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1.
JAMES DWYER 《Bioethics》2009,23(9):497-502
In this paper, I explore one way to bring bioethics and environmental ethics closer together. I focus on a question at the interface of health, sustainability, and justice: How well does a society promote health with the use of no more than a just share of environmental capacity? To address this question, I propose and discuss a mode of assessment that combines a measurement of population health, an estimate of environmental sustainability, and an assumption about what constitutes a fair or just share. This mode of assessment provides an estimate of the just and sustainable life expectancy of a population. It could be used to monitor how well a particular society promotes health within just environmental limits. It could also serve as a source of information that stakeholders use when they deliberate about programs, policies, and technologies. The purpose of this work is to focus attention on an ethical task: the need to fashion institutions and forms of life that promote health in ways that recognize the claims of sustainability and justice.  相似文献   

2.
Since the 1980s, Islamic scholars and medical experts have used the tools of Islamic law to formulate ethico‐legal opinions on brain death. These assessments have varied in their determinations and remain controversial. Some juridical councils such as the Organization of Islamic Conferences' Islamic Fiqh Academy (OIC‐IFA) equate brain death with cardiopulmonary death, while others such as the Islamic Organization of Medical Sciences (IOMS) analogize brain death to an intermediate state between life and death. Still other councils have repudiated the notion entirely. Similarly, the ethico‐legal assessments are not uniform in their acceptance of brain‐stem or whole‐brain criteria for death, and consequently their conceptualizations of, brain death. Within the medical literature, and in the statements of Muslim medical professional societies, brain death has been viewed as sanctioned by Islamic law with experts citing the aforementioned rulings. Furthermore, health policies around organ transplantation and end‐of‐life care within the Muslim world have been crafted with consideration of these representative religious determinations made by transnational, legally‐inclusive, and multidisciplinary councils. The determinations of these councils also have bearing upon Muslim clinicians and patients who encounter the challenges of brain death at the bedside. For those searching for ‘Islamically‐sanctioned’ responses that can inform their practice, both the OIC‐IFA and IOMS verdicts have palpable gaps in their assessments and remain clinically ambiguous. In this paper we analyze these verdicts from the perspective of applied Islamic bioethics and raise several questions that, if answered by future juridical councils, will better meet the needs of clinicians and bioethicists.  相似文献   

3.
Since its origin bioethics has been a specialized, academic discipline, focussing on moral issues, using a vast set of globalized principles and rational techniques to evaluate and guide healthcare practices. With the emergence of a plural society, the loss of faith in experts and authorities and the decline of overarching grand narratives and shared moralities, a new approach to bioethics is needed. This approach implies a shift from an external critique of practices towards embedded ethics and interactive practice improvement, and from a legal defence of rights towards fostering interdependent practices of responsibility. This article describes these transitions within bioethics in relation to the broader societal and cultural dynamics within Western societies, and traces the implications for the methodologies and changing roles of the bioethicist. The bioethicist we foresee is not just a clever expert but also a relationally sensitive person who engages stakeholders in reciprocal dialogues about their practice of responsibility and helps to integrate various sorts of knowledge (embodied, experiential, visual, and cognitive‐scientific). In order to illustrate this new approach, we present a case study. It concerns a project focusing on an innovation in elderly care, based on the participation of various stakeholders, especially older people themselves.  相似文献   

4.
How health care providers are paid affects how medicine is practiced. It is thus important to assess provider payment models not only from the economic perspective but also from the ethical perspective. China recently started to reform the provider payment model in the health care system from fee‐for‐service to case‐based payment. This paper aims to examine this transition from an ethical perspective. We collected empirical studies on the impact of case‐based payment in the Chinese health care system and applied a systematic ethical matrix that integrates clinical ethics and public health ethics to analyze the empirical findings. We identified eleven prominent ethical issues related to case‐based payment. Some ethical problems of case‐based payment in China are comparable to ethical problems of managed care and diagnosis related groups in high‐income countries. However, in this paper we discuss in greater detail four specific ethical issues in the Chinese context: professionalism, the patient‐physician relationship, access to care and patient autonomy. Based on the analysis, we cautiously infer that case‐based payment is currently more ethically acceptable than fee‐for‐service in the context of China, mainly because it seems to lower financial barriers to access care. Nonetheless, it will be difficult to justify the implementation of case‐based payment if no additional measures are taken to monitor and minimize its existing negative ethical implications.  相似文献   

