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        검색결과 564

        341.
        2012.03 구독 인증기관 무료, 개인회원 유료
        This study was conducted in order to evaluate the alleviating effects of Phellodendrin cortex water extract (PCWE) on skin aging in hairless mice via observation of morphogical and histological changes. Skin aging was induced by UVB irradiation and application of squalene monohydroperoxide (Sq-OOH) to the back skin of hairless mice for six weeks. And, at the same time, saline (C), jojoba oil (VC), PCWE (E), and 0.01% retinoic acid diluted with polyethylene glycol (PC) were applied topically twice per day, six days per week, for a period of six weeks. Improved wrinkle formation in a pattern of shallow furrows and thin and narrow crests was observed in the retinoic acid and PCWE application groups, compared to the C group. On the morphologic analysis for skin wrinkles, the E group showed lower levels in skin roughness, maximum roughness, average roughness, smoothness depth, and arithmetic average roughness by 13.1, 17.2, 18.4, 15.4, and 16.1%, respectively, compared with the C group, indicating that PCWE inhibited potential formation of wrinkles in the skin. In the C group, structures of lipid lamellae and collagen fibers were broken or deformed with an irregular arrangement. Application of retinoic acid and PCWE protected against the deformity of lipid lamellae and collagen fibers. Elastic fibers in dermis of the C group also showed severe transformation; however, applications of retinoic acid and PCWE resulted in a significant decrease in the number of denatured elastic fibers. Therefore, PCWE could have an alleviating effect on skin aging induced by UVB irradiation and application of Sq-OOH.
        4,300원
        342.
        2012.03 구독 인증기관 무료, 개인회원 유료
        Malignant pleural effusion (MPE) and blood samples can be used as a practical source for detection of epidermal growth factor receptor (EGFR) mutations in patients with advanced non-small cell lung cancer. We compared EGFR mutation status of cell blocks, cell-free fluid of MPE, and plasma from patients with lung adenocarcinoma. We obtained paired samples of MPE and plasma from 14 pathologically-confirmed lung adenocarcinoma patients. Peptide nucleic acid (PNA)-mediated real-time polymerase chain reaction (RT-PCR) clamping was performed for determination of EGFR mutation status. EGFR mutations were detected in five (35.7%) cell blocks of MPE, which showed results identical to those of the corresponding cell-free fluid, whereas mutations were detected in the plasma of only two (40.0%) of the five patients. Of seven patients treated with EGFR tyrosine kinase inhibitors (TKIs), EGFR mutations were detected in cell blocks, cell-free fluid of MPE, and plasma for only one of the four patients who responded to EGFR TKIs, while mutations were detected only in cell blocks of MPE and cell-free fluid of the three remaining patients. Our results suggest that detection of EGFR mutations in cell-free pleural fluid from lung adenocarcinoma patients using highly sensitive methods may be feasible, but that analysis of free plasma may lead to undetected mutations and misdiagnosis.
        4,000원
        343.
        2012.03 구독 인증기관 무료, 개인회원 유료
        House dust mite (HDM) allergens have been associated with allergic diseases, such as asthma, allergic rhinitis, and atopic dermatitis. Various acaricidal agents have been suggested for control of house dust mites; however, their remains act as allergens even after death. Therefore, for avoidance of allergen, expelling the mites is a more effective policy than killing them. In this experiment, we compared the repellent effect of two essential oils (Matricaria chamomilla, Lavandula vera) against house dust mites, Dermatophagoids farinae and D. pteronyssinus in bed fabric. The essential oils were applied by direct contact method at various doses (0.1, 0.05, 0.025, 0.0125, and 0.00625 μl/cm2 and at various exposure times (30, 60, 120, 180, and 240 min). Results of this experiment suggest that the two oils have significant repellent activity. Camomile essential oil in 0.0125 μl/cm2 at 240 minutes had a repellent effect of 93.7% and lavender essential oil in 0.05 μl/cm2 at 180 minutes had a repellent effect of 88.9%. The results of this study showed that camomile essential oil has more potent repellent activity than lavender essential oil at a particular concentration.
        4,000원
        344.
