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1.
Artigo em Inglês | MEDLINE | ID: mdl-38630118

RESUMO

The taxonomic position of three actinobacterial strains, BCCO 10_0061T, BCCO 10_0798T, and BCCO 10_0856T, recovered from bare soil in the Sokolov Coal Basin, Czech Republic, was established using a polyphasic approach. The multilocus sequence analysis based on 100 single-copy genes positioned BCCO 10_0061T in the same cluster as Lentzea waywayandensis, strain BCCO 10_0798T in the same cluster as Lentzea flaviverrucosa, Lentzea californiensis, Lentzea violacea, and Lentzea albidocapillata, and strain BCCO 10_0856T clustered together with Lentzea kentuckyensis and Lentzea alba. Morphological and chemotaxonomic characteristics of these strains support their assignment to the genus Lentzea. In all three strains, MK-9(H4) accounted for more than 80 % of the isoprenoid quinone. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The whole-cell sugars were rhamnose, ribose, mannose, glucose, and galactose. The major fatty acids (>10 %) were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, and C16 : 0. The polar lipids were diphosphatidylglycerol, methyl-phosphatidylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, and phosphatidylinositol. The genomic DNA G+C content of strains (mol%) was 68.8 for BCCO 10_0061T, 69.2 for BCCO 10_0798T, and 68.5 for BCCO 10_0856T. The combination of digital DNA-DNA hybridization results, average nucleotide identity values and phenotypic characteristics of BCCO 10_0061T, BCCO 10_0798T, and BCCO 10_0856T distinguishes them from their closely related strains. Bioinformatic analysis of the genome sequences of the strains revealed several biosynthetic gene clusters (BGCs) with identities >50 % to already known clusters, including BGCs for geosmin, coelichelin, ε-poly-l-lysine, and erythromycin-like BGCs. Most of the identified BGCs showed low similarity to known BGCs (<50 %) suggesting their genetic potential for the biosynthesis of novel secondary metabolites. Based on the above results, each strain represents a novel species of the genus Lentzea, for which we propose the name Lentzea sokolovensis sp. nov. for BCCO 10_0061T (=DSM 116175T), Lentzea kristufekii sp. nov. for BCCO 10_0798T (=DSM 116176T), and Lentzea miocenica sp. nov. for BCCO 10_0856T (=DSM 116177T).


Assuntos
Actinobacteria , Actinomycetales , Fosfatidiletanolaminas , República Tcheca , Composição de Bases , Ácidos Graxos/química , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias , Carvão Mineral
2.
Proc Natl Acad Sci U S A ; 117(36): 22281-22292, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32843340

RESUMO

Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth-ocean-atmosphere dynamic exchange of elements. The ratios' dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios' variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect.

3.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37958529

RESUMO

Umbilical cord blood (UCB) serves as a source of hematopoietic stem and progenitor cells (HSPCs) utilized in the regeneration of hematopoietic and immune systems, forming a crucial part of the treatment for various benign and malignant hematological diseases. UCB has been utilized as an alternative HSPC source to bone marrow (BM). Although the use of UCB has extended transplantation access to many individuals, it still encounters significant challenges in selecting a histocompatible UCB unit with an adequate cell dose for a substantial proportion of adults with malignant hematological diseases. Consequently, recent research has focused on developing ex vivo expansion strategies for UCB HSPCs. Our results demonstrate that co-cultures with the investigated mesenchymal stromal cells (MSCs) enable a 10- to 15-fold increase in the cellular dose of UCB HSPCs while partially regulating the proliferation capacity when compared to HSPCs expanded with early acting cytokines. Furthermore, the secretory profile of UCB-derived MSCs closely resembles that of BM-derived MSCs. Moreover, both co-cultures exhibit alterations in cytokine secretion, which could potentially impact HSPC proliferation during the expansion process. This study underscores the fact that UCB-derived MSCs possess a remarkably similar supportive capacity to BM-derived MSCs, implying their potential use as feeder layers in the ex vivo expansion process of HSPCs.