5.
Cultural competence, a clinical skill to recognise patients' cultural and religious beliefs, is an integral element in patient‐centred medical practice. In the area of death and dying, physicians' understanding of patients' and families' values is essential for the delivery of culturally appropriate care. Dementia is a neurodegenerative condition marked by the decline of cognitive functions. When the condition progresses and deteriorates, patients with advanced dementia often have eating and swallowing problems and are at high risk of developing malnutrition. Enteral tube feeding is a conventional means of providing artificial nutrition and hydration to meet nutritional needs, but its benefits to the frail population are limitedly shown in the clinical evidence. Forgoing tube feeding is ethically challenging when patients are mentally incompetent and in the absence of an advance directive. Unlike some developed countries, like the United States of America, death and dying is a sensitive issue or even a taboo in some cultures in developing countries that forgoing enteral tube feeding is clinically and ethically challenging, such as China and Malaysia. This article in three parts 1) discusses the clinical and ethical issues related to forgoing tube feeding among patients with advanced dementia, 2) describes how Hong Kong Chinese, North American, and Malaysian Islamic cultures respond differently in the decision‐making patterns of forgoing tube feeding for patients with advanced dementia, and 3) reiterates the clinical implications of cultural competence in end‐of‐life care.  相似文献   

6.
We report on the synthesis, activity testing, docking, and quantum mechanical scoring of novel imidazo[1,2‐c]pyrimidin‐5(6H)‐one scaffold for cyclin‐dependent kinase 2 (CDK2) inhibition. A series of 26 compounds substituted with aromatic moieties at position 8 has been tested in in vitro enzyme assays and shown to inhibit CDK2. 2D structure‐activity relationships have ascertained that small substituents at position 8 (up to the size of naphtyl or methoxyphenyl) generally lead to single‐digit micromolar IC50 values, whereas bigger substituents (substituted biphenyls) decreased the compounds' activities. The binding modes of the compounds obtained using Glide docking have exhibited up to 2 hinge‐region hydrogen bonds to CDK2 and differed in the orientation of the inhibitor core and the placement of the 8‐substituents. Semiempirical quantum mechanics‐based scoring identified probable favourable binding modes, which will serve for future structure‐based design and synthetic optimization of substituents of the heterocyclic core. In summary, we have identified a novel core for CDK2 inhibition and will explore it further to increase the potencies of the compounds and also monitor selectivities against other protein kinases.  相似文献   

7.
Parasites impose a permanent threat for hosts. As a consequence, immune defenses are important for host fitness. However, the immune response can also produce self‐damage and impair host fitness if not properly regulated. Effectors that up‐ and downregulate the immune response should, therefore, evolve in concert, and be under the action of correlational selection. To address this issue, we assessed the shape of the selection operating on pro‐ and anti‐inflammatory effectors following an inflammatory challenge in laboratory mice. We found that selection acts on the combination of these two traits as individuals that produced large amount of pro‐inflammatory cytokines could achieve relatively high fitness (survival) only if also producing a large amount of anti‐inflammatory effectors. To our knowledge, this is the first study providing evidence for correlational selection on immunity.  相似文献   

8.

Background

The purpose of this study was to determine whether dietary manipulation can reliably induce early‐stage atherosclerosis and clinically relevant changes in vascular function in an established, well‐characterized non‐human primate model.

Methods

We fed 112 baboons a high‐cholesterol, high‐fat challenge diet for two years. We assayed circulating biomarkers of cardiovascular disease (CVD) risk, at 0, 7, and 104 weeks into the challenge; assessed arterial compliance noninvasively at 104 weeks; and measured atherosclerotic lesions in three major arteries at necropsy.

Results

We observed evidence of atherosclerosis in all but one baboon fed the two‐year challenge diet. CVD risk biomarkers, the prevalence, size, and complexity of arterial lesions, plus consequent arterial stiffness, were increased in comparison with dietary control animals.

