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Search Results: 1 - 10 of 3235 matches for " Irene Westbroek "
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Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania
Marnix de Zeeuw,Irene Westbroek,Martien van Oijen,Frans Witte
ZooKeys , 2013, DOI: 10.3897/zookeys.256.3871
Abstract: Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania, are described and illustrated. These species closely resemble each other. Their affinities to other zooplanktivorous haplochromines from Lake Victoria are discussed. Haplochromis argens sp. n., which featured under nicknames (mainly H. “argens”) in more than 50 papers, was caught both in the Mwanza Gulf and the Emin Pasha Gulf, whereas H. goldschmidti sp. n. was only found in the Emin Pasha Gulf. Of the latter species only males are available, but it seems unlikely that it represents a case of male colour polymorphism as several presumably unrelated characters differ in sympatry between the two species, suggesting that there is no gene flow. Statistical analysis revealed that the overall difference between the two species is greater than that between the populations from the two locations. Body depth of the two species in sympatry in the Emin Pasha Gulf was more similar than that of H. goldschmidti sp. n. and the allopatric population of H. argens sp. n. from the Mwanza Gulf, which may indicate an overall environmental effect. However, several measurements related to the width of snout and mouth differed more between the populations of the two species in sympatry than between the allopatric populations. In contrast to a group of zooplanktivorous species that recovered successfully after environmental changes in the lake, H. argens sp. n. is among a group that became extremely rare and probably is in danger of extinction; the conservation status of H. goldschmidti sp. n. is currently unknown.
Skeletal Effects of the Saturated 3-Thia Fatty Acid Tetradecylthioacetic Acid in Rats
Astrid Kamilla Stunes,Irene Westbroek,Reidar Fossmark,Rolf Kristian Berge,Janne Elin Reseland,Unni Syversen
PPAR Research , 2011, DOI: 10.1155/2011/436358
Abstract: This study explores the skeletal effects of the peroxisome proliferator activated receptor (PPAR)pan agonist tetradecylthioacetic acid (TTA). Rats, without (Study I) and with ovariectomy (OVX) or sham operation (Study II), were given TTA or vehicle daily for 4 months. Bone markers in plasma, whole body and femoral bone mineral density and content (BMD and BMC), and body composition were examined. Histomorphometric and biomechanical analyses (Study I) and biomechanical and μCT analyses (Study II) of the femur were performed. Normal rats fed TTA had higher femoral BMD and increased total and cortical area in femur compared to controls. The ovariectomized groups had decreased BMD and impaired microarchitecture parameters compared to SHAM. However, the TTA OVX group maintained femoral BMC, trabecular thickness in the femoral head, and cortical volume in the femoral metaphysis as SHAM. TTA might increase BMD and exert a light preventive effect on estrogen-related bone loss in rats. 1. Introduction Fatty acids are natural ligands for peroxisome proliferator activated receptors (PPAR) α, δ, and γ. Tetradecylthioacetic acid (TTA) is a saturated 16 carbon 3-thia synthetic fatty acid, which also acts as a PPARpan agonist. Studies have shown multifaceted effects of TTA in rodents. It induces mitochondrial fatty acid β-oxidation and causes reduced plasma levels of free fatty acids (FFA) and triglycerides (TG) in addition to improved insulin response, anti-inflammatory action and lowered oxidative stress [1–3]. The responses are qualitatively similar to the effects of n-3 fatty acids, but TTA seems to have a greater biological potency. A main determinant of the mechanism of action seems to be the non-β-oxidizability of TTA due to the sulphur atom in the third position in the carbon chain [4]. TTA is also found to attenuate dyslipidemia in male patients with type 2 diabetes mellitus [1]. Many of the effects of TTA in this study point in direction of PPARα as well as PPARδ activation, with a similar pattern of lipid lowering effects as observed in patients with impaired glucose tolerance after treatment with fenofibrate, which is a selective PPARα agonist [1, 5]. Studies in rodents also indicate that TTA acts through mechanisms that at least partly involve PPARα activation [2]. All PPAR subtypes are present in bone cells [6]. We and others have shown that PPARγ agonists have negative skeletal effects in rodents, by decreasing bone mass and deteriorating the architectural structure [7–11]. Increased fracture incidence has also been observed in patients with type 2
