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1.
J Econ Entomol ; 116(1): 160-167, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36383256

RESUMO

The corn earworm, Helicoverpa zea (Boddie), is a major pest of row crops in the Southern United States. Control of this insect is dependent on preventative insecticidal transgenic crops and synthetic insecticide applications when damaging populations are encountered in the field. Recently, the use of chemicals from the diamide class of insecticides, particularly chlorantraniliprole, has been used to control unacceptable populations. Due to the increased importance of this active ingredient for control of corn earworms, populations of this insect from the Mississippi Delta have been monitored for susceptibilities annually since 2016. Overall, 58 populations of H. zea were examined for their susceptibility to chlorantraniliprole through diet-incorporated bioassays from 2016 to 2021. Based on probit analysis, there was only a 4-fold difference between the highest and lowest LC50 estimates for all populations tested. Through weights of 2nd and 3rd instar larvae, there appears to be a substantial fitness cost associated with surviving caterpillars that fed on various concentrations of chlorantraniliprole in bioassays, which is not captured through the yes or no response of typical survival analysis. Overall, there was not a detectable trend of reduced susceptibility to chlorantraniliprole over the course of the six-year study.


Assuntos
Inseticidas , Lepidópteros , Mariposas , Estados Unidos , Animais , Inseticidas/farmacologia , Diamida , Zea mays , Larva , Resistência a Inseticidas , Controle Biológico de Vetores
2.
JAMA Oncol ; 9(2): 261-265, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580285

RESUMO

Importance: Molecular testing in non-small cell lung cancer (NSCLC) is commonly limited by inadequate tumor sample. Plasma cell-free DNA (cfDNA) genotyping as a complementary test is specific but only moderately sensitive. Genotyping of cfDNA in pleural and pericardial effusion (PE-cfDNA) can further optimize molecular diagnostic yield and reduce the need for repeated biopsies. Objective: To prospectively validate droplet digital polymerase chain reaction (ddPCR) for detection of sensitizing EGFR variants and acquired Thr790Met variant (T790M) from PE-cfDNA in patients with NSCLC. Design, Setting, and Participants: This prospective diagnostic validation study was conducted between September 6, 2016, and January 21, 2021 at 2 major Hong Kong cancer centers. Patients with advanced NSCLC with both wild-type and variant EGFR status and exudative PE who underwent thoracocentesis or pericardiocentesis were randomly enrolled. Patients were either EGFR-tyrosine kinase inhibitor (TKI) naive (cohort 1) or EGFR-TKI treated but osimertinib naive (cohort 2). Enrolled patients underwent pleural- or pericardial-fluid and blood sampling for ddPCR EGFR testing. EGFR status results with ddPCR testing of PE-cfDNA and blood were compared with EGFR status in matched tumor biopsy or PE cell block samples. Main Outcomes and Measures: Specificity, sensitivity, and concordance of PE-cfDNA for detection of sensitizing EGFR variants and acquired T790M variation. Results: Among 171 patients (54% female) enrolled, there were 104 in cohort 1 and 67 in cohort 2. In cohort 1, 37% (38/102) were EGFR-variant positive; PE-cfDNA showed 97% sensitivity (95% CI, 92%-100%), 97% specificity (95% CI, 93%-100%), and 97% concordance (ĸ = 0.94, P < .001) for the detection of sensitizing EGFR variants. It was more sensitive than plasma in detecting sensitizing EGFR variants (97% vs 74%, P < .001). In cohort 2, 38% (15 of 40) were positive for the EGFR T790M variant; PE-cfDNA showed 87% sensitivity (95% CI, 69%-100%), 60% specificity (95% CI, 41%-79%), and 70% concordance (ĸ = 0.42, P = .004) for acquired T790M. The EGFR T790M variant was detected in 51% of PE-cfDNA vs 25% of PE cell block samples. Conclusions and Relevance: In this diagnostic study, EGFR variants could be accurately detected from PE-cfDNA in patients with NSCLC. More EGFR T790M was detected in PE-cfDNA than in guideline-recommended PE cell block preparations. These results suggest that PE-cfDNA can complement plasma and tumor genotyping for detecting EGFR variants in patients with advanced NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ácidos Nucleicos Livres , Neoplasias Pulmonares , Derrame Pericárdico , Humanos , Feminino , Masculino , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Ácidos Nucleicos Livres/genética , Derrame Pericárdico/genética , Receptores ErbB/genética , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Mutação
3.
Adv Sci (Weinh) ; 7(10): 1903727, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32440486

