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1.
J Econ Entomol ; 109(1): 188-94, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26476558

RESUMEN

The western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a recent pest of corn, dry,and snap beans, in the Great Lakes region, and best practices for its management in beans need to be established.Insecticide efficacy and application timing field studies, conducted in 2011­2013, determined that lambda-cyhalothrin and chlorantraniliprole were capable of reducing western bean cutworm feeding damage in dry beans from 2.3 to 0.4% in preharvest samples, and in snap beans from 4.8 to 0.1% of marketable pods, respectively. The best application timing in dry beans was determined to be 4­18 d after 50% egg hatch. No economic benefit was found when products were applied to dry beans, and despite high artificial inoculation rates, damage to marketable yield was relatively low. Thiamethoxam, methoxyfenozide, and spinetoram were also found to be effective at reducing western bean cutworm damage in dry bean to as low as 0.3% compared to an untreated control with 2.5% damaged pods. In snap beans, increased return on investment between CAD$400 and CAD$600 was seen with multiple applications of lambda-cyhalothrin, and with chlorantraniliprole applied 4 d after egg mass infestation.


Asunto(s)
Control de Insectos , Insecticidas , Mariposas Nocturnas , Nitrilos , Piretrinas , ortoaminobenzoatos , Animales , Great Lakes Region , Larva , Mariposas Nocturnas/crecimiento & desarrollo , Phaseolus/fisiología
2.
Antimicrob Agents Chemother ; 59(1): 365-71, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25367901

RESUMEN

The resistance of Plasmodium falciparum to some antimalarial drugs is linked to single-nucleotide polymorphisms (SNPs). Currently, there are no methods for the identification of resistant parasites that are sufficiently simple, cheap, and fast enough to be performed at point-of-care, i.e., in local hospitals where drugs are prescribed. Primer extension methods (PEXT) were developed to identify 4 SNPs in P. falciparum positioned at amino acids 86, 184, and 1246 of the P. falciparum multidrug resistance 1 gene (pfmdr1) and amino acid 76 of the chloroquine resistance transporter gene (pfcrt). The PEXT products were visualized by a nucleic acid lateral flow immunoassay (NALFIA) with carbon nanoparticles as the detection labels. PCR-PEXT-NALFIAs showed good correlation to the reference methods, quantitative PCR (qPCR) or direct amplicon sequence analysis, in an initial open-label evaluation with 17 field samples. The tests were further evaluated in a blind study design in a set of 150 patient isolates. High specificities of 98 to 100% were found for all 4 PCR-PEXT genotyping assays. The sensitivities ranged from 75% to 100% when all PEXT-positive tests were considered. A number of samples with a low parasite density were successfully characterized by the reference methods but failed to generate a result in the PCR-PEXT-NALFIA, particularly those samples with microscopy-negative subpatent infections. This proof-of principle study validates the use of PCR-PEXT-NALFIA for the detection of resistance-associated mutations in P. falciparum, particularly for microscopy-positive infections. Although it requires a standard thermal cycler, the procedure is cheap and rapid and thus a potentially valuable tool for point-of-care detection in developing countries.


Asunto(s)
Resistencia a Medicamentos/genética , Inmunoensayo/métodos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa/métodos , Antimaláricos , Cloroquina/uso terapéutico , Cartilla de ADN/genética , ADN Protozoario/genética , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Proteínas de Transporte de Membrana/genética , Plasmodium falciparum/efectos de los fármacos , Polimorfismo de Nucleótido Simple , Proteínas Protozoarias/genética
3.
Br J Cancer ; 108(10): 2045-55, 2013 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-23652307

