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Byams VR, Kouides PA, Kulkarni R, Baker JR, Brown DL, Gill JC, Grant AM, James AH, Konkle BA, Maahs J, Dumas MM, McAlister S, Nance D, Nugent D, Philipp CS, Soucie JM, Stang E. Surveillance of female patients with inherited bleeding disorders in United States Haemophilia Treatment Centres. Haemophilia 2011; 17 Suppl 1:6-13. [PMID: 21692922 PMCID: PMC4467796 DOI: 10.1111/j.1365-2516.2011.02558.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Inherited bleeding disorders are especially problematic for affected girls and women due to the monthly occurrence of menstrual periods and the effects on reproductive health. Although heavy menstrual bleeding (HMB) is the most common manifestation, females with inherited bleeding disorders (FBD) experience other bleeding symptoms throughout the lifespan that can lead to increased morbidity and impairment of daily activities. The purpose of this article is to describe the utility of a female-focused surveillance effort [female Universal Data Collection (UDC) project] in the United States Haemophilia Treatment Centres (HTCs) and to describe the baseline frequency and spectrum of diagnoses and outcomes. All FBD aged 2 years and older receiving care at selected HTCs were eligible for enrollment. Demographic data, diagnoses and historical data regarding bleeding symptoms, treatments, gynaecological abnormalities and obstetrical outcomes were analysed. Analyses represent data collected from 2009 to 2010. The most frequent diagnoses were type 1 von Willebrand's disease (VWD) (195/319; 61.1%), VWD type unknown (49/319; 15.4%) and factor VIII deficiency (40/319; 12.5%). HMB was the most common bleeding symptom (198/253; 78.3%); however, 157 (49.2%) participants reported greater than four symptoms. Oral contraceptives were used most frequently to treat HMB (90/165; 54.5%), followed by desmopressin [1-8 deamino-D-arginine vasopressin (DDAVP)] (56/165; 33.9%). Various pregnancy and childbirth complications were reported, including bleeding during miscarriage (33/43; 76.7%) and postpartum haemorrhage (PPH) (41/109; 37.6%). FBD experience multiple bleeding symptoms and obstetrical-gynaecological morbidity. The female UDC is the first prospective, longitudinal surveillance in the US focusing on FBD and has the potential to further identify complications and reduce adverse outcomes in this population.
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Kim JK, Shukla R, Casagrande L, Sedgley C, Nör JE, Baker JR, Hill EE. Differentiating dental pulp cells via RGD-dendrimer conjugates. J Dent Res 2010; 89:1433-8. [PMID: 20929719 DOI: 10.1177/0022034510384870] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Traumatic dental injuries are often irreversible, underscoring the need for therapies that protect dental pulp cells and enhance their regeneration. We hypothesized that generation 5 poly amido amine (PAMAM) dendrimers (G5), functionalized with fluorescein isothiocyanate (FL) and αVβ3-specific, cyclic arginine-glycine-aspartic acid (RGD) peptides, will bind to dental pulp cells (DPCs) and modulate their differentiation. Dental pulp cells and mouse odontoblast-like cells (MDPC-23) (±) treated with G5-FL-RGD were analyzed via Western blot, RT-PCR, and quantitative PCR. Transcription of dental differentiation markers was as follows: Dentin matrix protein (DMP-1), dentin sialoprotein (DSPP), and matrix extracellular phosphoglycoprotein (MEPE) as well as vascular endothelial growth factor (VEGF) all increased via the JNK pathway. Long-term G5-RGD treatment of dental pulp cells resulted in enhanced mineralization as examined via Von Kossa assay, suggesting that PAMAM dendrimers conjugated to cyclic RGD peptides can increase the odontogenic potential of these cells.