Conclusions

Feeding baboons a high‐cholesterol, high‐fat diet for two years reliably induces atherosclerosis, with risk factor profiles, arterial lesions, and changes in vascular function also seen in humans.  相似文献   

9.
In this work, a hierarchically porous and ultrathick “breathable” wood‐based cathode for high‐performance Li‐O2 batteries is developed. The 3D carbon matrix obtained from the carbonized and activated wood (denoted as CA‐wood) serves as a superconductive current collector and an ideal porous host for accommodating catalysts. The ruthenium (Ru) nanoparticles are uniformly anchored on the porous wall of the aligned microchannels (denoted as CA‐wood/Ru). The aligned open microchannels inside the carbon matrix contribute to unimpeded oxygen gas diffusion. Moreover, the hierarchical pores on the microchannel walls can be facilely impregnated by electrolyte, forming a continuous supply of electrolyte. As a result, numerous ideal triphase active sites are formed where electrolyte, oxygen, and catalyst accumulate on the porous walls of microchannels. Benefiting from the numerous well‐balanced triple‐phase active sites, the assembled Li‐O2 battery with the CA‐wood/Ru cathode (thickness: ≈700 µm) shows a high specific area capacity of 8.58 mA h cm?2 at 0.1 mA cm?2. Moreover, the areal capacity can be further increased to 56.0 mA h cm?2 by using an ultrathick CA‐wood/Ru cathode with a thickness of ≈3.4 mm. The facile ultrathick wood‐based cathodes can be applied to other cathodes to achieve a super high areal capacity without sacrificing the electrochemical performance.  相似文献   

10.
Energy‐storage technology is moving beyond lithium batteries to sodium as a result of its high abundance and low cost. However, this sensible transition requires the discovery of high‐rate and long‐lifespan anode materials, which remains a significant challenge. Here, the facile synthesis of an amorphous Sn2P2O7/reduced graphene oxide nanocomposite and its sodium storage performance between 0.01 and 3.0 V are reported for the first time. This hybrid electrode delivers a high specific capacity of 480 mA h g?1 at a current density of 50 mA g?1 and superior rate performance of 250 and 165 mA h g?1 at 2 and 10 A g?1, respectively. Strikingly, this anode can sustain 15 000 cycles while retaining over 70% of the initial capacity. Quantitative kinetic analysis reveals that the sodium storage is governed by pseudocapacitance, particularly at high current rates. A full cell with sodium super ionic conductor (NASICON)‐structured Na3V2(PO4)2F3 and Na3V2(PO4)3 as cathodes exhibits a high energy density of over 140 W h kg?1 and a power density of nearly 9000 W kg?1 as well as stability over 1000 cycles. This exceptional performance suggests that the present system is a promising power source for promoting the substantial use of low‐cost energy storage systems.  相似文献   

11.
Science can be seen as a sequential process where each new study augments evidence to the existing knowledge. To have the best prospects to make an impact in this process, a new study should be designed optimally taking into account the previous studies and other prior information. We propose a formal approach for the covariate prioritization, that is the decision about the covariates to be measured in a new study. The decision criteria can be based on conditional power, change of the p‐value, change in lower confidence limit, Kullback–Leibler divergence, Bayes factors, Bayesian false discovery rate or difference between prior and posterior expectation. The criteria can be also used for decisions on the sample size. As an illustration, we consider covariate prioritization based on genome‐wide association studies for C‐reactive protein levels and make suggestions on the genes to be studied further.  相似文献   

