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[Effects of salivary microbiota on tryptophan-aryl hydrocarbon receptor signaling axis in mice with periodontitis]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 2022; 57:595-603. [PMID: 35692003 DOI: 10.3760/cma.j.cn112144-20220323-00126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To study the effects of salivary microbiota in patients with periodontitis on the tryptophan-aryl hydrocarbon receptor (AhR) signaling axis in mice with periodontitis and to provide theoretical basis as well as new ideas for the influences of periodontitis on systemic metabolism. Methods: Salivary microbiota of 12 healthy individuals and 14 patients with periodontitis were collected in Nanjing Stomatological Hospital, Medical School of Nanjing University from June to December of 2020. According to the random number table method, twenty-four mice were randomly divided into three groups: Sham group (control group), P group (periodontitis patients' salivary microbiota group) and H group (periodontal healthy individuals' salivary microbiota group). The maxillary second molars of all mice were treated with silk thread ligation to induce periodontitis. Phosphate buffer as well as salivary microbiota of periodontal healthy individuals and periodontitis patients were gavaged into periodontitis mice for 2 weeks. The expression of inflammatory factors in mice serum were detected by enzyme linked immunosorbent assay, and the expression of tryptophan and indole metabolites in intestinal tract and serum were detected by liquid chromatography-mass spectrometry. The expression of AhR in intestinal tract of mice was detected by immunohistochemistry and quantitative real time-PCR while gut microbiota constitution was detected by 16S rRNA gene sequencing. The remaining saliva samples of periodontitis patients and periodontal healthy individuals were applied to detect the expression of tryptophan and indole metabolites themselves. Results: The salivary microbiota of periodontitis patients could induce the expression of interleukin-1β [P group: (162.38±39.46) pg/ml, H group: (82.83±20.01) pg/ml; t=4.40, P=0.001) and tumor necrosis factor-α [P group: (361.16±123.90) pg/ml, H group: (191.66±106.87) pg/ml; t=2.54, P=0.030) in serum of periodontitis mice, and reduce the expression of AhR in colon (P group: 1.18±0.05, H group:1.83±0.47; t=3.09, P=0.015) and ileum (P group: 0.80±0.13, H group: 1.18±0.11; t=4.93, P=0.001). After gavage of salivary microbiota of periodontitis patients to the mice, tryptophan (P group: (18.1±3.8)×107, H group: (26.6±6.6)×107; t=2.49, P=0.037] and indole lactic acid [P group: (1.9±0.7)×107, H group: (3.7±0.6)×107; t=4.49, P=0.002) in serum of periodontitis mice were significantly decreased, but was relatively disorder in intestinal tract. However, the expressions of tryptophan and indole metabolites in saliva of periodontitis patients were higher than those of periodontal healthy individuals. There were significant differences in indole propionic acid [P group: (1 239.39±818.72) nmol/L, H group: (56.96±38.33) nmol/L; t=2.83, P=0.022]. What we find noteworthy was that the expressions of indolelactic acid metabolism in saliva, serum and intestinal were consistent, and salivary microbiota of periodontitis patients could reduce the relative abundance of indolelactic acid-producing bacteria in the gut, suggesting that the salivary microbiota of periodontitis patients might affect the expression of AhR through gut microbiota disorder and indolelactic acid downregulation. Conclusions: Salivary microbiota in patients with periodontitis may affect the systemic inflammatory state through down-regulating the expression of tryptophan-AhR signal axis.
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[Current status and research progress of third-line treatment for patients with gastric cancer in China]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2020; 42:983-988. [PMID: 33342152 DOI: 10.3760/cma.j.cn112152-20190910-00589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Gastric cancer (GC) is one of the most common malignant tumors in the world. The prognosis of advanced GC is extremely poor, characterized by the high recurrence or disease progression rate after the first-line chemotherapy, and the extremely low long-term survival rate. Meanwhile, the options for subsequent treatment are limited. Studies have shown that the third-line therapy can provide significant survival benefits for selected patients with advanced GC. Currently, a series of randomized controlled trials and real-world studies related to chemotherapy, targeted therapy, and immunotherapy are conducted. In addition, the explorations of combination therapy, and screening the optimal clinical features or predictive biomarkers for the suitable population who might benefit from the third-line regimens are the hot spots for researchers. This article will provide a detailed overview of the current status and progress of the third-line treatment for advanced GC, and to illustrate the characteristics of Chinese GC treatment.
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[The diagnostic value of immunohistochemical triple antibody cocktail for microinvasive breast carcinoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2020; 49:1061-1063. [PMID: 32992425 DOI: 10.3760/cma.j.cn112151-20191219-00813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Perioperative outcomes of women with and without class III obesity undergoing hysterectomy for endometrioid endometrial cancer: A population-based study. Gynecol Oncol 2020; 158:681-688. [PMID: 32571681 DOI: 10.1016/j.ygyno.2020.06.480] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/04/2020] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Population-based data on perioperative complications among women with endometrial cancer and severe obesity are lacking. We evaluated 30-day complication rates among women with and without class III obesity (body mass index ≥ 40 kg/m2) undergoing primary surgical management for endometrioid endometrial cancer (EEC), and how outcomes differed according to surgical approach (open vs. minimally invasive). METHODS We performed a retrospective population-based cohort study of women with EEC undergoing hysterectomy in Ontario, Canada, between 2006 and 2015. We evaluated perioperative complications in the whole cohort, and in a 1:1 matched analysis using hard and propensity score matching to ensure similar distributions of patient, tumour, provider and institution-level factors between women with and without class III obesity (identified using a surgical billing code). The primary outcome of interest was the 30-day perioperative complication rate. RESULTS 12,112 women met inclusion criteria; 2697 (22.3%) had class III obesity. We matched 2320 (86%) women with class III obesity to those without. The composite complication rate was significantly higher among women with class III obesity (23.2% vs. 18.4%, standardized mean difference [SMD] = 0.12), primarily due to wound infection/disruption (12.1% vs. 6.2%). There was no difference in outcomes for women with and without class III obesity when a minimally invasive approach was used. CONCLUSIONS Wound infection/disruption was increased for women with class III obesity compared to women without. Otherwise, perioperative complications were similar between the matched pairs. When minimally invasive approaches were used, women with class III obesity had a similar risk of complications as women without obesity.
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Temperature and excitation wavelength dependence of circular and linear photogalvanic effect in a three dimensional topological insulator Bi 2Se 3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:415702. [PMID: 31220819 DOI: 10.1088/1361-648x/ab2b55] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The circular (CPGE) and linear photogalvanic effect (LPGE) of a three-dimensional topological insulator Bi2Se3 thin film of seven quintuple layers excited by near-infrared (1064 nm) and mid-infrared (10.6 [Formula: see text]m) radiations have been investigated. The comparison of the CPGE current measured parallel and perpendicular to the incident plane, together with the comparison of the CPGE current under front and back illuminations, indicates that the CPGE under front illumination of 1064 nm light is dominated by the top surface states of the Bi2Se3 thin film. The CPGE current excited by 10.6 [Formula: see text]m light is about one order larger than that excited by 1064 nm light, which may be attributed to the smaller cancelation effect of the CPGE generated in the two-dimensional electron gas when excited by 10.6 [Formula: see text]m light. Under the excitation of 1064 nm light, the LPGE current is dominated by the component which shows an even parity of incident angles, while the LPGE current excited by 10.6 [Formula: see text]m light is mainly contributed by the component which is an odd parity of incident angles. Both of the CPGE and LPGE currents excited by 1064 nm decrease with increasing temperature, which may be owing to the decrease of the momentum relaxation time and the stronger electron-electron scattering with increasing temperature, respectively.
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The generation of two specific cancer costing algorithms using Ontario administrative databases. ACTA ACUST UNITED AC 2019; 26:e682-e692. [PMID: 31708661 DOI: 10.3747/co.26.5279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cancer treatment and management have become increasingly economically burdensome. Consequently, to help with planning health service delivery, it is vital to understand the associated costs. Administrative databases can be used to help understand and generate real-world system-level costs. Using databases to generate costs can take one of two approaches: top-down or bottom-up. Top-down approaches disaggregate the total health care spending from a global health care budget by sector and provider. A bottom-up approach begins with individual-level health care use and its costs, which are then aggregated.
