RESUMO
Plant sterols are minor bioactive components of food lipids, which are often used for the formulation of functional foods due to their cholesterol-lowering properties. However, they have low solubility and tend to crystallize, which may affect their biological effects, the sensory profile of the sterol-enriched food, and its consumer acceptability. Moreover, due to the unsaturated structure of sterols, they are susceptible to oxidation, so different encapsulation systems have been developed to improve their dispersibility/solubility, stability, delivery, and bioaccessibility. This chapter provides an overview of the main encapsulation systems currently used for plant sterols and their application in model and food systems, with a particular focus on their efficiency and impact on sterol bioaccessibility.
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Fitosteróis , Colesterol , Alimentos Fortificados , Oxirredução , Fitosteróis/química , Fitosteróis/metabolismo , EsteróisRESUMO
Biofilms are ubiquitous bacterial communities that grow in various porous media including soils, trickling, and sand filters. In these environments, they play a central role in services ranging from degradation of pollutants to water purification. Biofilms dynamically change the pore structure of the medium through selective clogging of pores, a process known as bioclogging. This affects how solutes are transported and spread through the porous matrix, but the temporal changes to transport behavior during bioclogging are not well understood. To address this uncertainty, we experimentally study the hydrodynamic changes of a transparent 3-D porous medium as it experiences progressive bioclogging. Statistical analyses of the system's hydrodynamics at four time points of bioclogging (0, 24, 36, and 48 h in the exponential growth phase) reveal exponential increases in both average and variance of the flow velocity, as well as its correlation length. Measurements for spreading, as mean-squared displacements, are found to be non-Fickian and more intensely superdiffusive with progressive bioclogging, indicating the formation of preferential flow pathways and stagnation zones. A gamma distribution describes well the Lagrangian velocity distributions and provides parameters that quantify changes to the flow, which evolves from a parallel pore arrangement under unclogged conditions, toward a more serial arrangement with increasing clogging. Exponentially evolving hydrodynamic metrics agree with an exponential bacterial growth phase and are used to parameterize a correlated continuous time random walk model with a stochastic velocity relaxation. The model accurately reproduces transport observations and can be used to resolve transport behavior at intermediate time points within the exponential growth phase considered.
RESUMO
The capability of different bacterial populations to degrade abundant polymers, such as algal-derived polysaccharides, or to utilize preferentially polymers over monomers, remains largely unknown. In this study, microautoradiography was combined with fluorescence in situ hybridization (MAR-FISH) to evaluate the ability of Bacteroidetes, SAR11, Roseobacter spp., Gammaproteobacteria and SAR86 cells to use bicarbonate, leucine and starch under natural light conditions at two locations in shelf surface waters off NW Spain. The percentage of cells incorporating bicarbonate was relatively high (mean 32% ± 4%) and was positively correlated with the intensity of solar radiation. The proportion of cells using starch (mean 56% ± 4%) or leucine (mean 47% ± 4%) was significantly higher than that using bicarbonate. On average, SAR11, Roseobacter spp. and Gammaproteobacteria showed a similarly high percentage of cells using leucine (47%-65% of hybridized cells) than using starch (51%-64% of hybridized cells), while Bacteroidetes and SAR86 cells preferentially used starch (53% of hybridized cells) over leucine (34%-40% of hybridized cells). We suggest that the great percentage of bacteria using starch is related to a high ambient availability of polymers associated to algal cell lysis, which, in turn, weakens the short-term coupling between phytoplankton release and bacterial production.
