47 research outputs found
Strigolactone analogs act as new anti-cancer agents in inhibition of breast cancer in xenograft model
Strigolactones (SLs) are a novel class of plant hormones. Previously, we found that analogs of SLs induce growth arrest and apoptosis in breast cancer cell lines. These compounds also inhibited the growth of breast cancer stem cell enriched-mammospheres with increased potency. Furthermore, strigolactone analogs inhibited growth and survival of colon, lung, prostate, melanoma, osteosarcoma and leukemia cancer cell lines. To further examine the anti-cancer activity of SLs in vivo, we have examined their effects on growth and viability of MDA-MB-231 tumor xenografts model either alone or in combination with paclitaxel. We show that strigolactone act as new anti-cancer agents in inhibition of breast cancer in xenograft model. In addition we show that SLs affect the integrity of the microtubule network and therefore may inhibit the migratory phenotype of the highly invasive breast cancer cell lines that were examined
Avaliação do conforto térmico no edifício v2 da Universidade de Passo Fundo - Brasil/Evaluation of thermal comfort on the building v2 of Univeristy of Passo Fundo - Brazil
O conforto térmico em um edifício é importante para o bem-estar dos usuários e para o bom desempenho das atividades desenvolvidas dentro do ambiente construído. Portanto, é necessária a manutenção dos níveis adequados de temperatura e umidade relativa para garantir a eficiência energética e minimizar o uso de sistemas de condicionamento térmico ativos. O objeto de estudo faz parte de um projeto de pesquisa desenvolvido na Universidade de Passo Fundo - UPF, e tem como elemento de análise o edifício V2. Concomitantemente com a ocupação do prédio em 2015, as análises verificam as condições térmicas das salas de aula através das variáveis de temperatura de bulbo seco e umidade relativa por meio de Data-Loggers. Os dados obtidos a partir das medições permitiram uma compilação de diagramas temporais e sazonais. Além disso, as informações foram analisadas com base nas características e no desempenho da envoltória do edifício. Dessa forma, observou-se que as sensações térmicas dos ambientes internos, considerando a complexidade climática de Passo Fundo, indicam vários períodos de desconforto. Com base no diagnóstico dos dados, buscam-se melhorias nos ambientes universitários, para alcançar um melhor desempenho acadêmico dentro da estrutura em análise, bem como todo o parque construído
Impact of changing climate on bryophyte contributions to terrestrial water, carbon, and nitrogen cycles
Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes influence global biogeochemical cycles, and we highlight that while some aspects of global change represent critical tipping points for survival, bryophytes may also buffer many ecosystems from change due to their capacity for water, C, and N uptake and storage. However, as the thresholds of resistance of bryophytes to temperature and precipitation regime changes are mostly unknown, it is challenging to predict how long this buffering capacity will remain functional. Furthermore, as ecosystems shift their global distribution in response to changing climate, the size of different bryophyte-influenced biomes will change, resulting in shifts in the magnitude of bryophyte impacts on global ecosystem functions
What are the type, direction, and strength of species, community, and ecosystem responses to warming in aquatic mesocosm studies and their dependency on experimental characteristics? A systematic review protocol
Background
Mesocosm experiments have become increasingly popular in climate change research as they bridge the gap between small-scale, less realistic, microcosm experiments, and large-scale, more complex, natural systems. Characteristics of aquatic mesocosm designs (e.g., mesocosm volume, study duration, and replication) vary widely, potentially affecting the magnitude and direction of effect sizes measured in experiments. In this global systematic review we aim to identify the type, direction and strength of climate warming effects on aquatic species, communities and ecosystems in mesocosm experiments. Furthermore, we will investigate the context-dependency of the observed effects on several a priori determined effect moderators (ecological and methodological). Our conclusions will provide recommendations for aquatic scientists designing mesocosm experiments, as well as guidelines for interpretation of experimental results by scientists, policy-makers and the general public.