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Cooper GJS, Young AA, Gamble GD, Occleshaw CJ, Dissanayake AM, Cowan BR, Brunton DH, Baker JR, Phillips ARJ, Frampton CM, Poppitt SD, Doughty RN. A copper(II)-selective chelator ameliorates left-ventricular hypertrophy in type 2 diabetic patients: a randomised placebo-controlled study. Diabetologia 2009; 52:715-22. [PMID: 19172243 DOI: 10.1007/s00125-009-1265-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Accepted: 12/11/2008] [Indexed: 01/19/2023]
Abstract
AIMS/HYPOTHESIS Cu(II)-selective chelation with trientine ameliorates cardiovascular and renal disease in a model of diabetes in rats. Here, we tested the hypothesis that Cu(II)-selective chelation might improve left ventricular hypertrophy (LVH) in type 2 diabetic patients. METHODS We performed a 12 month randomised placebo-controlled study of the effects of treatment with the Cu(II)-selective chelator trientine (triethylenetetramine dihydrochloride, 600 mg given orally twice daily) on LVH in diabetic patients (n = 15/group at baseline) in an outpatient setting wherein participants, caregivers and those assessing outcomes were blinded to group assignment. Using MRI, we measured left ventricular variables at baseline, and at months 6 and 12. The change from baseline in left ventricular mass indexed to body surface area (LVM(bsa)) was the primary endpoint variable. RESULTS Diabetic patients had LVH with preserved ejection fraction at baseline. Trientine treatment decreased LVM(bsa) by 5.0 +/- 7.2 g/m(2) (mean +/- SD) at month 6 (when 14 trientine-treated and 14 placebo-treated participants were analysed; p = 0.0056 compared with placebo) and by 10.6 +/- 7.6 g/m(2) at month 12 (when nine trientine-treated and 13 placebo-treated participants were analysed; p = 0.0088), whereas LVM(bsa) was unchanged by placebo treatment. In a multiple-regression model that explained ~75% of variation (R (2) = 0.748, p = 0.001), cumulative urinary Cu excretion over 12 months was positively associated with trientine-evoked decreases in LVM(bsa). CONCLUSIONS/INTERPRETATION Cu(II)-selective chelation merits further exploration as a potential pharmacotherapy for diabetic heart disease. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry ACTRN 12609000053224 FUNDING: The Endocore Research Trust; Lottery Health New Zealand; the Maurice and Phyllis Paykel Trust; the Foundation of Research, Science and Technology (New Zealand); the Health Research Council of New Zealand; the Ministry of Education (New Zealand) through the Maurice Wilkins Centre for Molecular Biodiscovery; and the Protemix Corporation.
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Baker JR, Thominet O, Britton H, Caddick S. An Efficient Synthesis of Epoxydiynes and a Key Fragment of Neocarzinostatin Chromophore. Org Lett 2006; 9:45-8. [PMID: 17192081 DOI: 10.1021/ol062461g] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] A key structural feature of the Neocarzinostatin chromophore is a reactive epoxydiyne. We present here a new method for the preparation of epoxydiynes by the addition of an allenyl zinc bromide to a propargylic ketone.
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Baker JR, Edwards RJ, Lasker JM, Moore MR, Satarug S. Renal and hepatic accumulation of cadmium and lead in the expression of CYP4F2 and CYP2E1. Toxicol Lett 2005; 159:182-91. [PMID: 15994032 DOI: 10.1016/j.toxlet.2005.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Revised: 05/20/2005] [Accepted: 05/20/2005] [Indexed: 12/31/2022]
Abstract
The present study examined accumulation of the metal toxins cadmium (Cd) and lead (Pb) in relation to the abundance of cytochrome P450 4F2 (CYP4F2), CYP2E1 and concentrations of zinc and copper in liver and kidney samples using immunoblotting coupled with metal analysis. The post mortem liver and kidney cortex samples were from 23 males and 8 females aged 3-89 years. All were Caucasians who had not been exposed to metals in the workplace. Average kidney cortex Cd load of 17.4 microg/g w.w. was 17 times greater than average liver Cd load (1.1 microg/g w.w.). In contrast, average kidney cortex Pb load of 0.09 microg/g w.w. was two times lower than liver Pb load of 0.19 microg/g w.w. Average Zn and Cu concentrations in the kidney cortex samples were 67% and 33% lower than those in the liver. Liver and kidney Cd loads, but not liver or kidney Pb loads, correlated positively with donors' age. After controlling for liver Cd load, an inverse correlation was seen between Zn and age (partial r=-0.39, P=0.02), suggesting reduction in liver Zn levels in old age. Liver CYP2E1 protein abundance correlated with age-adjusted Cd load (partial r=0.37, P=0.02) whereas kidney CYP4F2 protein abundance showed a positive correlation with age-adjusted Cd loads (partial r=0.40, P=0.02). These findings suggest that Cd may be an inducer of renal CYP4F2 and hepatic CYP2E1 and that increased renal CYP4F2 expression may implicate in Cd-linked renal tubular dysfunction and high blood pressure, involving CYP4F2-dependent arachidonic acid metabolism.
