The capacitors in high-voltage direct-current (HVDC) converter stations radiate a lot of audible noise which can reach higher than 100 dB. The existing noise level prediction methods are not satisfying enough. In this paper, a new noise level prediction method is proposed based on a frequency response function considering both electrical and mechanical characteristics of capacitors. The electro-mechanical frequency response function (EMFRF) is defined as the frequency domain quotient of the vibration response and the squared capacitor voltage, and it is obtained from impulse current experiment. Under given excitations, the vibration response of the capacitor tank is the product of EMFRF and the square of the given capacitor voltage in frequency domain, and the radiated audible noise is calculated by structure acoustic coupling formulas. The noise level under the same excitations is also measured in laboratory, and the results are compared with the prediction. The comparison proves that the noise prediction method is effective.
TFIIB (transcription factor IIB) is a transcription factor that provides a bridge between promoter-bound TFIID and RNA polymerase II, and it is a target of various transcriptional activator proteins that stimulate the pre-initiation complex assembly. The localization and/or attachment matrix of TFIIB in the cytoplast is not well understood. This study focuses on the function of TFIIB and its interrelationship with α-tubulins in a mouse model. During oocyte maturation TFIIB distributes throughout the entire nucleus of the germinal vesicle (GV). After progression to GV breakdown (GVBD), TFIIB and α-tubulin co-localize and accumulate in the vicinity of the condensed chromosomes. During the MII stage, the TFIIB signals are more concentrated at the equatorial plate and the kinetochores. Colcemid treatment of oocytes disrupts the microtubule (MT) system, although the TFIIB signals are still present with the altered MT state. Injection of oocytes with TFIIB antibodies and siRNAs causes abnormal spindle formation and irregular chromosome alignment. These findings suggest that TFIIB dissociates from the condensed chromatids and then tightly binds to microtubules from GVBD to the MII phase. The assembly and disassembly of TFIIB may very well be associated with and driven by microtubules. TFIIB maintains its contact with the α-tubulins and its co-localization forms a unique distribution pattern. Depletion of Tf2b in oocytes results in a significant decrease in TFIIB expression, although polar body extrusion does not appear to be affected. Knockdown of Tf2b dramatically affects subsequent embryo development with more than 85% of the embryos arrested at the 2-cell stage. These arrested embryos still maintain apparently normal morphology for at least 96h without any obvious degeneration. Analysis of the effects of TFIIB in somatic cells by co-transfection of BiFC plasmids pHA-Tf2b and pFlag-Tuba1α further confirms a direct interaction between TFIIB and α-tubulins.
The extract of UIC 10035, a strain obtained from a sample collected near the town of Homestead, south Florida, showed antiproliferative activity against MDA-MB-435 cells. Bioassay-guided fractionation led to the isolation of a series of cyclic lipodecapeptides, named minutissamides E - L (1 – 8). The planar structures were determined by analysis of HRESIMS, tandem MS, and 1D and 2D NMR data, and the stereoconfigurations were assigned by LC-MS analysis of the Marfey's derivatives after acid hydrolysis. Minutissamides E - L (1 – 8) exhibited antiproliferative activity against MDA-MB-435 cells with IC50 values ranging between 1 and 10 μM. The structures of minutissamides E - L (1 – 8) were closely related with those of the previously reported lipopeptides, puwainaphycins A - E and minutissamides A - D, characterized by the presence of a lipophilic -amino acid and three non-standard amino acids NMeAsn, OMeThr and Dhb (, -dehydro- -aminobutyric acid). The strain UIC 10035 was designated as cf. Anabaena sp. on the basis of morphological and 16S rRNA gene sequence analyses.