RESUMEN

BACKGROUND: Autoantibodies have been detected in sera before diagnosis of cancer leading to interest in their potential as screening/early detection biomarkers. As we have found autoantibodies to MUC1 glycopeptides to be elevated in early-stage breast cancer patients, in this study we analysed these autoantibodies in large population cohorts of sera taken before cancer diagnosis. METHODS: Serum samples from women who subsequently developed breast cancer, and aged-matched controls, were identified from UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) and Guernsey serum banks to formed discovery and validation sets. These were screened on a microarray platform of 60mer MUC1 glycopeptides and recombinant MUC1 containing 16 tandem repeats. Additional case-control sets comprised of women who subsequently developed ovarian, pancreatic and lung cancer were also screened on the arrays. RESULTS: In the discovery (273 cases, 273 controls) and the two validation sets (UKCTOCS 426 cases, 426 controls; Guernsey 303 cases and 606 controls), no differences were found in autoantibody reactivity to MUC1 tandem repeat peptide or glycoforms between cases and controls. Furthermore, no differences were observed between ovarian, pancreatic and lung cancer cases and controls. CONCLUSION: This robust, validated study shows autoantibodies to MUC1 peptide or glycopeptides cannot be used for breast, ovarian, lung or pancreatic cancer screening. This has significant implications for research on the use of MUC1 in cancer detection.


Asunto(s)
Autoanticuerpos/sangre , Neoplasias de la Mama/diagnóstico , Carcinoma/diagnóstico , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Mucina-1/inmunología , Neoplasias Ováricas/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Neoplasias de la Mama/sangre , Neoplasias de la Mama/inmunología , Carcinoma/sangre , Carcinoma/inmunología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Glicopéptidos/inmunología , Humanos , Inmunoensayo , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/inmunología , Persona de Mediana Edad , Neoplasias Ováricas/sangre , Neoplasias Ováricas/inmunología , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/inmunología
4.
ESMO Open ; 7(4): 100530, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35921760

RESUMEN

BACKGROUND: Activation of leukemia inhibitory factor (LIF) is linked to an immunosuppressive tumor microenvironment (TME), with a strong association between LIF expression and tumor-associated macrophages (TAMs). MSC-1 (AZD0171) is a humanized monoclonal antibody that binds with high affinity to LIF, promoting antitumor inflammation through TAM modulation and cancer stem cell inhibition, slowing tumor growth. In this phase I, first-in-human, open-label, dose-escalation study, MSC-1 monotherapy was assessed in patients with advanced, unresectable solid tumors. MATERIALS AND METHODS: Using accelerated-titration dose escalation followed by a 3 + 3 design, MSC-1 doses of 75-1500 mg were administered intravenously every 3 weeks (Q3W) until progression or unmanageable toxicity. Additional patients were enrolled in selected cohorts to further evaluate safety, pharmacokinetics (PK), and pharmacodynamics after escalation to the next dose had been approved. The primary objective was characterizing safety and determining the recommended phase II dose (RP2D). Evaluating antitumor activity and progression-free survival (PFS) by RECIST v1.1, PK and immunogenicity were secondary objectives. Exploratory objectives included pharmacodynamic effects on circulating LIF and TME immune markers. RESULTS: Forty-one patients received treatment. MSC-1 monotherapy was safe and well tolerated at all doses, with no dose-limiting toxicities. The maximum tolerated dose was not reached and the RP2D was determined to be 1500 mg Q3W. Almost half of the patients had treatment-related adverse events (TRAEs), with no apparent trends across doses; no patients withdrew due to TRAEs. There were no objective responses; 23.7% had stable disease for ≥2 consecutive tumor assessments. Median PFS was 5.9 weeks; 23.7% had PFS >16 weeks. On-treatment changes in circulating LIF and TME signal transducers and activators of transcription 3 signaling, M1:M2 macrophage populations, and CD8+ T-cell infiltration were consistent with the hypothesized mechanism of action. CONCLUSIONS: MSC-1 was very well tolerated across doses, with prolonged PFS in some patients. Biomarker and preclinical data suggest potential synergy with checkpoint inhibitors.


Asunto(s)
Antineoplásicos , Neoplasias , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados , Humanos , Dosis Máxima Tolerada , Microambiente Tumoral
5.
Environ Entomol ; 38(3): 708-14, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19508779

