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Ergene A, Tan S, Mirici S, Güler P, Yıldırım S. ANTIMICROBIAL ACTIVITY OF HERACLEUM ANTASIATICUM. ACTA ACUST UNITED AC 2009. [DOI: 10.17660/actahortic.2009.826.36] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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277
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Lee J, Chong C, Seah J, Tan S. 0221 Locally advanced breast cancer in Asian women. Breast 2009. [DOI: 10.1016/s0960-9776(09)70238-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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278
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Benson S, Hahn S, Tan S, Mann K, Janssen OE, Schedlowski M, Elsenbruch S. Prevalence and implications of anxiety in polycystic ovary syndrome: results of an internet-based survey in Germany. Hum Reprod 2009; 24:1446-51. [PMID: 19223290 DOI: 10.1093/humrep/dep031] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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279
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Benson S, Arck PC, Tan S, Mann K, Hahn S, Janssen OE, Schedlowski M, Elsenbruch S. Effects of obesity on neuroendocrine, cardiovascular, and immune cell responses to acute psychosocial stress in premenopausal women. Psychoneuroendocrinology 2009; 34:181-189. [PMID: 18838227 DOI: 10.1016/j.psyneuen.2008.08.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 08/05/2008] [Accepted: 08/26/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To analyze the neuroendocrine and immune cell responses to acute psychosocial stress in obese compared to non-obese premenopausal women. METHODS N=15 obese (BMI> or =30) and N=24 (BMI<30) non-obese premenopausal women underwent public speaking stress. State anxiety, ACTH, cortisol, and the redistribution of immune cells were measured before, during, and 10 and 45min after public speaking. Serum hsCRP and serum IL-6 levels were analyzed before, and IL-6 additionally 45min after stress. RESULTS In response to public speaking stress, both groups showed significant but comparable increases in state anxiety, plasma ACTH, and blood pressure (all p<0.01; time effects). The cortisol stress response was significantly enhanced in obese women (p<0.05; interaction effect). In addition, heart rate and diastolic blood pressure were significantly higher in obese women 10min following stress (p<0.05, t-tests). Public speaking stress led to a significant increase in IL-6 concentrations (p<0.001; time effect), and obese women displayed higher IL-6 levels both pre- and post-stress (p<0.05; group effect; between-group t-tests: pre-stress p<0.05; post-stress p<0.01). Baseline numbers of circulating leukocytes, granulocytes, CD3+ cells and hsCRP concentration were significantly higher in obese women (between-group t-tests: all p<0.05, but the groups did not differ in the stress-induced redistribution of circulating leukocyte subpopulations. CONCLUSIONS Our data reveal a strong association of obesity with chronic low-grade inflammation in premenopausal women. This pro-inflammatory state, together with altered neuroendocrine and cardiovascular stress responsiveness, may conceivably constitute one of the mechanisms linking psychological stress and the long-term health risks associated with obesity.
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280
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Lim PG, Tan S, Ahmad TS. The role of wrist anthropometric measurement in idiopathic carpal tunnel syndrome. J Hand Surg Eur Vol 2008; 33:645-7. [PMID: 18662961 DOI: 10.1177/1753193408093326] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Anthropometric wrist measurement ratios were examined for an association with idiopathic carpal tunnel syndrome (CTS). Wrist measurements were recorded in 67 patients with CTS and in a matched control group of 67 healthy volunteers. The Wrist Ratio (WR) (wrist anterior to posterior dimension/wrist medial-lateral dimension) and the Wrist Palm Ratio (wrist anterior to posterior dimension/palm length) were calculated for each case. We found that a WR of > or =0.70 and a Wrist Palm Ratio of >0.342 were significantly associated with idiopathic CTS.