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Baker JR. Stress management. Stress, like pain, is inevitable--suffering is optional. THE JOURNAL OF THE ARKANSAS MEDICAL SOCIETY 2005; 101:227. [PMID: 15648204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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Satarug S, Ujjin P, Vanavanitkun Y, Nishijo M, Baker JR, Moore MR. Effects of cigarette smoking and exposure to cadmium and lead on phenotypic variability of hepatic CYP2A6 and renal function biomarkers in men. Toxicology 2004; 204:161-73. [PMID: 15388242 DOI: 10.1016/j.tox.2004.06.022] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Revised: 06/19/2004] [Accepted: 06/21/2004] [Indexed: 11/26/2022]
Abstract
Effects of cigarette smoking and exposure to dietary cadmium (Cd) and lead (Pb) on urinary biomarkers of renal function and phenotypic variability of cytochrome P450 2A6 (CYP2A6) were investigated in a group of 96 healthy Thai men with mean age of 36.7 year (19-57 years). In non-smokers, Cd burden increased with age (r = 0.47, P < 0.001). In current smokers, Cd burden increased with both age (r = 0.45, P = 0.01) and number of cigarettes smoked per day (r = 0.32, P = 0.05). Cd-linked renal tubular dysfunction was seen in both smokers and non-smokers, but Pb-linked glomerular dysfunction was seen in smokers only, possibly due to more recent exposure to high levels of Cd and Pb, as reflected by 30-50% higher serum Cd and Pb levels in smokers than non-smokers (P < 0.05). Exposure to dietary Cd and Pb appeared to be associated with mild tubular dysfunction whereas dietary exposure plus cigarette smoking was associated with tubular plus glomerular dysfunction. Hepatic CYP2A6 activity in non-smokers showed a positive association with Cd burden (adjusted beta = 0.38, P = 0.006), but it showed an inverse correlation with Pb (adjusted beta = -0.29, P = 0.003), suggesting opposing effects of Cd and Pb on hepatic CYP2A6 phenotype. In contrast, CYP2A6 activity in current smokers did not correlate with Cd or Pb, but it showed a positive correlation with serum ferritin levels (r = 0.45, P = 0.01). These finding suggest that Pb concentrations in the liver probably were too low to inhibit hepatic synthesis of heme and CYP2A6 and that the concurrent induction of hepatic CYP2A6 and ferritin was probably due to cigarette smoke constituents other than Cd and Pb.
