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11.
12.
Jia-You Fang Yann-Lii Leu Tsong-Long Hwang Hsiao-Chin Cheng Chi-Feng Hung 《European journal of pharmaceutical sciences》2003,19(4):253-262
To improve the drug permeation into and/or across the skin, essential oils extracted from Alpinia oxyphylla (AO) were evaluated using in vitro and in vivo permeation techniques with Wistar rats as the animal model. Hydrocarbons and oxygenated sesquiterpenes were the major components in the lower-polarity fraction (AO-1) and higher-polarity fraction (AO-2), respectively. Permeation of indomethacin was significantly enhanced after treatment with AO-1 and AO-2 in the in vitro and in vivo studies. AO-2 generally showed a higher ability to promote drug permeation compared to AO-1. The increment of skin/vehicle partitioning may be the predominant mechanism for this enhancing activity. Both transepidermal water loss (TEWL) and colorimetric evaluation showed limited irritation to skin by AO essential oils at the macroscopic level. Human skin fibroblasts were used to investigate the in vitro screening of skin toxicity. AO-1 slightly increased prostaglandin E(2) (PGE(2)) formation from skin fibroblasts. A striking result was observed with AO-2, which greatly inhibited the release of PGE(2). Moreover, both AO essential oils had no statistically significant effect on PGE(2) release by human lung epithelial cells. The results of this study indicate that skin disruption and inflammation do not necessary correspond to the enhancing efficiency of the enhancers tested. 相似文献
13.
Intrapericardial teratoma. Ultrasonic and pathological features 总被引:1,自引:0,他引:1
14.
15.
Shinkai T De Luca V Zai G Shaikh S Matsumoto C Arnold PD Hwang R King N Trakalo J Potapova N Wong G Hori H Wong AH Ohmori O Nakamura J Kennedy JL 《Psychiatric genetics》2004,14(3):177-180
OBJECTIVE: Oxidative stress such as free radical-mediated neuronal dysfunction may be involved in the pathophysiology of schizophrenia. The human glutathione peroxidase (GPX1) is a selenium-dependent enzyme, which plays an important role in the detoxification of free radicals. We therefore hypothesized that the GPX1 gene, which is located on chromosome 3p21.3, may be involved in the pathophysiology of schizophrenia. The aim of this study is to examine whether a potentially functional polymorphism, a proline (Pro) to leucine (Leu) substitution at codon 197 (Pro197Leu) of the human GPX1 gene, is associated with susceptibility to schizophrenia. METHODS: We genotyped the Pro197Leu polymorphism in a total of 113 nuclear families that had a proband with schizophrenia. Genetic association was tested using the transmission disequilibrium test (TDT), the sib transmission disequilibrium test (STDT), and the family-based association test (FBAT). RESULTS: The minor allele (Leu) frequency was calculated to be 0.282. We could not find significant transmission disequilibrium of the alleles for the Pro197Leu polymorphism in the GPX1 gene in association with the presence of schizophrenia in our family sample (TDT, chi2=0.03, degrees of freedom=1, P=0.86; combined TDT-STDT, Z'=-0.052, P=0.47; FBAT, Z=0.000, P=1.000). CONCLUSION: The results of this study suggest that the GPX1 polymorphism is unlikely to be associated with susceptibility to schizophrenia. 相似文献
16.
Seong-Keun Cho Jae-Hwan Kim Jong-Yi Park Yun-Jung Choi Jae-Il Bang Kyu-Chan Hwang Eun-Jeong Cho Sea-Hwan Sohn Sang Jun Uhm Deog-Bon Koo Kyung-Kwang Lee Teoan Kim Jin-Hoi Kim 《Developmental dynamics》2007,236(12):3369-3382
Somatic cell nuclear transfer (scNT) is a useful way to create cloned animals. However, scNT clones exhibit high levels of phenotypic instability. This instability may be due to epigenetic reprogramming and/or genomic damage in the donor cells. To test this, we produced transgenic pig fibroblasts harboring the truncated human thrombopoietin (hTPO) gene and used them as donor cells in scNT to produce first-generation (G1) cloned piglets. In this study, 2,818 scNT embryos were transferred to 11 recipients and five G1 piglets were obtained. Among them, a clone had a dimorphic facial appearance with severe hypertelorism and a broad prominent nasal bridge. The other clones looked normal. Second-generation (G2) scNT piglets were then produced using ear cells from a G1 piglet that had an abnormal nose phenotype. We reasoned that, if the phenotypic abnormality of the G1 clone was not present in the G2 and third-generation (G3) clones, or was absent in the G2 clones but reappeared in the G3 clones, the phenotypic instability of the G1 clone could be attributed to faulty epigenetic reprogramming rather than to inherent/accidental genomic damage to the donor cells. Blastocyst rates, cell numbers in blastocyst, pregnancy rates, term placenta weight and ponderal index, and birth weight between G1 and G2 clones did not differ, but were significantly (P < 0.05) lower than control age- and sex-matched piglets. Next, we analyzed global methylation changes during development of the preimplantation embryos reconstructed by donor cells used for the production of G1 and G2 clones and could not find any significant differences in the methylation patterns between G1 and G2 clones. Indeed, we failed to detect the phenotypic abnormality in the G2 and G3 clones. Thus, the phenotypic abnormality of the G1 clone is likely to be due to epigenetic dysregulation. Additional observations then suggested that expression of the hTPO gene in the transgenic clones did not appear to be the cause of the phenotypic abnormality in the G1 clones and that the abnormality was acquired by only a few of the G1 clone's cells during its gestational development. 相似文献
17.
