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1.
Sex Reprod Healthc ; 41: 100999, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38959679

RESUMEN

OBJECTIVE: The term 'vulnerable' is often used to describe women facing psychosocial adversity during pregnancy, implying a heightened risk of experiencing suboptimal pregnancy outcomes. While this label might facilitate the pathway to appropriate care, it can be perceived as stigmatizing by the women it intends to help, which could deter their interaction with healthcare services. This study explores how women facing psychosocial adversity before, during and after pregnancy perceive the concept of vulnerability and experience being labeled as such. METHODS: We conducted a thematic analysis of semi-structured, in-depth interviews. Through purposive sampling targeting maximum variation, ten women of diverse backgrounds were included. RESULTS: Three central themes emerged: defining vulnerability, embracing vulnerability and the feeling of being stigmatized. Women perceived vulnerability as an inability to adequately care for themselves or their children, necessitating additional support alongside routine antenatal care. Acceptance of the 'vulnerable' label came when it also acknowledged their proactive efforts and strengths to improve their situation. Conversely, if discussions surrounding vulnerability failed to recognize women's agency - specifically, their personal journeys and the courage needed to seek support - the label was perceived as stigmatizing. CONCLUSIONS: Addressing vulnerability effectively in maternity care requires a nuanced, patient-centered approach, acknowledging both the challenges and strengths of women facing psychosocial adversities. Emphasizing personal narratives and their courage in seeking support can mitigate the stigmatizing effects of the 'vulnerable' label. Integrating these narratives into maternal healthcare practices can foster deeper connections with the women involved, enhancing the overall quality of care.

2.
Eur J Cancer ; 171: 114-123, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35716537

RESUMEN

INTRODUCTION: In 1-3% of non-small cell lung cancer (NSCLC) human epidermal growth factor 2 (HER2) mutations are identified as a genomic driver. Nevertheless, no HER2-targeted treatment is approved for NSCLC. In the Drug Rediscovery Protocol (DRUP), patients are treated with off-label drugs based on their molecular profile. Here, we present the results of the cohort 'trastuzumab/pertuzumab for HER2 exon20 mutation positive (HER2m+) NSCLC'. METHODS: Patients with treatment refractory, advanced HER2m+ NSCLC with measurable disease (RECISTv1.1) were eligible. Treatment with intravenous trastuzumab combined with pertuzumab every 3 weeks was administered. The primary end-point was clinical benefit (CB: either objective response or stable disease ≥ 16 weeks). Patients were enrolled using a Simon-like 2-stage design, with 8 patients in stage 1 and up to 24 patients in stage 2 if at least 1 patient had CB in stage 1. At baseline, a biopsy for biomarker analysis, including whole genome sequencing, was obtained. RESULTS: Twenty-four evaluable patients were enrolled and treated between May 2017 and August 2020. CB was observed in 9 patients (38%); including an objective response rate of 8.3% (2 patients had a partial response) and 7 patients with stable disease ≥ 16 weeks. The most frequently observed HER2 mutation was p.Y772_A775dup (71%, n = 20). Median follow-up was 13 months, median progression-free survival and overall survival 4 (95% CI 3-6) and 10 months (95% CI 4 - not reached), respectively. Whole genome sequencing data (available for 67% of patients) confirmed the inclusion mutation in all cases. No unexpected toxicity was observed. CONCLUSION: Despite the fact that the study did meet its primary end-point, trastuzumab/pertuzumab was only marginally active in a subset of patients with heavily pre-treated HER2m+ NSCLC.


