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1.
Pathogens ; 12(5)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37242313

RESUMEN

Arthropods transmit arboviruses via mosquito and tick bites to humans and other animals. The genus flavivirus, which causes diseases, sequelae, and thousands of deaths, mainly in developing and underdeveloped countries, is among the arboviruses of interest to public health. Given the importance of early and accurate diagnosis, this review analyzes the methods of direct detection of flaviviruses, such as reverse transcription loop-mediated isothermal amplification, microfluidics, localized surface plasmon resonance, and surface-enhanced Raman scattering, and presents the advantages, disadvantages, and detection limits identified in studies reported in the literature for each methodology. Among the different methods available, it is essential to balance four fundamental indicators to determine the ideal test: good sensitivity, high specificity, low false positive rate, and rapid results. Among the methods analyzed, reverse transcription loop-mediated isothermal amplification stands out, owing to result availability within a few minutes, with good sensitivity and specificity; in addition, it is the best-characterized methodology.

2.
PeerJ ; 11: e14624, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36647445

RESUMEN

Salt stress is one of the most severe abiotic stresses affecting plant growth and development. The application of silicon (Si) is an alternative that can increase the tolerance of plants to various types of biotic and abiotic stresses. The objective was to evaluate salt stress's effect in vitro and Si's mitigation potential on Aechmea blanchetiana plants. For this purpose, plants already established in vitro were transferred to a culture medium with 0 or 14 µM of Si (CaSiO3). After growth for 30 days, a stationary liquid medium containing different concentrations of NaCl (0, 100, 200, or 300 µM) was added to the flasks. Anatomical and physiological analyses were performed after growth for 45 days. The plants cultivated with excess NaCl presented reduced root diameter and effective photochemical quantum yield of photosystem II (PSII) (ΦPSII) and increased non-photochemical dissipation of fluorescence (qN). Plants that grew with the presence of Si also had greater content of photosynthetic pigments and activity of the enzymes of the antioxidant system, as well as higher values of maximum quantum yield of PSII (FV/FM), photochemical dissipation coefficient of fluorescence (qP) and fresh weight bioaccumulation of roots and shoots. The anatomical, physiological and biochemical responses, and growth induced by Si mitigated the effect of salt stress on the A. blanchetiana plants cultivated in vitro, which can be partly explained by the tolerance of this species to grow in sandbank (Restinga) areas.


Asunto(s)
Bromeliaceae , Cloruro de Sodio , Cloruro de Sodio/farmacología , Silicio/farmacología , Bromeliaceae/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo
3.
Front Plant Sci ; 14: 1298591, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38179484

RESUMEN

Oats are known for their nutritional value and also for their beneficial properties on human health, such as the reduction of cholesterol levels and risk of coronary heart disease; they are an important export product for Chile. During the last decade (2010-2022) over 90% of the oat cultivated area in Chile has been covered with Avena sativa L. cv. Supernova INIA. This lack of genetic diversity in a context of climate change could limit the long-term possibility of growing oats in Chile. The present study is a phenotypic and genetic analysis of 132 oat cultivars and pure lines of diverse origin that can be considered as potential breeding material. The germplasm was evaluated for 28 traits and analyzed with 14 SSR markers. The effects of genotypes on phenotype were significant over all traits (P ≤ 0.05). Most traits exhibited moderate to high broad-sense heritability with exceptions such as yield (H2 = 0.27) and hulls staining (H2 = 0.32). Significant undesirable correlations between traits were generally of small biological importance, which is auspicious for achieving breeding objectives. Some of the heritability data and correlations provided here have not been previously reported. The overall phenotypic diversity was high (H' = 0.68 ± 0.18). The germplasm was grouped into three phenotypic clusters, differing in their qualities for breeding. Twenty-six genotypes outperforming Supernova INIA were identified for breeding of conventional food-oats. The genetic diversity of the germplasm was moderate on average (He = 0.58 ± 0.03), varying between 0.32 (AM22) and 0.77 (AME178). Two genetic subpopulations supported by the Structure algorithm exhibited a genetic distance of 0.24, showing low divergence of the germplasm. The diversity and phenotypic values found in this collection of oat genotypes are promising with respect to obtaining genetic gain in the short term in breeding programs. However, the similar genetic diversity, higher phenotypic diversity, and better phenotypic performance of the germplasm created in Chile compared to foreign germplasm suggest that germplasm harboring new genetic diversity will be key to favor yield and quality in new oat cultivars in the long term.