Assuntos
Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Gravidez , Feminino , Adulto , Humanos , Antígenos CD34 , Sangue Fetal , Células-Tronco Hematopoéticas , Técnicas de Cocultura , Transplante de Células-Tronco Hematopoéticas/métodos , Proliferação de Células
4.
Environ Dev Sustain ; : 1-47, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37362985

RESUMO

This study analyses how startups implement circular business models supported by innovation and Industry 4.0, in which strategic stakeholders for value creation are to be found in this specific business ecosystem. The theoretical framework of circular business models supported by innovation was used for analysing the startups based on some assumptions of stakeholder theory. Fifty-one startups were selected, which correspond to the unit of analysis for this study on the improvement of supply chains through circular business models supported by innovation aimed at sustainability in organizations. We conducted a multiple case study whose results suggest that: (i) circularity is strategic for the business to assume its commitment to a sustainable development agenda, especially regarding pollution prevention and proactive action; (ii) visionary entrepreneurs are actively engaged with circular economy practices and technological innovation to promote a circular flow for their business ecosystem; (iii) Industry 4.0 is still incipient, but it is synergistic and beneficial for a successful circular economy in startups; and (iv) primary stakeholders are the activators of circular cycles in the startups surveyed. The present study contributes to the literature in four ways by: (i) presenting a framework which brings together exploratory theoretical propositions on strategic stakeholders for startups, innovative capabilities and assumptions of circular business models; (ii) validating exploratory theoretical propositions with 51 startups; (iii) providing lessons learned so far by the startups which are in line with the assumptions of circular business models for triggering their innovation capabilities and promoting Industry 4.0; (iv) providing an original typology of circular economy assumptions and technological innovations adopted by startups. The originality of this study lies in presenting useful insights for motivating managers to: (i) invest in circular business to become one of the first entrants and earn extra profits; (ii) make investments in circular business and technological innovations to obtain efficiency, practicality and process optimization; (iii) internalize Industry 4.0 technologies concomitantly with technological innovations and circular economy to generate systemic effects; (iv) integrate relevant stakeholders of the business ecosystem to generate a synergistic and effective effect for sustainable development.

5.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499372

RESUMO

Streptomyces are of great interest in the pharmaceutical industry as they produce a plethora of secondary metabolites that act as antibacterial and antifungal agents. They may thrive on their own in the soil, or associate with other organisms, such as plants or invertebrates. Some soil-derived strains exhibit hemolytic properties when cultivated on blood agar, raising the question of whether hemolysis could be a virulence factor of the bacteria. In this work we examined hemolytic compound production in 23 ß-hemolytic Streptomyces isolates; of these 12 were soil-derived, 10 were arthropod-associated, and 1 was plant-associated. An additional human-associated S. sp. TR1341 served as a control. Mass spectrometry analysis suggested synthesis of polyene molecules responsible for the hemolysis: candicidins, filipins, strevertene A, tetrafungin, and tetrin A, as well as four novel polyene compounds (denoted here as polyene A, B, C, and D) in individual liquid cultures or paired co-cultures. The non-polyene antifungal compounds actiphenol and surugamide A were also identified. The findings indicate that the ability of Streptomyces to produce cytolytic compounds (here manifested by hemolysis on blood agar) is an intrinsic feature of the bacteria in the soil environment and could even serve as a virulence factor when colonizing available host organisms. Additionally, a literature review of polyenes and non-polyene hemolytic metabolites produced by Streptomyces is presented.