The peroxisome proliferator-activated receptor (PPAR) alpha agonist fenofibrate maintains bone mass, while the PPAR gamma agonist pioglitazone exaggerates bone loss, in ovariectomized rats
Astrid K Stunes, Irene Westbroek, Bj?rn I Gustafsson, Reidar Fossmark, Jan H Waarsing, Erik F Eriksen, Christiane Petzold, Janne E Reseland, Unni Syversen
BMC Endocrine Disorders , 2011, DOI: 10.1186/1472-6823-11-11
Abstract: Fifty-five female Sprague-Dawley rats were assigned to five groups. One group was sham-operated and given vehicle (methylcellulose), the other groups were ovariectomized and given vehicle, fenofibrate, Wyeth 14643 and pioglitazone, respectively, daily for four months. Whole body and femoral BMD were measured by dual X-ray absorptiometry (DXA), and biomechanical testing of femurs, and micro-computed tomography (microCT) of the femoral shaft and head, were performed.Whole body and femoral BMD were significantly higher in sham controls and ovariectomized animals given fenofibrate, compared to ovariectomized controls. Ovariectomized rats given Wyeth 14643, maintained whole body BMD at sham levels, while rats on pioglitazone had lower whole body and femoral BMD, impaired bone quality and less mechanical strength compared to sham and ovariectomized controls. In contrast, cortical volume, trabecular bone volume and thickness, and endocortical volume were maintained at sham levels in rats given fenofibrate.The PPARalpha agonist fenofibrate, and to a lesser extent the PPARaplha agonist Wyeth 14643, maintained BMD and bone architecture at sham levels, while the PPARgamma agonist pioglitazone exaggerated bone loss and negatively affected bone architecture, in ovariectomized rats.Peroxisome proliferator-activated receptors (PPARs) are ligand-activated nuclear receptors, and exist as three different subtypes in mammals (PPARα, PPARδ and PPARγ (with isoforms γ1, γ2 and γ3)) [1,2]. All PPARs form heterodimers with the 9-cis-retinoic acid receptor (RXR). PPARs are ubiquitously expressed, but with a tissue specific distribution, and are involved in the regulation in a broad specter of biological processes, particularly in carbohydrate and lipid homeostasis [2-5]. Endogenous ligands for PPARs include eicosanoids, fatty acids and fatty acid derivatives [3].Because of their metabolic actions, PPARs (as yet preferentially PPARα and γ ) have become major drug targets [6]. Wyeth 14643 (pi
Interactions of Lactobacilli with Pathogenic Streptococcus pyogenes
Mark L. Westbroek,Crystal L. Davis,Lena S. Fawson,Travis M. Price
Infectious Diseases in Obstetrics and Gynecology , 2010, DOI: 10.1155/2010/289743
Abstract: Objective. To determine whether (1) a decreased concentration of Lactobacilli allows S. pyogenes to grow; (2) S. pyogenes is able to grow in the presence of healthy Lactobacillus concentrations; (3) S. pyogenes is capable of inhibiting Lactobacilli. Methods. One hundred fifty patient samples of S. pyogenes were mixed with four different concentrations of L. crispatus and L. jensenii. Colony counts and pH measurements were taken from these concentrations and compared using t-tests and ANOVA statistical analyses. Results. Statistical tests showed no significant difference between the colony counts of S. pyogenes by itself and growth when mixed with Lactobacilli, and no significant difference between the colony counts of S. pyogenes in the four different concentrations of Lactobacilli. Conclusion. The statistical data representing the growth of these two organisms suggests that Lactobacilli did not inhibit the growth of S. pyogenes. Also, S. pyogenes did not inhibit the growth of Lactobacilli. 