4.
Foods ; 11(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35159403

RESUMEN

The chemical composition and quality of honey depend on the floral and geographical origin, extraction techniques, and storage, resulting in a unique product for each area. Currently, consumers are not only concerned about the chemical composition, quality, and food safety of honey, but also about its origin. The objective of this study was to characterize honeys produced in Chile's central-southern region from a mineral and botanical perspective, thus adding value through differentiation by origin. Two hundred honey samples were used and underwent analysis such as melissopalynological composition, nutritional composition, and color. Forty-seven melliferous floral species were identified, out of which 24 correspond to exotic species and 23 to native species. Fifty-six percent were classified as monofloral honeys, 2% as bifloral, and 42% as multifloral. Moisture mean values (17.88%), diastase activity (15.53 DN), hydroxymethylfurfural (2.58 mg/kg), protein (0.35%), and ash (0.25%) comply with the ranges established by both the national and the international legislation; standing out as honeys of great nutritional value, fresh, harvested under optimal maturity conditions, and absence fermentation. Regarding color, light amber was prevalent in most territories. The territory where honey was produced, denoted relevant differences in all the parameters studied.

5.
Gac Med Mex ; 156(Suppl 1): S1-S45, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33103663

RESUMEN

To identify this increasingly common pathology, known as multiple myeloma (MM), it is necessary to refer to the specific factors that characterize it; to this end, the classic criteria known as CRAB (hyperkalemia, renal failure, anemia, and lytic lesions) are available, in which renal failure is one of the most frequent complications. Recently, three indisputable biomarkers have been described for the diagnostic support for MM, which are: more than 10% of clonal plasma cells in bone marrow or, a biopsy that corroborates the presence of a plasmacytoma, light chain ratio ≥ 100 mg/dL and more than one focal lesion on magnetic resonance imaging. A differential diagnosis for plasma cell leukemia, solitary bone plasmacytoma, and extramedullary plasmacytoma should always be considered. Being this an incurable disease, a lot of research has been done regarding its therapeutic management, whose main objective is the disappearance of plasma cells and the patient clinical improvement. Melphalan was the first drug that showed a benefit in 1958 and afterward, with the addition of a steroid as a second drug, it was possible to improve response rates. Subsequently, different molecules were studied, forming multiple combinations, and achieving better rates of overall survival and progression-free survival. Years later, with the arrival of proteasome inhibitors such as bortezomib, and immunomodulators such as thalidomide and lenalidomide, an important turnaround in the disease has been seen, as deeper responses, more prolonged remissions, and improvement in the quality of life of patients have been achieved. This consensus has the purpose of integrating a group of Mexican specialists and promoting the updating of this pathology.


Para identificar una patología cada vez más común, conocida como mieloma múltiple, es necesario hacer alusión de los factores específicos que la caracterizan. Para ello existen los clásicos criterios conocidos como CRAB (hipercalcemia, insuficiencia renal, anemia y lesiones líticas), siendo la insuficiencia renal una de sus complicaciones más frecuentes. Recientemente se han descrito tres biomarcadores indiscutibles para el apoyo diagnóstico del mieloma múltiple, que son: más del 10% de células plasmáticas clonales en medula ósea o biopsia que corrobora la presencia de un plasmocitoma, relación de cadenas ligeras ≥ 100 mg/dl y más de una lesión focal en resonancia magnética. Se debe tomar siempre en cuenta el diagnóstico diferencial con leucemia de células plasmáticas, plasmocitoma óseo solitario y plasmocitoma extramedular. Al ser una enfermedad incurable, se ha investigado mucho en cuanto al manejo terapéutico, el cual tiene como objetivo principal la desaparición de las células plasmáticas y la mejoría clínica del paciente. El primer fármaco que demostró algún beneficio fue el melfalán en el año 1958 y posteriormente al adicionar un esteroide como segundo fármaco se logró mejorar las tasas de respuesta. Después se fueron estudiando diferentes moléculas, con las que se han realizado múltiples combinaciones, alcanzando mejores tasas de supervivencia global y supervivencia libre de progresión. Años más tarde, con la llegada de los inhibidores de proteosoma como el bortezomib, así como de los agentes inmunomoduladores como la talidomida y la lenalidomida, se presenta un giro importante en la enfermedad, ya que se logran respuestas más profundas, periodo de remisiones más prolongadas y mejoría en la calidad de vida de los pacientes. Este consenso tiene la finalidad de integrar a un grupo de especialistas mexicanos y promover la actualización de esta patología.


