RESUMEN
Breast cancer is the most common cancer in women. Although chemotherapy is still broadly used in its treatment, adverse effects remain a challenge. In this scenario, aptamers emerge as a promising alternative for theranostic applications. Studies using breast cancer cell lines provide useful information in laboratory and preclinical investigations, most of which use cell lines established from metastatic sites. However, these cell lines correspond to cell populations of the late stage of tumor progression. On the other hand, studies using breast cancer cells established from primary sites make it possible to search for new theranostic approaches in the early stages of the disease. Therefore, this work aimed to select RNA aptamers internalized by MGSO-3 cells, a human breast cancer cell line, derived from a primary site previously established in our laboratory. Using the Cell-Internalization SELEX method, we have selected two candidate aptamers (ApBC1 and ApBC2). We evaluated their internalization efficiencies, specificities, cellular localization by Reverse Transcription-qPCR (RT-qPCR) and confocal microscopy assays. The results suggest that both aptamers were efficiently internalized by human breast cancer cells, MACL-1, MDA-MB-231, and especially by MGSO-3 cells. Furthermore, both aptamers could effectively distinguish human breast cancer cells derived from normal human mammary cell (MCF 10A) and prostate cancer cell (PC3) lines. Therefore, ApBC1 and ApBC2 could be promising candidate molecules for theranostic applications, even in the early stages of tumor progression.
Asunto(s)
Aptámeros de Nucleótidos , Neoplasias de la Mama , Humanos , Femenino , Aptámeros de Nucleótidos/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/tratamiento farmacológico , Células MCF-7 , Línea Celular Tumoral , Técnica SELEX de Producción de AptámerosRESUMEN
Spinocerebellar ataxia 19 (SCA19) represents a rare autosomal dominant genetic disorder resulting in progressive ataxia and cerebellar atrophy. SCA19 is caused by variants in the KCND3 gene, which encodes a voltage-gated potassium channel subunit essential for cerebellar Purkinje cell function. We describe six cases from Chile and Mexico, representing the largest report on SCA19 in Latin America. These cases encompass a range of clinical presentations, highlighting the phenotypic variability within SCA19 from an early-onset, severe disease to a late-onset, slowly progressive condition with normal lifespan. While some patients present with pure ataxia, others also show cognitive impairment, dystonia, and other neurological symptoms. The correlations between specific KCND3 variants and phenotypic outcomes are complex and warrant further investigation. As the genomic landscape of spinocerebellar ataxias evolves, comprehensive genetic testing is becoming pivotal in improving diagnostic accuracy. This study contributes to a better understanding of the clinical spectrum of SCA19, laying the groundwork for further genotype-phenotype correlations and functional studies to elucidate the underlying pathophysiology.
Asunto(s)
Fenotipo , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , México/epidemiología , Chile/epidemiología , Anciano , Degeneraciones Espinocerebelosas/genética , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/epidemiologíaRESUMEN
Little is known about access of rare disease carriers to health care. To increase this knowledge, the Pan American Hereditary Ataxia Network (PAHAN) conducted an exploratory survey about care for hereditary ataxias in American continents and the Caribbean. A questionnaire was sent to health professionals about the hereditary ataxias identified; access to care; and local teaching and research. The number of ataxics under current care per 100,000 inhabitants was subtracted from the expected overall prevalence of 6/100,000, to estimate the prevalence of uncovered ataxic patients. Local Human Development Indexes (HDI) were used to measure socio-economic factors. Twenty-six sites participated. Twelve sites had very high, 13 had high, and one site had medium HDI. Participants reported on 2239 and 602 patients with spinocerebellar ataxias and recessive forms under current care. The number of patients under current care per inhabitants varied between 0.14 and 12/100,000. The estimated prevalence of uncovered ataxic patients was inversely proportional to HDIs (rho = 0.665, p = 0.003). Access to diagnosis, pre-symptomatic tests, and rehabilitation were associated with HDIs. More and better molecular diagnostic tools, protocols and guidelines, and professional training for ataxia care were the top priorities common to all respondents. Evidence of inequalities was confirmed. Lower HDIs were associated with high potential numbers of uncovered ataxic subjects, and with lack of molecular diagnosis, pre-symptomatic testing, and rehabilitation. More and better diagnostic tools, guidelines, and professional training were priorities to all sites. PAHAN consortium might help with the last two tasks.
