77 research outputs found
An N-Acetyl Cysteine Ruthenium Tricarbonyl Conjugate Enables Simultaneous Release of CO and Ablation of Reactive Oxygen Species.
We have designed and synthesised a [Ru(CO)3 Cl2 (NAC)] pro-drug that features an N-acetyl cysteine (NAC) ligand. This NAC carbon monoxide releasing molecule (CORM) conjugate is able to simultaneously release biologically active CO and to ablate the concurrent formation of reactive oxygen species (ROS). Complexes of the general formulae [Ru(CO)3 (L)3 ](2+) , including [Ru(CO)3 Cl(glycinate)] (CORM-3), have been shown to produce ROS through a water-gas shift reaction, which contributes significantly, for example, to their antibacterial activity. In contrast, NAC-CORM conjugates do not produce ROS or possess antibacterial activity. In addition, we demonstrate the synergistic effect of CO and NAC both for the inhibition of nitric oxide (formation) and in the expression of tumour-necrosis factor (TNF)-α. This work highlights the advantages of combining a CO-releasing scaffold with the anti-oxidant and anti-inflammatory drug NAC in a unique pro-drug.We thank the EU (Marie Curie CIG to G.J.L.B.), FCT Portugal (FCT Investigator to G.J.L.B.; SFRH/BPD/95253/2013 to J.D.S.) and the EPSRC for funding. The NMR spectrometers are part of The National NMR Facility, supported by Fundação para a Ciência e a Tecnologia (RECI/BBB-BQB/0230/2012). G.J.L.B. is a Royal Society University Research Fellow.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/chem.20150247
A Mouse Model of Pulmonary Metastasis from Spontaneous Osteosarcoma Monitored In Vivo by Luciferase Imaging
BACKGROUND: Osteosarcoma (OSA) is lethal when metastatic after chemotherapy and/or surgical treatment. Thus animal models are necessary to study the OSA metastatic spread and to validate novel therapies able to control the systemic disease. We report the development of a syngeneic (Balb/c) murine OSA model, using a cell line derived from a spontaneous murine tumor. METHODOLOGY: The tumorigenic and metastatic ability of OSA cell lines were assayed after orthotopic injection in mice distal femur. Expression profiling was carried out to characterize the parental and metastatic cell lines. Cells from metastases were propagated and engineered to express Luciferase, in order to follow metastases in vivo. PRINCIPAL FINDINGS: Luciferase bioluminescence allowed to monitor the primary tumor growth and revealed the appearance of spontaneous pulmonary metastases. In vivo assays showed that metastasis is a stable property of metastatic OSA cell lines after both propagation in culture and luciferase trasduction. When compared to parental cell line, both unmodified and genetically marked metastatic cells, showed comparable and stable differential expression of the enpp4, pfn2 and prkcd genes, already associated to the metastatic phenotype in human cancer. CONCLUSIONS: This OSA animal model faithfully recapitulates some of the most important features of the human malignancy, such as lung metastatization. Moreover, the non-invasive imaging allows monitoring the tumor progression in living mice. A great asset of this model is the metastatic phenotype, which is a stable property, not modifiable after genetic manipulation
Estimating how inflated or obscured effects of climate affect forecasted species distribution
Climate is one of the main drivers of species distribution. However, as different environmental factors tend to co-vary, the
effect of climate cannot be taken at face value, as it may be either inflated or obscured by other correlated factors. We used
the favourability models of four species (Alytes dickhilleni, Vipera latasti, Aquila fasciata and Capra pyrenaica) inhabiting
Spanish mountains as case studies to evaluate the relative contribution of climate in their forecasted favourability by using
variation partitioning and weighting the effect of climate in relation to non-climatic factors. By calculating the pure effect of
the climatic factor, the pure effects of non-climatic factors, the shared climatic effect and the proportion of the pure effect of
the climatic factor in relation to its apparent effect (r), we assessed the apparent effect and the pure independent effect of
climate. We then projected both types of effects when modelling the future favourability for each species and combination
of AOGCM-SRES (two Atmosphere-Ocean General Circulation Models: CGCM2 and ECHAM4, and two Special Reports on
Emission Scenarios (SRES): A2 and B2). The results show that the apparent effect of climate can be either inflated (overrated)
or obscured (underrated) by other correlated factors. These differences were species-specific; the sum of favourable areas
forecasted according to the pure climatic effect differed from that forecasted according to the apparent climatic effect by
about 61% on average for one of the species analyzed, and by about 20% on average for each of the other species. The pure
effect of future climate on species distributions can only be estimated by combining climate with other factors. Transferring
the pure climatic effect and the apparent climatic effect to the future delimits the maximum and minimum favourable areas