Asunto(s)
Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Algoritmos , Humanos , México , Mieloma Múltiple/complicaciones
6.
Biochimie ; 168: 210-219, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31759936

RESUMEN

Glyceroneogenesis is important for the maintenance of fat content in white adipose tissue (WAT). An increase in WAT, and especially the pattern of fat distribution, specifically in visceral depots, potentially contributes to cardiovascular and metabolic diseases, such as type 2 diabetes mellitus, myocardial infarction and hypertension. Recent studies have shown important differences in glyceroneogenesis of different fat sites under the administration of glucocorticoids (GCs). Such differences need to be analysed with criteria evidencing the parameter studied, the type of corticoid, the form of administration and also the tissue studied. PubMed, Scopus and Virtual Health Library were used to search for articles that analysed the effect of GCs on glyceroneogenesis in different sites of adipose tissue in mammals and primary cultures. GCs decrease the glyceroneogenesis in epididymal WAT (EWAT) and also decrease the expression of the mRNA, content and activity of phosphoenolpyruvate carboxykinase (PEPCK-C), key enzyme of glyceroneogenesis. However, in retroperitoneal WAT (RWAT), although there is no consensus about the effect of GCs on PEPCK mRNA, GCs increase PEPCK-C activity and glyceroneogenesis flux. In inguinal WAT (IWAT) an in vitro study showed an increase in the PEPCK mRNA induced by dexamethasone. However, prednisolone does not change glyceroneogenesis flux. In interscapular brown adipose tissue (IBAT) prednisolone or dexamethasone does not change PEPCK-C activity in control diet-fed rats but led to a decrease in PEPCK-C activity in fasted- or high-fat/low-carbohydrate diet-fed rats, as well as in suckling rats. Despite that fact that GCs have different potencies, the same dose of dexamethasone reduces PEPCK-C activity in EWAT, but not in RWAT and IBAT from control-diet fed rats. In summary, the data presented in this article show that GCs differentially regulate glyceroneogenesis in different sites of adipose tissue. Further experiments are needed to firmly establish our hypothesis and clarify the mechanisms involved.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Glucocorticoides/farmacología , Glicerol/metabolismo , Lipogénesis/efectos de los fármacos , Fosfoenolpiruvato Carboxiquinasa (ATP)/metabolismo , Adiposidad/fisiología , Animales , Humanos , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Ratas Wistar
7.
Oncotarget ; 8(43): 74233-74243, 2017 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-29088781

RESUMEN

Identifying founder mutations in BRCA1 and BRCA2 in specific populations constitute a valuable opportunity for genetic screening. Several studies from different populations have reported recurrent and/or founder mutations representing a relevant proportion of BRCA mutation carriers. In Latin America, only few founder mutations have been described. We screened 453 Chilean patients with hereditary breast cancer for mutations in BRCA1 and BRCA2. For recurrent mutations, we genotyped 11 microsatellite markers in BRCA1 and BRCA2 in order to determine a founder effect through haplotype analysis. We found a total of 25 mutations (6 novel) in 71 index patients among which, nine are present exclusively in Chilean patients. Our analysis revealed the presence of nine founder mutations, 4 in BRCA1 and 5 in BRCA2, shared by 2 to 10 unrelated families and spread in different regions of Chile. Our panel contains the highest amount of founder mutations until today and represents the highest percentage (78%) of BRCA1 and BRCA2 mutation carriers. We suggest that the dramatic reduction of Amerindian population due to smallpox and wars with Spanish conquerors, a scarce population increase during 300 years, and the geographic position of Chile constituted a favorable scenario to establish founder genetic markers in our population.