RESUMEN

Coccinella septempunctata L. and Harmonia axyridis Pallas are key natural enemies of soybean aphid, Aphis glycines Matsumura, in North America. Third instars, adult females, and adult males of both C. septempunctata and H. axyridis exhibited a type II functional response for predation toward adult soybean aphids at 26 +/- 1 degrees C. In C. septempunctata, the functional response curve of adult males differed from those of third instars and adult females, but there was no difference between third instars and adult females. In H. axyridis, the functional response curves of larvae, adult females, and adult males all differed significantly. Third instars and adult females consumed significantly more soybean aphids than did adult males at prey densities of 150 and 180 aphids per arena for C. septempunctata and at prey densities of 60, 90, 120, 150, and 180 aphids per arena for H. axyridis. The theoretical maximum daily predation rate of adult aphids by C. septempunctata was predicted to be 204 per third instar, 277 per adult female, and 166 per adult male, and 244, 156, and 73, respectively, for H. axyridis. Third instars and adult females of both species consumed significantly more aphids than did adult males on soybean plants with the recommended action threshold of 250 soybean aphids per plant. Both C. septempunctata and H. axyridis have high predation capacities and are important in suppressing soybean aphid populations.


Asunto(s)
Áfidos , Escarabajos , Glycine max , Control Biológico de Vectores , Conducta Predatoria , Animales , Femenino , Masculino
6.
Environ Entomol ; 37(4): 973-9, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18801263

RESUMEN

Harmonia axyridis Pallas is an introduced lady beetle common in eastern North American agroecosystems. Two-choice behavioral bioassays were performed to determine whether visual and olfactory stimuli from prey and host habitats could elicit taxis in wild-collected H. axyridis adults and whether beetles exhibit a preference among stimuli. Soybean aphid (Aphis glycines Matsumura) spends much of the year in agricultural hedgerows residing on buckthorn (Rhamnus cathartica L), and H. axyridis is frequently observed feeding on aphids in this habitat. Olfactory bioassays were performed in a Y-tube olfactometer and tested the response of beetles to the odor of buckthorn leaves, apple leaves (Malus domestica Borkh.), and buckthorn leaves both naturally and artificially infested with A. glycines. No differences were observed between the numbers of beetles moving toward the odor of buckthorn artificially infested with A. glycines and uninfested buckthorn, but more beetles preferred naturally infested buckthorn over uninfested buckthorn. Visual bioassays were performed in an acrylic tube arena,and tested beetle response to silhouettes and to apple and buckhorn leaves. Beetles were significantly more likely to choose silhouettes over blank space in visual trials. Significantly more beetles moved toward buckthorn leaves than blank space, but beetles did not discern between apple and buckthorn until olfactory cues were also included. This study lays the foundation for future work examining the response of H. axyridis to visual and olfactory cues in Ontario agroecosystems, which could help enhance effectiveness of H. axyridis as a biological control and mitigate its impacts as a pest species.


Asunto(s)
Conducta Animal , Escarabajos/fisiología , Señales (Psicología) , Olfato/fisiología , Animales , Áfidos/fisiología , Conducta de Elección , Ecosistema , Conducta Alimentaria , Malus/química , Odorantes , Estimulación Luminosa , Rhamnus/química , Estimulación Química
7.
Oncogene ; 36(5): 606-617, 2017 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-27775079

RESUMEN

Medulloblastoma (MB), the most common malignant paediatric brain tumor, is currently treated using a combination of surgery, craniospinal radiotherapy and chemotherapy. Owing to MB stem cells (MBSCs), a subset of MB patients remains untreatable despite standard therapy. CD133 is used to identify MBSCs although its functional role in tumorigenesis has yet to be determined. In this work, we showed enrichment of CD133 in Group 3 MB is associated with increased rate of metastasis and poor clinical outcome. The signal transducers and activators of transcription-3 (STAT3) pathway are selectively activated in CD133+ MBSCs and promote tumorigenesis through regulation of c-MYC, a key genetic driver of Group 3 MB. We screened compound libraries for STAT3 inhibitors and treatment with the selected STAT3 inhibitors resulted in tumor size reduction in vivo. We propose that inhibition of STAT3 signaling in MBSCs may represent a potential therapeutic strategy to treat patients with recurrent MB.


