RESUMEN
The combination of nitric oxide (NO) donors with nanomaterials has emerged as a promising approach to reduce postharvest losses. The encapsulation of NO donors provides protection from rapid degradation and controlled release, enhancing the NO effectiveness in postharvest treatments. Moreover, the application method can also influence postharvest responses. In this study, two application methods were evaluated, spraying and immersion, using S-nitrosoglutathione (GSNO, a NO donor) in free and encapsulated forms on papaya fruit. Our hypothesis was that GSNO encapsulated in chitosan nanoparticles would outperform the free form in delaying fruit senescence. In addition, this study marks the pioneering characterization of chitosan nanoparticles containing GSNO within the framework of a postharvest investigation. Overall, our findings indicate that applying encapsulated GSNO (GSNO-NP-S) through spraying preserves the quality of papaya fruit during storage. This method not only minimizes weight loss, ethylene production, and softening, but also stimulates antioxidant responses, thereby mitigating oxidative damage. Consequently, it stands out as the promising technique for delaying papaya fruit senescence. This innovative approach holds the potential to enhance postharvest practices and advance sustainable agriculture.
Asunto(s)
Carica , Quitosano , Frutas , Donantes de Óxido Nítrico , S-Nitrosoglutatión , Carica/química , Donantes de Óxido Nítrico/farmacología , Donantes de Óxido Nítrico/química , Frutas/química , S-Nitrosoglutatión/farmacología , S-Nitrosoglutatión/química , Quitosano/química , Quitosano/farmacología , Estrés Oxidativo/efectos de los fármacos , Nanopartículas/química , Conservación de Alimentos/métodosRESUMEN
Rivers frequently delimit the geographic ranges of species in the Amazon Basin. These rivers also define the boundaries between genetic clusters within many species, yet river boundaries have been documented to break down in headwater regions where rivers are narrower. To explore the evolutionary implications of headwater contact zones in Amazonia, we examined genetic variation in the Blue-capped Manakin (Lepidothrix coronata), a species previously shown to contain several genetically and phenotypically distinct populations across the western Amazon Basin. We collected restriction site-associated DNA sequence data (RADcap) for 706 individuals and found that spatial patterns of genetic structure indicate several rivers, particularly the Amazon and Ucayali, are dispersal barriers for L. coronata. We also found evidence that genetic connectivity is elevated across several headwater regions, highlighting the importance of headwater gene flow for models of Amazonian diversification. The headwater region of the Ucayali River provided a notable exception to findings of headwater gene flow by harboring non-admixed populations of L. coronata on opposite sides of aâ <â 1-km-wide river channel with a known dynamic history, suggesting that additional prezygotic barriers may be limiting gene flow in this region.
Asunto(s)
Passeriformes , Humanos , Animales , Passeriformes/genética , Brasil , Filogenia , Evolución Biológica , ADN Mitocondrial/genética , RíosRESUMEN
Peridinin is a light-harvesting carotenoid present in phototrophic dinoflagellates and has great potential for new drug applications and cosmetics development. Herein, the effects of irradiance mediated by light-emitting diodes on growth performance, carotenoid and fatty acid profiles, and antioxidant activity of the endosymbiotic dinoflagellate Durusdinium glynnii were investigated. The results demonstrate that D. glynnii is particularly well adapted to low-light conditions; however, it can be high-light-tolerant. In contrast to other light-harvesting carotenoids, the peridinin accumulation in D. glynnii occurred during high-light exposure. The peridinin to chlorophyll-a ratio varied as a function of irradiance, while the peridinin to total carotenoids ratio remained stable. Under optimal irradiance for growth, there was a peak in docosahexaenoic acid (DHA) bioaccumulation. This study contributes to the understanding of the photoprotective role of peridinin in endosymbiont dinoflagellates and highlights the antioxidant activity of peridinin-rich extracts. KEY POINTS: ⢠Peridinin has a protective role against chlorophyll photo-oxidation ⢠High light conditions induce cellular peridinin accumulation ⢠D. glynnii accumulates high amounts of DHA under optimal light supply.