Asunto(s)
Ataxia Cerebelosa , Ataxias Espinocerebelosas , Degeneraciones Espinocerebelosas , Humanos , Ataxia , Degeneraciones Espinocerebelosas/epidemiología , Ataxias Espinocerebelosas/diagnóstico , Ataxias Espinocerebelosas/epidemiología , Ataxias Espinocerebelosas/genética , Región del Caribe/epidemiologíaRESUMEN
Huanglongbing (HLB), formerly known as greening, is a bacterial disease restricted to some Asian and African regions until two decades ago. Nowadays, associated bacteria and their vectors have spread to almost all citrus-producing regions, and it is currently considered the most devastating citrus disease. HLB management can be approached in terms of prevention, limiting or avoiding pathogen and associated vectors to reach an area, or in terms of control, trying to reduce the impact of the disease by adopting different cultural strategies depending on infestation/infection levels. In both cases, control of psyllid populations is currently the best way to stop HLB spread. Best cultural actions (CHMAs, TPS system) to attain this goal and, thus, able to limit HLB spread, and ongoing research in this regard is summarized in this review.
Asunto(s)
Citrus , Hemípteros , Rhizobiaceae , Animales , Enfermedades de las Plantas/prevención & controlRESUMEN
Autosomal recessive cerebellar ataxia type 1 (ARCA-1) or spinocerebellar ataxia autosomal recessive type 8 (SCAR8) is a slowly progressive neurodegenerative disorder that occurs due to mutations in the spectrin repeat containing nuclear envelope protein 1 (SYNE1) gene. Previously considered a rare cause of ARCA, related to French-Canadian patients from Beauce, Quebec, Canada, SYNE1 ataxia is now known to be of worldwide distribution. We present the case report of a 54-year-old male patient with the genetic diagnosis of SYNE1 ataxia, presenting with a SYNE1 gene mutation never described in Chilean population before.
Asunto(s)
Ataxia Cerebelosa , Canadá , Ataxia Cerebelosa/diagnóstico por imagen , Ataxia Cerebelosa/genética , Proteínas del Citoesqueleto/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genéticaRESUMEN
Human adipose-derived stromal/stem cells (ASC) have immunomodulatory properties and the potential to differentiate into several cell lines, important for application in regenerative medicine. However, the contamination with dermal fibroblasts (FIB) can impair the beneficial effects of ASC in cell therapy. It is then essential to develop new strategies that contribute to the distinction between these two cell types. In this study, we performed functional assays, high-throughput RNA sequencing (RNA-Seq) and quantitative PCR (qPCR) to find new markers that can distinguish ASC and FIB. We showed that ASC have adipogenic and osteogenic differentiation capacity and alkaline phosphatase activity, not observed in FIB. Gene expression variation analysis identified more than 2000 differentially expressed genes (DEG) between these two cell types. We validated 16 genes present in the list of DEG, including the alkaline phosphatase gene (ALPL). In conclusion, we showed that ASC and FIB have distinct biological properties as demonstrated by alkaline phosphatase activity and differentiation capacity, besides having different gene expression profiles. SIGNIFICANCE OF THE STUDY: Although many differences between stromal stem cells derived from human adipose tissue (ASC) and human dermal fibroblasts (FIB) are described, it is still difficult to find specific markers to differentiate them. This problem can interfere with the therapeutic use of ASC. This work aimed to find new markers to differentiate these two cell populations. Our findings suggest that these cells can be distinguished by biological and molecular characteristics, such as adipogenic and osteogenic differentiation, alkaline phosphatase activity and differential gene expression profiles. The DEG were related to the regulation of the cell cycle, development process, structural organization of the cell and synthesis of the extracellular matrix. This study helps to find new cellular markers to distinguish the two populations and to better understand the properties of these cells, which can improve cell therapy.
