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991.
Detecting rare circulating tumor cells (CTCs) in the bloodstream is extremely challenging. We had previously developed a novel polymeric microfluidic device, “CTC‐chip,” for capturing CTCs and have shown high capture efficiency in lung cancer cell lines by conjugating Abs against epithelial cell adhesion molecules (EpCAM). This study aimed to optimize the EpCAM‐chip and clarify the prognostic impact of CTCs in lung cancer patients. Of 123 patients with pathologically proven lung cancer, both progression‐free survival (P = .037) and cancer‐specific survival (= .0041) were predominantly poor when CTCs were detected before treatment. After classification into surgical and chemotherapy groups, progression‐free survival was worse in CTC‐positive patients in both groups (surgery, = .115; chemotherapy, = .012), indicating that the detection of baseline CTCs is a risk factor for recurrence and progression. Furthermore, we recovered captured CTCs using micromanipulators and undertook mutation analysis using PCR. Thus, the EpCAM‐chip is a highly sensitive system for detecting CTCs that contributes to the prediction of recurrence and progression and enables genetic analysis of captured CTCs, which could open new diagnostic, therapeutic, and prognostic options for lung cancer patients.  相似文献   
992.
993.
The sugar chains covalently modifying proteins and lipids are recognized by a variety of proteins, thereby mediating a broad range of physiological and pathological events on cell surfaces as well as in cells. Hence, these carbohydrate-protein interaction systems could be potential therapeutic targets for various diseases, including viral infections, autoimmune diseases and neurodegenerative disorders. Cumulative crystallographic data of lectins complexed with their cognate carbohydrate ligands have elucidated the sugar recognition modes of these proteins, offering a structural basis for the design of drugs targeting carbohydrate-lectin interaction systems. In particular, structural and functional studies of animal L-type lectins, which possess a carbohydrate recognition domain with a structural resemblance to that of leguminous lectins such as concanavalin A, have demonstrated the molecular mechanisms underlying their distinct roles in sorting and trafficking of glycoproteins in cells, exemplifying the structure-based engineering that manipulates the sugar-binding properties of lectins. Furthermore, structural basis has been provided for the functional interplay between the L-type lectin ERGIC-53 and the EF-hand Ca2?-binding protein MCFD2 in the intracellular transport of the coagulation factors V and VIII. This article also deals with pathological carbohydrate-protein interactions involving ganglioside clusters on cell surfaces, particularly focusing on the interaction between amyloid β (Aβ) and GM1 ganglioside. This interaction triggers conformational transition and consequent aggregation of Aβ, and therefore, is considered to be a key step in Alzheimer's disease. The recently reported structural information of the Aβ-GM1 interaction is presented, underscoring the significance of assemblages of glycoconjugates as therapeutic targets.  相似文献   
994.
There is evidence that radiation exposure is a causative factor of myelodysplastic syndromes (MDS). However, little is known about whether radiation exposure is also a prognostic factor of MDS. We investigated the impact of radiation exposure on the prognosis of MDS in Nagasaki atomic bomb survivors using the International Prognostic Scoring System (IPSS) and the revised version (IPSS‐R). Subjects were 140 patients with primary MDS diagnosed between 1985 and 2011 and evaluable for IPSS, IPSS‐R, and exposure distance. Of those, 31 were exposed at <1.5 km, 35 at 1.5–2.99 km, and 74 at ≥3.0 km. By the end of March 2014, 47 patients (34%) progressed to overt leukemia and 106 (75.7%) died. By comparing with patients exposed at ≥3.0 km, those exposed at <1.5 km had significantly higher frequencies of abnormal chromosome (P = 0.02), intermediate/poor IPSS, and intermediate/poor/very poor IPSS‐R cytogenetic category (P = 0.0001, and P < 0.0001, respectively). As with de novo MDS, multivariate Cox regression analyses revealed that cytogenetic abnormalities, IPSS karyotype, and IPSS‐R cytogenetics were significantly associated with poor survival, and cumulative incidence of leukemic transformation in MDS among atomic bomb survivors, but exposure distance was not associated with any poor outcomes. These suggest that exposure to the greater dose of atomic bomb radiation is associated with developing poor cytogenetic abnormalities in MDS, which might consequently lead to overt leukemia among atomic bomb survivors.  相似文献   
995.
Horie S  Watanabe Y  Ono M  Mori S  Kodama T 《Cancer science》2011,102(11):2082-2089