8.
Physiol Plant ; 152(2): 355-66, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24588812

RESUMEN

Silicon (Si) plays important roles in alleviating various abiotic stresses. In rice (Oryza sativa), arsenic (As) is believed to share the Si transport pathway for entry into roots, and Si has been demonstrated to decrease As concentrations. However, the physiological mechanisms through which Si might alleviate As toxicity in plants remain poorly elucidated. We combined detailed gas exchange measurements with chlorophyll fluorescence analysis to examine the effects of Si nutrition on photosynthetic performance in rice plants [a wild-type (WT) cultivar and its lsi1 mutant defective in Si uptake] challenged with As (arsenite). As treatment impaired carbon fixation (particularly in the WT genotype) that was unrelated to photochemical or biochemical limitations but, rather, was largely associated with decreased leaf conductance at the stomata and mesophyll levels. Indeed, regardless of the genotypes, in the plants challenged with As, photosynthetic rates correlated strongly with both stomatal (r(2) = 0.90) and mesophyll (r(2) = 0.95) conductances, and these conductances were, in turn, linearly correlated with each other. The As-related impairments to carbon fixation could be considerably reverted by Si in a time- and genotype-dependent manner. In conclusion, we identified Si nutrition as an important target in an attempt to not only decrease As concentrations but also to ameliorate the photosynthetic performance of rice plants challenged with As.


Asunto(s)
Arsénico/toxicidad , Oryza/fisiología , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/fisiología , Silicio/farmacología , Análisis de Varianza , Dióxido de Carbono/metabolismo , Difusión , Genotipo , Oryza/efectos de los fármacos , Oryza/genética , Hojas de la Planta/efectos de los fármacos , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/fisiología , Factores de Tiempo
9.
Rev Invest Clin ; 65 Suppl 2: s5-27, 2013 Jun.
Artículo en Español | MEDLINE | ID: mdl-24459777

RESUMEN

Non-Hodgkin lymphoma comprises a heterogeneous group of haematological malignancies, classified according to their clinic, anatomic-pathological features and, lately, to their molecular biomarkers. Despite the therapeutic advances, nearly half of the patients will die because of this disease. The new diagnostic tools have been the cornerstone to design recent therapy targets, which must be included in the current treatment guidelines of this sort of neoplasms by means of clinical trials and evidence-based medicine. In the face of poor diagnoses devices in most of the Mexican hospitals, we recommend the present diagnose stratification, and treatment guidelines for non-Hodgkin lymphoma, based on evidence. They include the latest and most innovative therapeutic approaches, as well as specific recommendations for hospitals with limited framework and therapy resources.


Asunto(s)
Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/terapia , Humanos , México
10.
Semina ciênc. agrar ; 31(1): 29-38, 2010. graf, tab
Artículo en Portugués | VETINDEX | ID: biblio-1498565

RESUMEN

The present work had as purpose to evaluate some characteristics of papaya trees (Carica papaya L.), Golden cultivar, obtained trough plant mass selection, regarding plant and fruit quality in the first months of production. The samples were evaluated in a commercial crop at: 0, 20, 40, 70, 130, 180, 230, 260, 280, 310 and 340 days after the planting (DAP) and the first fruits were harvested at 230 DAP. The results showed the low height (199cm in 340 DAP) and low first flowerings heigth (71cm), which is important to facilitate the harvest process. The plants presented good yield with high number of leafs (allowing a great area of fruit cover) and about 60 fruits per plant. The fruits kept similar features to cv. Golden. The fruits fresh weight ranged from 302.4 to 467.5g, which is in the range of the Brazilian market. The pulp thickness was 2.35cm, which is a feature of great economic interest. The pulp thickness showed close relation with climatic factors, and great variations of temperature and precipitation accelerated the pulp loss of thickness.


O presente trabalho teve como objetivo monitorar características vegetativas e dos frutos de mamoeiro (Carica papaya L.), obtidos por seleção massal de plantas da cv. Golden, nos primeiros meses de produção. As amostragens foram realizadas em uma lavoura comercial aos 0, 20, 40, 70, 130, 180, 230, 260, 280, 310 e 340 dias após o plantio (DAP) e os primeiros frutos foram colhidos 230 DAP. Os resultados obtidos evidenciaram baixa altura das plantas (199 cm em 340 DAP) e baixa altura da primeira floração (71 cm), aspectos que facilitam a colheita. As plantas apresentaram boa produtividade, com elevado número de folhas (ampla área de recobrimento dos frutos) e cerca de 60 frutos por planta. Os frutos mantiveram características semelhantes aos da cv. Golden. A massa fresca dos frutos variou de 302,4 a 467,5g, encontrando-se dentro da faixa recomendada para comércio interno. A média da espessura da polpa foi de 2,3 cm, atributo de grande interesse econômico. A firmeza da polpa mostrou uma estreita relação com os fatores climáticos, onde grandes variações de temperatura e pluviosidade aceleraram a perda de firmeza.