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Effects of an Oral-Pharyngeal Motor Training Programme on Children with Obstructive Sleep Apnea Syndrome in Hong Kong: A Retrospective Pilot Study. Hong Kong J Occup Ther 2018; 30:1-5. [PMID: 30186074 PMCID: PMC6092010 DOI: 10.1016/j.hkjot.2017.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 08/20/2017] [Accepted: 09/05/2017] [Indexed: 11/30/2022] Open
Abstract
Background This study aimed to investigate the effects of an oropharyngeal motor
training programme on children with Obstructive Sleep Apnea Syndrome (OSAS)
in Hong Kong. Methods In this retrospective study, we reviewed the outcomes of 10 children with
OSAS who had received an oropharyngeal motor training programme in
Occupational Therapy Department of an acute hospital in Hong Kong over a
1-year programme. Each participant attended an individual oropharyngeal
motor training programme plus a follow-up session after 2 months. The
training programme consisted of 10 individual mobilization exercises
involving the orofacial and pharyngeal area for 45 minutes. Each exercise
had to be repeated for 10 times. Three outcome measures were chosen to study
the effectiveness of the training programme including tongue strength,
tongue endurance level and orofacial function. Tongue strength and tongue
endurance level were assessed using the Iowa Oral Pressure Instrument
(IOPI). The Nordic Orofacial Test-Screening (NOT-S) Assessment was used to
assess the orofacial function. Seven out of 10 participants completed the
training programme and attended the follow-up session after two months. Results The tongue strength and the scores of NOT-S of the 7 participants were found
to have significant improvement after training. However, there was no
significant difference in tongue endurance level. Conclusion The findings of this study support the role of occupational therapist in
oromotor training modalities to improve the respiratory function for
children with OSAS in Hong Kong. Copyright © 2017, Hong Kong Occupational
Therapy Association. Published by Elsevier (Singapore) Pte Ltd. This is an
open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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[Clinical value of T-cell interferon releases detection of tuberculosis infection assay in quick diagnosis of spinal tuberculosis]. ZHONGHUA YI XUE ZA ZHI 2017; 96:2179-81. [PMID: 27464546 DOI: 10.3760/cma.j.issn.0376-2491.2016.27.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To evaluate the value of T-cell interferon releases detection of tuberculosis infection(T-SPOT.TB)assay in quick diagnosis of spinal tuberculosis. METHODS From January 2012 to June 2015, a group of 122 diagnosed patients with spinal tuberculosis in the Qingdao Municipal Chest Hospital and a group of 86 patients suspected with spinal tuberculosis in Department of Orthopaedic, the Qingdao Third People's Hospital were accepted to undergone TB-DOT, T-SPOT.TB and TB-DNA PCR tests Department of Clinical Laboratory. RESULTS The sensitivity of TB-DOT, T-SPOT.TB and TB-DNA PCR tests were 69.7%, 86.1% and 56.6%, respectively.The sensitivity of T-SPOT.TB was significantly higher than TB-DOT and TB-DNA PCR tests (χ(2)=9.51, P<0.05; χ(2)=25.96, P<0.05). The specificity of TB-DOT, T-SPOT.TB and TB-DNA PCR tests were 62.8%, 88.3% and 91.9%, respectively.The specificity of T-SPOT.TB was significantly higher than TB-DOT test (χ(2)=15.25, P<0.05). CONCLUSIONS T-SPOT.TB assay possesses high sensitivity and specificity in quick diagnosis of patients with spinal tuberculosis, which is valuable in diagnosis of spinal tuberculosis.
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[Second-line treatment for metastatic or locally advanced gastric cancer]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2016; 38:721-724. [PMID: 27784452 DOI: 10.3760/cma.j.issn.0253-3766.2016.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Gastric cancer is one of the major causes of cancer-related deaths. Many patients with metastatic gastric cancer after first-line chemotherapy received salvage chemotherapy in routine clinical practice. Recent phase Ⅲ trials demonstrated substantial prolongation of overall survival to support this chemotherapy or targeted therapy as a second-line treatment. Both ramucirumab monotherapy and ramucirumab plus paclitaxel were approved by FDA in patients with previously treated advanced gastric or gastroesophageal junction adenocarcinoma. In addition, paclitaxel, irinotecan, or docetaxel monotherapy is also recommended for preferred regimens. This review will summarize chemotherapy or targeted therapy as a second-line treatment in advanced gastric cancer.
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Abstract
OBJECTIVE Costs for radiation therapy (rt) and the methods used to cost rt are highly diverse across the literature. To date, no study has compared various costing methods in detail. Our objective was to perform a thorough review of the radiation costing literature to identify sources of costs and methods used. METHODS A systematic review of Ovid medline, Ovid oldmedline, embase, Ovid HealthStar, and EconLit from 2005 to 23 March 2015 used search terms such as "radiation," "radiotherapy," "neoplasm," "cost," " cost analysis," and "cost benefit analysis" to locate relevant articles. Original papers were reviewed for detailed costing methods. Cost sources and methods were extracted for papers investigating rt modalities, including three-dimensional conformal rt (3D-crt), intensity-modulated rt (imrt), stereotactic body rt (sbrt), and brachytherapy (bt). All costs were translated into 2014 U.S. dollars. RESULTS Most of the studies (91%) reported in the 33 articles retrieved provided rt costs from the health system perspective. The cost of rt ranged from US$2,687.87 to US$111,900.60 per treatment for imrt, followed by US$5,583.28 to US$90,055 for 3D-crt, US$10,544.22 to US$78,667.40 for bt, and US$6,520.58 to US$19,602.68 for sbrt. Cost drivers were professional or personnel costs and the cost of rt treatment. Most studies did not address the cost of rt equipment (85%) and institutional or facility costs (66%). CONCLUSIONS Costing methods and sources were widely variable across studies, highlighting the need for consistency in the reporting of rt costs. More work to promote comparability and consistency across studies is needed.
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Congenital anterior urethrocutaneous fistula at the penoscrotal junction with proximal penile megalourethra: A case report. J Radiol Case Rep 2016; 10:33-7. [PMID: 27200160 DOI: 10.3941/jrcr.v10i2.2533] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Congenital anterior urethrocutaneous fistula and megalourethra are both rare anomalies. These anomalies are commonly associated with other anorectal or genitourinary anomalies and evaluated with voiding cystourethrography. We examined a 34-month-old boy who presented with a fistula at the penoscrotal junction. A voiding cystourethrogram showed a jet of urine coming through the fistula and proximal saccular dilatation of the penile urethra. We present the imaging findings of the first case of an association between a congenital anterior urethrocutaneous fistula at the penoscrotal junction and a proximal penile megalourethra. We also discuss the etiology, management, and differential diagnosis of this entity, and review the literature.
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Expression Patterns of Three Genes Under Short and Long Term Cold Exposure in Thitarodes pui (Lepidoptera: Hepialidae), A Host of Ophiocordyceps sinensis. CRYO LETTERS 2016; 37:432-439. [PMID: 28072431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
UNLABELLED BACKGROUND: Thitarodes larvae are the host of the caterpillar fungus Ophiocordyceps sinensis. Low temperature is the main environmental limitation for larvae growth. OBJECTIVE To better understand the cold adaption process in T. pui larvae, the expression patterns of trehalose-6-phosphate synthase (TpTPS), heat shock protein 70 (TpHSP70), and heat shock protein 90 (TpHSP90) were investigated upon short and long-term exposure to 0°C. MATERIALS AND METHODS The 6th instar T. pui larvae were collected in July 2013. TpTPS was firstly sequenced and expression patterns of TpTPS, TpHSP70 and TpHSP90 were investigated using quantitative PCR. RESULTS Full-length cDNA of TpTPS was 3,012 bp, with an open reading frame of 2,472 bp and an encoding protein of 823 amino acids. TpTPS up-regulation was induced by cold exposure. TpHSP70 expression is altered by cold exposure, but remained low. TpHSP90 expression was obviously up regulated in long-term cold stimulation. CONCLUSION All three genes (TpTPS, TpHSP70 and TpHSP90) have likely contributed to cold tolerance in T. pui larvae, TpTPS and TpHSP90 potentially being more important.