The antitumor effects of tumor necrosis factor (TNF-α) were evaluated following transfection of TNF-α plasmid DNA into solid mouse tumors using the nanobubbles (NBs) and ultrasound (US) gene delivery system. Murine breast carcinoma (EMT6) cells expressing luciferase (1 × 10(6) cells) were injected intradermally into the flanks of 6-7-week-old male SCID mice on day 0. Ten microliters of TNF-α (5 μg/μL) or TNF-α mock plasmid DNA (5 μg/μL) with/without NBs (15 μL) and saline was injected intratumorally in a total volume of 30 μL, and tumors were exposed to US (frequency, 1 MHz; intensity, 3.0 W/cm(2); duty cycle, 20%; number of pulses, 200; and exposure time, 60 s) on days 2, 4, 7, and 9. Changes in tumor size were measured with an in vivo bioluminescent imaging system and a mechanical caliper. Changes in tumor vessel area were quantified using contrast-enhanced US imaging with Sonazoid and a high frequency US imaging system (40 MHz) and immunohistochemistry (CD31). At the mRNA level, expression of TNF-α, caspase-3, and p53 were quantified using real-time quantitative RT-PCR. At the protein level, expression of caspase-3 and p53 were confirmed by immunohistochemistry. We show that repeated TNF-α gene delivery using NBs and US can lead to the local production of TNF-α. This results in antitumor effects, including activation of p53-dependent apoptosis, decrease in tumor vessel density, and suppression of tumor size. In this study, we showed the effectiveness of using NBs and US for TNF-α gene delivery into tumor cells.  相似文献   
996.
The main purpose of the present study was to develop a novel formulation of St. John's Wort (SJW) extract with the aim of improving its pharmacokinetics and anti-nociceptive effect. Several formulations of SJW were prepared, including cyclodextrin inclusion (SJW-CD), solid dispersion (SJW-SD), dry-emulsion (SJW-DE), and nano-emulsion (SJW-NE). Physicochemical properties of SJW formulations were characterized with a focus on the morphology, dissolution behavior, colloidal properties, and dispersion stability in water. Although all the SJW formulations and SJW extract itself exhibited fine dissolution behavior in water, SJW extract and most formulations tended to cream, aggregate, or flocculate after dispersion in distilled water. In contrast, there were no significant changes in appearance and particle size of the SJW-NE for at least a few weeks, suggesting that SJW-NE was the most stable form as a carrier of SJW in the present study. After oral administration of the SJW-NE formulation (5.2 mg hyperforin/kg) in mice, higher hyperforin exposure in plasma (1188 ± 41 nM·h) and the brain (52.9 ± 1.6 pmol/g tissue·h) was observed with 2.8- and 1.3-fold increases of the area under the concentration curve from 0 to 6 hours (AUC(0-6)) compared to those of the SJW extract (417 ± 41 nM·h in plasma and 41.6 ± 1.5 pmol/g tissue·h in the brain). In the formalin test for scoring properties of the first and second phases of the pain response in mice, single oral administration of SJW-NE significantly reduced the nociceptive response compared with SJW extract. From these findings, the NE approach might be efficacious in improving the oral bioavailability and anti-nociceptive effect of SJW extract.  相似文献   
997.
Human T-cell leukemia virus type 1 (HTLV-1) is the causative retrovirus of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1-specific T-cell responses elicit antitumor and antiviral effects in experimental models, and are considered to be one of the most important determinants of the disease manifestation, since they are activated in HAM/TSP but not in ATL patients. The combination of low T-cell responses and elevated HTLV-1 proviral loads are features of ATL, and are also observed in a subpopulation of HTLV-1 carriers at the asymptomatic stage, suggesting that these features may be underlying risk factors. These risks may potentially be reduced by vaccination to activate HTLV-1-specific T-cell responses. HAM/TSP and ATL patients also differ in their levels of HTLV-1 mRNA expression, which are generally low in vivo but slightly higher in HAM/TSP patients. Our recent study indicated that viral expression in HTLV-1-infected T-cells is suppressed by stromal cells in culture through type-I IFNs. The suppression was reversible after isolation from the stromal cells, mimicking a long-standing puzzling phenomenon in HTLV-1 infection where the viral expression is very low in vivo and rapidly induced in vitro. Collectively, HTLV-1 is controlled by both acquired and innate immunity in vivo: HTLV-1-specific T-cells survey infected cells, and IFNs suppress viral expression. Both effects would contribute to a reduction in viral pathogenesis, although they may potentially influence or conflict with one another. The presence of double control systems for HTLV-1 infection provides a new concept for understanding the pathogenesis of HTLV-1-mediated malignant and inflammatory diseases.  相似文献   
998.

