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61.
62.
Recent social science scholarship has employed the term “pharmaceuticalization” in analyses of the production, circulation and use of drugs. In this paper, we seek to open up further discussion of the scope, limits and potential of this as an analytical device through consideration of the role of law and legal processes in directing pharmaceutical flows. To do so, we synthesize a range of empirical and conceptual work concerned with the relationships between access to medicines and intellectual property law. This paper suggests that alongside documenting the expansion or reduction in demand for particular drugs, analysts of pharmaceuticalization attend to the ways in which socio-legal developments change (or not) the identities of drugs, and the means through which they circulate and come to be used by states and citizens. Such scholarship has the potential to more precisely locate the biopolitical processes that shape international agendas and targets, form markets, and produce health.  相似文献   
63.
Nanosized cellular vesicles “exosome” contains a variety of biological cargo including DNA fragments from cell-of-origin. Despite its biological stability and clinical utility in tumor diagnosis, exosome DNA (ExoDNA) is very little studied as compare with exosome RNA. Cytoplasmic accumulation of damaged DNA from nucleus and mitochondria often leads to its packaging in exosomes by yet unknown pathways. ExoDNA modulates tumor immunity via paracrine interactions and activation of cytosolic DNA sensor pathways, for example, STING, cGAS, and so forth in specific immune cell subsets. In addition to priming tumor immunity, ExoDNA is also emerging as a critical regulator of check-point immunotherapy. As a useful diagnostic biomaterial, ExoDNA contains a variety of clinically relevant tumor-specific mutations representing multiple genes (e.g., EGFR, BRAF, RAS, IDH, and HER2), thus making it a promising “liquid biopsy” material for therapy recommendations. Hence, ExoDNA in addition to tumor immunity modulation, is also emerging as a suitable diagnostic material for personalized therapy in cancer. Here, we review the current status of ExoDNA research and its potential uses in tumor biology.  相似文献   
64.
Prolactin (PRL) is a hormone–cytokine that has been involved in autoimmunity due to its immunoregulatory and lymphoproliferative effects. It is produced by various extrapituitary sites including immune cells, under control of a superdistal promoter that contains a single nucleotide polymorphism − 1149 G/T previously associated with rheumatoid arthritis (RA) susceptibility in European population. The aim of this study was to investigate the association of the extrapituitary PRL − 1149 G/T promoter polymorphism with clinical parameters, clinical activity and disability indices in RA patients from Western Mexico and to analyze the PRL mRNA expression according to the PRL − 1149 G/T promoter polymorphism in total leucocytes from RA patients and controls. We conducted a case–control study that included 258 RA patients and 333 control subjects (CS). The DNA samples were genotyped using the PCR–RFLP method and the PRL mRNA expression was determined by quantitative real time PCR. PRL serum levels and antibodies to cyclic citrullinated peptides (anti-CCP) were measured with ELISA. We found significant differences in the genotype (p = 0.022) and allelic (p = 0.046) distribution of the polymorphism between RA patients and control subjects. According to the dominant genetic model, there is an association between the T allele (GT + TT genotypes) and decreased RA susceptibility in comparison to the G allele carriers (GG genotype) (OR 0.64, 95% CI 0.45–0.92; p = 0.011). The T allele carriers (GT + TT genotypes) had lower titers of anti-CCP antibodies in comparison to the G allele carriers (GG genotype) (median, 66 U/mL vs. 125 U/mL; p = 0.03). Furthermore, the GG homozygotes had higher PRL mRNA expression in comparison to the GT heterozygotes, and this latter with respect to the TT homozygotes, in both groups (RA: 1 > 0.72 > 0.19; CS: 1 > 0.54 > 0.28). However, PRL serum levels were similar in both groups. Our results suggest that the PRL − 1149 T allele is a genetic marker for decreased RA susceptibility and is associated with lower titers of anti-CCP antibodies in Mexican population. We also suggest influence of genotype upon PRL mRNA expression.  相似文献   
65.
New antibiotics with novel mechanisms of action are urgently needed to overcome the growing bacterial resistance problem faced by clinicians today. PC190723 and related compounds represent a promising new class of antibacterial compounds that target the essential bacterial cell division protein FtsZ. While this family of compounds exhibits potent antistaphylococcal activity, they have poor activity against enterococci and streptococci. The studies described herein are aimed at investigating the molecular basis of the enterococcal and streptococcal resistance to this family of compounds. We show that the poor activity of the compounds against enterococci and streptococci correlates with a correspondingly weak impact of the compounds on the self-polymerization of the FtsZ proteins from those bacteria. In addition, computational and mutational studies identify two key FtsZ residues (E34 and R308) as being important determinants of enterococcal and streptococcal resistance to the PC190723-type class of compounds.  相似文献   
66.
