Purpose.
To design and develop a drug-delivery system containing a combination of poly(d,l-lactide-co-glycolide) (PLGA) microparticles and alginate hydrogel for sustained release of retinoids to treat retinal blinding diseases that result from an inadequate supply of retinol and generation of 11-cis-retinal.
Methods.
To study drug release in vivo, either the drug-loaded microparticle–hydrogel combination was injected subcutaneously or drug-loaded microparticles were injected intravitreally into Lrat−/− mice. Orally administered 9-cis-retinoids were used for comparison and drug concentrations in plasma were determined by HPLC. Electroretinography (ERG) and both chemical and histologic analyses were used to evaluate drug effects on visual function and morphology.
Results.
Lrat−/− mice demonstrated sustained drug release from the microparticle/hydrogel combination that lasted 4 weeks after subcutaneous injection. Drug concentrations in plasma of the control group treated with the same oral dose rose to higher levels for 6−7 hours but then dropped markedly by 24 hours. Significantly increased ERG responses and a markedly improved retinal pigmented epithelium (RPE)–rod outer segment (ROS) interface were observed after subcutaneous injection of the drug-loaded delivery combination. Intravitreal injection of just 2% of the systemic dose of drug-loaded microparticles provided comparable therapeutic efficacy.
Conclusions.
Sustained release of therapeutic levels of 9-cis-retinoids was achieved in Lrat−/− mice by subcutaneous injection in a microparticle/hydrogel drug-delivery system. Both subcutaneous and intravitreal injections of drug-loaded microparticles into Lrat−/− mice improved visual function and retinal structure.
A novel drug-delivery system was developed for sustained release of therapeutic levels of 9-cis-retinoids. A PLGA microsphere alginate hydrogel combination was used both in vitro and in vivo to evaluate its therapeutic efficacy in retinas of Lrat−/− mice.
doi:10.1167/iovs.12-10279
PMCID: PMC3465014
PMID: 22918645
Aerobactin genes are known to be present in virulent strains and absent from avirulent strains, but contributions of iucC and iucA, which are involved in aerobactin synthesis, to the pathogenicity of avian pathogenic Escherichia coli (APEC) have not been clarified. In this study, effects of double mutants (iucA/iutA or iucC/iutA) compared to those of single mutants (iucA, iucC or iutA) of aerobactin genes on the virulence of APEC strain E058 were examined both in vitro (aerobactin production, ingestion into HD-11 cells, survival in chicken serum) and in vivo (competitive growth against parental strain, colonization and persistence). In competitive co-infection assays, compared to the E058 parental strain, the E058ΔiucA mutant was significantly reduced in the liver, kidney, spleen (all P<0.01), heart and lung (both P<0.001). The E058ΔiutA mutant also was significantly reduced in the liver, lung, kidney (all P<0.01), heart and spleen (both P<0.001). The E058ΔiucC mutant was significantly attenuated in the heart and kidney (both P<0.05) and showed a remarkable reduction in the liver, spleen and lung (P<0.01); meanwhile, both E058ΔiucAΔiutA and E058ΔiucCΔiutA double mutants were sharply reduced as well (P<0.001). In colonization and persistence assays, compared with E058, recovered colonies of E058ΔiucA were significantly reduced from the lung, liver, spleen and kidney (P<0.01) and significantly reduced in the heart (P<0.001). E058ΔiutA was significantly reduced from the heart, lung, liver, spleen and kidney (P<0.01). E058ΔiucC, E058ΔiucAΔiutA and E058ΔiucCΔiutA were significantly decreased in all organs tested (P<0.001). These results suggest that iutA, iucA and iucC play important roles in the pathogenicity of APEC E058.
doi:10.1371/journal.pone.0057794
PMCID: PMC3584046
PMID: 23460907
Geng, Xiumei | Guo, Yufen | Li, Dongfang | Li, Weiwei | Zhu, Chao | Wei, Xiangfei | Chen, Mingliang | Gao, Song | Qiu, Shengqiang | Gong, Youpin | Wu, Liqiong | Long, Mingsheng | Sun, Mengtao | Pan, Gebo | Liu, Liwei
Mass production of reduced graphene oxide and graphene nanoplatelets has recently been achieved. However, a great challenge still remains in realizing large-quantity and high-quality production of large-size thin few-layer graphene (FLG). Here, we create a novel route to solve the issue by employing one-time-only interlayer catalytic exfoliation (ICE) of salt-intercalated graphite. The typical FLG with a large lateral size of tens of microns and a thickness less than 2 nm have been obtained by a mild and durative ICE. The high-quality graphene layers preserve intact basal crystal planes owing to avoidance of the degradation reaction during both intercalation and ICE. Furthermore, we reveal that the high-quality FLG ensures a remarkable lithium-storage stability (>1,000 cycles) and a large reversible specific capacity (>600 mAh g−1). This simple and scalable technique acquiring high-quality FLG offers considerable potential for future realistic applications.