Assuntos
Bacteroidetes/metabolismo , Bicarbonatos/metabolismo , Gammaproteobacteria/metabolismo , Leucina/metabolismo , Roseobacter/metabolismo , Amido/metabolismo , Autorradiografia , Bacteroidetes/genética , Gammaproteobacteria/genética , Hibridização in Situ Fluorescente , Fitoplâncton/metabolismo , Roseobacter/genética , Água do Mar/microbiologia , Espanha , Microbiologia da ÁguaRESUMO
INTRODUCTION: The Spanish Mohs Surgery Registry is used to collect data on the use and outcomes of Mohs micrographic surgery (MMS) in Spain. The aim of this study was to describe perioperative and intraoperative data recorded for MMS procedures performed between July 2013 (when the registry started) and January 2016. MATERIAL AND METHODS: Prospective cohort study of data from 18 hospitals. The data collected included type of anesthesia, surgical technique, hospital admission, number of Mohs stages, management of preoperative risk factors, additional treatments, previous treatments, type of tumor, operating time, and complications. RESULTS: Data were available for 1796 operations. The most common tumor treated by MMS was basal cell carcinoma (85.96%), followed by squamous cell carcinoma (6.18%), lentigo maligna (2.81%), and dermatofibrosarcoma protuberans (1.97%). Primary tumors accounted for 66.9% of all tumors operated on; 19.2% of tumors were recurrent and 13.9% were persistent. The most common previous treatment was surgical. MMS was mostly performed under local anesthesia (86.7% of cases) and as an outpatient procedure (71.8%). The frozen section technique was used in 89.5% of cases. One stage was needed to achieve tumor-free margins in 56.45% of patients; 2 stages were required in 32.1% of patients, 3 in 7.1%%, 4 in 2.7%, and 5 or more in 1.8%. The defect was reconstructed by the dermatologist in 98% of patients and the most common technique was flap closure (47.2%). Intraoperative complications were recorded for just 1.62% of patients and the median (interquartile range) duration of surgery was 75 (60-100) minutes. CONCLUSION: The characteristics of the patients and tumors treated by MMS are similar to those reported for similar studies in other geographic areas. Lentigo maligna and dermatofibrosarcoma protuberans accounted for a higher proportion of cases in our series, and repair of the surgical defect by a dermatologist was also more common. Operating times in MMS are not much longer than those reported for other procedures and the rate of intraoperative complications is very low.
Assuntos
Cirurgia de Mohs/estatística & dados numéricos , Neoplasias Cutâneas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Anestesia/métodos , Anestesia/estatística & dados numéricos , Terapia Combinada , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Cirurgia de Mohs/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Sistema de Registros , Gestão de Riscos , Neoplasias Cutâneas/terapia , Espanha , Retalhos CirúrgicosRESUMO
BACKGROUND: Alterations in the host cellular immune response allow persistent infections with High-Risk Human Papillomavirus (HR-HPV) and development of premalignant cervical lesions and cervical cancer (CC). Variations of immunosuppressive cytokine levels in cervix are associated with the natural history of CC. To assess the potential role of genetic host immunity and cytokines serum levels in the risk of developing CC, we conducted a case-control study paired by age. METHODS: Peripheral blood samples from patients with CC (n = 200) and hospital controls (n = 200), were used to evaluate nine biallelic SNPs of six cytokine genes of the adaptive immune system by allelic discrimination and cytokines serum levels by ELISA. RESULTS: After analyzing the SNP association by multivariate logistic regression adjusted by age, CC history and smoking history, three Th2 cytokines (IL-4, IL-6 and IL-10) and one Th3 (TGFB1) cytokine were significantly associated with CC. Individuals with at least one copy of the following risk alleles: T of SNP (-590C > T IL-4), C of SNP (-573G > C IL-6), A of SNP (-592C > A IL-10), T of SNP (-819C > T IL-10) and T of SNP (-509C > T TGFB1), had an adjusted odds ratio (OR) of 2.08 (95 % CI 1.475-2.934, p = 0.0001), an OR of 1.70 (95 % CI 1.208-2.404, p = 0.002), an OR of 1.87 (95 % CI 1.332-2.630, p = 0.0001), an OR of 1.67 (95 % CI 1.192-2.353, p = 0.003) and an OR of 1.91 (95 % CI 1.354-2.701, p = 0.0001), respectively, for CC. The burden of carrying two or more of these risk alleles was found to have an additive effect on the risk of CC (p trend = 0.0001). Finally, the serum levels of Th2 and Th3 cytokines were higher in CC cases than the controls; whereas IFNG levels, a Th1 cytokine, were higher in controls than CC cases. CONCLUSION: The significant associations of five SNPs with CC indicate that these polymorphisms are potential candidates for predicting the risk of development of CC, representing a risk allelic load for CC and can be used as a biomarker of susceptibility to this disease.
