Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 247
Filtrar
Más filtros

Intervalo de año de publicación
1.
Pharmacogenet Genomics ; 34(4): 91-104, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38682317

RESUMEN

OBJECTIVES: This study explored the association of deleterious variants in pharmacodynamics (PD) genes with statin response and adverse effects in patients with familial hypercholesterolemia (FH) and analyzed their potential effects on protein structure and stability. METHODS: Clinical and laboratory data were obtained from 144 adult FH patients treated with statins. A panel of 32 PD genes was analyzed by exon-targeted gene sequencing. Deleterious variants were identified using prediction algorithms and their structural effects were analyzed by molecular modeling studies. RESULTS: A total of 102 variants were predicted as deleterious (83 missense, 8 stop-gain, 4 frameshift, 1 indel, 6 splicing). The variants ABCA1 rs769705621 (indel), LPA rs41267807 (p.Tyr2023Cys) and KIF6 rs20455 (p.Trp719Arg) were associated with reduced low-density lipoprotein cholesterol (LDLc) response to statins, and the LPL rs1801177 (p.Asp36Asn) with increased LDLc response (P < 0.05). LPA rs3124784 (p.Arg2016Cys) was predicted to increase statin response (P = 0.022), and ABCA1 rs769705621 to increase the risk of statin-related adverse events (SRAE) (P = 0.027). LPA p.Arg2016Cys and LPL p.Asn36Asp maintained interactions with solvent, LPA p.Tyr2023Cys reduced intramolecular interaction with Gln1987, and KIF6 p.Trp719Arg did not affect intramolecular interactions. DDMut analysis showed that LPA p.Arg2016Cys and p.Tyr2023Cys and LPL p.Asp36Asn caused energetically favorable changes, and KIF6 p.Trp719Arg resulted in unfavorable energetic changes, affecting protein stability. CONCLUSION: Deleterious variants in ABCA1, LPA, LPL and KIF6 are associated with variability in LDLc response to statins, and ABCA1 rs769705621 is associated with SRAE risk in FH patients. Molecular modeling studies suggest that LPA p.Tyr2023Cys and KIF6 p.Trp719Arg disturb protein conformational structure and stability.


Asunto(s)
Transportador 1 de Casete de Unión a ATP , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hiperlipoproteinemia Tipo II , Cinesinas , Lipoproteína Lipasa , Humanos , Cinesinas/genética , Masculino , Femenino , Persona de Mediana Edad , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Transportador 1 de Casete de Unión a ATP/genética , Lipoproteína Lipasa/genética , Adulto , Estabilidad Proteica , LDL-Colesterol/sangre , Polimorfismo de Nucleótido Simple
2.
Breast Cancer Res Treat ; 198(3): 447-461, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36786946

RESUMEN

BACKGROUND: Breast magnetic resonance imaging (MRI) has high sensitivity in detecting invasive neoplasms. Controversy remains about its impact on the preoperative staging of breast cancer surgery. This study evaluated survival and surgical outcomes of preoperative MRI in conservative breast cancer surgery. METHODS: A phase III, randomized, open-label, single-center trial including female breast cancer participants, stage 0-III disease, and eligible for breast-conserving surgery. We compared the role of including MRI in preoperative evaluation versus radiologic exam routine with mammography and ultrasound in breast cancer conservative candidates. The primary outcome was local relapse-free survival (LRFS), and secondary outcomes were overall survival (OS), mastectomy rate, and reoperation rate. RESULTS: 524 were randomized to preoperative MRI group (n = 257) or control group (n = 267). The survival analysis showed a 5.9-years LRFS of 99.2% in MRI group versus 98.9% in control group (HR = 0.72; 95% CI 0.12-4.28; p = 0.7) and an OS of 95.3% in the MRI group versus 96.3% in the control group (HR = 1.37 95% CI 0.59-3.19; p = 0.8). Surgical management changed in 21 ipsilateral breasts in the MRI group; 21 (8.3%) had mastectomies versus one in the control group. No difference was found in reoperation rates, 22 (8.7%) in the MRI group versus 23 (8.7%) in the control group (RR = 1.002; 95% CI 0.57-1.75; p = 0.85). CONCLUSION: Preoperative MRI increased the mastectomy rates by 8%. The use of preoperative MRI did not influence local relapse-free survival, overall survival, or reoperation rates.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Mastectomía/métodos , Tasa de Supervivencia , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Mastectomía Segmentaria/métodos , Cuidados Preoperatorios , Imagen por Resonancia Magnética/métodos
3.
Mol Biol Rep ; 50(11): 9165-9177, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37776414