Asunto(s)
Antígeno AC133/biosíntesis , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Meduloblastoma/tratamiento farmacológico , Meduloblastoma/patología , Recurrencia Local de Neoplasia/patología , Células Madre Neoplásicas/patología , Factor de Transcripción STAT3/antagonistas & inhibidores , Antígeno AC133/inmunología , Animales , Neoplasias Encefálicas/inmunología , Línea Celular Tumoral , Proliferación Celular/fisiología , Femenino , Xenoinjertos , Humanos , Masculino , Meduloblastoma/inmunología , Ratones , Recurrencia Local de Neoplasia/inmunología , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Bibliotecas de Moléculas Pequeñas/farmacología , Regulación hacia Arriba
8.
Sci Rep ; 6: 27100, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27250534

RESUMEN

The molecular control of cell fate and behaviour is a central theme in biology. Inherent heterogeneity within cell populations requires that control of cell fate is studied at the single-cell level. Time-lapse imaging and single-cell tracking are powerful technologies for acquiring cell lifetime data, allowing quantification of how cell-intrinsic and extrinsic factors control single-cell fates over time. However, cell lifetime data contain complex features. Competing cell fates, censoring, and the possible inter-dependence of competing fates, currently present challenges to modelling cell lifetime data. Thus far such features are largely ignored, resulting in loss of data and introducing a source of bias. Here we show that competing risks and concordance statistics, previously applied to clinical data and the study of genetic influences on life events in twins, respectively, can be used to quantify intrinsic and extrinsic control of single-cell fates. Using these statistics we demonstrate that 1) breast cancer cell fate after chemotherapy is dependent on p53 genotype; 2) granulocyte macrophage progenitors and their differentiated progeny have concordant fates; and 3) cytokines promote self-renewal of cardiac mesenchymal stem cells by symmetric divisions. Therefore, competing risks and concordance statistics provide a robust and unbiased approach for evaluating hypotheses at the single-cell level.


Asunto(s)
Neoplasias de la Mama/genética , Linaje de la Célula/genética , Rastreo Celular/estadística & datos numéricos , Regulación Neoplásica de la Expresión Génica , Análisis de la Célula Individual/estadística & datos numéricos , Proteína p53 Supresora de Tumor/genética , Animales , Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Muerte Celular/efectos de los fármacos , Diferenciación Celular , División Celular/efectos de los fármacos , Línea Celular Tumoral , Rastreo Celular/métodos , Citocinas/farmacología , Doxorrubicina/farmacología , Femenino , Genotipo , Células Progenitoras de Granulocitos y Macrófagos/citología , Células Progenitoras de Granulocitos y Macrófagos/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Análisis de la Célula Individual/métodos , Imagen de Lapso de Tiempo
9.
Oncogenesis ; 5: e208, 2016 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-26999717

RESUMEN

Triple-negative breast cancers (TNBCs) represent a subset of breast tumors that are highly aggressive and metastatic, and are responsible for a disproportionate number of breast cancer-related deaths. Several studies have postulated a role for the epithelial-to-mesenchymal transition (EMT) program in the increased aggressiveness and metastatic propensity of TNBCs. Although EMT is essential for early vertebrate development and wound healing, it is frequently co-opted by cancer cells during tumorigenesis. One prominent signaling pathway involved in EMT is the transforming growth factor-ß (TGFß) pathway. In this study, we report that the novel POZ-ZF transcription factor Kaiso is highly expressed in TNBCs and correlates with a shorter metastasis-free survival. Notably, Kaiso expression is induced by the TGFß pathway and silencing Kaiso expression in the highly invasive breast cancer cell lines, MDA-MB-231 (hereafter MDA-231) and Hs578T, attenuated the expression of several EMT-associated proteins (Vimentin, Slug and ZEB1), abrogated TGFß signaling and TGFß-dependent EMT. Moreover, Kaiso depletion attenuated the metastasis of TNBC cells (MDA-231 and Hs578T) in a mouse model. Although high Kaiso and high TGFßR1 expression is associated with poor overall survival in breast cancer patients, overexpression of a kinase-active TGFßR1 in the Kaiso-depleted cells was insufficient to restore the metastatic potential of these cells, suggesting that Kaiso is a key downstream component of TGFß-mediated pro-metastatic responses. Collectively, these findings suggest a critical role for Kaiso in TGFß signaling and the metastasis of TNBCs.