Assuntos
Carcinoma de Células Escamosas/genética , Citocinas/genética , Infecções por Papillomavirus/genética , Polimorfismo de Nucleotídeo Único/genética , Células Th1/metabolismo , Células Th2/metabolismo , Neoplasias do Colo do Útero/genética , Adulto , Alelos , Biomarcadores , Biomarcadores Tumorais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Papillomavirus Humano 16/fisiologia , Humanos , Estadiamento de Neoplasias , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Prognóstico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologiaRESUMO
Pediatric intensive care is a relatively new medical specialty, which has experienced significant technological advances in recent years. These developments have led to a prolongation of the dying process, with additional suffering for patients and their families, creating complex situations, and often causing a painful life extension. The term, limitation of the therapeutic effort refers to the adequacy and/or proportionality of the treatment, trying to avoid obstinacy and futility. The English literature does not talk about limitation of treatments, but instead the terms, withholding or withdrawal of life-sustaining treatment, are used. The removal or the non-installation of certain life support measures and the absence of CPR are the types of limitation most used. Also, there is evidence of insufficient medical training in bioethics, which is essential, as most doctors in the PICU discuss and make decisions regarding the end of life without the opinion of bioethicists. This article attempts to review the current status of knowledge concerning the limitation of therapeutic efforts to support pediatric clinical work.
Assuntos
Unidades de Terapia Intensiva Pediátrica/organização & administração , Assistência Terminal/organização & administração , Suspensão de Tratamento , Temas Bioéticos , Criança , Humanos , Unidades de Terapia Intensiva Pediátrica/ética , Futilidade Médica , Estresse Psicológico/psicologia , Assistência Terminal/ética , Suspensão de Tratamento/éticaRESUMO
OBJECTIVE: This study aimed to characterize the prevalence as well as clinical and epidemiological features of persistent symptoms after acute COVID-19, focusing on gender-specific differences in a primary care setting. METHODS: A total of 1542 individuals with confirmed SARS-CoV-2 infection were enrolled. The study population comprised 55.77% females (mean age: 45.04 years). Risk factors for persistent COVID-19 were analyzed, revealing disparities between men and women. Symptom clusters and their prevalence were assessed over time, along with functional status using the post-COVID-19 functional status scale. RESULTS: The prevalence of persistent COVID-19 was 12.38%, with females exhibiting a 1.5 times higher risk. Females displayed a higher number of visits and persistent symptoms at 90 days, decreasing after one year. Symptom clusters varied between genders, with females experiencing more dermatological issues. Functional status analysis revealed that females had a better pre-infection status, similar status to males at 90 days, and improved status at 180-, 270-, and 365-days post-infection. Logistic regression analysis showed significant associations between persistence, gender, hospitalization, radiological abnormalities, age, and immunosuppression. CONCLUSION: This study provides insights into the prevalence and clinical characteristics of persistent COVID-19 in a primary care population. Females exhibited a higher risk of persistent symptoms and displayed distinct patterns in symptom clusters and functional status compared to males. These findings contribute to a better understanding of the long-term effects of COVID-19 and highlight the importance of gender-specific considerations in post-acute care.
Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , Atenção Primária à Saúde , Humanos , Feminino , Masculino , COVID-19/epidemiologia , COVID-19/complicações , Pessoa de Meia-Idade , Fatores Sexuais , Fatores de Risco , Adulto , Prevalência , Atenção Primária à Saúde/estatística & dados numéricos , Idoso , Hospitalização/estatística & dados numéricos , Fatores de Tempo , Adulto JovemRESUMO
The first step in the catabolism of cholesterol, i.e. the transformation of cholesterol into cholestenone, has been investigated in Mycobacterium smegmatis. In silico analysis identified the MSMEG_1604 gene encoding a putative protein similar to the ChoD cholesterol oxidase of M. tuberculosis H37Rv (Rv3409c) and the MSMEG_5228 gene coding for a protein similar to the NAD(P)-dependent cholesterol dehydrogenase/isomerase of Nocardia sp. The expression of the MSMEG_5228 gene was inducible by cholesterol whereas the expression of MSMEG_1604 gene was constitutive. When both genes were expressed in Escherichia coli only the MSMEG_5228 protein was active on cholesterol. The function of ChoD-like MSMEG_1604 protein remains to be elucidated, but it does not appear to play a critical role in the mineralization of cholesterol as a MSMEG_1604(-) mutant was not affected in the production of cholestenone. However, a MSMEG_5228(-) mutant showed a drastic reduction in the synthesis of cholestenone. The finding that this mutant was still able to grow in cholesterol, allowed us to demonstrate that the cholesterol-inducible MSMEG_5233 gene encodes an additional cholesterol dehydrogenase/isomerase similar to the AcmA dehydrogenase of Sterolibacterium denitrificans. The observation that the double MSMEG_5228-5233(-) mutant was able to grow in cholesterol suggests that in addition to these enzymes other dehydrogenase/isomerases can also catalyse the first reaction of the cholesterol degradation pathway in M. smegmatis, which is not the limiting step of the process.
Assuntos
Colesterol/metabolismo , Isomerases/metabolismo , Mycobacterium smegmatis/enzimologia , Oxirredutases/metabolismo , Sequência de Aminoácidos , Colestenonas/metabolismo , Análise Mutacional de DNA , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Isomerases/genética , Dados de Sequência Molecular , Mutação , Mycobacterium smegmatis/genética , Oxirredutases/genética , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
This paper reports physiological and genetic data about the type strain Gordonia cholesterolivorans, a strain that is able to degrade steroid compounds containing a long carbon side chain such as cholesterol (C(27)), cholestenone (C(27)), ergosterol (C(28)), and stigmasterol (C(29)). The length of the carbon side chain appears to be of great importance for this bacterium, as the strain is unable to grow using steroids with a shorter or nonaliphatic carbon side chain such as cholic acid (C(24)), progesterone (C(21)), testosterone, androsterone, 4-androstene-3,17-dione (all C(19)), and further steroids. This study also demonstrates that the degradation of cholesterol is a quite common feature of the genus Gordonia by comparing Gordonia cholesterolivorans with some other species of this genus (e.g., G. sihwensis, G. hydrophobica, G. australis, and G. neofelifaecis). Pyrosequencing of the genome of G. cholesterolivorans led to the identification of two conventional cholesterol oxidase genes on an 8-kb and a 12.8-kb genomic fragment with genetic organizations that are quite unique as compared to the genomes of other cholesterol-degrading bacteria sequenced so far. The identified two putative cholesterol oxidases of G. cholesterolivorans are both intracellularly acting enzymes of the class I type. Whereas one of these two cholesterol oxidases (ChoOx-1) shows high identity with an oxidoreductase of the opportunistic pathogen G. bronchialis and is not transcribed during growth with cholesterol, the other one (ChoOx-2) appears phylogenetically closer to cholesterol oxidases from members of the genus Rhodococcus and is transcribed constitutively. By using targeted gene disruption, a G. cholesterolivorans ChoOx-2 gene mutant strain that was unable to grow with steroids was obtained.