Asunto(s)
Dinoflagelados , Antioxidantes , Carotenoides , Clorofila , Ácidos DocosahexaenoicosRESUMEN
PURPOSE: To investigate the effect of systemic arterial blood pressure (BP) on rates of progressive structural damage over time in glaucoma. DESIGN: Retrospective cohort study. PARTICIPANTS: A total of 7501 eyes of 3976 subjects with glaucoma or suspected of glaucoma followed over time from the Duke Glaucoma Registry. METHODS: Linear mixed models were used to investigate the effects of BP on the rates of retinal nerve fiber layer (RNFL) loss from spectral-domain OCT (SD-OCT) over time. Models were adjusted for intraocular pressure (IOP), gender, race, diagnosis, central corneal thickness (CCT), follow-up time, and baseline disease severity. MAIN OUTCOME MEASURE: Effect of mean arterial pressure (MAP), systolic arterial pressure (SAP), and diastolic arterial pressure (DAP) on rates of RNFL loss over time. RESULTS: A total of 157 291 BP visits, 45 408 IOP visits, and 30 238 SD-OCT visits were included. Mean rate of RNFL change was -0.70 µm/year (95% confidence interval, -0.72 to -0.67 µm/year). In univariable models, MAP, SAP, and DAP during follow-up were not significantly associated with rates of RNFL loss. However, when adjusted for mean IOP during follow-up, each 10 mmHg reduction in mean MAP (-0.06 µm/year; P = 0.007) and mean DAP (-0.08 µm/year; P < 0.001) but not SAP (-0.01 µm/year; P = 0.355) was associated with significantly faster rates of RNFL thickness change over time. The effect of the arterial pressure metrics remained significant after additional adjustment for baseline age, diagnosis, sex, race, follow-up time, disease severity, and corneal thickness. CONCLUSIONS: When adjusted for IOP, lower MAP and DAP during follow-up were significantly associated with faster rates of RNFL loss, suggesting that levels of systemic BP may be a significant factor in glaucoma progression.
Asunto(s)
Presión Sanguínea/fisiología , Glaucoma/diagnóstico , Glaucoma/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Presión Arterial/fisiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Fibras Nerviosas/patología , Hipertensión Ocular/fisiopatología , Sistema de Registros , Células Ganglionares de la Retina/patología , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Tonometría OcularRESUMEN
Collisions with buildings cause up to 1 billion bird fatalities annually in the United States and Canada. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species- and life-history-related variation and correlates of collisions. We addressed these research needs through coordinated collection of data on bird collisions with buildings at sites in the United States (35), Canada (3), and Mexico (2). We collected all carcasses and identified species. After removing records for unidentified carcasses, species lacking distribution-wide population estimates, and species with distributions overlapping fewer than 10 sites, we retained 269 carcasses of 64 species for analysis. We estimated collision vulnerability for 40 bird species with ≥2 fatalities based on their North American population abundance, distribution overlap in study sites, and sampling effort. Of 10 species we identified as most vulnerable to collisions, some have been identified previously (e.g., Black-throated Blue Warbler [Setophaga caerulescens]), whereas others emerged for the first time (e.g., White-breasted Nuthatch [Sitta carolinensis]), possibly because we used a more standardized sampling approach than past studies. Building size and glass area were positively associated with number of collisions for 5 of 8 species with enough observations to analyze independently. Vegetation around buildings influenced collisions for only 1 of those 8 species (Swainson's Thrush [Catharus ustulatus]). Life history predicted collisions; numbers of collisions were greatest for migratory, insectivorous, and woodland-inhabiting species. Our results provide new insight into the species most vulnerable to building collisions, making them potentially in greatest need of conservation attention to reduce collisions and into species- and life-history-related variation and correlates of building collisions, information that can help refine collision management.
