as compared with Period 1 (0.5 cases per 100 person-days vs. 2.4 cases per 100 person-days, P<0.001). In addition, fewer patients were hospitalized for neutropenic fever while receiving sequential prophylaxis (45.7% vs. 75.7% of outpatient APBSCT recipients during Periods 2 and 1, respectively; P<0.001). In Kaplan-Meier analysis, receipt of sequential prophylaxis (Period 2) was significantly associated with overall bacteremia-free survival within 30 days after the APBSCT (P<0.001). No significant differences were seen in the number of patients developing Clostridium difficile infection or ertapenem-resistant gram-negative bacteremia between study periods. CONCLUSION: In conclusion, sequential prophylaxis may effectively prevent episodes of bacteremia and hospitalizations in neutropenic MM outpatient APBSCT recipients. Prospective studies that involve larger numbers of MM patients with extended periods of follow-up are ultimately required to define the safety and efficacy of sequential antibacterial prophylaxis.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Levofloxacino/uso terapêutico , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , beta-Lactamas/uso terapêutico , Idoso , Antibacterianos/administração & dosagem , Antineoplásicos , Ertapenem , Feminino , Hospitalização , Humanos , Levofloxacino/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Retrospectivos , beta-Lactamas/administração & dosagem
6.
New Dir Youth Dev ; 2014(143): 103-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25530243

RESUMO

Little is known about how the adoption of evidence-based physical activity (PA) curricula by out-of-school time (OST) programs affects children's physical fitness, and there are no clear guidelines of what constitutes reasonable gains given the types of PA instruction currently offered in these programs. Using a three-wave, quasi-experimental, naturalistic observation design, this study evaluated the implementation of an evidence-based PA instruction curriculum (Sports, Play, and Active Recreation for Kids [SPARK]) and examined whether the potential health benefits of evidence-based PA instruction can be replicated in this context when compared to OST programs that do not use evidence-based PA curricula. Quality of PA instruction and SPARK implementation fidelity were also assessed. Results indicated that children in the non-evidence-based/standard PA instruction programs engaged in higher levels of moderate-to-vigorous PA (MVPA) and showed greater improvements in fitness levels over time. The findings from this chapter suggest that while it is generally accepted that evidence-based approaches yield higher levels of PA when implemented by researchers under controlled conditions, findings are inconsistent when evidence-based PA instruction is implemented in the field, under presumably less controlled conditions. It appears that when it comes to PA instruction in afterschool, either less structured activities or well-implemented evidence-based practices could be the key to promoting higher PA levels and greater health and fitness for school-aged children.


Assuntos
Currículo , Prática Clínica Baseada em Evidências/métodos , Exercício Físico , Promoção da Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde , Aptidão Física , Adolescente , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas
7.
Clin Genet ; 81(5): 403-12, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22097934

RESUMO

The evidence-based review (EBR) process has been widely used to develop standards for medical decision-making and to explore complex clinical questions. This approach can be applied to genetic tests, such as chromosomal microarrays, in order to assist in the clinical interpretation of certain copy number variants (CNVs), particularly those that are rare, and guide array design for optimal clinical utility. To address these issues, the International Standards for Cytogenomic Arrays Consortium has established an EBR Work Group charged with building a framework to systematically assess the potential clinical relevance of CNVs throughout the genome. This group has developed a rating system enumerating the evidence supporting or refuting dosage sensitivity for individual genes and regions that considers the following criteria: number of causative mutations reported; patterns of inheritance; consistency of phenotype; evidence from large-scale case-control studies; mutational mechanisms; data from public genome variation databases; and expert consensus opinion. The system is designed to be dynamic in nature, with regions being reevaluated periodically to incorporate emerging evidence. The evidence collected will be displayed within a publically available database, and can be used in part to inform clinical laboratory CNV interpretations as well as to guide array design.