Assuntos
Colesterol Oxidase/genética , Colesterol/metabolismo , Bactéria Gordonia/metabolismo , Sequência de Bases , Carbono/metabolismo , Colestenonas/metabolismo , Colesterol Oxidase/química , Colesterol Oxidase/isolamento & purificação , Cromatografia Líquida , DNA Bacteriano/genética , Ergosterol/metabolismo , Bactéria Gordonia/genética , Bactéria Gordonia/crescimento & desenvolvimento , Espectrometria de Massas , Dados de Sequência Molecular , Mutação , Filogenia , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Estigmasterol/metabolismoRESUMO
Parkinson's disease (PD) is a progressive neurodegenerative disease, the 2nd most common after Alzheimer's disease, the main effect of which is the loss of dopaminergic neurons. Levodopa or l-Dopa is an amino acid used in the treatment of PD that acts as the immediate precursor to dopamine. However, over time the efficacy of the medication gradually decreases requiring modified delivery methods. One of the major challenges for the medication to work is to achieve a gradual continuous supply of l-Dopa to the brain to minimise symptoms. Herein, mesoporous silica nanoparticles (MSNs) were engineered through the concept of drug-structure-directing agents (DSDAs) with inherent therapeutic activity. The DSDA used was l-Dopa drug modified by amidation with fatty acids to build anionic surfactants that were able to form micelles as templates for the assembly of inorganic precursors to form the silica framework. This templating route produced MSNs with tunable sizes ranging from 100 nm to 1 µm and with different shapes: spherical, with either solid structures with radial mesopores and porous shells, or hollow-shells with inside large void cavities; and elongated, characterized by long hollows covered by mesoporous shells. The concept of using DSDAs to synthesize drug nanocarriers can be used to avoid the surfactant removal and subsequent drug loading steps involved in the synthesis of conventional MSNs. We hypothesized that the l-Dopa released from MSN materials is mediated by the size and solubility of the DSDAs, and the surface chemical interactions between the DSDAs and MSN hosts. Different pHs (acidic and neutral) simulating gastrointestinal tract conditions were tested, and the results showed hardly any release for gastric conditions at pH 1.2, avoiding the premature release in the stomach typical of conventional MSNs, while for intestinal conditions of pH 7.4, the release of l-Dopa occurred in a continuous and sustained manner, which is well suited to the drug's application and delivery route, and matches well with achieving a sustained l-Dopa delivery to relief symptoms. This could open up new uses for MSNs synthesized by this approach to treat PD.
Assuntos
Antiparkinsonianos/uso terapêutico , Levodopa/uso terapêutico , Nanopartículas/química , Doença de Parkinson/tratamento farmacológico , Dióxido de Silício/química , Antiparkinsonianos/síntese química , Antiparkinsonianos/química , Liberação Controlada de Fármacos , Humanos , Levodopa/síntese química , Levodopa/química , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
INTRODUCTION: The treatment of acute lymphoblastic leukemia (ALL) includes the use of asparaginase (ASP), a drug associated with hypersensitivity reactions (HSR) that requires discontinuing its use. OBJECTIVE: To determine the incidence of HSR associated with ASP that require discontinuation of its use and des cribe them, and to verify if there is a relationship between HSR incidence and protocols or survival. PATIENTS AND METHOD: Retrospective study. Clinical records of all patients (1-15 years) diagnosed with ALL between January 2010 and December 2015 at the Hospital Luis Calvo Mackenna were reviewed. The incidence of HSR to ASP was determined and classified according to the CTCAE v5.0 severity score. We analyzed the relative risk of HSR using Fisher's test and the survival with the Kaplan-Meier estimator. RESULTS: 110 patients were collected. During the first treatment (ALL-IC- BFM), the incidence of HSR to L-ASP was 55%, therefore it was changed to PEG-ASP as second-line treatment, and 44% of them had HSR, and ASP should discontinued in 25% of patients. Of all the HSR to ASP, 77% were anaphylactic (CTCAE 3-5). Patients treated with augmented IB protocol were at higher risk of not completing ASP treatment due to HSR, RR 3.81 (95% CI, 1.98-7.31, p = 0.0001). Patients without HSR in ALL-IC-BFM were at lower risk of relapse, HR 0.29 (95% CI, 0.14-0.62, p = 0.0013). Considering all treatments (ALL-IC-BFM and relapse), patients who completed the ASP treatment had higher overall survival, HR 0.20 (95% CI, 0.07-0.57, p = 0.0026). CONCLUSIONS: HSR to ASP that require discontinuation of treatment are frequent in children with ALL, most of them were severe anaphylactic reactions. This study suggests a better prognosis in patients without HSR to ASP.
