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This review presents the first detailed presentation of the parallelism between the Tuskegee Syphilis Study and the Captain America graphic novel ‘TRUTH: Red, White and Black’, published as a graphic novel by Marvel Comics in 2004 as a paperback, and then in 2009 as a hardcover. First written, published and distributed monthly in 2003 as pre-sequel seven comic book series to tell the story of the origins of the WWII superhero Captain America. In 2003, Marvel Comics chose to tell a ‘very dark story’ to explain the origins of Captain America, a half century after the initial introduction of Captain America as a WWII action hero in 1940. By detailing—for the first time—nine parallel aspects between these two storylines, this review demonstrates how Marvel Comics brought the tragic Tuskegee Syphilis Study story into the popular press, thus reaching an audience far beyond traditional bioethics academicians. This review is intended to stimulate and guide classroom discussions on the ethical issues at the core of the infamous Tuskegee Syphilis Study allowing bioethical issues to be made more accessible to the general public, via school curriculums, by the use of graphic novels.  相似文献   
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Introduction: Although used as an anesthetic drug for decades, ketamine appears to have garnered renewed interest due to its potential therapeutic uses in pain therapy, neurology, and psychiatry. Ketamine undergoes extensive oxidative metabolism by cytochrome P450 (CYP) enzymes. Considerable efforts have been expended to elucidate the ketamine-induced regulation of CYP gene expression. The safety profile of chronic ketamine administration is still unclear. Understanding how ketamine regulates CYP gene expression is clinically meaningful.

Areas covered: In this article, the authors provide a brief review of clinical applications of ketamine and its metabolism by CYP enzymes. We discuss the effects of ketamine on the regulation of CYP gene expression, exploring aspects of cytoskeletal remodeling, mitochondrial functions, and calcium homeostasis.

Expert opinion: Ketamine may inhibit CYP gene expression through inhibiting calcium signaling, decreasing ATP levels, producing excessive reactive oxygen species, and subsequently perturbing cytoskeletal dynamics. Further research is still needed to avoid possible ketamine–drug interactions during long-term use in the clinic.  相似文献   