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Satarug S, Nishijo M, Ujjin P, Vanavanitkun Y, Baker JR, Moore MR. Evidence for concurrent effects of exposure to environmental cadmium and lead on hepatic CYP2A6 phenotype and renal function biomarkers in nonsmokers. ENVIRONMENTAL HEALTH PERSPECTIVES 2004; 112:1512-8. [PMID: 15531436 PMCID: PMC1247615 DOI: 10.1289/ehp.7192] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2004] [Accepted: 07/28/2004] [Indexed: 05/24/2023]
Abstract
We examined the interrelationships between phenotype of hepatic cytochrome P450 2A6 (CYP2A6), nephropathy, and exposure to cadmium and lead in a group of 118 healthy Thai men and women who had never smoked. Their urinary Cd excretion ranged from 0.05 to 2.36 microg/g creatinine, whereas their urinary Pb excretion ranged from 0.1 to 12 microg/g creatinine. Average age and Cd burden of women and men did not differ. Women, however, on average showed a 46% higher urinary Pb excretion (p < 0.001) and lower zinc status, suggested by lower average serum Zn and urinary Zn excretion compared with those in men. Cd-linked nephropathy was detected in both men and women. However, Pb-linked nephropathy was seen only in women, possibly because of higher Pb burden coupled with lower protective factors, notably of Zn (p < 0.001), in women compared with men. In men, Pb burden showed a negative association with CYP2A6 activity (adjusted beta = -0.29, p = 0.003), whereas Cd burden showed a positive association with CYP2A6 activity (adjusted beta = 0.38, p = 0.001), suggesting opposing effects of Cd and Pb on hepatic CYP2A6 phenotype. The weaker correlation between Cd burden CYP2A6 activity in women despite similarity in Cd burden between men and women is consistent with opposing effects of Pb and Cd on hepatic CYP2A6 phenotypic expression. A positive correlation between Cd-linked nephropathy (urinary N-acetyl-beta-D-glucosaminidase excretion) and CYP2A6 activity in men (r = 0.39, p = 0.002) and women (r = 0.37, p = 0.001) suggests that Cd induction of hepatic CYP2A6 expression and Cd-linked nephropathy occurred simultaneously.
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Samson WK, Baker JR, Samson CK, Samson HW, Taylor MM. Central neuropeptide B administration activates stress hormone secretion and stimulates feeding in male rats. J Neuroendocrinol 2004; 16:842-9. [PMID: 15500544 DOI: 10.1111/j.1365-2826.2004.01239.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Neuropeptide B (NPB) was identified to be an endogenous, peptide ligand for the orphan receptors GPR7 and GPR8. Because GPR7 is expressed in rat brain and, in particular, in the hypothalamus, we hypothesized that NPB might interact with neuroendocrine systems that control hormone release from the anterior pituitary gland. No significant effects of NPB were observed on the in vitro releases of prolactin, adrenocorticotropic hormone (ACTH) or growth hormone (GH) when log molar concentrations ranging from 1 pM to 100 nM NPB were incubated with dispersed anterior pituitary cells harvested from male rats. In addition NPB (100 nM) did not alter the concentration response stimulation of prolactin secretion by thyrotropin-releasing hormone, ACTH secretion by corticotropin-releasing factor (CRF) and GH secretion by GH-releasing hormone. However, NPB, when injected into the lateral cerebroventricle (i.c.v.) of conscious, unrestrained male rats, elevated prolactin and corticosterone, and lowered GH levels in circulation. The threshold dose for the effect on corticosterone and prolactin levels was 1.0 nmol, while that for the effect on GH release was 3.0 nmol NPB. Pretreatment with a polyclonal anti-CRF antiserum completely blocked the ability of NPB to stimulate ACTH release and significantly inhibited the effect of NPB on plasma corticosterone levels. NPB administration i.c.v. did not significantly alter plasma vasopressin and oxytocin levels in conscious rats. It did stimulate feeding (minimum effective dose 1.0 nmol) in sated animals in a manner similar to that of the other endogenous ligand for GPR7, neuropeptide W. We conclude that NPB can act in the brain to modulate neuroendocrine signals accessing the anterior pituitary gland, but does not itself act as a releasing or inhibiting factor in the gland, at least with regard to prolactin, ACTH and GH secretion.
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Mecke A, Lee I, Baker JR, Holl MMB, Orr BG. Deformability of poly(amidoamine) dendrimers. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2004; 14:7-16. [PMID: 15221586 DOI: 10.1140/epje/i2003-10087-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2003] [Indexed: 05/24/2023]
Abstract
Experimental data indicates that poly(amidoamine) (PAMAM) dendrimers flatten when in contact with a substrate, i.e. they are no longer spherical, but resemble flat disks. In order to better understand the deformation behavior of these branched polymers, a series of atomistic molecular dynamics simulations is performed. The resulting flattened dendrimer conformations are compared to atomic force microscopy (AFM) images of individual dendrimers at air/mica and water/mica interfaces. The ability of the polymers to deform is investigated as a function of dendrimer generation (2-5) and the required energies are calculated. Our modeling results show good agreement with the experimental AFM images, namely that dendrimers are highly flexible and capable of forming multiple interaction sites between most of their branch ends and the substrate. The deformation energy scales with dendrimer generation and does not indicate an increase in stiffness between generations 2 and 5 due to steric effects.