doi:10.1038/srep01134
PMCID: PMC3555088
PMID: 23355949
qnr, aac(6′)-Ib-cr, qepA, and oqxAB genes were detected in 5.7%, 4.9%, 2.6%, and 20.2% of 1,022 Escherichia coli isolates from humans, animals, and the environment, respectively, collected between 1993 and 2010 in China. The prevalence of oqxAB in porcine isolates (51.0%) was significantly higher than that in other isolates. This is the first report of oqxAB-positive isolates from ducks and geese and as early as 1994 from chickens.
doi:10.1128/AAC.06191-11
PMCID: PMC3370760
PMID: 22391545
Yao, Fei | Ariyaratne, Pramila N. | Hillmer, Axel M. | Lee, Wah Heng | Li, Guoliang | Teo, Audrey S. M. | Woo, Xing Yi | Zhang, Zhenshui | Chen, Jieqi P. | Poh, Wan Ting | Zawack, Kelson F. B. | Chan, Chee Seng | Leong, See Ting | Neo, Say Chuan | Choi, Poh Sum D. | Gao, Song | Nagarajan, Niranjan | Thoreau, Hervé | Shahab, Atif | Ruan, Xiaoan | Cacheux-Rataboul, Valère | Wei, Chia-Lin | Bourque, Guillaume | Sung, Wing-Kin | Liu, Edison T. | Ruan, Yijun | Aerts, Jan
Structural variations (SVs) contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET) sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET sequencing data using large DNA inserts of 10–20 kb and compared their characteristics with short insert (1 kb) libraries for their ability to identify SVs. Our results suggest that although short insert libraries bear an advantage in identifying small deletions, they do not provide significantly better breakpoint resolution. In contrast, large inserts are superior to short inserts in providing higher physical genome coverage for the same sequencing cost and achieve greater sensitivity, in practice, for the identification of several classes of SVs, such as copy number neutral and complex events. Furthermore, our results confirm that large insert libraries allow for the identification of SVs within repetitive sequences, which cannot be spanned by short inserts. This provides a key advantage in studying rearrangements in cancer, and we show how it can be used in a fusion-point-guided-concatenation algorithm to study focally amplified regions in cancer.
doi:10.1371/journal.pone.0046152
PMCID: PMC3461012
PMID: 23029419
Objective
To analyze angiographic appearance of hepatocellular carcinoma (HCC) with blood supply from parasitized omental artery (POA), and evaluate the technical feasibility, safety and therapeutic efficacy of chemo-embolization via the POAs.
Methods
A total of 1,221 HCC patients who had undergone chemoembolization procedures were evaluated retrospectively. The evaluated indexes included the incidence rate of POAs, success rate of superselective catheterization, post-reaction after chemoembolization, and the cumulative survival rates.
Results
Totally 1,221 HCC patients had undergone 3,639 chemoembolization procedures, and 32 patients with POAs were enrolled, with 97 POAs found in 76 angiography procedures, giving an incidence rate of 2.09%. POA was observed mostly at the right lobe and left medial lobe except the segment II, and 62 POAs underwent superselective catheterization with microcatheter, giving a success rate of 63.9%. The angiographic appearance was: (1) hypertrophic POAs participating in tumor staining (n=28); (2) stiff and distorted POA (n=11), displaced due to tumor’s oppression (n=8); and (3) defective tumor staining close to either gastrocolic omentum distribution or liver capsule (n=7). In 19 patients, chemoembolization via POAs was performed successfully (A group), while the remaining 13 patients failed (B group). Except 1 acute edema pancreatitis case, no serious complication was recorded. The cumulative survival rates of 6-, 12-, 18- and 24-month were 78.9%, 47.4%, 31.6% and 21.1% respectively for A group; correspondingly, 61.5%, 30.8%, 15.4% and 7.7%% for B group, in which 2 patients died of ruptured HCC.
Conclusion
Chemoembolization with microcatheter via POAs is a relatively safe, feasible and valuable method.
doi:10.1007/s11670-012-0207-7
PMCID: PMC3555289
PMID: 23359452
Hepatocellular carcinoma; Omental artery; Angiography; Chemoembolization
Background
Publicly-funded drug plans often use prior authorization policies to limit drug prescribing. To guide physician prescribing of a class of antibiotics with broad antimicrobial activity (quinolone antibiotics) in accordance with new prescribing guidelines, Alberta’s provincial health ministry implemented a new mechanism for formulary restriction entitled the optional special authorization (OSA) program. We conducted an observational study to determine the impact of this new formulary restriction policy on antimicrobial prescription rates as well as any clinical consequences.
Methods
Quinolone antibiotic use, and adherence with quinolone prescribing guidelines, was assessed before and after implementation of the OSA program in patients with common outpatient infections using an administrative data cohort and a chart review cohort, respectively. At the same time this policy was implemented to limit quinolone prescribing, two new quinolone antibiotics were added to the formulary. Using administrative data, we analysed a total of 397,534 unique index visits with regard to overall antibiotic utilization, and through chart review, we analysed 1681 charts of patients with infections of interest to determine the indications for quinolone usage.
