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71.
Ian W. Pray Dallas J. Swanson Viterbo Ayvar Claudio Muro Luz M. Moyano Armando E. Gonzalez Hector H. Garcia Seth E. O’Neal Cysticercosis Working Group in Peru 《PLoS neglected tropical diseases》2016,10(4)
Background
Taenia solium, a parasitic cestode that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. T. solium eggs are released into the environment through the stool of humans infected with an adult intestinal tapeworm (a condition called taeniasis), and cause cysticercosis when ingested by pigs or other humans. A control strategy to intervene within high-risk foci in endemic communities has been proposed as an alternative to mass antihelminthic treatment. In this ring strategy, antihelminthic treatment is targeted to humans and pigs residing within a 100 meter radius of a pig heavily-infected with cysticercosis. Our aim was to describe the roaming ranges of pigs in this region, and to evaluate whether the 100 meter radius rings encompass areas where risk factors for T. solium transmission, such as open human defecation and dense pig activity, are concentrated.Methodology/Principal Findings
In this study, we used Global Positioning System (GPS) devices to track pig roaming ranges in two rural villages of northern Peru. We selected 41 pigs from two villages to participate in a 48-hour tracking period. Additionally, we surveyed all households to record the locations of open human defecation areas. We found that pigs spent a median of 82.8% (IQR: 73.5, 94.4) of their time roaming within 100 meters of their homes. The size of home ranges varied significantly by pig age, and 93% of the total time spent interacting with open human defecation areas occurred within 100 meters of pig residences.Conclusions/Significance
These results indicate that 100 meter radius rings around heavily-infected pigs adequately capture the average pig’s roaming area (i.e., home range) and represent an area where the great majority of exposure to human feces occurs. 相似文献72.
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76.
Francesca Ascenzi Laura Barberi Gabriella Dobrowolny Aline Villa Nova Bacurau Carmine Nicoletti Emanuele Rizzuto Nadia Rosenthal Bianca Maria Scicchitano Antonio Musar 《Aging cell》2019,18(3)
The decline in skeletal muscle mass and strength occurring in aging, referred as sarcopenia, is the result of many factors including an imbalance between protein synthesis and degradation, changes in metabolic/hormonal status, and in circulating levels of inflammatory mediators. Thus, factors that increase muscle mass and promote anabolic pathways might be of therapeutic benefit to counteract sarcopenia. Among these, the insulin‐like growth factor‐1 (IGF‐1) has been implicated in many anabolic pathways in skeletal muscle. IGF‐1 exists in different isoforms that might exert different role in skeletal muscle. Here we study the effects of two full propeptides IGF‐1Ea and IGF‐1Eb in skeletal muscle, with the aim to define whether and through which mechanisms their overexpression impacts muscle aging. We report that only IGF‐1Ea expression promotes a pronounced hypertrophic phenotype in young mice, which is maintained in aged mice. Nevertheless, examination of aged transgenic mice revealed that the local expression of either IGF‐1Ea or IGF‐1Eb transgenes was protective against age‐related loss of muscle mass and force. At molecular level, both isoforms activate the autophagy/lysosome system, normally altered during aging, and increase PGC1‐α expression, modulating mitochondrial function, ROS detoxification, and the basal inflammatory state occurring at old age. Moreover, morphological integrity of neuromuscular junctions was maintained and preserved in both MLC/IGF‐1Ea and MLC/IGF‐1Eb mice during aging. These data suggest that IGF‐1 is a promising therapeutic agent in staving off advancing muscle weakness. 相似文献
77.