Asunto(s)
Tejido Adiposo/metabolismo , Dermis/metabolismo , Fibroblastos/metabolismo , RNA-Seq , Células Madre/metabolismo , Tejido Adiposo/citología , Dermis/citología , Fibroblastos/citología , Humanos , Especificidad de Órganos , Células Madre/citología , Células del Estroma/citología , Células del Estroma/metabolismoRESUMEN
Calcium (Ca2+) signaling within the cell nucleus regulates specific cellular events such as gene transcription and cell proliferation. Nuclear and cytosolic Ca2+ levels can be independently regulated, and nuclear translocation of receptor tyrosine kinases (RTKs) is one way to locally activate signaling cascades within the nucleus. Nuclear RTKs, including the epidermal growth factor receptor (EGFR), are important for processes such as transcriptional regulation, DNA-damage repair, and cancer therapy resistance. RTKs can hydrolyze phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) within the nucleus, leading to Ca2+ release from the nucleoplasmic reticulum by inositol 1,4,5-trisphosphate receptors. PI(4,5)P2 hydrolysis is mediated by phospholipase C (PLC). However, it is unknown which nuclear PLC isoform is triggered by EGFR. Here, using subcellular fractionation, immunoblotting and fluorescence, siRNA-based gene knockdowns, and FRET-based biosensor reporter assays, we investigated the role of PLCδ4 in epidermal growth factor (EGF)-induced nuclear Ca2+ signaling and downstream events. We found that EGF-induced Ca2+ signals are inhibited when translocation of EGFR is impaired. Nuclear Ca2+ signals also were reduced by selectively buffering inositol 1,4,5-trisphosphate (InsP3) within the nucleus. EGF induced hydrolysis of nuclear PI(4,5)P2 by the intranuclear PLCδ4, rather than by PLCγ1. Moreover, protein kinase C, a downstream target of EGF, was active in the nucleus of stimulated cells. Furthermore, PLCδ4 and InsP3 modulated cell cycle progression by regulating the expression of cyclins A and B1. These results provide evidence that EGF-induced nuclear signaling is mediated by nuclear PLCδ4 and suggest new therapeutic targets to modulate the proliferative effects of this growth factor.
Asunto(s)
Señalización del Calcio/efectos de los fármacos , Núcleo Celular/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Fosfolipasa C delta/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Cadenas Pesadas de Clatrina/antagonistas & inhibidores , Cadenas Pesadas de Clatrina/genética , Cadenas Pesadas de Clatrina/metabolismo , Ciclina A/metabolismo , Ciclina B1/metabolismo , Receptores ErbB/metabolismo , Humanos , Hidrólisis , Inositol 1,4,5-Trifosfato/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipasa C delta/antagonistas & inhibidores , Fosfolipasa C delta/genética , Fosfolipasa C gamma/antagonistas & inhibidores , Fosfolipasa C gamma/genética , Fosfolipasa C gamma/metabolismo , Proteína Quinasa C/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismoRESUMEN
Nuclear Epidermal Growth Factor Receptor (EGFR) has been associated with worse prognosis and treatment resistance for several cancer types. After Epidermal Growth Factor (EGF) binding, the ligand-receptor complex can translocate to the nucleus where it functions in oncological processes. By three-dimensional quantification analysis of super-resolution microscopy images, we verified the translocation kinetics of fluorescent conjugated EGF to the nucleus in two mesenchymal cell types: human adipose tissue-derived stem cells (hASC) and SK-HEP-1 tumor cells. The number of EGF clusters in the nucleus does not change after 10â¯min of stimulation with EGF in both cells. The total volume occupied by EGF clusters in the nucleus of hASC also does not change after 10â¯min of stimulation with EGF. However, the total volume of EGF clusters increases only after 20â¯min in SK-HEP-1 cells nuclei. In these cells the nuclear volume occupied by EGF is 3.2 times higher than in hASC after 20â¯min of stimulation, indicating that translocation kinetics of EGF differs between these two cell types. After stimulation, EGF clusters assemble in larger clusters in the cell nucleus in both cell types, which suggests specific sub-nuclear localizations of the receptor. Super-resolution microscopy images show that EGF clusters are widespread in the nucleoplasm, and can be localized in nuclear envelope invaginations, and in the nucleoli. The quantitative study of EGF-EGFR complex translocation to the nucleus may help to unravel its roles in health and pathological conditions, such as cancer.
