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Cytological Evaluation and REBA HPV-ID HPV Testing of Newly Developed Liquid-Based Cytology, EASYPREP: Comparison with SurePath. KOREAN JOURNAL OF PATHOLOGY 2013; 47:265-74. [PMID: 23837020 PMCID: PMC3701823 DOI: 10.4132/koreanjpathol.2013.47.3.265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/28/2013] [Accepted: 06/03/2013] [Indexed: 11/17/2022]
Abstract
Background The objective of this study was to evaluate a newly-developed EASYPREP liquid-based cytology method in cervicovaginal specimens and compare it with SurePath. Methods Cervicovaginal specimens were prospectively collected from 1,000 patients with EASYPREP and SurePath. The specimens were first collected by brushing for SurePath and second for EASYPREP. The specimens of both methods were diagnosed according to the Bethesda System. Additionally, we performed to REBA HPV-ID genotyping and sequencing analysis for human papillomavirus (HPV) on 249 specimens. Results EASYPREP and SurePath showed even distribution of cells and were equal in cellularity and staining quality. The diagnostic agreement between the two methods was 96.5%. Based on the standard of SurePath, the sensitivity, specificity, positive predictive value, and negative predictive value of EASYPREP were 90.7%, 99.2%, 94.8%, and 98.5%, respectively. The positivity of REBA HPV-ID was 49.4% and 95.1% in normal and abnormal cytological samples, respectively. The result of REBA HPV-ID had high concordance with sequencing analysis. Conclusions EASYPREP provided comparable results to SurePath in the diagnosis and staining quality of cytology examinations and in HPV testing with REBA HPV-ID. EASYPREP could be another LBC method choice for the cervicovaginal specimens. Additionally, REBA HPV-ID may be a useful method for HPV genotyping.
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Diagnostic value of CA125 as a predictor of recurrence in advanced ovarian cancer. EUR J GYNAECOL ONCOL 2013; 34:148-151. [PMID: 23781586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PURPOSE The aim of this study was to establish the guidelines for detecting early recurrences of advanced epithelial ovarian cancer by use of the CA-125 level. MATERIALS AND METHODS Eighty-five of the patients who met the inclusion criteria were enrolled in this study. The authors examined 25 incremental changes of CA125 from one to 25 IU/ml, and compared the CA-125 value with other prognostic factors. Increases in the CA-125 level from the nadir level were expressed as CA-125- increments. RESULTS Among the 25 increments, a CA-125-8 (eight IU/ml) was selected as the predictor that was the most efficient and time-effective. CA-125-8 had a sensitivity of 91.5%, a specificity of 84.6%, a positive predictive value of 93.1%, a negative predictive value of 81.5%, an efficiency of 89.4%. and a median lead-time of 68.5 days (p <0.0001). CONCLUSION The authors suggest the incremented CA-125-8 as a predictor of recurrent advanced ovarian cancer.
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Expression of Müllerian inhibiting substance type II receptor and antiproliferative effects of MIS on human cervical cancer. Int J Oncol 2012; 40:2013-21. [PMID: 22344630 DOI: 10.3892/ijo.2012.1370] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 01/26/2012] [Indexed: 12/21/2022] Open
Abstract
This study aimed to analyze expression of Müllerian inhibiting substance type II receptor (MISRII) protein and mRNA in cervical neoplasia, to demonstrate the growth inhibition of cervical cancer cells by administration of highly purified recombinant human Müllerian inhibiting substance (MIS) and, furthermore, to evaluate the clinical significance of MIS as a biological modifier for MIS receptor expressing tumors. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for MISRII mRNA expression, and in situ hybridization and immunohistochemistry were used to observe expression, location of MISRII mRNA and protein, respectively. To demonstrate the effect of MIS on the viability of cervical cancer cells, methyl thiazole tetrazolium (MTT) assay was performed. Flow cytometry was used to evaluate the cell cycle distribution after exposure to MIS in cervical cancer cells, and the annexin-V-FITC staining method was performed to demonstrate apoptosis by MIS in cervical cancer cells. Expression of MISRII protein and mRNA were observed in all normal cervical and cervical carcinoma tissues. There was no significant difference in expression of MISRII protein and MISRII mRNA between normal cervical and cervical carcinoma tissues. MTT assay showed negative correlation between MIS exposure time and the viability of cervical cells (P=0.008). The changes in cell cycle distribution after MIS exposure suggest that MIS plays an important role in inducing cellular apoptosis by causing arrest at the G1 phase and increasing cells at sub-G0G1 phase. Annexin-V-FITC staining methods showed that cellular apoptosis was, respectively, 10.44 and 12.89% after 24 and 48 h of MIS exposure in cervical carcinoma cells. There was a negative correlation between cellular survival and MIS exposure time. This study demonstrates that MISRII is present on normal cervical and cervical carcinoma tissues, and MIS shows receptor-mediated antiproliferative effect on cervical cells in vitro. These data suggest that MIS may be used as a biological modifier or therapeutic modulator on MISRII-expressing tumors in the future.
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Residual tumor after the salvage surgery is the major risk factors for primary treatment failure in malignant ovarian germ cell tumors: a retrospective study of single institution. World J Surg Oncol 2011; 9:123. [PMID: 21988930 PMCID: PMC3214187 DOI: 10.1186/1477-7819-9-123] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 10/11/2011] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Malignant ovarian germ cell tumors are rare, and knowledge of their prognostic factors is limited, with little available randomized data. This study was conducted to evaluate the clinicopathologic characteristics of malignant ovarian germ cell tumors and to determine the association of their prognostic factors to primary treatment failure. METHODS The medical records of 57 patients with stages I to IV malignant ovarian germ cell tumor were retrospectively reviewed, and their clinicopathologic and treatment-related data were collected and analyzed. RESULTS The median age at the diagnosis was 23.3 years (range: 8-65 years), and the median follow-up period was 108 months (range: 48-205 months). The histological types of the tumors were immature teratoma (n = 24), dysgerminoma (n = 20), endodermal sinus tumor (n = 8), mixed germ cell tumor (n = 4), and choriocarcinoma (n = 1). 66.7% of the patients had stage I disease; 5.2%, stage II; 26.3%, stage III; and 1.8%, stage IV. After the initial surgery, 49 patients (86%) received cisplatin-based chemotherapy. The five-year survival rate was 96.5%. There were six primary treatment failures, with two of the patients dying of the disease, and the median time to the recurrence was 8 months. The histological diagnosis (P < 0.0001), tumor stage (P = 0.0052), elevation of beta-hCG (P = 0.0134), operation methods (P = 0.0006), and residual tumor after the salvage surgery (P < 0.0001) were significantly associated with the risk of primary treatment failure in the univariate analysis. In the multivariate analysis, the residual tumor after the salvage surgery was the only significant variable associated with primary treatment failure (P = 0.0011, Hazard ratio = 29.046, 95% Confidence interval 3.832-220.181). CONCLUSION Most malignant ovarian germ cell tumors have excellent prognoses with primary treatment, and good reproductive outcomes can be expected. Because primary treatment failure is associated with the residual disease after the salvage surgery, knowledge of the presence or absence of this risk factor may be helpful in risk stratification and individualization of adjuvant therapy in malignant ovarian germ cell tumors. Further large-scale prospective studies to confirm these results should be performed.
