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81.
Many animals employ sex pheromones to find mating partners during their reproductive seasons. However, most sex pheromones of vertebrates remain to be identified. Over the past 20 years, steroids and prostaglandins have been identified as sex pheromones in several fishes. These pheromones are broadly termed "hormonal pheromones" because they or their precursors act as hormones in these fishes. Hitherto, no other type of sex pheromone has been unambiguously identified in teleost fish. Here we report the identification of a "nonhormonal pheromone" in teleost fish. The urine of the reproductively mature female masu salmon (Oncorhynchus masou) contains a male-attracting pheromone. Bioassay-guided fractionation yielded an active compound that was identical to L-kynurenine in spectral and chromatographic properties. L-Kynurenine is a major metabolite of L-tryptophan in vertebrates. This pheromone elicits a male-specific behavior at even picomolar concentrations; its electrophysiological threshold is 10(-14) M. L-Kynurenine is a reasonable substance for female masu salmon to advertise their readiness for mating.  相似文献   
82.
83.
Poly(4-hydroxycinnamic acid) (P4HCA), poly(3-hydroxycinnamic acid) (P3HCA), poly(3-methoxy-4-hydroxycinnamic acid) (PMHCA) and poly(3,4-dihydroxycinnamic acid) (PDHCA) were synthesized by the thermal poly-condensation of the corresponding monomers, which are lignin precursors, coumaric acid derivatives consisting of cinnamoyl groups and different position and number of OH groups. The solubility of the homo-polymers in organic solvents decreased in the order of P3HCA > PDHCA > P4HCA > PMHCA. The wide angle X-ray diffraction (WAXD) results indicated that P4HCA or PMHCA with p-OH group had higher crystallinity, in contrast to P3HCA or PDHCA with m-OH group which had lower crystallinity. Crossed-polarizing microscopy suggested that P4HCA had the nematic liquid crystal properties at 220 degrees C and PDHCA showed birefringence properties at 200 degrees C. In cell-adhesion tests, PDHCA showed the highest cell adhesion (ca. 70%), whereas P3HCA, P4HCA and PMHCA had 50, 18 and 10% cell adhesion, respectively. The coumaric acid derivative homo-polymers can be useful as cell adhesion controllable thermotropic polymers for biomedical and environmental fields.  相似文献   
84.
Hyperbranched copolymers with different degrees of branching (DBs), poly(3,4‐dihydroxycinnamic acid)‐co‐poly(4‐hydroxycinnamic acid) (PCA), were prepared by polycondensation. Amphiphilic PCA–DTT copolymers were prepared by grafting dithiothreitiol (DTT) into PCA by the Michael addition. PCA–DTT nanoparticles were self‐assembled by additional water into a DMSO solution of PCA–DTT. The diameter and photoresponsivity of the PCA–DTT nanoparticles were influenced by the DB, and they increased with increasing the DB. Bovine serum albumin (BSA) as a model protein was successfully encapsulated into the PCA–DTT nanoparticles, and the release behavior of BSA was affected by the DB in PBS. These biodegradable and photoresponsive nanoparticles would be useful as functional carriers for drug delivery systems.  相似文献   
85.
ART-123 is a recombinant soluble human thrombomodulin (hTM) with potent anticoagulant activity, and is available for developing antithrombogenic surfaces by immobilization. We focused on improving blood compatibility on the dialyzer surface by the physical adsorption of ART-123 as a safe yet simple method without using chemical reagents. The physical adsorption mechanism and anticoagulant activities of adsorbed hTM on the surface of a polysulfone (PSF) membrane containing polyvinylpyrrolidone (PVP) as a model dialyzer were investigated in detail. The PVP content of the PSF-PVP films was saturated at 20 wt% after immersion in Tris-HCl buffer, even with the addition of over 20 wt% PVP. The surface morphology of the PSF-PVP films was strongly influenced by the PVP content, because PVP covered the outermost surface of the PSF-PVP films. The adsorption speed of hTM slowed dramatically with increasing PVP content up to 10 wt%, but the maximum adsorption amount of hTM onto the PSF-PVP film surface was almost the same, regardless of the PVP content. The PSF-PVP film with the physically adsorbed hTM showed higher protein C activity as compared to the PSF film, it showed excellent blood compatibility due to the protein C activity and the inhibition properties of platelet adhesion. The physical adsorption of hTM can be useful as a safe yet simple method to improve the blood compatibility of a dialyzer surface.  相似文献   
86.
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive human malignancy in which the transforming growth factor beta (TGF-β) signal transducer, Smad4, is commonly mutated or deleted. BxPC3 human pancreatic cancer cells exhibit a homozygous deletion of the Smad4 gene, yet are growth inhibited by TGF-β1. In the present study, we sought to determine whether reintroduction of Smad4 into BxPC3 cells alters their behavior in vitro and in vivo. Sham transfected and Smad4 expressing BxPC3 cells exhibited similar responses to TGF-β1 with respect to p21 upregulation, hypophosphorylation of the RB protein, Smad2 phosphorylation, and Smad2/3 nuclear translocation. TGF-β1 did not alter p27 expression, and silencing of p21 with an appropriate siRNA markedly attenuated TGF-β1-mediated growth inhibition. Nonetheless, the presence of Smad4 was associated in vitro with a more prolonged doubling time, enhanced sensitivity to the growth inhibitory actions of exogenous TGF-β1, and a more flattened cellular morphology. In vivo, Smad4 expression resulted in delayed tumor growth and decreased cellular proliferation, without effects on either apoptosis or angiogenesis. These findings indicate that, in spite of the absence of Smad4, growth inhibition in BxPC3 cells by TGF-β1 is dependent on p21 upregulation and maintenance of RB in a hypophosphorylated, active state. Moreover, the presence of a functional Smad4 attenuates the capacity of BxPC3 cells to proliferate in vivo. However, this effect is transient, indicating that Smad4 growth inhibitory actions are circumvented in the later stages of pancreatic tumorigenicity.  相似文献   
87.
We report a case of pycnodysostosis and review 54 cases of this syndrome in the Japanese literature, with special emphasis on oral and maxillofacial findings. Common findings were as follows: hypoplasia of maxilla and mandible, hypopneumatization of the maxillary sinuses, loss of mandibular angle, a grooved palate, and malpositioned teeth.  相似文献   
88.
We compared the ocular hypotensive effect for 24 hours and the tolerability of latanoprost stored at 4 degrees C and 30 degrees C. Seventeen healthy volunteers were included in this crossover trial. Latanoprost 0.005% (Xalatan) was stored at 4 degrees C or 30 degrees C for 4 weeks in the dark. The subjects enrolled to the study were randomly assigned to receive either latanoprost stored at 4 degrees C or that stored at 30 degrees C. The eye drop was applied to the right eye of each subject for 3 days. The left eye served as a control without administration. Slit-lamp biomicroscopy and circadian intra ocular pressure (IOP) curve was performed at Day 3, every 3 hours from 6 pm. This procedure was repeated 7 days after changing the drug from 4 degrees C to 30 degrees C or vice versa, and application to the left eye for 3 days. Eyes treated with latanoprost, stored both at 4 degrees C and 30 degrees C, achieved statistically significantly lower mean IOPs than untreated eyes at all time points, except at 21 hours treated by the drug stored at 30 degrees C. We subtracted the IOP of eyes receiving latanoprost from the IOP of untreated eyes for each time point to evaluate the efficacy of the eye drops (delta IOP). There were no statistically significant differences between the delta IOPs with the drug stored at 4 degrees C and 30 degrees C. During the study, no subject developed a serious adverse event. These results suggest that latanoprost stored at 30 degrees C for 4 weeks after opening the bottle remains as effective and safe as latanoprost stored under cold conditions.  相似文献   
89.