1. Introduction Lactobacillus bacteria (Lactobacilli) are large Gram positive rods that exist as nonpathogenic microbiota. Lactobacilli have been extensively studied due to their remarkable ability to inhibit the growth of other organisms through bactericidal activity and by producing lactic acid as a byproduct of metabolism [1, 2]. Lactic acid production, production of bacteriocins, and the production of hydrogen peroxide have led to an abundance of research involving the ability of Lactobacilli to inhibit pathogens. Lactobacillus species have proven effective at inhibiting the growth of bacterial and fungal pathogens which commonly cause vaginosis. Lactobacillus species, specifically L. crispatus and L. jensenii, are the predominant flora in the vagina, and thus minimize opportunities for infection [3–8]. Several common pathogens that Lactobacilli inhibit are: Candida albicans, Escherichia coli (including E. coli O157:H7); and Neisseria gonorrhoeae [1, 2, 5–9]. Due to their ability to inhibit other organisms, Lactobacilli are commonly used for probiotic therapy to enhance intestinal microbiota, as well as to treat vaginosis. The principle of this treatment is to increase the concentration of Lactobacilli, which will inhibit pathogens and allow the body’s immune system to overcome the infection without the use of antimicrobials [8, 9]. Streptococcus pyogenes, often referred to as Group A strep, is a Gram positive coccus which tends to group together in chains. S. pyogenes causes the infection commonly known as “strep throat” and is the cause of 90% of bacterial
The role that oilseeds, including new hi-oleic varieties can play in improving the profile of fat intake by the UK population  [PDF]
Janice Irene Harland
Agricultural Sciences (AS) , 2014, DOI: 10.4236/as.2014.53024

The production in the EU of the oilseeds, rapeseed and sunflower, has increased dramatically over the last 20 years. Much of the oil produced after crushing is used for culinary purposes; this enhanced intake of vegetable oil has led to a substantial change of fatty acid (FA) supply. This has been conclusively demonstrated by taking the UK oil supply data and by use of the FA profile of the key oils converting the supply data into a FA profile of the UK market place for 2008-2012. The most marked changes are a reduction in saturated fat (SFA) and an increase in monounsaturated fatty acids (MUFA) available for consumption. Furthermore the introduction of varieties of hi-oleic sunflower oil can further affect the market FA profile. The fat profiles of rapeseed and sunflower oils are considered healthy and they can have a positive impact when included in the diet, particularly as a replacement for oils or fats rich in SFA. In the UK and much of Europe, adult SFA intake continues to exceed recommendations. While reductions in the UK population’s SFA intake have occurred over the last 20 years, these are modest and it may be timely to identify ways in which SFA intake can be further reduced. To do this, the UK market FA supply data has been analysed alongside the profile of FA intake from adults recording their intake in national dietary surveys in order to identify if the market supply affects overall FA consumption. There is an indication that market oil supply is reflected in adults dietary intake of the main groups of FA. Consequently changes made to the oil profile of oilseeds by plant breeders and use of the resulting healthier oils by food manufacturers could have important roles to play in helping adults to achieve the recommended intake of SFA and also improve the overall fat quality in their diet leading to enhanced long-term health and well-being. Thus changes made in pri

The Relationship between Access to Mass Media and HIV/AIDS Related Knowledge, Beliefs and Behaviours in Kenya  [PDF]
Irene Muli, Stephen Lawoko
Psychology (PSYCH) , 2014, DOI: 10.4236/psych.2014.57084

Aim: We scrutinized the association between access to mass media and HIV/AIDS related knowledge, beliefs and behaviours in Kenya. Methods: Data on a representative sample of Kenyan women between 15 - 30 years of age (n = 3909) was retrieved from the Kenyan demographic and health survey (DHS 2008) and analyzed using Chi-square tests and binary logistic regression. Results: Media use was common with over 70% of participants using radio at least once a week. Between 3% - 30% of participants had poor to inadequate knowledge/beliefs about HIV/AIDS, with variations depending on demographic and social factors such as age, education, literacy, wealth and residential area. HIV/AIDS knowledge, beliefs and behaviours were associated with exposure to media, even after control for possible co-variation with social and demographic factor. Conclusion: Despite wide exposure to media among young Kenyan women, substantial proportions have poor to inadequate knowledge of the aetiology, risk/protective factors and control measures of HIV/AIDS. Yet, such knowledge was positively associated with media use. Media thus could ideally be used to implement a comprehensive awareness campaign in the general population about the aetiology, risk/protective factors and control measures in HIV/AIDS.