12.
13.
There is an escalating interest of using double stranded DNA molecules as a chiral scaffold to construct metal‐biomacromolecule hybrid catalysts for asymmetric synthesis. Several recent studies also evaluated the use of G‐quadruplex DNA‐based catalysts for asymmetric Diels‐Alder and Friedel‐Crafts reactions. However, there is still a lack of understanding of how different oligonucleotides, salts (such as NaCl and KCl), metal ligands and co‐solvents affect the catalytic performance of quadruplex DNA‐based hybrid catalysts. In this study, we aim to systematically evaluate these key factors in asymmetric Michael addition reactions, and to examine the conformational and molecular changes of DNA by circular dichroism (CD) spectroscopy and gel electrophoresis. We achieved up to 95% yield and 50% enantiomeric excess (ee) when the reaction of 2‐acylimidazole 1a and dimethylmalonate was catalyzed by 5′‐G3(TTAG3)3?3′ (G4DNA1) in 20 mM MOPS (pH 6.5) containing 50 mM KCl and 40 µM [Cu(dmbipy)(NO3)2], and G4DNA1 was pre‐sonicated in ice bath for 10 min prior to the reaction. G‐quadruplex‐based hybrid catalysts provide a new tool for asymmetric catalysis, but future mechanistic studies should be sought to further improve the catalytic efficiency. The current work presents a systematic study of asymmetric Michael addition catalyzed by G‐quadruplex catalysts constructed via non‐covalent complexing, and an intriguing finding of the effect of pre‐sonication on catalytic efficiency. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:891–898, 2016  相似文献   

14.
15.
This work shows that, during MD aided by external tiny random forces, 3‐bromo‐4‐hydroxybenzoic acid (LHB), the product of reductive dehalogenation of 3,5‐dibromo‐4‐hydroxybenzoic acid (LBB) by the corrin‐based marine enzyme NpRdhA, is expelled along mainly the wide channel that connects the corrin to the external medium. In accordance, unbiased MD showed that LBB migrates relatively rapidly from the external medium to the inside of the channel, finally getting to the corrin active center of NpRdhA. The LBB pose, with bromide head and carboxylate tail nearly equidistant from the corrin Co ion, does not fit the results of previous automatic docking. Either the experimental structure of the NpRdhA‐LBB complex, or a quantum‐mechanical study of LBB at the corrin active site, are therefore urged.  相似文献   

16.
Aggregative groups entail costs that must be overcome for the evolution of complex social interactions. Understanding the mechanisms that allow aggregations to form and restrict costs of cheating can provide a resolution to the instability of social evolution. Aggregation in Tetrahymena thermophila is associated with costs of reduced growth and benefits of improved survival through “growth factor” exchange. We investigated what mechanisms contribute to stable cooperative aggregation in the face of potential exploitation by less‐cooperative lines using experimental microcosms. We found that kin recognition modulates aggregative behavior to exclude cheaters from social interactions. Long‐distance kin recognition across patches modulates social structure by allowing recruitment of kin in aggregative lines and repulsion in asocial lines. Although previous studies have shown a clear benefit to social aggregation at low population densities, we found that social aggregation has very different effects at higher densities. Lower growth rates are a cost of aggregation, but also present potential benefits when restricted to kin aggregations: slow growth and crowd tolerance allow aggregations to form and permit longer persistence on ephemeral resources. Thus in highly dynamic metapopulations, kin recognition plays an important role in the formation and stability of social groups that increase persistence through cooperative consumptive restraint.  相似文献   

17.
Phylogenetic comparative methods (PCMs) have been used to test evolutionary hypotheses at phenotypic levels. The evolutionary modes commonly included in PCMs are Brownian motion (genetic drift) and the Ornstein–Uhlenbeck process (stabilizing selection), whose likelihood functions are mathematically tractable. More complicated models of evolutionary modes, such as branch‐specific directional selection, have not been used because calculations of likelihood and parameter estimates in the maximum‐likelihood framework are not straightforward. To solve this problem, we introduced a population genetics framework into a PCM, and here, we present a flexible and comprehensive framework for estimating evolutionary parameters through simulation‐based likelihood computations. The method does not require analytic likelihood computations, and evolutionary models can be used as long as simulation is possible. Our approach has many advantages: it incorporates different evolutionary modes for phenotypes into phylogeny, it takes intraspecific variation into account, it evaluates full likelihood instead of using summary statistics, and it can be used to estimate ancestral traits. We present a successful application of the method to the evolution of brain size in primates. Our method can be easily implemented in more computationally effective frameworks such as approximate Bayesian computation (ABC), which will enhance the use of computationally intensive methods in the study of phenotypic evolution.  相似文献   