RESUMEN

BACKGROUND: Familial hypercholesterolemia (FH) is caused by pathogenic variants in low-density lipoprotein (LDL) receptor (LDLR) or its associated genes, including apolipoprotein B (APOB), proprotein convertase subtilisin/kexin type 9 (PCSK9), and LDLR adaptor protein 1 (LDLRAP1). However, approximately 40% of the FH patients clinically diagnosed (based on FH phenotypes) may not carry a causal variant in a FH-related gene. Variants located at 3' untranslated region (UTR) of FH-related genes could elucidate mechanisms involved in FH pathogenesis. This study used a computational approach to assess the effects of 3'UTR variants in FH-related genes on miRNAs molecular interactions and to explore the association of these variants with molecular diagnosis of FH. METHODS AND RESULTS: Exons and regulatory regions of FH-related genes were sequenced in 83 FH patients using an exon-target gene sequencing strategy. In silico prediction tools were used to study the effects of 3´UTR variants on interactions between miRNAs and target mRNAs. Pathogenic variants in FH-related genes (molecular diagnosis) were detected in 44.6% FH patients. Among 59 3'UTR variants identified, LDLR rs5742911 and PCSK9 rs17111557 were associated with molecular diagnosis of FH, whereas LDLR rs7258146 and rs7254521 and LDLRAP1 rs397860393 had an opposite effect (p < 0.05). 3´UTR variants in LDLR (rs5742911, rs7258146, rs7254521) and PCSK9 (rs17111557) disrupt interactions with several miRNAs, and more stable bindings were found with LDLR (miR-4435, miR-509-3 and miR-502) and PCSK9 (miR-4796). CONCLUSION: LDLR and PCSK9 3´UTR variants disturb miRNA:mRNA interactions that could affect gene expression and are potentially associated with molecular diagnosis of FH.


Asunto(s)
Hiperlipoproteinemia Tipo II , MicroARNs , Humanos , Proproteína Convertasa 9/genética , Regiones no Traducidas 3'/genética , MicroARNs/genética , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/diagnóstico , Receptores de LDL/genética , Mutación
4.
BMC Med Educ ; 23(1): 236, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37046287

RESUMEN

BACKGROUND: Rapid demographic, epidemiological, technological, cultural/behavioural, and educational transitions, as they become more complex, demand new integrated and complementary professional skills and abilities. Interprofessional Education (IPE) is a promising alternative to deal with these changes, especially in courses in the health area. This systematic review was to explore the potentialities and limitations of IPE, from the perspective of undergraduate students, through a thematic synthesis of qualitative studies. METHODS: A thematic synthesis of qualitative studies was conducted. The question elaborated for this review was: "What is the impact of interprofessional education on the teaching and learning of students in the health area inserted in Higher Education Institutions?". The search strategy was performed in the electronic databases PubMed, Latin American and Caribbean Literature in Health Sciences (LILACS), Cochrane Library, and Scientific Electronic Library Online (SciELO). In addition, searches were carried out in grey literature on the ERIC platforms, ProQuest Disserts and Theses, and Academic Google. The assessment of the quality of the studies was carried out using the Critical Appraisal Skills Programme tool. Data were summarized through thematic synthesis. From the databases, 8,793 studies were identified. After standardized filters procedures, critical summaries, and assessment of relevance to the eligibility criteria, 14 articles were included. RESULTS: The synthesis of the studies revealed the potential of this teaching approach, arranged in three analytical themes: learning from each other and about them; the value of education and interprofessional practice; patient-centred health care. On the other hand, some limitations were also identified, such as barriers related to EIP; the difficulties related to teaching methodologies. CONCLUSION: Overcoming the identified limitations can enhance the results of the IPE, in view of its impact on the education of students and on the health care of the population.