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Culp P, Choi D, Yin J, Tan S, Chao D, Su M, Sho M, Steinle R, Hsi E, Ramakrishnan V. 508 POSTER PDL192, a novel, humanized antibody to TWEAK receptor, shows potent anti-tumor activity in preclinical models. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72442-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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282
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Hu W, Tang L, Wang J, Wang B, Li S, Yu H, Tang W, Li H, Tan S, Shou W, Xiao C. Polymorphism of HLA-DRB1, -DQB1 and -DPB1 genes in Bai ethnic group in southwestern China. ACTA ACUST UNITED AC 2008; 72:474-7. [PMID: 18778327 DOI: 10.1111/j.1399-0039.2008.01120.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, polymorphism of human leukocyte antigen (HLA)-DRB1, -DQB1 and -DPB1 genes was detected using polymerase chain reaction-sequence-based typing method in 128 healthy unrelated volunteers from the Bai ethnic group of Yunnan province of southwest China. Among all the 28 alleles detected for the DRB1 gene, the most common allele was DRB1*120201 with a frequency of 16.41%, followed by DRB1*090102, DRB1*080302, DRB1*1404, DRB1*150101, DRB1*140101 and DRB1*160201, with frequencies of 10.16%, 9.77%, 9.38%, 8.98%, 8.59% and 8.21%, respectively. Among 19 DQB1 alleles detected, the most frequent allele was DQB1*030101/0309 (35.94%), followed by DQB1*050201 (11.33%), DQB1*060101/060103 (10.54%) and DQB1*0401 (10.16%). For the DPB1 locus, the most common alleles were DPB1*0501 (42.19%), DPB1*1301 (13.28%), DPB1*020102 (10.93%) and DPB1*040101 (9.77%). The comparison of HLA class II allele frequencies of Bais with those of other Chinese populations suggested that the Bai ethnic group belonged to the southern group of Chinese.
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von Conrady D, Smith MJ, Khan MF, Tan S, Mortimer G, McAnena OJ. Progression of Barrett's esophagus to adenocarcinoma despite antireflux surgery. Endoscopy 2008; 40 Suppl 2:E68-9. [PMID: 18633915 DOI: 10.1055/s-2007-995507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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284
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Shenq Chen, Lajos Hanzo, Tan S. Symmetric Complex-Valued RBF Receiver for Multiple-Antenna-Aided Wireless Systems. ACTA ACUST UNITED AC 2008; 19:1659-65. [DOI: 10.1109/tnn.2008.2000582] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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285
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Dahan M, Agdi M, Shehata F, Dean N, Tan S. A comparison of in-vitro fertilization cycles using recombinant and menopausal luteinizing hormone (LH). Fertil Steril 2008. [DOI: 10.1016/j.fertnstert.2008.07.1428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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286
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Dye BA, Nowjack-Raymer R, Barker LK, Nunn JH, Steele JG, Tan S, Lewis BG, Beltran-Aguilar ED. Overview and Quality Assurance for the Oral Health Component of the National Health and Nutrition Examination Survey (NHANES), 2003-04. J Public Health Dent 2008; 68:218-26. [DOI: 10.1111/j.1752-7325.2007.00076.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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287
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Tan S, Hahn S, Benson S, Janssen O, Dietz T, Kimmig R, Hesse-Hussain J, Mann K, Schedlowski M, Arck P, Elsenbruch S. Psychological implications of infertility in women with polycystic ovary syndrome. Hum Reprod 2008; 23:2064-71. [DOI: 10.1093/humrep/den227] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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288
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Maiya S, Tan S, Grimer RJ. Recurrent episodic foot-drop following surgery to the thigh. Sarcoma 2008; 4:183-4. [PMID: 18521300 PMCID: PMC2395447 DOI: 10.1080/13577140020025913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Subject. We present the case history of a 47-year-old lady who,
10 months following excision of a soft tissue sarcoma from the left thigh, was struck with
recurrent episodes of foot drop. Discussion. The curious phenomenon of recurrent foot drop was found
to be secondary to pressure symptoms from a tense seroma of the thigh. She underwent
surgical excision of the sac and had immediate and complete relief of symptoms.