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Molecular cloning and characterization of GbMECT and GbMECP gene promoters from Ginkgo biloba. GENETICS AND MOLECULAR RESEARCH 2015; 14:15112-22. [PMID: 26634474 DOI: 10.4238/2015.november.24.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ginkgolides are key pharmaceutical components in Ginkgo biloba. Using the cDNA sequence of the MECP and MECT genes to design primers, we obtained the promoters of these genes from Ginkgo genomic DNA using the genome walking method. The two promoters were 744 and 982 bp in length, respectively. The cis-elements of the GbMECPs and GbMECT promoters were predicted and analyzed using the plant cis-acting regulatory element database. We found major cis-elements in the sequence of the GbMECT and GbMECPs promoters. The GbMECP promoter contains six TATA boxes and eight CAAT boxes. The GbMECT contains five TATA boxes and seven CAAT boxes. Furthermore, some cis-elements in the promoters of GbMECPs and GbMECT included hormone and light-regulated elements, UB-B-induced elements, and stress-related dehydration-responsive elements. Expression analysis results showed that the MECP gene is mainly involved in responses to CCC (cycocel) and UV-B, and that MECT is mainly involved in responses to wounding treatment. These results also showed that the expression model was consistent with the cis-elements present. During the annual growth cycle, the level of GbMECPs was significantly correlated with terpene lactones accumulation in leaves. A fitted quadratic curve showed the best model for correlating GbMECPs with terpene lactones in leaves. These results will help us to understand the transcriptional regulatory mechanisms involved in key gene expression and ginkgolide accumulation in G. biloba.
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Dietary Supplementation of Magnesium Sulfate during Late Gestation and Lactation Affects the Milk Composition and Immunoglobulin Levels in Sows. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 27:1469-77. [PMID: 25178299 PMCID: PMC4150180 DOI: 10.5713/ajas.2014.14190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/01/2014] [Accepted: 06/10/2014] [Indexed: 11/27/2022]
Abstract
This experiment was conducted to investigate the effects of dietary supplementation of magnesium sulfate (MgSO4) during late gestation and lactation on sow and litter performance, fecal moisture, blood biochemistry parameters, immunoglobulin levels and milk composition in sows. Forty-eight sows (Yorkshire×Landrace, 4th to 5th parity) were randomly allocated to 1 of 4 dietary treatments supplemented with 0, 200, 400, or 600 mg/kg MgSO4 (n = 12). The experiment started on day 90 of gestation and continued through day 21 of lactation. Blood samples were collected on day 107 of gestation, day 0 (farrowing) and 21 (weaning) of lactation for the analyses of the blood biochemistry parameters and immunoglobulin levels. The colostrum and milk samples were obtained on day 0 and 14 of lactation, respectively. Fecal samples were collected from the sows on day 107 of gestation as well as day 7 and 20 of lactation to determine fecal moisture content. The results showed that the survival percentage of piglets and the litter weight at weaning were decreased linearly (p<0.05) and other parameters of the sow or litter performance were not influenced (p>0.05) by MgSO4 supplementation. The fecal moisture content of the sows were increased (p<0.05) linearly as dietary MgSO4 increased on day 7 and 20 of lactation. Supplementation with MgSO4 increased the plasma magnesium (Mg) level linearly (p<0.05) and had a trend to increase total protein level (p>0.05 and p<0.10). However, an increase in the dietary MgSO4 level resulted in a linear decrease in the colostrum fat content (p<0.05). Dietary MgSO4 supplementation enhanced the immunoglobulin G (IgG) level (linear, p<0.05) in plasma on day of farrowing and immunoglobulin A (IgA) level in colostrum (quadratic, p<0.05) and milk (linear, p<0.05) of the sows. These results indicated that supplementation with MgSO4 during late gestation and lactation may have the potential to prevent sow constipation, but may also result in some negative effects.
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Functional characterization of the Ginkgo biloba chalcone synthase gene promoter in transgenic tobacco. GENETICS AND MOLECULAR RESEARCH 2014; 13:3446-60. [PMID: 24841790 DOI: 10.4238/2014.april.30.6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The regulative sequence (2273 bp) of the chalcone synthase gene promoter of biloba was cloned by genomic walking. A 2273-bp promoter 5' upstream translation start site of GbCHS was cloned and designated as GbCHSP. pBI121+CHSP:GUS and pBI121-35S:GUS were constructed and transformed into tobacco by LBA4404. We found that GbCHSP could drive transient expression of GUS in tobacco and differentially expressed in root, stem and leaf tissues of this plant. GUS activity regulated by the CHSP promoter were located in tissues (apical meristems) at the growing points of roots and stems. pBI121+CHSP:GUS could be induced by wounding, copper, UV-B, abscisic acid, and ethephon treatments of transgenic seedlings. This activity was weakly inhibited by gibberellin. Deletion analysis of the CHSP promoter in transgenic tobacco showed that CHSP1 complete promoter conferred a GUS expression and activity similar to that of 35 S(CaMV). GUS activity dropped dramatically when there were CHSP4, CHSP5 constructs and was almost totally absent when the CHSP6 construct was present. We conclude that the upstream sequence -1548 to -306 of GbCHSP is the main region for transcriptional regulation of the CHS gene and that it is activated by hormone and stress factors in G. biloba. These results will help us to understand the transcriptional regulatory mechanisms involved in GbCHS expression and flavonoid accumulation in G. biloba.
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Effectiveness of maifanite in reducing the detrimental effects of cadmium on growth performance, cadmium residue, hematological parameters, serum biochemistry, and the activities of antioxidant enzymes in pigs. Biol Trace Elem Res 2013; 155:49-55. [PMID: 23904328 DOI: 10.1007/s12011-013-9769-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 07/22/2013] [Indexed: 10/26/2022]
Abstract
This study was conducted to investigate the toxicity of cadmium and to evaluate the effectiveness of maifanite in preventing cadmium-induced adverse effects. Thirty-two crossbred pigs (Duroc × Landrace × Large white, sex balanced, 17.25 ± 0.07 kg average body weight) were randomly allotted to one of four dietary treatments in a 2 × 2 factorial arrangement, with eight replicates per treatment and one pig per replicate. The dietary treatments included two cadmium (as CdCl2) doses (0.32 and 30.49 mg/kg) and two maifanite doses (0 and 1%). The results showed that pigs treated with cadmium decreased their average daily feed intake (P < 0.05) and increased (P < 0.05) the feed/gain ratio. Cadmium was found in the tissues of pigs that were fed with cadmium-contaminated diets, but the level of cadmium was much lower when maifanite was added to the cadmium-contaminated diets. Ingestion of diets that were artificially contaminated with cadmium (30.49 mg/kg of cadmium) reduced (P < 0.05) the number of lymphocytes, the total erythrocyte count, the hemoglobin level, and the hematocrit. However, the activities of serum aspartate aminotransferase and gamma glutamyltransferase were increased (P < 0.05). The total protein level was lower (P < 0.05) in pigs fed with cadmium-contaminated diets. The contents of malondialdehyde increased (P < 0.05), while the total antioxidant capacity and the activities of total superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and catalase decreased (P < 0.05) in pigs fed with cadmium-contaminated diets. Dietary addition of maifanite can, to some extent, prevent the negative effects associated with feeding cadmium diets (30.49 mg/kg of cadmium) to pigs.
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Molecular cloning and characterization of GbDXS and GbGGPPS gene promoters from Ginkgo biloba. GENETICS AND MOLECULAR RESEARCH 2013; 12:293-301. [PMID: 23408416 DOI: 10.4238/2013.february.4.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ginkgolides are key pharmaceutical components in Ginkgo biloba leaves. 1-Deoxy-D-xylulose-5-phosphate synthase (GbDXS) and geranylgeranyl pyrophosphate (GbGGPPS) genes are critical genes involved in ginkgolide biosynthesis. In this study, the promoters of GbDXS and GGPPS, with 676 and 570 bp in length, respectively, were cloned by chromosome walking. The cis-elements of GbDXS and GbGGPPS promoters were predicted and analyzed by the plant cis-acting regulatory element (CARE) database. We found some major cis-elements in the sequence of GbDXS and GbGGPPS promoters. The GbDXS promoter has 3 TATA boxes, 10 CAAT boxes, 6 GATA boxes, and 1 I box. The GbGGPPS promoter has 1 TATA box, 6 CAAT boxes, 6 GATA boxes, and 4 I boxes. Furthermore, some stress-related cis-elements in the promoters of GbDXS and GbGGPPS were found to be light-regulated elements, including sequences over-represented in light-induced promoters (SORLIP1- AT), GATA box, and I box, a gibberellin-responsive element (WRKY), salicylic acid-induced (GT-1), cold- and dehydration-responsive (MYC-Core), and copper-inducible (CURE-Core). Further analyses of these cis-elements will aid in elucidating the molecular mechanisms regulating the expression of the GbDXS and GbGGPPS genes during ginkgolide accumulation in G. biloba.