Cyanobactreia; Anabaena; Cyclic lipopeptides; MDA-MB-435; Antiproliferative activity
Various types of lignocellulosic wastes extensively used in biofuel production were provided to assess the potential of EXLX1 as a cellulase synergist. Enzymatic hydrolysis of natural wheat straw showed that all the treatments using mixtures of cellulase and an optimized amount of EXLX1, released greater quantities of sugars than those using cellulase alone, regardless of cellulase dosage and incubation time. EXLX1 exhibited different synergism and binding characteristics for different wastes, but this can be related to their lignocellulosic components. The cellulose proportion could be one of the important factors. However, when the cellulose proportion of different biomass samples exhibited no remarkable differences, a higher synergism of EXLX1 is prone to occur on these materials, with a high proportion of hemicellulose and a low proportion of lignin. The information could be favorable to assess whether EXLX1 is effective as a cellulase synergist for the hydrolysis of the used materials. Binding assay experiments further suggested that EXLX1 bound preferentially to alkali pretreated materials, as opposed to acid pretreated materials under the assay condition and the binding preference would be affected by incubation temperature.
Despite the success of imatinib and other tyrosine kinase inhibitors (TKIs), chronic myeloid leukemia (CML) remains largely incurable, and a number of CML patients die due to Abl mutation-related drug resistance and blast crisis. The aim of this study was to evaluate proliferation inhibition and apoptosis induction by down-regulating PPP2R5C gene expression in the imatinib-sensitive and imatinib-resistant CML cell lines K562, K562R (imatinib resistant without an Abl gene mutation), 32D-Bcr-Abl WT (imatinib-sensitive murine CML cell line with a wild type Abl gene) and 32D-Bcr-Abl T315I (imatinib resistant with a T315I Abl gene mutation) and primary cells from CML patients by RNA interference. PPP2R5C siRNAs numbered 799 and 991 were obtained by chemosynthesis. Non-silencing siRNA scrambled control (SC)-treated, mock-transfected, and untreated cells were used as controls. The PPP2R5C mRNA and protein expression levels in treated CML cells were analyzed by quantitative real-time PCR and Western blotting, and in vitro cell proliferation was assayed with the cell counting kit-8 method. The morphology and percentage of apoptosis were revealed by Hoechst 33258 staining and flow cytometry (FCM). The results demonstrated that both siRNAs had the best silencing results after nucleofection in all four cell lines and primary cells. A reduction in PPP2R5C mRNA and protein levels was observed in the treated cells. The proliferation rate of the PPP2R5C-siRNA-treated CML cell lines was significantly decreased at 72 h, and apoptosis was significantly increased. Significantly higher proliferation inhibition and apoptosis induction were found in K562R cells treated with PPP2R5C-siRNA799 than K562 cells. In conclusion, the suppression of PPP2R5C by RNA interference could inhibit proliferation and effectively induce apoptosis in CML cells that were either imatinib sensitive or resistant. Down-regulating PPP2R5C gene expression might be considered as a new therapeutic target strategy for CML, particularly for imatinib-resistant CML.
CML; Imatinib resistant; PPP2R5C; RNA interference; Apoptosis; Cell proliferation
Stem cells play an essential role in embryonic development, cell differentiation and tissue regeneration. Tissue homeostasis in adults is maintained by adult stem cells resident in the niches of different tissues. As one kind of adult stem cell, epidermal stem cells have the potential to generate diversified types of progeny cells in the skin. Although its biology is still largely unclarified, epidermal stem cells are widely used in stem cell research and regenerative medicine given its easy accessibility and pluripotency. Despite the same genome, cells within an organism have different fates due to the epigenetic regulation of gene expression. In this review, we will briefly discuss the current understanding of epigenetic modulation in epidermal stem cells.