Assuntos
Variações do Número de Cópias de DNA/genética , Medicina Baseada em Evidências , Dosagem de Genes , Genoma Humano , Humanos , Fenótipo
8.
Int J Qual Health Care ; 23(4): 445-55, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21672923

RESUMO

OBJECTIVE: To assess the quality of medical treatment by disaggregating quality into components that distinguish between insufficient and unnecessary care. DESIGN: Randomly selected doctors were asked how they would treat a sick child. Their responses were disaggregated into how much of an evidence-based essential treatment plan was completed and the number of additional non-essential treatments that were given. Key variables included the expected cost, the health consequences of insufficient and unnecessary care and comparisons between public and private physicians. Responses to 160 clinical performance vignettes (CPVs) were analysed. SETTING: Philippines. PARTICIPANTS: One hundred and forty-three public and private physicians in the Philippines, collected in November 2003-December 2004 and September 2006-June 2007. INTERVENTIONS: CPVs administered to physicians. MAIN OUTCOME MEASURES: Process quality measures (accounting for the possibility of both over-treatment and under-treatment). RESULTS: Based on CPVs, doctors gave both insufficient and unnecessary treatment to under-five children in 69% of cases. Doctors who provided the least sufficient care were also the most likely to give costly or harmful unnecessary care. Insufficient care typically had potentially worse health consequences for the patient than unnecessary care, though unnecessary care remains a concern because of overuse of antibiotics (47%) and unnecessary hospitalization (34%). CONCLUSIONS: Quality of care is complex, but over- and under-treatment coexist and, in our analysis physicians that were more likely to under-treat a sick child were also those more likely to over-treat.


Assuntos
Pesquisa sobre Serviços de Saúde/métodos , Padrões de Prática Médica/normas , Indicadores de Qualidade em Assistência à Saúde , Adulto , Feminino , Humanos , Masculino , Filipinas , Padrões de Prática Médica/estatística & dados numéricos , Procedimentos Desnecessários/estatística & dados numéricos
9.
J Fish Dis ; 34(10): 783-91, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21916903

RESUMO

Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM), a common pathogen affecting aquaculture facilities and implicated in large losses of cultured fish. Fisheries scientists continue to gain a greater understanding of the disease and the pathogen by investigating methods of identification and pre- and post-infection treatment. In this study, a real-time PCR probe set for Y. ruckeri was developed to detect daily changes in the bacterial load during pathogen challenges. Two species of fish, Chinook salmon, Oncorhynchus tshawytscha, and steelhead trout, Oncorhynchus mykiss, were exposed to two strains of Y. ruckeri (Hag and SC) during bath challenges. A subset of fish was killed daily for 14 days, and the kidney tissue was biopsied to enumerate copies of pathogen DNA per gram of tissue. While Chinook exposed to either the Hag or SC strains exhibited similar pathogen loads, those exposed to the Hag strain displayed higher mortality (∼66%) than fish exposed to the SC strain (∼24% mortality). Steelhead exposed to the Hag strain exhibited a greater pathogen load and higher mortality (∼42%) than those exposed to the SC strain (<1% mortality). Steelhead challenged with either strain showed lower pathogen loads than Chinook. The study illustrates the efficacy of the probe set to enumerate Y. ruckeri bacterial growth in the kidneys of fish. Also, strains of Y. ruckeri display species-specific growth patterns that result in differential mortality and pathogen load.


Assuntos
Primers do DNA , Doenças dos Peixes/microbiologia , Oncorhynchus mykiss , Reação em Cadeia da Polimerase em Tempo Real , Salmão , Yersiniose/veterinária , Yersinia ruckeri , Animais , Carga Bacteriana , Doenças dos Peixes/mortalidade , RNA Ribossômico 16S/genética , Yersiniose/microbiologia , Yersiniose/mortalidade , Yersinia ruckeri/genética , Yersinia ruckeri/patogenicidade
10.
J Clin Densitom ; 13(3): 277-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20605499