RESUMO

Germline polymorphisms are linked with differential survival outcomes in cancers but are not well studied in nasopharyngeal carcinoma (NPC). Here, a two-phase association study is conducted to discover germline polymorphisms that are associated with the prognosis of NPC. The discovery phase includes two consecutive hospital cohorts of patients with NPC from Southern China. Exome-wide genotypes at 246 173 single nucleotide polymorphisms (SNPs) are determined, followed by survival analysis for each SNP under Cox proportional hazard regression model. Candidate SNP is replicated in another two independent cohorts from Southern China and Singapore. Meta-analysis of all samples (n = 5553) confirms that the presence of rs1131636-T, located in the 3'-UTR of RPA1, confers an inferior overall survival (HR = 1.33, 95% CI = 1.20-1.47, P = 6.31 × 10-8). Bioinformatics and biological assays show that rs1131636 has regulatory effects on upstream RPA1. Functional studies further demonstrate that RPA1 promotes the growth, invasion, migration, and radioresistance of NPC cells. Additionally, miR-1253 is identified as a suppressor for RPA1 expression, likely through regulation of its binding affinity to rs1131636 locus. Collectively, these findings provide a promising biomarker aiding in stratifying patients with poor survival, as well as a potential drug target for NPC.

4.
Am Soc Clin Oncol Educ Book ; 40: 1-11, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32191137

RESUMO

Epstein-Barr virus (EBV) associated nasopharyngeal carcinoma (NPC) is endemic in Southern China, and the prognosis of this cancer has improved in part due to advances in radiotherapy (RT) techniques, broadened therapeutic options, and more precise prognostic stratification of patients. RT is the primary curative treatment of NPC, and the incorporation of chemotherapy (induction, concurrent, adjuvant) to RT has contributed to improved survival in patients with locoregionally advanced NPC. Concurrent chemoradiotherapy (CCRT) in combination with adjuvant or induction chemotherapy is now the standard treatment of locoregionally advanced NPC, but the ideal CCRT therapeutic strategy for NPC remains controversial. Plasma EBV DNA is the archetypal tumor-derived DNA in NPC, and three generations of studies have gradually expanded its clinical applications. Recently, the advent of whole exome/genome sequencing of NPC and the promising clinical activity of immune checkpoint inhibitors have also spurred interest in the development of newer biomarkers. This review will focus on two clinical advances in NPC research that have made substantial impact on the contemporary management of NPC: (1) The integration of plasma EBV DNA in an expanding spectrum of clinical indications, and the development of promising immune-related biomarkers; (2) the current development of CCRT with special emphasis on the use of induction and adjuvant chemotherapy, as well as the potential applications of metronomic chemotherapy and immune checkpoint inhibitors in the treatment of locoregionally advanced NPC.


Assuntos
Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Biomarcadores Tumorais , Quimiorradioterapia , Feminino , Humanos , Masculino , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas
5.
Cancer Manag Res ; 11: 2719-2727, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040713