epidermal stem cell; epigenetic modification; histone methylation; DNA methylation; noncoding RNA; microRNA; long noncoding RNA
As part of an ongoing investigation of filamentous fungi for anticancer leads, an active culture was identified from the Mycosynthetix library (MSX 70741, of the order Hypocreales, Ascomycota). The fungal extract exhibited cytotoxic activity against the H460 (human non-small cell lung carcinoma) cell line, and bioactivity-directed fractionation yielded peptaibols 1–12 and harzianums A (13) and B (14). Structure elucidation of 1–12 was facilitated by high-resolution MS/MS obtained on a Thermo LTQ Orbitrap XL using Higher-Energy Collisional Dissociation (HCD) and by high field NMR (950 MHz). The absolute configuration was determined by Marfey’s analysis of the individual amino acids; the time required for such analysis was decreased via the development of a 10 min UPLC method. The isolated peptaibols (1–12), along with three other peptaibols isolated and elucidated from a different fungus (MSX 57715) of the same Order (15–17), were examined for activity in a suite of biological assays, including those for cytotoxic, antibacterial, and anthelmintic activities.
peptaibols; cytotoxicity; anthelmintic; Hypocreales; Higher-Energy Collisional Dissociation (HCD)
The cell extract of a cultured terrestrial Nostoc sp. (UIC 10062), obtained from a sample collected at Grand Mere State Park in Michigan, displayed antiproliferative activity against the HT-29 human colon cancer cell line. Bioactivity-guided fractionation of the cell extract, combined with LC-MS analysis, led to the isolation of two cyclophanes, named merocyclophanes A and B (1 and 2). Their structures were determined by various spectroscopic techniques including HRESIMS, and 1D and 2D NMR analyses. The stereoconfiguration was assigned on the basis of X-ray crystallographic and CD analyses. The structures of merocyclophanes A and B (1 and 2) established a hitherto unknown [7.7]paracyclophane skeleton in nature, as characterized by α-branched methyls at C-1/14. Merocyclophanes A and B (1 and 2) displayed antiproliferative activity against the HT-29 human colon cancer cell line with IC50 values of 3.3 and 1.7 µM, respectively.
Nostoc sp.; Cyanobacterium; Antiproliferative activity; HT-29 human colon cancer cells; [7.7]paracyclophanes
Chemical investigation of the cultured cyanobacterium Fischerella sp. (SAG strain number 46.79) led to the isolation of four nitrile-containing indole alkaloids, namely 12-epi-fischerindole I nitrile (1), deschloro 12-epi-fischerindole I nitrile (2), 12-epi-fischerindole W nitrile (3), and deschloro 12-epi-fischerindole W nitrile (4) along with a known metabolite hapalosin. The structures were determined by detailed spectroscopic analyses on the basis of 1D and 2D NMR and HRESIMS data. All isolates were evaluated for cytotoxicity against human cancer cells and for 20S proteasome inhibition. Deschloro 12-epi-fischerindole I nitrile (2) was found to be weakly cytotoxic against HT-29 cells with an ED50 value of 23 μM. Hapalosin showed weak cytotoxicity against HT-29 and MCF-7 cells with ED50 values of 22 and 27 μM, respectively, as well as moderate 20S proteasome inhibition with an IC50 value of 12 μM. Compounds 1-4 all contain a nitrile moiety instead of the isonitrile found in all fischerindoles reported to date. Compounds 3 and 4 also display a new carbon skeleton, in which a six-membered ring replaces the five-membered ring normally found in fischerindole-type alkaloids.
Metamorphosis, the transformation of one normal tissue or organ system into another, is a biological process rarely studied in higher vertebrates or mammals, but exemplified pathologically by the extremely disabling autosomal dominant disorder fibrodysplasia ossificans progressiva (FOP). The recurrent single nucleotide missense mutation in the gene encoding activin receptor IA/activin-like kinase-2 (ACVR1/ALK2), a bone morphogenetic protein type I receptor that causes skeletal metamorphosis in all classically affected individuals worldwide, is the first identified human metamorphogene. Physiological studies of this metamorphogene are beginning to provide deep insight into a highly conserved signaling pathway that regulates tissue stability following morphogenesis, and that when damaged at a highly specific locus (c.617G > A; R206H), and triggered by an inflammatory stimulus permits the renegade metamorphosis of normal functioning connective tissue into a highly ramified skeleton of heterotopic bone. A comprehensive understanding of the process of skeletal metamorphosis, as revealed by the rare condition FOP, will lead to the development of more effective treatments for FOP and, possibly, for more common disorders of skeletal metamorphosis.