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The prognostic impact of duration of anemia during chemotherapy in advanced epithelial ovarian cancer. Oncologist 2011; 16:1154-61. [PMID: 21705663 DOI: 10.1634/theoncologist.2010-0236] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To propose a measure of anemia to be used as a prognostic factor for progression-free survival and overall survival in advanced epithelial ovarian cancer patients. PATIENTS AND METHODS Seventy-six patients with International Federation of Gynecology and Obstetrics stage III and stage IV epithelial ovarian cancer who had received at least six courses of platinum- and taxane-based systemic chemotherapy and achieved clinical or pathologic complete response were included. A novel prognostic factor based on the duration of anemia was proposed and the impact of anemia on progression-free and overall survival times was analyzed by a log-rank test and a Cox proportional hazards model. RESULTS We introduce a binary variable, Hb1020, that takes a value of 1 if the duration of a hemoglobin (Hb) level <10 g/dL is ≥20% of the total duration of chemotherapy. We propose Hb1020 as a potential prognostic factor for epithelial ovarian cancer. The 5-year progression-free survival rates were 48.4% in the Hb1020 = 0 group (duration of Hb <10 g/dL <20% of total duration) and 17.7% in the Hb1020 = 1 group (p = .026). The 5-year overall survival rates were 64.6% and 45.0%, respectively (p = .015). CONCLUSIONS Hb1020, based on the duration of anemia, is a potential prognostic factor for epithelial ovarian cancer. Using Hb1020, we will be able to administer highly optimized treatment for anemia to improve patient survival. Further independent studies are needed to confirm its prognostic role.
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Identification of characteristic molecular signature of Müllerian inhibiting substance in human HPV-related cervical cancer cells. Int J Oncol 2011; 39:811-20. [PMID: 21573503 DOI: 10.3892/ijo.2011.1042] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 04/11/2011] [Indexed: 12/30/2022] Open
Abstract
Müllerian inhibiting substance (MIS), also known as anti-Müllerian hormone (AMH), is a member of the transforming growth factor-β (TGF-β) superfamily that plays an important role in the mesenchymal-epithelial interaction, cell growth and proliferation, extracellular matrix production and tissue remodeling. Previously, we demonstrated that MIS suppressed ovarian cancer cell growth and suggested large-scale genetic elements that could be responsible for anti-neoplastic effects of MIS on ovarian cancer cells. In this study, we demonstrated the expression of MIS type II receptor (MISRII) in the human papillomavirus (HPV)-16-related cervical cancer cell lines CaSki and SiHa, and a non-HPV-related cervical cancer cell line, C33A. We also showed that MIS inhibited growth of cervical cancer cells, and induced cellular apoptosis of C33A. In addition, we identified a characteristic molecular signature of MIS in CaSki cells by using whole genome expression analysis. Of the 1,690 genes that showed significant expression changes by MIS, 21 genes were related to cell cycle; 13 genes to apoptosis; and 52 genes to the cancer pathway. On performing a search for cell cycle pathways in the KEGG pathway database, several gene expressions at the G1/S checkpoint were found. In particular, the expression of p16 and p107 increased and that of E2F2 and E2F3 decreased at an early stage, whereas the expression of E2F4 and E2F5 decreased at a later stage after MIS treatment. These data suggest that MIS produces activity against HPV16-related cervical cancers in vitro, and MIS may also be an effective targeted therapy for HPV16-related cervical cancer. Genetic data obtained here could be useful in determining the treatment strategy of MISR-expressing cervical tumors in the future.
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Consolidation hyperthermic intraperitoneal chemotherapy using paclitaxel in patients with epithelial ovarian cancer. J Surg Oncol 2009; 101:149-55. [DOI: 10.1002/jso.21448] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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The expression of Müllerian inhibiting substance/anti-Müllerian hormone type II receptor protein and mRNA in benign, borderline and malignant ovarian neoplasia. Int J Oncol 2009; 34:1583-91. [PMID: 19424576 DOI: 10.3892/ijo_00000288] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study investigated the expression patterns of Müllerian inhibiting substance/anti-Müllerian hormone type II receptor (MIS/AMHRII) and mRNA in various types of ovarian neoplasia and evaluated the clinical significance of MIS/AMH as a biological response modifier for MIS/AMHR-positive tumors. Reverse transcriptase polymerase chain reaction was used to detect MIS/AMHRII mRNA expression and in situ hybridization and immunohistochemistry were used to localize MIS/AMHRII mRNA and protein expression. The degree of expression was scored from 0 (no staining) to 3 (strong staining). There was no significant difference in expression intensity between MIS/AMHRII protein and mRNA on all ovarian samples whether benign or malignant. MIS/AMHRII protein and mRNA were weakly expressed on 45.45% of benign ovarian tumors. In borderline tumors, expression rates of MIS/AMHRII protein and mRNA were 77.78% with score 1.22 and 55.56% with score 1, respectively. In malignant ovarian tumors, expression rates of MIS/AMHRII protein and mRNA were 70% with score 1.23 and 75% with score 1.43, respectively. Among malignant ovarian tumors, sex cord stromal tumors showed the highest expression rate and the strongest intensity of MIS/AMHRII protein and mRNA followed by germ cell tumor and epithelial ovarian tumor. Non-epithelial malignant tumors showed stronger expression than that of epithelial tumors (P<0.05, P<0.001, respectively). In serous borderline malignant and malignant tumors, MIS/AMHRII protein and mRNA expression was 63.64 and 81.82% with expression intensity of 1.27 and 1.46, respectively, which were not statistically different from non-epithelial malignant tumors. MIS/AMHRII and MIS/AMHRII mRNA demonstrate significantly variable expression among different ovarian tumor types. Non-epithelial cell tumors show higher expression than those of epithelial cell tumors. The highest expression rate and intensity were observed on sex cord stromal tumors. MIS/AMHRII expression was not different according to the differentiation, but showed tissue-type specificity. These data support that MIS/AMH may be used as a biological modifier or therapeutic modulator in MIS/AMHRII-expressed ovarian tumors.
