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51.
Aize Pellon Andoni Ramirez-Garcia Idoia Buldain Aitziber Antoran Leire Martin–Souto Aitor Rementeria Fernando L. Hernando 《International journal of antimicrobial agents》2018,51(1):10-15
The number of fungal isolates resistant to antifungal drugs has increased dramatically over the last few years and has become an important concern for clinicians. Among these isolates, fungi showing multidrug resistance are particularly worrying because of the difficulties associated with their treatment. These factors hamper the successful recovery of patients and drastically raise mortality rates. Antifungal resistance is multifactorial and several mechanisms in different fungi have been described. There is a need to study these mechanisms in depth; however, the study of antifungal drug resistance separately for each individual species makes progress in the field very slow and tedious. The selection of a multiresistant microorganism as a model for understanding resistance mechanisms and extrapolating the results to other species could help in the search for a solution. In this mini-review, we describe the pathobiology of Lomentospora (Scedosporium) prolificans, paying special attention to its intrinsic resistance to all currently available antifungal agents. The characteristics of L. prolificans offer several advantages: the possibility of using a single microorganism for the study of resistance to different drugs, even cases of double and triple resistance; it is biologically safe for society in general as no new genetically–modified strains are needed for the experiments; it is homologous with other fungal species, and there is repetitiveness between different strains. In conclusion, we propose L. prolificans as a candidate for consideration as a fungal model for the study of resistance mechanisms against antifungal agents. 相似文献
52.
Dinesh K. Mishra Ruchita Shandilya Pradyumna K. Mishra 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(7):2023-2050
Over the recent couple of decades, pharmaceutical field has embarked most phenomenal noteworthy achievements in the field of medications as well as drug delivery. The rise of Nanotechnology in this field has reformed the existing drug delivery for targeting, diagnostic, remedial applications and patient monitoring. The convincing usage of nanotechnology in the conveyance of medications that prompts an extension of novel lipid-based nanocarriers and non-liposomal systems has been discussed. Present review deals with the late advances and updates in lipidic nanocarriers, their formulation strategies, challenging aspects, stability profile, clinical applications alongside commercially available products and products under clinical trials. This exploration may give a complete idea viewing the lipid based nanocarriers as a promising choice for the formulation of pharmaceutical products, the challenges looked by the translational process of lipid-based nanocarriers and the combating methodologies to guarantee the headway of these nanocarriers from bench to bedside. 相似文献
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55.
Fengling Wang Xi Ye Yifan Wu Huihui Wang Chengming Sheng Daiyin Peng Weidong Chen 《Journal of pharmaceutical sciences》2019,108(1):641-651
Repeated injection of PEGylated liposomes can cause the disappearance of long circulating property because of the induction of anti-PEG IgM antibody referred to as “accelerated blood clearance (ABC) phenomenon.” Although ABC phenomenon typically occurs when entrapped drugs are chemotherapeutic agent with low cytotoxic, there is little evidence of accelerated blood clearance of PEGylated herbal-derived compound on repeated injection. Herein, we investigated the blood concentration of PEGylated liposomal gambogenic acid (PEG-GEA-L), a model PEGylated liposomal herbal extract, on its repeated injection to rats. We found time interval between injections had considerable impact on the magnitude of ABC phenomenon induced by PEG-GEA-L. When time interval was prolonged from 3 days to 7 days, ABC phenomenon could be attenuated. Furthermore, its magnitude was enhanced accompanied by a marked rise in the accumulation of PEG-GEA-L in the liver and spleen in a first-dose–dependent manner. Consistently, the level of anti-PEG IgM significantly increased with the first dose of PEG-GEA-L and decreased with the extended time interval between injections, which implies anti-PEG IgM is a major contributor to the ABC phenomenon. Notably, the increased expression of liver anti-PEG IgM was accompanied by an increased expression of efflux transporters in the induction process of the ABC phenomenon. 相似文献
56.
Jiaqi Yu Hao Chen Linxia Jiang Jianhong Wang Jundong Dai Jie Wang 《Journal of pharmaceutical sciences》2019,108(5):1788-1799
Transmembrane protein P-gp's overexpression at the drug-resistant cell membrane is the most important characteristic of multidrug resistance (MDR). Quercetin (QUE) can effectively suppress the function of P-gp to reverse MDR. This study uses QUE as the P-gp inhibitor andfilm-ultrasound technique with ammonium sulfate transmembrane gradient method to prepare long-circulating liposomes simultaneously encapsulating QUE and Adriamycin (doxorubicin) (AMD/DOX). The optimal conditions for the preparation of AMD_QUE_long-circulating liposomes (SLs) are as follows: hydrogenated soybean phospholipids (HSPC):cholesterol:DSPE-PEG 2000 = 73.07:24.36:2.57 mol/mol, QUE:HSPC = 1:20 mol/mol, AMD:HSPC = 1:7.9 w/w (NH4)2SO4 0.15 mol/L, drug loaded (AMD) at 55°C for 25 min). The average encapsulation efficiency of AMD and QUE was 97.49% and 95.50%, respectively. The average particle size is 85 nm (n = 3), and the average zeta potential is ?14.9 mV. First, the pharmacokinetic study proved that codelivery liposomes enveloping QUE and AMD (AMD_QUE_SL) can obviously increase the blood concentration of AMD (Cmax: 140.50 ± 32.37 μg/mL) and extend the half-life period of AMD in plasma (t1/2:14.02 ± 1.54 h). Second, AMD_QUE_SL can obviously enhance the cell toxicity to AMD-resistant cell strains (HL-6/ADR and MCF-7/ADR), and the reverse effects on the resistance of HL-6/ADR and MCF-7/ADR is increased to 4.81-fold and 3.21-fold, respectively. Third, according to the in vivo pharmacodynamic study, the relative tumor volume and relative tumor growth of the AMD_QUE_SL group were the lowest. The inhibition rate of tumor growth of this group was the highest. It can be concluded that AMD_QUE_SL can effectively reverse MDR, lower cardiac toxicity of AMD in clinical treatment, and improve the clinical treatment effect of AMD. 相似文献
57.