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Changes in first hip fracture rates in British Columbia Canada, 1990-2004. Osteoporos Int 2011; 22:2817-27. [PMID: 21305269 DOI: 10.1007/s00198-010-1488-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022]
Abstract
UNLABELLED We determined age-standardized first hip fracture rates in British Columbia between 1990 and 2004. We found sex and fracture type rates in keeping with previous reports and that fracture rates have decreased approximately 18% overall in both men and women. INTRODUCTION To determine whether there have been changes in the age-, sex-, and subtype-specific first hip fracture rates in Canadian province of British Columbia (BC) between 1990 and 2004. METHODS Records of all persons aged 60 years and older hospitalized with hip fractures in BC between 1985 and 2004 were obtained from the Canadian Institute for Health Information Discharge Abstract Database. Only the first hip fracture records were included, and fractures likely due to causes other than trauma were excluded. Age- and sex-specific rates were calculated using population denominators from Statistics Canada and direct standardization was used. Age-standardized rates allowed for comparison across years with adjustment for age distribution. RESULTS There were 41,990 records of first hip fracture included, and 73% were in women. Trends in age-specific rates by fracture type were similar to previous reports. Between 1990 and 2004, there has been an age-adjusted 18% decrease in first hip fracture rates in women, and 19% decrease in first hip fracture rates in men. The decrease was statistically significant in femoral neck fractures in women, but not in men. CONCLUSIONS There has been a decrease in age-adjusted hip fracture rates in BC between 1990 and 2004, which is in contrast to previous projections for hip fracture rates in Canada.
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Geographic trends in incidence of hip fractures: a comprehensive literature review. Osteoporos Int 2011; 22:2575-86. [PMID: 21484361 DOI: 10.1007/s00198-011-1596-z] [Citation(s) in RCA: 160] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 02/14/2011] [Indexed: 12/18/2022]
Abstract
UNLABELLED A comprehensive review of literature was conducted to investigate variation in hip fracture incident rates around the world. The original crude incidence rates were standardized for age and sex for comparability. After standardization, the highest rates of hip fracture were found in Scandinavia and the lowest rates in Africa. INTRODUCTION This study was conducted to investigate the geographic trends of the incidence of osteoporotic hip fractures through a comprehensive review of literature. METHODS Studies were identified for inclusion in the review by searching the MEDLINE database via PubMed and applying strict inclusion and exclusion criteria. Age-specific incidence rates were extracted from the articles, and in order to provide a common platform for analysis, we used directly age-standardized and age-sex-standardized rates (using the 2005 United Nations estimates of the world population as standard) to complete the analysis. RESULTS Forty-six full text articles spanning 33 countries/regions were included in the review. For ease of comparison, the results were analyzed by geographic regions: North America, Latin America, Scandinavia, Europe (excluding Scandinavia), Africa, Asia, and Australia. The highest hip fracture rates were found in Scandinavia and the lowest in Africa. We found comparable rates from countries in North America, Australia, and Europe outside of Scandinavia. The diverse makeup of the Asian continent also resulted in quite variable hip fracture rates: ranging from relatively high rates in Iran to low rates, comparable to those from Africa, in mainland China. CONCLUSIONS Given the aging of populations globally, and in the industrialized countries specifically, hip fractures will become a progressively larger public health burden. The geographic trends observed in hip fracture incidence rates can provide important clues to etiology and prevention.
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Play fighting and corticotropin-releasing hormone in the lateral septum of golden hamsters. Neuroscience 2010; 169:236-45. [PMID: 20417693 DOI: 10.1016/j.neuroscience.2010.04.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 04/01/2010] [Accepted: 04/19/2010] [Indexed: 11/19/2022]
Abstract
This study was focused on determining the possible role of corticotropin-releasing hormone (CRH) on play fighting in juvenile golden hamsters. As no specific neural sites have been proposed, we looked for changes in CRH innervations at the peak of play-fighting activity on postnatal day 35 (P-35) from a week before on P-28. We noted that the increase in play-fighting activity between these two dates was associated with a 100% increase of the density of CRH fibers within the lateral septum. We, then, tested the possible role of CRH receptors on play fighting within the lateral septum through microinjections of alpha-helical CRH, a CRH receptor antagonist (either 0, 30, or 300 ng), directly into the area. The treatments inhibited play-fighting attacks and pins as well as reduced the duration of time that the resident hamsters spent in contact with the intruders, though locomotor activity remained unaffected. The possible source of CRH release in the lateral septum was addressed by quantification of CRH neurons also labeled with a marker of cellular activity, c-Fos, after consummation of play fighting. CRH neurons in the horizontal part of the diagonal band, an area reciprocally connected with the lateral septum, showed a 75% increase in double labeling with c-Fos as compared to controls. Together, these data show that CRH receptors in the lateral septum have a general role on play fighting, not just facilitating its consummation, but also likely enhancing appetitive aspects as well. In addition, this effect is associated with enhanced CRH availability in the area and enhanced neuronal activity within interconnected areas.
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CALHM1 variant is not associated with Alzheimer's disease among Asians. Neurobiol Aging 2009; 32:546.e11-2. [PMID: 19545933 DOI: 10.1016/j.neurobiolaging.2009.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 05/05/2009] [Accepted: 05/11/2009] [Indexed: 11/27/2022]
Abstract
In a case control study involving 484 study subjects, we showed that the CALHM1 allele (13.5% vs 16.7%) and genotype frequency was not significantly different between Alzheimer's disease (AD) and controls. Logistic regression analysis did not reveal any interaction between ApoE4 allele and CALHM1 allele.
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Distinct dysregulation of lipid metabolism by unliganded thyroid hormone receptor isoforms. Mol Endocrinol 2009; 23:308-15. [PMID: 19131509 DOI: 10.1210/me.2008-0311] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Thyroid hormone receptors (TRs) play critical roles in energy homeostasis. To understand the role of TRs in lipid homeostasis in vivo, we adopted the loss-of-function approach by creating knock-in mutant mice with targeted mutation in the TRalpha gene (TRalpha1PV mouse) or TRbeta gene (TRbetaPV mouse). The PV mutation, identified in a patient with resistance to thyroid hormone, exhibits potent dominant-negative activity. Here we show that in contrast to TRalpha1PV mouse, TRbetaPV mice exhibited no significant reduction in WAT but had significant increases in serum free fatty acids and total triglycerides. Moreover, the liver of TRbetaPV mice was markedly increased (33%) with excess lipid accumulation, but the liver mass of TRalpha1PV mouse was decreased (23%) with paucity of lipids. These results indicate that apo-TRbeta and apo-TRalpha1 exerted distinct abnormalities in lipid metabolism. Further biochemical analyses indicate that increased lipogenic enzyme expression, activated peroxisome proliferator-activated receptor gamma (Ppargamma) signaling, and decreased fatty acid beta-oxidation activity contributed to the adipogenic steatosis and lipid accumulation in the liver of TRbetaPV mice. In contrast, the expression of lipogenic enzymes and Ppargamma was decreased in the liver of TRalpha1PV mice. These results suggest that the regulation of genes critical for lipid metabolism by TRs in the liver is isoform dependent. These results indicate that apo-TRbeta and apo-TRalpha1 had different effects on lipid metabolism and that both TR isoforms contribute to the pathogenesis of lipid metabolism in hypothyroidism.
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Hedgehog signaling promotes the degradation of tumor suppressor Sufu through the ubiquitin-proteasome pathway. Oncogene 2008; 28:492-9. [PMID: 18997815 DOI: 10.1038/onc.2008.403] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Sustained Sonic hedgehog (Shh) pathway activity is associated with tumorigenesis in a wide variety of tissues. Mutational inactivation of Shh receptor Patched (Ptch) and a downstream gene Suppressor of fused (Sufu), both of which are negative regulators of the pathway, increases susceptibility to cerebellum cancer in humans and mice. Sufu is a binding partner of Shh pathway transcription factor Gli. Recent data indicate that inactivation of Sufu, through either gene targeting in mice or RNAi-mediated silencing in cultured fibroblasts, is sufficient to turn on Shh target gene expression. Here, we report that Sufu is degraded rapidly in certain cancer cells and we show that Shh signaling promotes ubiquitination of Sufu, which leads to its destruction in the proteasomes. We identified an ubiquitin attachment site on K257 of Sufu, and showed that Sufu-K257R mutant is more potent as a transcription repressor and cell growth inhibitor because of increased stability. These results indicate that Shh signaling regulates Sufu activity by inducing its turnover via the ubiquitin-proteasome system.