RESUMO

Bone formation and resorption are influenced by inflammatory processes. We examined the relationships among inflammatory markers and bone mineral content (BMC) and density (BMD) and determined the contribution of inflammatory markers to 1-yr changes in BMC and BMD in healthy postmenopausal women. This analysis included 242 women at baseline from our parent Soy Isoflavones for Reducing Bone Loss project who were randomly assigned to 1 of 3 treatment groups: placebo, 80 mg/d soy isoflavones, or 120 mg/d soy isoflavones. BMD and BMC from the lumbar spine (LS), total proximal femur (hip), and whole body were measured by dual energy X-ray absorptiometry and the 4% distal tibia by peripheral quantitative computed tomography. Serum inflammatory markers (C-reactive protein, interleukin [IL]-1 beta, IL-6, tumor necrosis factor-alpha [TNF-alpha], and white blood cell count [WBC]) were measured at baseline, 6, and 12 mo. Because of attrition or missing values, data analysis at 12 mo includes only 235 women. Significant associations among IL-6, TNF-alpha, and WBC were observed with percent change in LS, hip, and whole body BMC and BMD. Multiple regression analysis indicated that in combination inflammatory markers accounted for 1.1-6.1% of the variance to the observed 12-mo changes in BMC and BMD. Our results suggest that modifying inflammatory markers, even in healthy postmenopausal women, may possibly reduce bone loss.


Assuntos
Densidade Óssea/fisiologia , Mediadores da Inflamação/fisiologia , Pós-Menopausa/fisiologia , Proteína C-Reativa/análise , Proteína C-Reativa/fisiologia , Feminino , Fêmur/fisiologia , Humanos , Mediadores da Inflamação/sangue , Interleucina-1beta/sangue , Interleucina-1beta/fisiologia , Interleucina-6/sangue , Interleucina-6/fisiologia , Contagem de Leucócitos , Vértebras Lombares/fisiologia , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/fisiologia
11.
Mol Autism ; 11(1): 12, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024554

RESUMO

BACKGROUND: Williams syndrome (WS) and autism spectrum disorder (ASD) are neurodevelopmental disorders that demonstrate overlapping genetic associations, dichotomous sociobehavioral phenotypes, and dichotomous pathological differences in neuronal distribution in key social brain areas, including the prefrontal cortex and the amygdala. The serotonergic system is critical to many processes underlying neurodevelopment and is additionally an important neuromodulator associated with behavioral variation. The amygdala is heavily innervated by serotonergic projections, suggesting that the serotonergic system is a significant mediator of neuronal activity. Disruptions to the serotonergic system, and atypical structure and function of the amygdala, are implicated in both WS and ASD. METHODS: We quantified the serotonergic axon density in the four major subdivisions of the amygdala in the postmortem brains of individuals diagnosed with ASD and WS and neurotypical (NT) brains. RESULTS: We found opposing directions of change in serotonergic innervation in the two disorders, with ASD displaying an increase in serotonergic axons compared to NT and WS displaying a decrease. Significant differences (p < 0.05) were observed between WS and ASD data sets across multiple amygdala nuclei. LIMITATIONS: This study is limited by the availability of human postmortem tissue. Small sample size is an unavoidable limitation of most postmortem human brain research and particularly postmortem research in rare disorders. CONCLUSIONS: Differential alterations to serotonergic innervation of the amygdala may contribute to differences in sociobehavioral phenotype in WS and ASD. These findings will inform future work identifying targets for future therapeutics in these and other disorders characterized by atypical social behavior.


Assuntos
Tonsila do Cerebelo/patologia , Transtorno do Espectro Autista/patologia , Axônios/patologia , Serotonina , Síndrome de Williams/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Dev Cell ; 1(4): 567-78, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11703946

RESUMO

We identified Drosophila Smurf (DSmurf) as a negative regulator of signaling by the BMP2/4 ortholog DPP during embryonic dorsal-ventral patterning. DSmurf encodes a HECT domain ubiquitin-protein ligase, homologous to vertebrate Smurf1 and Smurf2, that binds the Smad1/5 ortholog MAD and likely promotes its proteolysis. The essential function of DSmurf is restricted to its action on the DPP pathway. DSmurf has two distinct, possibly mechanistically separate, functions in controlling DPP signaling. Prior to gastrulation, DSmurf mutations cause a spatial increase in the DPP gradient, as evidenced by ventrolateral expansion in expression domains of target genes representing all known signaling thresholds. After gastrulation, DSmurf mutations cause a temporal delay in downregulation of earlier DPP signals, resulting in a lethal defect in hindgut organogenesis.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila , Drosophila/embriologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta , Ubiquitina/metabolismo , Animais , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 4 , Embrião não Mamífero/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Intestinos/embriologia , Ligases/genética , Dados de Sequência Molecular , Mutação/fisiologia , Homologia de Sequência de Aminoácidos , Ubiquitina-Proteína Ligases
13.
Science ; 202(4367): 513-5, 1978 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-17813489

