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1.
Biomed Res Int ; 2022: 2545830, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281461

RESUMO

The global malaria morbidity and mortality witnessed an increase from 2019 to 2020 partly due to disruptions in control programs' activities imposed by the COVID-19 pandemic. Therefore, there is still a significant burden of malaria in Cameroon which needs attention from all fronts to attain elimination goals. It is normally expected that a typical forest ecology that has undergone urbanization and subjected to high rates of ecological instabilities should also have a shift from characteristic perennial malaria transmission and a shift in the type of malaria endemicity plaguing such distorted forest ecology. In this observational comparative study, we randomly enrolled participants from rural and urban settings of a forest zone during a low malaria transmission period, which coincided with the onset of COVID-19 pandemic. An optimized structured questionnaire was employed, to collect socio-demographic data and associated risk factors. The CareStart™ Malaria HRP2 antigen test was performed on participants from both settings to determine the prevalence of community asymptomatic malaria. Of 307 participants, 188 (61.0%) were from the rural, while 119 (38.8%) from the urban community. The overall prevalence of asymptomatic malaria (27.0%) detected Plasmodium falciparum antigen in 83 participants. The urban community's prevalence was 4.2% (5 positives) while the rural community's was 41.5% (78 positives). In simple logistic regression models, rural forest community and farm around the house were statistically significant predictors of testing positive (coefficient 2.8, 95% CI 1.8-3.7, p value<0.001) and (coefficient 3.1, 95% CI 1.1-5.1, p value =0.003), respectively. In the multivariate model, the strongest predictor of testing positive was living in a rural community, with p < 0.001 and odds ratio of 10.9 (95% CI, 3.8-31.8). These results indicate that during a low transmission period, the prevalence of asymptomatic malaria differs between depleted urban and rural forested settings, suggesting a need for strategic target intervention for the control of asymptomatic malaria.


Assuntos
COVID-19 , Malária Falciparum , Malária , Humanos , População Rural , Plasmodium falciparum , COVID-19/epidemiologia , Pandemias , Malária/epidemiologia , Florestas , Prevalência , Malária Falciparum/epidemiologia
2.
Pathogens ; 11(6)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35745507

RESUMO

Cryptosporidiosis is an intestinal disease that affects a variety of hosts including animals and humans. Since no vaccines exist against the disease till date, drug treatment is the mainstay of disease control. Nitazoxanide (NTZ) is the only FDA-approved drug for the treatment of human cryptosporidiosis. However, its efficacy in immunocompromised people such as those with AIDS, in malnourished children, or those with concomitant cryptosporidiosis is limited. In the absence of effective drugs against cryptosporidiosis, improving the efficacy of existing drugs may offer an attractive alternative. In the present work, we have assessed the potential of the cell-penetrating peptide (CPP) octaarginine (R8) to increase the uptake of NTZ. Octaarginine (R8) was synthetically attached to NTZ in an enzymatically releasable manner and used to inhibit growth of Cryptosporidium parvum in an in vitro culture system using human ileocecal adenocarcinoma (HCT-8) cell line. We observed a significant concentration-dependent increase in drug efficacy. We conclude that coupling of octaarginine to NTZ is beneficial for drug activity and it represents an attractive strategy to widen the repertoire of anti-cryptosporidial therapeutics. Further investigations such as in vivo studies with the conjugate drug will help to further characterize this strategy for the treatment of cryptosporidiosis.

3.
Crop Sci ; 60(3): 1325-1345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612294

RESUMO

Vitamin A deficiency, drought, low soil nitrogen (low-N), and Striga hermonthica parasitism of maize (Zea mays L.) cause malnutrition and food insecurity in sub-Saharan Africa. The objectives of this study were to determine combining abilities of extra-early provitamin A (PVA) lines, classify them into heterotic groups (HGs), identify testers, and determine yield stability of hybrids under contrasting environments in two trials. In Trial 1, 190 F1 hybrids plus six checks were tested under Striga-infested, drought, and stress-free environments in Nigeria from 2015-2017. In Trial 2, 35 extra-early yellow hybrids were evaluated under low-N, Striga-infested, and stress-free environments in 2018. TZEEIOR 202 and TZEEIOR 205 had PVA concentrations of 23.98 and 22.56 µg g-1. TZEEIOR 197 × TZEEIOR 205 (20.1 µg g-1) and TZEEIOR 202 × TZEEIOR 205 (22.7 µg g-1) contained about double the PVA level of the commercial check, TZEEI 58 × TZEE-Y Pop STR C5 (11.4 µg g-1). Both general (GCA) and specific (SCA) combining ability variances were significant for most agronomic traits, although GCA was larger than SCA effects, indicating GCA effects primarily controlled the inheritance of those traits. TZEEIOR 97 and TZEEIOR 197 were identified as inbred testers. TZEEIOR 197 × TZEEIOR 205 was identified as a single-cross tester and the most stable and highest-yielding hybrid across environments. TZEEIOR 202 and TZEEIOR 205 should be invaluable resources for breeding for high PVA. Provitamin A level was independent of hybrid yield potential, indicating that selection of superior hybrids with elevated PVA levels should be feasible.