morphogen; metamorphogene; ACVR1; fibrodysplasia ossificans progressiva (FOP); bone morphogenetic protein (BMP); BMP receptor; heterotopic ossification
Human serum albumin (HSA) and human parathyroid hormone (1-34) [PTH (1-34)] fusion protein [HSA/PTH (1-34)] is a promising long-acting form of PTH (1-34) for osteoporosis treatment. Secretory expression of intact HSA/PTH (1-34) in Pichia pastoris GS115 was accompanied by two degradation fragments, with molecular weights around 66 kDa, in addition to the well-known ~45 kDa HSA-truncated fragment, resulting in a low yield of intact protein. In this study, two internal cleavage sites were identified in the PTH (1-34) portion of the fusion protein by Western Blot analysis. To minimize proteolytic cleavages, several protease genes including PEP4 (encoding proteinase A), PRB1 (proteinase B) and seven YPSs genes (yapsin family members) were knocked out respectively by disruption of the individual genes and the selective combinations. Reduced degradation was observed by single disruption of either PEP4 gene or YPS1 gene, and the lowest level of degradation was observed in a pep4△yps1△ double disruptant. After 72 h of induction, more than 80 % of the HSA/PTH (1-34) secreted by the pep4△yps1△ double disruptant remained intact, in comparison to only 30 % with the wild-type strain.
Electronic supplementary material
The online version of this article (doi:10.1007/s10295-013-1264-8) contains supplementary material, which is available to authorized users.
Heterologous protein expression; Proteolytic degradation; Pichia pastoris; Yapsin; Proteinase A
A previous study has demonstrated a significant decrease in the TCRζ gene expression level in chronic myeloid leukemia (CML); thus, we further investigated the expression of TCRζ-regulating factors, the distribution of the TCRζ 3' untranslated region (3'-UTR) splice variants, and the expression level and correlation of the alternative splicing factor/splicing factor 2 (ASF/SF-2), FcεRIγ and ZAP-70 genes. TCRζ 3'-UTR splice variants were identified in peripheral blood mononuclear cells (PBMCs) from 14 healthy individuals, 40 patients with CML and 22 patients with CML in complete remission (CML-CR) by RT-PCR. The expression level of the TCRζ, FcεRIγ, ASF/SF-2 and ZAP-70 genes was analyzed by real-time quantitative PCR. While the expression of TCRζ gene in the CML group was significantly lower than that in the healthy individual and CML-CR groups, a significantly higher expression of the FceRIγ and ASF/SF-2 genes was found in the CML group. Two types of splicing forms were detected in all of the healthy individual CML-CR cases: wild type (WT) TCRζ 3'-UTR and alternatively splieced (AS) TCRζ 3'-UTR which have been alternatively splieced in the WT TCRζ 3'-UTR . However, 35% of the CML cases contained only the wild type TCRζ 3'-UTR isoform. Based on the TCRζ 3'-UTR isoform expression characteristic, we divided the patients with CML into two subgroups: the WT+AS- CML group, containing patients that express only the wild type TCRζ 3'-UTR, and the WT+AS+ CML group, which contained patients that expressed two TCRζ 3'-UTR isoforms. A significantly different ASF/SF-2 and FcεRIγ gene expression pattern was found between the WT+AS- and WT+AS+CML groups. We concluded that defective TCRζ expression may be characterized in the WT+AS-and WT+AS+CML subgroups by the different gene expression pattern. The overexpression of ASF/SF2, which alternatively splices the TCRζ 3’-UTR, is thought to participate in feedback regulation. The characteristics of TCRζ 3'-UTR alternative splicing may be a novel immunological marker for the evaluation of the CML immune status.