Asunto(s)
Neoplasias de la Mama , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Exones , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapéutico
3.
Virchows Arch ; 480(3): 693-697, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34142226

RESUMEN

Mucosal melanomas are rare and only a small portion bear BRAF mutations while cutaneous melanomas have a much higher prevalence and often harbor BRAF mutations. We present two cases in which, after a malignant melanocytic mucosal lesion with a BRAF mutation was found, the primary cutaneous source was identified and clonality confirmed between the lesions. In both cases, primary lesions occurred on the scalp, an often-overlooked site. Both lesions showed signs of regression implying that in due time these lesions could have been fully regressed and might never have been detected. In that case, the metastatic mucosal lesion would erroneously be identified as a BRAF-mutated mucosal melanoma. These cases give warrant; a careful dermatological inspection should be instigated when confronted with a BRAF-mutated mucosal melanoma. We hypothesize that some BRAF-mutated mucosal melanomas might actually represent metastases of regressed cutaneous melanomas.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/genética , Melanoma/patología , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Cuero Cabelludo/patología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología
4.
Virchows Arch ; 479(1): 195-202, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33040161

RESUMEN

The molecular background of a significant proportion of spitzoid neoplasms is still unknown. Recently, activating mutations in MAP2K1 have been described in a few spitzoid lesions, but not in benign Spitz nevi. We report four cases of melanocytic tumors with spitzoid features in which a MAP2K1 mutation was detected. The lesions did not show a single distinct phenotype and ranged from benign to malignant. Two cases resembled desmoplastic Spitz nevi. Based on the combination of morphological, immunohistochemical, and molecular findings, one case was classified as benign, one as probably benign, possibly intermediate low-grade (MELTUMP-melanocytic tumor of unknown malignant potential), one case was classified as intermediate (MELTUMP), and one case was considered a superficial spreading melanoma with spitzoid features. Based on this, we conclude that MAP2K1 mutations can indicate a spitzoid genetic signature and can be found in both benign and malignant spitzoid neoplasms.


Asunto(s)
Biomarcadores de Tumor/genética , MAP Quinasa Quinasa 1/genética , Melanoma/genética , Mutación , Nevo de Células Epitelioides y Fusiformes/genética , Neoplasias Cutáneas/genética , Adolescente , Anciano , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Melanoma/enzimología , Melanoma/patología , Persona de Mediana Edad , Nevo de Células Epitelioides y Fusiformes/enzimología , Nevo de Células Epitelioides y Fusiformes/patología , Fenotipo , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/patología
5.
Med Vet Entomol ; 35(1): 134-140, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32648329

RESUMEN

Many previous studies have shown a great phylogenetic and biological variability of Trypanosoma cruzi using different molecular and biochemical methods. Populations of T. cruzi were initially clustered into two main lineages called TcI and TcII by the size of the mini-exon PCR product. In the present study, 33 isolates derived from three triatomine taxa, which belong to the Triatoma brasiliensis species complex (Triatoma juazeirensis, Triatoma melanica and Triatoma sherlocki); collected in three distinct areas of Bahia state were characterized by PCR. The isolates were identified by the size of the mini-exon gene, 18S rRNA and 24Sα rRNA amplicons. T. cruzi isolates obtained in sylvatic and intradomiciliar ecotopes, derived from T. juazeirensis and T. melanica, were identified as TcI while the parasites originated from T. sherlocki were characterized as TcI and TcII genotypes, respectively. Those species are present in sylvatic ecotopes but are able to infest intradomiciliar areas. Therefore, it would be important to maintain studies in those localities of Bahia and further investigate the possibilities of Chagas disease transmission. Human disease may occur by any T. cruzi genotype and not only by TcII as it is the case in Amazonia.


Asunto(s)
Genotipo , Triatoma/parasitología , Trypanosoma cruzi/genética , Animales , Brasil , Exones , Genes Protozoarios , ARN Protozoario/análisis , ARN Ribosómico 18S/análisis , Especificidad de la Especie , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/aislamiento & purificación
7.
Ann Oncol ; 28(1): 96-102, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27742654