Purpose

The aim of this study was to determine whether TP53 mutation status (MS) can predict response of breast cancer to paclitaxel followed by 5-FU/epirubicin/cyclophosphamide (P-FEC). TP53 gene expression signature (GES) was also examined for its predictive capability of response to P-FEC since TP53 GES provides a more accurate measure of the functional configuration of TP53.

Methods

Tumor samples were obtained from 72 primary breast cancer patients (stage II/III) before neoadjuvant chemotherapy (P-FEC) and analyzed for identification of TP53 MS (genomic sequencing), TP53 GES (DNA microarray), and p53 protein expression (immunohistochemistry).

Results

Of 72 breast tumors, 16 were TP53 mutant-type (TP53 mt) and 56 were wild-type (TP53 wt). 29 tumors (40%) were positive for p53 protein by immunohistochemistry. DNA microarray analysis showed that 27 were TP53 mt-like tumors and 45 were TP53 wt-like tumors, depending on the expression signature of the TP53-related 31-genes. There was no statistically significant difference in pathological complete response (pCR) rates between TP53 mt and wt tumors (19% vs 23%) and between p53 positive and negative tumors (24% vs 21%) but TP53 mt-like tumors showed a significantly (= 0.019) higher pCR rate (37%) than TP53 wt-like tumors (13%) (Hazard ratio, 3.82; 95% C.I., 1.20–12.21).

Conclusions

TP53 GES, but not TP53 MS and p53 protein expression, is predictive of response to neoadjuvant P-FEC, suggesting that TP53 GES more correctly reflects the functionality of TP53.  相似文献   
999.
In the present study, we investigated whether the pharmacy services in our psychiatric hospital helped to improve the attitude of psychiatric patients to drugs. The subjects were 168 patients who received advice on medication at the hospital between August 2008 and December 2009. We found that anxiety about medication in 76% of these patients was relieved by the provision of clinical pharmacy services. This can be attributed to patients gaining an understanding of the importance of taking medication at a particular time, drug types, drug efficacy and drug-induced adverse events. Patient drug adherence scores using the 10-item version of the Drug Attitude Inventory (DAI-10) were significantly improved after pharmacy services were provided, indicating an improvement in drug adherence. There was a significant positive correlation between the DAI-10 score and understanding of the necessity for medication, but no correlation between the DAI-10 score and the amount of drug administered or number of doses taken per day. These results suggest that the clinical pharmacy services improve understanding of the importance of medication timing, drug type, drug efficacy and drug-induced adverse events, and also relieve medication anxiety, enhance understanding of the necessity of taking medication and improve patient attitude to a drug. We intend to further take comprehensive measures including educational, behavioral and emotional intervention.  相似文献   
1000.
The mechanism of complexation between risperidone (RISP) and (-)-epigallocatechin gallate (EGCg) was clarified by 1H-NMR and molecular modeling studies. RISP and EGCg formed an insoluble complex with a 1 : 1 stoichiometry in aqueous solution. In the 1H-NMR spectra of RISP in DMSO-d?, the chemical shifts of protons neighboring the N atom on the piperizine ring clearly moved downfield upon formation of the complex. In the molecular modeling study, the 1H-chemical shifts for nine optimized structures of the complex were calculated to compare them with those of the experimental results. Only one conformer with the second minimum energy for the complex supported the downfield shifts of RISP protons. It was found from the structure of the complex that the two hydrogen bonds between hydroxyl groups of the galloyl ring in EGCg and N atoms in RISP, one of which was on the piperizine ring, were formed to stabilize the complex.  相似文献   
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