RESUMO

Twenty years of atmospheric transmission data from Mauna Loa Observatory show secular decreases at irregular intervals. In addition, a regular annual variation is present during unperturbed as well as perturbed periods. These variations in transmission can be measured to a few tenths of a percent from the data record. Transient decreases in transmission are strongly correlated with explosive volcanic eruptions that inject effluent into the stratosphere. Recovery from these ejections takes as much as 8 years and the recovery curve is linear. Observations in 1977 at Mauna Loa show that, for the first time since the Mount Agung eruption in 1963, the atmospheric transmission of direct-incidence solar irradiation at Mauna Loa returned to values measured in 1958 to 1962.

15.
Mycorrhiza ; 19(4): 239-246, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19101737

RESUMO

Arbuscular mycorrhizal (AM) fungi facilitate inorganic N (NH(4)(+) or NO(3)(-)) uptake by plants, but their role in N mobilization from organic sources is unclear. We hypothesized that arbuscular mycorrhizae enhance the ability of a plant to use organic residues (ORs) as a source of N. This was tested under controlled glasshouse conditions by burying a patch of OR in soil separated by 20-microm nylon mesh so that only fungal hyphae can pass through it. The fate of the N contained in the OR patch, as influenced by Glomus claroideum, Glomus clarum, or Glomus intraradices over 24 weeks, was determined using (15)N as a tracer. AM fungal species enhanced N mineralization from OR to different levels. N recovery and translocation to Russian wild rye by hyphae reached 25% of mineralized N in G. clarum, which was most effective despite its smaller extraradical development in soil. Mobilization of N by G. clarum relieved plant N deficiency and enhanced plant growth. We show that AM hyphae modify soil functioning by linking plant growth to N mineralization from OR. AM species enhance N mineralization differentially leading to species-specific changes in the quality of the soil environment (soil C-to-N ratio) and structure of the soil microbial community.


Assuntos
Micorrizas/fisiologia , Nitrogênio/metabolismo , Poaceae/fisiologia , Microbiologia do Solo , Simbiose , Biomassa , Micorrizas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Poaceae/metabolismo
16.
Neuroimage Clin ; 22: 101800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991618

RESUMO

The threshold for amyloid positivity by visual assessment on PET has been validated by comparison to amyloid load measured histopathologically and biochemically at post mortem. As such, it is now feasible to use qualitative visual assessment of amyloid positivity as an in-vivo gold standard to determine those factors which can modify the quantitative threshold for amyloid positivity. We calculated quantitative amyloid load, measured as Standardized Uptake Value Ratios (SUVRs) using [18-F]florbetaben PET scans, for 159 Hispanic and non-Hispanic participants, who had been classified clinically as Cognitively Normal (CN), Mild Cognitive Impairment (MCI) or Dementia (DEM). PET scans were visually rated as amyloid positive (A+) or negative (A-), and these judgments were used as the gold standard with which to determine (using ROC analyses) the SUVR threshold for amyloid positivity considering factors such as age, ethnicity (Hispanic versus non-Hispanic), gender, cognitive status, and apolipoprotein E ε4 carrier status. Visually rated scans were A+ for 11% of CN, 39.0% of MCI and 70% of DEM participants. The optimal SUVR threshold for A+ among all participants was 1.42 (sensitivity = 94%; specificity = 92.5%), but this quantitative threshold was higher among E4 carriers (SUVR = 1.52) than non-carriers (SUVR = 1.31). While mean SUVRs did not differ between Hispanic and non-Hispanic participants;, a statistically significant interaction term indicated that the effect of E4 carrier status on amyloid load was greater among non-Hispanics than Hispanics. Visual assessment, as the gold standard for A+, facilitates determination of the effects of various factors on quantitative thresholds for amyloid positivity. A continuous relationship was found between amyloid load and global cognitive scores, suggesting that any calculated threshold for the whole group, or a subgroup, is artefactual and that the lowest calculated threshold may be optimal for the purposes of early diagnosis and intervention.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Apolipoproteína E4/genética , Disfunção Cognitiva , Demência , Hispânico ou Latino , Neuroimagem/normas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina , Disfunção Cognitiva/etnologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Demência/etnologia , Demência/genética , Demência/metabolismo , Demência/fisiopatologia , Feminino , Hispânico ou Latino/genética , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/normas , Sensibilidade e Especificidade , Fatores Sexuais , Estilbenos
17.
Cytotherapy ; 10(3): 289-302, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18418774