RESUMEN

Background: Mismatch repair (MMR)-deficiency analysis is increasingly recommended for all endometrial cancers, as it identifies Lynch syndrome patients, and is emerging as a prognostic classifier to guide adjuvant treatment. The aim of this study was to define the optimal approach for MMR-deficiency testing and to clarify discrepancies between microsatellite instability (MSI) analysis and immunohistochemical (IHC) analysis of MMR protein expression. Patients and methods: Six hundred ninety- six endometrial cancers were analyzed for MSI (pentaplex panel) and MMR protein expression (IHC). Agreement between methodologies was calculated using Cohen's Kappa. MLH1 promoter hypermethylation, dinucleotide microsatellite markers and somatic MMR and POLE exonuclease domain (EDM) gene variants (using next-generation/Sanger sequencing) were analyzed in discordant cases. Results: MSI was found in 180 patients. Complete loss of expression of one or more MMR proteins was observed in 196 cases. A PMS2- and MSH6-antibody panel detected all cases with loss of MMR protein expression. The results of MSI and MMR protein expression were concordant in 655/696 cases (kappa = 0.854, P < 0.001). Ambiguous cases (n = 41, 6%) included: subclonal loss of MMR protein expression (n = 18), microsatellite stable or MSI-low cases with loss of MMR protein expression (n = 20), and MSI-low or MSI-high cases with retained MMR protein expression (n = 3). Most of these cases could be explained by MLH1 promoter hypermethylation. Five of seven cases with solitary loss of PMS2 or MSH6 protein expression carried somatic gene variants. Two MSI-high cases with retained MMR protein expression carried a POLE-EDM variant. Conclusion: MSI and IHC analysis are highly concordant in endometrial cancer. This holds true for cases with subclonal loss of MMR protein expression. Discordant MMR-proficient/MSI-high cases (<1%), may be explained by POLE-EDM variants.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Colorrectales/diagnóstico , Reparación de la Incompatibilidad de ADN/genética , Neoplasias Endometriales/genética , Inestabilidad de Microsatélites , Síndromes Neoplásicos Hereditarios/diagnóstico , Neoplasias Encefálicas/complicaciones , Neoplasias Colorrectales/complicaciones , Femenino , Humanos , Inmunohistoquímica , Síndromes Neoplásicos Hereditarios/complicaciones , Reacción en Cadena de la Polimerasa
8.
Oncogenesis ; 5: e222, 2016 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-27159675

RESUMEN

Chondrosarcomas are malignant cartilage-forming bone tumors, which are intrinsically resistant to chemo- and radiotherapy, leaving surgical removal as the only curative treatment option. Therefore, our aim was to identify genes involved in chondrosarcoma cell survival that could serve as a target for therapy. siRNA screening for 51 apoptosis-related genes in JJ012 chondrosarcoma cells identified BIRC5, encoding survivin, as essential for chondrosarcoma survival. Using immunohistochemistry, nuclear as well as cytoplasmic survivin expression was analyzed in 207 chondrosarcomas of different subtypes. Nuclear survivin has been implicated in cell-cycle regulation while cytoplasmic localization is important for its anti-apoptotic function. RT-PCR was performed to determine expression of the most common survivin isoforms. Sensitivity to YM155, a survivin inhibitor currently in phase I/II clinical trial for other tumors, was examined in 10 chondrosarcoma cell lines using viability assay, apoptosis assay and cell-cycle analysis. Survivin expression was found in all chondrosarcoma patient samples. Higher expression of nuclear and cytoplasmic survivin was observed with increasing histological grade in central chondrosarcomas. Inhibition of survivin using YM155 showed that especially TP53 mutant cell lines were sensitive, but no caspase 3/7 or PARP cleavage was observed. Rather, YM155 treatment resulted in a block in S phase in two out of three chondrosarcoma cell lines, indicating that survivin is more involved in cell-cycle regulation than in apoptosis. Thus, survivin is important for chondrosarcoma survival and chondrosarcoma patients might benefit from survivin inhibition using YM155, for which TP53 mutational status can serve as a predictive biomarker.

