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1.
Andrology ; 7(1): 31-41, 2019 01.
Article in English | MEDLINE | ID: mdl-30315637

ABSTRACT

BACKGROUND: Human testicular germ cell tumours (TGCT) arise from germ cell neoplasia in situ (GCNIS) cells that originate from foetal germ cell precursors. Activin A is central to normal foetal testis development, and its dysregulation may contribute to TGCT aetiology. OBJECTIVE: (i) To test whether the expression profiles of activin A targets in normal and neoplastic human testes indicates functional links with TGCT progression. (ii) To investigate whether activin A levels influence MMP activity in a neoplastic germ cell line. MATERIALS AND METHODS: (1) Bouin's fixed, paraffin-embedded human testes were utilized for PCR-based transcript analysis and immunohistochemistry. Samples (n = 5 per group) contained the following: (i) normal spermatogenesis, (ii) GCNIS or (iii) seminoma. CXCL12, CCL17, MMP2 and MMP9 were investigated. (2) The human seminoma-derived TCam-2 cell line was exposed to activin A (24 h), and target transcripts were measured by qRT-PCR (n = 4). ELISA (n = 4) and gelatin zymography (n = 3) showed changes in protein level and enzyme activity, respectively. RESULTS: (i) Cytoplasmic CXCL12 was detected in Sertoli and other somatic cells, including those surrounding seminoma cells. Anti-CCL17 labelled only the cytoplasm of Sertoli cells surrounding GCNIS, while anti-MMP2 and anti-MMP9 labelled germline and epithelial-like cells in normal and neoplastic testes. (ii) Exposing TCam-2 cells to activin A (50 ng/mL) elevated MMP2 and MMP9 transcripts (fourfold and 30-fold), while only MMP2 protein levels were significantly higher after activin A (5 ng/mL and 50 ng/mL) exposure. Importantly, gelatin zymography revealed activin A increased production of activated MMP2. DISCUSSION: Detection of CCL17 only in GCNIS tumours may reflect a change in Sertoli cell phenotype to a less mature state. Stimulation of MMP2 activity by activin A in TCam-2 cells suggests activin influences TGCT by modulating the tumour niche. CONCLUSION: This knowledge provides a basis for understanding how physiological changes that influence activin/TGF-ß superfamily signalling may alter germ cell fate.


Subject(s)
Activins/metabolism , Neoplasms, Germ Cell and Embryonal/pathology , Seminoma/pathology , Sertoli Cells/metabolism , Testicular Neoplasms/pathology , Activins/genetics , Adult , Chemokine CCL17/metabolism , Chemokine CXCL12/metabolism , Gene Expression Regulation, Neoplastic/genetics , Humans , Male , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Middle Aged , RNA, Messenger/genetics , Testis/metabolism
2.
Diabetologia ; 52(2): 218-25, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18972097

ABSTRACT

AIMS/HYPOTHESIS: Controversy surrounds whether the ratio of apolipoprotein B (ApoB) to apolipoprotein A-I (ApoA-I) is the best lipoprotein discriminator of CHD risk in non-diabetic populations, but the issue has never been investigated in type 2 diabetes. METHODS: In 2,627 participants without known vascular disease in the Collaborative Atorvastatin Diabetes Study, ApoB, ApoA-I, LDL-cholesterol (LDLC) and HDL-cholesterol (HDLC) were assayed at baseline. RESULTS: There were 108 CHD and 59 stroke endpoints over 3.9 years. The ApoB:A-I ratio at baseline was the lipoprotein variable most closely predicting CHD risk both by comparison of the hazard ratio for a 1 SD change or tertiles of frequency distribution. The areas under the receiver-operator curve for the ApoB:ApoA-I and the LDLC to HDLC [corrected] ratios, although not significantly different from each other, were greater (p = 0.0005 and p = 0.0125 respectively) than that of non-HDLC:HDLC. The 27% decrease in the ApoB:ApoA-I ratio on atorvastatin predicted a 32% (95% CI 5.4-51.2%) risk reduction in CHD, close to the 36% decrease observed. Neither the ApoB:ApoA-I nor any other lipoprotein concentration or ratio predicted the stroke outcome. CONCLUSIONS/INTERPRETATION: Overall, the ApoB:ApoA-I ratio improved on the non-HDLC:HDLC ratio in predicting CHD, but, depending on the assessment chosen, its superiority over LDLC:HDLC may be marginal. The statin-induced decrease in stroke risk may not be lipoprotein mediated. TRIAL REGISTRATION: ClinicalTrials.gov NCT00327418. FUNDING: The study was supported by unrestricted grants from Diabetes UK, the Department of Health and Pfizer to the University of Manchester and to University College, London.