RESUMO

PURPOSE: Health-related quality of life (HRQoL) is a significant prognostic factor for overall survival in hepatocellular carcinoma (HCC) patients, and this is independent of stage and liver function. Inflammation plays a significant role in HCC development and progression. It was hypothesized that the inflammatory status of HCC patients may affect their HRQoL. The relationship between HRQoL and inflammatory status was explored using indicators IL-8 level and modified inflammation-based index (mIBI, based on IL-8, C-reactive protein, and albumin). METHODS: From 2007-2011, HCC patients were enrolled prospectively. Baseline HRQoL assessment utilized the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-HCC18; clinical and laboratory data were collected at diagnosis. Two summary indices, C30 and HCC18 index-scores, were calculated. Correlation analyses were performed between HRQoL and inflammatory markers. RESULTS: In the 445 patients studied, significant correlations were found between IL-8 levels and EORTC QLQ-C30, QLQ-HCC18, C30, and HCC18 index-scores. The strongest correlated factors were those reflective of constitutional symptoms, namely QLQ-C30 "appetite loss" (with Pearson's correlation coefficient, r=0.322, P<0.0001); QLQ-C30 "fatigue" (r=0.311, P<0.0001); QLQ-C30 "role functioning" (r=-0.305, P<0.0001); QLQ-HCC18 "nutrition" (r=0.317, P<0.0001); and QLQ-HCC18 "fatigue" (r=0.306, P<0.0001). In addition, moderate but significant correlations were also observed with HCC18 index score (r=0.321, P<0.0001), and C30 index score (r=0.306, P<0.0001). HRQoL factors were also significantly correlated with mIBI. CONCLUSION: Baseline HRQoL using the conventional assessments of EORTC QLQ-C30 and QLQ-HCC18, as well as C30 and HCC18 index-scores, significantly correlated with inflammatory indicators (IL-8 level and mIBI) in HCC patients. Among the strongest correlations were those between IL-8 level and the two index-scores, as well as HRQoL aspects that represent constitutional symptoms. When paralleled with molecular findings, traditional HRQoL assessment in HCC has gained a new level of understanding: pattern recognition within an HRQoL instrument could potentially identify patients with more severe inflammatory state.

6.
J Econ Entomol ; 110(3): 1039-1051, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334359

RESUMO

Laboratory and field experiments were conducted to determine the effectiveness of microbial and chemical insecticides for supplemental control of bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), on non-Bt (DP1441RF) and Bt (DP1321B2RF) cottons. Neonate and 3rd instar larvae survival was evaluated on leaf tissue treated with microbial and chemical insecticides including a commercial formulation of Bacillus thuringiensis (Dipel), a Heliothis (Helicoverpa) nuclear polyhedrosis virus (NPV; Gemstar), λ-cyhalothrin (Karate Z), and chlorantraniliprole (Prevathon). Residual activity of insecticides was measured in a small plot field experiment. The performance of microbial insecticides, with the exception of a mid-rate of Dipel with neonate larvae, was comparable with that of chemical treatments on non-Bt cotton leaves with regard to 1st and 3rd instar bollworm mortality at 10 d and pupal eclosion at 20-d post treatment. Production-level field evaluations of supplemental bollworm control in non-Bt and Bt cottons with NPV, λ-cyhalothrin, and chlorantraniliprole were also conducted. During both years of the field study, all chemical and microbial treatments were successful in suppressing bollworm larval densities in non-Bt cotton below economic threshold levels. Overall, net returns above bollworm control, regardless of treatment, were negatively correlated with larval abundance and plant damage. In addition, there was no economic benefit for supplemental control of bollworms in Bt cotton at the larval densities observed during this study. These data provide benchmark comparisons for insect resistance management with microbial and chemical insecticides in Bt and non-Bt cottons and strategic optimization of the need to spray non-Bt and Bt cotton in IRM programs.