        2012.03 구독 인증기관 무료, 개인회원 유료
        This study demonstrated that hyaluronic acid (HA) accelerated peripheral nerve regeneration after crush injury to the common peroneal nerve in an experimental rabbit model. Ten male New Zealand White rabbits, weighing 1.8 to 2.0 kg, were used in this study. After creating the nerve crush model in every right leg, rabbits were divided into two groups. Animals in group A received application of HA into the area surrounding the crushed nerve, and group B was the sham control. Electrophysiological assessment was performed every week. After 10 weeks, nerve histological examination, muscle weight and muscle histology were used to evaluate regeneration of the injured common peroneal nerve. No differences in electrophysiological assessment were observed between the two groups. In peripheral nerve histology, myelinated nerve fibers were observed more frequently and less connective tissue was observed in the crushed nerve of group A. Fewer muscle degenerative changes, such as fibrosis, atrophy, and centrally located myonuclei, were detected in group A than in group B. In conclusion, HA could become a potential neuroprotective agent for improvement of peripheral nerve regeneration after crush injury.
        4,000원
        345.
        2012.03 구독 인증기관 무료, 개인회원 유료
        Cytokines are known to function as regulatory molecules that can be produced by virtually every nucleated cell type in the body, including lymphocytes, monocytes/macrophages, epithelial cells, fibroblasts, and many others. Cytokines include lymphocyte-derived factors (lymphokines), monocyte-derived factors (monokines), hematopoietic factors (colony-stimulating factors), connective tissue/ growth factors, and chemotactic chemokines. Cytokines released in response to infection can affect tumor development in different ways. When exposed to infectious agents, cytokines are secreted by sentinel cells, such as macrophages and dendritic cells. These cytokines include interleukin 1 (IL-1) and tumor necrosis factor-α, as well as others, such as IL-6, IL-12, and IL-18. When released in sufficient quantities, these molecules can cause inflammation. Chronic inflammation is highly associated with tumor initiation, promotion, and progression. In this article, we review the roles and mechanisms of cytokines in tumor development.
        4,300원
        346.
        2011.12 구독 인증기관 무료, 개인회원 유료
        Pneumatosis cystoides intestinalis (PCI) is a rare condition characterized by multiple intramural pockets of gas filled cysts in the intestinal wall. PCI is usually found incidentally on an imaging study. Many different causes of PCI have been suggested, including mechanical, pulmonary, and bacterial causes. Treatment is usually conservative, including oxygen and antibiotic therapy. We report on two cases of PCI, without symptoms, in a 62-year-old male and a 72-year-old male. Computed tomography showed numerous, small, round, and air densities on the sigmoid colon. Colonoscopy showed numerous, variable-sized, sessile polypoid, balloon-like distended, and protruding subepithelial masses covered with normal colonic mucosa on the sigmoid colon. We observed that when the cyst was stuck with a needle, the size of the cyst was reduced and showed a flat termination. Therefore, we made a diagnosis of PCI and report on the case with references.
        4,000원
        347.
        2011.12 구독 인증기관 무료, 개인회원 유료
        Endocrine disrupting chemicals (EDCs) have detrimental effects on human health. Among these EDCs, bisphenol A (BPA) binds to estrogen receptors (ERs) to stimulate estrogen-mediated responses. BPA is assumed to disrupt the reproductive and developmental system of humans. In addition, BPA has recently been suspected as a risk of carcinogenesis. Because BPA can cause abnormal estrogen-mediated response in the organism, exposure to BPA may stimulate growth of estrogen-dependent breast cancers in human. In breast cancer, cyclin E and cyclin-dependent kinase inhibitor p27 are important in G1/S phase transition during cell cycle progression. In this study, using an MTT assay, we investigated the effect of BPA on proliferation of MCF-7 breast cancer cells in vitro. In addition, we also analyzed the transcriptional levels of cyclin E and p27 following treatment with BPA using semi-quantitative RT-PCR. As a result, treatment with BPA resulted in significant induction of breast cancer cell growth, compared to a vehicle. BPA caused alterations of cyclin E and p27 mRNA expression. Expression of cyclin E was increased by BPA, while p27 was decreased at 24 h after treatment with BPA in MCF-7 breast cancer cells. Taken together, these collective results suggest that exposure to BPA induced breast cancer cell proliferation with deregulation of the cell cycle. A further study is required in order to determine the effects of BPA on the carcinogenic process in in vivo models.