9.
Virchows Arch ; 465(6): 703-13, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25304290

RESUMEN

Giant cell tumor of bone (GCTB) displays worrisome clinical features such as local recurrence and occasionally metastatic disease which are unpredictable by morphology. Additional routinely usable biomarkers do not exist. Gene expression profiles of six clinically defined groups of GCTB and one group of aneurysmal bone cyst (ABC) were determined by microarray (n = 33). The most promising differentially expressed genes were validated by Q-PCR as potential biomarkers in a larger patient group (n = 41). Corresponding protein expression was confirmed by immunohistochemistry. Unsupervised hierarchical clustering reveals a metastatic GCTB cluster, a heterogeneous, non-metastatic GCTB cluster, and a primary ABC cluster. Balanced score testing indicates that lumican (LUM) and decorin (DCN) are the most promising biomarkers as they have lower level of expression in the metastatic group. Expression of dermatopontin (DPT) was significantly lower in recurrent tumors. Validation of the results was performed by paired and unpaired t test in primary GCTB and corresponding metastases, which proved that the differential expression of LUM and DCN is tumor specific rather than location specific. Our findings show that several genes related to extracellular matrix integrity (LUM, DCN, and DPT) are differentially expressed and may serve as biomarkers for metastatic and recurrent GCTB.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Óseas/genética , Decorina/biosíntesis , Tumor Óseo de Células Gigantes/genética , Neoplasias Pulmonares/secundario , Adolescente , Adulto , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Niño , Proteoglicanos Tipo Condroitín Sulfato/biosíntesis , Proteoglicanos Tipo Condroitín Sulfato/genética , Análisis por Conglomerados , Decorina/genética , Regulación hacia Abajo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Proteínas de la Matriz Extracelular/biosíntesis , Proteínas de la Matriz Extracelular/genética , Femenino , Perfilación de la Expresión Génica , Tumor Óseo de Células Gigantes/metabolismo , Tumor Óseo de Células Gigantes/patología , Humanos , Inmunohistoquímica , Sulfato de Queratano/biosíntesis , Sulfato de Queratano/genética , Lumican , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcriptoma , Adulto Joven
10.
Ann Oncol ; 25(8): 1500-5, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24962703

RESUMEN

Teenagers and young adults (TYA) cancer contributes substantially to morbidity and mortality in a population with much to offer society. TYA place distinct challenges upon cancer care services, many reporting feeling marginalized and their needs not being met in adult or paediatric cancer services. Bone tumours such as osteosarcoma and Ewing sarcoma, because of their age at presentation and the complexity of their care, are where challenges in managing (TYA) with cancer have often been most readily apparent. Bone sarcomas may be managed by paediatric or medical oncologists, and require fastidious attention to protocol. A lack of recent improvement in survival in TYA with bone tumours may be linked to a lack of specialist care, poor concordance with therapy in some situations and TYA-specific pharmacology. Participation in clinical trials, particularly of young adults, is low, hindering progress. All these requirements may be best met by a concerted effort to create collaborative care between adult and paediatric experts in bone sarcoma, working together to meet TYA patients' needs.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Adolescente , Adulto , Edad de Inicio , Neoplasias Óseas/epidemiología , Neoplasias Óseas/terapia , Consenso , Humanos , Osteosarcoma/epidemiología , Osteosarcoma/terapia , Sarcoma de Ewing/epidemiología , Sarcoma de Ewing/terapia , Adulto Joven
11.
Br J Cancer ; 109(8): 2142-54, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24064975