Asunto(s)
Núcleo Celular/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Células Madre Mesenquimatosas/metabolismo , Tejido Adiposo/citología , Línea Celular Tumoral , Linaje de la Célula , Factor de Crecimiento Epidérmico/química , Colorantes Fluorescentes/química , Humanos , Cinética , Células Madre Mesenquimatosas/citología , Membrana Nuclear/metabolismo , Transporte de ProteínasRESUMEN
BACKGROUND: Mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. However, selection over mitochondrial DNA (mtDNA) genes has usually been evaluated at the population level. We sequenced by NGS 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distributed from the equator to Antarctica. Signatures of selection of 13 mitochondrial protein-coding genes were evaluated by comparing among species within and among genera (Spheniscus, Pygoscelis, Eudyptula, Eudyptes and Aptenodytes). The genetic data were correlated with environmental data obtained through remote sensing (sea surface temperature [SST], chlorophyll levels [Chl] and a combination of SST and Chl [COM]) through the distribution of these species. RESULTS: We identified the complete mtDNA genomes of several penguin species, including ND6 and 8 tRNAs on the light strand and 12 protein coding genes, 14 tRNAs and two rRNAs positioned on the heavy strand. The highest diversity was found in NADH dehydrogenase genes and the lowest in COX genes. The lowest evolutionary divergence among species was between Humboldt (Spheniscus humboldti) and Galapagos (S. mendiculus) penguins (0.004), while the highest was observed between little penguin (Eudyptula minor) and Adélie penguin (Pygoscelis adeliae) (0.097). We identified a signature of purifying selection (Ka/Ks < 1) across the mitochondrial genome, which is consistent with the hypothesis that purifying selection is constraining mitogenome evolution to maintain Oxidative phosphorylation (OXPHOS) proteins and functionality. Pairwise species maximum-likelihood analyses of selection at codon sites suggest positive selection has occurred on ATP8 (Fixed-Effects Likelihood, FEL) and ND4 (Single Likelihood Ancestral Counting, SLAC) in all penguins. In contrast, COX1 had a signature of strong negative selection. ND4 Ka/Ks ratios were highly correlated with SST (Mantel, p-value: 0.0001; GLM, p-value: 0.00001) and thus may be related to climate adaptation throughout penguin speciation. CONCLUSIONS: These results identify mtDNA candidate genes under selection which could be involved in broad-scale adaptations of penguins to their environment. Such knowledge may be particularly useful for developing predictive models of how these species may respond to severe climatic changes in the future.
Asunto(s)
Evolución Molecular , Genoma Mitocondrial , Selección Genética , Spheniscidae/genética , Animales , ADN Mitocondrial/química , Interacción Gen-Ambiente , GenómicaRESUMEN
The development of a myriad of nanoparticles types has opened new possibilities for the diagnostics and treatment of many diseases, especially for cancer. However, most of the researches done so far do not focus on the protection of normal cells surrounding a tumor from irradiation bystander effects that might lead to cancer recurrence. Gap-junctions are known to be involved in this process, which leads to genomic instability of neighboring normal cells, and flufenamic acid (FFA) is included in a new group of gap-junction blockers recently discovered. The present work explores the use of mesoporous silica nanoparticles MCM-41 functionalized with 3-Aminopropyltriethoxysilane (APTES) for anchoring the flufenamic acid for its prolonged and controlled release and protection from radiation bystander effects. MCM-41 and functionalized samples were structurally and chemically characterized with multiple techniques. The biocompatibility of all samples was tested in a live/dead assay performed in cultured MRC-5 and HeLa cells. HeLa cells cultured were exposed to 50 Gy of gamma-rays and the media transferred to fibroblast cells cultured separately. Our results show that MCM-41 and functionalized samples have high biocompatibility with MCR-5 and HeLa cells, and most importantly, the FFA delivered by these NPs was able to halt apoptosis, one of main bystander effects.