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Abstract
OBJECTIVES Over half of all terminal cancer patients in Taiwan are 65 or older, thus demonstrating the importance of terminal care for elderly people. This study investigates the good death status of elderly patients with terminal cancer, comparing the differences in the degree of good death among elderly and younger groups, and exploring the factors related to the good death score. METHODS Three hundred and sixty-six patients with terminal cancer admitted to a palliative care unit were enrolled. Two structured measurements, the good death scale and the audit scale for good death services, were used as the instruments in the study. RESULTS The scores of individual items and of the good death scale were increased significantly in both elderly (n = 206, 56.3%) and younger (n = 160, 43.7%) groups from the time of admission to just prior to death. However, the elderly group had significantly lower scores in 'awareness' (t = -3.76, P < 0.001), 'propriety' (t = -2.92, P < 0.01) and 'timeliness' (t = -2.91, P < 0.01) than the younger group prior to death. Furthermore, because of a lack of truth-telling, the elderly group also had significantly lower scores than the younger group in both 'respect for autonomy' and 'decision-making participation' (t = -2.17, P < 0.05; t = -2.21, P < 0.05, respectively). Multiple regression analysis revealed that 'respect for autonomy' (OR = 1.22, 95% CI = 0.76-1.67) and 'verbal support '(OR = 0.93, 95% CI = 0.34-1.51) were two independent correlates of the good death score in the elderly group. CONCLUSION The dilemma of truth-telling compromises the autonomy of the elderly patients with terminal cancer and consequently affects their good death scores. The palliative care team should emphasize the issue of truth-telling in the process of caring for terminally ill cancer patients, especially elderly patients.
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Abstract
The key mitotic regulator securin is expressed at low levels in fetal brain compared with adult, and modulates the proliferation of human embryonic neuronal N-Tera2 (NT2) cells. We now examine the function and expression of securin's interacting partner separase, along with Rad21, the functional component of cohesin, which is cleaved by separase following interaction with securin. In contrast to securin, the cleaved forms of separase and Rad21 were highly expressed in human fetal cerebral cortex compared with adult. In a murine model of absent securin expression - the PTTG knock-out mouse - separase and Rad21 were over-expressed in multiple brain regions. In addition, cDNA array analysis of other key mitotic regulators additionally identified cyclin C and sestrin 2 to be induced in the brains of securin-null mice compared with wild type. Further, Rad21 mRNA expression was highly correlated with that of securin, separase, cyclin C and sestrin 2 in fetal brains. In embryonic neuronal NT2 cells, siRNA repression of separase failed to significantly alter cell turnover, whereas repression of securin expression resulted in increased levels of the activated forms of Rad21 and separase, and promoted cell proliferation. Our data suggest that the co-ordinated expression of separase, securin and Rad21 is fundamental for the developing brain.
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Effect of microwave annealing temperatures on lead zirconate titanate thin films. NANOTECHNOLOGY 2007; 18:395704. [PMID: 21730429 DOI: 10.1088/0957-4484/18/39/395704] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Lead zirconate titanate (Pb(1.1)(Zr(0.52)Ti(0.48))O(3)) thin films of thickness 260 nm on Pt/Ti/SiO(2)/Si substrates were densified by 2.45 GHz microwave annealing. The PZT thin films were annealed at various annealing temperatures from 400 to 700 °C for 30 min. X-ray diffraction showed that the pyrochlore phase was transformed to the perovskite phase at 450 °C and the film was fully crystallized. The secondary (again pyrochlore) phase was observed in the PZT thin films, which were annealed above 550 °C. The surface morphologies were changed above 550 °C of the PZT thin films due to the secondary phase. Higher dielectric constant (ε(r)) and lower dielectric loss coercive field (E(c)) were achieved for the 450 °C film than for the other annealed films.
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SU-FF-I-89: Effects of EPI Slice Angle, Slice Thickness and Phase Encoding Direction On FMRI Sensitivity in Areas with Susceptibility Artifact. Med Phys 2007. [DOI: 10.1118/1.2760466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Abstract
BACKGROUND The development of a knockin mouse model of resistance to thyroid hormone (RTH) has led to a greater understanding of both the molecular and clinical behaviour of this syndrome. We have investigated the vascular response in RTH using a specific (TRbeta PV) knockin mouse model targeting the PV mutation to the thyroid hormone receptor beta gene locus. MATERIALS AND METHODS Ring segments of the thoracic aorta were used to assess the response of homozygous, heterozygous and wild-type controls to contractile agents, potassium chloride and phenylephrine. Each genotype after maximal contraction was exposed to increasing concentrations of relaxing agents, acetylcholine (ACh) and sodium nitroprusside (SNP). RESULTS The response of these aortic ring segments to ACh and SNP demonstrates that endothelium-dependent relaxation to ACh was significantly impaired in both heterozygous and homozygous mice compared to controls (69.8 +/- 2.0%, 59.7 +/- 1.4% and 75.0 +/- 1.7%, respectively; P < 0.001). However, endothelium independent responses to SNP showed no difference between genotypes (114.4 +/- 3.2%, 116.8 +/- 2.6% and 106.9 +/- 4.9%; P = NS). CONCLUSION These data suggest that endothelial function is impaired in the RTH mouse aorta. The respective roles of elevated thyroid stimulating hormone (TSH), elevated thyroid hormone concentrations and the mutated thyroid hormone beta receptor require further elucidation.
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Neuropilin-1 promotes human glioma progression through potentiating the activity of the HGF/SF autocrine pathway. Oncogene 2007; 26:5577-86. [PMID: 17369861 PMCID: PMC2846324 DOI: 10.1038/sj.onc.1210348] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Neuropilin-1 (NRP1) functions as a coreceptor through interaction with plexin A1 or vascular endothelial growth factor (VEGF) receptor during neuronal development and angiogenesis. NRP1 potentiates the signaling pathways stimulated by semaphorin 3A and VEGF-A in neuronal and endothelial cells, respectively. In this study, we investigate the role of tumor cell-expressed NRP1 in glioma progression. Analyses of human glioma specimens (WHO grade I-IV tumors) revealed a significant correlation of NRP1 expression with glioma progression. In tumor xenografts, overexpression of NRP1 by U87MG gliomas strongly promoted tumor growth and angiogenesis. Overexpression of NRP1 by U87MG cells stimulated cell survival through the enhancement of autocrine hepatocyte growth factor/scatter factor (HGF/SF)/c-Met signaling. NRP1 not only potentiated the activity of endogenous HGF/SF on glioma cell survival but also enhanced HGF/SF-promoted cell proliferation. Inhibition of HGF/SF, c-Met and NRP1 abrogated NRP1-potentiated autocrine HGF/SF stimulation. Furthermore, increased phosphorylation of c-Met correlated with glioma progression in human glioma biopsies in which NRP1 is upregulated and in U87MG NRP1-overexpressing tumors. Together, these data suggest that tumor cell-expressed NRP1 promotes glioma progression through potentiating the activity of the HGF/SF autocrine c-Met signaling pathway, in addition to enhancing angiogenesis, suggesting a novel mechanism of NRP1 in promoting human glioma progression.
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MESH Headings
- Animals
- Butadienes/pharmacology
- Cell Line
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Disease Progression
- Enzyme Inhibitors/pharmacology
- Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Gene Expression Regulation, Neoplastic
- Glioma/genetics
- Glioma/metabolism
- Glioma/pathology
- Hepatocyte Growth Factor/pharmacology
- Hepatocyte Growth Factor/physiology
- Humans
- Immunoblotting
- Mice
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/pathology
- Neovascularization, Pathologic/genetics
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- Neuropilin-1/genetics
- Neuropilin-1/metabolism
- Neuropilin-1/physiology
- Nitriles/pharmacology
- Phosphorylation/drug effects
- Proto-Oncogene Proteins c-met/physiology
- RNA, Small Interfering/genetics
- Signal Transduction/physiology
- Transfection
- Transplantation, Heterologous
- Tumor Burden
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The induction of amyloid precursor protein and α-synuclein in rat hippocampal astrocytes by diethyldithiocarbamate and copper with or without glutathione. Toxicol Lett 2004; 146:139-49. [PMID: 14643966 DOI: 10.1016/j.toxlet.2003.09.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
alpha-Synuclein is the major component of Lewy bodies. Its aggregation can be accelerated by copper, iron, or beta-amyloid (Abeta) and has been thought to provide a nucleation center during the formation of amyloid plaques. The main structural component of amyloid plaque is Abeta, which is derived from a larger protein, amyloid precursor protein (APP). Xenobiotics have been implicated in the etiology of the neurodegenerative disease. Mechanisms of diethyldithiocarbamate (DDC) neurotoxicity involve copper chelation and interactions with SH groups resulting in oxidative stress. In this study, rat hippocampal astrocytes were treated with DDC (75 microM), CuCl(2) (0.2 microM), or DDC (75 microM) plus CuCl(2) (0.2 microM) for 1h. Cells were allowed to recover with or without 10 mM GSH. Results showed an increase of APP and alpha-synuclein production occurring in a time-dependent manner. At 4 h post-treatment, cells contained small positively stained material deposited throughout the cytosol for APP and by 8 h post-treatment increases were seen in both APP and alpha-synuclein. Immunoblots supported immunocytochemical results. Glutathione (GSH) decreased the accumulation of these proteins at 8 h post-treatment.