Association of the Hermansky-Pudlak syndrome type-3 protein with clathrin
Amanda Helip-Wooley, Wendy Westbroek, Heidi Dorward, Mieke Mommaas, Raymond E Boissy, William A Gahl, Marjan Huizing
BMC Cell Biology , 2005, DOI: 10.1186/1471-2121-6-33
Abstract: Clathrin was co-immunoprecipitated by HPS3 antibodies from normal but not HPS3 null melanocytes. Normal melanocytes expressing a GFP-HPS3 fusion protein demonstrated partial co-localization of GFP-HPS3 with clathrin following a 20°C temperature block. GFP-HPS3 in which the predicted clathrin-binding domain of HPS3 was mutated (GFP-HPS3-delCBD) did not co-localize with clathrin under the same conditions. Immunoelectron microscopy of normal melanocytes expressing GFP-HPS3 showed co-localization of GFP-HPS3 with clathrin, predominantly on small vesicles in the perinuclear region. In contrast, GFP-HPS3-delCBD did not co-localize with clathrin and exhibited a largely cytoplasmic distribution.HPS3 associates with clathrin, predominantly on small clathrin-containing vesicles in the perinuclear region. This association most likely occurs directly via a functional clathrin-binding domain in HPS3. These results suggest a role for HPS3 and its protein complex, BLOC-2, in vesicle formation and trafficking.Hermansky-Pudlak syndrome (HPS [MIM: 203300]) is an autosomal recessive disorder of vesicle biogenesis resulting in the dysfunction of lysosome-related organelles such as melanosomes and platelet dense bodies [1-4]. Affected patients have oculocutaneous albinism presenting as congenital nystagmus, reduced visual acuity, and varying degrees of hypopigmentation of the skin, hair, and irides [5-7]. In addition, a platelet storage pool deficiency, manifesting as absence of platelet dense bodies, causes loss of the secondary aggregation response [2,8,9]. Clinically, this results in easy bruising and epistaxis in childhood, prolonged bleeding during dental extractions and surgeries, and excessive menstrual and postpartum bleeding [9]. Some HPS patients also develop granulomatous colitis or a fatal pulmonary fibrosis [9,10].To date, seven genes have been identified as causes of human HPS subtypes (HPS-1 through HPS-7), and other genes identified in mouse models of HPS may also cause
The Use of “Scalp Block” in Pediatric Patients  [PDF]
Joseph Sebeo, Irene P. Osborn
Open Journal of Anesthesiology (OJAnes) , 2012, DOI: 10.4236/ojanes.2012.23017
Abstract: Infiltration of the nerves of the scalp with local anesthetics is used in adults for a variety of head and neck procedures and craniotomies with many benefits, from hemodynamic stability to reduced postoperative pain. We here succinctly review the current evidence for “scalp block” in pediatric patients.
A Liquid Chromatography Assay for the Simultaneous Quantification of Piperacillin and Ciprofloxacin in Human Plasma and Dialysate in Critically Ill Patients Undergoing Continuous Renal Replacement Therapy  [PDF]
Florian Scheer, Irene Kr?mer
International Journal of Analytical Mass Spectrometry and Chromatography (IJAMSC) , 2014, DOI: 10.4236/ijamsc.2014.22005

Piperacillin/tazobactam and ciprofloxacin are often used in combination as initial empiric anti-biotic therapy in critical ill patients. Especially in patients undergoing continuous renal replacement therapy (CRRT) the pharmacokinetics of antimicrobial agents can be highly variable. In order to avoid under- or overdosage of antibiotics therapeutic drug monitoring (TDM) is highly re-commendable. Based on two known HPLC assays for piperacillin a new method in combination with solid phase extraction (SPE) for the simultaneous determination of piperacillin and ciprofloxacin was developed. Method validation was performed according to the EMA guideline on validation of bioanalytical methods. The HPLC column used was a Perfect Bond ODS-HD C18 analytical column (100 mm × 4.6 mm i.d., particle size 5 μm), equipped with a guard column (10 mm × 4.6 mm, particle size 5 μm) containing the same packing material. Detection wavelength was set at 228 nm for piperacillin and benzylpenicillin was used as internal standard (IS). Ciprofloxacin was determined at two wavelengths (280 nm, 315 nm). This newly developed HPLC method in combination with SPE-extraction allows an accurate, precise, specific and efficient determination of piperacillin and ciprofloxacin in biological matrices. Results allow the calculation of all relevant pharmacokinetic data for critically ill patients undergoing CRRT and the optimization of dosing and TDM.

Determinants of Loan Defaults in Some Selected Credit Unions in Kumasi Metropolis of Ghana  [PDF]
Edward Yeboah, Irene Mirekuah Oduro
Open Journal of Business and Management (OJBM) , 2018, DOI: 10.4236/ojbm.2018.63059
Credit Unions play a pivotal role in the Microfinance Industry in Ghana. They are not only deeply rooted in financial intermediation but also provide favorable terms and conditions in financial products and services to their members compared to banks and other financial institutions. The sustainability of Credit Unions has been threatened by the incidence of loan defaults or non-performing loans. The diagnostics of the causes of loan defaults in Credit Unions become paramount toward sound credit risk management practices. The study relied on primary data. Purposive sampling technique was applied to select 244 Credit Union members. Questionnaires were used for data collection and logistic regression model was adopted. The study utilized Statistical Product and Service Solution (SPSS v. 20) and Stata (v.14) as statistical tools for data analysis. The results reveal that education, loan diversion, monitoring, marital status and income are significant factors that influence loan default. Thus, credit education should be intensified and that effective loan monitoring should be vigorously pursued. Additionally, loan appraisal systems should be robust with the application and development of credit scoring systems that will factor in key variables of loan default.
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