4.
Ann Oncol ; 31(9): 1240-1250, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32473302

RESUMO

BACKGROUND: Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC. PATIENTS AND METHODS: Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies. RESULTS: Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years. CONCLUSION: The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Cistadenocarcinoma Seroso/genética , Feminino , Humanos , Neoplasias Ovarianas/genética , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida , Transcriptoma
5.
Hum Reprod ; 34(1): 69-78, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30428062

RESUMO

STUDY QUESTION: Does incisional endometriosis (IE) harbor somatic cancer-driver mutations? SUMMARY ANSWER: We found that approximately one-quarter of IE cases harbor somatic-cancer mutations, which commonly affect components of the MAPK/RAS or PI3K-Akt-mTor signaling pathways. WHAT IS KNOWN ALREADY: Despite the classification of endometriosis as a benign gynecological disease, it shares key features with cancers such as resistance to apoptosis and stimulation of angiogenesis and is well-established as the precursor of clear cell and endometrioid ovarian carcinomas. Our group has recently shown that deep infiltrating endometriosis (DE), a form of endometriosis that rarely undergoes malignant transformation, harbors recurrent somatic mutations. STUDY DESIGN, SIZE, DURATION: In a retrospective study comparing iatrogenically induced and endogenously occurring forms of endometriosis unlikely to progress to cancer, we examined endometriosis specimens from 40 women with IE and 36 women with DE. Specimens were collected between 2004 and 2017 from five hospital sites in either Canada, Germany or the Netherlands. IE and DE cohorts were age-matched and all women presented with histologically typical endometriosis without known history of malignancy. PARTICIPANTS/MATERIALS, SETTING, METHODS: Archival tissue specimens containing endometriotic lesions were macrodissected and/or laser-capture microdissected to enrich endometriotic stroma and epithelium and a hypersensitive cancer hotspot sequencing panel was used to assess for presence of somatic mutations. Mutations were subsequently validated using droplet digital PCR. PTEN and ARID1A immunohistochemistry (IHC) were performed as surrogates for somatic events resulting in functional loss of respective proteins. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, we detected somatic cancer-driver events in 11 of 40 (27.5%) IE cases and 13 of 36 (36.1%) DE cases, including hotspot mutations in KRAS, ERBB2, PIK3CA and CTNNB1. Heterogeneous PTEN loss occurred at similar rates in IE and DE (7/40 vs 5/36, respectively), whereas ARID1A loss only occurred in a single case of DE. While rates of detectable somatic cancer-driver events between IE and DE are not statistically significant (P > 0.05), KRAS activating mutations were more prevalent in DE. LIMITATIONS, REASONS FOR CAUTION: Detection of somatic cancer-driver events were limited to hotspots analyzed in our panel-based sequencing assay and loss of protein expression by IHC from archival tissue. Whole genome or exome sequencing, or epigenetic analysis may uncover additional somatic alterations. Moreover, because of the descriptive nature of this study, the functional roles of identified mutations within the context of endometriosis remain unclear and causality cannot be established. WIDER IMPLICATIONS OF THE FINDINGS: The alterations we report may be important in driving the growth and survival of endometriosis in ectopic regions of the body. Given the frequency of mutation in surgically displaced endometrium (IE), examination of similar somatic events in eutopic endometrium, as well as clinically annotated cases of other forms of endometriosis, in particular endometriomas that are most commonly linked to malignancy, is warranted. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by a Canadian Cancer Society Impact Grant [701603, PI Huntsman], Canadian Institutes of Health Research Transitional Open Operating Grant [MOP-142273, PI Yong], the Canadian Institutes of Health Research Foundation Grant [FDN-154290, PI Huntsman], the Canadian Institutes of Health Research Project Grant [PJT-156084, PIs Yong and Anglesio], and the Janet D. Cottrelle Foundation through the BC Cancer Foundation [PI Huntsman]. D.G. Huntsman is a co-founder and shareholder of Contextual Genomics Inc., a for profit company that provides clinical reporting to assist in cancer patient treatment. R. Aguirre-Hernandez, J. Khattra and L.M. Prentice have a patent MOLECULAR QUALITY ASSURANCE METHODS FOR USE IN SEQUENCING pending and are current (or former) employees of Contextual Genomics Inc. The remaining authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Endometriose/patologia , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Neoplasias/genética , Adulto , Biomarcadores Tumorais/metabolismo , Canadá , Progressão da Doença , Endometriose/etiologia , Endométrio/patologia , Endométrio/cirurgia , Feminino , Alemanha , Humanos , Doença Iatrogênica , Pessoa de Meia-Idade , Mutação , Neoplasias/patologia , Países Baixos , Estudos Retrospectivos , Transdução de Sinais/genética
6.
Ann Oncol ; 29(5): 1180-1188, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29432521