Asunto(s)
Efecto Espectador/efectos de la radiación , Ácido Flufenámico/química , Ácido Flufenámico/farmacología , Nanopartículas/química , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Efecto Espectador/efectos de los fármacos , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/efectos de la radiación , Rayos gamma/efectos adversos , Humanos , Ensayo de Materiales , Microscopía Electrónica de RastreoRESUMEN
Tissue bioengineering development is a global concern and different materials are studied and created to be safe, effective and with low cost. Nile Tilapia skin had shown its biological potential as covers for the burn wound. This study evaluates the tilapia skin histological, collagen properties and tensiometric resistance, after treatment by different sterilization methods. Tilapia skin samples were submitted to two sterilization processes: (1) chemical, which consisted in two 2% chlorhexidin baths, followed by sequential baths in increasing glycerol concentrations; and (2) radiation, when glycerolized skin samples were submitted to gamma radiation at 25, 30 and 50 kGy. Microscopic analyzes were performed through Haematoxylin-eosin and Picrosirius Red under polarized light. For tensiometric analysis, traction tests were performed. Glycerol treated skin presented a discrete collagen fibers disorganization within the deep dermis, while irradiated skin did not show any additional change. Throughout the steps of chemical sterilization, there was a higher proportion of collagen with red/yellow birefringence (type I) in the skin samples up to the first bath in chlorhexidin, when compared to samples after the first two glycerol baths (P < 0.005). However, there was no difference in relation to total collagen between groups. In irradiated skin, there was a larger total collagen preservation when using until 30 kGy (P < 0.005). Tensiometric evaluation did not show significant differences in relation to maximum load in the groups studied. We concluded that chemical and radiation (25 and 30 kGy) are efficient methods to sterilize Nile Tilapia skin without altering its microscopic or tensiometric characteristics.
Asunto(s)
Cíclidos/microbiología , Colágeno/análisis , Piel/microbiología , Piel/ultraestructura , Esterilización/métodos , Animales , Quemaduras/terapia , Rayos gamma , Piel/efectos de los fármacos , Piel/efectos de la radiación , Ingeniería de TejidosRESUMEN
Much emphasis has been given to the deafness of Ludwig van Beethoven and its potential causes. However, when analyzing several symptoms reported by himself throughout his life in many letters and his final illness, a common etiology emerges. This article reports the medical history of this artist, based on authoritative scientific sources.
Asunto(s)
Sordera/historia , Personajes , Enfermedades del Sistema Inmune/historia , Enfermedades Inflamatorias del Intestino/historia , Música/historia , Sordera/etiología , Alemania , Historia del Siglo XVIII , Historia del Siglo XIX , Humanos , Enfermedades del Sistema Inmune/etiología , Enfermedades Inflamatorias del Intestino/complicaciones , Cirrosis Hepática/historiaRESUMEN
The renewable energy sector is growing at a rapid pace in northern Chile and the solar energy potential is one of the best worldwide. Therefore, many types of solar power plant facilities are being built to take advantage of this renewable energy resource. Solar energy is considered a clean source of energy, but there are potential environmental effects of solar technology, such as landscape fragmentation, extinction of local biota, microclimate changes, among others. To be able to minimize environmental impacts of solar power plants, it is important to know what kind of environmental conditions solar power plants create. This study provides information about abiotic and biotic conditions in the vicinity of photovoltaic solar power plants. Herein, the influence of these power plants as drivers of new microclimate conditions and arthropods diversity composition in the Atacama Desert was evaluated. Microclimatic conditions between panel mounts was found to be more extreme than in the surrounding desert yet beneath the panels temperature is lower and relative humidity higher than outside the panel area. Arthropod species composition was altered in fixed-mount panel installations. In contrast, solar tracking technology showed less influence on microclimate and species composition between Sun and Shade in the power plant. Shady conditions provided a refuge for arthropod species in both installation types. For example, Dipterans were more abundant in the shade whereas Solifugaes were seldom present in the shade. The presented findings have relevance for the sustainable planning and construction of solar power plants.