Results
Using segmented regression models adjusting for age, sex and physician enrollment in the OSA program, there was no statistically significant change in the monthly rate of all quinolone use (−3.5 (95% CI −5.5, 1.4) prescriptions per 1000 index visits) following implementation of the OSA program (p = 0.74). There was a significant level change in the rate of quinolone antibiotic use for urinary tract infection (−33.6 (95% CI: -23.8, -43.4) prescriptions and upper respiratory tract infection (−16.1 (95%CI: -11.6, -20.6) prescriptions per 1000 index visits. Among quinolone prescriptions identified on chart review, 42.5% and 58.5% were consistent with formulary guidelines before and after the implementation of the OSA program, respectively (p = 0.002). There was no change in hospitalization, mortality or use of physician services after implementation of the OSA program.
Conclusions
Despite the addition of two new quinolone antibiotics to the formulary, we found that there was no change in the use of quinolones after implementation of a new formulary restriction policy for outpatients with common outpatient infections.
doi:10.1186/1472-6963-12-290
PMCID: PMC3470979
PMID: 22935100
Formulary restriction; Antibiotic; Prior authorization; Prescription drugs
Zhao, Tiansuo | Gao, Song | Wang, Xiuchao | Liu, Jingcheng | Duan, Yitao | Yuan, Zhanna | Sheng, Jun | Li, Shasha | Wang, Feng | Yu, Ming | Ren, He | Hao, Jihui | Datta, Kaustubh
CX3CR1 is an important chemokine receptor and regulates the chemotactic migration of pancreatic ductal adenocarcinoma (PDAC) cells. Up to now, its regulatory mechanism remains largely undefined. Here, we report that hypoxia upregulates the expression of CX3CR1 in pancreatic cancer cells. When hypoxia-inducible factor (HIF)-1α expression was knocked down in vitro and in vivo, the expression of CX3CR1 was significantly decreased. Chromatin immunoprecipitation assay demonstrated that HIF-1α bound to the hypoxia-response element (HRE; 5′-A/GCGTG-3′) of CX3CR1 promoter under normoxia, and this binding was significantly enhanced under hypoxia. Overexpression of HIF-1α significantly upregulated the expression of luciferase reporter gene under the control of the CX3CR1 promoter in pancreatic cancer cells. Importantly, we demonstrated that HIF-1α may regulate cancer cell migration through CX3CR1. The HIF-1α/CX3CR1 pathway might represent a valuable therapeutic target to prevent invasion and distant metastasis in PDAC.
doi:10.1371/journal.pone.0043399
PMCID: PMC3428361
PMID: 22952674
Background
Avian pathogenic Escherichia coli (APEC) and uropathogenic E. coli (UPEC) are the two main subsets of extraintestinal pathogenic E. coli (ExPEC). Both types have multiple iron acquisition systems, including heme and siderophores. Although iron transport systems involved in the pathogenesis of APEC or UPEC have been documented individually in corresponding animal models, the contribution of these systems during simultaneous APEC and UPEC infection is not well described. To determine the contribution of each individual iron acquisition system to the virulence of APEC and UPEC, isogenic mutants affecting iron uptake in APEC E058 and UPEC U17 were constructed and compared in a chicken challenge model.
Results
Salmochelin-defective mutants E058ΔiroD and U17ΔiroD showed significantly decreased pathogenicity compared to the wild-type strains. Aerobactin defective mutants E058ΔiucD and U17ΔiucD demonstrated reduced colonization in several internal organs, whereas the heme defective mutants E058ΔchuT and U17ΔchuT colonized internal organs to the same extent as their wild-type strains. The triple mutant ΔchuTΔiroDΔiucD in both E058 and U17 showed decreased pathogenicity compared to each of the single mutants. The histopathological lesions in visceral organs of birds challenged with the wild-type strains were more severe than those from birds challenged with ΔiroD, ΔiucD or the triple mutants. Conversely, chickens inoculated with the ΔchuT mutants had lesions comparable to those in chickens inoculated with the wild-type strains. However, no significant differences were observed between the mutants and the wild-type strains in resistance to serum, cellular invasion and intracellular survival in HD-11, and growth in iron-rich or iron-restricted medium.
Conclusions
Results indicated that APEC and UPEC utilize similar iron acquisition mechanisms in chickens. Both salmochelin and aerobactin systems appeared to be important in APEC and UPEC virulence, while salmochelin contributed more to the virulence. Heme bounded by ChuT in the periplasm appeared to be redundant in this model, indicating that other periplasmic binding proteins likely contributed to the observed no phenotype for the heme uptake mutant. No differences were observed between the mutants and their wild-type parents in other phenotypic traits, suggesting that other virulence mechanisms compensate for the effect of the mutations.