10.
Oncogene ; 34(15): 2003-10, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-24909172

RESUMEN

Significant left-right (L-R) differences in tumor incidence and disease outcome occur for cancers of paired organs, including the breasts; however, the basis for this laterality is unknown. Here, we show that despite their morphologic symmetry, left versus right mammary glands in wild-type mice have baseline differences in gene expression that are L-R independently regulated during pubertal development, including genes that regulate luminal progenitor cell renewal, luminal cell differentiation, mammary tumorigenesis, tamoxifen sensitivity and chemotherapeutic resistance. In MMTV-cNeu(Tg/Tg) mice, which model HER2/Neu-amplified breast cancer, baseline L-R differences in mammary gene expression are amplified, sustained or inverted in a gene-specific manner and the mammary ductal epithelium undergoes L-R asymmetric growth and patterning. Comparative genomic analysis of mouse L-R mammary gene expression profiles with gene expression profiles of human breast tumors revealed significant linkage between right-sided gene expression and decreased breast cancer patient survival. Collectively, these findings are the first to demonstrate that mammary glands are lateralized organs, and, moreover, that mammary glands have L-R differential susceptibility to HER2/Neu oncogene-mediated effects on ductal epithelial growth and differentiation. We propose that intrinsic molecular laterality may have a role in L-R asymmetric breast tumor incidence and, furthermore, that interplay between the L-R molecular landscape and oncogene activity may contribute to the differential disease progression and patient outcome that are associated with tumor situs.


Asunto(s)
Glándulas Mamarias Animales/crecimiento & desarrollo , Neoplasias Mamarias Experimentales/patología , Animales , Neoplasias de la Mama/patología , Transformación Celular Neoplásica , Femenino , Expresión Génica , Humanos , Glándulas Mamarias Animales/metabolismo , Glándulas Mamarias Animales/patología , Glándulas Mamarias Humanas/crecimiento & desarrollo , Glándulas Mamarias Humanas/metabolismo , Glándulas Mamarias Humanas/patología , Ratones , Transducción de Señal
11.
Spine (Phila Pa 1976) ; 22(1): 44-50, 1997 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-9122781

RESUMEN

STUDY DESIGN: A prospective, functional assessment based on physical ability and independence in daily activities was performed of patients who had severe physical handicaps and spinal deformities and were undergoing scoliosis surgery. OBJECTIVES: To determine whether improving spinal alignment and truncal balance improved the functional abilities of handicapped patients. SUMMARY OF BACKGROUND DATA: Loss of truncal stability compromises the physical independence of children who are severely handicapped. Physiologic function also may be compromised. It is not clear whether improving truncal balance actually improves their level of independence or merely halts further deterioration. METHODS: Twenty patients with significant physical handicaps resulting from neuromuscular disorders or multiple congenital anomalies and significant spinal deformity and truncal imbalance were treated surgically to realign and stabilize their spines. Their level of physical independence was evaluated before surgery, including their ability to sit, ambulate, and complete activities of daily living. Evaluation was done before surgery, 6 months after surgery, and 12 months after surgery. A subjective assessment of cosmesis also was made. RESULTS: Corrective spinal surgery resulted in a deterioration of physical ability for the first 6 months. Most patients subsequently returned to their preoperative level of function. An improvement of function exceeding their preoperative level was not seen after 12 months. The cosmetic results of surgery were excellent. CONCLUSIONS: Corrective spinal surgery in patients with severe physical handicap should be performed early to preserve function and should not be dictated solely by the severity of the curvature. Improvement in the patient's level of independence may not necessarily occur after truncal stabilization. Cosmetic results in these patients with severe disabilities were extremely gratifying to the patients and their caregivers.


Asunto(s)
Personas con Discapacidad , Escoliosis/cirugía , Actividades Cotidianas , Adolescente , Niño , Preescolar , Personas con Discapacidad/psicología , Femenino , Humanos , Locomoción , Masculino , Salud Mental , Satisfacción del Paciente , Estudios Prospectivos , Escoliosis/etiología , Escoliosis/fisiopatología , Resultado del Tratamiento
12.
Addict Behav ; 12(4): 363-6, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3687519

RESUMEN

This paper reports a controlled evaluation of the six-part BBC TV series "So You Want To Stop Smoking?" which aimed to give advice and encouragement to smokers who wanted to stop. In an experimental design, 134 cigarette smokers in two firms were shown either the first two programs in the series or a control film of the same length. Smokers in the former group were asked to watch the remaining four programs at home on their own television sets. Questionnaires were sent to participants four months and one year later, and claims of abstinence were validated biochemically. The results did not provide clear evidence that the BBC series was more effective in encouraging smokers to try to stop and helping them to succeed than the control film. For comparison with our own results, we also abstract some findings from an uncontrolled but larger-scale evaluation conducted by the BBC's research department.