        4,000원
        348.
        2011.12 구독 인증기관 무료, 개인회원 유료
        This study was conducted for evaluation of the alleviating effects of Phellodendrin cortex water extract (PCWE) on skin inflammation in hairless mice. Skin inflammation was induced by UVB irradiation and application of squalene monohydroperoxide (Sq-OOH) to the back skin of hairless mice for six weeks. At the same time, saline (C), jojoba oil (VC), PCWE (E), and 0.01% retinoic acid diluted with polyethylene glycol (PC) were applied topically twice per day, six days per week for a period of six weeks. The skin erythema index of the E group was lower than that of the C group. Epidermis and dermis of the C group were remarkably thickened, compared to the PC or E group. In the C group, infiltration of many inflammatory cells, including neutrophils and lymphocytes, was observed in dermis, and a large number of mast cells were observed in dermis and hypodermis; the degree of degranulation was remarkable. However, these phenomena were alleviated in the PC and E2 groups. The E group showed a lower activity in skin xanthine oxidase but a higher activity in skin superoxide dismutase, compared to the C group (P<0.05). The VC, PC, and E groups also showed a high activity of skin catalase by 25.3%, 58%, and 42%, respectively, compared to the C group. Taken together, these results indicate that PCWE could have an alleviating efficacy on skin inflammation induced by UVB irradiation and application of Sq-OOH in hairless mice.
        4,000원
        349.
        2011.12 구독 인증기관 무료, 개인회원 유료
        As a sensor of cellular energy status, AMP-activated protein kinase (AMPK) plays an important role in the pathophysiology of diabetes and its complications. Because AMPK is also expressed in podocytes, podocyte AMPK would be an important factor contributing to development of podocyte injury. We investigated the roles of AMPK in the pathological changes of podocyte synaptopodin induced by angiotensin II (Ang II), a major injury inducer. Mouse podocytes were incubated in media containing various concentrations of Ang II and AMPK-modulating agents, and the changes of synaptopodin were analyzed by confocal imaging and Western blotting. Ang II and compound C, an AMPK inhibitor, concentrated and re-localized synaptopodin from peripheral cytoplasm to the internal cytoplasm portion in podocytes. Ang II also reduced synaptopodin protein and mRNA, which were reversed by metformin and 5-aminoimidazole-4-carboxamide ribonucleoside. Losartan, an Ang II type 1 receptor antagonist, also recovered synaptopodin mRNA, which was suppressed by Ang II. We suggest that Ang II induces the relocation and suppression of podocyte synaptopodin by suppression of AMPK and via Ang II type 1 receptor, which would be an important mechanism in Ang II-induced podocyte phenotypical changes.
        4,000원
        350.
        2011.12 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to determine the effect of macrophages on growth of human colon cancer cells. The results showed that co-culture of colon cancer cells with macrophages inhibited the growth of colon cancer cells (HCT116 and SW620) depending on the number of macrophages, RAW 264.7 cells, and activated THP-1 cells accompanied by down regulation of pSTAT3 in cancer cells. We also found that expression and release of cancer cell growth inhibitory cytokines, IL-1 receptor antagonist (IL-1ra) and IL-10, was increased in macrophages. Blocking of the STAT3 pathway with specific inhibitor and siRNA of STAT3 abolished the growth of colon cancer cells and expression of IL-1ra and IL-10. In addition, neutralization of IL-1ra and IL-10 with antibodies resulted in reversal of macrophage-induced inhibition of cancer cell growth. These data showed that IL-1ra and IL-10 released from macrophages inhibit growth of colon cancer cells through inhibition of the STAT3 pathway.
        4,500원
        351.