Correlaciones de las Colisiones de Aves contra Edificios en Tres Países de América del Norte Resumen Las colisiones contra los edificios causan hasta mil millones de fatalidades de aves al año en los Estados Unidos y en Canadá. Sin embargo, los esfuerzos por reducir estas colisiones se beneficiarían con estudios realizados a grandes escalas espaciales en varios sitios de estudio con métodos estandarizados y considerando las variaciones relacionadas a la historia de vida y a la especie y las correlaciones de las colisiones. Abordamos estas necesidades de investigación por medio de una recolección coordinada de datos sobre las colisiones de aves contra edificios en los Estados Unidos (35), Canadá (3) y México (2). Recolectamos todos los cadáveres y los identificamos hasta especie. Después de retirar los registros de cadáveres no identificados, las especies sin estimaciones poblacionales a nivel distribución y las especies con distribuciones traslapadas en menos de diez sitios, nos quedamos con 269 cadáveres de 64 especies para el análisis. Estimamos la vulnerabilidad a colisiones para 40 especies con ≥2 fatalidades con base en la abundancia poblacional para América del Norte, el traslape de su distribución entre los sitios de estudio y el esfuerzo de muestreo. De las diez especies que identificamos como las más vulnerables a las colisiones, algunas han sido identificadas previamente (Setophaga caerulescens), y otras aparecieron por primera vez (Sitta carolinensis), posiblemente debido a que usamos una estrategia de muestreo más estandarizada que en los estudios previos. El tamaño del edificio y el área del vidrio estuvieron asociados positivamente con el número de colisiones para cinco de ocho especies con suficientes observaciones para ser analizadas independientemente. La vegetación alrededor de los edificios influyó sobre las colisiones solamente para una de esas ocho especies Catharus ustulatus). Las historias de vida pronosticaron las colisiones; el número de colisiones fue mayor para las especies migratorias, insectívoras y aquellas que habitan en las zonas boscosas. Nuestros resultados proporcionan una nueva perspectiva hacia las especies más vulnerables a las colisiones contra edificios, lo que las pone en una necesidad potencialmente mayor de atención conservacionista para reducir estas colisiones y de estudio de las variaciones relacionadas con la especie y la historia de vida y las correlaciones de las colisiones contra edificios, información que puede ayudar a refinar el manejo de colisiones.
Asunto(s)
Conservación de los Recursos Naturales , Pájaros Cantores , Animales , Canadá , México , América del Norte , Estados UnidosRESUMEN
We observed a nocturnal insect swarm aboard the oceanographic ship Cruzeiro do Sul of the Brazilian Navy, while conducting a survey of the Montague guyot (seamount), 389 km distant from the nearest land in the South Atlantic. The insects came from open sea toward the ship from all directions, attracted by the powerful light of the deck. Most insects collided with the hull and fell into the ocean, but we managed to capture and determine 17 (13 Hemiptera of a single species, three Lepidoptera of three species and one Odonata). With one exception, we are certain that none of the specimens caught originated from the ship. The geographic origin, most likely the coast of Brazil, and flight endurance of these insects were inferred using data on wind speed and direction, provided by the crew of the ship, and were reconstructed using Hysplit modeling of air current trajectories.
RESUMEN
Paullinia cupana Kunth var. sorbilis (Mart.) Ducke, the cultivated guarana plant, is native to the Amazon and has been valued for its medicinal, stimulant and energetic properties for centuries. The seeds are the main commercial product of the plant and the source of high amounts of purine alkaloids (caffeine and theobromine) and polyphenols (flavonoids, catechins, and tannins). Proteins involved in the development and maturation of guarana fruits in its native habitat are interesting issues for proteomics. This study presents the proteomic profile of the seed and pericarp of healthy guarana in different maturation stages. Protein contents were higher in the mature seed compared to other stages due to the accumulation of storage proteins - 11S globulins. Proteins selected for identification by mass spectrometry are mostly related to stress responses and defense and this is not unexpected for fast growing and differentiating reproductive tissues.