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Satarug S, Ujjin P, Vanavanitkun Y, Baker JR, Moore MR. Influence of body iron store status and cigarette smoking on cadmium body burden of healthy Thai women and men. Toxicol Lett 2004; 148:177-85. [PMID: 15041068 DOI: 10.1016/j.toxlet.2003.09.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Revised: 09/20/2003] [Accepted: 09/24/2003] [Indexed: 11/15/2022]
Abstract
The influence of cigarette smoking, body iron store status and gender on cadmium (Cd) body burden was examined in a group of 197 healthy Thais with overall mean age of 30.5 year (19-47 year). The lowest, geometric mean, and the highest urinary Cd excretion rate was 0.04, 0.46 and 3.84 microg/g creatinine, respectively. The prevalence of low iron stores (serum ferritin <20 microg/l) was 16% and 2% in women and men, respectively. All women (n = 99) were non-smokers, but they had the same Cd body burden as did men (n = 47) who on average smoked 8.7 cigarettes per day for 9 years. These women and men had 1.9-fold greater body Cd burden than did non-smoking men (t = 4, P < 0.001). In addition, the women Cd body burden was found to be inversely correlated with serum ferritin (r = -0.39, P < 0.001) and those with low iron stores showed a 3.4-fold greater Cd body burden than did women whose serum ferritin being between 101 and 200 microg/l (F = 6.2, P = 0.003, one-way ANOVA). In contrast, men's Cd body burden did not show a significant correlation with serum ferritin, but it did show a positive correlation with cumulative cigarette smoking index (r = 0.29, P = 0.02). Thus, iron status and cigarette smoking were found to be determinants of Cd body burden in young adult Thai women and men.
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Satarug S, Nishijo M, Ujjin P, Vanavanitkun Y, Baker JR, Moore MR. Effects of chronic exposure to low-level cadmium on renal tubular function and CYP2A6-mediated coumarin metabolism in healthy human subjects. Toxicol Lett 2004; 148:187-97. [PMID: 15041069 DOI: 10.1016/j.toxlet.2003.10.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Revised: 10/10/2003] [Accepted: 10/14/2003] [Indexed: 10/26/2022]
Abstract
Relationships between cadmium (Cd) body burden, kidney function and coumarin metabolism were investigated using two groups of 197 and 200 healthy Thais with men and women in nearly equal numbers. A mean age of one group was 30.5 years and it was 39.3 years for the other group. Of 397, 20 subjects (5%) excreted urine Cd between 1.4 microg/g and 3.8 microg/g creatinine and these subjects faced 10-15% increase in the probability of having abnormal urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG-uria). The prevalence of NAG-uria varied with Cd body burden in a dose-dependent manner (chi2 = 22, P < 0.008). Also NAG-nuria was one of the three kidney effect markers tested that showed the greatest strength of correlation with urine Cd in both men and women (r = 0.48, P < 0.001). In addition, urine Cd excretion of men and women showed a positive correlation (r = 0.46 to 0.54, P < 0.001) with urine 7-hydroxycoumarin (7-OHC) excretion which was used as a marker of liver cytochrome P450 2A6 (CYP2A6) enzyme activity. Urinary Cd excretion accounted for 25% of the total variation in urine 7-OHC excretion (P < 0.001). These data suggest that Cd may increase the expression of CYP2A6 in liver, resulting in enhanced coumarin metabolism in subjects with high Cd body burden.