Assuntos
Streptomyces , Humanos , Streptomyces/química , Antifúngicos/farmacologia , Antifúngicos/química , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Polienos/farmacologia , Polienos/química , Hemólise , Fatores de Virulência/metabolismo
6.
Appl Environ Microbiol ; 87(15): e0061421, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34020937

RESUMO

Methanogens represent the final decomposition step in anaerobic degradation of organic matter, occurring in the digestive tracts of various invertebrates. However, factors determining their community structure and activity in distinct gut sections are still debated. In this study, we focused on the tropical millipede species Archispirostreptus gigas (Diplopoda, Spirostreptidae) and Epibolus pulchripes (Diplopoda, Pachybolidae), which release considerable amounts of methane. We aimed to characterize relationships between physicochemical parameters, methane production rates, and methanogen community structure in the two major gut sections, midgut and hindgut. Microsensor measurements revealed that both sections were strictly anoxic, with reducing conditions prevailing in both millipedes. Hydrogen concentration peaked in the anterior hindgut of E. pulchripes. In both species, the intestinal pH was significantly higher in the hindgut than in the midgut. An accumulation of acetate and formate in the gut indicated bacterial fermentation activities in the digestive tracts of both species. Phylogenetic analysis of 16S rRNA genes showed a prevalence of Methanobrevibacter spp. (Methanobacteriales), accompanied by a small fraction of so-far-unclassified "Methanomethylophilaceae" (Methanomassiliicoccales), in both species, which suggests that methanogenesis is mostly hydrogenotrophic. We conclude that anoxic conditions, negative redox potential, and bacterial production of hydrogen and formate promote gut colonization by methanogens. The higher activities of methanogens in the hindgut are explained by the higher pH of this compartment and their association with ciliates, which are restricted to this compartment and present an additional source of methanogenic substrates. IMPORTANCE Methane (CH4) is the second most important atmospheric greenhouse gas after CO2 and is believed to account for 17% of global warming. Methanogens are a diverse group of archaea and can be found in various anoxic habitats, including digestive tracts of plant-feeding animals. Termites, cockroaches, the larvae of scarab beetles, and millipedes are the only arthropods known to host methanogens and emit large amounts of methane. Millipedes are ranked as the third most important detritivores after termites and earthworms, and they are considered keystone species in many terrestrial ecosystems. Both methane-producing and non-methane-emitting species of millipedes have been observed, but what limits their methanogenic potential is not known. In the present study, we show that physicochemical gut conditions and the distribution of symbiotic ciliates are important factors determining CH4 emission in millipedes. We also found close similarities to other methane-emitting arthropods, which might be associated with their similar plant-feeding habits.


Assuntos
Artrópodes/microbiologia , Microbioma Gastrointestinal , Trato Gastrointestinal/metabolismo , Metano/metabolismo , Animais , Bactérias/genética , Bactérias/metabolismo , Formiatos/metabolismo , Microbioma Gastrointestinal/genética , Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Oxirredução , Oxigênio/análise , Filogenia , RNA Ribossômico 16S/genética
7.
Mol Ecol ; 30(2): 406-423, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33179370

RESUMO

Understanding how the environment shapes genetic variation provides critical insight about the evolution of local adaptation in natural populations. At multiple spatial scales and multiple geographic contexts within a single species, such information could address a number of fundamental questions about the scale of local adaptation and whether or not the same loci are involved at different spatial scales or geographic contexts. We used landscape genomic approaches from three local elevational transects and rangewide sampling to (a) identify genetic variation underlying local adaptation to environmental gradients in the California endemic oak, Quercus lobata; (b) examine whether putatively adaptive SNPs show signatures of selection at multiple spatial scales; and (c) map putatively adaptive variation to assess the scale and pattern of local adaptation. Of over 10 k single-nucleotide polymorphisms (SNPs) generated with genotyping-by-sequencing, we found signatures of natural selection by climate or local environment at over 600 SNPs (536 loci), some at multiple spatial scales across multiple analyses. Candidate SNPs identified with gene-environment tests (LFMM) at the rangewide scale also showed elevated associations with climate variables compared to the background at both rangewide and elevational transect scales with gradient forest analysis. Some loci overlap with those detected in other oak species, raising the question of whether the same loci might be involved in local climate adaptation in different congeneric species that inhabit different geographic contexts. Mapping landscape patterns of adaptive versus background genetic variation identified regions of marked local adaptation and suggests nonlinear association of candidate SNPs and environmental variables. Taken together, our results offer robust evidence for novel candidate genes for local climate adaptation at multiple spatial scales.