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Identification of large-scale characteristic genes of Müllerian inhibiting substance in human ovarian cancer cells. Int J Mol Med 2009; 23:589-96. [PMID: 19360316 DOI: 10.3892/ijmm_00000168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The purpose of this study was to investigate the large-scale characteristic molecular signature of Müllerian inhibiting substance (MIS) in human ovarian cancer cells through expression genomics. To understand the comprehensive molecular mechanisms by which MIS inhibits ovarian cancer cell growth, we identified the large-scale characteristic molecular changes elicited by MIS in the human ovarian cancer cell line OVCAR-8, using DNA microarray analysis. Combined serial gene expression analysis from 0 to 96 h after MIS treatment of OVCAR-8 cells resulted in 759 genes which showed at least a 2-fold change in overexpression or underexpression compared to non-treatment groups. Of the 759 outlier genes, 498 genes were mapped to known biological cellular processes, and the resultant major pathways included metabolism, signal transduction, cell growth and apoptosis. Among these pathways, 68 genetic elements were dissected as cell cycle-related genes induced by MIS. Although cellular phenotypic changes by MIS were observed after 24 h of treatment, the characteristic large-scale molecular changes were observed from 48 to 96 h of exposure to MIS. This finding may imply that the suppressive role of MIS on ovarian cancer cells could be cumulative in that the metabolic disturbance of MIS is followed by arrest at the G1/S cell cycle checkpoint. We suggest 759 outlier genes comprise the characteristic molecular signature of MIS, which may be responsible for the suppressive effect on OVCAR-8 cells. Although the precise biological mechanisms underlying these outlier genes should be validated, the genetic elements described herein provide promising therapeutic interventions for ovarian cancer.
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Treatment of ovarian cancer with paclitaxel- or carboplatin-based intraperitoneal hyperthermic chemotherapy during secondary surgery. Gynecol Oncol 2007; 106:193-200. [PMID: 17466362 DOI: 10.1016/j.ygyno.2007.03.019] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 03/02/2007] [Accepted: 03/09/2007] [Indexed: 02/08/2023]
Abstract
OBJECTIVE We aimed to evaluate the efficacy and feasibility of treating advanced ovarian cancer with paclitaxel or carboplatin in intraperitoneal hyperthermic chemotherapy (IPHC) during secondary surgery. METHODS We reviewed clinical data of 96 eligible patients with stage Ic-IIIc epithelial ovarian cancer. After primary staging operation and 6-12 cycles of adjuvant chemotherapy, 22 patients were treated with IPHC-paclitaxel (175 mg/m(2)) and 45 patients were treated with IPHC-carboplatin (350 mg/m(2)) during secondary surgery. Survival rates were compared with those of 29 patients treated with only conventional therapy (control group). RESULTS In stage III diseases, 5-year survival rates were 84.6% in IPHC-paclitaxel, 63.0% in IPHC-carboplatin (P=0.4098) and 32.8% in control group (vs. IPHC, P=0.0003). Three-year progression-free survival rates in stage III diseases were both 56.3% in IPHC-paclitaxel and IPHC-carboplatin (P=0.8911) and 16.7% in control group (vs. IPHC, P=0.0028). For the relative risk of disease progression yielded from multivariate analyses, hazard ratio of IPHC-paclitaxel was 0.281 (P=0.0039) and that of IPHC-carboplatin was 0.443 (P=0.0083). Like carboplatin (hazard ratio: 0.396, P=0.0004), IPHC-paclitaxel considerably decreased the risk of death (hazard ratio: 0.197, P=0.0253). CONCLUSION In advanced ovarian cancer, IPHC using paclitaxel or carboplatin during secondary surgery could be a candidate for regional consolidation therapy to prolong survival and hinder disease progression.
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Surgical Outcome of Endoscopic Carpal Tunnel Release in 100 Patients with Carpal Tunnel Syndrome. ACTA ACUST UNITED AC 2004; 47:261-5. [PMID: 15578337 DOI: 10.1055/s-2004-830075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The purpose of this study is to present the surgical outcome of endoscopic carpal tunnel release (ECTR) for the treatment of carpal tunnel syndrome (CTS). One hundred and thirty-one procedures (36 right hands, 33 left hands and 31 bilateral hands) of single portal ECTR were performed upon 100 patients (age range: 36-77 years, mean age: 52.9 years; 98 women and 2 men) with electrodiagnostically proven CTS for 2.5 years from 2001. Preoperative clinical severity and results of electrodiagnostic studies were compared with surgical outcomes at the minimal 3-month postoperative period. Among 131 cases 125 (95.4 %) with complete or significant relief of symptoms were satisfied and 6 (4.6 %) with partial or no relief of symptoms were dissatisfied. There were 2 cases of major complications (one with ulnar nerve injury and the other with ulnar artery injury) that developed in our early experience of ECTR and 1 case of recurrence. The grade of electrodiagnostic abnormalities was associated with surgical outcome but there was no statistical significance between them. The severity of clinical findings, age at onset and symptom duration were not correlated with surgical outcome. In conclusion, ECTR surgery was effective in relieving the symptoms of CTS with a low complication rate after the learning curve period. Thus, ECTR can be an alternative to the traditional open surgery and can be the first procedure for CTS with several advantages over open methods.
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Abstract
OBJECTIVES To evaluate the clinical effect of intraperitoneal hyperthermic chemotherapy (IPHC) in ovarian cancer patients. PATIENTS AND METHODS We retrospectively reviewed 117 stages Ic-III ovarian cancer patients, who were diagnosed at the Gynecology Department of Kangnam St. Mary's Hospital between January 1994 and January 2000. Of these, 57 patients underwent cytoreductive surgery (conventional treatment) with IPHC and 60 patients (control group) underwent conventional treatment only. IPHC consisted of administering a mixture of 350 mg/m(2) of carboplatin and 5,000,000 IU/m(2) of interferon-alpha, and maintaining the intraperitoneal temperature at 43-44 degrees C during surgery. RESULTS The overall 5-year survival rate was 58.6%; that of the IPHC group was 63.4% vs. 52.8% in the control group, with significantly higher survival in the IPHC group (P = 0.0078). Considering stage III ovarian cancer patients only (n = 74), the survival rate was 53.8% in the IPHC group (n = 35) and 33.3% in the control group (n = 39) and was significantly higher in the IPHC group (P = 0.0015). For stage III ovarian cancer patients whose tumor was reduced to less than 1 cm during a second procedure (n = 53), the 5-year survival rate was 65.6% in patients who underwent IPHC (n = 26) and 40.7% in the control patients (n = 27) (P = 0.0046). IPHC was an independent prognostic factor that was not affected by surgical staging, tumor size after second surgery, or patient age, according to a multivariate analysis (Hazard ratio = 0.496, P = 0.0176). CONCLUSION Our study suggests that IPHC is a promising new treatment modality in ovarian cancer.