RESUMO

Background: We have previously developed and confirmed a pragmatic molecular classifier for endometrial cancers; ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer). Inspired by the Cancer Genome Atlas, ProMisE identifies four prognostically distinct molecular subtypes and can be applied to diagnostic specimens (biopsy/curettings) enabling earlier informed decision-making. We have strictly adhered to the Institute of Medicine (IOM) guidelines for the development of genomic biomarkers, and herein present the final validation step of a locked-down classifier before clinical application. Patients and methods: We assessed a retrospective cohort of women from the Tübingen University Women's Hospital treated for endometrial carcinoma between 2003 and 2013. Primary outcomes of overall, disease-specific, and progression-free survival were evaluated for clinical, pathological, and molecular features. Results: Complete clinical and molecular data were evaluable from 452 women. Patient age ranged from 29 to 93 (median 65) years, and 87.8% cases were endometrioid histotype. Grade distribution included 282 (62.4%) G1, 75 (16.6%) G2, and 95 (21.0%) G3 tumors. 276 (61.1%) patients had stage IA disease, with the remaining stage IB [89 (19.7%)], stage II [26 (5.8%)], and stage III/IV [61 (13.5%)]. ProMisE molecular classification yielded 127 (28.1%) MMR-D, 42 (9.3%) POLE, 55 (12.2%) p53abn, and 228 (50.4%) p53wt. ProMisE was a prognostic marker for progression-free (P = 0.001) and disease-specific (P = 0.03) survival even after adjusting for known risk factors. Concordance between diagnostic and surgical specimens was highly favorable; accuracy 0.91, κ 0.88. Discussion: We have developed, confirmed, and now validated a pragmatic molecular classification tool (ProMisE) that provides consistent categorization of tumors and identifies four distinct prognostic molecular subtypes. ProMisE can be applied to diagnostic samples and thus could be used to inform surgical procedure(s) and/or need for adjuvant therapy. Based on the IOM guidelines this classifier is now ready for clinical evaluation through prospective clinical trials.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias do Endométrio/patologia , Endométrio/patologia , Técnicas de Diagnóstico Molecular/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biópsia , Intervalo Livre de Doença , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
7.
Int J Phytoremediation ; 20(13): 1346-1353, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30666896

RESUMO

Contaminated soils are a serious environmental problem in developing countries. Poor disposal of used engine oil from vehicles is a source of soil contamination in Buea, Cameroon. This study was conducted in the University of Buea Teaching and Research Farm to determine the ability of two sedges (Kyllinga erecta Schumach and Cyperus rotundus Linn.) to remediate crop land contaminated with used engine oil. The experiment consisted of the two sedges and the following used oil levels (v/wt): 0, 5, 10, 20, 40 and 60 ml/kg of soil. Control treatments with 0 and 60 ml of used engine oil/kg of soil without the sedges were also included. The plant (roots and shoots) and soil samples were analyzed for heavy metal contents using the Inductively Coupled Plasma Optical Mass Spectrometry analytical package for ultra-low detection and high precision. The root and shoot dry biomass of both sedges decreased with an increase in soil contamination. Cyperus rotundus accumulated high concentrations of Cr (mean = 64.8 ± 19.5 ppm) and Cd (mean =1.2 ± 0.2 ppm) in its roots. Kyllinga erecta had the potential to extract Sn, Cd, Mn, Sr and Mo on soils contaminated with used oil at 60 ml/kg. Cyperus rotundus had phytostabilisation potential for Cd at concentrations of used oil ≤20 ml/kg and Rb at 20 ml/kg. The sedge also had phytoextraction potential for Cr and Rb on soils contaminated with used oil at concentrations up to 20 ml/kg. Therefore, the use of indigenous plants adapted to tropical environments could be a possible option for the sustainable remediation of soils contaminated with heavy metals from used engine oil.