RESUMEN

BACKGROUND: Osteosarcoma (OS) is the most common bone tumour in children and adolescents. Despite aggressive therapy regimens, treatment outcomes are unsatisfactory. Targeted delivery of drugs can provide higher effective doses at the site of the tumour, ultimately improving the efficacy of existing therapy. Identification of suitable receptors for drug targeting is an essential step in the design of targeted therapy for OS. METHODS: We conducted a comparative analysis of the surface proteome of human OS cells and osteoblasts using cell surface biotinylation combined with nano-liquid chromatography - tandem mass spectrometry-based proteomics to identify surface proteins specifically upregulated on OS cells. This approach generated an extensive data set from which we selected a candidate to study for its suitability as receptor for targeted treatment delivery to OS. First, surface expression of the ephrin type-A receptor 2 (EPHA2) receptor was confirmed using FACS analysis. Ephrin type-A receptor 2 expression in human tumour tissue was tested using immunohistochemistry. Receptor targeting and internalisation studies were conducted to assess intracellular uptake of targeted modalities via EPHA2. Finally, tissue micro arrays containing cores of human OS tissue were stained using immunohistochemistry and EPHA2 staining was correlated to clinical outcome measures. RESULTS: Using mass spectrometry, a total of 2841 proteins were identified of which 156 were surface proteins significantly upregulated on OS cells compared with human primary osteoblasts. Ephrin type-A receptor 2 was highly upregulated and the most abundant surface protein on OS cells. In addition, EPHA2 was expressed in a vast majority of human OS samples. Ephrin type-A receptor 2 effectively mediates internalisation of targeted adenoviral vectors into OS cells. Patients with EPHA2-positive tumours showed a trend toward inferior overall survival. CONCLUSION: The results presented here suggest that the EPHA2 receptor can be considered an attractive candidate receptor for targeted delivery of therapeutics to OS.


Asunto(s)
Neoplasias Óseas/metabolismo , Osteosarcoma/metabolismo , Receptor EphA2/análisis , Receptor EphA2/metabolismo , Neoplasias Óseas/química , Neoplasias Óseas/tratamiento farmacológico , Línea Celular Tumoral , Cromatografía Liquida/métodos , Minería de Datos , Femenino , Citometría de Flujo/métodos , Humanos , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Terapia Molecular Dirigida , Osteosarcoma/química , Osteosarcoma/tratamiento farmacológico , Pronóstico , Proteoma/análisis , Proteoma/metabolismo , Proteómica/métodos , Espectrometría de Masas en Tándem/métodos , Regulación hacia Arriba
12.
Neth Heart J ; 2012 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-22314614

RESUMEN

BACKGROUND: It is important to gain insight into opportunities for secondary prevention of cardiovascular disease. Our aim was to investigate levels and trends in cardiovascular risk factors and drug treatment in Dutch post-myocardial infarction (MI) patients between 2002 and 2006 and to make comparisons with the EUROASPIRE surveys (1999-2007). METHODS: We analysed data from 4837 post-MI patients (aged 69 years, 78% men) from 32 Dutch hospitals, using baseline cross-sectional data from the Alpha Omega Trial. RESULTS: Between 2002 and 2006, significant declines were found in the prevalence of smoking (23% to 16%, p < 0.001), hypercholesterolaemia (≥5 mmol/l; 54% to 27%, p < 0.0001) and hypertension (≥140/90 mmHg; 58% to 48%, p < 0.001). The prevalence of antithrombotic drugs was high (97%). The prevalence of lipid-modifying drugs and antihypertensives was high, and increased (74% to 90%, p < 0.0001 and 82% to 93%, p < 0.001, respectively). The prevalence of obesity (27%) was high in 2002 and decreased to 24% in 2006, albeit not significantly. Diabetes prevalence was high and increased between 2002 and 2006 (18% to 22%, p = 0.02). In comparison with EUROASPIRE patients, who were on average 8-10 years younger, our study in 2006 included patients with lower levels of obesity, hypertension, hypercholesterolaemia, diabetes and lower use of antiplatelets and ß-blockers, but similar levels of lipid-modifying drugs. CONCLUSIONS: This study showed that older Dutch post-MI patients were adequately treated with drugs, and that risk factors reached lower levels than in the younger EUROASPIRE patients. However, there is room for improvement in diet and lifestyle, given the high prevalence of smoking, obesity, and diabetes.