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Ruigrok YM, Tan S, Medic J, Rinkel GJE, Wijmenga C. Genes involved in the transforming growth factor beta signalling pathway and the risk of intracranial aneurysms. J Neurol Neurosurg Psychiatry 2008; 79:722-4. [PMID: 18487557 DOI: 10.1136/jnnp.2007.128041] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND PURPOSE The 19q13.3 locus for intracranial aneurysms (IA) partly overlaps with the 19q13 locus for abdominal aortic aneurysms (AAA). A common genetic risk factor located in this locus for the two aneurysm types seems plausible. The transforming growth factor beta (TGF-beta) signalling pathway plays a role in aortic aneurysms but may also play a role in aneurysms in general. In the combined region of the 19q13 loci for IA and AAA we identified two candidate genes that are both involved in the TGF-beta signalling pathway: hepsin (HPN) and the latent transforming growth factor beta-binding protein 4 (LTBP4). We hypothesised that single nucleotide polymorphisms (SNP) in the HPN and LTBP4 genes are associated with IA. METHODS We analyzed all the common variations using tag SNP in the HPN and LTBP4 genes for association with IA in 390 patients and 642 controls in the Dutch population. Six tag SNP in the HPN gene and five tag SNP in the LTBP4 gene were genotyped. RESULTS No differences in SNP frequency were observed for both the HPN and LTBP4 gene between patients and controls. CONCLUSION Our findings suggest that variations in or near the HPN and LTBP4 genes do not play a role in the susceptibility to IA in the Dutch population.
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Yeo W, Soong RC, Chuah BY, Tan S, Lim S, Cordero MT, Wang L, Ng S, Goh BC, Lee S. Correlation of RRM1 promoter region single nucleotide polymorphisms (SNPs) with response and outcome in breast cancer patients treated with gemcitabine-based chemotherapy. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.14513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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291
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Tan S, Jiao L, Kakadiaris IA. Wavelet-based Bayesian image estimation: from marginal and bivariate prior models to multivariate prior models. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2008; 17:469-481. [PMID: 18390356 DOI: 10.1109/tip.2008.918018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Prior models play an important role in the wavelet-based Bayesian image estimation problem. Although it is well known that a residual dependency structure always remains among natural image wavelet coefficients, only few multivariate prior models with a closed parametric form are available in the literature. In this paper, we develop new multivariate prior models that not only match well with the observed statistics of the wavelet coefficients of natural images, but also have a simple parametric form. These prior models are very effective for Bayesian image estimation and lead to an improved estimation performance over related earlier techniques.
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Benson S, Janssen OE, Hahn S, Tan S, Dietz T, Mann K, Pleger K, Schedlowski M, Arck PC, Elsenbruch S. Obesity, depression, and chronic low-grade inflammation in women with polycystic ovary syndrome. Brain Behav Immun 2008; 22:177-84. [PMID: 17716857 DOI: 10.1016/j.bbi.2007.07.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 06/28/2007] [Accepted: 07/13/2007] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Women with polycystic ovary syndrome (PCOS) present with multiple risk factors for cardiovascular diseases at a young age, including obesity and chronic low-grade inflammation. Since depression is common in PCOS, this study aimed to address whether depression correlates with indices of chronic low-grade inflammation beyond the association with obesity. METHODS Serum concentrations of IL-6, the stimulated production of IFN-gamma, TNF-alpha, IL-2, IL-4, IL-5, and IL-10, leukocyte numbers, and hsCRP were analyzed in 57 PCOS patients and 28 healthy women, together with clinical parameters, including body mass index (BMI), testosterone, and insulin resistance (HOMA-IR), and psychological parameters, including Beck Depression Inventory (BDI) and health-related quality-of-life (SF-36) scores. RESULTS PCOS patients demonstrated significantly increased hsCRP, IL-6, and leukocyte numbers. Group differences in IL-6 and leukocyte numbers, but not hsCRP, disappeared after controlling for BMI. The stimulated production of IFN-gamma, TNF-alpha, IL-2, IL-4, and IL-5 was significantly decreased, irrespective of BMI. In PCOS, hsCRP, IL-6, and leukocyte numbers were correlated with BMI, HDL, diastolic blood pressure, and with insulin resistance. On the other hand, no correlations were found with depression scores or with PCOS-specific endocrine abnormalities. In regression models, BMI was a significant predictor of the key immune markers, and explained a large amount of variance, whereas BDI was not included in either model. CONCLUSIONS These data confirm that obesity plays a pivotal role in inflammatory processes relevant to cardiovascular risk in women with PCOS. However, even lean PCOS patients may display subtle alterations in specific aspects of immunity. Our findings did not support a correlation of depression with chronic low-grade inflammation in PCOS.