Asunto(s)
Proteoma , Sapindaceae/genética , Semillas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sapindaceae/crecimiento & desarrollo , Semillas/crecimiento & desarrolloAsunto(s)
Colestasis/terapia , Endoscopía del Sistema Digestivo/métodos , Trasplante de Hígado , Complicaciones Posoperatorias/terapia , Brasil , Colestasis/diagnóstico por imagen , Colestasis/economía , Colestasis/etiología , Análisis Costo-Beneficio , Endoscopía del Sistema Digestivo/economía , Endoscopía del Sistema Digestivo/instrumentación , Humanos , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/economíaRESUMEN
INTRODUCTION: SIOPEN INES protocol yielded excellent 5-year survival rates for MYCN-non-amplified metastatic neuroblastoma. Patients deemed ineligible due to lack or delay of MYCN status or late registration were treated, but not included in the study. Our goal was to analyse survival at 10 years among the whole population. MATERIALS AND METHODS: Italian and Spanish metastatic INES patients' data are reported. SPSS 20.0 was used for statistical analysis. RESULTS: Among 98 infants, 27 had events and 19 died, while 79 were disease free. Five- and 10-year event-free survival (EFS) were 73 and 70 %, and overall survival (OS) was 81 and 74 %, respectively. MYCN status was significant for EFS, but not for OS in multivariate analysis. CONCLUSIONS: The survival rates of patients who complied with all the inclusion criteria for INES trials are higher compared to those that included also not registered patients. Five-year EFS and OS for INES 99.2 were 87.8 and 95.7 %, while our stage 4s population obtained 78 and 87 %. Concerning 99.3, 5-year EFS and OS were 86.7 and 95.6 %, while for stage 4 we registered 61 and 68 %. MYCN amplification had a strong impact on prognosis and therefore we consider it unacceptable that many patients were not studied for MYCN and probably inadequately treated. Ten-year survival rates were shown to decrease: EFS from 73 to 70 % and OS from 81 to 74 %, indicating a risk of late events, particularly in stage 4s. Population-based registries like European ENCCA WP 11-task 11 will possibly clarify these data.
Asunto(s)
Biomarcadores de Tumor/genética , Ensayos Clínicos como Asunto , Amplificación de Genes , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/mortalidad , Niño , Preescolar , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estadificación de Neoplasias , Neuroblastoma/genética , Neuroblastoma/secundario , Neuroblastoma/terapia , Pronóstico , Tasa de SupervivenciaRESUMEN
Fusarium oxysporum f. sp cubense (Foc), the causal agent of Panama disease, is responsible for economic losses in banana crops worldwide. The identification of genes that effectively act on pathogenicity and/or virulence may contribute to the development of different strategies for disease control and the production of resistant plants. The objective of the current study was to analyze the importance of SGE1 gene expression in Foc virulence through post-transcriptional silencing using a double-stranded RNA hairpin. Thirteen transformants were selected based on different morphological characteristics, and sporulation in these transformants was significantly reduced by approximately 95% (P < 0.05) compared to that of the wild-type strain. The relative SGE1 expression levels in the transformant strains were reduced by 27 to 47% compared to those in the wild-type strain. A pathogenicity analysis revealed that the transformants were able to reach the rhizomes and pseudostems of the inoculated banana plants. However, the transformants induced initial disease symptoms in the banana plants approximately 10 days later than that by the wild-type Foc, and initial disease symptoms persisted even at 45 days after inoculation. These results indicate that the SGE1 gene is directly involved in the virulence of Foc. Therefore, SGE1 may be a potential candidate for host-induced gene silencing in banana plants.
Asunto(s)
Proteínas Fúngicas/genética , Fusarium/genética , Proteínas Fúngicas/metabolismo , Fusarium/patogenicidad , Interferencia de ARN , ARN Interferente Pequeño/genética , Virulencia/genéticaRESUMEN
House geckos in the genus Hemidactylus are highly successful colonizers of regions beyond their native range, with colonization often resulting in displacement of native gecko species through competitive interactions for daytime refuge (crevices) and prey resources. We report on data collected from nighttime surveys undertaken in April-May 2014 on Barbados, West Indies, that focused on the distribution and abundance of the endemic Barbados leaf-toed gecko (Phyllodactylus pulcher) and the introduced tropical house gecko (Hemidactylus mabouia) along unlit coastal walls and among boulders in the grounds of a hotel resort. In contrast to patterns of displacement of native species by H. mabouia seen elsewhere, P. pulcher was more abundant than H. mabouia on coastal walls, whereas the latter was found in greater numbers using boulders at this site. Walls and boulders differed with regard to availability of diurnal refugia suitable for geckos, with the walls having high frequency of small crevices with openings <20 mm, and boulders offering very little cover other than the underside of the boulder itself. To investigate whether this niche separation was a result of differences in diurnal refuge use between the species, we conducted experimental trials in which geckos were allowed to select between refugia with different characteristics. Both species selected for narrower and warmer refugia, and refugia that had been previously occupied by the other species. These shared preferences for refugia type suggest that other factors underlie the niche separation observed in the field. In supporting high densities of P. pulcher, coastal walls could offer important secondary habitat by augmenting the natural cliff side habitat of this endemic gecko, a finding that could be exploited for the conservation of this candidate species for Critically Endangered classification.