Asunto(s)
Educación Interprofesional , Estudiantes , Humanos , Atención a la Salud , Escolaridad , Investigación Cualitativa , Relaciones Interprofesionales
5.
BMC Cancer ; 22(1): 391, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35410265

RESUMEN

OBJECTIVE: To present a systematic review of the literature and a meta-analysis evaluating the oncological safety of autologous fat grafting (AFG). SUMMARY BACKGROUND DATA: AFG for breast reconstruction presents difficulties during follow-up radiological exams, and the oncological potential of grafted fat is uncertain. Previous studies confirmed that the fatty tissue could be transferred under a good condition suitable would not interfere with mammographic follow-up, although the issue of oncological safety remains. METHODS: We reviewed the literature published until 01/18/2021. The outcomes were overall survival (OS), disease-free survival (DFS), and local recurrence (LR). We included studies that evaluated women with breast cancer who undergone surgery followed by reconstruction with AFG. We synthesized data using the inverse variance method on the log-HR (log of the hazard ratio) scale for time-to-event outcomes using RevMan. We assessed heterogeneity using the Chi2 and I2 statistics. RESULTS: Fifteen studies evaluating 8541 participants were included. The hazard ratios (HR) could be extracted from four studies, and there was no difference in OS between the AFG group and control (HR 0.9, 95% CI 0.53 to 1.54, p = 0.71, I2 = 58%, moderate certainty evidence), and publication bias was not detected. The HR for DFS could be extracted from six studies, and there was no difference between the AFG group and control (HR 1.01, 95% CI 0.73 to 1.38, p = 0.96, I2 = 0%, moderate certainty evidence). The HR for LR could be extracted from ten studies, and there was no difference between the AFG group and control (HR 0.86, 95% CI 0.66 to 1.12, p = 0.43, I2 = 1%, moderate certainty evidence). CONCLUSION: According to the current evidence, AFG is a safe technique of breast reconstruction for patients that have undergone BC surgery and did not affect OS, DFS, or LR.


Asunto(s)
Neoplasias de la Mama , Mamoplastia , Tejido Adiposo , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mamoplastia/efectos adversos , Mamoplastia/métodos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Trasplante Autólogo/efectos adversos , Trasplante Autólogo/métodos
6.
Environ Res ; 206: 112598, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34953887

RESUMEN

The toxicity of microplastic particles (MPs) on aquatic environments has been widely reported; however, their effects on protists are still contradictory. For example, it is unclear if cell size and cell wall have a role in shaping the response of flagellates to MPs. In this study, seven marine flagellated microalgae (six Dinoflagellates and one Raphidophyceae) were incubated with 10 mg L-1 MPs (polystyrene plastic micro-spheres, 1 µm diameter) to address the above question by measuring different response variables, i.e., growth, optimal photochemical efficiency (Fv/Fm), chlorophyll-a (Chl-a) content, superoxide dismutase (SOD) activity, and cell morphology. The effect of MPs on growth and Fv/Fm showed species-specificity effects. Maximum and minimum MPs-induced inhibitions were detected in Karenia mikimotoi (76.43%) and Akashiwo sanguinea (10.16%), respectively, while the rest of the species showed intermediate responses. The presence of MPs was associated with an average reduction of Chl-a content in most cases and with a higher superoxide dismutase activity in all cases. Seven species were classified into two groups by the variation of Chl-a under MPs treatment. One group (Prorocentrum minimum and Karenia mikimotoi) showed increased Chl-a, while the other (P. donghaiense, P. micans, Alexandrium tamarense, Akashiwo sanguinea, Heterosigma akashiwo) showed decreased Chl-a content. The MPs-induced growth inhibition was negatively correlated with cell size in the latter group. SEM images further indicated that MPs-induced malformation in the smaller cells (e.g., P. donghaiense and K. mikimotoi) was more severe than the bigger cells (e.g., A. sanguinea and P. micans), probably due to a relatively higher ratio of the cell surface to cell volume in the former. These results implicate that the effect of MPs on marine flagellated microalgae was related to the cell size among most species but not cell wall. Thus plastic pollution may have size-dependent effects on phytoplankton in future scenarios.