Claudio Franceschi Paolo Garagnani Nomie Gensous Maria Giulia Bacalini Maria Conte Stefano Salvioli 《Aging cell》2019,18(3)
Down syndrome (DS) has been proposed by George Martin as a segmental progeroid syndrome since 1978. In fact, DS persons suffer from several age‐associated disorders much earlier than euploid persons. Furthermore, a series of recent studies have found that DS persons display elevated levels of age biomarkers, thus supporting the notion that DS is a progeroid trait. Nowadays, due to the progressive advancements in social inclusion processes and medical assistance, DS persons live much longer than in the past; therefore, the early‐onset health problems of these persons are becoming an urgent and largely unmet social and medical burden. In particular, the most important ailment of DS persons is the accelerated cognitive decline that starts when they reach about 40 years of age. This decline can be at least in part counteracted by multi‐systemic approaches including early‐onset cognitive training, physical activity, and psychosocial assistance. However, no pharmacological treatment is approved to counteract this decline. According to the most advanced conceptualization of Geroscience, tackling the molecular mechanisms underpinning the aging process should be a smart/feasible strategy to combat and/or delay the great majority of age‐related diseases, including cognitive decline. We think that a debate is needed urgently on if (and how) this strategy could be integrated in protocols to face DS‐associated dementia and overall unhealthy aging. In particular we propose that, on the basis of data obtained in different clinical settings, metformin is a promising candidate that could be exploited to counteract cognitive decline in DS. 相似文献
78.
Pedro Barbacena Marie Ouarn Jody J. Haigh Francisca F. Vasconcelos Anna Pezzarossa Claudio A. Franco 《Genesis (New York, N.Y. : 2000)》2019,57(6)
Cell migration is essential during development, regeneration, homeostasis, and disease. Depending on the microenvironment, cells use different mechanisms to migrate. Yet, all modes of migration require the establishment of an intracellular front–rear polarity axis for directional movement. Although front–rear polarity can be easily identified in in vitro conditions, its assessment in vivo by live‐imaging is challenging due to tissue complexity and lack of reliable markers. Here, we describe a novel and unique double fluorescent reporter mouse line to study front–rear cell polarity in living tissues, called GNrep. This mouse line simultaneously labels Golgi complexes and nuclei allowing the assignment of a nucleus‐to‐Golgi axis to each cell, which functions as a readout for cell front–rear polarity. As a proof‐of‐principle, we validated the efficiency of the GNrep line using an endothelial‐specific Cre mouse line. We show that the GNrep labels the nucleus and the Golgi apparatus of endothelial cells with very high efficiency and high specificity. Importantly, the features of fluorescent intensity and localization for both mCherry and eGFP fluorescent intensity and localization allow automated segmentation and assignment of polarity vectors in complex tissues, making GNrep a great tool to study cell behavior in large‐scale automated analyses. Altogether, the GNrep mouse line, in combination with different Cre recombinase lines, is a novel and unique tool to study of front–rear polarity in mice, both in fixed tissues or in intravital live imaging. This new line will be instrumental to understand cell migration and polarity in development, homeostasis, and disease. 相似文献
79.
Francielly Cristina Machado Renata Prandini Adum de Matos Fernando Lucas Primo Antonio Claudio Tedesco Paula Rahal Marília Freitas Calmon 《Bioorganic & medicinal chemistry》2019,27(9):1882-1890
Curcumin, a natural compound has several antineoplastic activities and is a promising natural photosensitizer used in photodynamic therapy. However, its low solubility in physiological medium limit the clinical use of curcumin. This study aimed to analyze the action of curcumin-nanoemulsion, a new and well-designed Drug Delivery System (DDS+) molecule, used as a photosensitizing agent in photodynamic therapy in an in vitro breast cancer model, MCF-7 cells. The empty nanoemulsion fulfils all necessary requirements to be an excellent DDS. Furthermore, the use of curcumin-nanoemulsion in photodynamic therapy resulted in a high phototoxic effect after activation at 440?nm, decreasing to <10% viable tumor cells after two irradiations and increasing the reactive oxygen species (ROS) production. The use of curcumin-nanoemulsion associated with photodynamic therapy resulted in an increase in the levels of caspase 3/7 activity for the studied MCF-7 cell model, indicating that this therapy triggers a cascade of events that lead to cell death, such as cellular apoptosis. In conclusion, curcumin-nanoemulsion proved to be efficient as a photosensitizing agent, had phototoxic effects, significantly decreased the proliferation of MCF-7 cells and stimulating the ROS production in combination with photodynamic therapy, so, this formulation has a great potential for use in treatment of breast cancer. 相似文献