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection and its treatment causes significant morbidity following allogeneic stem cell transplantation (SCT) for malignancies. We studied the phenotype, function and growth kinetics of CMV pp65 antigen (Ag)-specific T cells expanded in a short-term culture for adoptive therapy. METHODS: Peripheral blood mononuclear cells (PBMC) from CMV-seropositive donors were cultured in various conditions with CMV pp65((495-503)) peptide to determine the most effective method for generating CMV-specific T cells. CMV-expanded cultures were tested for frequency, phenotype and functionality using peptide-MHC tetramer analysis, cytokine flow cytometry and cytolytic assays. A patient undergoing allogeneic SCT was administered CMV pp65-specific T cells generated from the donor based on these data, and recipient PBMC were analyzed following T-cell infusion. RESULTS: CMV pp65-specific T cells were consistently generated from CMV-seropositive donors at high frequencies (20-40% of CD8+ T cells), secreted interferon-gamma (IFN-gamma) in response to CMV peptide and had lytic activity against CMV peptide-expressing targets. Cultured CMV-specific T cells were infused into a SCT recipient without toxicity. DISCUSSION: Stimulating donor PBMC to generate functional, Ag-specific T cells for infusion into SCT recipients was accomplished consistently using readily available technology. We observed no toxicity in one patient receiving T cells and were able to monitor infused cells. These findings support further study of this approach as a prophylaxis against the risk of infection in patients receiving allogeneic transplantation from CMV-seropositive donors.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Imunoterapia Adotiva , Neoplasias/terapia , Transplante de Células-Tronco , Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Clonais , Citocinas/metabolismo , Citomegalovirus/efeitos dos fármacos , Epitopos , Transplante de Células-Tronco Hematopoéticas , Humanos , Cinética , Ativação Linfocitária/efeitos dos fármacos , Neoplasias/imunologia , Neoplasias/patologia , Peptídeos/farmacologia , Fenótipo , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Transplante Homólogo
18.
J Clin Invest ; 97(1): 172-9, 1996 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8550830

RESUMO

While it is known that nitric oxide (NO) is an important modulator of tone in the hypertensive pulmonary circulation, the roles of cyclic 3'-5'-guanosine monophosphate (cGMP) and cGMP-phosphodiesterase (PDE) are uncertain. We found that isolated lung perfusate levels of cGMP were over ninefold elevated in hypertensive vs. normotensive control rats. 98-100% of lung cGMP hydrolytic activity was cGMP-specific PDE5, with no significant decrease in PDE activity in hypertensive lungs, suggesting that the elevation in cGMP was due to accelerated production rather than reduced degradation. In pulmonary hypertensive rat lungs, in vitro, cGMP-PDE inhibition by E4021[1-(6-chloro-4-(3,4-methylbenzyl) amino-quinazolin-2-yl)piperdine-4-carboxylate], increased perfusate cGMP threefold, reduced hypoxic vasoconstriction by 58 +/- 2%, and reduced baseline pulmonary artery pressure by 37 +/- 5%. In conscious, pulmonary hypertensive rats, intravenous administration of E4021 reduced hypoxic vasoconstriction by 68 +/- 8%, pulmonary artery pressure by 12.6 +/- 3.7% and total pulmonary resistance by 13.1 +/- 6.4%, with no significant effect on cardiac output, systemic pressure, and resistance. Comparison of E4021 to inhaled nitric oxide demonstrated that cGMP-PDE inhibition was as selective and as effective as inhaled NO.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Hipertensão Pulmonar/fisiopatologia , Hipóxia/fisiopatologia , Pulmão/enzimologia , Circulação Pulmonar/fisiologia , Vasodilatação/fisiologia , 3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , GMP Cíclico/metabolismo , Diltiazem/farmacologia , Hemodinâmica , Técnicas In Vitro , Pulmão/irrigação sanguínea , Masculino , Óxido Nítrico/farmacologia , Perfusão , Inibidores de Fosfodiesterase/farmacologia , Piperidinas/farmacologia , Purinonas/farmacologia , Quinazolinas/farmacologia , Ratos , Ratos Sprague-Dawley
19.
J Clin Invest ; 100(10): 2611-21, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9366577