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An integrated subsurface modeling and risk assessment approach for managing the petroleum-contaminated sites. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2004; 39:3083-3113. [PMID: 15533023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Soil and groundwater contamination can lead to a variety of impacts and risks to the communities. Identifications of management schemes with sound environmental and socio-economic efficiencies is desired. In fact, before any decisions regarding site remediation actions can be made, three major questions may have to be answered. They include "What happened underground, and what will happen in the future under the given remediation scenarios?," "Are there specific risks on the surrounding community?" and "What remediation alternatives are suitable for the site?" In this study, an integrated subsurface modeling and risk assessment method for petroleum-contaminated site management is proposed. It incorporates multi-phase flow multi-component transport modeling and ELCR-based human health risk assessment into a general framework. The proposed method is applied to a case study within a western Canada context for identifying effective management schemes with improved environmental and socio-economic efficiencies. Given conditions at the study site, six remediation alternatives based on combinations of several technologies are recommended, with the provision of analyses for equipment/manpower requirements, system designs, operations, efficiencies, and costs. These alternatives can be categorized into two groups: hybrid ex situ and in situ remediation approaches, and integrated in situ remediation approaches. This study is a new attempt that integrates issues of subsurface-contamination simulation, risk assessment, and site remediation for a real-world problem within a general research framework. The research outputs are directly useful for the industry to gain insight of the site and to make decisions of the relevant remediation actions.
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Effect of addition of sodium hydroxide and calcium nitrate on polycyclic aromatic hydrocarbon emission from benzene incineration. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003; 71:675-681. [PMID: 14672118 DOI: 10.1007/s00128-003-0186-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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Abstract
Thyroid hormone plays important roles in metabolism, growth, and differentiation. Germline mutations in thyroid hormone receptor beta (TRbeta) have been identified in many individuals with resistance to thyroid hormone (RTH), a syndrome of hyposensitivity to T3. However, it has become increasingly apparent that somatic mutations can also occur in individual tissues, and are associated with tumors and malignancies in man. Herein we review the occurrence and identification of germline and somatic TR mutations and characterization of their pathological effects on hormone resistance and tumorigenesis.
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Estimation of atmospheric mixing heights over large areas using data from airport meteorological stations. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2002; 37:991-1007. [PMID: 12090288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
For this study, ground and sounding meteorological data at 16 airports were used for estimating the atmospheric mixing heights in Hebei Province of China, including Beijing and Tanjing areas. Three methods were compared for this purpose, which are the dry adiabatic method, the conventional Nozaki model, and a modified Nozaki model. The feasibility of using airport meteorological data to determine mixing heights in large area was verified through the use of measured mixing heights and observed SO2 vertical profiles. The study not only estimated the mixing heights over large areas but also compared different early morning sounding temperature profiles to identify feasibility of using 2:00 a.m. sounding profiles to estimate mixing height by the dry adiabatic method. The paper also described the mixing heights over different areas such as mountain, sea boundary and plain areas. The results have considerable significance for air quality prediction and environmental management. A novel approach to estimation of atmospheric mixing heights over large area is introduced, requiring only the input of readily available airport meteorological data.
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ESTIMATION OF ATMOSPHERIC MIXING HEIGHTS OVER LARGE AREAS USING DATA FROM AIRPORT METEOROLOGICAL STATIONS. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2002; 37:991-1007. [PMID: 28880802 DOI: 10.1081/ese-120004518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
For this study, ground and sounding meteorological data at 16 airports were used for estimating the atmospheric mixing heights in Hebei Province of China, including Beijing and Tanjing areas. Three methods were compared for this purpose, which are the dry adiabatic method, the conventional Nozaki model, and a modified Nozaki model. The feasibility of using airport meteorological data to determine mixing heights in large area was verified through the use of measured mixing heights and observed SO2 vertical profiles. The study not only estimated the mixing heights over large areas but also compared different early morning sounding temperature profiles to identify feasibility of using 2:00 a.m. sounding profiles to estimate mixing height by the dry adiabatic method. The paper also described the mixing heights over different areas such as mountain, sea boundary and plain areas. The results have considerable significance for air quality prediction and environmental management. A novel approach to estimation of atmospheric mixing heights over large area is introduced, requiring only the input of readily available airport meteorological data.
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An isoform of branched-chain aminotransferase is a novel co-repressor for thyroid hormone nuclear receptors. J Biol Chem 2001; 276:48196-205. [PMID: 11574535 DOI: 10.1074/jbc.m104320200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The functions of thyroid hormone receptors (TRs) are regulated by a host of co-regulatory proteins. Tissue-specific expression of these co-regulators leads to distinct expression patterns and regulation of thyroid hormone (T3) target genes in tissues. Previously we have found that human colon carcinoma RKO cells exhibit strong T3-independent transcriptional activity. We therefore searched for co-regulatory proteins in RKO cells using a yeast two-hybrid system with the intact TRbeta1 as bait. One of the three positive clones, designated as P3, was identified to be an isoform of human mitochondria branched-chain aminotransferase (BCATm). P3 was a spliced variant of BCATm with an internal 12-amino acid deletion near the carboxyl-terminal region and was abundantly expressed in RKO cells. The expressed protein localized both to the mitochondria and the nucleus of transfected CV1 cells. P3 physically interacted with TRbeta1 in a T3-independent manner that led to the inhibition in binding of TRbeta1 to thyroid hormone-responsive element. P3 not only enhanced the repressor activity of the unliganded TR but also repressed the ligand-dependent activation of TR. This repression was reversed by treatment of cells with trichostatin A, suggesting that in addition to the inhibition of DNA binding, the repression activity of P3 on TR may also be mediated by histone deacetylase activity. Thus, unlike the currently known co-repressors, P3 is a novel ligand-independent co-repressor for TR.
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Vascular endothelial growth factor isoforms display distinct activities in promoting tumor angiogenesis at different anatomic sites. Cancer Res 2001; 61:8569-77. [PMID: 11731444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The gene for the major angiogenic factor, vascular endothelial growth factor (VEGF), encodes several spliced isoforms. We reported previously that overexpression of two VEGF isoforms, VEGF(121) and VEGF(165), by human glioma U87 MG cells induced tumor-associated intracerebral hemorrhage, whereas expression of a third form, VEGF(189), did not cause vessel rupture. Here, we test whether these VEGF isoforms have distinct activities for enhancing vascularization and growth of gliomas in mice. U87 MG cells that overexpressed VEGF(165) or VEGF(189) grew more rapidly than the parental cells in both s.c. and intracranial (i.c.) locations. However, cells that overexpressed VEGF(121) only showed enhancement of i.c. tumor growth but had a minimal effect on s.c. glioma progression. At both anatomical sties, VEGF(165) and VEGF(189) strongly augmented neovascularization, whereas VEGF(121) only increased vessel density in brain tumors. In each type of glioma, expression of VEGF receptors -1 and -2 largely phenocopied the tumor vasculature, because increased VEGF/VEGF receptor-activated microvessel densities were strongly correlated with the angiogenicity and tumorigenicity elicited by the VEGF isoforms at both anatomical sites. One notable difference between the sites was the expression of vitronectin, a prototypic ligand of alpha(v)beta(3) and alpha(v)beta(5) integrins, detected in i.c. but not in s.c., gliomas. Endothelial cell migration stimulated by VEGF(121) was potentiated by vitronectin to a greater extent than that stimulated by VEGF(165). This data demonstrates that VEGF isoforms have distinct activities at different anatomical sites and suggest that the microenvironment of different tissues affects the function of VEGF isoforms.
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Silencing of Wnt signaling and activation of multiple metabolic pathways in response to thyroid hormone-stimulated cell proliferation. Mol Cell Biol 2001; 21:6626-39. [PMID: 11533250 PMCID: PMC99808 DOI: 10.1128/mcb.21.19.6626-6639.2001] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
To investigate the transcriptional program underlying thyroid hormone (T3)-induced cell proliferation, cDNA microarrays were used to survey the temporal expression profiles of 4,400 genes. Of 358 responsive genes identified, 88% had not previously been reported to be transcriptionally or functionally modulated by T3. Partitioning the genes into functional classes revealed the activation of multiple pathways, including glucose metabolism, biosynthesis, transcriptional regulation, protein degradation, and detoxification in T3-induced cell proliferation. Clustering the genes by temporal expression patterns provided further insight into the dynamics of T3 response pathways. Of particular significance was the finding that T3 rapidly repressed the expression of key regulators of the Wnt signaling pathway and suppressed the transcriptional downstream elements of the beta-catenin-T-cell factor complex. This was confirmed biochemically, as beta-catenin protein levels also decreased, leading to a decrease in the transcriptional activity of a beta-catenin-responsive promoter. These results indicate that T3-induced cell proliferation is accompanied by a complex coordinated transcriptional reprogramming of many genes in different pathways and that early silencing of the Wnt pathway may be critical to this event.