Assuntos
Cyperus , Metais Pesados/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Camarões , Solo/química
8.
Child Care Health Dev ; 43(5): 645-662, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28543609

RESUMO

BACKGROUND: Serious chronic illness can have a detrimental effect on school attendance, participation and engagement, leaving affected students at risk of failing to meet their developmental potential. An improved understanding of factors that help to explain or mitigate this risk can help educators and health professionals deliver the most effective support. This meta-review critiqued the available evidence examining the link between six chronic illnesses (asthma, cancer, chronic kidney diseases, heart diseases, cystic fibrosis and gastrointestinal diseases) and children's and adolescents' school experiences and outcomes, as well as investigating the medical, school, psychosocial and sociodemographic factors that are linked to poorer or better school outcomes. METHODS: We searched CINAHL, Cochrane Database, EMBASE, ERIC, MEDLINE, ProQuest Theses and Dissertations, and PsycINFO (2000-2015). Systematic and narrative reviews, and meta-analyses, of original studies examining students' subjective school experiences and objective school outcomes were eligible. We used the Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria to critically appraise all systematic reviews. The Grading of Recommendations Assessment, Development, and Evaluation system guided our recommendations for practice and research. RESULTS: Eighteen reviews of 172 studies including more than 40 000 students were eligible. Therefore, we chose to conduct a meta-review to provide an overview of the literature on the relationship between chronic illness and school experiences and outcomes. We also explored the associated medical, school, psychosocial and sociodemographic factors affecting the relationship between illness and school experiences and outcomes. CONCLUSION: Students with chronic illness demonstrate mixed school experiences and outcomes that are often worse than students without chronic illness. Modifiable factors, such as students' engagement with school, may be novel yet appropriate targets of educational support to ensure that these students reach their full schooling potential.


Assuntos
Sucesso Acadêmico , Doença Crônica/psicologia , Instituições Acadêmicas , Estudantes/psicologia , Absenteísmo , Adaptação Psicológica , Adolescente , Criança , Humanos , Relações Interpessoais , Serviços de Saúde Escolar , Estudantes/estatística & dados numéricos
9.
Int J Phytoremediation ; 16(3): 302-19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24912226

RESUMO

Phytoremediation is a promising option for reclaiming soils contaminated with toxic metals, using plants with high potentials for extraction, stabilization and hyperaccumulation. This study was conducted in Cameroon, at the Bassa Industrial Zone of Douala in 2011, to assess the total content of 19 heavy metals and 5 other elements in soils and phytoremediation potential of 12 weeds. Partial extraction was carried out in soil, plant root and shoot samples. Phytoremediation potential was evaluated in terms of the Biological Concentration Factor, Translocation Factor and Biological Accumulation Coefficient. The detectable content of the heavy metals in soils was Cu:70-179, Pb:8-130, Zn:200-971, Ni:74-296, Co:31-90, Mn:1983-4139, V:165-383, Cr:42-1054, Ba:26-239, Sc:21-56, Al:6.11-9.84, Th:7-22, Sr:30-190, La:52-115, Zr:111-341, Y:10-49, Nb:90-172 in mg kg(-1), and Ti:2.73-4.09 and Fe:12-16.24 in wt%. The contamination index revealed that the soils were slightly to heavily contaminated while the geoaccumulation index showed that the soils ranged from unpolluted to highly polluted. The concentration of heavy metals was ranked as Zn > Ni > Cu > V > Mn > Sc > Co > Pb and Cr in the roots and Mn > Zn > Ni > Cu > Sc > Co > V > Pb > Cr > Fe in the shoots. Dissotis rotundifolia and Kyllinga erecta had phytoextraction potentials for Pb and Paspalum orbicularefor Fe. Eleusine indica and K. erecta had phytostabilisation potential for soils contaminated with Cu and Pb, respectively.


Assuntos
Metais Pesados/metabolismo , Plantas Daninhas/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Transporte Biológico , Camarões , Fenômenos Químicos , Monitoramento Ambiental , Resíduos Industriais , Metais Pesados/análise , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Solo/química , Poluentes do Solo/análise
10.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 4974-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271431

RESUMO

Neutrophil capture on inflamed endothelium is controlled by dynamic regulation of the integrin CD11a/CD18 (LFA-1). Small molecules, antibodies, and certain divalent cations binding to specific epitopes on the integrin are able to stabilize either a closed (low affinity) or open (high affinity) state. To determine the relationship between LFA-1 conformation and affinity for ICAM-1 we assembled a cell-free system consisting of CD11a/CD18 heterodimer adhered to latex microspheres. The kinetics of dimeric ICAM-1 binding to the LFA-1 on the microspheres was measured via flow cytometry and a real time conformational shift into a lower affinity state was observed by addition of a small molecule inhibitor.