RESUMO

The diversity among cyclic nucleotide phosphodiesterases provides multiple mechanisms for regulation of cAMP and cGMP in the cardiovascular system. Here we report that a calmodulin-stimulated phosphodiesterase (PDE1C) is highly expressed in proliferating human arterial smooth muscle cells (SMCs) in primary culture, but not in the quiescent SMCs of intact human aorta. High levels of PDE1C were found in primary cultures of SMCs derived from explants of human newborn and adult aortas, and in SMCs cultured from severe atherosclerotic lesions. PDE1C was the major cAMP hydrolytic activity in these SMCs. PDE expression patterns in primary SMC cultures from monkey and rat aortas were different from those from human cells. In monkey, high expression of PDE1B was found, whereas PDE1C was not detected. In rat SMCs, PDE1A was the only detectable calmodulin-stimulated PDE. These findings suggest that many of the commonly used animal species may not provide good models for studying the roles of PDEs in proliferation of human SMCs. More importantly, the observation that PDE1C is induced only in proliferating SMCs suggests that it may be both an indicator of proliferation and a possible target for treatment of atherosclerosis or restenosis after angioplasty, conditions in which proliferation of arterial SMCs is negatively modulated by cyclic nucleotides.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/biossíntese , 3',5'-GMP Cíclico Fosfodiesterases/biossíntese , Aorta Torácica/enzimologia , Arteriosclerose/enzimologia , Músculo Liso Vascular/enzimologia , Diester Fosfórico Hidrolases , Adulto , Animais , Aorta Torácica/citologia , Aorta Torácica/patologia , Arteriosclerose/patologia , Células Cultivadas , Nucleotídeo Cíclico Fosfodiesterase do Tipo 1 , Indução Enzimática , Haplorrinos , Humanos , Lactente , Recém-Nascido , Músculo Liso Vascular/citologia , Músculo Liso Vascular/patologia , Fenótipo , Ratos , Proteínas Recombinantes/biossíntese , Morte Súbita do Lactente , Transcrição Gênica
20.
Mol Cell Biol ; 15(1): 45-51, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7799954

RESUMO

A two-marker selection system that allows the efficient isolation of diploid gene knockouts by two sequential rounds of targeted homologous recombination has been developed. A systematic evaluation of the biological parameters that govern the selection process showed that a successful strategy must match the expression level of the target gene, the efficacy of the marker, and the selection stringency. An enrichment ratio of 5,000- to 10,000-fold, which resulted in a 30% targeting efficiency of the c-myc gene in a fibroblast cell line, has been achieved. Such efficiency brings the difficulty of gene targeting effectively down to the level of simple transfections, since only 10 to 20 drug-resistant clones need to be screened to recover several homologous hits. The general utility of the targeting strategy is of interest to investigators studying gene function in a large variety of mammalian tissue culture systems.


Assuntos
Marcação de Genes/métodos , Recombinação Genética , Animais , Células Cultivadas , Eletroporação , Regulação da Expressão Gênica , Genes myc , Vetores Genéticos , Técnicas In Vitro , Ratos , Mapeamento por Restrição , Seleção Genética
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