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Brain glucose utilization in mice with a targeted mutation in the thyroid hormone alpha or beta receptor gene. Proc Natl Acad Sci U S A 2001; 98:9913-8. [PMID: 11481455 PMCID: PMC55552 DOI: 10.1073/pnas.171319498] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2001] [Indexed: 11/18/2022] Open
Abstract
Brain glucose utilization is markedly depressed in adult rats made cretinous after birth. To ascertain which subtype of thyroid hormone (TH) receptors, TRalpha1 or TRbeta, is involved in the regulation of glucose utilization during brain development, we used the 2-[(14)C]deoxyglucose method in mice with a mutation in either their TRalpha or TRbeta gene. A C insertion produced a frameshift mutation in their carboxyl terminus. These mutants lacked TH binding and transactivation activities and exhibited potent dominant negative activity. Glucose utilization in the homozygous TRbetaPV mutant mice and their wild-type siblings was almost identical in 19 brain regions, whereas it was markedly reduced in all brain regions of the heterozygous TRalpha1PV mice. These suggest that the alpha1 receptor mediates the TH effects in brain. Inasmuch as local cerebral glucose utilization is closely related to local synaptic activity, we also examined which thyroid hormone receptor is involved in the expression of synaptotagmin-related gene 1 (Srg1), a TH-positively regulated gene involved in the formation and function of synapses [Thompson, C. C. (1996) J. Neurosci. 16, 7832-7840]. Northern analysis showed that Srg1 expression was markedly reduced in the cerebellum of TRalpha(PV/+) mice but not TRbeta(PV/PV) mice. These results show that the same receptor, TRalpha1, is involved in the regulation by TH of both glucose utilization and Srg1 expression.
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Abstract
This study assessed sedation in terminal cancer patients in terms of three characteristics: frequency; relationship to intractable symptoms; and the extent to which medical staff, family, and patients found sedation to be ethically acceptable and efficacious. Two hundred seventy-six consecutive patients, who were admitted to the palliative care unit of National Taiwan University Hospital in Taiwan between August 1998 and the end of May 1999, were enrolled. A recording form was completed every day. This included demographic data, pain and common symptom scores, and the use of sedation in the terminal phase. Seventy (27.9%) of 251 patients who died received sedation. Sedation was administered to relieve agitated delirium in 40 (57.1%), dyspnea in 16 (22.8%), severe pain in 7 (10%) and insomnia in 5 (7.2%). The drugs used for sedation were haloperidol in 35 (50%), midazolam in 17 (24.3%), and rapidly increasing dosage of morphine in 9 (12.9%). In fewer than half (42.9%) of the patients, sedation was with the consent of both patient and family, and half (50%) had the consent of family alone. The overwhelming majority of medical staff and family felt the decision to use terminal sedation was ethically acceptable. There was no significant difference in survival time between sedated and non-sedated patients (28.49 vs. 24.71 days, t = -0.791, P = 0.430). Positive ethical acceptability and higher satisfaction with symptom control with terminal sedation were found in both medical staff and family in this study. Further work is needed to find the most appropriate time of intervention and to improve management of refractory symptoms in dying patients.
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Pancreatic cancer cell-derived vascular endothelial growth factor is biologically active in vitro and enhances tumorigenicity in vivo. Int J Cancer 2001; 92:361-9. [PMID: 11291072 DOI: 10.1002/ijc.1202] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Vascular endothelial growth factor (VEGF) is a potent angiogenic stimulator that acts by binding to high-affinity transmembrane receptors. Although both VEGF and its receptors are overexpressed in human pancreatic ductal adenocarcinoma (PDAC), this malignancy is not generally considered to be highly vascular. It is not known, therefore, whether the abundance of VEGF in PDAC is biologically relevant. To address this issue, we measured the angiogenic effects of pancreatic cancer cell-derived VEGF in an in vitro endothelial cell proliferation assay and characterized the consequences of suppressing VEGF expression on pancreatic tumor growth in an athymic nude mouse model. We found that human pancreatic cancer cell lines secrete large quantities of biologically active VEGF into conditioned medium (CM). Stable transfection of an anti-sense VEGF(189) (AS-VEGF(189)) expression construct into PANC-1 pancreatic cancer cells resulted in decreased VEGF expression and secretion, a decreased capacity of the resultant CM to enhance endothelial cell proliferation and a significant attenuation of tumor cell proliferation in vitro. Furthermore, when injected into athymic nude mice, AS-VEGF(189)-expressing cells exhibited an 80% decrease in tumor growth compared with control cells. These results support the hypothesis that VEGF promotes pancreatic cancer growth in vivo and suggest that anti-VEGF therapy may be useful in the treatment of this disease.
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Special features of non-melanoma skin cancer in Hong Kong Chinese patients: 10-year retrospective study. Hong Kong Med J 2001; 7:22-8. [PMID: 11406672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
OBJECTIVE To determine the incidence and clinical characteristics of non-melanoma skin cancer in Hong Kong Chinese patients. DESIGN Retrospective study. SETTING Social Hygiene Services, Hong Kong. PATIENTS Records of 528 Chinese patients with a histological diagnosis of non-melanoma skin cancer from 1990 to 1999 were reviewed. MAIN OUTCOME MEASURES Demographic data, site and clinical type of cancer, predisposing factors, history, recurrence, and the development of new skin cancers. RESULTS Non-melanoma skin cancer is uncommon but not rare among the Chinese population in Hong Kong. The incidence of newly diagnosed basal cell carcinoma in 1990 was 16.0 per 10,000 new skin case attendances and, in 1999, the incidence was 31.8 per 10,000 new skin case attendances. The corresponding figures for squamous cell carcinoma in 1990 and 1999 were 6.9 and 11.6 per 10,000 new skin case attendances. The incidence of basal cell carcinoma among the Hong Kong Chinese population in 1990 and 1999 was 0.32 and 0.92 per 100,000, respectively, whereas that of squamous cell carcinoma was 0.16 and 0.34 per 100,000, respectively. Demographic data and the site distribution of non-melanoma skin cancer were comparable to those reported in Caucasians living in North America and Europe, but different from those in Caucasians living in Australia and Hawaii. Pigmented basal cell carcinoma was the most common type of non-melanoma skin cancer (60.1%) in Chinese patients, in contrast with rodent ulceration in Caucasian. Multiple skin cancers, recurrence, and subsequent new skin cancers were less frequently observed than in studies of Caucasians. CONCLUSION When compared with reported findings in Caucasians, Chinese patients show differences in the clinical type and multiplicity of lesions, predisposing factors, recurrence, and subsequent new skin cancer rates for non-melanoma skin cancer. Pigmented basal cell carcinoma seems to be an important differential diagnosis with regard to pigmented lesions in the Chinese population.
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The time-course change of nitrogenous excretion in the Kuruma shrimp Penaeus japonicus following nitrite exposure. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2001; 51:443-454. [PMID: 11090902 DOI: 10.1016/s0166-445x(00)00122-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Penaeus japonicus (12.83 +/- 1.24 g) which were exposed individually to 0.002 (control), 0.076, 0.362, 0.719 and 1.433 mM nitrite at 30 ppt of salinity were examined for hemolymph ammonia, urea and nitrite, and nitrogenous excretion after 3, 6, 12, 24 and 48 h, respectively. Hemolymph nitrite and hemolymph urea increased directly with ambient nitrite and exposure time, whereas hemolymph ammonia was inversely related to ambient nitrite and exposure time. Specific excretions of total-N (total nitrogen), ammonia-N, urea-N and organic-N (organic nitrogen) increased directly with ambient nitrite and exposure time. The contribution of ammonia-N excretion and urea-N excretion in the total-N excreted by the control shrimp was 41.7-90.8 and 2.8-10.5%, respectively. The contribution of ammonia-N in the total-N excreted by P. japonicus decreased to 10.0 and 3.8%, when they were exposed for 24 h to 0.076 and 1.433 mM nitrite, respectively. The contribution of urea-N excretion increased to 58.7 and 21.4%, and the organic-N excretion increased to 31.3 and 74.8% in the total-N excreted by the shrimp following 24 h exposure to 0.076 and 1.433 mM nitrite, respectively. It was concluded that P. japonicus following 24 h exposure to nitrite as low as 0.076 mM increased its ammonia-N excretion by a factor of 1.9, its urea-N excretion by 200, and its organic-N excretion by 37, as compared to those in the control solution.