Asunto(s)
Educación en Salud , Fumar/terapia , Televisión , Adulto , Inglaterra , Femenino , Estudios de Seguimiento , Humanos , Masculino
13.
J Econ Entomol ; 94(5): 1177-82, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11681681

RESUMEN

A molecular method is presented for differentiating the morphologically cryptic leafminers Liriomyza langei Frick and L. huidobrensis (Blanchard). This method requires polymerase chain reaction (PCR) amplification of a 1031-bp region of mitochondrial cytochrome oxidase DNA followed by restriction fragment analysis using the restriction enzymes SpeI and EcoRV. Spel cuts the mitochondrial fragment of L. langei into two fragments, but does not cut the L. huidobrensis fragment. EcoRV cuts the L. huidobrensis fragment into two fragments, but does not cut the L. langei fragment. This PCR-restriction fragment-length polymorphism (RFLP) method is faster and less costly than DNA sequencing,which is currently the only other way to differentiate these two species. We apply the method to samples from recently introduced leafminer populations in Sri Lanka, Canada, and South Africa and find that the invasive leafminer in all three locations is L. huidobrensis.


Asunto(s)
Dípteros/clasificación , Animales , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Dípteros/genética , Complejo IV de Transporte de Electrones/genética , Mitocondrias/enzimología , Hojas de la Planta , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción
14.
BMJ ; 308(6930): 690-2, 1994 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-8142792

RESUMEN

OBJECTIVES: To assess the ease of use of suprapubic aspiration of urine under ultrasound guidance in babies with fever of uncertain cause and to assess the importance of bacterial counts and pyuria in relation to abnormalities of the urinary tract and the importance of pyuria in the absence of bacteriuria. DESIGN: Analysis of urine samples obtained by suprapubic aspiration in babies and children from July 1991 to June 1992. The clinical records of the children with bacteriuria and sterile pyuria were examined retrospectively. SETTING: Neonatal and paediatric wards of a district general hospital. SUBJECTS: 508 babies and children who had fever of uncertain cause or were seriously ill. RESULTS: No difficulties arose in the collection of 545 specimens. Bacteria were isolated from the specimens of 44 children, 24 of whom had abnormalities of the urinary tract. The bacterial count was < 10(8)/l in 18 of the children with bacteriuria, 10 of whom had abnormalities. No white cells were seen in 22 of the 46 bacteriuric specimens; nine of the children with no pyuria had vesicoureteric reflux. 439 of the 499 non-bacteriuric specimens showed no white cells. 60 children had pyuria without bacteriuria. CONCLUSIONS: The use of ultrasound guidance simplifies suprapubic aspiration of urine in babies. Low bacterial counts may be associated with abnormalities of the urinary tract. Laboratory techniques capable of detecting such counts reliably should be used. Pyuria is absent in half of babies and very young children with bacteriuria. It rarely occurs without bacteriuria, and if it does an explanation should be sought.


Asunto(s)
Fiebre de Origen Desconocido/orina , Succión/métodos , Orina , Bacteriuria/etiología , Preescolar , Recuento de Colonia Microbiana , Femenino , Fiebre de Origen Desconocido/etiología , Humanos , Lactante , Recién Nacido , Masculino , Piuria/etiología , Estudios Retrospectivos , Ultrasonografía Intervencional
15.
Oncogene ; 31(1): 93-103, 2012 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-21666715