Assuntos
Agentes de Controle Biológico , Controle de Insetos , Inseticidas , Mariposas , Controle Biológico de Vetores , Animais , Bacillus thuringiensis/fisiologia , Gossypium/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Nitrilas , Nucleopoliedrovírus/fisiologia , Pupa/crescimento & desenvolvimento , Piretrinas , ortoaminobenzoatos
7.
Liver Int ; 37(2): 280-289, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27501075

RESUMO

BACKGROUNDS & AIMS: A number of circulating inflammatory factors are implicated in the pathogenesis and prognostication of hepatocellular carcinoma (HCC). We aim to evaluate the prognostication of multiple serum inflammatory factors simultaneously and develop an objective inflammatory score for HCC. METHODS: A prospective cohort of 555 patients with HCC with paired serum samples was accrued from 2009 to 2012. The blood levels of conventional inflammatory markers, namely C-reactive protein (CRP), albumin, neutrophils, lymphocytes and platelet, were determined, and 41 other exploratory markers were measured by a multiplex assay. The prognostication and interaction of markers were determined by univariate and multivarite analyses. RESULTS: The cohort was randomly divided into training cohort (n=139) and validation cohort (n=416). There were no differences in baseline characteristics between the two cohorts. In the training cohort, independent prognostic factors for overall survival included CRP (hazard ratio [HR] 1.107; P=.003), albumin (HR 0.953; P=.032) and interleukin-8 (HR=5.816; P<.001). We have modified the existing inflammation-based index (IBI) by adding serum interleukin-8 level. The modified IBI could stratify patients into four groups with distinct overall survival (P<.001). The results were also validated in the validation cohort. When compared with IBI and other conventional inflammatory markers, the modified IBI had better prognostic performance with higher c-index and homogeneity likelihood ratio chi-square. CONCLUSIONS: Among the conventional and exploratory circulating inflammatory markers, higher CRP, lower albumin and higher interleukin-8 were independent prognosticators. By combining these factors, a simple and accurate inflammatory index could be constructed.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Inflamação/sangue , Neoplasias Hepáticas/sangue , Idoso , Proteína C-Reativa/análise , Feminino , Hong Kong , Humanos , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neutrófilos/metabolismo , Prognóstico , Estudos Prospectivos , Albumina Sérica Humana/análise , Análise de Sobrevida
8.
J Econ Entomol ; 109(6): 2517-2524, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27651293

RESUMO

While transgenic plants targeting lepidopteran and coleopteran insects have been available for almost 20 yr, there are no transgenic crops that target hemipteran insects such as tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), though at least one company lists potential products in advanced stages of development. A resistance management model for the U.S. Mid-South was developed to aid in resistance risk assessments for transgenic crops targeting L. lineolaris, and validated against the prior case of pyrethroid resistance in this insect. The model predicted that resistance to a pyrethroid would evolve in 17.6-21.0 yr (depending on the initial resistance allele frequency), which was close to the 15-20 years observed in the field. Due to uncertainty in female fecundity, we varied fecundity from 3 eggs/female/day to 12 eggs/female/day. Sprays were applied based on action thresholds, and increasing fecundity therefore increased the number of sprays applied per year and decreased durability. We also varied the action threshold in cotton (Gossypium hirsutum L.) fields (the population levels at which sprays were applied) from 17,600/ha to as low as 1,100/ha. Lowering the threshold increased the number of sprays applied, but also increased durability of the pesticide. Removing the noncotton host refuge present at the same time as cotton changed the relationship so that increasing the action threshold increased durability. The impact of insect resistance management on action threshold cost estimates will vary depending on the landscape, and cannot be assumed to always move the economic injury level in the same direction.


Assuntos
Gossypium/genética , Hemípteros , Controle de Insetos , Resistência a Inseticidas , Plantas Geneticamente Modificadas/genética , Animais , Fertilidade/efeitos dos fármacos , Modelos Teóricos , Dinâmica Populacional , Sudeste dos Estados Unidos
10.
Cancer Treat Rev ; 45: 77-86, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26995632