doi:10.1186/1471-2180-12-143
PMCID: PMC3496646
PMID: 22817680
APEC, Avian pathogenic Escherichia coli; UPEC, Uropathogenic Escherichia coli; Iron acquisition system; Salmochelin; Aerobactin; Heme; Pathogenicity; Chicken challenge model
The purpose of this research was to develop a sensitive and reproducible UPLC-MS/MS method to simultaneously quantify genistein, genistein-7-O-glucuronide (G-7-G), genistein-4’-O-glucuronide (G-4’-G), genistein-4’-O-sulfate (G-4’-S) and genistein-7-Osulfate (G-7-S) in mouse blood samples. After the method was fully validated over a wide linear range, it was applied to quantify the levels of genistein and its metabolites in a mouse bioavailability study. The linear response range were 19.5–10,000 nM for genistein, 12.5–3,200 nM for G-7-G, 20–1280 nM for G-4’-G, 1.95–2,000 nM for G-4’-S, and 1.56–3,200 nM for G-7-S, respectively. The lower limit of quantification (LLOQ) was 4.88, 6.25, 5, 0.98 and 0.78 nM for genistein, G-7-G, G-4’-G, G-4’-S and G-7-S, respectively. Only 20 µl mouse blood sample from i.v. and p.o. administration were needed for analysis because of the high sensitivity of the method. The intra- and inter-day variance is less than 15% and accuracy is within 85–115%. The analysis was finished within 4.5 min. The applicability of this assay was demonstrated and successfully applied for bioavailability study in FVB mouse after i.v. and p.o. administration of 20 mg/kg of genistein, and its oral bioavailability was ~24%.
doi:10.1016/j.jpba.2010.03.011
PMCID: PMC3397253
PMID: 20378296
Genistein; phase II metabolites; pharmacokinetics; UPLC-MS/MS
Background
Muscle protein turnover regulation during cancer cachexia is being rapidly defined, and skeletal muscle mitochondria function appears coupled to processes regulating muscle wasting. Skeletal muscle oxidative capacity and the expression of proteins regulating mitochondrial biogenesis and dynamics are disrupted in severely cachectic ApcMin/+ mice. It has not been determined if these changes occur at the onset of cachexia and are necessary for the progression of muscle wasting. Exercise and anti-cytokine therapies have proven effective in preventing cachexia development in tumor bearing mice, while their effect on mitochondrial content, biogenesis and dynamics is not well understood. The purposes of this study were to 1) determine IL-6 regulation on mitochondrial remodeling/dysfunction during the progression of cancer cachexia and 2) to determine if exercise training can attenuate mitochondrial dysfunction and the induction of proteolytic pathways during IL-6 induced cancer cachexia.
Methods
ApcMin/+ mice were examined during the progression of cachexia, after systemic interleukin (IL)-6r antibody treatment, or after IL-6 over-expression with or without exercise. Direct effects of IL-6 on mitochondrial remodeling were examined in cultured C2C12 myoblasts.
Results
Mitochondrial content was not reduced during the initial development of cachexia, while muscle PGC-1α and fusion (Mfn1, Mfn2) protein expression was repressed. With progressive weight loss mitochondrial content decreased, PGC-1α and fusion proteins were further suppressed, and fission protein (FIS1) was induced. IL-6 receptor antibody administration after the onset of cachexia improved mitochondrial content, PGC-1α, Mfn1/Mfn2 and FIS1 protein expression. IL-6 over-expression in pre-cachectic mice accelerated body weight loss and muscle wasting, without reducing mitochondrial content, while PGC-1α and Mfn1/Mfn2 protein expression was suppressed and FIS1 protein expression induced. Exercise normalized these IL-6 induced effects. C2C12 myotubes administered IL-6 had increased FIS1 protein expression, increased oxidative stress, and reduced PGC-1α gene expression without altered mitochondrial protein expression.
Conclusions
Altered expression of proteins regulating mitochondrial biogenesis and fusion are early events in the initiation of cachexia regulated by IL-6, which precede the loss of muscle mitochondrial content. Furthermore, IL-6 induced mitochondrial remodeling and proteolysis can be rescued with moderate exercise training even in the presence of high circulating IL-6 levels.
doi:10.1186/2044-5040-2-14
PMCID: PMC3431229
PMID: 22769563
FIS1; PGC-1α; Exercise; IL-6r; MFN1; Cachexia; Mitochondria; Muscle; Autophagy
Bioassay-guided fractionation of a solid tumor selective extract of the leaves and twigs of Antheroporum pierrei acquired from the U.S. National Cancer Institute extract repository afforded four new pyranoisoflavones, pierreiones A–D (1 – 4), together with rotenone (5), 12a-hydroxyrotenone (6), and tephrosin (7). The structures of all new compounds were determined on the basis of their spectroscopic data, and the absolute configuration of 1 was assigned with the help of 1H NMR analysis of its Mosher's ester derivatives. Compounds 1, and 5–7 accounted for the majority of the biological activity in terms of either cytotoxicity and/or selective toxicity to solid tumor cell lines. Pierreiones A (1) and B (2) demonstrated solid tumor selectivity with minimal cytotoxicity while pierreione C (3) exhibited no activity.