Asunto(s)
Conducta Animal , Ecosistema , Lagartos/fisiología , Animales , Barbados , Conducta de Elección , Conducta Competitiva , Femenino , Especies Introducidas , Masculino , Densidad de PoblaciónRESUMEN
AIM: To review results of endoscopic treatment for anastomotic biliary strictures after orthotopic liver transplantation (OLT) during an 8-year period. METHODS: This is a retrospective review of all endoscopic retrograde cholangiopancreatographys (ERCPs) performed between May 2006 and June 2014 in deceased OLT recipients with anastomotic stricture at a tertiary care hospital. Patients were divided into 2 groups, according to the type of stent used (multiple plastic or covered self-expandable metal stents), which was chose on a case-by-case basis and their characteristics. The primary outcome was anastomotic stricture resolution rate determined if there was no more than a minimum waist at cholangiography and a 10 mm balloon could easily pass through the anastomosis with no need for further intervention after final stent removal. Secondary outcomes were technical success rate, number or ERCPs required per patient, number of stents placed, stent indwelling, stricture recurrence rate and therapy for recurrent anastomotic biliary stricture (AS). Stricture recurrence was defined as clinical laboratorial and/or imaging evidence of obstruction at the anastomosis level, after it was considered completely treated, requiring subsequent interventional procedure. RESULTS: A total of 195 post-OLT patients were assessed for eligibility. One hundred and sixty-four (164) patients were diagnosed with anastomotic biliary stricture. ERCP was successfully performed in 157/164 (95.7%) patients with AS, that were treated with either multiple plastic (n = 109) or metallic billiary stents (n = 48). Mean treatment duration, number of procedures and stents required were lower in the metal stent group. Acute pancreatitis was the most common procedure related complication, occurring in 17.1% in the covered self-expandable metal stents (cSEMS) and 4.1% in the multiple plastic stent (MPS) group. Migration was the most frequent stent related complication, observed in 4.3% and 5.5% (cSEMS and MPS respectively). Stricture resolution was achieved in 86.8% in the cSEMS group and in 91% in MPS group. Stricture recurrence after a median follow up of 20 mo was observed in 10 (30.3%) patients in the cSEMS and 7 (7.7%) in the plastic stent group, a statistically significant difference (P = 0.0017). Successful stricture resolution after secondary treatment was achieved in 66.6% and 62.5% of patients respectively in the cSEMS and plastic stents groups. CONCLUSION: Multiple plastic stents are currently the first treatment option for AS in patients with duct-to-duct anastomosis. cSEMS was associated with increased pancreatitis risk and higher recurrence rate.
RESUMEN
INTRODUCTION: Adequate sedation is one of the cornerstones of good quality gastrointestinal endoscopy (GIE). Propofol sedation has increased significantly but there has been much debate over whether it can be administered by endoscopists. The aim of this prospective trial was to compare nonanesthesiologist-administered propofol (NAAP) and monitored anesthesia care (MAC). METHODS: A total of 2000 outpatients undergoing GIE at Hospital Albert Einstein (São Paulo, Brazil), a tertiary-care private hospital, were divided into two matched groups: NAAP (nâ=â1000) and MAC (nâ=â1000). In NAAP, propofol doses were determined by the endoscopist. A second physician stayed in the room during the entire procedure, according to local regulations. In MAC, the anesthesiologist administered propofol. RESULTS: In total, 1427 patients (71.3â%) were ASA (American Society of Anesthesiologists) class I and 573 were ASA class II. In NAAP, patients received more propofolâ+âfentanyl (61.1â% vs. 50.5â%; Pâ<â0.05) and there were fewer cases of deep sedation (44.7â% vs. 66.1â%; Pâ<â0.05). Hypoxemia rates were similar (12.8â% for NAAP and 11.2â% for MAC; Pâ=â0.3) but these reverted more rapidly in MAC (4.22 seconds vs. 7.26 seconds; Pâ<â0.05). Agitation was more frequent in MAC (14.0â% vs. 5.6â%; Pâ<â0.05). No later complications were observed. Patient satisfaction was very high and similar in both groups. CONCLUSION: In this setting, NAAP was as safe and effective as MAC for healthy patients undergoing GIE. Clinical trial ref. no.: U1111-1134-4430.