Subject(s)
Apolipoproteins/blood , Cardiovascular Diseases/epidemiology , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetic Angiopathies/epidemiology , Heptanoic Acids/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Pyrroles/therapeutic use , Adult , Aged , Apolipoprotein A-I/blood , Atorvastatin , Biomarkers/blood , Blood Pressure/drug effects , Double-Blind Method , Female , Heart Rate , Humans , Male , Middle Aged , Myocardial Infarction/epidemiology , Risk Factors , Triglycerides/blood
3.
Neurology ; 70(24 Pt 2): 2364-70, 2008 Jun 10.
Article in English | MEDLINE | ID: mdl-18077795

ABSTRACT

BACKGROUND: In the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) study, atorvastatin 80 mg/day reduced the risk of stroke in patients with recent stroke or TIA. Post hoc analysis found this overall benefit included an increase in the numbers of treated patients having hemorrhagic stroke (n = 55 for active treatment vs n = 33 for placebo). METHODS: We explored the relationships between hemorrhage risk and treatment, baseline patient characteristics, most recent blood pressure, and most recent low-density lipoprotein (LDL) cholesterol levels prior to the hemorrhage. RESULTS: Of 4,731 patients, 67% had ischemic strokes, 31% TIAs, and 2% hemorrhagic strokes as entry events. In addition to atorvastatin treatment (HR 1.68, 95% CI 1.09 to 2.59, p = 0.02), Cox multivariable regression including baseline variables significant in univariable analyses showed that hemorrhagic stroke risk was higher in those having a hemorrhagic stroke as the entry event (HR 5.65, 95% CI 2.82 to 11.30, p < 0.001), in men (HR 1.79, 95% CI 1.13 to 2.84, p = 0.01), and with age (10 y increments, HR 1.42, 95% CI 1.16 to 1.74, p = 0.001). There were no statistical interactions between these factors and treatment. Multivariable analyses also found that having Stage 2 (JNC-7) hypertension at the last study visit before a hemorrhagic stroke increased risk (HR 6.19, 95% CI 1.47 to 26.11, p = 0.01), but there was no effect of most recent LDL-cholesterol level in those treated with atorvastatin. CONCLUSIONS: Hemorrhagic stroke was more frequent in those treated with atorvastatin, in those with a hemorrhagic stroke as an entry event, in men, and increased with age. Those with Stage 2 hypertension at the last visit prior to the hemorrhagic stroke were also at increased risk. Treatment did not disproportionately affect the hemorrhagic stroke risk associated with these other factors. There were no relationships between hemorrhage risk and baseline low-density lipoprotein (LDL) cholesterol level or recent LDL cholesterol level in treated patients.


Subject(s)
Anticholesteremic Agents/therapeutic use , Cerebral Infarction/prevention & control , Heptanoic Acids/therapeutic use , Pyrroles/therapeutic use , Adult , Atorvastatin , Cerebral Infarction/blood , Cerebral Infarction/epidemiology , Cholesterol, LDL/blood , Comorbidity , Double-Blind Method , Female , Humans , Hypertension/epidemiology , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Risk Assessment , Secondary Prevention , Sex Factors
4.
Diabet Med ; 24(12): 1313-21, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17894827

ABSTRACT

AIMS: Patients with Type 2 diabetes have an elevated risk of stroke. The role of lipid levels and diabetes-specific factors in risk prediction of stroke is unclear, and estimates of efficacy of lipid-lowering therapy vary between trials. We examined predictors of stroke and the effect of atorvastatin on specific stroke subtypes in Type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS) [a trial of 2838 participants with mean low-density lipoprotein cholesterol < 4.14 mmol/l, no history of macrovascular disease and randomized to atorvastatin 10 mg daily or placebo]. METHODS: Median follow-up was 3.9 years. Cox regression models were used to estimate the effect of atorvastatin on stroke rate and risk of stroke associated with baseline risk factors. Risk factors that predicted stroke in univariate models were examined in a multivariable model. RESULTS: Independent risk factors predicting stroke were age [10-year increments; hazard ratio (HR) 2.3, P < 0.001], microalbuminuria (albumin : creatinine ratio > 2.5 mg/mmol; HR 2.0, P = 0.007) and glycaemic control (HbA(1c) > 10%; HR 2.7, P = 0.007). Women were at lower risk of stroke (HR 0.3, P = 0.004). Lipids did not predict stroke. Of 60 first strokes, 47 were non-haemorrhagic, 13 were indeterminate and none was definitely haemorrhagic. Atorvastatin treatment was associated with 50% reduction in non-haemorrhagic stroke (95% confidence interval 9%-72%P = 0.024), similar to the 48% reduction (11%-69%) for all strokes combined. CONCLUSIONS: Diabetes-specific risk factors are important predictors of stroke in Type 2 diabetes. Despite the lack of association between baseline lipids and first stroke, there was a reduction of 50% of non-haemorrhagic strokes associated with atorvastatin treatment in the CARDS population.