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Morphological and photoelectrochemical characterization of core-shell nanoparticle films for dye-sensitized solar cells: Zn-O type shell on SnO2 and TiO2 cores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:4246-53. [PMID: 15969424 DOI: 10.1021/la036122x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Core-shell type nanoparticles with SnO2 and TiO2 cores and zinc oxide shells were prepared and characterized by surface sensitive techniques. The influence of the structure of the ZnO shell and the morphology ofnanoparticle films on the performance was evaluated. X-ray absorption near-edge structure and extended X-ray absorption fine structure studies show the presence of thin ZnO-like shells around the nanoparticles at low Zn levels. In the case of SnO2 cores, ZnO nanocrystals are formed at high Zn/Sn ratios (ca. 0.5). Scanning electron microscopy studies show that Zn modification of SnO2 nanoparticles changes the film morphology from a compact mesoporous structure to a less dense macroporous structure. In contrast, Zn modification of TiO2 nanoparticles has no apparent influence on film morphology. For SnO2 cores, adding ZnO improves the solar cell efficiency by increasing light scattering and dye uptake and decreasing recombination. In contrast, adding a ZnO shell to the TiO2 core decreases the cell efficiency, largely owing to a loss of photocurrent resulting from slow electron transport associated with the buildup of the ZnO surface layer.
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Purification, cDNA cloning and expression of an insect defensin from the great wax moth, Galleria mellonella. INSECT MOLECULAR BIOLOGY 2004; 13:65-72. [PMID: 14728668 DOI: 10.1111/j.1365-2583.2004.00462.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
An insect defensin, named Galleria defensin, was purified from the larval haemolymph of Galleria mellonella immunized against E. coli. The peptide was composed of forty-three amino acid residues containing six cysteines that might be engaged in intramolecular disulphide bridges. The primary structure of Galleria defensin shared about 90.7% identity to that of heliomicin, which was an insect defensin isolated from Heliothis virescens. The full-length cDNA encoding Galleria defensin was cloned from the fat body of the immunized G. mellonella larvae. Northern blot analysis revealed that Galleria defensin was expressed not only in the fat body but also in the midgut against invading bacteria into haemocoel. This is the first report presenting cDNA and expression of an insect defensin in the lepidopteran species.
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Detection of p16(INK4A) in the Mixed Cell Populations of Normal Peripheral Blood Mononuclear Cells and Cervical Cancer Cell Lines. Cancer Res Treat 2003; 35:254-60. [PMID: 26680944 DOI: 10.4143/crt.2003.35.3.254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
PURPOSE Human papilloma viruses (HPVs) play a central role in the pathogenesis of neoplastic lesions of the uterine cervix. The viral oncoprotein HPV E6 degrades the p53 protein, and the HPV E7 protein inactivates pRB and increases the expression of the CDK inhibitor, p16(INK4A). We investigated the usefulness of p16(INK4A) as a biologic marker for the cervical dysplastic and neoplastic cells. MATERIALS AND METHODS We examined the expression of p16(INK4A) and cytokeratin in a mixed population of normal peripheral blood mononuclear cells (PBMC) and the cervical cancer cell lines (HeLa, SiHa, and CasKi) using flow cytometry. RESULTS The DNA indices of the HeLa, SiHa and CasKi cell lines were 1.89, 1.53 and 1.75, respectively, indicating that these cells are aneuploid cells. Furthermore, the positive rate of p16(INK4A) expression was 86.7% for the HeLa mixed population, 85.6% for the SiHa mixed population, and 92.2% for the CasKi mixed population. According to the FL3A vs FL3W histogram, electrical gating of the HeLa, SiHa and CasKi mixed populations showed the expression levels of both cytokeratin and p16(INK4A) to be identical, at 86.6%, 84.8% and 85.0%, respectively. These findings revealed that almost all cells selected through electrical gating were cervical cancer cells originating from the epithelium and which expressed cytokeratin and p16(INK4A). On the other hand, when each mixed population was electrically gated for normal PBMC, we found that the PBMCs expressed neither cytokeratin nor p16(INK4A). CONCLUSION Using flow cytometry, we observed the enhanced expression of p16(INK4A) in cervical cancer cell lines. These. RESULTS suggest the usefulness of p16(INK4A) for the selective detection of cervical dysplastic and cancer cells in the liquid-based samples, which are taken from the cervices and contaminated with blood and stromal cells.
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Human secreted frizzled-related protein is down-regulated and induces apoptosis in human cervical cancer. Exp Cell Res 2002; 280:280-7. [PMID: 12413893 DOI: 10.1006/excr.2002.5649] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To identify genes involved in cervical carcinogenesis, the mRNA differential display method was used. A 220-bp cDNA fragment called CA11 was present in normal cervical tissue but not in primary cervical cancer tissue or cervical cancer cell lines. CA11 exhibited 98% homology with the recorded human secreted frizzled-related protein (hsFRP) sequence. A dominant hsFRP mRNA transcript of approximately 4.6 kb was present in three normal cervical tissues examined. Expression of the transcript was nearly absent from three cervical cancer tissues and from five human cervical cancer-derived cell lines. Results from in situ hybridization showed that the hsFRP transcript was confined to the normal cervical epithelial layer. When hsFRP-transfected HeLa and CUMC-6 cervical cancer cells were cultured in serum-free medium, most of the cells died within 8 days. This effect is associated with the apoptotic process. The caspase-3 inhibitor 1, Ac-DEVD-CHO, blocked hsFRP-induced apoptotic cell death. Additionally, cleavage of poly (ADP-ribose) polymerase in hsFRP-transfected cells was confirmed by colorimetric assay. These results indicate that the hsFRP gene probably functions as a tumor suppressor in normal cervical epithelium and down-regulation of hsFRP contributes to development of cervical cancer.
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Abstract
OBJECTIVE To investigate whether multiparameter flow cytometric analysis of solid tumor specimens, including gynecologic tumors, which were stained triply with phycoerythrin (PE), fluorescein isothiocyanate (FITC) and propidium iodide (PI), can be performed simultaneously without interference from normal diploid cell populations and spectral overlap on a standard flow cytometer. METHODS MCF-7 breast cancer cell lines and heterogeneous cell populations mixed with MCF-7 cells and human peripheral blood lymphocytes (PBL) were fixed with 1% paraformaldehyde and permeabilized with 100% methanol. Cytokeratin and several proliferation-associated cellular antigens (proliferating cell nuclear antigen (PCNA), p53, c-erbB/2 and c-myc) were labeled with PE and FITC, which was followed by DNA staining using PI. These labeled cells were measured on a standard FACScan flow cytometer equipped with a 488 nm single laser. RESULTS The coefficient of variation (CV) of the G0G1 peak of MCF-7 cells was 4.3 and the cell cycle phase fractions of G0G1, S and G2M were 44.9, 45.9 and 9.2%, respectively. Fluorescein isothiocyanate, PE and PI fluorescences were detected without interference. The MCF-7 cells expressed cytokeratin, PCNA, p53, c-erbB/2 and c-myc antigen. In the heterogeneous population of MCF-7 cells mixed with PBL, two cellular populations were clearly separated into diploid PBL and aneuploid MCF-7 cells without interference. The CV of G0G1 peak of PBL was 2.3 and the G0G1, S and G2M phase fractions were 85.5, 2.7 and 11.8%, respectively. The DNA index of MCF-7 cells was 1.7, which indicated that the MCF-7 cell line was composed of tumor cells with aneuploid DNA. The CV of the G0G1 peak of the MCF-7 cells was 4.2, and the cell cycle phase fractions were 47.5% for G0G1, 42.3% for S, and 10.2% for G2M. The MCF-7 cells expressed cytokeratin, but the PBL did not. CONCLUSIONS Multiparameter flow cytometer analysis was useful to determine DNA ploidy status, phase fraction of the cell cycle and expression of cellular antigens and selective cytokeratin expression allowed epithelial originated tumor cells to be differentiated from normal stromal cells. This analysis could be performed without interference of spectral overlaps of fluorochromes using software-based algorithmic compensation of spectral overlaps. Thus, this method offers new possibilities for multiparameter flow cytometric analysis and its use should be extended to future studies of the diagnosis, treatment and prediction of prognosis of the neoplasm.