ASF/SF-2gene; TCRζ3′-UTR; TCRζ gene; FcεRIγ gene; Chronic myeloid leukemia; Real-time PCR
Two new cyclodepsipeptides (1 and 2), two new sesquiterpenoids (3 and 4), and the known compounds guangomide A (5), roseotoxin S, and three simple trichothecenes were isolated from the cytotoxic organic extract of a terrestrial filamentous fungus, Trichothecium sp. The structures were determined using NMR spectroscopy and mass spectrometry. Absolute configurations of the cyclodepsipeptides were established by employing chiral HPLC, while the relative configurations of 3 and 4 were determined via NOESY data. The isolation of guangomide A was of particular interest, since it was reported previously from a marine derived fungus.
Background and methods
In order to characterize the expression pattern of SALL4, BMI-1 and ABCA3 genes in patients with myeloid leukemia and those who achieved complete remission (CR) after chemotherapy. Real-time PCR was used to determine the expression level of these genes in peripheral blood mononuclear cells from 24 patients with AML, eight patients with AML-CR, 13 patients with CML in the chronic phase (CML-CP), 12 patients with CML in blast crisis (CML-BC), 13 patients with CML-CR and 11 healthy individuals (HI).
Overexpression of the BMI-1 gene was found in the AML, CML-CP and CML-BC groups as compared with HI group, while the BMI-1 expression level was lower in patients who achieved CR. In contrast, significantly increased SALL4 expression was only found in AML group, additionally, SALL4 expression was lower in the CML-CP and CML-CR groups compared with the HI group, while the SALL4 expression level in the CML-BC group was higher and significantly greater than that in the CML-CP and CML-CR groups. Moreover, a positive correlation between the expression of SALL4 and BMI-1 genes was found in samples from most groups. There was no significant difference of ABCA3 expression level in AML and CML-BC group in comparison with HI group. Interestingly, the ABCA3 expression level was significantly decreased in the CML-CP, AML-CR and CML-CR in comparison with the HI group. Moreover, the ABCA3 expression level in all of the CR groups was lower than that in their corresponding groups.
These results describe the altered SALL4, ABCA3 and BMI-1 expression pattern in different phases of myeloid leukemia, which may relate to the development and progression to different diseases. SALL4 expression was strongly correlated with BMI-1 in most of the myeloid leukemia patient groups, providing a potential link between SALL4 and BMI-1 in leukemogenesis.
SALL4 gene; BMI-1 gene; Real-time PCR; AML; CML
A fungal extract (MSX 63619), from the Mycosynthetix library of over 50,000 fungi, displayed promising cytotoxicity against a human tumor cell panel. Bioactivity-directed fractionation led to the isolation of an o-pyranonaphthoquinone decaketide, which we termed obionin B (1). The structure of 1 was deduced via spectroscopic and spectrometric techniques. The IC50 value of 1 was moderate, ranging from 3 to 13 μM, depending on the cell line tested.
Polyketide; Cytotoxicity; Pleosporales; o-Naphthoquinone
In the present study, the effect of a borneol/menthol eutectic mixture (25:75) and microemulsion on the absorption of daidzein in rat intestinal membrane was evaluated. The microemulsion formulation was composed of ethyl oleate (oil), Cremophor RH40 (surfactant), PEG400 (co-surfactant), and water. The borneol/menthol eutectic mixture and its microemulsion were found to enhance the intestinal absorption of daidzein in vitro. A diffusion chamber system with isolated rat intestinal membranes was used. In contrast, verapamil (0.3 mM), a typical P-glycoprotein inhibitor, showed no effect on the absorption of daidzein by this system. A pharmacokinetic study was conducted in rats. After oral administration of daidzein at a dose of 10 mg/kg in the form of either borneol/menthol eutectic mixtures or suspension, the relative bioavailability of borneol/menthol eutectic mixtures and microemulsion was enhanced by about 1.5- and 3.65-fold, respectively, compared with a daidzein suspension. In conclusion, a borneol/menthol eutectic mixture can enhance the absorption of daidzein, although the mechanism of absorption enhancement is still unclear.