Asunto(s)
Biota , Microclima , Centrales Eléctricas , Energía Solar , Animales , Artrópodos/fisiología , Biodiversidad , Chile , Conservación de los Recursos Energéticos , TemperaturaRESUMEN
Paul Cézanne is an acknowledged pioneer of modern painting. His work was poorly recognized during most of his solitary life. He progressively withdrew from people and society during his life, in part due to his introverted personality and a supreme effort to obtain a unique form of expression of his art, in which nature and its inner secrets played a pivotal role. In this review, we discuss aspects of his life and art, his pathological personal relationships and how they influenced his transcendental work.
Asunto(s)
Personajes , Neurociencias , Pinturas/historia , Francia , Historia del Siglo XIX , Historia del Siglo XX , Humanos , SoledadRESUMEN
BACKGROUND: Bladder perforation by ventriculoperitoneal shunt is a rare complication that has been describe in 19 cases in prior literature. CASE DESCRIPTION: This work describes the case of a 4-month-old baby who presented with extrusion of the distal catheter through the urethra. The patient underwent a laparotomy; the catheter was cut close to the bladder wall and repositioned into the peritoneal cavity. The bladder wall was sutured, and the remaining distal portion of the catheter was removed through the urethra. DISCUSSION AND CONCLUSION: Based on this single experience and a literature review, the authors classified the clinical signs and symptoms of bladder perforation by the ventriculoperitoneal shunt catheter. Finally, the authors propose a more conservative approach for this rare complication.
Asunto(s)
Vejiga Urinaria/lesiones , Derivación Ventriculoperitoneal/efectos adversos , Femenino , Humanos , LactanteRESUMEN
Time series of vegetation indices and remotely sensed phenological data offer insights about the patterns in vegetation dynamics. Both are useful sources of information for analyzing and monitoring ecosystem responses to environmental variations caused by natural and anthropogenic drivers. In the semi-arid region of Chile, climate variability and recent severe droughts in addition to land-use changes pose threats to the stability of local ecosystems. Normalized difference vegetation index time series (2000-2013) data from the moderate resolution imaging spectroradiometer (MODIS) was processed to monitor the trends and patterns of vegetation productivity and phenology observed over the last decade. An analysis of the relationship between (i) vegetation productivity and (ii) precipitation and temperature data for representative natural land-use cover classes was made. Using these data and ground measurements, productivity estimates were projected for two climate change scenarios (RCP2.6 and RCP8.5) at two altitudinal levels. Results showed negative trends of vegetation productivity below 2000 m a.s.l. and positive trends for higher elevations. Phenology analysis suggested that mountainous ecosystems were starting their growing period earlier in the season, coinciding with a decreased productivity peak during the growing season. The coastal shrubland/grassland land cover class had a significant positive relation with rainfall and a significant negative relation with temperature, suggesting that these ecosystems are vulnerable to climate change. Future productivity projections indicate that under an RCP8.5 climate change scenario, productivity could decline by 12% in the period of 2060-2100, leading to a severe vegetation degradation at lower altitudes and in drier areas.
Asunto(s)
Cambio Climático , Desarrollo de la Planta , Altitud , Chile , Clima , Sequías , Ecosistema , Monitoreo del Ambiente , Pradera , Ríos , Imágenes Satelitales , Estaciones del Año , TemperaturaRESUMEN
Frédéric Chopin - a great Polish composer and pianist-suffered from a chronic disease. Both during his life and after his death, physicians disagreed on Chopin's diagnosis. His contemporaries accepted the diagnosis of tuberculosis, a common disease in the 18th century. Description of new clinical entities provoked new dilemmas in the 21th century. Although other alternative diagnoses to tuberculosis have emerged, such as cystic fibrosis or alpha-1 antitrypsin deficiency, we still sustain that the first diagnosis is the most probable. In this paper we report F. Chopin's case history and discuss cons and pros for different diseases as the cause of F. Chopin's suffering and death.