Assuntos
Quercus , Adaptação Fisiológica/genética , Clima , Genética Populacional , Genômica , Polimorfismo de Nucleotídeo Único/genética , Quercus/genética , Seleção Genética
8.
Int J Health Plann Manage ; 36(6): 2079-2093, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34428325

RESUMO

Improving healthcare performance has become a need for resource optimisation in a field where they are scarce. Activity-Based Costing (ABC) has been applied for more than 30 years to allocate costs and provide information for decision-making. This paper seeks to review previous literature in the health field that analysed this cost system and its new version, TDABC (Time-Driven Activity-Based Costing). Five hundred ninety articles published from 1989 to 2019 were retrieved from Scopus and Medline. The review includes descriptive, relational and content analyses. Results show that the interest in applying these cost systems is growing, especially in journals focusing on the financial aspects of health, policy and planning, and radiology. However, there is a difference in the application of ABC and TDABC. ABC is more related to efficiency and more used in laboratories. In contrast, TDABC is primarily used in hospitals and addressing the value of health rather than cost-effectiveness. On the other hand, the findings suggest that TDABC present greater opportunities for publication compared with ABC. Its progression is higher and gets more citations. The current article contributes to broadening the field's vision and encourages authors for further research.


Assuntos
Atenção à Saúde , Hospitais , Análise Custo-Benefício , Fatores de Tempo
9.
Exp Parasitol ; 206: 107757, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494216

RESUMO

Equine theileriosis is a severe equine disease caused by the protozoan Theileria equi, which is prevalent in tropical and subtropical areas. In this study, a recombinant equi merozoite antigen-2 (rEMA-2) of T. equi was used as an immunogen. Two groups of 10 mice each were divided into control and vaccinated groups. Sixty mares seronegative for theileriosis were divided in two groups, one vaccinated and another group as a control animal. Mice and mares of the vaccinated groups were inoculated with 150 µL of the vaccine containing 50 µg of rEMA-2 and 2 mL of the vaccine containing 200 µg of rEMA-2, respectively, at days 0 and 21. The immunogenicity of rEMA-2 was evaluated by ELISA and fluorescent antibody test (IFAT) using serum from vaccinated mice, mares and antigenicity in naturally infected horse. At every point throughout the ELISA study, there were significant differences between the vaccinated and control groups (p < 0.05). The vaccine induced 3- and 4-fold IgG increases in mice at the 14th and 28th day, respectively, compared to the control group. The horses' IgG dynamics showed a significant (p < 0.05) increase in the total IgG titer as early as day 7, which increased until day 28 at which time a more significant (p < 0.001) IgG titer was observed. In evaluating the isotypes, we observed a trend similar to that of total IgG, where IgG(T) (IgG3-5) were significantly (p < 0.05) more elevated than the other isotypes analyzed, followed by IgGb (IgG4-7) and IgGa (IgG1). Positive fluorescence was detected by IFAT, suggesting that the protein is immunogenic and conserves some epitopes identical to the native T. equi antigens present in the equine blood smear. Thus, our results suggest that rEMA-2 can be a promising vaccinal antigen.


Assuntos
Antígenos de Protozoários/imunologia , Pichia/imunologia , Theileria/imunologia , Análise de Variância , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/biossíntese , Antígenos de Protozoários/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Cavalos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Merozoítos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Distribuição Aleatória , Proteínas Recombinantes/imunologia
10.
Biochim Biophys Acta ; 1863(7 Pt A): 1510-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27085739