Background

The aim of this multicenter, open-label, randomized phase II trial was to evaluate the efficacy of a dose-dense capecitabine and oxaliplatin (XELOX) regimen in patients with metastatic colorectal cancer (mCRC) for whom reintroduction of oxaliplatin had been planned as a third- or later-line regimen.

Methods

The patients with mCRC who had received prior chemotherapy including oxaliplatin and were scheduled for reintroduction of oxaliplatin were randomized to capecitabine (1,000 mg/m2) twice daily on days 1–14 and oxaliplatin (130 mg/m2) on day 1 every 21 days (Q3W group) or capecitabine (2,000 mg/m2) twice daily on days 1–7 and oxaliplatin (85 mg/m2) on day 1 every 14 days (Q2W group). The primary endpoint was the time-to-treatment failure (TTF). Other endpoints included overall survival (OS), progression-free survival (PFS) and other adverse events (AEs).

Results

A total of 46 patients were enrolled in the trial—22 patients were randomly assigned to the Q3W group and 23 to the Q2W group. The median TTF was 3.4 months in both groups (hazard ratio [HR] 1.053; p = 0.880). The median PFS and OS were 3.3 and 9.2 months in the Q2W group and 4.3 and 12.1 months in the Q3W group, respectively (HR 1.15; p = 0.153 and 0.672; p = 0.836). The most common grade 3?4 AEs in the Q3W and Q2W groups were fatigue (27.3 vs 21.7), neuropathy (9.1 vs 0 %) and diarrhea (9.1 vs 0 %), respectively.

Conclusion

There was no significant inter-group difference in any of the efficacy and safety endpoints, including TTF, OS, RFS and AEs. The results of this clinical trial were convincingly negative.
  相似文献   
90.
Monoclonal antibodies against epidermal growth factor receptor(EGFR) are used in the treatment of advanced colorectal cancer. However, these agents can induce severe dermatological side effects that discourage their administration in patients with chronic dermatological disease. EGFR plays a key role in normal skin development and immunological function, and is expressed in various tissues and organs, although contrarily, it is overexpressed in psoriasis-related skin lesions. Thus, discussion is ongoing regarding the putative pathological role and therapeutic potential of this protein. We herein report on a patient with advanced colon cancer and concomitant long-standing psoriasis vulgaris who received antiEGFR antibody monotherapy as a third-line treatment for metastatic disease. One week after the initiation of treatment, the patient’s skin lesions dramatically subsided and the improvement was sustained during therapy. Based on this case, we propose that anti-EGFR antibody therapy is not necessarily contraindicated in patients with psoriasis vulgaris. Moreover, the findings reaffirmed that EGFR is an important molecule in the pathology of psoriasis.  相似文献   
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