11.
Appl Microbiol Biotechnol ; 56(3-4): 425-30, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11549014

RESUMO

The cysteine desulfhydrase gene of Treponema denticola was over-expressed in Escherichia coli to produce sulfide under aerobic conditions and to precipitate metal sulfide complexes on the cell wall. When grown in a defined salts medium supplemented with cadmium and cysteine, E. coli producing cysteine desulfhydrase secreted sulfide and removed nearly all of the cadmium from solution after 48 h. A control strain produced significantly less sulfide and removed significantly less cadmium. Measurement of acid-labile sulfide and energy dispersive X-ray spectroscopy indicated that cadmium was precipitated as cadmium sulfide. Without supplemental cysteine, both the E. coli producing cysteine desulfhydrase and the control E. coli demonstrated minimal cadmium removal.


Assuntos
Cádmio/metabolismo , Cistationina gama-Liase/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Sulfetos/metabolismo , Treponema/genética , Aerobiose , Biotecnologia/métodos , Precipitação Química , Cistationina gama-Liase/genética , Escherichia coli/metabolismo , Engenharia Genética , Plasmídeos/genética , Treponema/enzimologia
12.
Eff Clin Pract ; 4(3): 105-11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11434073

RESUMO

CONTEXT: Using a patient and clinician educational intervention, we successfully reduced antibiotic use for uncomplicated acute bronchitis. The impact of this intervention on patient satisfaction is not known. OBJECTIVE: To evaluate whether a strategy for reducing antibiotic use in acute bronchitis affects satisfaction among adult patients. DESIGN: Telephone survey administered 1 to 4 weeks after an office visit for acute bronchitis. SETTING: Two outpatient clinics belonging to a group-model HMO in the Denver, Colorado, metropolitan area. The intervention clinic had received a patient and office-based educational intervention that successfully reduced antibiotic prescribing for acute bronchitis during the previous winter. The control clinic received only the office-based materials, an intervention that did not reduce antibiotic prescribing. OUTCOME: Overall satisfaction with the episode of care. RESULTS: Antibiotics were prescribed to 64% and 85% of survey respondents at the intervention (n = 102) and control clinics (n = 164), respectively (P < 0.001). Patient satisfaction with the visit did not differ between intervention and control clinics (69% of intervention and 63% of control clinic patients reported very good or excellent satisfaction, P > 0.2). After adjustment for patient age, sex, duration of illness before the visit, reason for visit, and clinician specialty, there was no difference between intervention and control clinics in the proportion of patients reporting very good or excellent satisfaction (adjusted relative risk for high satisfaction at the intervention clinic, 1.1 [95% CI, 0.81 to 1.3]). CONCLUSION: A patient- and clinician-oriented educational intervention that reduces antibiotic treatment of adults with uncomplicated acute bronchitis does not appear to reduce satisfaction with care.


Assuntos
Antibacterianos/uso terapêutico , Bronquite/tratamento farmacológico , Uso de Medicamentos , Satisfação do Paciente/estatística & dados numéricos , Padrões de Prática Médica , Doença Aguda/terapia , Adolescente , Adulto , Idoso , Assistência Ambulatorial , Prescrições de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários , Estados Unidos
13.
Cancer Epidemiol Biomarkers Prev ; 10(6): 687-96, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11401920

RESUMO

Blood samples are an excellent source of large amounts of genomic DNA. However, alternative sources are often needed in epidemiological studies because of difficulties in obtaining blood samples. This report evaluates the buccal cytobrush and alcohol-containing mouthwash protocols for collecting DNA by mail. Several DNA extraction techniques are also evaluated. The study was conducted in two phases. In phase 1, we compared cytobrush and mouthwash samples collected by mail in two different epidemiological studies: (a) cytobrush samples (n = 120) from a United States case-control study of breast cancer; and (b) mouthwash samples (n = 40) from a prospective cohort of male United States farmers. Findings from phase 1 were confirmed in phase 2, where we randomized cytobrush (n = 28) and mouthwash (n = 25) samples among participants in the breast cancer study to directly compare both collection methods. The median human DNA yield determined by hybridization with a human DNA probe from phenol-chloroform extracts was 1.0 and 1.6 microg/2 brushes for phases 1 and 2, respectively, and 27.5 and 16.6 microg/mouthwash sample for phases 1 and 2, respectively. Most (94-100%) mouthwash extracts contained high molecular weight DNA (>23 kb), in contrast to 55-61% of the brush extracts. PCR success rates for amplification of beta-globin gene fragments (268, 536, and 989 bp) were similar for cytobrush and mouthwash phenol-chloroform extracts (range, 94.4-100%). Also, we obtained high success rates in determining the number of CAG repeats in the androgen receptor gene, characterizing tetranucleotide microsatellites in six gene loci, and screening for mutations in the BRCA1/2 genes in a subset of phenol-chloroform DNA extracts. Relative to DNA extracted by phenol-chloroform from cytobrush samples, DNA extracted by NaOH had lower molecular weight, decreased PCR success rates for most assays performed, and unreliably high spectrophotometer readings for DNA yields. In conclusion, although DNA isolated from either mouthwash or cytobrush samples collected by mail from adults is adequate for a wide range of PCR-based assays, a single mouthwash sample provides substantially larger amounts and higher molecular weight DNA than two cytobrush samples.