18.
MicroRNAs (miRNAs) have been confirmed to be closely related to various human complex diseases by many experimental studies. It is necessary and valuable to develop powerful and effective computational models to predict potential associations between miRNAs and diseases. In this work, we presented a prediction model of Graphlet Interaction for MiRNA‐Disease Association prediction (GIMDA) by integrating the disease semantic similarity, miRNA functional similarity, Gaussian interaction profile kernel similarity and the experimentally confirmed miRNA‐disease associations. The related score of a miRNA to a disease was calculated by measuring the graphlet interactions between two miRNAs or two diseases. The novelty of GIMDA lies in that we used graphlet interaction to analyse the complex relationships between two nodes in a graph. The AUCs of GIMDA in global and local leave‐one‐out cross‐validation (LOOCV) turned out to be 0.9006 and 0.8455, respectively. The average result of five‐fold cross‐validation reached to 0.8927 ± 0.0012. In case study for colon neoplasms, kidney neoplasms and prostate neoplasms based on the database of HMDD V2.0, 45, 45, 41 of the top 50 potential miRNAs predicted by GIMDA were validated by dbDEMC and miR2Disease. Additionally, in the case study of new diseases without any known associated miRNAs and the case study of predicting potential miRNA‐disease associations using HMDD V1.0, there were also high percentages of top 50 miRNAs verified by the experimental literatures.  相似文献   

19.
Down syndrome (DS) occurs due to triplication of chromosome 21. Individuals with DS face an elevated risk for development of Alzheimer's disease (AD) due to increased amyloid beta (Aβ) resulting from the over‐expression of the amyloid precursor protein found on chromosome 21. Diagnosis of AD among individuals with DS poses particular challenges resulting in an increased focus on alternative diagnostic methods such as blood‐based biomarkers. The aim of this review was to evaluate the current state of the literature of blood‐based biomarkers found in individuals with DS and particularly among those also diagnosed with AD or in prodromal stages (mild cognitive impairment [MCI]). A systematic review was conducted utilizing a comprehensive search strategy. Twenty‐four references were identified, of those, 22 fulfilled inclusion criteria were selected for further analysis with restriction to only plasma‐based biomarkers. Studies found Aβ to be consistently higher among individuals with DS; however, the link between Aβ peptides (Aβ1‐42 and Aβ1‐40) and AD among DS was inconsistent. Inflammatory‐based proteins were more reliably found to be elevated leading to preliminary work focused on an algorithmic approach with predominantly inflammatory‐based proteins to detect AD and MCI as well as predict risk of incidence among DS. Separate work has also shown remarkable diagnostic accuracy with the use of a single protein (NfL) as compared to combined proteomic profiles. This review serves to outline the current state of the literature and highlights the potential plasma‐based biomarkers for use in detecting AD and MCI among this at‐risk population.  相似文献   

20.
N‐linked glycosylation is known to be a crucial factor for the therapeutic efficacy and safety of monoclonal antibodies (mAbs) and many other glycoproteins. The nontemplate process of glycosylation is influenced by external factors which have to be tightly controlled during the manufacturing process. In order to describe and predict mAb N‐linked glycosylation patterns in a CHO‐S cell fed‐batch process, an existing dynamic mathematical model has been refined and coupled to an unstructured metabolic model. High‐throughput cell culture experiments carried out in miniaturized bioreactors in combination with intracellular measurements of nucleotide sugars were used to tune the parameter configuration of the coupled models as a function of extracellular pH, manganese and galactose addition. The proposed modeling framework is able to predict the time evolution of N‐linked glycosylation patterns during a fed‐batch process as a function of time as well as the manipulated variables. A constant and varying mAb N‐linked glycosylation pattern throughout the culture were chosen to demonstrate the predictive capability of the modeling framework, which is able to quantify the interconnected influence of media components and cell culture conditions. Such a model‐based evaluation of feeding regimes using high‐throughput tools and mathematical models gives rise to a more rational way to control and design cell culture processes with defined glycosylation patterns. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1135–1148, 2016  相似文献   

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