Methods
We will conduct a systematic search using multiple online databases to gather evidence from the scientific literature on the effects of warming experimentally tested in aquatic mesocosms. Data from relevant studies will be extracted and used in a random effects meta-analysis to estimate the overall effect sizes of warming experiments on species performance, biodiversity and ecosystem functions. Experimental characteristics (e.g., mesocosm size and shape, replication-level, experimental duration and design, biogeographic region, community type, crossed manipulation) will be further analysed using subgroup analyses
Tolerogenic Dendritic Cells on Transplantation: Immunotherapy Based on Second Signal Blockage
Dendritic cells (DCs), the most important professional antigen-presenting cells (APC), play crucial role in both immunity and tolerance. It is well known that DCs are able to mount immune responses against foreign antigens and simultaneously tolerate self-antigens. Since DCs can be modulated depending on the surrounding microenvironment, they can act as a bridge between innate and adaptive immunity. However, the mechanisms that support this dual role are not entirely clear. Recent studies have shown that DCs can be manipulated ex vivo in order to trigger their tolerogenic profile, what can be a tool to be used in clinical trials aiming the treatment of various diseases and the prevention of transplant rejection. In this sense, the blockage of costimulatory molecules on DC, in the attempt of inhibiting the second signal in the immunological synapse, can be considered as one of the main strategies under development. This review brings an update on current therapies using tolerogenic dendritic cells modulated with costimulatory blockers with the aim of reducing transplant rejection. However, although there are current clinical trials using tolerogenic DC to treat allograft rejection, the actual challenge is to modulate these cells in order to maintain a permanent tolerogenic profile
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Larval exposure to predator cues alters immune function and response to a fungal pathogen in post-metamorphic wood frogs
For the past several decades, amphibian populations have been decreasing
around the globe at an unprecedented rate. Batrachochytrium dendrobatidis (Bd), the fungal
pathogen that causes chytridiomycosis in amphibians, is contributing to amphibian declines.
Natural and anthropogenic environmental factors are hypothesized to contribute to these
declines by reducing the immunocompetence of amphibian hosts, making them more
susceptible to infection. Antimicrobial peptides (AMPs) produced in the granular glands of a
frog’s skin are thought to be a key defense against Bd infection. These peptides may be a
critical immune defense during metamorphosis because many acquired immune functions are
suppressed during this time. To test if stressors alter AMP production and survival of frogs
exposed to Bd, we exposed wood frog (Lithobates sylvaticus) tadpoles to the presence or
absence of dragonfly predator cues crossed with a single exposure to three nominal
concentrations of the insecticide malathion (0, 10, or 100 parts per billion [ppb]). We then
exposed a subset of post-metamorphic frogs to the presence or absence of Bd zoospores and
measured frog survival. Although predator cues and malathion had no effect on survival or
size at metamorphosis, predator cues increased the time to metamorphosis by 1.5 days and
caused a trend of a 20% decrease in hydrophobic skin peptides. Despite this decrease in
peptides determined shortly after metamorphosis, previous exposure to predator cues
increased survival in both Bd-exposed and unexposed frogs several weeks after metamorphosis.
These results suggest that exposing tadpoles to predator cues confers fitness benefits later
in life.Keywords: immunosuppression,
AchE inhibitor,
chytridiomycosis,
disease ecology,
brevinin,
emerging infectious disease,
Batrachochytrium dendrobatidis,
temporin,
Lithobates sylvaticus,
indirect effect
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Cognitive rehabilitation, self-management, psychotherapeutic and caregiver support interventions in progressive neurodegenerative conditions: a scoping review
BACKGROUND: Despite their potentially significant impact, cognitive disability may be overlooked in a number of progressive neurodegenerative conditions, as other difficulties dominate the clinical picture.
OBJECTIVE: We examined the extent, nature and range of the research evidence relating to cognitive rehabilitation, self-management, psychotherapeutic and caregiver support interventions in Parkinsonian disorders, multiple sclerosis (MS), frontotemporal dementias (FTD), motor neuron disease and Huntington’s disease.
METHODS: Scoping review based on searches of MEDLINE and CINAHL up to 15 March 2016.