absorption enhancer; bioavailability; borneol/menthol eutectic mixture; daidzein; microemulsion
Four cyclic decapeptides, minutissamides A-D (1 - 4), were isolated from the cultured cyanobacterium Anabaena minutissima (UTEX 1613). The planar structures were determined using various spectroscopic techniques including HRESIMS, and 1D and 2D NMR experiments. The absolute configurations of the α-amino acid residues were assigned using Marfey's method after acid hydrolysis. The absolute configuration of a β-amino acid residue was assigned by a combination of the advanced Marfey's method, J-based configurational analysis and ROE spectroscopic analysis. The structures of minutissamides A-D (1 - 4) were characterized by the presence of three non-standard α-amino acid residues (two α,β-dehydro-α-aminobutyric acids and one N-methylated Asn) and one β-amino acid residue (2-hydroxy-3-amino-4-methyl dodecanoic acid or 2-hydroxy-3-amino-4-methyl hexadecanoic acid). Minutissamides A-D (1 - 4) exhibited antiproliferative activity against the HT-29 human colon cancer cell line with IC50 values of 2.0, 20.0, 11.8 and 22.7 μM, respectively.
Two new xanthone-anthraquinone heterodimers, acremoxanthone C (5) and acremoxanthone D (2), have been isolated from an extract of an unidentified fungus of the Order Hypocreales (MSX 17022) by bioactivity-directed fractionation as part of a search for anticancer leads from filamentous fungi. Two known related compounds, acremonidin A (4) and acremonidin C (3) were also isolated, as was a known benzophenone, moniliphenone (1). The structures of these isolates were determined via extensive use of spectroscopic and spectrometric tools in conjunction with comparisons to the literature. All compounds (1–5) were evaluated against a suite of biological assays, including those for cytotoxicity, inhibition of the 20S proteasome, mitochondria transmembrane potential, and NF-κB.
acremonidin; anthraquinone; cytotoxicity; fungus; moniliphenone; 20S proteasome; xanthone
As part of our ongoing investigation of filamentous fungi for anticancer leads, an active fungal extract was identified from the Mycosynthetix library (MSX 63935; related to Phoma sp.). The initial extract exhibited cytotoxic activity against the H460 (human non-small cell lung carcinoma) and SF268 (human astrocytoma) cell lines and was selected for further study. Bioactivity-directed fractionation yielded resorcylic acid lactones (RALs) 1 (a new natural product) and 3 (a new compound) and the known RALs zeaenol (2), 5E-7-oxozeaenol (4), 5Z-7-oxozeaenol (5) and LL-Z1640-1 (6). Reduction of 5E-7-oxozeaenol (4) with sodium borohydride produced 3, which allowed assignment of the absolute configuration of 3. Other known resorcylic acid lactones (7–12) were purchased and assayed in parallel for cytotoxicity with isolated 1–6 to investigate structure-activity relationships in the series. Moreover, the isolated compounds (1–6) were examined for activity in a suite of biological assays, including antibacterial, mitochondria transmembrane potential, and NF-κB. In the latter assay, compounds 1 and 5 displayed sub-micromolar activities that were on par with the positive control, and as such, these compounds may serve as a lead scaffold for future medicinal chemistry studies.