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Porphyromonas gingivalis has been shown to attack host defense systems through proteolytic cleavage of a wide variety of members of the systems. In this study, we examined the ability of P. gingivalis culture supernatant to alter the expression of human T cell surface proteins. As judged by flow cytometric analysis, detection of CD4 expression was completely eliminated by the supernatant, but CD8 was less sensitive. When the culture supernatant was added with reducing agents, proteolytic activity was enhanced, resulting in the cleavage of CD8. Mitogenic response of T cells to phytohemagglutinin or concanavalin A was decreased by the treatment of the cells with the culture supernatant of P. gingivalis. The three forms of gingipains (high molecular mass arginine-specific gingipain, arginine-specific gingipain 2 and lysine-specific gingipain) purified from the culture supernatant of P. gingivalis actively cleaved CD4 and CD8 on human T cells, indicating that proteolytic activity of the culture supernatant was due to gingipains. These results suggest that cysteine proteinases like gingipains released from P. gingivalis cleave T cell surface proteins and impede T cell function.  相似文献   
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目的针对临床型漂白剂在使用中直接接触牙颈部暴露的牙本质和通过牙釉质渗透到牙本质的特点,观察30%双氧水对牙本质中的Ca/P的影响.方法实验组7颗离体牙浸泡在30%双氧水24小时后,对照组5颗离体牙浸泡在生理盐水中24小时后,两组使用OCPC法对浸泡液中的Ca离子含量进行测定,同时运用Fiske-Subbarow法对浸泡液中的磷酸根含量进行测定.然后两组进行统计学比较分析.结果实验组30%双氧水浸泡液中Ca/P含量明显高于对照组(P<0.01).说明在30%双氧水浸泡过程中发生了明显脱矿现象.结论 30%双氧水对牙本质有脱矿作用,建议在使用临床型漂白治疗后应加以再矿化和防龋措施.  相似文献   
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P- gingivalis is considered to be a major pathogen of adult periodontitis. Among its cadre of putative virulence factors are hemagglutinins (adhesins) and proteases. We here report the cloning, sequencing and characterization of two genes, designated kgp(381) and hagD. Kgp(381), an open reading frame (ORF) of 1095 bp encoding a 40.1 kda protein, has high homology to the proteolytic domain of cysteine protease/hemagglutinin genes. HagD, an ORF of 4077 bp encoding a 147.1 kda protein, contains one HArep sequence which establishes it as an additional member of the HArep multigene family. Although similar in sequence to kgp and prtP which were identified from strains HG66 and W12, respectively, the kgp(381)-hagD genes have several characteristics which distinguish them from kgp and prtP. Foremost among these is a single base difference which produces a termination codon and an immediate frame shift resulting in two ORFs in strain 381 as compared to one ORF in strains HG66 and W12. In addition, a 172 amino acid sequence near the C-terminal end of hagD has very low identity (20.5–27.8%) to the corresponding region of kgp and prtP. These demonstrate that the homologue of kgp and prtP in strain 381 occurs as two separate genes which may genetically separate the adhesive and enzymatic domains of Kgp and PrtP proteins. Reverse polymerase chain reaction (PCR) analysis indicates that hagD expression is regulated by hemin concentration.  相似文献   
18.
口腔鳞癌P-gp、GST-π表达与化疗药物耐受性   总被引:1,自引:1,他引:1  
目的 探讨P-糖蛋白(P-glycoprotein,P-gp)和谷胱甘肽S转移酶π(glutathione transferase-π,GST-π)表达与化疗药物耐受性的关系。方法 采用免疫组化过氧化物酶标记法检测口腔颌面部鳞癌和正常口腔粘膜组织样本中P-gp和GST-π的表达,结合MTT药敏检测结果分析。结果 P-gp和GST-π在恶性肿瘤中阳性表达率分别为57.1%和53.6%,在正常组织中未见表达;P-gp的表达与化疗药物总体耐受性有关;GST-π的表达与患者顺铂耐受性有关。结论 P-gp和GST-π的阳性表达提示患者有化疗药物耐受倾向。P-pg和GST-π检测对判断口腔颌面部恶性肿瘤化疗耐药性有指导意义。  相似文献   
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A number of experimental data on biomimetic deposition CaP (BDCaP) coating implants have reported promising outcomes by histological evaluation. But little is investigated on the role of the BDCaP coating and osseointegration mechanism by interface shear strength. To make a direct biomechanical comparison between the BDCaP coating implants and the uncoated rough titanium implants (control), a well-established animal model for implants removal torque testing was employed in rabbits, using a self-matching experimental design. All implants had an identical cylindrical screw shape without any macroscopic retentive structure. After 2, 4, 6, 8 and 12 weeks of bone healing, removal torque testing was performed to evaluate the interfacial shear strength of each implant type. The torqued implants were sputter-coated with gold for morphology observation and observed with a field-emission electron microscopy. Results showed that the interfacial shear strength of the BDCaP coating implants was similar to that of the uncoated rough implants at 2 and 4 weeks of healing. The mean removal torque values of the BDCaP coating implants were lower than those of control implants (P < 0.05) after 6 weeks of healing. The removal torque values for both types of implants revealed similar mean values after 8 and 12 weeks of healing; there were no significant difference between the two types of implants (P > 0.05). It can be concluded that the BDCaP coating implants had no beneficial effect on the interfacial shear strength at early bone healing stage.  相似文献   
20.
ObjectivesTemporomandibular joint osteoarthritis (TMJ-OA) causes degenerative changes in TMJ tissues. The inter-tissue crosstalk that exacerbates illness and organic changes in bone secondary to TMJ-OA potentially affects the muscles; therefore, patients with a muscular disease might also suffer from bone disease. However, knowledge gaps exist concerning muscle pathology at the onset of TMJ-OA. In this study, we documented the pathogeneses of the bone and muscle at the onset of TMJ-OA using a mouse model.MethodsWe performed a partial resection of the TMJ disk to establish a mouse model of TMJ-OA. After the onset of TMJ-OA, we performed various measurements at 8, 12, and 16 weeks post-surgery in the defined groups.ResultsThe volume of the mandibular head in the TMJ-OA group was significantly greater than that in the control group. The temporal muscles in the TMJ-OA group were significantly deformed compared with those in the control group; however, between-group comparisons did not reveal significant differences in the mandibular head or temporal muscles after surgery. Therefore, we hypothesized that the degree of mandibular head hypertrophy would alter the temporal muscles. A subsequent analysis of the correlation between the bone and muscle confirmed that the deformity of the temporal muscle increased with increasing hypertrophy of the mandibular head. Temporal and masseter muscle contact was observed in 25% of surgical groups.ConclusionsThis study demonstrates that TMJ-OA progressed when organic changes occurred in bones and muscles, supporting the symbiotic relationship between bones and muscles.  相似文献   
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