Asunto(s)
Carica/crecimiento & desarrollo , Fitomejoramiento , Frutas/crecimiento & desarrollo
11.
Semina Ci. agr. ; 31(1): 29-38, 2010.
Artículo en Portugués | VETINDEX | ID: vti-471073

RESUMEN

The present work had as purpose to evaluate some characteristics of papaya trees (Carica papaya L.), Golden cultivar, obtained trough plant mass selection, regarding plant and fruit quality in the first months of production. The samples were evaluated in a commercial crop at: 0, 20, 40, 70, 130, 180, 230, 260, 280, 310 and 340 days after the planting (DAP) and the first fruits were harvested at 230 DAP. The results showed the low height (199cm in 340 DAP) and low first flowerings heigth (71cm), which is important to facilitate the harvest process. The plants presented good yield with high number of leafs (allowing a great area of fruit cover) and about 60 fruits per plant. The fruits kept similar features to cv. Golden. The fruits fresh weight ranged from 302.4 to 467.5g, which is in the range of the Brazilian market. The pulp thickness was 2.35cm, which is a feature of great economic interest. The pulp thickness showed close relation with climatic factors, and great variations of temperature and precipitation accelerated the pulp loss of thickness.


O presente trabalho teve como objetivo monitorar características vegetativas e dos frutos de mamoeiro (Carica papaya L.), obtidos por seleção massal de plantas da cv. Golden, nos primeiros meses de produção. As amostragens foram realizadas em uma lavoura comercial aos 0, 20, 40, 70, 130, 180, 230, 260, 280, 310 e 340 dias após o plantio (DAP) e os primeiros frutos foram colhidos 230 DAP. Os resultados obtidos evidenciaram baixa altura das plantas (199 cm em 340 DAP) e baixa altura da primeira floração (71 cm), aspectos que facilitam a colheita. As plantas apresentaram boa produtividade, com elevado número de folhas (ampla área de recobrimento dos frutos) e cerca de 60 frutos por planta. Os frutos mantiveram características semelhantes aos da cv. Golden. A massa fresca dos frutos variou de 302,4 a 467,5g, encontrando-se dentro da faixa recomendada para comércio interno. A média da espessura da polpa foi de 2,3 cm, atributo de grande interesse econômico. A firmeza da polpa mostrou uma estreita relação com os fatores climáticos, onde grandes variações de temperatura e pluviosidade aceleraram a perda de firmeza.

12.
Rev. venez. cir ; 59(2): 39-47, jun. 2006. ilus, tab
Artículo en Español | LILACS | ID: lil-465999

RESUMEN

El objetivo es demostrar la eficacia y seguridad de la hemorroidectomía cerrada utilizando clamp de Buie en comparación con la hemorroidectomía abierta (Milligan-Morgan) mediante evaluación de los síntomas a las 24 horas, 1era, 4ta, y 8va semana postoperatoria en pacientes que axudieron al Hospital General del Este "Dr. Domingo Luciani". Agosto 2003-octubre 2004. Como método, estudio prospectivo, explicativo, experimental, aleatorio, simple ciego con muestra de 27 pacientes por grupos. Motivo de consulta más frecuente: dolor ano-rectal, 48 pacientes (88,89 por ciento); la enfermedad hemorroidal predominante: trombosadas 50 pacientes (93 por ciento). En el sangrado postoperatorio a las 24 horas p=0,002 (C.B:4, MM: 16 pac.); el prurito para la cuarta semana P= 0,001 (C.B: 6, M.M: 19). El el dolor fue mayor en la evolución del paciente al que se le aplicó la M.M hasta la cuarta semana (p=0,02; p<0,001; p=0,001). Las complicaciones, sangrado a las 24 horas en ambas técnicas (C.B: 3,7 por ciento y M.M: 7,4 por ciento). La media de la estancia hospitalaria: 1,18 días (P=0,21). Tiempo de cicatrización en C.B tuvo una media: 15,44 y en M.M: 27,55 días (p<0,001). Aplicando la técnica CB, la media de reintegro a sus actividades: 13,70, mientras que en M.M: 21,81 días (p<0.001). La hemorroidectomía cerrada utilizando clamp de Buie es fácil de realizar y se obtienen mejores resultados: menor dolor postoperatorio, sangrado, prurito, cicatrización y reintegro a sus actividades, aportándole mejores beneficios al paciente


Asunto(s)
Humanos , Hemorroides , Técnicas de Diagnóstico Quirúrgico , Venezuela , Cirugía General
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