        2011.12 구독 인증기관 무료, 개인회원 유료
        Antimicrobial peptides are widely found in living organisms and are known to play a critical role in innate immunity. Numerous antimicrobial peptides from diverse species appear to be effective against pathogenic microorganisms of bacteria, fungi, protozoa, and viruses. Because antibiotic resistance is a global health issue in the fight against pathogenic microorganisms, there has been an urgent need for development of new antibiotic substances. In the current study, we performed yeast two hybrid screening using Beclin1 bait in order to find new peptide antibiotics from a random peptide library. Two candidate peptides from the screening were expressed in a yeast secretory system of Pichia pastoris and tested for any antimicrobial activity against Staphylococcus aureus, MRSA, MRSA2242, MRSA2250, Lactobacillus casei, and Lactobacillus acidophilus. Disc clear zone assay and spectrophotometric analysis revealed that the two peptides exert a decent activity against the pathogenic bacteria, in contrast to minimal effect on the commensal Lactobacillus strains. Taken together, this study presents novel peptides with antibacterial activity against the pathogenic forms of Staphylococcus aureus and suggests the possibility that these peptides, upon further characterization, may be developed as clinically useful antibiotics.
        4,000원
        352.
        2011.09 구독 인증기관 무료, 개인회원 유료
        Macrophages can recognize antigens and microorganisms, and then initiate an appropriate defense. However, there has been a lack of comprehensive information regarding the genes that are modulated by commensal yeasts, including Saccharomyces cerevisiae or Saccharomyces exiguus. In addition, it is not clear to what extent the beneficial yeasts modulate the immune response against microbes and/or microbial toxins. Using DNA microarray, which contains approximately 25,000 genes, we studied interactions between host cells and yeast/bacterial toxin (LPS) by analyzing the transcriptional response of macrophages stimulated by Saccharomyces exiguus and/or Lipopolysaccharides. Thirty three genes were identified to be modulated by more than two folds between groups of macrophage cells. Pathway analysis provided insight into the mutual interactions. Of particular interest was the responses elicited by fungus in murine macrophage cells, including modulation of immunity/defense, cellular signal transduction, cell proliferation/differentiation, and transport. This finding indicates that the yeast induces immune response pathways as well as those associated with cell proliferation and transport. Among the 33 genes identified from the DNA microarray screening, eight genes were further checked by RT-PCR analysis using gene specific primers. Compared to those of negative control, sequential treatment with the yeast strain followed by LPS apparently induced expression of Tnfaip3, IL7R, and CD86, while it inhibited expression of Cxcl10 and CD83. In conclusion, this study identified the genes that are up-regulated by Saccharomyces exiguus. A further study is needed in order to determine whether these genes are modulated at the protein level, and also for their roles in control of immune responses.
        4,000원
        353.
        2011.09 구독 인증기관 무료, 개인회원 유료
        Immunotherapeutic approaches using agonist antibodies or fusion proteins of immunomodulatory molecules significantly inhibit tumor growth and boost cell-mediated immunity. We isolated mRNA from previously reported 1D4 hybridoma cells and amplified the variable regions of the heavy chain (VH) and light chain (VL) genes using reverse-transcriptase polymerase chain reaction. Using a linker, the amplified sequences for the heavy and light chains were each connected to the sequence for a single polypeptide chain that was designed to be expressed. VL and VH fragments were cloned into the pOptiVEC-TOPO vector containing the human CH2-CH3 fragment. Then, 293T cells were transfected with the 1D4 single-chain Fv-Fc (scFv-Fc) constructs. A549 cells were used for presentation of the 1D4 antigen. Flow cytometry was performed for analysis of the secreted 1D4 scFv-Fc constructs. The DNA sequence of 1D4 scFv-Fc was obtained. The 1D4 scFv-Fc constructs were expressed by the transfected 293T cells and secreted into the culture medium. The immunoreactivity of the secreted scFv-Fc construct was lower than that of the murine 1D4 antibody for A549 cells. A 1D4 scFv-Fc construct for immunotherapy was developed.
        4,000원
        354.
        2011.09 구독 인증기관 무료, 개인회원 유료
        In this study, a nanofibrous scaffold was obtained by co-electrospinning poly (3-hydroxybutyrate- co-3-hydroxyvalerate) (PHBV) and collagen in 2,2,2-trifluoroethanol at a ratio of 3/7. The fiber diameters were in the range of 250-600 nm. It was found that PHBV/Collagen (PHCP) nanofibrous scaffold showed greater proliferation than the PHBV nanofibrous scaffold induced by oxidant in NIH3T3 cells. Otherwise, in the early-stage wound-healing mouse model, wound closure was evaluated according to wound size reduction and histology of regenerated skin on the backs of mice. Each of the tissues removed on day 0, 3, 6, 9, 12, 15, and 18 was used for analysis of biochemical and pathological changes. None of the nanofiber-attached mice showed significant difference on the third day, however, from the third day until the ninth day, significantly faster healing was observed in PHCP-attached mice, compared to control wounds in epithelialization, wound contraction, and histopathological examinations. These results strongly support the beneficial effects of biomedical application of PHCP nanofiber in acceleration of the initial phase of wound healing through α-SM actin contraction.