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Dissanayake AM, Gamble G, Baker JR, Reed L. Diagnostic delays of adult patients admitted to hospital with diabetic ketoacidosis. Diabet Med 2004; 21:290-1. [PMID: 15008842 DOI: 10.1111/j.1464-5491.2004.01138.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jepson PD, Arbelo M, Deaville R, Patterson IAP, Castro P, Baker JR, Degollada E, Ross HM, Herráez P, Pocknell AM, Rodríguez F, Howie FE, Espinosa A, Reid RJ, Jaber JR, Martin V, Cunningham AA, Fernández A. Gas-bubble lesions in stranded cetaceans. Nature 2003; 425:575-6. [PMID: 14534575 DOI: 10.1038/425575a] [Citation(s) in RCA: 202] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chepurnov AA, Bakulina LF, Dadaeva AA, Ustinova EN, Chepurnova TS, Baker JR. Inactivation of Ebola virus with a surfactant nanoemulsion. Acta Trop 2003; 87:315-20. [PMID: 12875924 DOI: 10.1016/s0001-706x(03)00120-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hemorrhagic fever caused by Ebola virus (EBO) is a highly contagious infection. This necessitates that the contaminated instruments, clothes, and hospital premises must be completely disinfected. Nanoemulsions are a new form of disinfectant composed of detergents and vegetable oil suspended in water. The antiviral activity of nanoemulsion ATB has been investigated against EBO. The nanoemulsion was tested against two preparations of EBO (strain Zaire) obtained from Vero cell culture fluid (EBO-zc) and from blood of infected monkeys (EBO-zb). The nanoemulsion ATB was virucidal against both preparations of EBO, inactivating the purified virus within 20 min even when diluted 1:100 with the growth medium. Inactivation of the virus in tissue preparations was also complete, but required 1:10 dilutions with media or higher. After treatment with ATB (10 and 1% concentrations), no EBO was apparent even after two passages in Vero cell culture. These data indicate that the nanoemulsion is an effective disinfectant for EBO. Because of the excellent biocompatibility of nanoemulsions, studies are planned to determine whether the nanoemulsion-killed virus is suitable for developing a vaccine against EBO.
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Myaing MT, Ye JY, Norris TB, Thomas T, Baker JR, Wadsworth WJ, Bouwmans G, Knight JC, Russell PSJ. Enhanced two-photon biosensing with double-clad photonic crystal fibers. OPTICS LETTERS 2003; 28:1224-1226. [PMID: 12885028 DOI: 10.1364/ol.28.001224] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A double-clad photonic crystal fiber was used to improve detection efficiency over a standard single-mode fiber in a two-photon fluorescence detection scheme in which the dye was excited and the fluorescence was detected back through the same fiber.
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Baker JR, Satarug S, Edwards RJ, Moore MR, Williams DJ, Reilly PEB. Potential for early involvement of CYP isoforms in aspects of human cadmium toxicity. Toxicol Lett 2003; 137:85-93. [PMID: 12505434 DOI: 10.1016/s0378-4274(02)00382-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper investigates the possible link between non-workplace cadmium (Cd) exposure, cytochrome P450 expression and hypertension. We present results of our investigation into the relationships between liver and kidney Cd burdens and the abundance of the CYP isoform 4A11. Our data show associations between non-workplace Cd exposure and changes in the abundance of hepatic and renal cortical CYP4A11. In liver the levels of immunochemically detectable CYP4A11 were positively correlated with tissue Cd content while in contrast CYP4A11 abundance was inversely correlated with kidney Cd burden. These differences are most likely related to the different Cd burden of the tissues. These observations suggest the potential for involvement of Cd as a mediator of CYP4A11 expression in kidney cortex and indicate that elevations in kidney Cd content may be involved in hypertension via alteration of the expression of this particular isoform. Potential mechanisms by which Cd may alter CYP4A11 expression are discussed briefly.