Heat stress commonly leads to inhibition of photosynthesis in higher plants. The transcriptional induction of heat stress-responsive genes represents the first line of inducible defense against imbalances in cellular homeostasis. Although heat stress transcription factor HsfA2 and its downstream target genes are well studied, the regulatory mechanisms by which HsfA2 is activated in response to heat stress remain elusive. Here, we show that chloroplast ribosomal protein S1 (RPS1) is a heat-responsive protein and functions in protein biosynthesis in chloroplast. Knockdown of RPS1 expression in the rps1 mutant nearly eliminates the heat stress-activated expression of HsfA2 and its target genes, leading to a considerable loss of heat tolerance. We further confirm the relationship existed between the downregulation of RPS1 expression and the loss of heat tolerance by generating RNA interference-transgenic lines of RPS1. Consistent with the notion that the inhibited activation of HsfA2 in response to heat stress in the rps1 mutant causes heat-susceptibility, we further demonstrate that overexpression of HsfA2 with a viral promoter leads to constitutive expressions of its target genes in the rps1 mutant, which is sufficient to reestablish lost heat tolerance and recovers heat-susceptible thylakoid stability to wild-type levels. Our findings reveal a heat-responsive retrograde pathway in which chloroplast translation capacity is a critical factor in heat-responsive activation of HsfA2 and its target genes required for cellular homeostasis under heat stress. Thus, RPS1 is an essential yet previously unknown determinant involved in retrograde activation of heat stress responses in higher plants.
As a consequence of global warming, increasing temperature is a serious threat to crop production worldwide and may influence the objectives of breeding programs. As a universal cellular response to a shift up in temperature, the heat stress response represents the first line of inducible defense against imbalances in cellular homeostasis in the prokaryotic and eukaryotic kingdoms. Given that components of the photosynthetic apparatus housed in the chloroplast are the primary susceptible targets of thermal damage in plants, the chloroplasts were proposed as sensors to a shift up in temperature. However, the mechanism by which chloroplasts regulate the expression of nuclear heat stress–responsive gene expression according to the functional state of chloroplasts under heat stress remains unknown. In this study, we have identified chloroplast ribosomal protein S1 (RPS1) as a heat-responsive protein through proteomic screening of heat-responsive proteins. We have established a previously unrecognized molecular connection between the downregulation of RPS1 expression in chloroplast and the activation of HsfA2-dependent heat-responsive genes in nucleus, which is required for heat tolerance in higher plants. Our data provide new insights into the mechanisms whereby plant cells modulate nuclear gene expression to keep accordance with the current status of chloroplasts in response to heat stress.
The aim of this research was to increase the oral bioavailability of daidzein by the formulations of poly(lactic-co-glycolic) acid (PLGA) nanoparticles loaded with daidzein. Amongst the various traditional and novel techniques of preparing daidzein-loaded PLGA nanoparticles, daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were selected. The average drug entrapment efficiency, particle size, and zeta potential of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were 81.9% ± 5%, 309.2 ± 14.0 nm, −32.14 ± 2.53 mV and 83.2% ± 7.2%, 323.2 ± 4.8 nm, −18.73 ± 1.68 mV, respectively. The morphological characterization of nanoparticles was observed with scanning electron microscopy by stereological method and the physicochemical state of nanoparticles was valued by differential scanning calorimetry. The in vitro drug-release profile of both nanoparticle formulations fitted the Weibull dynamic equation. Pharmacokinetic studies demonstrated that after oral administration of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles to rats at a dose of 10 mg/kg, relative bioavailability was enhanced about 5.57- and 8.85-fold, respectively, compared to daidzein suspension as control. These results describe an effective strategy for oral delivery of daidzein-loaded PLGA nanoparticles and might provide a fresh approach to enhancing the bioavailability of drugs with poor lipophilic and poor hydrophilic properties.
