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911.
912.
Daniel A. Real María V. Martinez Agustín Frattini Marina Soazo Alicia G. Luque Marisa S. Biasoli Claudio J. Salomon Alejandro C. Olivieri Darío Leonardi 《AAPS PharmSciTech》2013,14(1):64-73
The objective of the present paper was the development and the full characterization of antifungal films. Econazole nitrate (ECN) was loaded in a polymeric matrix formed by chitosan (CH) and carbopol 971NF (CB). Polyethylene glycol 400 and sorbitol were used as plasticizing agents. The mechanical properties of films were poorer when the drug was loaded, probably because crystals of ENC produces network outages and therefore reduces the polymeric interactions between the polymers. Polymers–ECN and CH–CB interactions were analyzed by Fourier-transform infrared spectroscopy (FTIR), thermal gravimetry analysis, and differential thermal analysis (DTA-TGA). ECN did not show structure alterations when loaded into the films. In scanning electron microphotographs and atomic force microscopy analysis, films prepared with CB showed an evident wrinkle pattern probably due to the strong interactions between the polymers, which were observed by FTIR and DTA-TGA. The in vitro activity of the formulations against Candida krusei and Candida parapsilosis was twice as greater as the commercial cream, probably as a result of the antifungal combination of the drug with the CH activity. All these results suggest that these polymeric films containing ECN are potential candidates in view of alternatives dosages forms for the treatment of the yeast assayed. 相似文献
913.
Valeria V. Costantino Sabrina F. Mansilla Juliana Speroni Celina Amaya Darío Cuello-Carrión Daniel R. Ciocca Horacio A. Priestap Manuel A. Barbieri Vanesa Gottifredi Luis A. Lopez 《PloS one》2013,8(1)
Sesquiterpene lactones (SLs) are plant-derived compounds that display anti-cancer effects. Some SLs derivatives have a marked killing effect on cancer cells and have therefore reached clinical trials. Little is known regarding the mechanism of action of SLs. We studied the responses of human cancer cells exposed to various concentrations of dehydroleucodine (DhL), a SL of the guaianolide group isolated and purified from Artemisia douglasiana (Besser), a medicinal herb that is commonly used in Argentina. We demonstrate for the first time that treatment of cancer cells with DhL, promotes the accumulation of DNA damage markers such as phosphorylation of ATM and focal organization of γH2AX and 53BP1. This accumulation triggers cell senescence or apoptosis depending on the concentration of the DhL delivered to cells. Transient DhL treatment also induces marked accumulation of senescent cells. Our findings help elucidate the mechanism whereby DhL triggers cell cycle arrest and cell death and provide a basis for further exploration of the effects of DhL in in vivo cancer treatment models. 相似文献
914.
915.
Ajay Raj Ajay Pratap Singh Ranjit Kumar Nath Neeraj Pandit Puneet Aggarwal Ashok Kumar Thakur Rajeev Bharadwaj Vinod Kumar 《Indian pacing and electrophysiology journal》2021,21(3):162-168
Background and objectivesQuadripolar left ventricular (LV) leads in cardiac resynchronization therapy (CRT) offer multi-vector pacing with different pacing configurations and hence enabling LV pacing at most suitable site with better lead stability. We aim to compare the outcomes between quadripolar and bipolar LV lead in patients receiving CRT.MethodsIn this prospective, non-randomized, single-center observational study, we enrolled 93 patients receiving CRT with bipolar (BiP) (n = 31) and quadripolar (Quad) (n = 62) LV lead between August 2016 to August 2019. Patients were followed for six months, and outcomes were compared with respect to CRT response (defined as ≥5% absolute increase in left ventricle ejection fraction), electrocardiographic, echocardiographic parameters, NYHA functional class improvement, and incidence of LV lead-related complication.ResultsAt the end of six months follow up, CRT with quadripolar lead was associated with better response rate as compared to bipolar pacing (85.48% vs 64.51%; p = 0.03), lesser heart failure (HF) hospitalization events (1.5 vs 2; p = 0.04) and better improvement in HF symptoms (patients with ≥1 NYHA improvement 87.09% vs 67.74%; p = 0.04). There were fewer deaths per 100 patient-year (6.45 vs 9.37; p = 0.04) and more narrowing of QRS duration (Δ12.56 ± 3.11 ms vs Δ7.29 ± 1.87 ms; p = 0.04) with quadripolar lead use. Lead related complications were significantly more with the use of bipolar lead (74.19% vs 41.94%; p = 0.02).ConclusionsOur prospective, non-randomized, single-center observational study reveals that patients receiving CRT with quadripolar leads have a better response to therapy, lesser heart failure hospitalizations, lower all-cause mortality, and fewer lead-related complications, proving its superiority over the bipolar lead. 相似文献
916.
Abir Mondal Soumyadeep Mukherjee Waseem Dar Shailja Singh Soumya Pati 《生物化学与生物物理学报:疾病的分子基础》2021,1867(10):166185
Autism Spectrum Disorder (ASD) is a common group of neurodevelopmental disorders which causes significant alterations in social and communication skills along with repetitive behavior and limited interests. The physiological understanding of ASD is ambiguous. Several reports suggested that environmental, genetic and epigenetic changes, neuroinflammation, mitochondrial dysfunction and metabolic alterations orchestrate the pathological outcomes of ASD. A recent report from Saudi Arabia found a mutation in X-chromosomal housekeeping glucose 6-phosphate dehydrogenase (G6PD) gene in two male ASD patients. Although, the involvement of G6PD-deficiency in the pathogenesis of ASD is poorly understood. Several reports suggested that G6PD deficiency impedes cellular detoxification of reactive oxygen species (ROS), which may result in neuronal damage and neuroinflammation. A deficiency of G6PD in newborn children may play a fundamental role in the pathogenesis of ASD. In this review, we will discuss the implications of G6PD deficiency in pathogenesis, male biasness and theranostics in ASD patients. 相似文献
917.