RESUMO

Schwann cell migration is essential during the regenerative response to nerve injury, however, the factors that regulate this phenomenon are not yet clear. Here we describe that retinoic acid (RA), whose production and signaling activity are greatly enhanced during nerve regeneration, increases Schwann cell migration. This is accompanied by the up-regulation of NEDD9, a member of the CAS family of scaffold proteins previously implicated in migratory and invasive behavior in gliomas, melanomas and the neural crest cells from which Schwann cells derive. This RA-induced NEDD9 accumulation is due to augmented mRNA levels, as well as an increase of NEDD9 protein stability. Although all NEDD9 phospho-isoforms present in Schwann cells are induced by the retinoid, the hormone also changes its phosphorylation status, thus altering the ratio between the different isoforms. Silencing NEDD9 in Schwann cells had no effect on basal migratory ability, but completely abrogated RA-induced enhanced migration. Collectively, our results indicate that RA could be a major regulator of Schwann cell migration after nerve injury, thus offering a new insight into peripheral nerve repair.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Movimento Celular/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Processamento de Proteína Pós-Traducional , Células de Schwann/efeitos dos fármacos , Transcrição Gênica , Ativação Transcricional , Tretinoína/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células Cultivadas , Proteínas do Citoesqueleto , Relação Dose-Resposta a Droga , Proteínas com Domínio LIM , Proteínas dos Microfilamentos , Oxigenases de Função Mista , Fosforilação , Estabilidade Proteica , Interferência de RNA , RNA Mensageiro/metabolismo , Ratos , Células de Schwann/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Regulação para Cima
11.
Apoptosis ; 22(7): 920-932, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28409399

RESUMO

Breast cancer is one of the most lethal malignancies for women. Retinoic acid (RA) and double-stranded RNA (dsRNA) are considered signaling molecules with potential anticancer activity. RA, co-administered with the dsRNA mimic polyinosinic-polycytidylic acid (poly(I:C)), synergizes to induce a TRAIL (Tumor-Necrosis-Factor Related Apoptosis-Inducing Ligand)- dependent apoptotic program in breast cancer cells. Here, we report that RA/poly(I:C) co-treatment, synergically, induce the activation of Interferon Regulatory Factor-3 (IRF3) in breast cancer cells. IRF3 activation is mediated by a member of the pathogen recognition receptors, Toll-like receptor-3 (TLR3), since its depletion abrogates IRF3 activation by RA/poly(I:C) co-treatment. Besides induction of TRAIL, apoptosis induced by RA/poly(I:C) correlates with the increased expression of pro-apoptotic TRAIL receptors, TRAIL-R1/2, and the inhibition of the antagonistic receptors TRAIL-R3/4. IRF3 plays an important role in RA/poly(I:C)-induced apoptosis since IRF3 depletion suppresses caspase-8 and caspase-3 activation, TRAIL expression upregulation and apoptosis. Interestingly, RA/poly(I:C) combination synergizes to induce a bioactive autocrine/paracrine loop of type-I Interferons (IFNs) which is ultimately responsible for TRAIL and TRAIL-R1/2 expression upregulation, while inhibition of TRAIL-R3/4 expression is type-I IFN-independent. Our results highlight the importance of IRF3 and type-I IFNs signaling for the pro-apoptotic effects induced by RA and synthetic dsRNA in breast cancer cells.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Fator Regulador 3 de Interferon/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Proteínas Ligadas por GPI/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon Tipo I/genética , RNA de Cadeia Dupla/administração & dosagem , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Membro 10c de Receptores do Fator de Necrose Tumoral/genética , Receptor 3 Toll-Like/genética , Tretinoína/administração & dosagem
12.
J Mol Evol ; 84(2-3): 104-115, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28210761

RESUMO

We screened the genomes of a broad panel of kinetoplastid protists for genes encoding proteins associated with the RNA interference (RNAi) system using probes from the Argonaute (AGO1), Dicer1 (DCL1), and Dicer2 (DCL2) genes of Leishmania brasiliensis and Crithidia fasciculata. We identified homologs for all the three of these genes in the genomes of a subset of these organisms. However, several of these organisms lacked evidence for any of these genes, while others lacked only DCL2. The open reading frames encoding these putative proteins were structurally analyzed in silico. The alignments indicated that the genes are homologous with a high degree of confidence, and three-dimensional structural models strongly supported a functional relationship to previously characterized AGO1, DCL1, and DCL2 proteins. Phylogenetic analysis of these putative proteins showed that these genes, when present, evolved in parallel with other nuclear genes, arguing that the RNAi system genes share a common progenitor, likely across all Kinetoplastea. In addition, the genome segments bearing these genes are highly conserved and syntenic, even among those taxa in which they are absent. However, taxa in which these genes are apparently absent represent several widely divergent branches of kinetoplastids, arguing that these genes were independently lost at least six times in the evolutionary history of these organisms. The mechanisms responsible for the apparent coordinate loss of these RNAi system genes independently in several lineages of kinetoplastids, while being maintained in other related lineages, are currently unknown.