doi:10.1021/np100763p
PMCID: PMC3371367
PMID: 21452840
Ren, Dabin | Yu, Shengqing | Gao, Song | Peng, Daxin | Petralia, Ronald S. | Muszynski, Artur | Carlson, Russell W. | Robbins, John B. | Tsai, Chao-Ming | Lim, David J. | Gu, Xin-Xing
There is no licensed vaccine available against Moraxella catarrhalis, an exclusive human pathogen responsible for otitis media in children and respiratory infections in adults. We previously developed conjugate vaccine candidates based on lipooligosaccharides (LOSs) of M. catarrhalis serotypes A, B, and C, each of which was shown to cover a portion of the clinical strains. To generate conserved LOS antigens and eliminate a potential autoimmune response to a similar epitope between M. catarrhalis LOS moiety Galα1-4Galβ1-4Glc and human Pk antigen, two LOS mutants from strain O35E were constructed. Mutant O35Elgt5 or O35EgalE revealed a deletion of one or two terminal galactose residues of wild type O35E LOS. Each LOS molecule was purified, characterized, detoxified, and coupled to tetanus toxoid (TT) to form conjugates, namely dLOS-TT. Three subcutaneous immunizations using dLOS-TT from O35Elgt5 or O35EgalE elicited significant increases (a 729- or 1263-fold above the preimmune serum levels) of serum immunoglobulin (Ig)G against O35E LOS in rabbits with an adjuvant or without an adjuvant (an 140- or 140-fold above the preimmune serum levels). Rabbit antisera demonstrated elevated complement-mediated bactericidal activities against the wild type strain O35E. The rabbit sera elicited by O35Elgt5 dLOS-TT were further examined and showed cross bactericidal activity against all additional 19 M. catarrhalis strains and clinical isolates studied. Moreover, the rabbit sera displayed cross-reactivity not only among three serotype strains but also clinical isolates in a whole-cell enzyme-linked immunosorbent assay (ELISA), which was further confirmed under transmission electron microscopy. In conclusion, O35Elgt5 dLOS-TT may act as a vaccine against most M. catarrhalis strains and therefore can be used for further in vivo efficacy studies.
doi:10.1016/j.vaccine.2011.03.102
PMCID: PMC3109615
PMID: 21501641
Moraxella catarrhalis; lipooligosaccharide mutant; conjugate vaccine; cross-reactivity; conserved antigen
In traditional Chinese medicine (TCM), diagnosis of pathology and choice of treatment prescriptions are based on a method of differentiation of signs and symptoms known as syndrome differentiation or ZHENG. The cornerstone of TCM, ZHENG, relies on the gathering of clinical information through inspection, auscultation and olfaction, inquiry, and palpation. However, the biomolecular basis of the ZHENG remains unclear. In this study, we established mouse xenograft pancreatic cancer models with Shi-Re (Dampness-Heat), Pi-Xu (Spleen-Deficiency), or Xue-Yu (Blood-Stasis) ZHENG, which are regarded as the three major ZHENGs in pancreatic cancer. We found that tumors of the different ZHENG models exhibited significantly altered cancer-associated fibroblast (CAF) proliferative activity and tumor-associated macrophage (TAM) infiltration, which led to altered levels of CAF- and TAM-derived secreted cytokines such as SDF-1 and CCL5. The ZHENG model type also significantly influenced tumor growth, and administration of herbal medicine to the ZHENG model modified the tumor microenvironment. Therefore, this study partially unveiled the molecular basis of TCM ZHENG in pancreatic cancer.
doi:10.1155/2012/635702
PMCID: PMC3368347
PMID: 22690248
The purpose of this study was to develop a simultaneous, sensitive and reproducible UPLC-MS/MS method to quantify maackiain and its phase II metabolites, maackiain-sulfate (M-7-S) and maackiain-glucuronide (M-7-G). A Waters BEH C18 column was used with acetonitrile/water as mobile phases. Analysis was performed under negative ionization electrospray mass spectrometer via the multiple reaction monitoring (MRM). The one-step protein precipitation by methanol was used to extract the analytes from plasma. The results showed that the linear response range was 5000 - 9.75 nM for maackiain, M-7-S, and M-7-G. The lower limit of detection (LLOD) was 4.88 nM for these three analytes. The intra-day variance is less than 15% and accuracy is in 85.7–102.0 %. The inter-day variance is less than 11.2 % and accuracy is in 89.6–122.2 %. The analysis was done within 4.0 min. Only 20 µl of blood is needed for analysis due to the high sensitivity of this method. The validated method was used to pharmacokinetic study in A/J mouse, maackiain Caco-2 cell culture model experiment, and maackiain glucuronidation/ sulfation metabolism studies. The applications revealed that this method can be used for maackiain, M-7-S, and M-7-G analysis in both bioequivalent buffer and in blood.