Cavanaugh NA Beard WA Batra VK Perera L Pedersen LG Wilson SH 《The Journal of biological chemistry》2011,286(36):31650-31660
DNA polymerases can misinsert ribonucleotides that lead to genomic instability. DNA polymerase β discourages ribonucleotide insertion with the backbone carbonyl of Tyr-271; alanine substitution of Tyr-271, but not Phe-272, resulted in a >10-fold loss in discrimination. The Y271A mutant also inserted ribonucleotides more efficiently than wild type on a variety of ribonucleoside (rNMP)-containing DNA substrates. Substituting Mn2+ for Mg2+ decreased sugar discrimination for both wild-type and mutant enzymes primarily by increasing the affinity for rCTP. This facilitated crystallization of ternary substrate complexes of both the wild-type and Y271A mutant enzymes. Crystallographic structures of Y271A- and wild type-substrate complexes indicated that rCTP is well accommodated in the active site but that O2′ of rCTP and the carbonyl oxygen of Tyr-271 or Ala-271 are unusually close (∼2.5 and 2.6 Å, respectively). Structure-based modeling indicates that the local energetic cost of positioning these closely spaced oxygens is ∼2.2 kcal/mol for the wild-type enzyme. Because the side chain of Tyr-271 also hydrogen bonds with the primer terminus, loss of this interaction affects its catalytic positioning. Our results support a model where DNA polymerase β utilizes two strategies, steric and geometric, with a single protein residue to deter ribonucleotide insertion. 相似文献
918.
This study investigates how various social, demographic and economic factors affect spousal agreement on preferred waiting time to next birth. Data for matched cohabiting couples from ten Demographic and Health Surveys in sub-Saharan Africa (Benin, Burkina Faso, Ghana, Guinea, Mali, Ethiopia, Kenya, Mozambique, Zambia and Zimbabwe), conducted between 2003 and 2006, were analysed to compare reported waiting time to next birth by the husband and the wife. Couples where the reported waiting time to next birth was the same for both partners (difference is 0 months) were defined as having agreement on waiting time to next birth. In sub-Saharan Africa, spousal agreement on waiting time to next birth was found to be associated with wanting the next child sooner. When the spouses disagree on waiting time to next birth, the wives want to wait longer than their husbands in most cases. Additionally, the study found that demographic factors are the primary determinants of spousal agreement on waiting time to next birth, not socioeconomic factors. The strongest predictors of spousal agreement on waiting time to next birth were number of living children, difference between the number of ideal and living children and wife's age. Couples with fewer children, a younger wife and those with a difference of five or more children between ideal and living number of children were more likely to agree on waiting time to next birth. Effects of socioeconomic factors, such as education and wealth status, on spousal agreement on waiting time to next birth were generally weak and inconsistent. The findings highlight some of the challenges in developing programmes to promote spousal communication and birth spacing and underscore the need for programmes to be gender-sensitive. 相似文献
919.
Fernández D Larrucea S Nowakowski A Pericacho M Parrilla R Ayuso MS 《Biochimica et biophysica acta》2011,1813(8):1504-1510
Podocalyxin (PODXL) is a type I membrane mucoprotein abundantly presented in the epithelial cells (podocytes) of kidney glomeruli where it plays an important role in maintaining the plasma filtration. PODXL is also expressed in other types of cells but its function is ignored. A recombinant soluble fragment of the PODXL ectodomain modifies the signaling of the membrane bound PODXL. Based on this antecedent, we aimed at investigating whether PODXL could be cleaved and released into the extracellular space as a soluble peptide. In this study, we used a fusion protein of human PODXL and green fluorescent protein expressed in CHO cells (CHO-PODXL-GFP) and a human tumor cell (Tera-1) inherently expressing PODXL. PODXL was detected by wide-field microscopy in the Golgi, the plasma membrane and in a vesicular form preferentially located at the leading edges of the cell and also progressing along the filopodium. We detected PODXL in the insoluble and soluble fractions of the extracellular medium of CHO-PODXL-GFP cells. Stimulation of protein kinase C (PKC) by Phorbol-12-myristate-13-acetate (PMA) enhanced the release of PODXL to the extracellular space whereas this effect was prevented either by inhibitors of PKC or specific inhibitors of matrix metalloproteinases. It is concluded that intact PODXL is released to the extracellular space as a cargo of microvesicles and also as a soluble cleaved fragment of ectodomain. 相似文献
920.
Mazzola EP Parkinson A Kennelly EJ Coxon B Einbond LS Freedberg DI 《Carbohydrate research》2011,(6):759-768
The structures of three complex saponins from the fruit pods of Blighia sapida have been elucidated and their 1H and 13C NMR spectra assigned employing a variety of one- and two-dimensional NMR techniques without degradative chemistry. The saponins have either four or six monosaccharide units linked to a triterpene aglycone. High-resolution, proton-coupled-HSQC spectra were important for determining both the identities of the intact monosaccharide units and coupling constants in strongly coupled proton spin systems. These NMR experiments will prove crucial as the complexity of saponin structures reaches the limit that can be determined solely by NMR. 相似文献