forecasted for each species in each climate change scenario.Ministerio de Ciencia e Innovación and FEDER (project CGL2009-11316/BOS). D. Romero is a PhD student at the University of Malaga with a grant of the Ministerio de Educacio´n y Ciencia (AP 2007-03633
Functional Characterization of an Aspergillus fumigatus Calcium Transporter (PmcA) that Is Essential for Fungal Infection
Aspergillus fumigatus is a primary and opportunistic pathogen, as well as a major allergen, of mammals. The Ca+2-calcineurin pathway affects virulence, morphogenesis and antifungal drug action in A. fumigatus. Here, we investigated three components of the A. fumigatus Ca+2-calcineurin pathway, pmcA,-B, and -C, which encode calcium transporters. We demonstrated that CrzA can directly control the mRNA accumulation of the pmcA-C genes by binding to their promoter regions. CrzA-binding experiments suggested that the 5′-CACAGCCAC-3′ and 5′-CCCTGCCCC-3′ sequences upstream of pmcA and pmcC genes, respectively, are possible calcineurin-dependent response elements (CDREs)-like consensus motifs. Null mutants were constructed for pmcA and -B and a conditional mutant for pmcC demonstrating pmcC is an essential gene. The ΔpmcA and ΔpmcB mutants were more sensitive to calcium and resistant to manganese and cyclosporin was able to modulate the sensitivity or resistance of these mutants to these salts, supporting the interaction between calcineurin and the function of these transporters. The pmcA-C genes have decreased mRNA abundance into the alveoli in the ΔcalA and ΔcrzA mutant strains. However, only the A. fumigatus ΔpmcA was avirulent in the murine model of invasive pulmonary aspergillosis
Integrating sustainable hunting in biodiversity protection in central Africa: Hot spots, weak spots, and strong spots
© 2014 Fa et al. Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting. Copyright
Venous hemodynamics in neurological disorders: an analytical review with hydrodynamic analysis.
Venous abnormalities contribute to the pathophysiology of several neurological conditions. This paper reviews the literature regarding venous abnormalities in multiple sclerosis (MS), leukoaraiosis, and normal-pressure hydrocephalus (NPH). The review is supplemented with hydrodynamic analysis to assess the effects on cerebrospinal fluid (CSF) dynamics and cerebral blood flow (CBF) of venous hypertension in general, and chronic cerebrospinal venous insufficiency (CCSVI) in particular.CCSVI-like venous anomalies seem unlikely to account for reduced CBF in patients with MS, thus other mechanisms must be at work, which increase the hydraulic resistance of the cerebral vascular bed in MS. Similarly, hydrodynamic changes appear to be responsible for reduced CBF in leukoaraiosis. The hydrodynamic properties of the periventricular veins make these vessels particularly vulnerable to ischemia and plaque formation.Venous hypertension in the dural sinuses can alter intracranial compliance. Consequently, venous hypertension may change the CSF dynamics, affecting the intracranial windkessel mechanism. MS and NPH appear to share some similar characteristics, with both conditions exhibiting increased CSF pulsatility in the aqueduct of Sylvius.CCSVI appears to be a real phenomenon associated with MS, which causes venous hypertension in the dural sinuses. However, the role of CCSVI in the pathophysiology of MS remains unclear
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Implementing a telehealth prehabilitation education session for patients preparing for major cancer surgery
Background: Prehabilitation services assist patients in preparing for surgery, yet access to these services are often limited by geographical factors. Enabling rural and regional patients to access specialist surgical prehabilitation support with the use of telehealth technology has the potential to overcome health inequities and improve post-operative outcomes.
Aim: To evaluate the current and likely future impact of a telehealth preoperative education package for patients preparing for major abdominal cancer surgery.
Methods: A telehealth alternative to a hospital based pre-operative education session was developed and implemented at a dedicated cancer hospital. Adult patients (≥18 years) scheduled for elective major cancer surgery were offered this telehealth alternative. Impact evaluation was conducted using the RE-AIM framework.
Results: To date, 35 participants have consented to participate in the study. Thirty-one participants attended the intervention; 24 (69%) residing in rural or regional areas. Twenty-four (77%) reported that if given a choice they would prefer the online session as opposed to attending the hospital in person. The majority (97%) reported they would recommend the intervention to others preparing for surgery. Session information was recalled by all 26 participants and 77% of participants reported acting on recommendations 2 weeks after the session. Lessons learnt and recommendations for providers implementing similar programs are reported.
Conclusion: Telehealth alternatives to hospital based pre-operative education are well received by patients preparing for major cancer surgery. We make seven recommendations to improve implementation. Further evaluation of implementation strategies alongside clinical effectiveness in future studies is essential
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