Assuntos
Crithidia fasciculata/genética , DNA de Cinetoplasto/genética , Leishmania braziliensis/genética , Trypanosomatina/genética , Sequência de Aminoácidos/genética , Proteínas Argonautas/genética , Evolução Biológica , DNA de Cinetoplasto/metabolismo , Eucariotos/genética , Evolução Molecular , Genoma/genética , Filogenia , Interferência de RNA/fisiologia , Ribonuclease III/genética , Alinhamento de Sequência/métodos , Sintenia/genética
13.
Chemistry ; 22(5): 1582-6, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26641630

RESUMO

We describe herein a Toll-like receptor 3 (TLR3) targeting delivery system based on mesoporous silica nanoparticles capped with the synthetic double stranded RNA polyinosinic-polycytidylic acid (poly(I:C)) for controlled cargo delivery in SK-BR-3 breast carcinoma cells. Our results show that poly(I:C)-conjugated nanoparticles efficiently targeted breast cancer cells due to dsRNA-TLR3 interaction. Such interaction also triggered apoptotic pathways in SK-BR-3, significantly decreasing cells viability. Poly(I:C) cytotoxic effect in breast carcinoma cells was enhanced by loading nanoparticles' mesopores with the anthracyclinic antibiotic doxorubicin, a commonly used chemotherapeutic agent.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/química , Nanopartículas/química , Poli I-C/química , Poli I-C/farmacologia , RNA de Cadeia Dupla/química , Dióxido de Silício/química , Linhagem Celular Tumoral , Feminino , Humanos , Imunidade Inata , RNA de Cadeia Dupla/farmacologia
14.
Parasitology ; 143(12): 1665-71, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27573677

RESUMO

Effective control of gastrointestinal parasites is necessary in sheep production. The development of anthelmintics resistance is causing the available chemically based anthelmintics to become less effective. Biological control strategies present an alternative to this problem. In the current study, we tested the larvicidal effects of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus larvae. Bacterial suspensions [2 × 108 colony-forming units (CFU) g-1 of the feces] of B. thuringiensis var. israelensis and recombinant Escherichia coli expressing Cry11Aa toxin were added to naturally H. contortus egg-contaminated feces. The larvae were quantified, and significant reductions of 62 and 81% (P < 0·001) were, respectively observed, compared with the control group. A 30 mL bacterial suspension (1 × 108 CFU mL-1) of B. thuringiensis var. israelensis and recombinant E. coli expressing Cry11Aa toxin were then orally administered to lambs naturally infected with H. contortus. Twelve hours after administration, feces were collected and submitted to coprocultures. Significant larvae reductions (P < 0·001) of 79 and 90% were observed respectively compared with the control group. The results suggest that the Cry11Aa toxin of B. thuringiensis var. israelensis is a promising new class of biological anthelmintics for treating sheep against H. contortus.


Assuntos
Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Haemonchus/efeitos dos fármacos , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Bioensaio , Terapia Biológica/métodos , Modelos Animais de Doenças , Endotoxinas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Hemoncose/parasitologia , Hemoncose/terapia , Haemonchus/fisiologia , Proteínas Hemolisinas/genética , Larva/efeitos dos fármacos , Larva/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/toxicidade , Ovinos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
15.
J Clin Lab Anal ; 27(6): 477-80, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24218130