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Estimation of atmospheric mixing heights using data from airport meteorological stations. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2001; 36:521-532. [PMID: 11413836 DOI: 10.1081/ese-100103481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this study, ground and sounding meteorological data at the Beijing Airport during 1991 to 1995 were used for estimating the local atmospheric mixing heights. Three methods were compared for this purpose, including the dry adiabatic method, the Nozaki model, and a modified Nozaki model. The modification of the Nozaki model included joint frequencies for wind-velocity and stability based on the complexities of local meteorological conditions. The estimated values from the three methods were verified through the data measured by the Beijing Meteorological Center. The results indicated that the dry adiabatic method has the best performance. The modified Nozaki model was better than the commonly used. This study is a new attempt in utilizing airport meteorological data to estimate atmospheric mixing heights.
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Abstract
OBJECTIVES To investigate the incidence and solution of ethical dilemmas in a palliative care unit. DESIGN Health care workers recorded daily all dilemmas in caring for each patient. SETTING Palliative care unit of National Taiwan University Hospital in Taiwan. PATIENTS Two hundred and forty-six consecutive patients with terminal cancer during 1997-8. MAIN MEASUREMENT Ethical dilemmas in the questionnaire were categorised as follows: telling the truth; place of care; therapeutic strategy; hydration and nutrition; blood transfusion; alternative treatment; terminal sedation; use of medication, and others. RESULTS The type and frequency of ethical dilemmas encountered were: place of care (33.3%); truth-telling (32.1%); hydration and nutrition (25.2%); therapeutic strategy (24.8%), and use of medication (19.1%). Ethical problems relating to the place of care and to therapeutic strategy were unlikely to be solved with increased hospital stay and some ethical dilemmas remained unsolved even in the final week in hospital, including place of care (23.2%), truth-telling (17.1%) and therapeutic strategy (11.4%). Problems of truth-telling occurred in nearly half (42.6%) of patients over sixty-five-years-old. Conflicts about blood transfusion were experienced in all patients below 18-years-old, and the dilemmas concerning the place of care occurred most frequently with head and neck cancer patients (43.8%). CONCLUSIONS The solution of ethical dilemmas required refocusing by medical professionals on the importance of continuing communication. Improved ethical training for professionals would contribute to solving the moral dilemmas of palliative care.
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Trace elements and lipid peroxidation in human seminal plasma. Biol Trace Elem Res 2000; 76:207-15. [PMID: 11049219 DOI: 10.1385/bter:76:3:207] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/1999] [Revised: 08/18/1999] [Accepted: 11/20/1999] [Indexed: 11/11/2022]
Abstract
In the present study, the concentrations of copper, iron, zinc, and malondialdehyde in human seminal plasma were measured and correlated with the sperm count and motility in human semen. Copper, iron, and zinc were analyzed by atomic absorption spectrometry, whereas malondialdehyde was measured by high-performance liquid chromatography. The malondialdehyde concentrations in asthenospermia and oligoasthenospermia were significantly higher than in normospermia. Copper and iron levels were higher in asthenospermia, whereas the zinc concentrations in both oligospermia and asthenospermia were lower than in normal controls. A negative correlation (r = -0.28, p < 0.05) between the malondialdehyde concentration and sperm motility was observed in the abnormal groups. There was no association among copper, iron, zinc, and malondialdehyde in seminal plasma. We concluded that changes in trace elements may be related to sperm quality and that lipid peroxidation, although it is not promoted in the seminal plasma by copper or iron or ameliorated by zinc, may be involved in the loss of sperm motility.
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Repeat polymorphisms within gene regions: phenotypic and evolutionary implications. Am J Hum Genet 2000; 67:345-56. [PMID: 10889045 PMCID: PMC1287183 DOI: 10.1086/303013] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2000] [Accepted: 06/02/2000] [Indexed: 11/03/2022] Open
Abstract
We have developed an algorithm that predicted 11,265 potentially polymorphic tandem repeats within transcribed sequences. We estimate that 22% (2,207/9,717) of the annotated clusters within UniGene contain at least one potentially polymorphic locus. Our predictions were tested by allelotyping a panel of approximately 30 individuals for 5% of these regions, confirming polymorphism for more than half the loci tested. Our study indicates that tandem-repeat polymorphisms in genes are more common than is generally believed. Approximately 8% of these loci are within coding sequences and, if polymorphic, would result in frameshifts. Our catalogue of putative polymorphic repeats within transcribed sequences comprises a large set of potentially phenotypic or disease-causing loci. In addition, from the anomalous character of the repetitive sequences within unannotated clusters, we also conclude that the UniGene cluster count substantially overestimates the number of genes in the human genome. We hypothesize that polymorphisms in repeated sequences occur with some baseline distribution, on the basis of repeat homogeneity, size, and sequence composition, and that deviations from that distribution are indicative of the nature of selection pressure at that locus. We find evidence of selective maintenance of the ability of some genes to respond very rapidly, perhaps even on intragenerational timescales, to fluctuating selective pressures.
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The orphan nuclear receptor Ear-2 is a negative coregulator for thyroid hormone nuclear receptor function. Mol Cell Biol 2000; 20:2604-18. [PMID: 10713182 PMCID: PMC85476 DOI: 10.1128/mcb.20.7.2604-2618.2000] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thyroid hormone (T3) nuclear receptors (TR) are ligand-dependent transcription factors which regulate growth, differentiation, and development. One emerging hypothesis suggests that TR mediate these diverse effects via a large network of coregulators. Recently, we found that TR-mediated transcriptional responses varied in six cell lines derived from different tissues. We therefore used human TR subtype beta1 (TRbeta1) as bait to search for coregulators in human colon carcinoma RKO cells with a yeast two-hybrid system. RKO cells exhibited T3-dependent and -independent transcriptional activation. One of the three positive clones was identified as Ear-2, which is a distant member of the chick ovalbumin upstream promoter-transcription factors of the orphan nuclear receptor family. The physical interaction between Ear-2 and TRbeta1 was further confirmed by specific binding of Ear-2 to glutathione S-transferase-TRbeta1. In addition, Ear-2 was found to associate with TRbeta1 in cells. As a result of this physical interaction, binding of TRbeta1 to the T3 response elements was inhibited. Using reporter systems, we found that both the basal activation and the T3-dependent activation mediated by TRbeta1 were repressed by Ear-2 in CV1 cells. In RKO cells, however, the T3-independent transcriptional activity was more sensitive to the repression effect of Ear-2 than the T3-dependent transcriptional activity. The repression effect of Ear-2 was reversed by steroid hormone receptor coactivator 1. These results suggest that TR-mediated responses reflect a balance of corepressors and coactivators in cells. These findings further strengthen the hypothesis that the diverse activities of TR are achieved via a large network of coregulators that includes Ear-2.
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Thyroid hormone-induced cell proliferation in GC cells is mediated by changes in G1 cyclin/cyclin-dependent kinase levels and activity. Endocrinology 1999; 140:5267-74. [PMID: 10537157 DOI: 10.1210/endo.140.11.7145] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The thyroid hormone, 3,3', 5-triiodo-L-thyronine (T3), is essential for growth and regulation of metabolic functions. The biological activities of T3 are mediated by its interaction with the thyroid hormone nuclear receptors (TRs). The mechanism by which TRs mediate cell growth is unknown. We found that T3 stimulated cell growth in GC cells by shortening the doubling time approximately 3-fold. Flow cytometric analysis indicated that the growth stimulatory effect was mainly due to shortening of G1 phase accompanied by increases in S and G2/M phases of the cell cycle. These changes correlated with T3-induced increases in messenger RNA and protein levels of two key regulators of G1 progression, cyclins D1 and E, as well as cdk2. Furthermore, the kinase activities associated with cyclin D1 and E were activated up to 4-fold by T3, which led to increased phosphorylation of the retinoblastoma protein (Rb), the driving force in G1 to S cell cycle progression. These results show for the first time that the growth promoting effect of T3 in GC cells is mediated, at least in part, by increases in cyclin/cdk activities and the phosphorylation state of Rb. The functional link of T3 to Rb has important implications for the understanding of the biology of normal and cancer cells.
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