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Satarug S, Baker JR, Urbenjapol S, Haswell-Elkins M, Reilly PEB, Williams DJ, Moore MR. A global perspective on cadmium pollution and toxicity in non-occupationally exposed population. Toxicol Lett 2003; 137:65-83. [PMID: 12505433 DOI: 10.1016/s0378-4274(02)00381-8] [Citation(s) in RCA: 647] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cadmium is a non-essential element that has high rates of soil to plant transference compared with other non-essential elements, and certain plant species accumulate large amounts of cadmium from low cadmium content soils. In this paper, levels of cadmium found in major food groups are highlighted together with cadmium levels found in liver and kidney samples from non-occupationally exposed populations. Data on human kidney cadmium levels identified recently, including the study in our own laboratory, are compared with older studies. Human-tissue cadmium contents showed large variations among individuals, but sources of the variation remain unknown. Exposure levels of 30-50 microg per day have been estimated for adults and these levels have been linked to increased risk of bone fracture, cancer, kidney dysfunction and hypertension. Increased mortality was found among individuals showing signs of cadmium renal toxicity compared with those without such signs, suggesting that renal toxicity may be an early warning of complications, sub-clinical or clinical morbidity.
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Hamouda T, Shih AY, Baker JR. A rapid staining technique for the detection of the initiation of germination of bacterial spores. Lett Appl Microbiol 2002; 34:86-90. [PMID: 11849500 DOI: 10.1046/j.1472-765x.2002.01047.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS We propose to apply the Wirtz-Conklin staining technique to evaluate spore germination. METHODS AND RESULTS Spores at different stages of germination were stained with modified spore stain (Wirtz-Conklin) and evaluated for staining properties. Bacillus spores suspended in deionized water, which does not support germination, stained greenish-blue. Spores suspended in germination enhancers that did not form bacilli stained pink, indicating the initiation of germination. Spores suspended in culture media, which promotes bacterial outgrowth, formed bacilli and were also stained pink. CONCLUSIONS Modified spore stain (Wirtz-Conklin) was found to be useful to detect the initiation of spore germination as early as 30 min following incubation in a germination environment. SIGNIFICANCE AND IMPACT OF THE STUDY This simple staining procedure is useful in detecting the initiation of germination of bacterial spores.
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Bretz JD, Mezosi E, Giordano TJ, Gauger PG, Thompson NW, Baker JR. Inflammatory cytokine regulation of TRAIL-mediated apoptosis in thyroid epithelial cells. Cell Death Differ 2002; 9:274-86. [PMID: 11859410 DOI: 10.1038/sj.cdd.4400965] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2001] [Revised: 08/30/2001] [Accepted: 09/27/2001] [Indexed: 01/12/2023] Open
Abstract
Death receptor-mediated apoptosis has been implicated in target organ destruction in chronic autoimmune thyroiditis. Depending on the circumstances, inflammatory cytokines such as IL-1, TNF and IFNgamma have been shown to contribute to either the induction, progression or inhibition of this disease. Here we demonstrate that the death ligand TRAIL can induce apoptosis in primary, normal, thyroid epithelial cells under physiologically relevant conditions, specifically, treatment with the combination of inflammatory cytokines IL-1beta and TNFalpha. In contrast, IFNgamma is capable of blocking TRAIL-induced apoptosis in these cells. This regulation of TRAIL-mediated apoptosis by inflammatory cytokines appears to be due to alterations of cell surface expression of TRAIL receptor DR5 and not DR4. We also show the in vivo presence of TRAIL and TRAIL receptors DR5 and DcR1 in both normal and inflamed thyroids. Our data suggests TRAIL-mediated apoptosis may contribute to target organ destruction in chronic autoimmune thyroiditis.
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Baker JR, Satarug S, Urbenjapol S, Edwards RJ, Williams DJ, Moore MR, Reilly PEB. Associations between human liver and kidney cadmium content and immunochemically detected CYP4A11 apoprotein. Biochem Pharmacol 2002; 63:693-6. [PMID: 11992637 DOI: 10.1016/s0006-2952(01)00905-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This present study was undertaken to assess potential effects of cadmium on CYP4A11 apoprotein in human liver and kidney as detected by Western blotting using a highly specific anti-peptide antibody. Liver and kidney cortex samples were autopsy specimens of 37 individuals (26 males and 11 females) whose ages ranged from 3 to 89 years. All were Caucasians who had not been exposed to cadmium in the workplace. Reduced CYP4A11 apoprotein levels were found in chronic hepatitis samples and in liver samples showing fatty changes. In contrast, increased CYP4A11 apoprotein levels were found in liver samples having higher cadmium content compared to the lower cadmium content samples. Increased CYP4A11 levels were also found in liver samples from female donors, compared to male donors; the difference being attributable to higher female liver cadmium burden. In distinction to liver, lowered CYP4A11 levels were seen in the kidney cortex samples which have high cadmium content. It is proposed here that the difference between the absolute cadmium burden of the liver and kidney samples may be responsible for the different patterns of expression of CYP4A11 in these two tissues. Further, since cadmium exposure may be associated with derangement in blood pressure control, it is interesting to note the possible relationship between altered CYP4A11-dependent production of arachidonic acid hydroxy and epoxy metabolites in kidney cortex and altered control of blood pressure. Our findings provide a possible link between these observations.