RESUMO

BACKGROUND: The primary test for the laboratory confirmation of measles is immunoglobulin M (IgM) serology. It is therefore important to evaluate new commercial measles IgM immunoassays to ensure high-quality measles diagnostic testing. The purpose of this study was to evaluate the diagnostic performance of LIAISON IgM measles (DiaSorin, Saluggia, Italy), a new automated chemiluminescence immunoassay (CLIA), in comparison with enzyme immunoassay (EIA) Enzygnost (Siemens, Marburg, Germany). METHODS: Sensitivity was examined using a panel of measles laboratory confirmed sera; specificity was addressed by testing sera from healthy populations and subjects with infections that may interfere with measles IgM serology. RESULTS: The diagnostic performances of the two assays were very similar: both Enzygnost EIA and LIAISON CLIA performed with a sensitivity of 93.7% and 98.8%, whereas the specificity was 96.8% and 97.9%, respectively. CONCLUSION: We concluded that LIAISON IgM measles can be a good alternative to the other immunoassay for laboratory measles confirmation.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , Medições Luminescentes/métodos , Sarampo/diagnóstico , Virologia/métodos , Humanos , Sarampo/imunologia , Sarampo/virologia , Sensibilidade e Especificidade
16.
PLoS One ; 18(11): e0293480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917781

RESUMO

This research proposes: (i) analyze push and pull motivations in insular marine protected areas, and (ii) determine their effects on tourists' satisfaction, positive recommendations and loyalty in terms of returning. The study was conducted in the Galápagos Islands in Ecuador; a renowned marine protected area with a National Park being a Natural Heritage Site of Humanity by UNESCO. An exploratory (EFA) and confirmatory factor analysis (CFA), followed by a stepwise multiple regression analysis applied on a sample of 407 tourists in the Galápagos Islands showed four push and pull motivational factors in this destination: "passive marine," "active marine," "novelty and escape," and "social relations". "Passive marine" and "social relations" were the most prominent factors influencing tourist satisfaction and return intentions. Moreover, "passive marine" and "novelty and escape " highly influenced visitors' intention to recommend and give positive feedback about this place. These findings constitute action guides for the adequate management of marine protected areas.


Assuntos
Intenção , Motivação , Equador , Satisfação Pessoal , Análise de Regressão
17.
Surg Oncol ; 51: 101997, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832278

RESUMO

BACKGROUND: The treatment of choice for retroperitoneal soft tissue sarcomas (RPS) is surgical resection; the outcomes with more radical surgeries, notably compartmental resection, remains a subject of debate. Arguments against it, include the complexity of the technique and high morbidity. MATERIALS AND METHODS: A retrospective analysis of cases treated in a single center from January 2010 to December 2019 is presented. Two time periods were evaluated: 2010-2015 and 2016-2019, corresponding to before and after the implementation of routine compartmentectomy. We evaluated the short- and long-term outcomes of compartmental resection compared to limited surgeries through a multivariate analysis of prognostic factors. RESULTS: A total of 176 cases were included, of which 102 met the inclusion criteria. The sex distribution was similar. The average age was 52.9 years, and the average tumor size was 24.5 cm. The most frequent histology was liposarcoma (65.7%), followed by leiomyosarcoma (12.7%), and malignant peripheral nerve sheath tumor (8.8%). The median follow-up period was 40 months. We found a lower local recurrence in the group treated in the recent period (compartmentectomy) 42.3% vs 20% p = 0.007. The median overall survival (OS) was 38.7 months, and there was no difference in distant recurrence between the two time periods. Postoperative morbidity was higher in the recent period (25% vs 10% p 0.041), with no difference in 30-day mortality. CONCLUSIONS: The implementation of extensive surgery, specifically compartmentectomy, for retroperitoneal sarcomas has been linked to reduced local recurrence. We recommend considering this surgical approach for RPS in alignment with current expert consensus guidelines, as highlighted by the updated TARPSWG consensus.