Asunto(s)
Microalgas , Contaminantes Químicos del Agua , Pared Celular/química , Dinoflagelados , Microplásticos , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis
7.
Environ Res ; 206: 112421, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34838759

RESUMEN

Trace metals bioaccumulate in aquatic organisms and some of them biomagnify through food webs, posing a threat to the organisms or their human consumers. Although the trophodynamics of many trace metals is well known in the northern hemisphere, much less is known about metals in aquatic food webs from cold and remote coastal zones of the southern hemisphere. To fill this gap, we investigated the trophodynamics of Al, Co, Cr, Li, Mo, Ni, Sr, and V, which were measured in marine macroinvertebrates and fishes from inshore and offshore locations in each of the Chilean Patagonia and the Antarctic Peninsula area. In Patagonia, there was biodilution of these metals across the whole food web, while biomagnification of Li and Ni was significantly found across the lower food web at the offshore site. In Antarctica, significant biodilution of Al, Li, Ni, Mo, Sr and V occurred through the whole food web for the inshore site, but no tendency (biodilution or biomagnification) was found (p > 0.05) across the organisms at lower trophic levels for the offshore site. Our data suggest that the geographic location and species influences the trophodynamics of these trace elements and expand our understanding of metal fate in remote locations of the southern hemisphere.


Asunto(s)
Oligoelementos , Contaminantes Químicos del Agua , Animales , Organismos Acuáticos , Monitoreo del Ambiente , Peces , Cadena Alimentaria , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis
8.
Proc Natl Acad Sci U S A ; 116(21): 10435-10440, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31048503

RESUMEN

Circadian clocks generate rhythms in cellular functions, including metabolism, to align biological processes with the 24-hour environment. Disruption of this alignment by shift work alters glucose homeostasis. Glucose homeostasis depends on signaling and allosteric control; however, the molecular mechanisms linking the clock to glucose homeostasis remain largely unknown. We investigated the molecular links between the clock and glycogen metabolism, a conserved glucose homeostatic process, in Neurospora crassa We find that glycogen synthase (gsn) mRNA, glycogen phosphorylase (gpn) mRNA, and glycogen levels, accumulate with a daily rhythm controlled by the circadian clock. Because the synthase and phosphorylase are critical to homeostasis, their roles in generating glycogen rhythms were investigated. We demonstrate that while gsn was necessary for glycogen production, constitutive gsn expression resulted in high and arrhythmic glycogen levels, and deletion of gpn abolished gsn mRNA rhythms and rhythmic glycogen accumulation. Furthermore, we show that gsn promoter activity is rhythmic and is directly controlled by core clock component white collar complex (WCC). We also discovered that WCC-regulated transcription factors, VOS-1 and CSP-1, modulate the phase and amplitude of rhythmic gsn mRNA, and these changes are similarly reflected in glycogen oscillations. Together, these data indicate the importance of clock-regulated gsn transcription over signaling or allosteric control of glycogen rhythms, a mechanism that is potentially conserved in mammals and critical to metabolic homeostasis.


Asunto(s)
Relojes Circadianos , Regulación de la Expresión Génica , Glucógeno Sintasa/metabolismo , Glucógeno/metabolismo , Neurospora crassa/metabolismo , Proteínas Fúngicas/metabolismo , Glucógeno Sintasa/genética , Neurospora crassa/genética
9.
ScientificWorldJournal ; 2022: 3885745, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36132437

RESUMEN

Sustained bioenergy production from organisms that thrive in high salinity, low oxygen, and low nutrition levels is useful in monitoring hypersaline polluted environments. Microbial fuel cell (MFC) studies utilizing single species halophiles under salt concentrations higher than 1 M and as a closed microbial system are limited. The current study aimed to establish baseline voltage, current, and power density from a dual-chambered MFC utilizing the halophile Halobacterium salinarum NRC-1. MFC performance was determined with two different electrode sizes (5 cm2 and 10 cm2), under oscillating and nonoscillating conditions, as well as in a stacked series. A closed dual-chamber MFC system of 100 mL capacity was devised with Halobacterium media (4.3 M salt concentration) as both anolyte and catholyte, with H. salinarum NRC-1 being the anodic organism. The MFC measured electrical output over 7, 14, 28, and 42 days. MFC output increased with 5 cm2 sized electrodes under nonoscillating (p < 0.0001) relative to oscillating conditions. However, under oscillating conditions, doubling the electrode size increased MFC output significantly (p = 0.01). The stacked series MFC, with an electrode size of 10 cm2, produced the highest power density (1.2672 mW/m2) over 14 days under oscillation. Our results highlight the potentiality of H. salinarum as a viable anodic organism to produce sustained voltage in a closed-MFC system.