Assuntos
DNA/análise , Estudos Epidemiológicos , Reação em Cadeia da Polimerase , Adulto , Idoso , Neoplasias da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Antissépticos Bucais , Reprodutibilidade dos Testes , Manejo de Espécimes
14.
Biophys J ; 80(3): 1547-56, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11222315

RESUMO

Acoustically active microbubbles are used for contrast-enhanced ultrasound assessment of organ perfusion. In regions of inflammation, contrast agents are captured and phagocytosed by activated neutrophils adherent to the venular wall. Using direct optical observation with a high-speed camera and acoustical interrogation of individual bubbles and cells, we assessed the physical and acoustical responses of both phagocytosed and free microbubbles. Optical analysis of bubble radial oscillations during insonation demonstrated that phagocytosed microbubbles experience viscous damping within the cytoplasm and yet remain acoustically active and capable of large volumetric oscillations during an acoustic pulse. Fitting a modified version of the Rayleigh-Plesset equation that describes mechanical properties of thin shells to optical radius-time data of oscillating bubbles provided estimates of the apparent viscosity of the intracellular medium. Phagocytosed microbubbles experienced a viscous damping approximately sevenfold greater than free microbubbles. Acoustical comparison between free and phagocytosed microbubbles indicated that phagocytosed microbubbles produce an echo with a higher mean frequency than free microbubbles in response to a rarefaction-first single-cycle pulse. Moreover, this frequency increase is predicted using the modified Rayleigh-Plesset equation. We conclude that contrast-enhanced ultrasound can detect distinct acoustic signals from microbubbles inside of neutrophils and may provide a unique tool to identify activated neutrophils at sites of inflammation.


Assuntos
Neutrófilos/fisiologia , Fagocitose , Meios de Contraste , Elasticidade , Humanos , Técnicas In Vitro , Cinética , Modelos Biológicos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/ultraestrutura , Oscilometria , Fosfolipídeos , Viscosidade
15.
Cancer Epidemiol Biomarkers Prev ; 9(11): 1199-204, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11097227

RESUMO

Tobacco smoking is a strong cause of lung cancer. However, because only a small proportion of smokers develop the disease, other factors, including genetic susceptibility, may be important in determining lung cancer risk. Polymorphisms in the TP53 tumor suppressor gene and HRAS1 proto-oncogene have been associated in some studies with this cancer; we sought to replicate these associations in an ethnically diverse population in Hawaii. We conducted a population-based case-control study among 334 incident lung cancer cases and 446 controls of Caucasian, Japanese, or Native Hawaiian origin. In-person interviews collected detailed information on lifestyle risk factors. DNA was extracted from peripheral blood leukocytes, and genotyping was performed using a PCR-based assay for the TP53 codon 72 polymorphism and Southern blot analysis and PCR for allelic polymorphisms in the HRAS1 minisatellite. Logistic regression analyses were used to compute odds ratios (ORs) and 95% confidence intervals (CIs) adjusting for smoking and other risk factors. The presence of two rare HRAS1 alleles was associated with a 2.2-fold (95% CI, 1.0-5.0) increased lung cancer risk for all ethnic groups combined. The association was present in Native Hawaiians (OR, 5.2; 95% CI, 1.1-24.4) and was suggested for Japanese (OR, 2.8; 95% CI, 0.6-12.5); no association was observed in Caucasians (OR, 0.8; 95% CI, 0.2-3.6). This association was also observed for each lung cancer cell type. The presence of only one rare allele did not increase risk for any ethnic group or cell type. No significant association was found between the TP53 codon 72 polymorphism and lung cancer [OR, 1.4 (95% CI, 0.8-2.4) for the Pro/Pro genotype compared with the Arg/Arg genotype]. This study suggests that the presence of two rare HRAS1 alleles confers an increased lung cancer risk in Native Hawaiians and Japanese but possibly not in Caucasians. The amino acid replacement of arginine by proline at codon 72 of TP53 appears not to be important in determining lung cancer risk in this population.