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Wang B, Hu W, Wang J, Li S, Yu H, Tang W, Tan S, Shou W, Zhang J, Xiao C. HLA-DPB1 polymorphism in Blang and Puyi ethnic groups of southwest China inferred from sequence-based typing. ACTA ACUST UNITED AC 2007; 71:81-4. [PMID: 17971047 DOI: 10.1111/j.1399-0039.2007.00963.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present study, DNA typing for HLA-DPB1 was performed using polymerase chain reaction (PCR)-sequence-based typing method in two isolated Chinese populations: the Blangs (n = 94) in Shuangjiang County and the Puyis (n = 76) in Luoping County from Yunnan province of Southwest China. These two populations exhibited certain similarity in their allelic distributions of the HLA-DPB1 gene. A total of 11 and 12 alleles at the DPB1 locus were found in the Blang and Puyi groups, respectively. In the Blang group, the most frequent alleles were DPB1*0501 (51.0%) and DPB1*1301 (17.0%). DPB1*030101 was also common with a frequency of 6.4%. In the Puyi group, the most frequent allele was also DPB1*0501 with a frequency of 47.5%, followed by DPB1*1301 (21.1%). Two alleles DPB1*2101 and DPB1*0202 followed, with frequencies ranging between 5% and 8%. The alleles DPB1*4101, DPB1*3301, DPB1*6801 and DPB1*8401 were found for the first time in Chinese populations. A dendrogram constructed by neighbor-joining method showed that the Blang and Puyi ethnic minorities, which had the closest relationship belonged to the southern Chinese.
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Ghazali N, Bentley R, Tan S, Hameed S, Ebert J, Coward T, Huppa C. Outcomes of cranioplasty using computer-aided designed titanium plates. Br J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.bjoms.2007.07.079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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295
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Zeng X, Tan S, Neo B, Sasajala P, Low D, Udolph G. Integration and tissue specific differentiation of fetal cells into maternal organs in a murine pregnancy model suggests multilineage differentiation potential. J Stem Cells Regen Med 2007; 2:24-25. [PMID: 24692885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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296
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Tan S, Hahn S, Benson S, Elsenbruch S, Jansen T, Grabbe S, Mann K, Janssen OE. Influence of metformin on acne papulopustulosa in women with polycystic ovary syndrome. Exp Clin Endocrinol Diabetes 2007. [DOI: 10.1055/s-2007-972415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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297
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Tan S, Hahn S, Sack S, Benson S, Elsenbruch S, Schmidt M, Kimmig R, Erbel R, Mann K, Janssen OE. The polycystic ovary syndrome phenotype modulates prevalence of the metabolic syndrome. Exp Clin Endocrinol Diabetes 2007. [DOI: 10.1055/s-2007-972269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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298
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Hahn S, Tan S, Sack S, Kimmig R, Quadbeck B, Mann K, Janssen OE. Prevalence of the metabolic syndrome in German women with polycystic ovary syndrome. Exp Clin Endocrinol Diabetes 2007; 115:130-5. [PMID: 17318774 DOI: 10.1055/s-2007-967093] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The aim of our study was to evaluate the prevalence of the metabolic syndrome (MBS) according to the current International Diabetes Federation definition in German PCOS women. Four hundred and eleven PCOS patients (age 28+/-6.3 years) and 82 controls (age 28+/-7.5 years) were evaluated for anthropometric and metabolic parameters by physical examination, blood testing and a personal interview including family history. A subgroup analysis of controls with BMI-matched PCOS women (BMI 22.9+/-2.8 kg/m (2)) was performed to detect PCOS specific differences in metabolic variables between the groups. The MBS was found in 33.8% of PCOS women compared to 7.3% in the control group. Parameters of insulin resistance, lipid-and glucose metabolism, mean values of all criteria of the MBS as well as the prevalence of the MBS were significantly different between the entire PCOS cohort and controls, but did not differ between BMI-matched PCOS women and controls. In addition, the prevalence of the MBS increased with age. Moreover, in PCOS women an increase in BMI and insulin resistance was accompanied by a further significant increase in the severity of clinical and biochemical hyperandrogenism. In PCOS women, while one out of three PCOS women had the MBS, the presence of metabolic abnormalities did not appear to be associated with PCOS per se, but rather correlated with age and the degree of obesity.