Asunto(s)
Fuentes de Energía Bioeléctrica , Electricidad , Electrodos , Halobacterium salinarum , Oxígeno
10.
Med Mycol ; 59(10): 993-1005, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34036352

RESUMEN

Silver compounds are widely known for their antimicrobial activity, but can exert toxic effects to the host. Among the strategies to reduce its toxicity, incorporation into biopolymers has shown promising results. We investigated the green syntheses of silver nanoparticles (AgNPs) and their functionalization in a chitosan matrix (AgNPs@Chi) as a potential treatment against Candida spp. Inhibitory concentrations ranging between 0.06 and  1 µg/ml were observed against distinct Candida species. Nanocomposite-treated cells displayed cytoplasmic degeneration and a cell membrane and wall disruption. Silver nanocomposites in combination with fluconazole and amphotericin B showed an additive effect when analyzed by the Bliss method. The low cytotoxicity displayed in mammalian cells and in the Galleria mellonella larvae suggested their potential use in vivo. When tested as a topical treatment against murine cutaneous candidiasis, silver nanocomposites reduced the skin fungal burden in a dose-response behavior and favored tissue repair. In addition, the anti-biofilm effect of AgNPs@Chi in human nail model was demonstrated, suggesting that the polymeric formulation of AgNPs does not affect antifungal activity even against sessile cells. Our results suggest that AgNPs@Chi seems to be a less toxic and effective topical treatment for superficial candidiasis. LAY SUMMARY: This study demonstrated the efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Candida. AgNPs incorporated in chitosan displayed a reduced toxicity. Tests in infected mice showed the effectiveness of the treatment. AgNPs-chitosan could be an alternative to combat candidiasis.


Asunto(s)
Candidiasis , Quitosano , Nanopartículas del Metal , Nanocompuestos , Enfermedades de los Roedores , Animales , Antibacterianos , Candidiasis/tratamiento farmacológico , Candidiasis/veterinaria , Ratones , Pruebas de Sensibilidad Microbiana/veterinaria , Plata/farmacología
11.
Photochem Photobiol Sci ; 20(1): 123-137, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33721244

RESUMEN

Solar water disinfection (SODIS) is an effective and inexpensive microbiological water treatment technique, applicable to communities lacking access to safely managed drinking water services, however, the lower volume of treated water per day (< 2.5 L per batch) is a limitation for the conventional SODIS process. To overcome this limitation, a continuous-flow solar water disinfection system was developed and tested for inactivation of Acanthamoeba castellanii cysts and Escherichia coli, Salmonella Typhimurium, Enterococcus faecalis, and Pseudomonas aeruginosa. The system consisted of a solar heater composed of a cylindrical-parabolic concentrator and a UV irradiator formed by a fresnel-type flat concentrator combined with a cylindrical-parabolic concentrator. Deionized water with low or high turbidity (< 1 or 50 nephelometric turbidity unit (NTU) where previously contaminated by 108 Cysts/L or 105-106 CFU/mL of each of four bacterial species. Then was pumped from the heating tank flowing through the heater and through the UV irradiator, then returning to the heating tank, until reaching 45, 55, 60 or 70 °C. The water was kept at the desired temperature, flowing through the UV irradiator for 0.5 and 10 min. Trophozoites were not recovered from cysts (during 20 days of incubation) when water with < 1 NTU was exposed to UV and 60 °C for 0.5 min. In water with 50 NTU, the same result was obtained after 10 min. In water with < 1 NTU, the inactivation of all bacteria was achieved when the water with < 1 NTU was exposed to 55 °C and UV for 0.5 min; in water, with 50 NTU the same result was achieved by exposure to 60 °C and UV for 0.5 min. The prototype processes 1 L of water every 90s. The system is effective and has the potential to be applied as an alternative to the large-scale public drinking water supply.


Asunto(s)
Acanthamoeba castellanii/efectos de la radiación , Bacterias/efectos de la radiación , Rayos Ultravioleta , Purificación del Agua/métodos , Desinfección/métodos , Temperatura , Purificación del Agua/instrumentación
12.
Mol Phylogenet Evol ; 143: 106692, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31770589