Platinum-based anti-cancer agents have been used for many years to treat many different types of cancer. However, the efficacy of these drugs is limited by serious side effects. One of the strategies to reduce the side effects is encapsulation of the drug in a lipid formulation. Recently, we discovered a novel method for the efficient encapsulation of cisplatin in a lipid formulation. The method is unique in that it does not generate conventional liposomes but nanocapsules: small aggregates of solid cisplatin covered by a lipid bilayer. Also carboplatin, a cisplatin-derived anti-cancer drug with different chemical properties, can be efficiently encapsulated by a similar method. The encapsulation in nanocapsules dramatically improves the in vitro cytotoxicity of the platinum drugs. Our results hold the promise that the nanocapsule technology could prove successful in the efficient encapsulation of many other (platinum-based) drugs, and thereby improve their therapeutic index and profile in vivo.  相似文献   
67.
Abstract

Exploiting the burgeoning fields of genomics, proteomics and metabolomics improves understanding of human physiology and, critically, the mutations that signal disease susceptibility. Through these emerging fields, rational design approaches to diagnosis, drug development and ultimately personalized medicine are possible. Personalized medicine and point-of-care testing techniques must fulfill a host of constraints for real-world applicability. Point-of-care devices (POCDs) must ultimately provide a cost-effective alternative to expensive and time-consuming laboratory tests in order to assist health care personnel with disease diagnosis and treatment decisions. Sensor technologies are also expanding beyond the more traditional classes of biomarkers – nucleic acids and proteins – to metabolites and direct detection of pathogens, ultimately increasing the palette of available techniques for the use of personalized medicine. The technologies needed to perform such diagnostics have also been rapidly evolving, with each generation being increasingly sensitive and selective while being more resource conscious. Ultimately, the final hurdle for all such technologies is to be able to drive consumer adoption and achieve a meaningful medical outcome for the patient.  相似文献   
68.
The importance of Ca2+ signaling in astrocytes is undisputed but a potential role of Ca2+ influx via L-channels in the brain in vivo is disputed, although expression of these channels in cultured astrocytes is recognized. This study shows that an increase in free cytosolic Ca2+ concentration ([Ca2+]i) in astrocytes in primary cultures in response to an increased extracellular K+ concentration (45 mM) is inhibited not only by nifedipine (confirming previous observations) but also to a very large extent by ryanodine, inhibiting ryanodine receptor-mediated release of Ca2+, known to occur in response to an elevation in [Ca2+]i. This means that the actual influx of Ca2+ is modest, which may contribute to the difficulty in demonstrating L-channel-mediated Ca2+ currents in astrocytes in intact brain tissue. Chronic treatment with any of the 3 conventional anti-bipolar drugs lithium, carbamazepine or valproic acid similarly causes a pronounced inhibition of K+-mediated increase in [Ca2+]i. This is shown to be due to an inhibition of capacitative Ca2+ influx, reflected by decreased mRNA and protein expression of the ‘transient receptor potential channel’ (TRPC1), a constituent of store-operated channels (SOCEs). Literature data are cited (i) showing that depolarization-mediated Ca2+ influx in response to an elevated extracellular K+ concentration is important for generation of Ca2+ oscillations and for the stimulatory effect of elevated K+ concentrations in intact, non-cultured brain tissue, and (ii) that Ca2+ channel activity is dependent upon availability of metabolic substrates, including glycogen. Finally, expression of mRNA for Cav1.3 is demonstrated in freshly separated astrocytes from normal brain.  相似文献   
69.
The anti-amyloid properties shared by several quinones inspired the design of a new series of hybrids derived from the multi-target drug candidate memoquin (1). The hybrids consist of a central benzoquinone core and a fragment taken from non-steroidal anti-inflammatory drugs, connected through polyamine linkers. The new hybrids retain the potent anti-aggregating activity of the parent 1, while exhibiting micromolar AChE inhibitory activities. Remarkably, 2, 4, (R)-6 and (S)-6 were Aβ aggregation inhibitors even more potent than 1. The balanced amyloid/cholinesterase inhibitory profile is an added value that makes the present series of compounds promising leads against Alzheimer’s disease.  相似文献   
70.
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