RESUMEN
Guarana has great agricultural potential and is largely used therapeutically and in the production of non-alcoholic energy drinks. Genomic and proteomic studies are crucial to identify proteins that play central roles in the maintenance and viability of fruits, as well as to identify proteins related to the main metabolic pathways. However, the success of any protein analysis starts with the protein extract preparation, which needs to offer an extract that is free of contaminants. This study aimed to evaluate different extraction methods to obtain high-quantity and high-quality extracts that are compatible with analysis by 2-dimensional electrophoresis and tandem mass spectrometry protein identification. Three different methods were tested: trichloroacetic acid (TCA)/acetone, sodium dodecyl sulfate (SDS)/phenol, and polyvinylpolypyrrolidone (PVPP)/SDS/phenol. The extract obtained from the TCA/acetone precipitation presented low solubility and contamination with lipids and carbohydrates. On the other hand, the quality of the extract gradually improved after using phenol and PVPP/phenol, enabling a yield up to 2 mg/g macerated tissues and the detection of 457 spots by 2-dimensional electrophoresis. The effectiveness of the procedure used was validated by identification of 10 randomly selected proteins by mass spectrometry. The procedure described here can be a starting point for applications using tissues of other organs of guarana or tissues of species that are similar to guarana.
Asunto(s)
Paullinia/química , Proteínas de Plantas/metabolismo , Proteómica , Electroforesis en Gel Bidimensional , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemAsunto(s)
Adenocarcinoma Mucinoso/diagnóstico , Colestasis/terapia , Ictericia Obstructiva/terapia , Neoplasias Hepáticas/secundario , Cuidados Paliativos , Neoplasias Pancreáticas/diagnóstico , Adenocarcinoma Mucinoso/complicaciones , Adenocarcinoma Mucinoso/secundario , Anciano , Colestasis/etiología , Endoscopía del Sistema Digestivo , Humanos , Ictericia Obstructiva/etiología , Neoplasias Hepáticas/diagnóstico por imagen , Metástasis Linfática , Masculino , Conductos Pancreáticos/anomalías , Neoplasias Pancreáticas/complicaciones , Cintigrafía , StentsRESUMEN
The sloth's giant tick Amblyomma varium Koch, which is a neotropical species that inhabits tropical rainforests, is the largest tick reported to date. The adult stage of this tick parasitizes mammals from the families Bradypodidae and Magalonychidae (Xenarthra) nearly exclusively. This study aimed to describe morphological and histological features of the reproductive system and the oocyte maturation process of this tick species. The ovary of A. varium is a long single tubular organ that is horseshoe-shaped, winding and arranged in the posterior part of the body. Two oviducts are connected to the ovary on each side; these thicken at certain region forming the uterus (common oviduct), followed by a muscular connecting tube, vagina and genital aperture. A large number of oocytes at different stages of development are attached to the ovary wall by the pedicel, as they reach maturity they are released into the ovary lumen and from there to the genital aperture. These oocytes develop simultaneously and asynchronically along the ovary. Amblyomma varium oocytes were classified into five development stages (i.e., I-V), and specific characteristics were observed; the processes of yolk and chorion deposition begin early in oocytes stage II, and oocytes V exhibit a very thick chorion and eggs of a large size. These characteristics are likely adaptations that enhance the survival and the reproductive success of this extremely host-specific tick, which is limited to a particular environment.