RESUMEN

Worldwide distributed tropical savannas were established only in the Miocene, with climatic cooling and rise of C4 grasses. However, there is evidence for an earlier presence of savanna-like vegetation in southern parts of South America. Here we investigated the biogeographic history of a clade of solitary bees which have endemic groups in areas covered by savannas and other types of open vegetation as well as forested areas. We hypothesized that these bees originated in savanna-like biomes and that shifts to forested areas and floral host shifts increased species diversification along their evolutionary history. We reconstructed a comprehensive phylogeny for Tapinotaspidini bees based majorly on original DNA sequences. We then used macroevolutionary tools to estimate ancestral range area and reconstructed ancestral habitat (open versus forested) and host plant association to analyze the effects of shifts in vegetation type and flower hosts on their diversification. Tapinotaspidini bees originated in the Paleocene and in a savanna-type, Cerrado-like, which is reinforced by reconstruction of open vegetation as the most probable ancestral area, thus bringing additional evidence to a much earlier origin of this vegetation type in South America. Shifts to forested areas occurred at least three times in a period of 30 Ma and were responsible for slight increases in diversification rates. Malpighiaceae is the ancestral floral host; host broadening occurred only in the Miocene and at least in three occasions. Host shifts, i.e. from Malpighiaceae to other oil families, occurred in the Eocene and Miocene. Both host broadening and host shifts did not significantly alter diversification rates, however exploitation of other oil sources were important in occupying new habitats. The link between biomes and host plant shifts and changes in diversification rate brings us additional insights into the evolution of bees and associated flora in South America.


Asunto(s)
Abejas/clasificación , Animales , Abejas/genética , Abejas/fisiología , Evolución Biológica , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Fósiles/historia , Pradera , Historia Antigua , Malpighiaceae/crecimiento & desarrollo , Malpighiaceae/fisiología , Filogenia , Filogeografía , América del Sur
13.
Curr Treat Options Oncol ; 19(5): 23, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29663173

RESUMEN

OPINION STATEMENT: Neoadjuvant endocrine therapy (NET) with Ki67-based response monitoring is a practical, cost-effective approach to the management of clinical stage II and III estrogen receptor-positive (ER+) breast cancer. In addition to marked improvements in rates of breast conservation, the identification of extreme responders on the basis of the preoperative endocrine prognostic index (PEPI) provides a rationale to avoid chemotherapy on the basis of highly favorable prognosis in some patients. Finally, samples accrued from patients treated with neoadjuvant therapy are providing valuable insights into the molecular basis for intrinsic resistance to endocrine therapy and promise a more rational basis and precise approach to the systemic treatment of ER+ breast cancer.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Terapia Neoadyuvante , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Humanos , Estadificación de Neoplasias , Pronóstico , Receptores de Estrógenos/genética , Receptores de Progesterona/genética
14.
Curr Treat Options Oncol ; 19(5): 24, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29666928

RESUMEN

OPINION STATEMENT: Endocrine treatment resistance eventually develops during adjuvant and even more often during hormonal treatment for advanced breast cancer (ABC). An ESR1 gene mutation, which encodes for the estrogen receptor (ER) protein, is one of the potential mechanisms of therapy resistance. The ESR1 mutations result in conformational changes in the ER leading to subsequent estrogen-independent transcriptional activity. These mutations are found at a lower level in early stage when compared to metastatic BC, more often through selective pressure after aromatase inhibitor (AI) treatment. Recent studies have explored the role of ESR1 mutations as potential prognostic and predictive biomarkers and showed that ESR1 mutations are likely associated with a more aggressive disease. However, definitive associations with outcome in order to make a specific treatment recommendation are yet to be found. The development of targeted therapy directed to ESR1-mutated clones is an appealing concept, and preclinical and clinical works are in progress. ESR1 mutations represent an exciting field with a rapidly increasing number of recent publications that will likely advance the knowledge of treatment resistance mechanisms and pave the way into more individualized patient endocrine treatment.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/genética , Pronóstico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Mutación
16.
Breast Cancer Res Treat ; 165(2): 355-364, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28612227