RESUMO

Following the approval of sorafenib, a large number of molecular targeted agents have been tested clinically for advanced hepatocellular carcinoma (HCC), but all have failed to demonstrate significant efficacy in clinical trials. Multiple reasons for this phenomenon have been discussed in the literature, with one reason being the lack of patient selection on the basis of molecular profile in clinical trials. The concept of drug testing in selected populations has been recently suggested by retrospective analyses of HCC clinical trials in which a particular subgroup of patients, either enriched by clinical factors or by tissue biomarkers, derived more benefits from the novel drug. In addition, recent advances in genomic medicine have enhanced the understanding of genetic and epigenetic events occurring in HCC, raising the possibility of personalizing targeted agents in accordance with the genetic make-up of the tumors. The development of 'personalized' treatment for HCC is, however, hindered by the lack of fresh biopsy of advanced HCC, the low incidence of genetic driver mutations in HCC and the tumor heterogeneity. These limitations may be overcome by sequencing cell-free DNA in plasma, frequently known as liquid biopsy, and revolution in the concept of the design of clinical trials. In this review article, we aim to: (1) give a summary of the recent sequencing results of HCC and the related implications for drug development; (2) highlight potential individual targeted agents and existing research on biomarker selection in clinical trials; and (3) discuss future directions, including the potential of liquid biopsy and umbrella clinical trials, to enhance personalized drug testing for HCC.


Assuntos
Antineoplásicos , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular , Neoplasias Hepáticas , Medicina de Precisão/métodos , Antineoplásicos/classificação , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Descoberta de Drogas , Testes Genéticos/métodos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
11.
Environ Entomol ; 44(3): 898-906, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26313997

RESUMO

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), is a major pest of cotton (Gossypium hirsutum L.) in the state of Mississippi. Economic data indicate that L. lineolaris is a more serious pest of cotton in the Delta region of Mississippi than in the Hills region; however, little data exist comparing the two populations. Two experiments were undertaken to compare L. lineolaris from these two geographically distinct regions. In the first experiment, colonies of L. lineolaris from each region were reared in the laboratory under controlled conditions and measurements of development time, survivorship, fecundity, and hatch rate were compared. The geographic region of origin had no effect on any of the variables measured; however, the diet used for rearing had a significant effect on all variables except hatch rate. In the second experiment, part of the cox1 gene of the L. lineolaris mitochondrial genome was compared between the two populations to examine possible genetic differences between L. lineolaris from the two regions of Mississippi. Data revealed two cox1 clades in the Delta region and only one cox1 clade in the Hills region. Taken together, the data do not explain the reason for the differences in the severity of damage to cotton in the two regions.


Assuntos
Gossypium , Herbivoria , Heterópteros/fisiologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Fertilidade , Gossypium/crescimento & desenvolvimento , Heterópteros/enzimologia , Heterópteros/genética , Heterópteros/crescimento & desenvolvimento , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Longevidade , Masculino , Mississippi , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia
12.
Mucosal Immunol ; 7(4): 857-68, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24280938

RESUMO

Phagocytes not only coordinate acute inflammation and host defense at mucosal sites, but also contribute to tissue damage. Respiratory infection causes a globally significant disease burden and frequently progresses to acute respiratory distress syndrome, a devastating inflammatory condition characterized by neutrophil recruitment and accumulation of protein-rich edema fluid causing impaired lung function. We hypothesized that targeting the intracellular protein myeloid cell leukemia 1 (Mcl-1) by a cyclin-dependent kinase inhibitor (AT7519) or a flavone (wogonin) would accelerate neutrophil apoptosis and resolution of established inflammation, but without detriment to bacterial clearance. Mcl-1 loss induced human neutrophil apoptosis, but did not induce macrophage apoptosis nor impair phagocytosis of apoptotic neutrophils. Neutrophil-dominant inflammation was modelled in mice by either endotoxin or bacteria (Escherichia coli). Downregulating inflammatory cell Mcl-1 had anti-inflammatory, pro-resolution effects, shortening the resolution interval (Ri) from 19 to 7 h and improved organ dysfunction with enhanced alveolar-capillary barrier integrity. Conversely, attenuating drug-induced Mcl-1 downregulation inhibited neutrophil apoptosis and delayed resolution of endotoxin-mediated lung inflammation. Importantly, manipulating lung inflammatory cell Mcl-1 also accelerated resolution of bacterial infection (Ri; 50 to 16 h) concurrent with enhanced bacterial clearance. Therefore, manipulating inflammatory cell Mcl-1 accelerates inflammation resolution without detriment to host defense against bacteria, and represents a target for treating infection-associated inflammation.