RESUMEN

Human breast tumors comprise a minor sub-population of tumor-initiating cells (TICs), commonly termed cancer stem cells. TICs are thought to sustain tumor growth and to confer resistance to current anticancer therapies. Hence, targeting TIC may be essential to achieving durable cancer cures. To identify molecular targets in breast TIC, we employed a transgenic mouse model of ERBB2 breast cancer; tumors arising in this model comprise a very high frequency of TIC, which is maintained in tumor cell populations propagated in vitro as non-adherent tumorspheres. The Notch pathway is dysregulated in human breast tumors and overexpression of constitutively active Notch proteins induces mammary tumors in mice. The Notch pathway has also been implicated in stem cell processes including those of mammary epithelial stem cells. Hence, we investigated the potential that the Notch pathway is required for TIC activity. We found that an antagonist of Notch signaling, a gamma (γ)-secretase inhibitor termed MRK-003, inhibited the survival of tumorsphere-derived cells in vitro and eliminated TIC as assessed by cell transplantation into syngeneic mice. Whereas MRK-003 also inhibited the self-renewal and/or proliferation of mammosphere-resident cells, this effect of the inhibitor was reversible thus suggesting that it did not compromise the survival of these cells. MRK-003 administration to tumor-bearing mice eliminated tumor-resident TIC and resulted in rapid and durable tumor regression. MRK-003 inhibited the proliferation of tumor cells, and induced their apoptosis and differentiation. These findings suggest that MRK-003 targets breast TIC and illustrate that eradicating these cells in breast tumors ensures long-term, recurrence-free survival.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Óxidos S-Cíclicos/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Genes erbB-2 , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Tiadiazoles/uso terapéutico , Animales , Óxidos S-Cíclicos/farmacología , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Femenino , Perfilación de la Expresión Génica , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Transgénicos , Receptores Notch/fisiología , Tiadiazoles/farmacología
16.
AJNR Am J Neuroradiol ; 32(7): 1202-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21724574

RESUMEN

BACKGROUND AND PURPOSE: The surgical approach to parotid tumors is different for benign and malignant neoplasms, but the clinical symptoms do not correlate well with histology. Difficulties in tumor classification also arise in imaging modalities, in which sonography has the lowest and MR imaging, the highest accuracy. The purpose of this study was to review our experience using conventional MR imaging of the neck in the evaluation of parotid tumors and to evaluate which MR imaging findings are best able to predict malignant histology. MATERIALS AND METHODS: Eighty-four consecutive patients (43 males, 41 females; median age, 56 years; range, 9-85 years) with parotid gland tumors who underwent MR imaging before surgery were prospectively included in the present study and retrospectively analyzed. Histology was available for all tumors. We analyzed the following MR imaging parameters: signal intensity, contrast enhancement, lesion margins (well-defined versus ill-defined), lesion location (deep/superficial lobe), growth pattern (focal, multifocal, or diffuse), and extension into neighboring structures, perineural spread, and lymphadenopathy. RESULTS: The 57 (68%) benign and 27 (32%) malignant tumors consisted of 29 pleomorphic adenomas, 17 Warthin tumors, 11 various benign tumors, 5 mucoepidermoid carcinomas, 3 adenoid cystic carcinomas, 1 acinic cell carcinoma, 1 carcinoma ex pleomorphic adenoma, 9 metastases, and 8 various malignant neoplasms. Specific signs predictive of malignancy were the following: T2 hypointensity of the parotid tumor (P = .048), ill-defined margins (P = .001), diffuse growth (P = .012), infiltration of subcutaneous tissue (P = .0034), and lymphadenopathy (P = .012). CONCLUSIONS: Low signal intensity on T2-weighted images and postcontrast ill-defined margins of a parotid tumor are highly suggestive of malignancy.


Asunto(s)
Adenoma/patología , Imagen por Resonancia Magnética/métodos , Neoplasias/patología , Neoplasias de la Parótida/patología , Adenolinfoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Acinares/patología , Carcinoma Adenoide Quístico/patología , Carcinoma Mucoepidermoide/patología , Niño , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Adulto Joven
17.
Environ Entomol ; 39(1): 50-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20146839