13.
Ann Oncol ; 23(6): 1617-26, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22112972

RESUMEN

BACKGROUND: Chondrosarcomas are malignant cartilage-forming tumors notorious for their resistance to conventional chemo- and radiotherapy. Postulated explanations describe the inaccessibility due to abundant hyaline cartilaginous matrix, presence of multidrug resistance (MDR) pumps, and expression of anti-apoptotic BCL-2 family members. MATERIALS AND METHODS: We studied the sensitivity of chondrosarcoma cell lines (SW1353, CH2879, JJ012, OUMS27) and two primary cultures for doxorubicin and cisplatin. We examined the role of extracellular matrix using three-dimensional (3D) pellet models and MDR pump activity using fluorescence-activated cell sorter analysis. The role of BCL-2 family members was investigated using the BH3 mimetic ABT-737. RESULTS: Chondrosarcoma cells showed highest resistance to cisplatin. 3D cell pellets, morphologically strongly resembling chondrosarcoma in vivo, confirmed nuclear incorporation of doxorubicin. MDR pump activity was heterogeneous among cultures. Chondrosarcoma cells responded to ABT-737 and combination with doxorubicin led to complete loss of cell viability and apoptosis with cytochrome C release. CONCLUSIONS: Despite MDR pump activity and abundance of hyaline cartilaginous matrix, doxorubicin is able to accumulate in the cell nuclei. By repairing the apoptotic machinery, we were able to sensitize chondrosarcoma cells to doxorubicin and cisplatin, indicating an important role for BCL-2 family members in chemoresistance and a promising new treatment strategy for inoperable chondrosarcoma.


Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Doxorrubicina/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína bcl-X/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/metabolismo , Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/farmacología , Técnicas de Cultivo de Célula , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Condrosarcoma , Relación Dosis-Respuesta a Droga , Doxorrubicina/metabolismo , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Expresión Génica , Células HL-60 , Humanos , Concentración 50 Inhibidora , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Proteínas de Neoplasias/metabolismo , Nitrofenoles/farmacología , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/genética , Sulfonamidas/farmacología , Proteína bcl-X/genética
14.
Trans R Soc Trop Med Hyg ; 105(7): 380-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21600622

RESUMEN

We examined by parasitological tests (hemocultures and buffy coat) infection by Trypanosoma cruzi and T. evansi in blood samples from Leopardus pardalis, Cerdocyon thous and domestic dogs. Besides, 25 T. cruzi isolates previously derived from feral pigs and small wild mammals were here characterized by miniexon gene and demonstrated to be in the TcI genotype. Herein, we make an overall analysis of the transmission cycle of both trypanosome species in the light of the assemblage of data collected over the last seven years. The carnivore Nasua nasua was confirmed to play a major role in the transmission cycles of both T. cruzi and T. evansi since it was the species that had the higher prevalence and higher parasitemias by both flagellate species. In addition, our results show that both trypanosomatid species may be found throughout the Pantanal landscape, in all forest strata, as shown by the infection of carnivore, arboreal and terrestrial scansorial marsupial species in complex and seasonal transmission cycles. We propose that transmission of T. cruzi and T. evansi in the southern Pantanal region takes place via an intricate ecological trophic network involving generalist and specialist mammal species that are linked through a robust food-web connection.


Asunto(s)
Cadena Alimentaria , Tripanosomiasis/veterinaria , Animales , Animales Salvajes/parasitología , Anticuerpos Antiprotozoarios/análisis , Capa Leucocitaria de la Sangre , Brasil/epidemiología , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/veterinaria , Reservorios de Enfermedades , Perros/parasitología , Felidae/parasitología , Técnica del Anticuerpo Fluorescente Directa/veterinaria , Zorros/parasitología , Trypanosoma , Trypanosoma cruzi , Tripanosomiasis/transmisión
15.
Clin Genet ; 79(3): 207-18, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21114486