Assuntos
Pulmão/imunologia , Pulmão/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Caspases/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Infiltração de Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Piperidinas/farmacologia , Pneumonia/genética , Pneumonia/imunologia , Pneumonia/metabolismo , Pneumonia/microbiologia , Pneumonia/patologia , Pirazóis/farmacologia
13.
Environ Entomol ; 41(6): 1302-10, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23321077

RESUMO

Tarnished plant bugs, Lygus lineolaris (Palisot de Beauvois), overwinter as diapausing adults in North America. Overwintering adults were collected near Stoneville, MS from blooming henbit, Lamium amplexicaule L., and from plant debris during December and January and dissected to determine their reproductive status. Averaged over four winters, male and female tarnished plant bugs collected from henbit terminated diapause at a significantly higher rate than males and females from plant debris during each week of December and the first week of January. Both sexes in each habitat were nearly all reproductive by the end of January. Adults overwintering in plant debris terminated diapause during January in the absence of a food stimulus in all 5 yr studied. This emergence was thought to be controlled by an internal clock. Laboratory and field studies showed that emergence from diapause could be influenced by food, sex, and temperature. Adults overwintering on a suitable food source, blooming henbit, terminated diapause during December in the 4 yr studied, and males terminated diapause more rapidly than females. Food quality was important in emergence from diapause, and females on blooming henbit terminated diapause at a significantly higher rate than females on nonblooming mustard, Brassica juncea (L.) Cosson. Laboratory tests showed that diapausing adults reared in the laboratory and held at a diapause-maintaining photoperiod of 10:14 (L:D) h could be terminated from diapause by using food and temperature stimuli. The lower thermal threshold for development to reproductive adults was found to be near 10°C. The ability of diapausing adults to respond to food and temperature stimuli in December can enable tarnished plant bugs to take advantage of warm winters and winter hosts to produce a new generation earlier.


Assuntos
Heterópteros/fisiologia , Estágios do Ciclo de Vida/fisiologia , Temperatura , Animais , Brassica/crescimento & desenvolvimento , Brassica/fisiologia , Comportamento Alimentar , Feminino , Heterópteros/crescimento & desenvolvimento , Lamiaceae/crescimento & desenvolvimento , Lamiaceae/fisiologia , Masculino , Modelos Biológicos , Mostardeira/crescimento & desenvolvimento , Mostardeira/fisiologia , Estações do Ano , Fatores Sexuais
14.
Crit Care Med ; 37(8): 2441-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19531943

RESUMO

OBJECTIVE: To evaluate the usefulness of the Gram-specific probe-based quantitative polymerase chain reaction test for rapid detection and differentiation of Gram-negative and Gram-positive bacterial bloodstream infection in preterm infants. DESIGN: Cross-sectional study. SETTING: University-affiliated Level III neonatal intensive care unit. PATIENTS: Preterm infants with clinical features suggestive of late-onset infection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In addition to the full sepsis screen, 0.5 mL of EDTA blood was collected aseptically for Gram-specific quantitative polymerase chain reaction evaluation. The results were analyzed with respect to outcomes of bacterial culture in blood and other body fluids, including peritoneal and cerebrospinal fluids. The diagnostic utilities of the quantitative polymerase chain reaction were determined. A total of 218 suspected infection episodes were investigated, of which 42 episodes were culture positive and 176 were culture negative. For Gram-negative infection, the quantitative polymerase chain reaction test correctly identified 19 of 22 episodes, and the sensitivity and specificity were 86.4% and 99.0%, respectively. For Gram-positive infection, the test correctly identified 14/19 episodes, and the sensitivity and specificity were 73.7% and 98.5%. The remaining one episode was Candida albicans septicemia. None of the episodes with positive quantitative polymerase chain reaction test were classified into the wrong Gram stain category. More importantly, despite negative blood culture in five infants suffering from intra-abdominal sepsis (peritonitis [n = 4] and hepatosplenic abscess [n = 1]), the quantitative polymerase chain reaction test could detect the Gram-specific category of causative organisms in blood. CONCLUSIONS: The Gram-specific quantitative polymerase chain reaction test is reliable and highly specific for rapid identification and differentiation of Gram-negative and Gram-positive bloodstream and intra-abdominal infections. The result could be made available within 5 hrs after the specimen reaches the laboratory. A positive test is able to "rule in" bacterial bloodstream infection before blood culture results become available, and serves as a guide to predict the virulence of the causative organism according to its Gram-specific category so that critical patients can be targeted for intensive treatment.