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Abstract
The gonadotropin receptors are G-protein-coupled receptors with unique structural and functional features, consisting of two halves. The N-terminal extracellular half (exodomain) binds the hormones, whereas the C-terminal membrane-associated half (endodomain) is responsible for receptor activation. In this review, the novel ternary interactions, contact points and mutual modulations among the exodomain, endodomain and hormone for hormone binding and signal generation are described based on the latest observations. This discussion is contrary to the yiew that the exodomain and endodomain are independent, at least functionally, and provides new insights into the receptor mechanisms for the gonadotropins and other G-protein-coupled receptors.
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Alterations of HLA class I and class II antigen expressions in borderline, invasive and metastatic ovarian cancers. Exp Mol Med 2002; 34:18-26. [PMID: 11989974 DOI: 10.1038/emm.2002.3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
In an effort to understand whether HLA class I and II plays any role in the process of tumorigenesis and metastasis, we have immunohistochemically examined expression of HLA class I and II antigen by using the monoclonal antibodies (mAb) L368 (for beta2m of HLA class I), HC-10 (for HLA-B, C heavy chains), and LGII-612.14 (for HLA class II heavy chain) in 5 borderline serous malignancy (BSM), 20 serous adenocarcinomas (SA), 15 borderline mucinous malignancy (BMM), and 10 mucinous adenocarcinomas (MA) of human ovary tumor case tissues. In BSM, the distribution and intensity of HLA expressions failed to reach statistical significance. In SA, HLA class I beta2-microglobulin (beta2m), HLA-B, C heavy chains and HLA class II heavy chain antigen expressions were down-regulated. Although expressions of HLA-B, C heavy chains and class II heavy chain were down-regulated in metastatic SA, there were no differences in HLA expression levels between primary and metastatic lesions. In BMM, class II heavy chain expressions were down-regulated. In MA, beta2m, HLA-B, C heavy chains and class II heavy chain expressions were also down-regulated. Thus, we could distinguish the reduction or absence of HLA molecule expression was related to malignant potential. Loss of HLA class I and II molecules in invasive ovarian cancers raises the possibility that this could be a factor for tumor cells to retain invasiveness.
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Alterations of HLA class I and II antigen expression in preinvasive, invasive and metastatic cervical cancers. Exp Mol Med 2001; 33:136-44. [PMID: 11642549 DOI: 10.1038/emm.2001.24] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
HLA expression is altered in a large variety of human cancers. We performed immunohistochemical staining on tissues from normal, preinvasive, invasive and metastatic cervical cancer tissues using anti-HLA class I or class II antibody. In tissues from normal squamous epithelium, carcinoma in situ (CIS) and microinvasive carcinoma (MIC), the expressions of HLA-B, C heavy chains and class II heavy chain were significantly decreased as disease progressed. When the expression patterns were compared between primary and metastatic squamous cell carcinoma (SCC) lesions, statistically significant down-regulation of HLA class I and class II antigen in metastatic lesions was observed. The rates of HLA-B, C heavy chains and class II heavy chain expressions were all significantly down-regulated compared to the down-regulation rate of class I beta2-microglobulin (beta2m) in invasive squamous lesions, and the expressions of class II heavy chain in metastatic lesions was decreased further than that in primary lesions. Unlike SCC, the degree of HLA class I and class II loss was not evident as disease progressed in early stage of adenocarcinoma. In invasive adenocarcinoma lesions, only the expression of HLA-B, C heavy chains was decreased and no differences were seen in HLA-B, C heavy chain expression patterns between primary and metastatic lesions. These results suggest that alterations of HLA class I and II expressions seem to occur at a particular step in cervical cancer development and depend on tissue types: when the tumor becomes invasive and starts to metastasize.
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Polyhydroxylated alkaloids isolated from mulberry trees (Morusalba L.) and silkworms (Bombyx mori L.). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:4208-13. [PMID: 11559112 DOI: 10.1021/jf010567e] [Citation(s) in RCA: 256] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
New polyhydroxylated alkaloids, (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine-N-propionamide from the root bark of Morus alba L., and 4-O-alpha-D-galactopyranosyl-calystegine B(2) and 3 beta,6 beta-dihydroxynortropane from the fruits, were isolated by column chromatography using a variety of ion-exchange resins. Fifteen other polyhydroxylated alkaloids were also isolated. 1-Deoxynojirimycin, a potent alpha-glucosidase inhibitor, was concentrated 2.7-fold by silkworms feeding on mulberry leaves. Some alkaloids contained in mulberry leaves were potent inhibitors of mammalian digestive glycosidases but not inhibitors of silkworm midgut glycosidases, suggesting that the silkworm has enzymes specially adapted to enable it to feed on mulberry leaves. The possibility of preventing the onset of diabetes and obesity using natural dietary supplements containing 1-deoxynojirimycin and other alpha-glucosidase inhibitors in high concentration is of great potential interest.
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Abstract
The cytotoxicity of crude insect drugs was measured using HeLa cells originating from human cervix and uterine cancer, using the dye uptake assay in order to find potential anticancer agents. Three kinds of extracts (buffer, methanol and ethylacetate) were prepared from 26 insects and used as raw materials for the activity assay. Among these, the buffer extracts from Tabanus, Mylabris and Huechys showed a potent anticancer activity, and those from Catharsius, Red ant, Scorpion, Tabanus and Vespae Nidus showed a strong L-amino acid oxidase (AAO) activity as well as cytotoxicity. In contrast, buffer extracts from Gryllotalpa orientalis and Apriona germari larvae showed greater/more rapid Hela cell growth than that of other insects.