Subject(s)
Anticholesteremic Agents/therapeutic use , Diabetes Mellitus, Type 2/complications , Diabetic Angiopathies/prevention & control , Heptanoic Acids/therapeutic use , Pyrroles/therapeutic use , Stroke/prevention & control , Adult , Aged , Atorvastatin , Blood Pressure , Diabetes Mellitus, Type 2/blood , Double-Blind Method , Female , Glycated Hemoglobin/analysis , Humans , Lipoproteins/blood , Male , Middle Aged , Risk Factors , Stroke/etiology
5.
Carbohydr Res ; 325(1): 30-45, 2000 Mar 24.
Article in English | MEDLINE | ID: mdl-10741825

ABSTRACT

4-Deoxy analogues of 2-acetamido-2-deoxy-D-glucose and 2-acetamido-2-deoxy-D-xylose were synthesized and evaluated as inhibitors of glycoconjugate biosynthesis. Methyl 2-acetamido-2,4-dideoxy-beta-D-xylo-hexopyranoside (11) showed a reduction in [3H]GlcN and [14C]Leu incorporation into hepatocyte cellular glycoconjugates by 89 and 88%, of the control cells, respectively, at 20 mM, whereas the free sugars, 2-acetamido-2,4-dideoxy-alpha,beta-D-xylo-hexopyranoses (15), showed a reduction of [3H]GlcN and [14C]Leu incorporation by 75 and 64%, respectively, at 20 mM. The acetylated analogues of 11 and 15, namely methyl 2-acetamido-3,6-di-O-acetyl-2,4-dideoxy-beta-D-xylo-hexopyranoside and 2-acetamido-1,3,6-tri-O-acetyl-2,4-dideoxy-alpha,beta-D-xylo-hexopyra noses, showed a greater inhibition of [3H]GlcN and [14C]Leu incorporation at 1 mM compared with their non-acetylated counterparts, but were toxic to hepatocytes at concentrations of 10 and 20 mM. Corresponding derivatives of 2-acetamido-2,4-dideoxy-L-threo-pentopyranose showed no biological effect up to 20 mM, suggesting that the C-6 substituent is important for the biological activity.


Subject(s)
Deoxy Sugars/chemical synthesis , Glycoconjugates/biosynthesis , Acetylglucosamine/analogs & derivatives , Animals , Carbohydrate Conformation , Cells, Cultured , Deoxy Sugars/pharmacology , Leucine/metabolism , Liver/drug effects , Liver/metabolism , Magnetic Resonance Spectroscopy , Mice , Xylose/analogs & derivatives
6.
Int J Neurosci ; 97(1-2): 41-59, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10681117

ABSTRACT

Previous studies indicate that low level chemical intolerance (CI) is a symptom of several different controversial conditions with neuropsychiatric features, e.g., chronic fatigue syndrome, fibromyalgia, multiple chemical sensitivity, and "Persian Gulf Syndrome". Prior studies suggest that limbic and/or mesolimbic sensitization may contribute to development of CI. The purpose of this report was to document the waking electroencephalographic (EEG) patterns of individuals with CI during chemical exposures presented over repeated sessions. Three groups of adult subjects who were recruited from the community participated in the study: self-reported CI who had made associated lifestyle changes due to their intolerance (CI/ LSC), self-reported CI who had not made such changes (CI), and normal controls without self-reported CI. Subjects underwent two sessions involving one-minute EEG recordings during exposures to low level chemical odors (a probe for limbic activation). The CI, but not the CI/ LSC, subjects had increased absolute delta power after the chemical exposures during the second, but not the first, session. The findings support the neural sensitization hypothesis for intolerance to low levels of environmental chemicals in vulnerable individuals. As in human studies of stimulant drug sensitization, those with the strongest past history with sensitizing agents may not show-term sensitization to low level exposures in the laboratory.


Subject(s)
Electroencephalography/drug effects , Multiple Chemical Sensitivity/physiopathology , Adult , Benzopyrans/pharmacology , Female , Humans , Life Style , Male , Middle Aged , Multiple Chemical Sensitivity/psychology , Odorants , Perfume , Psychiatric Status Rating Scales , Surveys and Questionnaires
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