doi:10.1016/j.jpba.2011.01.015
PMCID: PMC3085908
PMID: 21349678
Maackiain; Maackiain-7-glucuronide; Maackiain-7-sulfate; Pharmacokinetics; UPLC-MS/MS
The biosynthesis of nanoparticles has received increasing attention due to the growing need to develop safe, cost-effective and environmentally friendly technologies for nano-materials synthesis. In this report, silver nanoparticles (AgNPs) were synthesized using a reduction of aqueous Ag+ ion with the culture supernatants of Aspergillus terreus. The reaction occurred at ambient temperature and in a few hours. The bioreduction of AgNPs was monitored by ultraviolet-visible spectroscopy, and the AgNPs obtained were characterized by transmission electron microscopy and X-ray diffraction. The synthesized AgNPs were polydispersed spherical particles ranging in size from 1 to 20 nm and stabilized in the solution. Reduced nicotinamide adenine dinucleotide (NADH) was found to be an important reducing agent for the biosynthesis, and the formation of AgNPs might be an enzyme-mediated extracellular reaction process. Furthermore, the antimicrobial potential of AgNPs was systematically evaluated. The synthesized AgNPs could efficiently inhibit various pathogenic organisms, including bacteria and fungi. The current research opens a new avenue for the green synthesis of nano-materials.
doi:10.3390/ijms13010466
PMCID: PMC3269698
PMID: 22312264
silver nanoparticles; Aspergillus terreus; biosynthesis; NADH
Hu, Zhenhua | Gao, Song | Gao, Jian | Hou, Rui | Liu, Chuan | Liu, Juanjuan | Li, Beibei | Liu, Dawo | Zhang, Shulan | Lin, Bei
Objective
To measure Lewis y and integrin α5β1 expression in epithelial ovarian carcinoma and to correlate the levels of these molecules with ovarian carcinoma chemotherapy and prognosis.
Methods
The study population included 34 ovarian carcinoma patients with chemotherapeutic drug-resistance, six partially drug-sensitive cases, and 52 drug-sensitive cases (92 total). Immunochemistry was used to determine expression of Lewis y antigen and integrin α5β1 in ovarian carcinoma tissues, and correlation of these molecules with chemotherapy resistance was further investigated, Multi-factor logistic regression analysis was applied to investigate: age, surgical stage, grade, subtype of patient cases, metastasis of lymph nodes, residual tumor size, expression levels of Lewis y antigen and integrin α5β1 correlation with ovarian carcinoma chemotherapy resistance.
Results
The expression rates of Lewis y antigen and integrins α5 and β1 were significantly greater in the drug-resistant group (91.17%, 85.29%, 88.24%) than the partially sensitive (50.00%, 33.33%, 50.00%) or sensitive groups (61.54%, 57.69%, 55.77%). Binary logistic regression analysis revealed that surgical stage, residual tumor size, and expression of integrin α5 and Lewis y in ovarian carcinoma tissues were independent risk factors for chemotherapeutic drug resistance.
Conclusions
Overexpression of Lewis y and integrin α5 are strong risk factors for chemotherapeutic drug resistance in ovarian carcinoma patients.
doi:10.3390/ijms131215588
PMCID: PMC3546651
PMID: 23443083
integrins; Lewis y antigen; ovarian caricinoma; chemoresistance
LI, FEI-FEI | LIU, JUAN-JUAN | LIU, DA-WO | LIN, BEI | HAO, YING-YING | CONG, JIAN-PING | ZHU, LIAN-CHENG | GAO, SONG | ZHANG, SHU-LAN | IWAMORI, MASAO
LeY (Lewis Y) is a difucosylated oligosaccharide carried by glycoconjugates on the cell surface. Elevation of LeY is frequently observed in epithelial-derived cancers and is correlated to pathological staging and prognosis. To study the role of LeY on cancer cells, a stably LeY-overexpressing cell line, RMG-I-H, was developed previously by transfection of the α1,2-fucosyltransferase gene, a key enzyme that catalyzes the synthesis of LeY, into ovarian carcinoma-derived RMG-I cells. Our studies have shown that LeY is involved in the changes in biological behavior of RMG-I-H cells. However, the mechanism is still largely unknown. In this study, we determined the structural relationship and co-localization between LeY and TβRI/TβRII, respectively, and the potential cellular signaling mechanism was also investigated. We found that both TβRI and TβRII contain the LeY structure, and the level of LeY in TβRI and TβRII in RMG-I-H cells was significantly increased. Overexpression of LeY up-regulates the phosphorylation of ERK, Akt and down-regulates the phosphorylation of Smad2/3. In addition, the phosphorylation intensity was attenuated significantly by LeY monoantibody. These findings suggest that LeY is involved in the changes in biological behavior through TGF-β receptors via Smad, ERK/MAPK and PI3K/Akt signaling pathways. We suggest that LeY may be an important composition of growth factor receptors and could be an attractive candidate for cancer diagnosis and treatment.