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O'Brien MER, Borthwick A, Rigg A, Leary A, Assersohn L, Last K, Tan S, Milan S, Tait D, Smith IE. Mortality within 30 days of chemotherapy: a clinical governance benchmarking issue for oncology patients. Br J Cancer 2007; 95:1632-6. [PMID: 17160081 PMCID: PMC2360753 DOI: 10.1038/sj.bjc.6603498] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
No national benchmark figures exist for early mortality due to chemotherapy unlike for surgical interventions. Deaths within 30 days of chemotherapy during a 6-month period were identified from the Royal Marsden Hospital electronic patient records. Treatment intention – curative or palliative, cause of death and number of previous treatments – were documented. Between April 2005 and September 2005, 1976 patients received chemotherapy with 161 deaths within 30 days of chemotherapy (8.1%). Of these, 124 deaths (77.0%) were due to disease progression. Of the other 37 deaths, 12 (7.5%) were related to chemotherapy, six each for solid tumours and haematological malignancies, of which seven (4.3%) were due to neutropenic sepsis. For the remaining 25 deaths (15.5%) there was insufficient information. There were more deaths after third and subsequent lines of therapy than with first and secondlines of therapy. Only 12 of the 161 deaths occurred in patients who were receiving potentially curative chemotherapy to give a mortality rate in breast and gastrointestinal malignancy of 0.5 and 1.5%, respectively. It is possible to audit mortality within 30 days of chemotherapy and this should become a benchmark for standard practice nationally. Most deaths were due to disease progression in the palliative setting. We practice this form of audit each quarter and feed back to the treating teams so that deaths are discussed and practice monitored.
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Al-Asmakh M, Race H, Tan S, Sullivan MHF. The effects of oxygen concentration on in vitro output of prostaglandin E2 and interleukin-6 from human fetal membranes. Mol Hum Reprod 2007; 13:197-201. [PMID: 17208929 DOI: 10.1093/molehr/gal109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Labour at all gestational ages has clear biochemical parallels with an inflammatory response, typified by the increased output of prostaglandins (PGs) and cytokines within the pregnant uterus. The main sources are the fetal membranes, including the amnion, chorion and decidua, and it is well established that stimuli [bacteria, bacterial endotoxins, interleukin (IL)-1beta, corticotrophin releasing hormone and platelet activating factor], as well as negative regulators (progesterone and IL-10), control the net output of PGs and cytokines in vitro. In this study, we have investigated the effect of oxygen tension on fetal membrane biology, as a reconsideration of the literature suggests that fetal membranes are normally exposed to approximately 3% O(2) (approximately 20 mmHg) in vivo, rather than the 20% O(2) (150 mmHg) used for in vitro culture. The output of prostaglandin E(2) from non-activated fetal membranes in response to IL-1beta was decreased by approximately 80% at 16 and 24 h of culture, whereas the inhibition of IL-6 production was time-dependent, reaching 90% after 16 h and 50% after 24 h. Tissues obtained after labour (or after the activation of inflammatory processes leading to labour) were not inhibited by the low levels of oxygen, indicating that only before the onset of labour does oxygen regulate fetal membrane biology. The data identify oxygen as a regulator of fetal membrane inflammatory functions during human pregnancy, and its mechanism of action requires further study.
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