        4,000원
        355.
        2011.09 구독 인증기관 무료, 개인회원 유료
        The effects of β-lapachone on gastric secretion were investigated. The pylorus of male Sprague-Dawley rats was ligated and intraduodenally injected with β-lapachone, and the volume, pH, free HCl, and total acidity of gastric fluid were measured 6 hours after the operation. Treatment with β-lapachone resulted in dose-dependent inhibition of gastric secretion Gastric fluid was reduced to 42.9% of control level by 100 mg/kg of β-lapachone, leading to an increase of pH to 6.70 from 1.85 in the control group. In parallel with the increase of pH, at this dosage, free HCl and total acidity decreased to 16.7% and 12.0%, respectively, of control levels. β-Lapachone exhibited ED50 values of 72, 46, and 47 mg/kg for inhibition of gastric volume, free HCl, and total acidity, respectively, implying a superior efficacy on gastric acid to volume. In comparison, pantoprazole (30 mg/kg) reduced the volume, free HCl and total acidity of gastric fluid to 53.0%, 26.0%, and 25.0%, respectively, of control levels, resulting in an increase in pH to 6.36. In the current study, it was confirmed that β-lapachone at an appropriate dose (100 mg/kg) exerted a higher inhibitory effect on gastric secretion than pantoprazole (30 mg/kg), a well-known proton-pump inhibitor. Therefore, it is suggested that β-lapachone could be a candidate compound for prevention or treatment of gastric ulcers induced by diverse psychological and physical stimuli.
        4,000원
        356.
        2011.09 구독 인증기관 무료, 개인회원 유료
        The current study was designed to investigate the effect of Red ginseng extract on development of colonic aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH) in male F344 rats. Five-week old animals received subcutaneous injections of DMH (30 mg/kg body weight) four times, for a period of two weeks in order to induce ACF. The animals were divided into groups fed a diet containing red ginseng extract at three different doses (0.5, 1.0, and 2.0%), respectively. Animals were evaluated for the total number of ACF and total aberrant crypts (AC) per colon detected from methylene blue-stained rat colon. ACF formation was observed in animals in the DMH-treated group. Four-time treatment with DMH induced mean 265.8±48.3 ACF/colon composed of a total of 608.8±110.9 aberrant crypts AC/colon. The numbers of ACF and AC induced by DMH were decreased to 204.4±29.3 and 464.7±70.3 by treatment with 0.5% red ginseng extract. In addition, the number of large ACF (≥4 AC/ACF) was suppressed from 39.9±10.6 ACF/colon in control to 28.5±5.3 ACF/colon in 0.5% red ginseng extract. These results suggested that red ginseng extract exerted a chemopreventive effect on DMH-induced colon cancer by inhibiting development of ACF and AC in F344 rats.
        4,000원
        357.
        2011.09 구독 인증기관 무료, 개인회원 유료
        As a sensor of cellular energy status, AMP-activated protein kinase (AMPK) is known to play an important role in the pathophysiology of diabetes and its complications. Because AMPK is also expressed in podocytes, it is possible that podocyte AMPK would be an important contributing factor in development of proteinuria. In recent years, despite intensified interest in AMPK in the kidney, studies on the role of AMPK in podocytes are limited. In this review, I will discuss the roles of AMPK in podocytes, which may be involved in development of podocyte dysfunction and proteinuria, and the possibility of AMPK-modulating drugs in prevention and treatment of podocytopathy.
        4,000원
        358.