doi:10.3892/ijo.2011.1296
PMCID: PMC3584585
PMID: 22179544
Lewis Y; p42/44 mitogen-activated protein kinase; phosphoinositide 3-kinase; Smad; transforming growth factor β type I (II) receptor
WANG, SHENG-TAN | LIU, JUAN-JUAN | WANG, CHANG-ZHI | LIN, BEI | HAO, YING-YING | WANG, YI-FEI | GAO, SONG | QI, YUE | ZHANG, SHU-LAN | IWAMORI, MASAO
Lewis y is a difucosylated oligosaccharide carried by glycoconjugates on the cell surface. Elevation of Lewis y is frequently observed in epithelial-derived cancers. This study aimed to detect the expression and clinical significance of the Lewis y antigen and TGF-β1 (transforming growth factor β1) in ovarian epithelial tumors, and to evaluate the correlation between them. Immunohistochemical staining was used to detect the expression of Lewis y antigen and TGF-β1 in 60 cases of ovarian epithelial malignant tumors, 20 cases of borderline ovary tumors, 20 cases of benign ovary tumors and 10 cases of normal ovarian tissues. An immunofluorescence double labeling method was also used to detect the correlation between Lewis y antigen and TGF-β1. The positive rates of Lewis y antigen in ovarian epithelial cancer tissues was 88.33%, significantly higher compared to those of borderline ovarian tumors (60.00%) (P<0.05), benign ovarian tumors (35.00%) (P<0.01) and normal ovarian tissues (0%) (P<0.01). Its expression was not associated with clinical parameters; the positive rates of TGF-β1 in ovarian epithelial cancers were 78.33%, significantly higher compared to those of benign ovarian tumors (65.00%) (P<0.05) and normal ovarian tissues (40.00%) (P<0.05); the positive rates of the TGF-β1 and Lewis y were not associated with metastasis of lymph nodes and histological types, differentiation degree and clinical stage (P>0.05). Expression of Lewis y antigen and TGF-β1 was significantly positively associated with epithelial carcinoma. Close correlation between Lewis y, TGF-β1 and ovarian cancer was observed. Altered expression of Lewis y antigen may cause changes in TGF-β1 expression. Lewis y can increase the growth of ovarian cancer cells and the invasion ability by promoting TGF-β1 abnormal expression and by promoting angiogenesis and a change in its signal transduction pathway. This study provides theoretical evidence for the development of ovarian cancer biological treatments.
doi:10.3892/or.2011.1575
PMCID: PMC3583523
PMID: 22138668
ovarian epithelial carcinoma; transforming growth factor β1; Lewis y; immunohistochemistry; immunofluorescence double labeling method
Objective
Endocervical curettage (ECC) specimens obtained during colposcopy can detect cervical cancer and precursors otherwise missed by biopsy alone; but the procedure can be painful and reduce compliance with needed follow-up. ECC is routinely performed in the Calgary Health Region colposcopy clinics, permitting a look at its real-world utility.
Study Design
We analyzed pathology and colposcopy reports from 2003–2007. We calculated the added diagnostic utility of ECC compared to cervical biopsy alone.
Results
ECC increased the diagnostic yield of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in 1.01% of 13,115 colposcopically-guided biopsy exams. Therefore, 99 ECC specimens were taken to detect one additional CIN2+. ECC detected 5.4% of 2,443 CIN2+ cases otherwise missed by biopsy alone. Utility was greatest among women aged 46+ referred after a high-grade cytology.
Conclusions
ECC is rarely informative when used routinely in colposcopic practice. Older women referred after high-risk cytology benefit most from ECC.
doi:10.1016/j.ajog.2010.06.048
PMCID: PMC2975767
PMID: 20800216
cervical intraepithelial neoplasia; colposcopy; curettage; diagnosis; endocervical sampling
Abstract
Scaffolding, the problem of ordering and orienting contigs, typically using paired-end reads, is a crucial step in the assembly of high-quality draft genomes. Even as sequencing technologies and mate-pair protocols have improved significantly, scaffolding programs still rely on heuristics, with no guarantees on the quality of the solution. In this work, we explored the feasibility of an exact solution for scaffolding and present a first tractable solution for this problem (Opera). We also describe a graph contraction procedure that allows the solution to scale to large scaffolding problems and demonstrate this by scaffolding several large real and synthetic datasets. In comparisons with existing scaffolders, Opera simultaneously produced longer and more accurate scaffolds demonstrating the utility of an exact approach. Opera also incorporates an exact quadratic programming formulation to precisely compute gap sizes (Availability: http://sourceforge.net/projects/operasf/).
doi:10.1089/cmb.2011.0170
PMCID: PMC3216105
PMID: 21929371
parametric complexity; genome assembly; quadratic programming; scaffolding
Purpose
To quantitate and predict colon-specific 9-aminocamptothecin (9-AC) release from the N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer–9-AC conjugate and its absorption behavior after oral administration in rats.
Methods
Drug distribution in the gastrointestinal (GI) tract and the plasma concentration-time profile of 9-AC released from the HPMA copolymer conjugate were predicted using the degradation, transit, and absorption rate constants in cecum. The fate of 9-AC in cecum and liver was measured by in-situ cecum absorption and liver perfusion.