RESUMEN

Soybean aphid (Aphis glycines Matsumura) is a severe pest of soybean in central North America. Outbreaks of the aphid in Ontario are often spotty in distribution, with some geographical areas affected severely and others with few or no aphid populations occurring in soybean for the duration of the season. A. glycines spend summers on soybean and overwinter on buckthorn, a shrub that is widespread in southern Ontario and is commonly found in agricultural hedgerows and at the margins of woodlots. A. glycines likely use both short distance migratory flights from buckthorn and longer distance dispersal flights in the search for acceptable summer hosts. This study aims to model colonization of soybean fields by A. glycines engaged in early-season migration from overwintering hosts. Akaike's information criterion (AIC) was used to rank numerous competing linear and probit models using field parameters to predict aphid presence, colonization, and density. The variable that best modeled aphid density in soybean fields in the early season was the ratio of buckthorn density to field area, although dramatic differences in relationships between the parameters were observed between study years. This study has important applications in predicting areas that are at elevated risk of developing economically damaging populations of soybean aphid and which may act as sources for further infestation.


Asunto(s)
Áfidos/fisiología , Glycine max/parasitología , Interacciones Huésped-Parásitos , Modelos Biológicos , Rhamnus/parasitología , Animales , Ambiente , Ontario , Densidad de Población
19.
Antimicrob Agents Chemother ; 51(3): 991-7, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17194834

RESUMEN

The artemisinin-based combination therapies artemether-lumefantrine (AL) and amodiaquine (AQ) plus artesunate have been adopted for treatment of Plasmodium falciparum malaria in many African countries. Molecular markers of parasite resistance suitable for surveillance have not been established for any of the component drugs in either of these combinations. We assessed P. falciparum mdr1 (Pfmdr1) alleles present in 300 Tanzanian children presenting with uncomplicated falciparum malaria, who were enrolled in a clinical trial of antimalarial therapy. Pfmdr1 genotype analysis was also performed with isolates from 182 children who failed AQ monotherapy and 54 children who failed AL treatment. Pfmdr1 alleles 86Y, 184Y, and 1246Y were more common among treatment failures in the AQ group than among pretreatment infections. The converse was found in the AL-treated group. Children presenting with the 86Y/184Y/1246Y Pfmdr1 haplotype and treated with AQ were significantly more likely to retain this haplotype if they were parasite positive during posttreatment follow-up than were children treated with AL (odds ratio, 33.25; 95% confidence interval, 4.17 to 1441; P, <0.001). We conclude that AL and AQ exert opposite within-host selective effects on the Pfmdr1 gene of P. falciparum.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Amodiaquina/farmacología , Antimaláricos/farmacología , Artemisininas/farmacología , Etanolaminas/farmacología , Fluorenos/farmacología , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Alelos , Animales , Arteméter , Preescolar , Resistencia a Medicamentos , Femenino , Ligamiento Genético/genética , Genotipo , Haplotipos , Humanos , Lactante , Lumefantrina , Malaria Falciparum/tratamiento farmacológico , Masculino , Polimorfismo Genético/genética , Polimorfismo de Nucleótido Simple/genética , Tanzanía , Resultado del Tratamiento
20.
Prev Med ; 15(3): 213-31, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3529076

RESUMEN

Growing interest has been expressed by the business community concerning intervention against smoking in the workplace. As most adult smokers are unlikely to have access to smokers' clinics or other treatment facilities outside the workplace, the workplace itself could be an ideal location for the provision of treatment programs. If the interest of the business community can be translated into action, large populations of smokers would become accessible to workplace treatment programs. Despite this possibility, the potential of the workplace for smoking intervention remains largely unexplored. In this review, the main reasons for workplace smoking intervention are discussed, and the available evidence for the main strategies (prohibition, incentives, treatment, and multicomponent) is reviewed and critically evaluated. The current emphasis in treatment studies is still on physician counseling, and the quality of reported work uneven. Many published studies not intended as evaluations, and many of those which are, have severe procedural or methodological flaws. The particular problems of evaluating workplace studies are discussed and the current research position is summarized. Because the number of evaluative studies is small, the recommendations that can be based on them are fairly limited. In conclusion, it is argued that a body of well-controlled evaluations is needed before the unique characteristics of the workplace can be assessed and exploited in smoking interventions.


Asunto(s)
Promoción de la Salud , Servicios de Salud del Trabajador , Prevención del Hábito de Fumar , Adulto , Humanos , Masculino , Persona de Mediana Edad , Relaciones Médico-Paciente , Riesgo , Automedicación , Grupos de Autoayuda
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