Miey Park Han-Sung KimKyu Sung Shin Hyun Soo KimJi Young Park Wonkeun SongHyoun Chan Cho Kyu Man LeeJae-Seok Kim 《Vaccine》2014
Here, we examined the distribution of pneumococcal serotypes and the antibiotic susceptibility of Streptococcus pneumoniae in clinical blood isolates. The serotypes of 91 S. pneumoniae blood isolates, collected from January 2003 to March 2014, were identified by multiplex PCR and sequencing. The most common serotypes were 19F, 19A, 3, 4, and 14, accounting for 53.8% of the total. The serotype coverage rates of pneumococcal conjugated vaccine (PCV) 7, PCV10, and PCV13 were different during three test periods: 38.7%, 70.9%, and 93.5% in period I (2003–2005), 46.8%, 50.0%, and 75.0% in period II (2006–2008), and 28.5%, 32.1%, and 64.2% in period III (2009–2014), respectively. By contrast, the number of non-PCV13 serotypes increased from 6.4% in period I to 25% and 35.7% in periods II and III, respectively. The susceptibility of non-PCV13 serotypes to antimicrobial agents (penicillin, erythromycin, cefotaxime, and meropenem) was higher than that of PCV serotypes. In particular, non-PCV13 serotypes showed 100% and 95% susceptibility to penicillin and cefotaxime, respectively. Serotypes 19A and 19F showed high prevalence (79.1%) among 24 multi-drug resistant (MDR) isolates. Notably, all serotype 19A isolates were MDR. From January 2003 to March 2014, the proportion of non-PCV13 serotype pneumococci in blood isolates increased whereas the coverage rate of PCV13 decreased. Effective pneumococcal vaccines are required to protect against MDR serotype 19A isolates and the increasing number of non-PCV13 serotypes. 相似文献
58.
X.M. Wang S.J. Gao X.F. Guo W.J. Sun Z.Q. Yan W.X. Wang Y.Q. Xu D. Lu 《Brazilian journal of medical and biological research》2014,47(4):273-278
Overexpression of cytokine-induced apoptosis inhibitor 1 (CIAPIN1) contributes to
multidrug resistance (MDR) in breast cancer. This study aimed to evaluate the
potential of CIAPIN1 gene silencing by RNA interference (RNAi) as a
treatment for drug-resistant breast cancer and to investigate the effect of
CIAPIN1 on the drug resistance of breast cancer in
vivo. We used lentivirus-vector-based RNAi to knock down
CIAPIN1 in nude mice bearing MDR breast cancer tumors and found
that lentivirus-vector-mediated silencing of CIAPIN1 could
efficiently and significantly inhibit tumor growth when combined with chemotherapy
in vivo. Furthermore, Western blot analysis showed that both
CIAPIN1 and P-glycoprotein expression were efficiently downregulated, and P53 was
upregulated, after RNAi. Therefore, we concluded that lentivirus-vector-mediated RNAi
targeting of CIAPIN1 is a potential approach to reverse MDR of
breast cancer. In addition, CIAPIN1 may participate in MDR of breast
cancer by regulating P-glycoprotein and P53 expression. 相似文献
59.
【目的】探讨膀胱癌中多药耐药基因(MDR1)与p53基因表达的临床意义。【方法】采用免疫组化(SABC)法对32例膀胱移行细胞癌中MDR1表达产物P—GP与p53基因产物p53蛋白进行了检测。【结果】32例膀胱移行细胞癌中P—GP、p53阳性率分别为41.0%和47.0%,且随膀胱癌的病理分级和临床分期而增高。T2~T4期同Tis~T1期相比,MDR1及p53的表达均差异有显著性。【结论】临床检测MDR1及p53可对膀胱癌患者提供更多的预后信息。 相似文献
60.
Zih-Ying Li Sheng-Yi Chen Ming-Hong Weng Gow-Chin Yen 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2021,29(2):262
Gemcitabine (GEM) is a first-line drug for pancreatic cancer therapy, but GEM resistance is easily developed in patients. Growing evidence suggests that cancer chemoprevention and suppression are highly associated with dietary phytochemical and microbiota composition. Ursolic acid (UA) has anti-inflammatory and anticancer effects; however, its role in improving cancer drug resistance in vivo remains unclear. In this study, the aim was to explore the role of UA in managing drug resistance-associated molecular mechanisms and the influence of gut microbiota. The in vitro results showed that receptor for advanced glycation end products (RAGE), nuclear factor kappa B p65 (NF-κB/p65), and multidrug resistance protein 1 (MDR1) protein levels were significantly increased in GEM-resistant pancreatic cancer cells (named MIA PaCa-2 GEMR) compared to MIA PaCa-2 cells. Downregulation of RAGE, pP65, and MDR1 protein expression not only was observed following UA treatment but also was seen in MIA PaCa-2 GEMR cells after transfection with a RAGE siRNA. Remarkably, the enhanced effects of UA coupled with GEM administration dramatically suppressed the RAGE/NF-κB/MDR1 cascade and consequently inhibited subcutaneous tumor growth. Moreover, UA could increase alpha diversity and regulate the composition of gut microbiota, especially in Ruminiclostridium 6. Taken together, these results provide the first direct evidence of MDR1 attenuation and chemosensitivity enhancement through inhibition of the RAGE/NF-κB signaling pathway in vitro and in vivo, implying that UA may be used as an adjuvant for the treatment of pancreatic cancer in the future. 相似文献