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Antineoplásicos/efeitos adversos , Asparaginase/efeitos adversos , Hipersensibilidade a Drogas/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Anafilaxia/induzido quimicamente , Antineoplásicos/uso terapêutico , Asparaginase/uso terapêutico , Criança , Pré-Escolar , Substituição de Medicamentos , Feminino , Humanos , Incidência , Lactente , Estimativa de Kaplan-Meier , Masculino , Polietilenoglicóis/uso terapêutico , Prognóstico , Estudos RetrospectivosRESUMO
Leishmaniasis affects mainly rural areas and the poorest people in the world. A computational study of the antileishmanial activity of organic selenium and tellurium compounds was performed. The 3D structures of the compounds were optimized at the wb97xd/lanl2dz level and used in the quantitative structure-activity relationship (QSAR) analysis. The antileishmanial activity was measured by L. donovani ß carbonic anhydrase inhibition (Ki) and the half-maximal inhibitory concentration (IC50) against L. infantum amastigotes. The dataset was divided into training (75%) and test sets (25%) by using a k-means clustering algorithm. For pKi prediction, model M3 with seven 3D topographic descriptors was characterized by the following statistical parameters: r 2 = 0.879, Q 2 LOO = 0.822, and Q 2 ext = 0.840. For pIC50 prediction, model M12 with six attributes was characterized by the following statistical parameters: r 2 = 0.907, Q 2 LOO = 0.824, and Q 2 ext = 0.795. Both models met all the requirements of Tropsha´s test, which implies predictions of pIC50 and pKi activities with high accuracy. Concomitantly, favourable interactions of the sulphonamide group with the Zn atom in the protein were revealed by the docking analysis.
Assuntos
Antiprotozoários/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Compostos de Selênio/farmacologia , Telúrio/farmacologiaRESUMO
CLINICAL CASE: A 46-year-old caucasian male with a history of chronic conjunctival hyperemia, presented at our clinic 5 years after he underwent the surgical procedure of cosmetic eye whitening. On examination we observed pyogenic granuloma in the right eye; besides acute nongranulomatous anterior uveitis and necrotizing scleritis in both eyes. RESULT: Complete clinical evaluation and full work-up exclusion of systemic diseases was done. The pyogenic granuloma was treated with surgical resection, as well as anterior uveitis and necrotizing scleritis were successfully treated with systemic corticoesteroids and methotrexate. CONCLUSION: The surgical cosmetic eye whitening could have as complication the pyogenic granuloma in addition to necrotizing scleritis and nongranulomatous anterior uveitis; and be present 5 years after the procedure. The surgical resection is a successful treatment for this presentation of pyogenic granuloma.
RESUMO
Feather mites are the most numerous group of symbionts permanently associated to birds. They are highly specialized to particular microhabitats on their hosts and most of them may be considered as commensals, but several species are parasites. This manuscript documents for the first time a combined infestation by quill mites Dermoglyphus passerinusGaud, 1974 (Analgoidea: Dermoglyphidae) and feather mites Strelkoviacarus sp.(Analgidae: Anomalginae), in domestic canaries (Serinus canaria domestica) (Linnaeus, 1758) (Passeriformes: Fringillidae) in Mexico City, Mexico. Description of the case, the feather and skin lesions, and findings associated with the infection are presented. This manuscript aims to contribute to the knowledge of mite species that can affect the plumage of Serinus canaria domestica; as well as to the diagnosis and control of these infestations.