Assuntos
Leiomiossarcoma , Lipossarcoma , Neoplasias Retroperitoneais , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sarcoma/patologia , Leiomiossarcoma/patologia , Lipossarcoma/patologia , Encaminhamento e Consulta , Neoplasias Retroperitoneais/cirurgia , Neoplasias Retroperitoneais/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico
18.
Rev Biol Trop ; 60(1): 1-10, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22458206

RESUMO

The tropical dry forest is a greatly endangered ecosystem, from which Jacaratia mexicana is a native tree. With the aim to assess the levels of genetic variation and population structure, four wild populations of J. mexicana were studied in the Sierra de Huautla Biosphere Reserve, Morelos, Mexico. For this, DNA was extracted from 159 individuals and were amplified with six random primers using the Random Amplified Polymorphic DNA (RAPD). A total of 54 bands were obtained, of which 50 (92.6%) were polymorphic. The total genetic diversity found within the four populations was 0.451 when estimated by Shannon's index. An AMOVA analysis showed that 84% of the total genetic variation was found within populations and 16% was among populations. The UPGMA dendrogram showed that all individuals from one of the populations (Huaxtla) formed one distinct genetic group, while the rest of the individuals did not cluster according to population. A Mantel test did not show an association between genetic and geographical distances among populations (r=0.893, p=0.20). A Bayesian cluster analysis performed with STRUCTURE, showed that the most probable number of genetic groups in the data was four (K=4), and confirmed the distinctness of Huaxtla population. Our results showed that important genetic differentiation among populations can occur even at this small geographic scale and this has to be considered in conservation actions for this genetic resource.


Assuntos
Caricaceae/genética , Variação Genética , Árvores/genética , Teorema de Bayes , DNA de Plantas/análise , México , Técnica de Amplificação ao Acaso de DNA Polimórfico
19.
Sci Rep ; 12(1): 9353, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672429

RESUMO

Notwithstanding the fact that streptomycetes are overlooked in clinical laboratories, studies describing their occurrence in disease and potential pathogenicity are emerging. Information on their species diversity in clinical specimens, aetiology and appropriate therapeutic treatment is scarce. We identified and evaluated the antibiotic susceptibility profile of 84 Streptomyces clinical isolates from the Czech Republic. In the absence of appropriate disk diffusion (DD) breakpoints for antibiotic susceptibility testing (AST) of Streptomyces spp., we determined DD breakpoints by correlation with the broth microdilution method and by the distribution of zone diameters among isolates. Correlation accuracy was high for 9 antibiotics, leading to the establishment of the most valid DD breakpoints for Streptomyces antibiotic susceptibility evaluation so far. Clinical strains belonged to 17 different phylotypes dominated by a cluster of strains sharing the same percentage of 16S rRNA gene sequence identity with more than one species (S. albidoflavus group, S. hydrogenans, S. resistomycificus, S. griseochromogenes; 70% of isolates). AST results showed that Streptomyces exhibited intrinsic resistance to penicillin, general susceptibility to amikacin, gentamycin, vancomycin and linezolid, and high percentage of susceptibility to tetracyclines and clarithromycin. For the remaining antibiotics, AST showed inter- and intra-species variations when compared to available literature (erythromycin, trimethoprim-sulfamethoxazole), indicating a region-dependent rather than species-specific patterns.


Assuntos
Streptomyces , Antibacterianos/farmacologia , Linezolida , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Streptomyces/genética
20.
Heliyon ; 8(10): e10867, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36211999

RESUMO

The COVID-19 pandemic has prompted the re-emergence of staycations to the fore, as many people were forced to spend their vacations at or close to home due to travel restrictions. This phenomenon first went mainstream during the 2008 financial crisis, and has now been further accelerated by the COVID-19 pandemic. This study investigated the growth and practice of staycations during the first two years of the pandemic by analyzing social media and internet search data using Latent Dirichlet Allocation (LDA) topic modeling and Google Trends analytics. Key findings suggest that, while spatially close to home, people tried to achieve a psychological distance away from home. This was demonstrated by a strong global search interest in spending staycations at hotels close to home. The optimal LDA topic model produced 38 topics which were classified under four aggregate dimensions of antecedents, attributes, activities, and consequences of staycations. The findings provide useful insights to managers and policymakers on boosting revenue through this practice, and the role of staycations in promoting leisure activities close to home and sustainable tourism.

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