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Satarug S, Baker JR, Reilly PEB, Moore MR, Williams DJ. Cadmium levels in the lung, liver, kidney cortex, and urine samples from Australians without occupational exposure to metals. ARCHIVES OF ENVIRONMENTAL HEALTH 2002; 57:69-77. [PMID: 12071363 DOI: 10.1080/00039890209602919] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The authors undertook this study to assess levels of cadmium exposure in the general population. Samples of lung, liver, and kidney were obtained from 61 cadavers (43 males, 18 females; 2-89 yr of age, mean age = 38.5 yr) who died from accidental causes and who were subject to postmortem examinations at the John Tonge Centre for Forensic Sciences, Queensland Health Scientific Services, Brisbane, Australia, in 1997 and 1998. Samples of bladder urine were also obtained from 22 cadavers. Tissue and urine samples were analyzed for cadmium, zinc, and copper with inductively coupled plasm (ICP) mass spectrometry. The overall mean values for cadmium in the lung, liver, and kidney cortex samples were 0.13, 0.95, and 15.45 microg/gm wet tissue weight. The average renal cadmium level in subjects with high lung-cadmium levels (n = 13) was 6 microg/gm wet tissue weight higher than that of similarly aged subjects who had medium lung-cadmium levels (n = 30). In females, the average level of cadmium in the liver was 74% greater than in males, and the average liver cadmium in females with high lung-cadmium levels was 100% higher than in males in the same age range who had the same high lung-cadmium levels. Renal cadmium accumulation tended to be greater in females than in males who were in the same age range and who had similar lung-cadmium levels, a result that suggested that there was a higher absorption rate of cadmium in females. The mean value for a urinary cadmium excretion of 2.30 microg/gm creatinine was found in a subset of samples that had a mean age of 39 yr and a renal cortex cadmium concentration of 18.6 microg/gm wet tissue weight. Urinary cadmium excretion rates were correlated more strongly with lung and kidney cadmium content than with age or liver cadmium levels. The results suggest that urinary cadmium excretion may be increased in smokers and could provide some estimate of body cadmium burdens in future Australian epidemiological studies.
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Baker JR, Yardley JK, McCaul K. Characteristics of responding-, nonresponding- and refusing-parents in an adolescent lifestyle choice study. EVALUATION REVIEW 2001; 25:605-618. [PMID: 11729697 DOI: 10.1177/0193841x0102500602] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The acquisition of a random sample is one of the many methodological problems that arise when conducting research with adolescent populations. Frequently, due to ethical considerations associated with collecting data from adolescents, active parental consent procedures are required. The current study examined characteristics of parents who consented, refused consent, or did not respond to an active consent request for their children to participate in a large-scale study of adolescent lifestyle behaviors. Results indicated nonresponding-parents were more likely to be employed than consenting-parents. Further, differences were found for a number of attitudinal variables and about the importance of adolescent research. There were significant differences between refusing-parents, and consenting- and nonresponding-parents who were similar in their attitudes toward adolescent research. The findings suggest that nonresponding-parents are characteristically more similar to consenting-parents than to refusing-parents, which supports the use of passive consent procedures as a reasonable alternative to requiring active parental consent in adolescent research.
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Baker JR. Literature Alert.. Curr Allergy Asthma Rep 2001; 1:486-8. [PMID: 11892077 DOI: 10.1007/s11882-001-0056-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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