RESUMEN

Previous studies on the counsellees' perception of DNA test results did not clarify whether counsellees were asked about their recollections or interpretations, and focused only on patients' own risks and not on the likelihood that cancer is heritable in the family. We tested differences and correlations of four perception aspects: recollections and interpretations of both cancer risks and heredity likelihood. In a retrospective study, women tested for BRCA1/2 on average, 5 years ago, completed questionnaires about their perception. Participants had received an unclassified variant (n = 76), uninformative (n = 76) or pathogenic mutation (n = 51) result in BRCA1/2. Analyses included t-tests, correlations and structural equation modelling. The counsellees' perception showed to consist of four distinctive phenomena: recollections and interpretations of cancer risks and of heredity likelihood. This distinctiveness was suggested by significant differences between these perception variables. Moderate to strong correlations were found between these variables, suggesting that these differences between variables were consistent. The relationships between these variables were not influenced by actually communicated DNA test results, sociodemographics, medical and pedigree information, or framing of cancer risk questions. The largest differences between recollections and interpretations were found in the unclassified variant group and the smallest in uninformatives. Cancer risks and heredity likelihood correlated least in the pathogenic mutation group. Communication of ambiguous genetic information enlarged the differences. To understand the counsellees' perception of genetic counselling, researchers should study recollections and interpretations of cancer risks and heredity likelihood. Genetic counsellors should explicitly address the counsellees' recollections and interpretations, and be aware of possible inaccuracies.


Asunto(s)
Neoplasias de la Mama , Asesoramiento Genético , Pruebas Genéticas/estadística & datos numéricos , Recuerdo Mental , Neoplasias Ováricas , Percepción , Riesgo , Neoplasias de la Mama/genética , Neoplasias de la Mama/psicología , Femenino , Genes BRCA1 , Genes BRCA2 , Humanos , Persona de Mediana Edad , Modelos Teóricos , Neoplasias Ováricas/genética , Neoplasias Ováricas/psicología , Estudios Retrospectivos , Encuestas y Cuestionarios
16.
Exp Parasitol ; 127(1): 308-12, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20655911

RESUMEN

Chagas disease is an enzootic disease, in which the flagellate Trypanosoma cruzi infects a large variety of animals. Humans are accidentally infected due to the migration into wild environments. To identify T. cruzi discrete typing units (DTUs), 19 Brazilian isolates from different biomes and hosts were analyzed by PCR amplification of 24Sα rRNA, 18S rRNA and mini-exon gene sequences. The majority of the isolates was classified as TcIIb (TcII) but subtypes TcIIc (TcIII) and TcIId (TcV) were also identified. In addition, in monkeys TcI was detected.


Asunto(s)
Enfermedad de Chagas/parasitología , Trypanosoma cruzi/clasificación , Animales , Brasil , Didelphis/parasitología , Exones/genética , Genotipo , Humanos , Leontopithecus/parasitología , Reacción en Cadena de la Polimerasa , Enfermedades de los Primates/parasitología , Primates , ARN Ribosómico/genética , Enfermedades de los Roedores/parasitología , Roedores , Triatominae/parasitología , Trypanosoma cruzi/genética
18.
Br J Cancer ; 101(11): 1909-18, 2009 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-19888226

RESUMEN

BACKGROUND: Osteosarcoma is the most prevalent primary malignant bone tumour in children and young adults, with poor survival in 40% of patients. To identify the signalling pathways involved in tumourigenesis, we compared gene expression in osteosarcoma with that in its presumed normal counterparts. METHODS: Genome-wide expression profiles were generated from 25 high-grade central osteosarcoma prechemotherapy biopsies, 5 osteoblastomas, 5 mesenchymal stem cell (MSC) populations and these same MSCs differentiated into osteoblasts. Genes that were differentially expressed were analysed in the context of the pathways in which they function using the GenMAPP programme. RESULTS: MSCs, osteoblasts, osteoblastomas and osteosarcomas clustered separately and thousands of differentially expressed genes were identified. The most significantly altered pathways are involved in cell cycle regulation and DNA replication. Several upstream components of the Wnt signalling pathway are downregulated in osteosarcoma. Two genes involved in degradation of beta-catenin protein, the key effectors of Wnt signalling, Axin and GSK3-beta, show decreased expression, suggesting that Wnt signalling is no longer under the control of regular signals. Comparing benign osteoblastomas with osteosarcomas identified cell cycle regulation as the most prominently changed pathway. CONCLUSION: These results show that upregulation of the cell cycle and downregulation of Wnt signalling have an important role in osteosarcoma genesis. Gene expression differences between highly malignant osteosarcoma and benign osteoblastoma involve cell cycle regulation.