Assuntos
Genes p53/genética , Genes ras/genética , Neoplasias Pulmonares/etnologia , Neoplasias Pulmonares/genética , Polimorfismo Genético , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Etnicidade , Feminino , Humanos , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Proto-Oncogene Mas , Fatores de Risco , População Branca/genética
16.
Appl Environ Microbiol ; 66(10): 4497-502, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11010904

RESUMO

The conversion of sulfate to an excess of free sulfide requires stringent reductive conditions. Dissimilatory sulfate reduction is used in nature by sulfate-reducing bacteria for respiration and results in the conversion of sulfate to sulfide. However, this dissimilatory sulfate reduction pathway is inhibited by oxygen and is thus limited to anaerobic environments. As an alternative, we have metabolically engineered a novel aerobic sulfate reduction pathway for the secretion of sulfides. The assimilatory sulfate reduction pathway was redirected to overproduce cysteine, and excess cysteine was converted to sulfide by cysteine desulfhydrase. As a potential application for this pathway, a bacterium was engineered with this pathway and was used to aerobically precipitate cadmium as cadmium sulfide, which was deposited on the cell surface. To maximize sulfide production and cadmium precipitation, the production of cysteine desulfhydrase was modulated to achieve an optimal balance between the production and degradation of cysteine.


Assuntos
Compostos de Cádmio/metabolismo , Cádmio/metabolismo , Cistationina gama-Liase/genética , Escherichia coli/metabolismo , Engenharia Genética , Sulfatos/metabolismo , Sulfetos/metabolismo , Treponema/enzimologia , Treponema/genética , Aerobiose , Anaerobiose , Clonagem Molecular/métodos , Cistationina gama-Liase/metabolismo , Escherichia coli/genética , Cinética , Oxirredução , Oxigênio/farmacologia , Plasmídeos , Reação em Cadeia da Polimerase/métodos
17.
Am Heart J ; 140(3): 385-94, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10966535

RESUMO

BACKGROUND: Recent studies have reported that negative T waves in the setting of acute coronary events are associated with Thrombolysis In Myocardial Infarction flow grade 3 in the infarct-related artery and with improved parameters of ventricular function rather than with ischemia. METHODS: Patients enrolled in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) angiographic substudy (ie, patients with acute infarction randomly assigned to one of 4 thrombolytic regimens who then underwent coronary angiography) were included in this study if they survived at least 24 hours and had no confounding electrocardiographic factors (n = 1505). RESULTS: More patients had negative T waves develop (NT group, n = 938 [62%]) than not (PT group, n = 567 [38%]). Peak creatine kinase MB, time to thrombolysis, and randomization to accelerated alteplase were no different between the groups. Thirty days after admission, 12 patients in the NT group had died versus 25 patients in the PT group (1.3% vs. 4.4%; P <.001; odds ratio for negative T waves 0.28; 95% confidence interval 0.14-0.56). The difference persisted when only patients who survived at least 3 days were analyzed. After adjusting for relevant covariates (including presence of new Q waves in the follow-up electrocardiogram), negative T waves were an independent predictor for survival (P =. 007; odds ratio for negative T waves 0.38; 95% confidence interval 0. 18-0.78). Patients in the NT group were 35% more likely to have achieved patency of the infarct-related artery, although this difference was not statistically significant. CONCLUSIONS: Negative T waves shortly after acute myocardial infarction treated with thrombolysis were markers for improved 30-day survival rate. This finding merits prospective testing.


Assuntos
Eletrocardiografia/classificação , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/diagnóstico , Adulto , Idoso , Biomarcadores/análise , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Taxa de Sobrevida
18.
Cancer Epidemiol Biomarkers Prev ; 9(2): 181-4, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10698479

RESUMO

Myeloperoxidase, which is released from neutrophils in response to various pulmonary insults including tobacco smoke, is suspected to play a carcinogenic role in the lung. A G-to-A substitution polymorphism in the promoter region of the MPO gene has been suggested in in vitro studies to decrease gene transcription. We tested the association of this polymorphism with lung cancer in a population-based case-control study of 323 cases and 437 controls of Caucasian, Japanese, or Native Hawaiian ancestry in Hawaii. We found a marked difference in the frequency of the variant A allele among Caucasians (26%), Japanese (17%), and Hawaiians (13%). Overall, the variant allele was somewhat less frequent in cases than controls (P = 0.13). Individuals with the A/A genotype were found to be at a 50% decreased risk compared to those with two G alleles (95% confidence interval, 0.2-1.3). Although not statistically significant, this inverse association was suggested in both sexes and two of the three ethnic groups studied. Heterozygotes were at no decreased risk. Further work needs to clarify the functional relevance of the A allele in vivo and to confirm the inverse association of the A/A genotype with lung cancer in large epidemiological studies.