Asunto(s)
Personajes , Música/historia , Fibrosis Quística/historia , Historia del Siglo XVIII , Historia del Siglo XIX , Tuberculosis Pulmonar/historia , Deficiencia de alfa 1-Antitripsina/historiaRESUMEN
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/κ-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC50) derived from dose-response artificial diet assays of 27, 20 and 52 µM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies.
Asunto(s)
Citrus , Hemípteros , Liberibacter , Animales , Hemípteros/fisiología , Neurotoxinas , Citrus/microbiología , Enfermedades de las Plantas/microbiologíaRESUMEN
The Asian Citrus Psyllid (ACP), Diaphorina citri, is a vector of the pathological bacterium Candidatus Liberibacter asiaticus (CLas), which causes the most devastating disease to the citrus industry worldwide, known as greening or huanglongbing (HLB). Earlier field tests with an acetic acid-based lure in greening-free, 'Valencia' citrus orange groves in California showed promising results. The same type of lures tested in São Paulo, Brazil, showed unsettling results. During the unsuccessful trials, we noticed a relatively large proportion of females in the field, ultimately leading us to test field-collected males and females for Wolbachia and CLas. The results showed high rates of Wolbachia and CLas infection in field populations. We then compared the olfactory responses of laboratory-raised, CLas-free, and CLas-infected males to acetic acid. As previously reported, CLas-uninfected males responded to acetic acid at 1 µg. Surprisingly, CLas-infected males required 50 × higher doses of the putative sex pheromone, thus explaining the failure to capture CLas-infected males in the field. CLas infection was also manifested in electrophysiological responses. Electroantennogram responses from CLas-infected ACP males were significantly higher than those obtained with uninfected males. To the best of our knowledge, this is the first report of a pathogen infection affecting a vector's response to a sex attractant.
Asunto(s)
Citrus sinensis , Citrus , Hemípteros , Rhizobiaceae , Atractivos Sexuales , Wolbachia , Femenino , Masculino , Animales , Hemípteros/fisiología , Atractivos Sexuales/farmacología , Brasil , Citrus/microbiología , Rhizobiaceae/fisiología , Acetatos , Enfermedades de las Plantas/microbiologíaRESUMEN
Full-thickness cutaneous trauma, due to the lack of dermis, leads to difficulty in epithelialization by keratinocytes, developing a fibrotic scar, with less elasticity than the original skin, which may have disorders in predisposed individuals, resulting in hypertrophic scar and keloids. Biomedical materials have excellent characteristics, such as good biocompatibility and low immunogenicity, which can temporarily replace traditional materials used as primary dressings. In this work, we developed two dermal matrices based on Nile tilapia collagen, with (M_GAG) and without (M) glycosaminoglycans, using a sugarcane polymer membrane as a matrix support. To assess the molecular mechanisms driving wound healing, we performed qualitative proteomic analysis on the wound bed in an in vivo study involving immunocompetent murine models at 14 and 21 days post-full-thickness skin injury. Gene Ontology and Pathway analysis revealed that both skins were markedly represented by modulation of the immune system, emphasizing controlling the acute inflammation response at 14 and 21 days post-injury. Furthermore, both groups showed significant enrichment of pathways related to RNA and protein metabolism, suggesting an increase in protein synthesis required for tissue repair and proper wound closure. Other pathways, such as keratinization and vitamin D3 metabolism, were also enriched in the groups treated with M matrix. Finally, both matrices improved wound healing in a full post-thick skin lesion. However, our preliminary molecular data reveals that the collagen-mediated healing matrix lacking glycosaminoglycan (M) exhibited a phenotype more favorable to tissue repair, making it more suitable for use before skin grafts.