Hwang JL Huang LW Hsieh BC Tsai YL Huang SC Chen CY Hsieh ML Chen PH Lin YH 《Human reproduction (Oxford, England)》2003,18(1):45-49
BACKGROUND: The introduction of GnRH antagonists such as cetrorelix acetate has made possible the simplification of ovarian stimulation. However, the most effective protocol for their administration has not yet been clearly defined. METHODS: Forty women with male-factor infertility undergoing 40 ICSI cycles were included in the study. Clomiphene citrate at 100 mg a day was given from cycle day 3 through day 7. hMG at 150 IU was given on cycle days 4, 6 and 8, and was adjusted from day 9 according to the follicular and hormone responses. Cetrorelix acetate at 2.5 mg was administered when the leading follicle reached 14 mm. The remaining 0.5 mg was divided into two 0.25 mg injections for possible later use. Serum FSH, LH, estradiol and progesterone levels were measured daily from the day of cetrorelix acetate injection until hCG was given. RESULTS: Serum LH level was suppressed effectively for 4 days. Four patients (10%) needed one or two additional injections of 0.25 mg cetrorelix acetate. No premature LH surge was detected in any of the women treated. Sixteen women became pregnant (40%), of which 14 pregnancies (35%) were ongoing at the time of writing. CONCLUSIONS: This study demonstrates that this new protocol is feasible for couples with male-factor infertility undergoing ICSI. 相似文献
18.
Bedside to bench and back again: how animal models are guiding the development of new immunotherapies for cancer 总被引:3,自引:0,他引:3
Finkelstein SE Heimann DM Klebanoff CA Antony PA Gattinoni L Hinrichs CS Hwang LN Palmer DC Spiess PJ Surman DR Wrzesiniski C Yu Z Rosenberg SA Restifo NP 《Journal of leukocyte biology》2004,76(2):333-337
Immunotherapy using adoptive cell transfer is a promising approach that can result in the regression of bulky, invasive cancer in some patients. However, currently available therapies remain less successful than desired. To study the mechanisms of action and possible improvements in cell-transfer therapies, we use a murine model system with analogous components to the treatment of patients. T cell receptor transgenic CD8+ T cells (pmel-1) specifically recognizing the melanocyte differentiation antigen gp100 are adoptively transferred into lympho-depleted mice bearing large, established, 14-day subcutaneous B16 melanoma (0.5-1 cm in diameter) on the day of treatment. Adoptive cell transfer in combination with interleukin interleukin-2 or interleukin-15 cytokine administration and vaccination using an altered form of the target antigen, gp100, can result in the complete and durable regression of large tumor burdens. Complete responders frequently develop autoimmunity with vitiligo at the former tumor site that often spreads to involve the whole coat. These findings have important implications for the design of immunotherapy trials in humans. 相似文献
19.
Yu-Li Liu Cathy Shen-Jang Fann Chih-Min Liu Jer-Yuarn Wu Shuen-Iu Hung Hung-Yu Chan Jiahn-Jyh Chen Chin-Yu Lin Shih-Kai Liu Ming H Hsieh Tzung-Jeng Hwang Wen-Chen Ouyang Chun-Ying Chen Jin-Jia Lin Frank Huang-Chih Chou Ching-Mo Chueh Wei-Ming Liu Ming-Min Tsuang Stephen V Faraone Ming T Tsuang Wei J Chen Hai-Gwo Hwu 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(4):418-420
Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers. 相似文献
20.
Molecular and genetic characterizations of five pathogenic and two non-pathogenic monoclonal antiphospholipid antibodies 总被引:3,自引:0,他引:3
Chukwuocha RU Zhu M Cho CS Visvanathan S Hwang KK Rahman A Chen PP 《Molecular immunology》2002,39(5-6):299-311
Antiphospholipid syndrome (APS) is an autoimmune disease that is characterized by thrombosis, recurrent fetal loss and thrombocytopenia. Antiphospholipid antibodies, detected by enzyme-linked immunoabsorbent assays (aCL) and/or in vitro blood clotting assays (LAC) are strongly associated with APS. Both the molecular structures used by pathogenic antiphospholipid antibodies and the genetic mechanisms leading to their production are unknown. We describe here the variable region genes of seven IgG antiphospholipid antibodies derived from two APS patients. Of these, five are pathogenic as defined in a mouse model of thrombosis and two are not. Analyses of the expressed variable region genes show no preferential V gene usage. However, similar to anti-DNA antibodies, pathogenic antiphospholipid antibodies contain an increased number of arginine residues in the third complimentarity-determining region (CDR3) of their H chains. The increased accumulation of arginine residues in the V(H) CDR3 may act to enhance antigen binding, promote disease and point to the importance of the H chain in the pathogenic potential of certain antiphospholipid antibodies. 相似文献