Assuntos
Neoplasias Pulmonares/genética , Peroxidase/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Feminino , Havaí/epidemiologia , Humanos , Japão/etnologia , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Peroxidase/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Risco , População Branca/genética
19.
Cancer Res ; 59(13): 3045-8, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10397241

RESUMO

The NAD(P)H:quinone oxidoreductase gene, NQO1, often carries a C-->T transition at bp 609, which has been associated with a reduced enzymatic activity and which may result in altered metabolic activation of tobacco smoke procarcinogens. We tested the association of this polymorphism with lung cancer risk in a population-based case-control study of 327 cases and 440 controls of Caucasian, Japanese, or Native Hawaiian ancestry in Hawaii. We found a notable difference in the frequency of the variant allele among Japanese (38%), Caucasians (20%), and Hawaiians (22%). Overall, the variant allele was less frequent in cases than in controls (P = 0.03). A significant inverse association was found in Japanese, with adjusted odds ratios of 0.8 (95% confidence interval, 0.4-1.5) and 0.3 (0.1-0.7) for the heterozygous and homozygous variant genotypes, respectively, compared with the homozygous wild-type genotype (P for genetic trend, 0.02). The association did not reach statistical significance in Caucasians and Hawaiians but was in the same direction.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , NAD(P)H Desidrogenase (Quinona)/genética , Polimorfismo Genético , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Citosina , Feminino , Variação Genética , Genótipo , Havaí/epidemiologia , Humanos , Japão/etnologia , Masculino , Razão de Chances , Mutação Puntual , Sistema de Registros , Medição de Risco , Fatores de Risco , Timina , População Branca/genética
20.
JAMA ; 281(16): 1512-9, 1999 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10227321

RESUMO

CONTEXT: The emergence and spread of antibiotic-resistant Streptococcus pneumoniae in US communities is due, in part, to the excessive use of antibiotics for acute respiratory tract infections. OBJECTIVE: To decrease total antibiotic use for uncomplicated acute bronchitis in adults. DESIGN: Prospective, nonrandomized controlled trial, including baseline (November 1996-February 1997) and study (November 1997-February 1998) periods. SETTING: Four selected primary care practices belonging to a group-model health maintenance organization in the Denver, Colo, metropolitan area. PARTICIPANTS: Consecutive adults diagnosed as having uncomplicated acute bronchitis. A total of 2462 adults were included at baseline and 2027 adults were included in the study. Clinicians included 56 physicians, 28 physician assistants or nurse practitioners, and 9 registered nurses. INTERVENTION: The full intervention site received household and office-based patient educational materials, as well as a clinician intervention consisting of education, practice-profiling, and academic detailing. A limited intervention site received only office-based educational materials, and control sites provided usual care. MAIN OUTCOME MEASURE: Antibiotic prescriptions for uncomplicated acute bronchitis during baseline and study periods. RESULTS: Antibiotic prescription rates for uncomplicated acute bronchitis were similar at all 4 sites during the baseline period. During the study period, there was a substantial decline in antibiotic prescription rates at the full intervention site (from 74% to 48% [P = .003]), but not at the control and limited intervention sites (78% to 76% [P = .81] and 82% to 77% [P = .68], respectively). Compared with control sites, changes in nonantibiotic prescriptions (inhaled bronchodilators, cough suppressants, and analgesics) were not significantly different for intervention sites. Return office visits (within 30 days of the incident visit) for bronchitis or pneumonia did not change significantly for any of the sites. CONCLUSIONS: Antibiotic treatment of adults diagnosed as having uncomplicated acute bronchitis can be safely reduced using a combination of patient and clinician interventions.


Assuntos
Antibacterianos/uso terapêutico , Bronquite/tratamento farmacológico , Educação de Pacientes como Assunto , Doença Aguda , Adulto , Idoso , Assistência Ambulatorial , Uso de Medicamentos/estatística & dados numéricos , Feminino , Sistemas Pré-Pagos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Visita a Consultório Médico/estatística & dados numéricos , Estudos Prospectivos
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