Asunto(s)
Ixodidae/anatomía & histología , Perezosos/parasitología , Animales , Brasil , Femenino , Histocitoquímica , Ixodidae/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Oocitos/ultraestructura , Ovario/anatomía & histologíaRESUMEN
Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry. The total number of spots detected was 1985; the number ranged from 99 to 380 in each assay. The proteins that were identified spectrometrically were categorized as chaperones, proteins expressed exclusively under heat stress, enzymes involved in the respiratory and fermentation cycles, ribosomal proteins, and proteins related to transport and secretion. Controlling inverted repeat of chaperone expression and inverted repeat DNA binding sequences, as well as regions recognized by sigma factor 32, elements involved in the genetic regulation of the bacterial stress response, were identified in the promoter regions of several of the genes coding proteins, involved in the C. violaceum stress response. We found that 30 °C is the optimal growth temperature for C. violaceum, whereas 25, 35, and 40 °C are stressful temperatures that trigger the expression of chaperones, superoxide dismutase, a probable small heat shock protein, a probable phasing, ferrichrome-iron receptor protein, elongation factor P, and an ornithine carbamoyltransferase catabolite. This information improves our comprehension of the mechanisms involved in stress adaptation by C. violaceum.
Asunto(s)
Adaptación Biológica , Proteínas Bacterianas/metabolismo , Chromobacterium/metabolismo , Proteómica , Estrés Fisiológico , Temperatura , Adaptación Biológica/genética , Proteínas Bacterianas/genética , Respiración de la Célula , Chromobacterium/genética , Chromobacterium/crecimiento & desarrollo , Fermentación , Regulación Bacteriana de la Expresión Génica , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Sistemas de Lectura Abierta , Regiones Promotoras Genéticas , Proteómica/métodos , Estrés Fisiológico/genéticaRESUMEN
BACKGROUND: The scarcity of information on the immature stages of sand flies and their preferred breeding sites has resulted in the focus of vectorial control on the adult stage using residual insecticide house-spraying. This strategy, along with the treatment of human cases and the euthanasia of infected dogs, has proven inefficient and visceral leishmaniasis continues to expand in Brazil. Identifying the breeding sites of sand flies is essential to the understanding of the vector's population dynamic and could be used to develop novel control strategies. METHODOLOGY/PRINCIPAL FINDING: In the present study, an intensive search for the breeding sites of Lutzomyia longipalpis was conducted in urban and peri-urban areas of two municipalities, Promissão and Dracena, which are endemic for visceral leishmaniasis in São Paulo State, Brazil. During an exploratory period, a total of 962 soil emergence traps were used to investigate possible peridomiciliary breeding site microhabitats such as: leaf litter under tree, chicken sheds, other animal sheds and uncovered debris. A total of 160 sand flies were collected and 148 (92.5%) were L. longipalpis. In Promissão the proportion of chicken sheds positive was significantly higher than in leaf litter under trees. Chicken shed microhabitats presented the highest density of L. longipalpis in both municipalities: 17.29 and 5.71 individuals per square meter sampled in Promissão and Dracena respectively. A contagious spatial distribution pattern of L. longipalpis was identified in the emergence traps located in the chicken sheds. CONCLUSION: The results indicate that chicken sheds are the preferential breeding site for L. longipalpis in the present study areas. Thus, control measures targeting the immature stages in chicken sheds could have a great effect on reducing the number of adult flies and consequently the transmission rate of Leishmania (Leishmania) infantum chagasi.
Asunto(s)
Vivienda para Animales , Insectos Vectores , Psychodidae/crecimiento & desarrollo , Animales , Brasil/epidemiología , Pollos , Enfermedades Endémicas , Femenino , Humanos , Larva/crecimiento & desarrollo , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/transmisión , Masculino , Población UrbanaRESUMEN
Cryopreservation of mesenchymal stem cells from amniotic fluid is of clinical importance, as these cells can be harvested during the prenatal period and stored for use in treatments. We examined the behavior of mesenchymal stem cells from human amniotic fluid in culture that had been subjected to cryopreservation. We assessed chromosomal stability through karyotype analysis, determined whether multipotent capacity (differentiation into adipogenic, chondrogenic, and osteogenic cells) is maintained, and analyzed SOX2 and NANOG expression after thawing. Five amniotic fluid samples were cryopreserved for 150 days. No chromosomal aberrations were observed. The expression levels of NANOG and SOX2 also were quite similar before and after cryopreservation. Capacity for differentiation into adipogenic, chondrogenic, and osteogenic tissues also remained the same. We conclude that cryopreservation of amniotic fluid does not alter karyotype, NANOG/SOX2 gene expression, or multipotent capacity of stem cells that have been collected from amniotic fluid during pregnancy.