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Structures of ovine corticotropin-releasing factor and its Ala32 mutant as studied by CD and NMR techniques. J Biochem 2000; 127:687-94. [PMID: 10739963 DOI: 10.1093/oxfordjournals.jbchem.a022658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The corticotropin-releasing factor (CRF) is a 41-amino acid peptide-amide hormone, which mediates a general stress-response. It has been reported that the substitution of His-32 in the ovine CRF (oCRF) with Ala brings about a 4.5-fold increase in activity [Kornreich et al. (1992) J. Med. Chem. 35, 1870-76]. Here, we have determined the secondary structure of this Ala-substituted ovine CRF ([Ala32]oCRF) and compare it with that of oCRF using circular dichroism (CD) and NMR techniques in trifluoroethanol (TFE) solution, which is known to stabilize the alpha-helix formation. In contrast to an earlier report, it was observed the alpha-helical structure extends to the C-terminus of oCRF. By analyzing the CalphaH and NH chemical shifts, the properties of local structures of oCRF were elucidated. The oCRF and [Ala32]oCRF have stable alpha-helical structures in the middle region, regardless of pH and temperature, and the alpha-helix initiation regions of these peptides are stabilized as the pH is decreased. However, the [Ala32]oCRF has a more stable alpha-helical structure than oCRF in the vicinity of the substitution region, and it is thought that this is the cause of the increased activity of [Ala32]oCRF.
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Abstract
Nine flavonoids (1-9) were isolated from the leaves of Morus alba (Moraceae). The structures of compounds were determined to be kaempferol-3-O-beta-D-glucopyranoside (astragalin, 1) kaempferol-3-O-(6"-O-acetyl)-beta-D-glucopyranoside (2), quercetin-3-O-(6"-O-acetyl)-beta-D-glucopyranoside (3), quercetin-3-O-beta-D-glucopyranoside (4), kaempferol-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (5), quercetin-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (rutin, 6), quercetin-3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (7), quercetin-3,7-di-O-beta-D-glucopyranoside (8) and quercetin (9) on the basis of spectroscopic and chemical studies. Compounds 7 and 9 exhibited significant radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical.
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Gene, interaction, signal generation, signal divergence and signal transduction of the LH/CG receptor. Int J Gynaecol Obstet 1998; 60 Suppl 1:S9-20. [PMID: 9833610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Trophoblastic neoplasms and choriocarcinoma cells express high levels of the hCG receptor. The hCG receptor is encoded by a single gene in chromosome 2p21-p16, spanning over -70 kb with 11 exons and 10 introns. Multiple mRNA species are produced from the gene utilizing two proximal promoters and several Sp-1 elements as well as proximal and distal suppressors. In fact, regulatory proteins which bind to one of these suppressors are expressed less in choriocarcinoma cell lines than in placenta. The LH/CG receptor is comprised of two structurally and functionally distinct domains, extracellular N-terminal exodomain and membrane embedded endodomain. These two domains can separately be expressed and processed, including folding. The exodomain alone has the high affinity hormone binding site but is not capable of generating hormonal signal. In contrast, the endodomain alone has the site for receptor activation. These two domains contact each other in holo-receptor and split receptor. This interaction, particularly through exoloops 2 and 3, constrains the high affinity hormone binding at the exodomain. Conversely, the exodomain could be involved in receptor activation. Therefore, these two domains are not entirely independent although they can be independently synthesized and processed. The existing evidence indicate that hCG and the receptor undergo multiple stages of interactions leading to receptor activation. Initial high affinity binding of hCG to the exodomain results into conformational adjustments of the hCG/exodomain complex. This leads to the secondary, low affinity contact of the hCG/exodomain complex with the endodomain. This secondary contact is responsible for generating signals. They are transduced through TM to the cytoplasmic portion (cytoloops and the C-terminal tail) of the receptor and then, transferred to cytoplasmic signaling molecules, such as G protein. Mutations in the exodomain and endodomain (N-extension, exoloops, TM, cytoloops, and cytoplasmic tail) have the potential to interfere with receptor activation at different steps, signal generation, transduction and transfer. Binding of hCG to the LH/CG receptor are known to induce two signals, one for adenylyl cyclase/ cAMP and the other for phospholipase C/inositol phosphate/diacylglycerol. The cAMP signal and IP signal diverge at the surface of the receptor. These independent signals are separately transduced through the transmembrane domains to the cytoplasmic part of the receptor, indicating the existence of the distinct transducers for each of the signals. Furthermore, it is likely that the divergent signals are separately transferred to cytoplasmic signal molecules such as G protein. In addition, each of the cAMP signal and IP signal consists of at least three separate subsignals: affinity signal, maximal production (efficacy) signal and basal level signal. In heterodimeric hCG, there are distinct parts responsible for high affinity receptor binding and receptor activation. Particularly, the C-terminal reduces of the alpha subunit play a crucial role in receptor activation. This alpha subunit is shared with other glycoprotein hormones, follicle stimulating hormone and thyroid stimulating hormone. Interesting, the alpha C-terminal residues play distinct roles in all three hormones, despite its common nature.
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Abstract
Glucagon fragments dimyristoylphosphatidylcholine liposomes into discoidal complex under appropriate conditions. The concentration of glucagon required to fragment the vesicles increases with increasing pH, which appears to be related to the glucagon binding. It was also observed that the fragmentation is facilitated by NaCl, which is also due to increased glucagon binding. From the quenching of Trp fluorescence by doxyl group located at various positions of the acyl chain of the lipid, Trp of glucagon was found to be located close to the bilayer surface in the vesicular complex. However, the Trp fluorescence was quenched by the doxyl group in the discoidal complex to an equal extent regardless of the position of this spin label in the acyl chain. This and the results of second derivative UV spectroscopy of Tyr suggested that segments including Tyr-13 and Trp-25 are involved in the discoidal complex formation and that the orientation of glucagon is not normal to the bilayer surface.
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Roles of transmembrane prolines and proline-induced kinks of the lutropin/choriogonadotropin receptor. J Biol Chem 1997; 272:4166-71. [PMID: 9020129 DOI: 10.1074/jbc.272.7.4166] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The lutropin/choriogonadotropin receptor is a seven-helix transmembrane (TM) receptor. A unique feature of TM helices is the content of Pro, which generally is absent in alpha helices of globular proteins. Because Pro disrupts helices and introduces a approximately 26 degrees kink, it has been speculated that Pro plays a crucial role in the structure of TM helices, exoloops, and cytoloops of TM receptors. To examine the roles of the five TM Pros of the lutropin/choriogonadotropin receptor, these residues were individually substituted. Mutant receptors were examined for surface expression, hormone binding, and cAMP induction. Surface expression was monitored after introducing the flag epitope into the receptors. Flag epitopes slightly affected cAMP induction but not hormone binding or surface expression of receptors as monitored by immunofluorescence microscopy and 125I-anti-flag antibody. The results indicate that Pro479 in TM 4 and Pro598 in TM 7 play important yet contrasting roles. Pro479 is crucial for hormone binding at the cell surface but not after solubilization of the receptor. This is more likely due to the Pro side chain than the Pro-induced kink. Pro598 is important for surface expression. The kinks of Pro463 of TM 4, Pro562 of TM 6, or Pro591 of TM 7 are not important because the substitution of Phe for these residues did not significantly impact surface expression, hormone binding, and cAMP induction.