Asunto(s)
Neoplasias Óseas/patología , Células Madre Mesenquimatosas/patología , Células Madre Neoplásicas/patología , Osteosarcoma/patología , Adolescente , Adulto , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Ciclo Celular/fisiología , Diferenciación Celular , Línea Celular Tumoral , Niño , Preescolar , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Células Madre Mesenquimatosas/metabolismo , Células Madre Neoplásicas/metabolismo , Osteoblastoma/genética , Osteoblastoma/metabolismo , Osteoblastoma/patología , Osteosarcoma/genética , Osteosarcoma/metabolismo , Transducción de Señal , Regulación hacia Arriba , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Adulto Joven
19.
Acta Trop ; 111(2): 102-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19467452

RESUMEN

Determining the reservoir hosts for parasites is crucial for designing control measures, but it is often difficult to identify the role that each host species plays in maintaining the cycle of infection in the wild. One way to identify potential maintenance hosts is to estimate key parameters associated with transmission and pathogenicity. Here we assess the potential for three native rodent species of the Brazilian Pantanal (Clyomys laticeps, Thrichomys pachyurus and Oecomys mamorae) to act as reservoir or maintenance hosts of Trypanosoma evansi, an important parasite of domestic livestock. By analyzing blood parameters of naturally infected wild-caught rodents of these species, we compared their levels of parasitemia and anemia due to T. evansi infection with literature values for other host species infected by this parasite. We also analyzed levels of these blood parameters relative to infection by Trypanosoma cruzi, the causative agent of Chagas disease in humans, for which wild rodents are already thought to be important reservoir species. All three species showed low impacts of the two trypanosomes on their blood parameters compared to other species, suggesting that they experience a low virulence of trypanosome infection under natural conditions in the Pantanal and might act as maintenance hosts of trypanosome infections. The low parasitemia of trypanosome infections suggests that these rodents play a secondary role in the transmission cycle compared to other species, especially compared to the capybara (Hydrochaeris hydrochaeris) which also experiences low pathogenicity due to infection despite much higher levels of parasitemia.


Asunto(s)
Reservorios de Enfermedades/parasitología , Roedores/parasitología , Trypanosoma/aislamiento & purificación , Tripanosomiasis/transmisión , Anemia , Animales , Sangre/parasitología , Brasil/epidemiología , Parasitemia
20.
Parasitology ; 135(9): 1093-100, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18620619

RESUMEN

Protease expression among TCI and TCII field isolates was analysed. Gelatin-containing gels revealed hydrolysis bands with molecular masses ranging from 45 to 66 kDa. The general protease expression profile showed that TCII isolates presented higher heterogeneity compared to TCI. By utilizing protease inhibitors, we showed that all active proteases at acid pH are cysteine-proteases and all proteases active at alkaline pH are metalloproteases. However, the expression of cruzipain, the T. cruzi major cysteine-protease, did not reproduce a heterogeneous TCII cysteine zymogram profile. Dendogram analyses based on presence/absence matrices of proteases and cruzipain bands showed a TCI separation from the TCII group with 50-60% similarity. We suggest that the observed cysteine protease diversification contributes to differential host infection between TCI and II genotypes.


Asunto(s)
Cisteína Endopeptidasas/genética , Péptido Hidrolasas/genética , Trypanosoma cruzi/enzimología , Animales , Western Blotting , Cisteína Endopeptidasas/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Genotipo , Interacciones Huésped-Parásitos/genética , Filogenia , Inhibidores de Proteasas/farmacología , Proteínas Protozoarias , Trypanosoma cruzi/genética
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