RESULTS: We included 140 eligible papers. Over half of the studies, and almost all the randomised controlled trials, related to MS, while a number of single case studies described interventions for people with FTD. CR interventions addressed functional ability, communication and interaction, behaviour or memory. The majority of psychotherapy interventions involved cognitive behavioural therapy for depression or anxiety. Self-management interventions were mainly available for people with MS. There were few reports of interventions specific to caregivers. Numerous methodological challenges were identified.
CONCLUSIONS: The limited range of studies for all conditions except MS suggests a need firstly to synthesise systematically the available evidence across conditions and secondly to develop well-designed studies to provide evidence about the effectiveness of CR and other psychological interventions
Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation and function and EBV immunity
Background Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphoinositide 3-kinase (PI3K), result in hyperactivation of the PI3K–AKT–mechanistic target of rapamycin pathway and underlie a novel inborn error of immunity. Affected subjects exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or cytomegalovirus infection, and increased incidence of B-cell lymphoproliferation, lymphoma, or both. Mechanisms underlying disease pathogenesis remain unknown. Objective Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in patients with PIK3CD GOF mutations, identify key molecules required for cell-mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this and other EBV-opathies. Methods We studied the consequences of PIK3CD GOF mutations on the generation, differentiation, and function of CD8+ T cells and natural killer (NK) cells, which are implicated in host defense against infection with herpesviruses, including EBV. Results PIK3CD GOF total and EBV-specific CD8+ T cells were skewed toward an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion and increased susceptibility to reactivation-induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF mutations. NK cells in patients with PIK3CD GOF mutations also exhibited perturbed expression of differentiation-associated molecules. Both CD8+ T and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, programmed death ligand 1/2, and CD70. Conclusions PIK3CD GOF mutations aberrantly induce exhaustion, senescence, or both and impair cytotoxicity of CD8+ T and NK cells. These defects might contribute to clinical features of affected subjects, such as impaired immunity to herpesviruses and tumor surveillance
Pathogenic SPTBN1 variants cause an autosomal dominant neurodevelopmental syndrome
SPTBN1 mutations cause a neurodevelopmental syndrome characterized by intellectual disability, language and motor delays, autism, seizures and other features. The variants disrupt beta II-spectrin function and disturb cytoskeletal organization and dynamics. SPTBN1 encodes beta II-spectrin, the ubiquitously expressed beta-spectrin that forms micrometer-scale networks associated with plasma membranes. Mice deficient in neuronal beta II-spectrin have defects in cortical organization, developmental delay and behavioral deficiencies. These phenotypes, while less severe, are observed in haploinsufficient animals, suggesting that individuals carrying heterozygous SPTBN1 variants may also show measurable compromise of neural development and function. Here we identify heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays;mild to severe intellectual disability;autistic features;seizures;behavioral and movement abnormalities;hypotonia;and variable dysmorphic facial features. We show that these SPTBN1 variants lead to effects that affect beta II-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. Our studies define SPTBN1 variants as the genetic basis of a neurodevelopmental syndrome, expand the set of spectrinopathies affecting the brain and underscore the critical role of beta II-spectrin in the central nervous system
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Evaluation of the cost and effectiveness of diverse recruitment methods for a genetic screening study
Purpose: Recruitment of participants from diverse backgrounds is crucial to the generalizability of genetic research, but has proven challenging. We retrospectively evaluated recruitment methods used for a study on return of genetic results.
Methods: The costs of study design, development, and participant enrollment were calculated, and the characteristics of the participants enrolled through the seven recruitment methods were examined.
Results: A total of 1118 participants provided consent, a blood sample, and questionnaire data. The estimated cost across recruitment methods ranged from 1666 per participant and required a large recruitment team. Recruitment methods using flyers and staff networks were the most cost-efficient and resulted in the highest completion rate. Targeted sampling that emphasized the importance of Latino/a participation, utilization of translated materials, and in-person recruitments contributed to enrolling a demographically diverse sample.
Conclusions: Although all methods were deployed in the same hospital or neighborhood and shared the same staff, each recruitment method was different in terms of cost and characteristics of the enrolled participants, suggesting the importance of carefully choosing the recruitment methods based on the desired composition of the final study sample. This analysis provides information about the effectiveness and cost of different methods to recruit adults for genetic research