Assuntos
Bacteriemia/diagnóstico , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Positivas/diagnóstico , Recém-Nascido Prematuro , Reação em Cadeia da Polimerase/métodos , Bacteriemia/microbiologia , Estudos Transversais , Diagnóstico Diferencial , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
15.
Clin Chim Acta ; 398(1-2): 113-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18801348

RESUMO

BACKGROUND: We investigated the value of plasma deoxyribonucleic acid concentrations in patients presenting with acute abdominal pain to predict need for intensive care or mortality. METHODS: Plasma deoxyribonucleic acid taken from patients with acute abdominal pain was analyzed for the beta-globin gene using the quantitative polymerase chain reaction. The primary outcome measure was the combined 28-day mortality or admission to the intensive care unit. RESULTS: Of 287 consecutive patients with acute abdominal pain recruited, 12 patients were admitted to the intensive care unit and/or died. Median plasma DNA concentrations were higher in patients with cancer and major organ inflammation. Mean plasma DNA concentrations were three-fold higher in patients with systemic inflammatory response syndrome, five-fold higher in patients who died within 28 days, and eight-fold higher in patients admitted to the intensive care unit. The area under the receiver operator curve for plasma DNA concentrations and intensive care unit admission/mortality was 0.804. At a cut-off of 1100 GE/ml, the sensitivity was 67% (95%CI 35-90) and specificity was 89% (95%CI 84-92). At a cut-off of 175 GE/ml, the sensitivity was 100% (95%CI 73-100) and specificity was 30% (95%CI 25-36). Plasma DNA concentration predicted need for intensive care unit admission or death (adjusted odds ratio 1.4; P<0.0001). CONCLUSIONS: Plasma DNA may have a role in patients with acute abdominal pain as a marker for inflammation and cancer, and a predictor of intensive care unit admission/mortality.


Assuntos
Dor Abdominal/genética , Dor Abdominal/mortalidade , Cuidados Críticos/estatística & dados numéricos , DNA/sangue , DNA/genética , Doença Aguda , Adulto , Idoso , Feminino , Seguimentos , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Plasma/química , Valor Preditivo dos Testes , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Resultado do Tratamento , Globinas beta/genética
16.
Ann Clin Biochem ; 40(Pt 2): 122-30, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12662399

RESUMO

There has recently been an upsurge of interest in the analysis of circulating nucleic acids (DNA and/or RNA) in blood plasma or serum as a clinical diagnostic tool. Occasional earlier reports suggested the existence of circulating nucleic acids, but the potential clinical implication was not realized until 1996, when DNA with tumour-specific characteristics was demonstrated in the plasma/serum of cancer patients. This finding opened up possibilities for non-invasive cancer diagnosis. Potential applications have been reported in cancer diagnosis, prenatal diagnosis, transplantation and traumatology. Some of the findings are on the verge of being translated into clinical use. DNA is also now being sought in other body fluids such as urine.


Assuntos
Ácidos Nucleicos/sangue , Ácidos Nucleicos/urina , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Feminino , Humanos , Neoplasias/diagnóstico , Gravidez , Diagnóstico Pré-Natal/métodos
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