Results
Following oral administration of the conjugate, 9-AC was released rapidly in cecum. Based on the pharmacokinetic model, up to 60% of the dose was in the cecum at ∼6 h, and 7% of the dose still remained there at 24 h. The predicted plasma concentration curve for released 9-AC after an oral dose of 3 mg/kg of 9-AC equivalent increased gradually and reached a peak of 98 nM at 7 h, then started decreasing slowly to 16 nM at 24 h. The bioavailability value was estimated as 0.31 after the first-pass elimination.
Conclusions
A pharmacokinetic model delineated the impact of GI transit, drug absorption rate, and first-pass metabolism on drug disposition following oral administration of HPMA copolymer–9-AC conjugate in rats.
doi:10.1007/s11095-007-9465-3
PMCID: PMC3136142
PMID: 17929146
absorption prediction; colon-specific drug delivery; HPMA copolymer–9-aminocamptothecin conjugate; oral dosing; pharmacokinetic modeling
Background
The mitochondrion is an essential organelle which plays important roles in diverse biological processes, such as metabolism, apoptosis, signal transduction and cell cycle. Characterizing protein-protein interactions (PPIs) that execute mitochondrial functions is fundamental in understanding the mechanisms underlying biological functions and diseases associated with mitochondria. Investigations examining mitochondria are expanding to the system level because of the accumulation of mitochondrial proteomes and human interactome. Consequently, the development of a database that provides the entire protein interaction map of the human mitochondrion is urgently required.
Results
InterMitoBase provides a comprehensive interactome of human mitochondria. It contains the PPIs in biological pathways mediated by mitochondrial proteins, the PPIs between mitochondrial proteins and non-mitochondrial proteins as well as the PPIs between mitochondrial proteins. The current version of InterMitoBase covers 5,883 non-redundant PPIs of 2,813 proteins integrated from a wide range of resources including PubMed, KEGG, BioGRID, HPRD, DIP and IntAct. Comprehensive curations have been made on the interactions derived from PubMed. All the interactions in InterMitoBase are annotated according to the information collected from their original sources, GenBank and GO. Additionally, InterMitoBase features a user-friendly graphic visualization platform to present functional and topological analysis of PPI networks identified. This should aid researchers in the study of underlying biological properties.
Conclusions
InterMitoBase is designed as an integrated PPI database which provides the most up-to-date PPI information for human mitochondria. It also works as a platform by integrating several on-line tools for the PPI analysis. As an analysis platform and as a PPI database, InterMitoBase will be an important database for the study of mitochondria biochemistry, and should be particularly helpful in comprehensive analyses of complex biological mechanisms underlying mitochondrial functions.
doi:10.1186/1471-2164-12-335
PMCID: PMC3142533
PMID: 21718467
The purposes of this study were to determine content uniformity of phenolics in the St John's Wort (SJW) supplements, and to demonstrate how variations in the product matrices affect their absorption and efflux. LC and LC-MS/MS methods were used to determine the phenolic contents of twelve different products purchased locally or from the internet. Three representative extracts were further submitted to Caco-2 cell transport experiment and transport of rutin, hyperoside, and isoquercitrin were evaluated. The results indicated that twelve different products displayed twelve different HPLC fingerprints, but all products contained the following major compounds: rutin, hyperoside, isoquercitrin, quercitrin, quercetin, and amentoflavone. The content uniformity of these major compounds was poor across products, with the smallest difference in the amounts of amentoflavone (2.6 folds) and largest difference in that of isoquercitrin (28.8 folds). The Caco-2 experiments indicated transport of rutin was vectorial, with the permeabilities varied about 2 folds in both direction of transport. The vectorial permeabilities of hyperoside and isoquercitrin were similarly different. Use of efflux transporter inhibitors studies suggested that MRP2 was involved in isoquercitrin's efflux and the product matrix affected the extent of its efflux. In conclusion, different SJW supplements had highly variable contents of phenolics, and the variability in product matrix and phytochemical compositions affected the permeabilities of key phenolics across the Caco-2 monolayers, which may further impact their bioavailabilities. Therefore, standardization will be necessary to ensure safe and efficacious use of supplements such as SJW.
doi:10.1021/jf904459u
PMCID: PMC2919490
PMID: 20450158
St John's Wort; Dietary Supplement; Standardization; Caco-2 cell model; Bioavailability; MRP
Phenolics including many polyphenols and flavonoids have the potentials to become chemoprevention and chemotherapy agents. However, poor bioavailability limits their biological effects in vivo. This paper reviews the factors that affect phenolics absorption and their bioavailabilities from the points of view of their physicochemical properties and disposition in the gastrointestinal tract. The up-to-date research data suggested that solubility and metabolism are the primary reasons that limit phenolic aglycones’ bioavailability although stability and poor permeation may also contribute to the poor bioavailabilities of the glycosides. Future investigations should further optimize phenolics’ bioavailabilities and realize their chemopreventive and chemotherapeutic effects in vivo.
PMCID: PMC2919492
PMID: 20370701
Chemoprevention, Chemotherapy; Phenolic; Bioavailability Challenge; Polyphenol; Flavonoids