        2011.06 구독 인증기관 무료, 개인회원 유료
        The current study was conducted in order to investigate promotional effects of herbal extracts on hair growth in an animal model of mice. There were four experimental groups, including distilled water (DW) as a negative control (NC), 3% minoxidil (MXD) as a positive control (PC), 50% ethanol (EtOH) as a vehicle control (VC), and herbal extract (HE) as the experimental treatment (E). The HE was extracted with ethanol from plants, including Gardenia, Mentha arvensis, Rosemary, and Lavender. Six-week-old C57BL/6 male mice were shaved with an electric clipper and the test materials were topically treated with 0.2 ml per mouse daily for three weeks. Photographic evaluation of hair re-growth was performed weekly during a period of three weeks. The number of mast cells was counted on the dorsal skin section of mice. The enzymes, alkaline phosphatase (ALP) and γ-glutamyl transpeptidase (γ-GT), were determined using a biochemical autoanalyzer. No clinical signs were observed in any of the experimental groups. As a result of photometric analysis, topical application of HE to dorsal skin for two weeks resulted in significantly faster acceleration of hair regrowth, compared with that of the NC or VC group (P<0.05). The PC and E groups showed a significant decrease in mast cell population, compared to the NC group. Activities of ALP and γ-GT were significantly increased in the PC and E groups, compared to the NC or VC group (P<0.05). Taken together, these results suggest that the herbal extract may have hair-growth promoting activity equal to that of MXD.
        4,000원
        359.
        2011.06 구독 인증기관 무료, 개인회원 유료
        Zinc oxide nanoparticles (nZnO) are used in a various range, including ceramic manufacture, photocatalysis, UV filters, and the food industry. However, little is known about the effects of micro- and nano-particles during mouse embryo organogenesis. To determine whether ZnO affects size-dependent anomalies during embryonic organogenesis, mouse embryos were cultured for two days with 300 ug/ml micro ZnO (mZnO;80±25 μm) and nZnO (< 100 nm) and the developmental changes were then investigated. Quantity of Zn by inductively coupled plasma mass spectrometry analysis, and expression patterns of various antioxidant enzymes in the embryos were investigated. Embryos exposed to mZnO or nZnO exhibited severe retardation of growth and development. In embryos exposed to mZnO and nZnO, yolk sac diameter, crown-rump length, and head length were significantly diminished. The morphological parameters, including yolk sac circulation, allantois, flexion, heart, hindbrain, midbrain, forebrain, otic system, optic system, branchial bars, maxillary process, mandibular process, olfactory system, caudal neural tube, forelimb, hindlimb, and somites in mZnO and nZnO-treated groups were significantly decreased. Zn absorption of the nZnO-treated group was significantly higher than that of the mZnO-treated group. Significantly decreased levels of CuZn-SOD, Mn-SOD, cGPx, and PHGPx mRNA were observed in the ZnO-treated group. In addition, antioxidant enzyme mRNA expressions of the nZnO group were significantly diminished, less than those of the mZnO treated group. These findings indicate that 300 ug/ml ZnO showed abnormality and nZnO may have a more severe effect than mZnO in developing embryos.
        4,000원
        360.
        2011.06 구독 인증기관 무료, 개인회원 유료
        This study was conducted in order to evaluate the effect of sericin-calcium (SC) as therapy for ovariectomy-induced osteoporosis in rats. Three weeks after ovariectomy (OVX), Sprague-Dawley rats were divided randomly into three groups: sham-operated group (Sham), ovariectomized group, and SC-treatment group (OVX+SC). Rats in the OVX+SC group were given drinking water containing 0.07% SC for eight weeks. Bone breaking force, mineralization, and blood parameters related to bone metabolism were analyzed. In OVX animals, blood concentration of 17β-estradiol showed a significant decrease, while osteocalcin and type I collagen C-terminal telopeptides (CTx) showed an increase. Breaking force of femurs as well as bone mineral density (BMD), ash, calcium, and phosphorus in femurs showed a significant decrease following OVX. Treatment with SC (0.07% in drinking water) resulted not only in remarkable restoration of the decreased 17β-estradiol and increased osteocalcin and CTx concentrations, but also led to recovery of decreased femoral breaking force, BMD, ash, calcium, and phosphorus. It is suggested that SC effectively improves bone density by preventing bone turnover-mediated osteocalcin, CTx, and minerals, and that it could be a potential candidate for use in therapy or prevention of post-menopausal osteoporosis.
        4,200원