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Doenças das Aves/parasitologia , Canários , Infestações por Ácaros/veterinária , Animais , Feminino , Masculino , México , Infestações por Ácaros/parasitologia , ÁcarosRESUMO
A project of the 15th International Histocompatibility Workshop examined the rarity of human leukocyte antigen (HLA) alleles. A section was constructed in the website, www.allelefrequencies.net to contain this data from different sources. A mechanism to search the data was implemented for use by any individual.
Assuntos
Alelos , Biologia Computacional , Antígenos HLA/genética , Bases de Dados Factuais , HumanosRESUMO
OBJECTIVE: Our aims were to examine the ability of the human papillomaviruse (HPV) 16 E2 protein to induce apoptosis in a murine HPV-transformed cell line, and to evaluate its antitumor properties on HPV-associated tumors in vivo in immunocompetent mice. METHODS: HPV-transformed murine BMK-16/myc cells and human SiHa cells were transfected with the HPV 16 E2 gene to examine the effects of the E2 protein on cell growth and on the E6 and E7 oncogenes as well as DNA fragmentation and activation of the extrinsic pathway of apoptosis. Finally, to test the antitumor effect of the E2 protein on an experimental mouse tumor model, we generated a recombinant adenovirus expressing the E2 protein. RESULTS: The E2 protein inhibited the growth of SiHa and BMK-16/myc cell lines, and repressed the E6 and E7 oncogenes. Moreover, the E2 protein induced DNA fragmentation and apoptosis through activation of caspases 8 and 3 in BMK-16/myc cells. On the other hand, E2 also showed antitumor effects in vivo. CONCLUSIONS: Our findings indicate that E2 exerts pro-apoptotic activity in a murine HPV-transformed cell line as well as an antitumor effect in vivo.
Assuntos
Apoptose , Transformação Celular Viral , Proteínas de Ligação a DNA/metabolismo , Terapia Genética , Papillomavirus Humano 16/fisiologia , Neoplasias/terapia , Proteínas Oncogênicas Virais/metabolismo , Adenoviridae/genética , Adenoviridae/metabolismo , Animais , Linhagem Celular Transformada , Linhagem Celular Tumoral , Fragmentação do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/uso terapêutico , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Papillomavirus Humano 16/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/virologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/uso terapêuticoRESUMO
In the present study, the hemagglutinating activity of seven reference strains, and nine Mexican and three Danish field isolates, of Gallibacterium was investigated by using fresh erythrocytes of 19 different types including chicken (broiler, rooster, layer hen), turkey, pigeon, quail, duck, Harris's hawk (Parabuteo unicinctus), house finch (Carpodacus mexicanus), cow, sheep, horse, dog, rabbit, pig, and human (groups A, B, AB, and O; Rh+). Agglutination was observed for broiler chicken, layer hen, quail, rabbit, and pig erythrocytes with a subset of Gallibacterium strains, whereas most tested strains agglutinated rabbit erythrocytes. Transmission electron microscopic examination of a hemagglutinating strain demonstrated a close interaction between the bacterial and erythrocyte surfaces. The results indicate that some Gallibacterium strains are able to agglutinate avian or mammalian erythrocytes, or both. However, the mechanisms enabling hemagglutination are not known and will be addressed in future studies.
Assuntos
Hemaglutinação/fisiologia , Pasteurellaceae/classificação , Pasteurellaceae/fisiologia , Animais , Eritrócitos/fisiologia , HumanosRESUMO
Although strigolactones play a critical role as rhizospheric signaling molecules for the establishment of arbuscular mycorrhizal (AM) symbiosis and for seed germination of parasitic weeds, scarce data are available about interactions between AM fungi and strigolactones. In the present work, we present background data on strigolactones from studies on their seed germination activity on the parasitic weeds Orobanche and Striga, the importance of nitrogen and phosphorus for this seed germination activity, and what this could mean for AM fungi. We also present results on the susceptibility of plants to AM fungi and the possible involvement of strigolactones in this AM susceptibility and discuss the role of strigolactones for the formation and the regulation of the AM symbiosis as well as the possible implication of these compounds as plant signals in other soil-borne plant-microbe interactions.