daidzein; phospholipid complexes; cyclodextrin inclusion complexes; PLGA; nanoparticles
Intravascular large B-cell lymphoma (IVLBCL) is a rare, aggressive and often fatal non-Hodgkin lymphoma characterized by preferential growth of malignant B-cells within the lumina of small vessels. Rituximab plus anthracy-cline-based chemotherapy is the current standard regimen for IVLBCL, however it has minimal efficacy in relapsed or refractory diseases. Recent clinical trials have shown a significant anti-lymphoma activity of mammalian target of rapamycin (mTOR) inhibitors in relapsed and refractory diffuse large B-cell lymphoma (DLBCL); however, the activation status of the mTOR pathway and the therapeutic potential of mTOR inhibitors in IVLBCL have not yet been studied. Here we described the clinicopathological features of 3 cases of IVLBCL diagnosed at our institutions, and evaluated the activation status of the mTOR signaling in these tumors. Our results showed that the mTOR complex 2 pathway was selectively upregulated in IVLBCL, as evidenced by a predominant nuclear localization of the activated form of mTOR (p-mTOR at Ser2448) with concomitant overexpression of nuclear p-Akt (Ser473) and vascular endothelial growth factor (VEGF)-A in the lymphoma cells. These data suggest that overactivation of mTOR pathway may play a role in lymphomagenesis of IVLBCL and mTORC2 inhibitors may be beneficial in treating IVLBCL.
Intravascular large B-cell lymphoma; mTOR; Akt; VEGF
Material collected from a parkway in the city of Chicago afforded the isolation of a Nostoc species (UIC 10022A). The extract of this strain displayed significant inhibition of the 20S proteasome as well as antiproliferative activity against HT29, MCF7, NCI-H460, and SF268 cancer cell lines. A standardized dereplication protocol allowed for the rapid identification of three known (11-13) and nine new (1-9) chlorinated cylindrocyclophanes from less than 100 mg of organic extract. Scale-up isolation of 1-9 and 11-13 from a larger extract was guided by LC-UV-MS data. In addition, KBr enrichment of the culture media afforded the isolation of a brominated cylindrocyclophane (10). Biological evaluation of 1-5, 9, and 10-13 revealed a large range of activity against the 20S proteasome and allowed the determination of preliminary structure-activity relationships (SAR) of the cylindrocyclophane pharmacophore.
Phytophthora sojae causes soybean root and stem rot, resulting in an annual loss of 1-2 billion US dollars in soybean production worldwide. A proteomic technique was used to determine the effects on soybean hypocotyls of infection with P. sojae.
In the present study, 46 differentially expressed proteins were identified in soybean hypocotyls infected with P. sojae, using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization tandem time of flight (MALDI-TOF/TOF). The expression levels of 26 proteins were significantly affected at various time points in the tolerant soybean line, Yudou25, (12 up-regulated and 14 down-regulated). In contrast, in the sensitive soybean line, NG6255, only 20 proteins were significantly affected (11 up-regulated and 9 down-regulated). Among these proteins, 26% were related to energy regulation, 15% to protein destination and storage, 11% to defense against disease, 11% to metabolism, 9% to protein synthesis, 4% to secondary metabolism, and 24% were of unknown function.
Our study provides important information on the use of proteomic methods for studying protein regulation during plant-oomycete interactions.
The aim of this study was to develop new systems for transdermal delivery of paeonol, in particular microemulsion gel and cubic gel formulations.
Various microemulsion vehicles were prepared using isopropyl myristate as an oil phase, polyoxyethylated castor oil (Cremophor® EL) as a surfactant, and polyethylene glycol 400 as a cosurfactant. In the optimum microemulsion gel formulation, carbomer 940 was selected as the gel matrix, and consisted of 1% paeonol, 4% isopropyl myristate, 28% Cremophor EL/polyethylene glycol 400 (1:1), and 67% water. The cubic gel was prepared containing 3% paeonol, 30% water, and 67% glyceryl monooleate.
A skin permeability test using excised rat skins indicated that both the cubic gel and microemulsion gel formulations had higher permeability than did the paeonol solution. An in vivo pharmacokinetic study done in rats showed that the relative bioavailability of the cubic gel and microemulsion gel was enhanced by about 1.51-fold and 1.28-fold, respectively, compared with orally administered paeonol suspension.
Both the cubic gel and microemulsion gel formulations are promising delivery systems to enhance the skin permeability of paeonol, in particular the cubic gel.
microemulsion gel; cubic gel; transdermal delivery; paeonol