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81.
7,9-Diaryl-1,6,8-trioxaspiro[4.5]dec-3-en-2-ones are a recently described group of spirocyclic butenolides that can be generated rapidly and as a single diastereomer through a cascade process between γ-hydroxybutenolides and aromatic aldehydes. The following outlines our findings that these spirocycles are potently cytotoxic and have a dramatic structure–function profile that provides excellent insight into the structural features required for this potency.  相似文献   
82.
ObjectivesTo describe quitting experiences of cancer patients in a Cancer Center in Jordan; to study patients’ perceptions regarding the process of smoking cessation; and to provide insights about patients in this difficult setting in order to inform oncology practitioners with regards to how improve perceptions and skills related to quitting.MethodsAn Arabic cross-sectional questionnaire was developed to evaluate smoking and quitting behaviors in the context of cancer. The tool used as its framework the Theoretical Domains Framework to capture quitting perceptions of cancer patients who smoke, as well as social, environmental, and system-level factors that influence quitting. Eligible patients who were treated at the Center (both in-patient and out-patient settings) and who were current smokers or who smoked up to the time of cancer diagnosis were eligible. Patients were interviewed between July, 2018 and January 2020 using two versions of the questionnaire: an ‘ex-smokers’ version, and a ‘current smokers’ version.ResultsOnly a third of subjects (104/350) had been smoke-free for at least 30 days. Both smokers and ex-smokers generally felt that quitting was important, but mean importance and confidence scores (out of 10) were significantly lower in current smokers (8.2 versus 9.1, p-value=0.002; 6.4 versus 8.7, p-value=0.000). Roughly 31% of subjects believed smoking harms were exaggerated and that smoking was not an addiction. About 62% of subjects agreed quitting required skills, and 78.5% felt the steps to quit were clear, but across several listed strategies for quitting, use of these was limited (even in ex-smokers). Among current smokers, roughly a third exhibited forms of cessation fatigue.ConclusionJordanian cancer patients who smoke present with limited knowledge about the quitting process. Even when some success is observed, low rates of utilization of specific quitting strategies were observed, highlighting the need for better counseling about quitting.  相似文献   
83.
A series of novel 7-hydroxycoumarin-3-carboxamides was synthesized by the reaction of 7-hydroxy-2-oxo-2H-chromene-3-carboxylic acid with various substituted aromatic amines. The newly synthesized compounds were evaluated for their inhibitory activity against the four physiologically relevant human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms CA I, CA II, CA IX and CA XII. The CA inhibition results show that the newly synthesized 7-hydroxycoumarin-3-carboxamides (4a-n) exhibited selective inhibition of the tumor associated isoforms, CA IX and CA XII over CA I and II isoforms. The inhibition constants ranged from sub micromolar to low micromolar. Amongst all the compounds tested, compound 4m was the most effective inhibitor exhibiting sub micromolar potency against both hCA IX and hCA XII, with a Ki of 0.2 µM. Therefore, it can be anticipated that compound 4m can serve as a lead for development of anticancer therapy by exhibiting a novel mechanism of action. The binding modes of the most potent compounds within hCA IX and XII catalytic clefts were investigated by docking studies.  相似文献   
84.
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Highlights
  • •Brain membrane protein extraction.
  • •Protein prenylation.
  • •Prenyl peptide capture and characterization by LC-MS/MS.
  • •HCD and EThcD peptide fragmentation.
  相似文献   
85.
A. E. King 《Neurophysiology》2006,38(5-6):410-420
The use of amphibian and mammalian in vitro spinal cord preparations, e.g., hemisected cord and transverse slices, has gained in popularity over the years due to the flexibility and ease of use of such preparations compared to classical in vivo approaches. When combined with modern experimental methodologies, such as patch clamping of visualized single cells or post-experimental neuroanatomy, this approach provides a powerful addition to the armamentarium available to study nociceptive processing in the dorsal horn. Some of these novel experimental approaches and the insight into nociception that they have provided are described below. Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 481–491, September–December, 2006.  相似文献   
86.
A micromethod for the quantitative analysis of caffeine present in small quantities (100 μl) of whole blood is described. It is based on the gas chromatographic—mass spectrometric analysis of chloroform extracts of biological samples. The method is relatively simple, rapid, specific and sensitive, as little as 20 ng of caffeine can be measured.  相似文献   
87.
Cancer is the second leading cause of death worldwide. Research on the relationships between trace elements (TE) and the development of cancer or its prevention is a field that is gaining increasing relevance. This review provides an evaluation of the effects of TE (As, Al, B, Cd, Cr, Cu, F, I, Pb, Li, Mn, Hg, Mo, Ni, Se, Si, Sn, V and Zn) intake and supplementation in cancer risk and prevention, as well as their interactions with oncology treatments. Advancements in the knowledge of TE, their dietary interactions and their main food sources can provide patients with choices that will help them to improve their quality of life and therapy outcomes. This approach could open new opportunities for treatments based on the integration of conventional therapies (chemotherapy, radiotherapy, and immunotherapy) and dietary interventions that provide advanced personalized treatments.  相似文献   
88.
Soluble epoxide hydrolase (sEH), a novel therapeutic target for neuropathic pain, is a largely cytosolic enzyme that degrades epoxy-fatty acids (EpFAs), an important class of lipid signaling molecules. Many inhibitors of sEH have been reported, and to date, the 1,3-disubstituted urea has the highest affinity reported for the sEH among the central pharmacophores evaluated. An earlier somewhat water soluble sEH inhibitor taken to the clinic for blood pressure control had mediocre potency (both affinity and kinetics) and a short in vivo half-life. We undertook a study to overcome these difficulties, but the sEH inhibitors carrying a 1,3-disubstituted urea often suffer poor physical properties that hinder their formulation. In this report, we described new strategies to improve the physical properties of sEH inhibitors with a 1,3-disubstituted urea while maintaining their potency and drug-target residence time (a complementary in vitro parameter) against sEH. To our surprise, we identified two structural modifications that substantially improve the potency and physical properties of sEH inhibitors carrying a 1,3-disubstituted urea pharmacophore. Such improvements will greatly facilitate the movement of sEH inhibitors to the clinic.  相似文献   
89.
Gallstone ileus is a rare and potentially serious complication of cholelithiasis. It is defined as a mechanical intestinal obstruction secondary to the presence of a gallstone in the intestinal luz. The most frequent cause is impaction of the calculus in the ileum after passing through a bilioenteric fístula. It has a high morbidity and mortality rate, mainly due to the difficulty and delay in its diagnosis. A retrospective study is presented of 4 cases of gallstone ileus treated between 2013 and 2017 in the Hospital Nuestra Señora del Prado. An analysis was performed on the clinical characteristics, diagnostic tests, and surgical treatment.  相似文献   
90.
1-Phenyl-3-methyl-5-pyrazolone is a reagent, known as PMP, used to derivatize monosaccharides for the study of polysaccharides composition and structure, and for the dosage of carbohydrates in complex media. The same molecule is also known as edaravone, a drug approved for the treatment of stroke and amyotrophic lateral sclerosis. It is also a reactive molecule susceptible to form stable adducts with aromatic aldehydes, such as formylpterin and vanillin. In addition, the molecule serves as a scaffold to design of edaravone analogs and drug conjugates, with various pharmacological properties (antioxidant, anticancer, antiviral). We have analyzed the multiple usages of PMP/edaravone to highlight the reactivity of the molecule and its wide range of applications. This phenyl-pyrazolone compound, considered by many as a biochemical reagent and by other as a clinically useful drug, has not yet revealed the full extent of its capacities and benefits.  相似文献   
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