RESUMEN

PURPOSE: The recent publication of the ACOSOG Z1031 trial results demonstrated that Ki-67 proliferation marker-based neoadjuvant endocrine therapy response monitoring could be used for tailoring the use of adjuvant chemotherapy in ER+HER2-negative breast cancer patients. In this paper, we describe the development of the Ki-67 clinical trial assay used for this study. METHODS: Ki-67 assay assessment focused on reproducing a 2.7% Ki-67 cut-point (CP) required for calculating the Preoperative Endocrine Prognostic Index and a 10% CP for poor endocrine therapy response identification within the first month of neoadjuvant endocrine treatment. Image analysis was assessed to increase the efficiency of the scoring process. Clinical outcome concordance for two independent Ki-67 scores was the primary performance metric. RESULTS: Discordant scores led to a triage approach where cases with complex histological features that software algorithms could not resolve were flagged for visual point counting (17%). The final Ki-67 scoring approach was run on T1/2 N0 cases from the P024 and POL trials (N = 58). The percent positive agreement for the 2.7% CP was 87.5% (95% CI 61.7-98.5%); percent negative agreement 88.9% (95% CI: 65.3-98.6%). Minor discordance did not affect the ability to predict similar relapse-free outcomes (Log-Rank P = 0.044 and P = 0.055). The data for the 10% early triage CP in the POL trial were similar (N = 66), the percentage positive agreement was 100%, and percent negative agreement 93.55% (95% CI: 78.58-99.21%). The independent survival predictions were concordant (Log-rank P = 0.0001 and P = 0.01). CONCLUSIONS: We have developed an efficient and reproducible Ki-67 scoring system that was approved by the Clinical Trials Evaluation Program for NCI-supported neoadjuvant endocrine therapy trials. Using the methodology described here, investigators are able to identify a subgroup of patients with ER+HER2-negative breast cancer that can be safely managed without the need of adjuvant chemotherapy.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Antígeno Ki-67/metabolismo , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/mortalidad , Quimioterapia Adyuvante , Toma de Decisiones Clínicas , Femenino , Humanos , Estimación de Kaplan-Meier , Terapia Neoadyuvante , Pronóstico , Curva ROC , Reproducibilidad de los Resultados , Resultado del Tratamiento
17.
Proc Natl Acad Sci U S A ; 111(32): 11738-43, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-25071196

RESUMEN

Interactions between planktonic organisms, such as detection of prey, predators, and mates, are often mediated by fluid signals. Consequently, many plankton predators perceive their prey from the fluid disturbances that it generates when it feeds and swims. Zooplankton should therefore seek to minimize the fluid disturbance that they produce. By means of particle image velocimetry, we describe the fluid disturbances produced by feeding and swimming in zooplankton with diverse propulsion mechanisms and ranging from 10-µm flagellates to greater than millimeter-sized copepods. We show that zooplankton, in which feeding and swimming are separate processes, produce flow disturbances during swimming with a much faster spatial attenuation (velocity u varies with distance r as u ∝ r(-3) to r(-4)) than that produced by zooplankton for which feeding and propulsion are the same process (u ∝ r(-1) to r(-2)). As a result, the spatial extension of the fluid disturbance produced by swimmers is an order of magnitude smaller than that produced by feeders at similar Reynolds numbers. The "quiet" propulsion of swimmers is achieved either through swimming erratically by short-lasting power strokes, generating viscous vortex rings, or by "breast-stroke swimming." Both produce rapidly attenuating flows. The more "noisy" swimming of those that are constrained by a need to simultaneously feed is due to constantly beating flagella or appendages that are positioned either anteriorly or posteriorly on the (cell) body. These patterns transcend differences in size and taxonomy and have thus evolved multiple times, suggesting a strong selective pressure to minimize predation risk.


Asunto(s)
Modelos Biológicos , Zooplancton/fisiología , Animales , Fenómenos Biomecánicos , Cilióforos/fisiología , Copépodos/fisiología , Dinoflagelados/fisiología , Ingestión de Alimentos/fisiología , Conducta Alimentaria/fisiología , Femenino , Hidrodinámica , Masculino , Movimiento/fisiología , Reología , Transducción de Señal , Natación/fisiología , Grabación en Video
18.
Mem Inst Oswaldo Cruz ; 112(10): 681-691, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28953996