Assuntos
Fungos/fisiologia , Lactonas/metabolismo , Magnoliopsida/fisiologia , Micorrizas/fisiologia , Plantas/metabolismo , Ecossistema , Germinação , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plantas/microbiologia , SimbioseRESUMO
This study reports an outbreak of avian pox in a quarantine of canaries imported from Europe, with a mortality of 30% and clinical signs of dyspnea and blepharoconjunctivitis. During necropsy, beak cyanosis, serous blepharitis, caseous sinusitis, oropharyngitis, tracheitis, pulmonary edema, pneumonia, fibrinous airsacculitis, and splenomegaly were observed. Microscopically, edema, epithelial hyperplasia, hydropic degeneration, and vacuolated eosinophilic intracytoplasmic inclusion bodies were found; similar lesions were observed in the thymus, spleen, and other organs. The virus was isolated in chicken embryos, and it was identified and characterized using a sequence of 913 nucleotides of the DNA polymerase gene. Pathologic characteristics and molecular biology indicate the systemic presence of avian pox associated with an avipoxvirus of the B1 subgroup. Additionally, other lesions associated with Aspergillus sp., Macrorhabdus ornithogaster, and Isospora sp. were found, which could contribute to the high mortality. Canarypox virus should be considered a differential diagnosis in cases of dyspnea and high mortality in canary flocks.
Reporte de caso- Brote de viruela aviar sistémica en canarios (Serinus canaria domestica) asociado con el virus de la viruela aviar subgrupo B1. En este estudio se reporta un brote de viruela aviar en unos canarios importados de Europa que estaban bajo cuarentena, con una mortalidad del 30% y signos clínicos de disnea y blefaroconjuntivitis. Durante la necropsia, se observó cianosis de pico, blefaritis serosa, sinusitis caseosa, orofaringitis, traqueítis, edema pulmonar, neumonía, fibrinosa respiratoria y esplenomegalia. Microscópicamente, se encontró edema, hiperplasia epitelial, degeneración hidrópica y cuerpos de inclusión intracitoplásmicos eosinófilos vacuolados; Se observaron lesiones similares en el timo, el bazo y otros órganos. El virus se aisló en embriones de pollo, se identificó y caracterizó analizando una secuencia de 913 nucleótidos del gene de la polimerasa de ADN. Las características patológicas y la biología molecular indican la presentación sistémica de la viruela aviar asociada a un avipoxvirus del subgrupo B1. Además, se encontraron otras lesiones asociadas con Aspergillus sp., Macrorhabdus ornithogaster y Isopora sp., lo que pudo contribuir a la alta mortalidad. El virus de la viruela del canario debe considerarse un diagnóstico diferencial en casos de disnea y alta mortalidad en parvadas de canarios.
Assuntos
Avipoxvirus/fisiologia , Doenças das Aves/epidemiologia , Canários , Surtos de Doenças/veterinária , Infecções por Poxviridae/veterinária , Animais , Avipoxvirus/classificação , Doenças das Aves/patologia , Doenças das Aves/virologia , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/patologia , Infecções por Poxviridae/virologiaRESUMO
Changes in the nature of the ecological resources exploited by a species can lead to the evolution of novel suites of behaviours. We identified a case in which the transition from large pool use to the use of very small breeding pools in neotropical poison frogs (family Dendrobatidae) is associated with the evolution of a suite of behaviours, including biparental care (from uniparental care) and social monogamy (from promiscuity). We manipulated breeding pool size in order to demonstrate experimentally that breeding habitat selection strategy has evolved in concert with changes in parental care and mating system. We also manipulated intra- and interspecific larval interactions to demonstrate that larval adaptation to the use of very small pools for breeding affected the evolution of larval competition and cannibalism. Our results illustrate the intimate connection between breeding pool ecology, parental care and mating strategies in Peruvian poison frogs.