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Interaction, signal generation, signal divergence, and signal transduction of LH/CG and the receptor. RECENT PROGRESS IN HORMONE RESEARCH 1997; 52:431-53; discussion 454. [PMID: 9238862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The LH/CG receptor is comprised of two structurally and functionally distinct domains, extracellular N-terminal exodomain and membrane-embedded endodomain. These two domains can separately be expressed and processed, including folding. The exodomain alone has the high-affinity hormone binding site but is not capable of generating hormonal signal. In contrast, the endodomain alone has the site for receptor activation. These two domains contact each other in holo-receptor and split receptor. This interaction, particularly through exoloops 2 and 3, constrains the high-affinity hormone binding at the exodomain. Conversely, the exodomain could be involved in receptor activation. Therefore, these two domains are not entirely independent, although they can be independently synthesized and processed. The existing evidence indicates that hCG and the receptor undergo multiple stages of interactions leading to receptor activation. Initial high-affinity binding of hCG to the exodomain results in conformational adjustments of the hCG/exodomain complex. This leads to the secondary, low-affinity contact of the hCG/exodomain complex with the endodomain. This secondary contact is responsible for generating signals. They are transduced through transmembrane domains (TM) to the cytoplasmic portion (cytoloops and the C-terminal tail) of the receptor and then transferred to cytoplasmic signaling molecules such as G protein. Mutations in the exodomain and endodomain (N-extension, exoloops, TM, cytoloops, and cytoplasmic tail) have the potential to interfere with receptor activation at different steps: signal generation, transduction, and transfer. Binding of hCG to the LH/CG receptor is known to induce two signals, one for adenylyl cyclase/ cAMP and the other for phospholipase C/inositol phosphate/diacylglycerol. The cAMP signal and IP signal diverge at the surface of the receptor. These independent signals are separately transduced through the transmembrane domains to the cytoplasmic part of the receptor, indicating the existence of the distinct transducers for each of the signals. Furthermore, it is likely that the divergent signals are separately transferred to cytoplasmic signal molecules such as G protein. In addition, each cAMP signal and IP signal consists of at least three separate subsignals: affinity signal, maximal production (efficacy) signal, and basal level signal. In heterodimeric hCG there are distinct parts responsible for high-affinity receptor binding and receptor activation. Particularly, the C-terminal residues of the alpha subunit play a crucial role in receptor activation. This alpha subunit is shared with other glycoprotein hormones, follicle-stimulating hormone, and thyroid-stimulating hormone. Interestingly, the alpha C-terminal residues play distinct roles in all three hormones, despite its common nature.
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Abstract
It is known that the N-terminal half of the LH/CG receptor is responsible for high hCG binding whereas the C-terminal half is capable of receptor activation. Our results suggest that initial hCG binding at the high affinity site in the N-half receptor induces conformational adjustments. This leads to low affinity secondary contacts of the complex of hCG/the N-half receptor with the C-half receptor. This low affinity secondary contact is responsible for activating the receptor. This is based on the following observations. The C-terminal tail of hCG alpha is known to be involved in activation of the LH/CG receptor. In addition to hCG, we examined the C-terminal three residues (His90-Lys91-Ser92) of the common alpha subunit of FSH and TSH. The results show their differential roles in the three hormones. Ser92 is important for binding and cAMP induction of TSH but not for hCG and FSH. Lys91 is important for binding and cAMP induction of hCG, and cAMP induction but not binding of FSH. It is not important for binding or cAMP induction of TSH. His90 is important for all three hormones. When all three residues were truncated, FSH and TSH lose their affinity for binding and cAMP induction, whereas hCG is still capable of binding but not cAMP induction. Therefore, the three amino acids contribute differently in receptor binding and cAMP induction of hCG, FSH and TSH. Our data also indicate that the evolution of the alpha subunit has been constrained in order not to impair any of the hormones. This suggests that each hormone can be independently engineered to improve the potency. To chemically identify the contact site of the alpha C-tail of hCG in the LH/CG receptor, a decamer peptide corresponding to the alpha subunit sequence from His83 to Ser92 (peptide alpha 81-92) was derivatized with UV sensitive reagent, ABG and radio-iodinated. The resulting ABG-125I-peptide alpha 83-92 was capable of binding and activating the LH/CG receptor. Furthermore, it specifically photoaffinity-labeled the LH/CG receptor. In addition, the amino group of alpha Lys91 of peptide alpha 83-92 is crosslinked to a carboxyl group of the receptor, an indication of close association. Reciprocal mutagenesis of alpha Lys91 and Asp397 in exoloop 1 of the LH/CG receptor suggests the complementary of this pair in receptor activation but not the high affinity interaction of hCG and the receptor. In addition, Lys583 of exoloop 3 is also crucial for receptor activation. To test the conformational adjustment, ABG was attached to hCG alpha and reassociated with untreated beta to produce ABG-125I-alpha/beta. The extent of inter-subunit crosslinking of ABG-125I-alpha/beta bound to the receptor was two to three fold less than unbound ABG-125I-alpha/beta. This result indicates structural change at the subunit interface in response to hCG binding to the receptor.
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The luteinizing hormone/chorionic gonadotropin receptor has distinct transmembrane conductors for cAMP and inositol phosphate signals. J Biol Chem 1996; 271:19283-7. [PMID: 8702611 DOI: 10.1074/jbc.271.32.19283] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The luteinizing hormone/chorionic gonadotropin receptor is a member of the seven-transmembrane receptor family. It is coupled, presumably via Gs and Gq, to two signal pathways involving adenylyl cyclase/cAMP and phospholipase C/inositol phosphate (IP). Little is known about the events prior to G-protein coupling: for example, whether these signals are generated from a single or multiple independent origins and mechanisms, when and where they diverge, and how they are transduced. We report novel observations that the cAMP signal and the IP signal originate and diverge upstream of G-protein coupling. The generation of these two signals independently involves Lys583 in exoloop 3 of the rat receptor. For this study, Lys583 of the receptor was substituted with a panel of amino acids, and mutant receptors were assayed for hormone binding and induction of cAMP, inositol monophosphate, inositol bisphosphate, and inositol trisphosphate. No substitutions for Lys583 were permissible for cAMP induction, despite successful surface expression and hormone binding. In contrast, several substitutions were permissible for IP induction. Our results suggest two distinct transmembrane signal conductors for cAMP and inositol phosphate signals and imply particular models of receptor activation not previously suggested.
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Exoloop 3 of the luteinizing hormone/choriogonadotropin receptor. Lys583 is essential and irreplaceable for human choriogonadotropin (hCG)-dependent receptor activation but not for high affinity hCG binding. J Biol Chem 1996; 271:7301-4. [PMID: 8631747 DOI: 10.1074/jbc.271.13.7301] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The luteinizing hormone/choriogonadotropin (CG) receptor belongs to a subfamily of glycoprotein hormone receptors within the seven-transmembrane receptor family. It is comprised of an extracellular N-terminal half of 341 amino acids and a membrane-associated C-terminal half of 303 amino acids. The N-terminal half is capable of high affinity hormone binding whereas the C-terminal half is capable of low affinity hormone binding and receptor activation. However, the precise location of the receptor activation site is currently unknown. We present evidence for the first time that Lys583 of exoloop 3 is crucial and irreplaceable for receptor activation to induce cAMP synthesis. Exoloop 3 is comprised of 11 amino acids and flanked by two Lys residues, Lys573 and Lys583, that are located at the boundaries with the transmembrane columns 6 and 7, respectively. All substitutions including Arg for Lys583 did not affect the high affinity human CG binding, but they resulted in the complete loss of cAMP synthesis induced by human CG. Ala substitutions of the other amino acids in exoloop 3 did not make such a dramatic impact on cAMP induction. The Ala scan revealed two distinct groups of amino acids in terms of their importance in cAMP induction, one group being more important than the other. Interestingly, these two groups of amino acids are arranged in an alternate sequence. This result suggests a specific structure similar to a beta-like structure for exoloop 3.
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The folic acid requirements of starting broiler chicks fed diets based on practical ingredients. 2. Interrelationships with dietary methionine. Poult Sci 1995; 74:1456-62. [PMID: 7501590 DOI: 10.3382/ps.0741456] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Two experiments were conducted to determine the effects of dietary supplemental folic acid and methionine on the performance of starting broiler chicks for 18 d. Four levels of dietary folic acid (.24, .54, 1.14, and 2.34 mg/kg) and four levels of dietary methionine (.45, .53, .61, and .69%) were fed in a factorial design. There were three replicates of eight chicks each per each treatment. The basal diet was based on corn, isolated soybean protein, meat and bone meal, and fish meal. It contained adequate amounts of all nutrients except methionine and folic acid. Increased growth was observed in chicks fed the basal diet supplemented with either folic acid or methionine. Total dietary folic acid and methionine plus cysteine requirements for maximum growth were estimated to be 1.80 mg/kg and .85% in Experiment 1 and 1.47 mg/kg and .87% in Experiment 2, respectively. There were interactions between dietary folic acid and methionine on weight gain in both experiments. Chicks fed the diet containing 2.34 mg folic acid/kg tended to have depressed growth, as in previous experiments. There was a significant linear feed conversion response to folic acid in Experiment 1 and to methionine in Experiment 2. There were both linear and quadratic liver folic acid responses to dietary folic acid in both experiments. There was no indication that dietary methionine had any effect on liver folic acid content. No differences in bone ash, hemoglobin, hematocrit, or incidence of tibial dyschondroplasia were detected due to methionine or folic acid supplementation.
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The folic acid requirements of starting broiler chicks fed diets based on practical ingredients. 1. Interrelationships with dietary choline. Poult Sci 1995; 74:1447-55. [PMID: 7501589 DOI: 10.3382/ps.0741447] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Five experiments were conducted to evaluate the effect of dietary supplemental folic acid in starting broiler chick diets. In the first two experiments, basal diets based on corn and soybean meal contained 10 micrograms/kg vitamin B12 but no supplemental methionine or choline. Chicks showed curvilinear responses to folic acid supplementation with maximum growth and feed efficiencies from 1.45 mg/kg diet. The liver folic acid response was also curvilinear but reached a plateau at 1.70 mg folic acid/kg diet. The basal diet for three additional experiments contained soybean meal that had been washed with methanol to remove most of the choline. The basal diet contained only 750 mg/kg choline. Chicks exhibited a larger growth response to folic acid at low choline levels as evidenced by a significant folic acid by choline interaction. Choline and folic acid both increased tibia length and width. Folic acid supplementation increased but then decreased valgus deformity. Choline chloride supplementation also decreased the incidences of valgus and varus deformities and decreased bone ash, but increased the incidence of tibial dyschondroplasia. It is concluded that chicks fed practical ingredient-based diets require 1.3 mg folic acid/kg diet with low levels of choline, but only 1.2 mg folic acid/kg when choline is offered near the NRC recommended level of 1,300 mg/kg of choline.
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Abstract
Development of folate deficiency was evaluated in young chicks fed diets containing corn and soybean meal as major constituents. Folic acid deficiency, as indicated by retarded growth and feed efficiency, could be produced in 18-day-old chicks. Chicks fed the basal diet had increased growth when given supplements of either folic acid, choline Cl, or DL-methionine, but not vitamin B12. Relative liver size (grams per 100 g of body weight) was reduced by a methionine or methionine plus choline supplement in two experiments but by folic acid in only one of two experiments. Plasma hemoglobin was reduced by folic acid or a methionine and choline supplement after 42 days on the diets. Folic acid deficiency can be produced in young chicks with a diet based on practical ingredients. Purified diets or very high levels of antibiotic feeding are not necessary to produce folic acid deficiency as long as low levels of methionine and choline are present in the basal diet.
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Abstract
Four concentrations of Zn bacitracin (0, 50, 100 and 150 mg/kg) added to diets of two different planes of nutrition were fed to male broiler chicks for 7 weeks. Feeding broilers Zn bacitracin significantly improved growth rate and food conversion, and increased shank pigmentation. The effects of Zn bacitracin were independent of the plane of nutrition. Regression analyses revealed that the responses of birds were linear.
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Effects of pelleted or crumbled diets on the performance and the development of the digestive organs of broilers. Poult Sci 1986; 65:594-7. [PMID: 3703802 DOI: 10.3382/ps.0650594] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Two types (mash and crumble) of the starter ration (for 0 to 4 weeks of age) and two types (mash and pellets) of the finisher ration (for 4 to 8 weeks of age) were fed to broilers in a 2 X 2 factorial arrangement. Chicks fed the crumbled starter diet gained more weight and consumed more feed (P less than .01). Pelleting the finisher diet also significantly (P less than .01) improved weight gain and feed intake. Feeding the crumble during the starter period significantly (P less than .05) decreased gizzard weight at 4 weeks of age. Pelleting the finisher diet also significantly (P less than .01) reduced weights of the digestive tract and the gizzard at 8 weeks of age, compared to those fed the mash diet.
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