RESUMEN

BACKGROUND: Knowledge on synanthropic phlebotomines and their natural infection by Leishmania is necessary for the identification of potential areas for leishmaniasis occurrence. OBJECTIVE: To analyse the occurrence of Phlebotominae in gallery forests and household units (HUs) in the city of Palmas and to determine the rate of natural infection by trypanosomatids. METHODS: Gallery forests and adjacent household areas were sampled on July (dry season) and November (rainy season) in 2014. The total sampling effort was 960 HP light traps and eight Shannon traps. Trypanosomatids were detected in Phlebotominae females through the amplification of the SSU rDNA region, and the positive samples were used in ITS1-PCR. Trypanosomatid species were identified using sequencing. FINDINGS: A total of 1,527 sand flies representing 30 species were captured in which 949 (28 spp.) and 578 (22 spp.) were registered in July and November, respectively. In July, more specimens were captured in the gallery forests than in the HUs, and Nyssomyia whitmani was particularly frequent. In November, most of the specimens were found in the HUs, and again, Ny. whitmani was the predominant species. Lutzomyia longipalpis was commonly found in domestic areas, while Bichromomyia flaviscutellata was most frequent in gallery forests. Molecular analysis of 154 pools of females (752 specimens) identified Leishmania amazonensis, L. infantum, and Crithidia fasciculata in Ny. whitmani, as well as L. amazonensis in Lu. longipalpis, Trypanosoma sp. and L. amazonensis in Pintomyia christenseni, and L. amazonensis in both Psathyromyia hermanlenti and Evandromyia walkeri. MAIN CONCLUSIONS: These results show the importance of gallery forests in maintaining Phlebotominae populations in the dry month, as well as their frequent occurrence in household units in the rainy month. This is the first study to identify Leishmania, Trypanosoma, and Crithidia species in Phlebotominae collected in Palmas, Tocantins, Brazil.


Asunto(s)
Pradera , Leishmania/aislamiento & purificación , Psychodidae/parasitología , Animales , Femenino , Bosques , Insectos Vectores , Psychodidae/clasificación
19.
AJR Am J Roentgenol ; 206(5): 1124-30, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27010761

RESUMEN

OBJECTIVE: The selection of breast cancer patients as candidates for nipple-sparing mastectomy (NSM) is dependent on the preoperative detection of neoplastic involvement of the nipple-areola complex (NAC). This cross-sectional study was designed to evaluate the accuracy of preoperative breast MRI as a noninvasive method to predict neoplastic involvement of the nipple. MATERIALS AND METHODS: We included 165 female breast cancer patients with a surgical plan that included total mastectomy or breast conservation surgery with the removal of the NAC. All patients underwent MRI before surgery on a 1.5-T unit with a 4-channel in vivo dedicated surface breast coil. One radiologist who was blinded to the results of the histologic evaluations of the specimens evaluated the MRI studies. RESULTS: Of the 170 mastectomy specimens evaluated, 37 (21.8%) had neoplastic involvement of the NAC. The MRI findings of enhancement between the index lesion and the NAC and of nipple retraction were considered statistically significant predictors of nipple involvement in breast cancer patients (p < 0.01 and p = 0.01, respectively). The negative predictive value of the combination of these MRI findings was 83.3%. CONCLUSION: Breast MRI is a safe noninvasive method to preoperatively evaluate breast cancer patients eligible for NSM with a high specificity and a high negative predictive value when enhancement between the index lesion and the nipple and nipple retraction are analyzed.


Asunto(s)
Neoplasias de la Mama/patología , Imagen por Resonancia Magnética , Pezones/patología , Neoplasias de la Mama/cirugía , Estudios Transversales , Femenino , Humanos , Mastectomía Segmentaria , Mastectomía Simple , Pezones/cirugía , Valor Predictivo de las Pruebas , Cuidados Preoperatorios
20.
Exp Parasitol ; 162: 1-6, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26724377

RESUMEN

Trypanosoma cruzi is mainly transmitted by blood-sucking triatomines, but other routes also have epidemiological importance, such as blood transfusion and congenital transmission. Although the possibility of sexual transmission of T. cruzi has been suggested since its discovery, few studies have been published on this subject. We investigated acquisition of T. cruzi by sexual intercourse in an experimental murine model. Male and female mice in the chronic phase of Chagas disease were mated with naive partners. Parasitological, serological and molecular tests demonstrated the parasites in tissues and blood of partners. These results confirm the sexual transmission of T. cruzi in mice.


Asunto(s)
Enfermedad de Chagas/transmisión , Enfermedades de Transmisión Sexual/transmisión , Trypanosoma cruzi/fisiología , Animales , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/inmunología , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/patología , ADN Protozoario/análisis , ADN Protozoario/sangre , ADN Protozoario/aislamiento & purificación , Modelos Animales de Enfermedad , Femenino , Gónadas/parasitología , Corazón/parasitología , Intestinos/parasitología , Masculino , Ratones , Ratones Endogámicos BALB C , Músculo Esquelético/parasitología , Carga de Parásitos , Enfermedades de Transmisión Sexual/parasitología , Enfermedades de Transmisión Sexual/patología , Trypanosoma cruzi/genética , Trypanosoma cruzi/inmunología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA