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Marinus J, Visser M, Verwey NA, Verhey FRJ, Middelkoop HAM, Stiggelbout AM, van Hilten JJ. Assessment of cognition in Parkinson's disease. Neurology 2004; 61:1222-8. [PMID: 14610124 DOI: 10.1212/01.wnl.0000091864.39702.1c] [Citation(s) in RCA: 219] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To develop a short, practical instrument that is sensitive to the specific cognitive deficits in Parkinson's disease (PD) for comparing groups in research situations and for assessing change in cognitive functioning over time. METHODS A literature search was conducted to identify the most frequently affected cognitive domains in PD and to select candidate items for the initial scale. This scale was tested in 85 patients and 75 age-, education-, and sex-matched control subjects. Items that met predefined criteria for data quality, reproducibility, and discriminative properties were included in the final scale. RESULTS The final scale, the SCOPA-COG (SCales for Outcomes of PArkinson's disease-cognition), consists of 10 items with a maximum score of 43, with higher scores reflecting better performance. The test-retest reliability of the total score was 0.78 (intraclass correlation coefficient) and ranged from 0.40 to 0.75 for individual items (weighted kappa). Cronbach's alpha was 0.83. Construct validity of the scale was supported by the expected correlations with the CAMCOG (Cambridge Cognitive Examination) and the Mini-Mental State Examination (MMSE) and by differences found between groups of participants classified by dementia status and between patients grouped by disease severity. The scale showed a clear trend toward lower cognition scores for patients with more advanced PD. The coefficient of variation of the SCOPA-COG was higher than that of the CAMCOG or the MMSE, indicating a better ability to detect differences between individuals. CONCLUSION The SCOPA-COG is a short, reliable, and valid instrument that is sensitive to the specific cognitive deficits in PD.
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Mitchell D, Haan MN, Steinberg FM, Visser M. Body composition in the elderly: the influence of nutritional factors and physical activity. J Nutr Health Aging 2003; 7:130-9. [PMID: 12766789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
BACKGROUND Controversy exists regarding the relative contribution of diet and exercise to body composition. Few studies have examined these associations in the elderly, where changes occur in the body fat to muscle ratio. OBJECTIVE The primary objective of this paper is to determine whether energy intake or physical activity are associated with body composition. Secondly, to investigate whether specific macronutrients are associated with fat or lean tissue. DESIGN Data (n= 1404) for this cross-sectional analysis were collected from a population-based sub-sample of elderly enrollees in the Cardiovascular Health Study (CHS). Dietary intake and physical activity were assessed by questionnaires. Body composition was measured by Dual Energy X-ray Absorptiometry (DEXA). Linear regression models were used to assess the associations of diet and activity with body composition. RESULTS Total energy intake was not associated with any of the body composition measures. Higher dietary saturated fat was associated with higher percent body mass as fat and trunk fat in both sexes (p<0.01), and in men other dietary fats were associated with body fat. In women, distance walked was inversely associated with fat masses even after adjustment for pace of walking. In both sexes, faster pace of walking was associated with lower body and fat mass (p<0.01). Lean muscle mass was not associated with physical activity or dietary intakes. CONCLUSION Physical activity and dietary fat intake in this the elderly population were more closely associated with body fat mass than was total energy intake.
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Rehbein S, Visser M, Rohrdorf, Lutz W. Erstnachweis vonSpiculopteragia houdemeri (Schwartz, 1926) (Nematoda, Trichostrongylidae, Ostertagiinae) außerhalb Asiens bei Sikahirschen (Cervus nippon) in Deutschland. EUR J WILDLIFE RES 2003. [DOI: 10.1007/bf02189738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rehbein S, Visser M, Winter R, Trommer B, Matthes HF, Maciel AE, Marley SE. Productivity effects of bovine mange and control with ivermectin. Vet Parasitol 2003; 114:267-84. [PMID: 12809753 DOI: 10.1016/s0304-4017(03)00140-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A randomised block design study was conducted to evaluate the effects of mange on cattle. Twenty-four Simmentaler Fleckvieh bulls were formed into eight replicates of three bulls based on Day -56 body weight (288-414 kg). Within replicates bulls were randomly allocated to groups G1: uninfested control, G2: infested control or G3: infested, treated with 0.2mg ivermectin/kg (1% ivermectin injection; IVOMEC, Merial) on Day 0. The G2 and G3 bulls were infested with Sarcoptes/Chorioptes mites on Days -56 and -49. Feed consumption was recorded daily throughout the study (Days -56 to 56). Body weights were measured and serum samples collected. Mites were counted at bi-weekly intervals from Day -14 on. The carcasses of the bulls and the leather produced from their hides were evaluated. Differences between variables were declared significant if P</=0.05. All G2 and G3 bulls became infested. No Sarcoptes or Chorioptes mites were detected on the G3 bulls after Day 14 or Day 28, respectively, whereas G2 bulls maintained infestation throughout the study. From Days -42 to 0, anti-Sarcoptes antibody levels in the two infested groups increased linearly, while levels in the uninfested G1 remained near zero. From Day 14 to Day 56, antibody levels in G2 continued to increase and those in G3 decreased (P</=0.05). From Days -56 to 0, G1 had significantly greater mean weight gain (94.0 kg) than the infested G2 and G3 (76.1 and 75.9 kg). During Days 0-56, G3 gained significantly more weight (90.4 kg) than G2 (58.8 kg), while G1 gained 76.0 kg, not significantly different from either G2 or G3. During Days -56 to 0, the feed conversion efficiency (kg gain/kg feed) of the infested G2 and G3 was significantly lower than that of the uninfested G1; during the 56 days following treatment, feed conversion efficiency of G3 was significantly higher than that of G2, while the uninfested G1 was intermediate. Carcass weight of G2 was significantly lower than those of G1 and G3, which did not differ significantly. Carcass yield, rib eye area and weight of kidney fat of the uninfested G1 were significantly greater than those of G2 and G3. Weights of the adrenal glands, prescapular and precrural lymph nodes were significantly higher for the infested G2 than for the other two groups. Significantly less of leather area from the infested G2 was of usable quality than of the leathers from the uninfested G1 or the infested, treated G3, and the leathers from G2 showed significantly more severe gouging or etching than leathers from the two other groups.
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Visser M, Hogeman PHG, van Vught AJ, Révész T, Wolfs TFW. [Fulminating pneumococcal septicemia in a 2 year old child with sickle cell anemia]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2003; 147:454-6. [PMID: 12666518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
A 2-year-old boy known with homozygous sickle cell anaemia became acutely ill at home. Despite intensive care, he died a few hours later due to pneumococcal septicaemia. In young children with homozygous sickle cell anaemia, spleen function is already severely impaired in childhood due to haemolysis and frequent vaso-occlusive episodes. These children therefore have an elevated susceptibility to severe invasive infections with encapsulated bacteria. Vaccination against pneumococci at-2 years of age, re-vaccination every 3-5 years, and antibiotic prophylaxis until 5 years of age, and thereafter with possible infections, are therefore necessary.
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van Felius I, Bosscha K, Verheem A, Harmsen W, Visser M, van Dijk J, van de Gaag I, Gooszen H, Akkermans L. Bacterial overgrowth and translocation in an experimental pancreatitis model. Br J Surg 2002. [DOI: 10.1046/j.1365-2168.2000.01544-30.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Background
A combination of secretory hyperstimulation and transduodenal intraductal bile acid exposure results in homogeneous pancreatitis with graded severity in a rat model. The model was modified by using an exteriorized common bile duct (CBD) as ductal infusion port while keeping the integrity of the gut intact. The objective was to determine whether bacterial translocation (BT) is present and relates to small bowel bacterial overgrowth (SBBO).
Methods
Fifty rats were divided into four groups: group 1, mild pancreatitis (intravenous caerulein); group 2, control (intravenous saline); group 3, necrotic pancreatitis (intravenous caerulein, intraductal glycodeoxycholic acid); and group 4, control (intravenous and intraductal saline). During infusion the CBD was clamped just above the papilla of Vater. Three days later samples from peripheral blood, peritoneal fluid and abdominal organs were harvested for quantitative microbial culturing. The splenic portion of the pancreas was removed for histopathological analysis.
Results
Histological examination showed minimal oedema in groups 2 and 4; group 1 was characterized by acinar vacuolization and group 3 had a combination of acinar necrosis with inflammation. BT to one or more abdominal organs took place. The difference in incidence of translocation between group 1 (six of 14) and group 2 (none of eight) was significant (P < 0·05). Furthermore, there was a significant difference in translocation between group 3 (six of eight) and group 4 (one of six) (P < 0·05), and in duodenal total bacterial counts between groups 3 and 4 (P < 0·05). Gram-negative rods and anaerobic bacterial counts were different between group 3 (mean(s.d.) 2·46(0·88)) and group 4 (0) (P < 0·05). However, total bacterial growth in the ileum did not differ significantly between groups.
Conclusion
In this pancreatitis model, without biliary obstruction, bacterial overgrowth of the duodenum occurred, accompanied by BT. Colonic bacteria were predominantly involved. This model offers the possibility of studying the relationship between SBBO, BT and the pathogenesis of necrotic (infected) pancreatitis.
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Karasik D, Rosen CJ, Hannan MT, Broe KE, Dawson-Hughes B, Gagnon DR, Wilson PWF, Visser M, Langlois JA, Mohan S, Kiel DP. Insulin-like growth factor binding proteins 4 and 5 and bone mineral density in elderly men and women. Calcif Tissue Int 2002; 71:323-8. [PMID: 12202958 DOI: 10.1007/s00223-002-1002-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2002] [Accepted: 03/27/2002] [Indexed: 11/28/2022]
Abstract
Insulin-like growth factor-1 (IGF-I) plays a central role in the maintenance of bone mass. To test whether two major IGF-I binding proteins, IGFBP-4 and IGFBP-5, are related to bone mineral density (BMD), we studied a sample of the Framingham Offspring Cohort participants (99 men and 101 women, ages 60-87). Serum levels of IGF-I, IGFBP-4, and IGFBP-5 were measured by previously validated radioimmunoassays (CVs approximately 10%). BMDs of the proximal femur and lumbar spine were measured using a Lunar DPX-L densitometer. In males, but not females, IGF-I and IGFBP-5 were inversely associated with age (r = 0.34 and r = -0.28, respectively; P <0.01), while IGFBP-4 levels were positively associated with age (P <0.01). Multivariate means for BMD (adjusted for age, body mass index, height, smoking, and in women, estrogen use) were computed across quartiles of IGFBP-4 and IGFBP-5 and IGFBP-4/IGFBP-5 ratio. In women, but not men, IGFBP-5 was positively associated with femoral neck BMD (P = 0.03), however, after statistical adjustment for IGF-I, this association was no longer significant. No other associations were observed for BMD at any other site. Further study is necessary for elucidation of the gender differences in the possible influence of IGF system components on bone mass.
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Rehbein S, Visser M. Efficacy of ivermectin delivered via a controlled-release capsule against small lungworms (Protostrongylidae) in sheep. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2002; 49:313-6. [PMID: 12420864 DOI: 10.1046/j.1439-0450.2002.00576.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To evaluate the efficacy of an ivermectin controlled-release capsule (CRC), which delivers 1.6 mg ivermectin per day intraruminally for 100 days to sheep weighing 40-80 kg (IVOMEC Maximizer CR Capsule for adult sheep, Merial), against small lungworms two studies with 48 naturally infected adult female Merino Landrace sheep were conducted. The sheep were allocated by restricted randomization based on bodyweight to untreated controls or received an ivermectin CRC. Eight sheep per group were necropsied 35, 70 or 105 days post-treatment. Lungworms were recovered by dissection or peptic digestion of the lungs. Baermann/Wetzel technique was used for faecal lungworm larval counts at weekly intervals. The efficacy of treatment was 100% against Dictyocaulus filaria and Protostrongylus rufescens (P < 0.05) at each necropsy day. The efficacy against Protostrongylus brevispiculum, Cystocaulus ocreatus and Neostrongylus linearis increased from 35 to 105 days after administration of the CRC and was found to be 100% (P < 0.01), 96.6% (P < 0.01) or 99% (P < 0.01), respectively, at 105 days post-treatment. The reductions of Muellerius capillaris counts varied and were 96.2% (P < 0.05) at 70 days post-treatment and 44.6% (P > 0.1) at 105 days post-treatment. Faecal lungworm larvae disappeared nearly completely from at least 3 weeks after the ivermectin CRC administration for all protostrongylid species including M. capillaris so that pasture infectivity will be subsequently significantly reduced.
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Snijder MB, Visser M, Dekker JM, Seidell JC, Fuerst T, Tylavsky F, Cauley J, Lang T, Nevitt M, Harris TB. The prediction of visceral fat by dual-energy X-ray absorptiometry in the elderly: a comparison with computed tomography and anthropometry. Int J Obes (Lond) 2002; 26:984-93. [PMID: 12080454 DOI: 10.1038/sj.ijo.0801968] [Citation(s) in RCA: 196] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2001] [Revised: 11/16/2001] [Accepted: 11/28/2001] [Indexed: 11/08/2022]
Abstract
INTRODUCTION Effective methods for assessing visceral fat are important to investigate the role of visceral fat for the increased health risks in obesity. Techniques for direct measurement of soft tissue composition such as CT or MRI are expensive, time-consuming or require a relatively high radiation dose. Simple anthropometric methods, such as waist-to-hip ratio, waist circumference or sagittal diameter are widely used. However, these methods cannot differentiate between visceral and subcutaneous fat and are less accurate. The aim of the present study is to investigate whether the dual-energy X-ray absorptiometry (DXA) method, possibly combined with anthropometry, offers a good alternative to CT for the prediction of visceral fat in the elderly. METHODS Subjects were participants in the Health ABC-study, a cohort study of black and white men and women aged 70-79, investigating the effect of weight-related health conditions on disablement. Total body fat and trunk fat were measured by DXA using a Hologic QDR 1500. A 10 mm CT scan at the L4-L5 level was acquired to measure visceral fat and total abdominal fat. Weight, height, sagittal diameter and waist circumference were measured using standard methods. Fat in a manually defined DXA subregion (4 cm slice at the top of iliac crest) at the abdomen was calculated in a sub-group of participants (n=150; 50% male; 45.3% Afro-American/54.7% Caucasian, age 70-79 y). This subregion, the standard trunk region and total fat were used as indicators of visceral fat. RESULTS Total abdominal fat by DXA (subregion) was strongly correlated with total abdominal fat by CT (r ranging from 0.87 in white men to 0.98 in black women). The DXA subregion underestimated total abdominal fat by 10% compared to the CT slice. The underestimation by DXA was seen especially in people with less abdominal fat. The association of visceral fat by CT with the DXA subregion (r=0.66, 0.78, 0.79 and 0.65 for white and black men and women, respectively) was comparable with the association of the CT measure with the sagittal diameter (r=0.74, 0.70, 0.84 and 0.68). Combining DXA measurements with anthropometry gave only limited improvement for the prediction of visceral fat by CT compared to univariate models (maximal increase of r(2) 4%). CONCLUSION DXA is a good alternative to CT for predicting total abdominal fat in an elderly population. For the prediction of visceral fat the sagittal diameter, which has a practical advantage compared to DXA, is just as effective.
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Rehbein S, Visser M, Winter R. Examination of faecal samples of horses from Germany and Austria. PFERDEHEILKUNDE 2002. [DOI: 10.21836/pem20020502] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Pluijm SM, Visser M, Smit JH, Popp-Snijders C, Roos JC, Lips P. Determinants of bone mineral density in older men and women: body composition as mediator. J Bone Miner Res 2001; 16:2142-51. [PMID: 11697812 DOI: 10.1359/jbmr.2001.16.11.2142] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study aimed to assess the relative importance of several determinants of bone mineral density (BMD) and to examine to what extent these potential determinants influence total hip BMD through body composition. The study population consisted of 522 participants (264 women and 258 men) of the Longitudinal Aging Study Amsterdam (LASA), aged 65 years and over, and living in Amsterdam and its vicinity. BMD of the total hip was measured using dual-energy X-ray absorptiometry (DXA). Potential determinants of BMD were age, weight change since age 25 years, lifestyle factors, chronic diseases, medication use, and hormonal factors. Potential mediators between the possible determinants and BMD were two measures of body composition: fat mass (FM) and appendicular muscle mass (AMM). Multiple regression analyses including all potential determinants in one model without body composition identified age, weight change, walking activity, and sex hormone-binding globulin (SHBG) as independent determinants for total hip BMD in women. In men, current smoking, participation in sports, and parathyroid hormone (PTH) concentration were independently associated with total hip BMD. When total hip BMD was regressed on the potential determinants and each measure of body composition, it appeared that FM, and to a lesser extent, muscle mass (MM), were independently related to BMD. In women, adjustment for FM reduced the strength of the associations of weight change, walking activity, and SHBG with total hip BMD. Adjustments for MM did not influence the associations between the determinants and BMD. In men, neither FM nor MM appeared to play a mediating role between the determinants and BMD. It can be concluded that (1) FM and MM are strong independent determinants of total hip BMD and that (2) FM possibly plays a mediating role in the association of weight change, walking activity, and SHBG with total hip BMD in women.
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Yee AJ, Fuerst T, Salamone L, Visser M, Dockrell M, Van Loan M, Kern M. Calibration and validation of an air-displacement plethysmography method for estimating percentage body fat in an elderly population: a comparison among compartmental models. Am J Clin Nutr 2001; 74:637-42. [PMID: 11684532 DOI: 10.1093/ajcn/74.5.637] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The use of hydrostatic weighing (HW) to measure body composition in the elderly can be difficult and is based on the assumption of constancy of body compartments. OBJECTIVE We calibrated and validated a new air-displacement plethysmography (AP) method for measuring body composition in the elderly. DESIGN A 4-compartment equation for calculating percentage body fat (%BF) that used body density (D(b)), total body water, and bone mineral content was used as the criterion for evaluating %BF estimated by the 2- and 3-compartment models. D(b) was measured by HW [D(b(HW))] and by use of the AP instrument [D(b(AP))] in 30 elderly men and 28 elderly women aged 70-79 y. RESULTS D(b(AP)) was not significantly different from D(b(HW)). However, analysis of variance showed a significant two-way interaction between sex and compartment model (P < 0.02), indicating that the comparisons between the sexes were different across all compartment models. The %BF calculated for the women was significantly higher than that calculated for the men by both HW and AP and for all compartment models. CONCLUSION Our data indicate that D(b(AP)) was not significantly different from D(b(HW)). Although differences were seen in %BF between the sexes, we observed no significant differences among the compartment models within each sex for this group of older individuals.
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Casellas JM, Visser M, Mac Dougall N, Coco B, Tomé G, Gliosca L. [Multicenter study in southern South America of the in vitro activity of telithromycin in strains with defined resistance phenotypes isolated from community-acquired respiratory infections]. REVISTA ESPANOLA DE QUIMIOTERAPIA : PUBLICACION OFICIAL DE LA SOCIEDAD ESPANOLA DE QUIMIOTERAPIA 2001; 14:269-74. [PMID: 11753448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Telithromycin was the first ketolide to be approved in Europe and is in the approval process in the United States. It is structurally related to the macrolides; it has a keto group in the C3 position rather than cladinose. A carbamate group is also present at C11-C12. As a result, it has a reduced induction of the MLSB resistance mechanism (erm gene), it is not affected by the flux mechanism (mef gene), it has higher stability at low pH and has increased intrinsic activity compared with clarithromycin and azithromycin. Phase III studies have shown telithromycin to be effective in the treatment of community-acquired upper and lower respiratory tract infections. Its long half-life allows for oral once-daily dosing. From a pharmacokinetic point of view, its activity has been shown to be AUC(24h)/MIC dependent. It is active against bacteria involved in atypical pneumonia. The aim of our study was to determine the activity of telithromycin in isolates with defined resistance phenotypes obtained from community-acquired respiratory tract infections. Twelve centers in Argentina, Chile, Paraguay and Uruguay participated in the study. Each center collected three strains of the following species and resistance patterns: S. pyogenes, S. pneumoniae with resistance or intermediate resistance to oxacillin, erythromycin-resistant S. pneumoniae, clindamycin-resistant S. pneumoniae, oxacillin-susceptible S. aureus, erythromycin-resistant S. aureus, ampicillin-susceptible and -resistant M. catarrhalis and H. influenzae. Agar diffusion susceptibility tests with NeoSensitabs tablets (Rosco, Denmark) were carried out at each center. Isolates were sent to the coordinating center, where MICs were determined using agar microdilution and the Seppala test was used to determine the resistance mechanism to macrolides. The 327 isolates received were susceptible to telithromycin. Eighty percent of the erythromycin-resistant S. pneumoniae isolates were likely resistant due to a flux mechanism, and all those resistant to clindamycin were resistant due to the erm inducible mechanism. Only 20 out of 36 strains of clindamycin-resistant S. pneumoniae and 25 of the 36 ampicillin-resistant H. influenzae strains could be collected, thereby showing that these resistance patterns are less common in the participating South American countries than in other areas. The in vitro activity of telithromycin suggests that it is a promising antibacterial drug for the treatment of community-acquired respiratory tract infections.
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Hegeman P, Christmann X, Visser M, Braat J. Experimental study of a shearing interferometer concept for at-wavelength characterization of extreme-ultraviolet optics. APPLIED OPTICS 2001; 40:4526-4533. [PMID: 18360493 DOI: 10.1364/ao.40.004526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We describe the experimental evaluation of a shearing interferometer concept for at-wavelength testing of extreme-ultraviolet optics. The concept is based on the Ronchi test, which has been modified by a new design for entrance and exit gratings to suppress disturbing higher-order interference patterns. The interferometer concept has been tested on an experimental setup, of which all relevant parameters have been scaled from extreme-ultraviolet to visible-light wavelengths. A Twyman-Green interferometer has been integrated into the setup for comparison with the improved Ronchi test. A systematic difference of 7-12 mlambda rms has been found between wave fronts measured with the improved Ronchi test and with the Twyman-Green interferometer. Possible error sources have been analyzed. The accuracy of the interferometer is estimated to be 10 mlambda rms.
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Klei TR, Rehbein S, Visser M, Langholff WK, Chapman MR, French DD, Hanson P. Re-evaluation of ivermectin efficacy against equine gastrointestinal parasites. Vet Parasitol 2001; 98:315-20. [PMID: 11423189 DOI: 10.1016/s0304-4017(01)00436-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg x kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly (P<0.05) fewer (>99.0% reduction) adult small strongyles (Coronocyclus spp including C. coronatus, C. labiatus, C. labratus; Cyathostomum spp including C. catinatum, C. pateratum; Cylicocyclus spp including C. ashworthi, C. elongatus, C. insigne, C. leptostomum, C. nassatus, C. radiatus; Cylicodontophorus bicoronatus; Cylicostephanus spp including C. asymetricus, C. bidentatus, C. calicatus, C. goldi, C. longibursatus, C. minutus; Gyalocephalus capitatus; Parapoteriostomum spp including P. euproctus, P. mettami; Petrovinema poculatum; Poteriostomum spp including P. imparidentatum, P. ratzii) and adult large strongyles (Strongylus edentatus, S. vulgaris; Triodontophorus spp including T. brevicauda, T. serratus; Craterostomum acuticaudatum) than the controls. Ivermectin was also highly effective (94% to >99%, P<0.05-0.01) against Gasterophilus intestinalis larvae, Habronema spp., Oxyuris equi, Parascaris equorum. The data from these two trials confirm that ivermectin paste administered to horses orally at 200mcg x kg(-1) continues to be highly effective for treatment and control of a broad range of small and large strongyle species as well as other species of gastrointestinal parasites.
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Goodpaster BH, Carlson CL, Visser M, Kelley DE, Scherzinger A, Harris TB, Stamm E, Newman AB. Attenuation of skeletal muscle and strength in the elderly: The Health ABC Study. J Appl Physiol (1985) 2001; 90:2157-65. [PMID: 11356778 DOI: 10.1152/jappl.2001.90.6.2157] [Citation(s) in RCA: 821] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although loss of muscle mass is considered a cause of diminished muscle strength with aging, little is known regarding whether composition of aging muscle affects strength. The skeletal muscle attenuation coefficient, as determined by computed tomography, is a noninvasive measure of muscle density, and lower values reflect increased muscle lipid content. This investigation examined the hypothesis that lower values for muscle attenuation are associated with lower voluntary isokinetic knee extensor strength at 60 degrees/s in 2,627 men and women aged 70-79 yr participating in baseline studies of the Health ABC Study, a longitudinal study of health, aging, and body composition. Strength was higher in men than in women (132.3 +/- 34.5 vs. 81.4 +/- 22.0 N x m, P < 0.01). Men had greater muscle attenuation values (37.3 +/- 6.5 vs. 34.7 +/- 7.0 Hounsfield units) and muscle cross-sectional area (CSA) at the midthigh than women (132.7 +/- 22.4 vs. 93.3 +/- 17.5 cm(2), P < 0.01 for both). The strength per muscle CSA (specific force) was also higher in men (1.00 +/- 0.21 vs. 0.88 +/- 0.21 N x m x cm(-2)). The attenuation coefficient was significantly lower for hamstrings than for quadriceps (28.7 +/- 8.7 vs. 41.1 +/- 6.9 Hounsfield units, P < 0.01). Midthigh muscle attenuation values were lowest (P < 0.01) in the eldest men and women and were negatively associated with total body fat (r = -0.53, P < 0.01). Higher muscle attenuation values were also associated with greater specific force production (r = 0.26, P < 0.01). Multivariate regression analysis revealed that the attenuation coefficient of muscle was independently associated with muscle strength after adjustment for muscle CSA and midthigh adipose tissue in men and women. These results demonstrate that the attenuation values of muscle on computed tomography in older persons can account for differences in muscle strength not attributed to muscle quantity.
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Visser M. [Roaming through methodology. XXXIV. Limitations of predictive models]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2001; 145:1109-12. [PMID: 11450603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Predictive models can be readily used within the populations in which they were developed but they often give a less than satisfactory performance when applied to another population. The main cause of this poorer performance is the fact that predictive models are often developed and evaluated within one single population. In a lot of cases, the model includes too many predictors (or a small population is used), which increases the chance of overfitting. Both external and internal validation techniques have been developed to evaluate predictive models. The most stringent test is an external validation: the application of the model to a new population. The usability of a predictive model can be evaluated using the receiver operating characteristic (ROC) curve.
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Charlton KE, Schloss I, Visser M, Lambert EV, Kolbe T, Levitt NS, Temple N. Waist circumference predicts clustering of cardiovascular risk factors in older South Africans. CARDIOVASCULAR JOURNAL OF SOUTH AFRICA : OFFICIAL JOURNAL FOR SOUTHERN AFRICA CARDIAC SOCIETY [AND] SOUTH AFRICAN SOCIETY OF CARDIAC PRACTITIONERS 2001; 12:142-50. [PMID: 11533736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE AND DESIGN A cross-sectional analytical study to determine the cardiovascular risk factor profile of older residents of fishing villages on the West Coast of South Africa, and to determine which anthropometric measures are associated with risk factors. SUBJECTS A convenient community-based sample of 152 subjects of mixed ancestry aged 55 years and over was recruited door-to-door using an address list of age-eligible subjects provided by the local public health care clinics. METHODS Cardiovascular relationships were investigated between (i) number of risk factors (hypertension, hypercholesterolaemia, diabetes) and body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference; and (ii) continuous cardiovascular risk factor variables and physical activity, smoking, dietary intake, and 24-hour urinary sodium and potassium concentrations. RESULTS The prevalence of hypertension ( > or =160/95 mmHg) was 74.3% (95% CI: 67.2 - 81.4%). Neither 24-hour urinary sodium nor potassium concentrations was associated with blood pressure (BP). Past, but not present, moderate-intensity physical activity, particularly that associated with occupation, was negatively associated with systolic BP (r = -0.24, P < 0.05). The prevalence of diabetes and hypercholesterolaemia (serum cholesterol > or = 6.5 mmol/l) was 24.6% (95% CI: 17.2 - 32%) and 40% (95% CI: 31.8 - 48.2%), respectively. The percentage of subjects with 0, 1, or 2 or more cardiovascular risk factors was 13.4%, 44.1% and 42.5%, respectively. Subjects with a waist circumference > or = 92 cm had a significantly higher number of cardiovascular risk factors than those with a waist circumference < 92 cm ( chi(2) = 9.29, P < 0.01), and this association remained significant even after controlling for age, sex and smoking (P < 0.05). Neither BMI tertiles according to sex, nor a BMI cut-point > or =30, was significantly associated with a clustering of risk factors. CONCLUSION In a sample of older South Africans of mixed ancestry at high risk of cardiovascular disease, waist circumference measuring > or = 92 cm predicts clustering of risks factors, independently of BMI. This simple, population-specific reference value may provide a useful screening tool to identify at-risk individuals for targeted prevention for coronary heart disease and associated metabolic disorders.
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Casellas JM, Visser M, Tomé G, Cohen H, Soutric J, Arenoso H. [Escherichia coli eradication from the blader urine by amoxicillin-sulbactam. Intrinsic activity of the inhibitor]. Enferm Infecc Microbiol Clin 2001; 19:206-10. [PMID: 11446908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
RATIONALE At urine concentrations obtained after the oral administration of amoxicillin-sulbactam (500/500 mg) this combination inhibits roughly 90% of Escherichia coli and Proteus mirabilis strains. AIMS To administer amoxicilin-sulbactam 875/125 mg and to determine: a) minimum inhibitory concentration (MIC) of sulbactam for E. coli and P. mirabilis; b) urine inhibitory titres power (UIT) against amoxicillin-resistant E. coli or P. mirabilis; c) urine concentrations of sulbactam; and to verify whether sulbactam 125 mg as single drug, attains a high enough UIT to support the intrinsic action of the inhibitor; and to compare the activity of amoxicillin-sulbactam and amoxicillin-clavulanate and that of sulbactam and clavulanate. METHODS Twelve healthy volunteers received a single oral dose of amoxicillin-sulbactam 875/125 mg or amoxicillin-clavulanate 875/125 mg, according to a randomized cross-over design. Urine samples were drawn at: 0 (basal), 2, 4, and 6 hours after dosing. Urine pH, specific gravidity and UIP were assessed. Thirty nine strains isolated from urine samples were used: 30 TEM-1 producing E. coli strains and 3 extended spectrum CTX-M-2 betalactamase-producing E. coli; and 6 P. mirabilis resistant to both combinations. In 6 healthy volunteers, sulbactam 125 mg was administered orally and UIT against E. coli (MIC amoxicillin > 2048 mg/l) was assessed. RESULTS AND DISCUSSION MIC-90 for amoxicillin plus sulbactam or clavulanate were similar to those for sulbactam or clavulanate alone, without any difference attributable to the chemical composition of the urine. The activity of amoxicillin plus the inhibitors could be due, not only to the inhibition of betalactamase but also to the intrinsic effect of the inhibitor. Both combinations showed an equivalent inhibitory activity. Two-hour UIT remained high for the entire 6-h evaluation period. Sulbactam concentration far exceed sulbactam MIC for the 6h-period, inhibiting urine E. coli. We disagree with the cut-off limit proposed for intermediate values of NCCLS, which, for these antimicrobial are 16/8, a value lower than those obtained in urine samples after the administration of betalactamase inhibitors. This may be an explanation for the beneficial effect of amoxicillin-sulbactam in the recovery of uncomplicated lower urinary tract infections in women when the involved strains were considered resistant by diffusional methods.
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Visser M, Rehbein S, Wiedemann C. Species of flea (siphonaptera) infesting pets and hedgehogs in Germany. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2001; 48:197-202. [PMID: 11393815 DOI: 10.1046/j.1439-0450.2001.00445.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The species of flea infesting pets and hedgehogs in Germany were investigated through a survey of small animal practitioners throughout the country who were asked to collect specimens at their veterinary practices. A total of 625 veterinarians/veterinary practices responded and provided 2445 intact anti identifiable flea specimens. These fleas originated from 294 dogs (795 fleas), 334 cats (1152 fleas), 76 hedgehogs (481 fleas), five domestic rabbits (10 fleas), one golden hamster (four fleas) and one ferret (three fleas). Dogs were found to be infested with Archaeopsylla erinacei, Chaetopsylla globiceps, Ctenocephalides canis, Ctenocephalides felis, Hystrichopsylla talpae, Nosopsyllus fasciatus, Paraceras melis and Pulex irritans. From cats, Archaeopsylla erinacei, Ceratophyllus gallinae, Ceratophyllus garei, Ctenocephalides felis, Ctenophthalmus assimilis, Hystrichopsylla talpae, Monopsyllus sciurorum, Nosopsyllus fasciatus, Spilopsyllus cuniculi and Typhloceras poppei were collected. In both dogs and cats the most prevalent species were Ctenocephalides felis (78.9% and 91.6%, respectively) and Archaeopsylla erinacei (21.1% and 12.6%, respectively) followed by Ctenocephalides canis in dogs (5.8%) and Hystrichopsylla talpae in cats (1.2%). The fleas isolated from rabbits were Ctenocephalides felis, Hystrichopsylla talpae and Spilopsyllus cuniculi. Nosopsyllus fasciatus and Ctenocephalides felis were recovered from the golden hamster and the ferret, respectively. The hedgehogs were found to be infested with Archaeopsylla erinacei, Ceratophyllus gallinae and Ctenocephalides felis.
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Rehbein S, Lutz W, Visser M, Winter R. Beiträge zur Kenntnis der Parasitenfauna des Wildes in Nordrhein-Westfalen. 2. Der Endoparasitenbefall des Damwildes. ACTA ACUST UNITED AC 2001. [DOI: 10.1007/bf02242409] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hochberg D, Molina-París C, Visser M. Heat kernel regularization of the effective action for stochastic reaction-diffusion equations. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 63:036132. [PMID: 11308734 DOI: 10.1103/physreve.63.036132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2000] [Indexed: 05/23/2023]
Abstract
The presence of fluctuations and nonlinear interactions can lead to scale dependence in the parameters appearing in stochastic differential equations. Stochastic dynamics can be formulated in terms of functional integrals. In this paper we apply the heat kernel method to study the short distance renormalizability of a stochastic (polynomial) reaction-diffusion equation with real additive noise. We calculate the one-loop effective action and its ultraviolet scale dependent divergences. We show that for white noise a polynomial reaction-diffusion equation is one-loop finite in d=0 and d=1, and is one-loop renormalizable in d=2 and d=3 space dimensions. We obtain the one-loop renormalization group equations and find they run with scale only in d=2.
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Langlois JA, Mussolino ME, Visser M, Looker AC, Harris T, Madans J. Weight loss from maximum body weight among middle-aged and older white women and the risk of hip fracture: the NHANES I epidemiologic follow-up study. Osteoporos Int 2001; 12:763-8. [PMID: 11605743 DOI: 10.1007/s001980170053] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Although weight loss increases bone loss and hip fracture risk in older women, little is known about the relation between weight loss in middle-aged women and subsequent hip fracture risk. The objective of this study was to determine the association between weight loss from reported maximum body weight in middle-aged and older women and the risk of hip fracture. Data were from a nationally representative sample of 2180 community-dwelling white women aged 50-74 years from the Epidemiologic Follow-up Study of the first National Health and Nutrition Examination Survey (NHEFS). In this prospective cohort study, incident hip fracture was ascertained during 22 years of follow-up. The adjusted relative risks associated with weight loss of 10% or more from maximum body weight were elevated for both middle-aged (RR 2.54; 95% CI 1.10-5.86) and older women (RR 2.04; 95% CI 1.37-3.04). For both ages combined, women in the lowest tertile of body mass index at maximum who lost 10% or more of weight had the highest risk of hip fracture (RR 2.37; 95% CI 1.32-4.27). Weight loss from maximum reported body weight in women aged 50-64 years and 65-74 years increased their risk of hip fracture, especially among those who were relatively thin. Weight loss of 10% or more from maximum weight among both middle-aged and older women is an important indicator of hip fracture risk.
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Visser M, Wieringa P. PREHEP: human error probability based process unit selection. ACTA ACUST UNITED AC 2001. [DOI: 10.1109/5326.923264] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
OBJECTIVE Human adipose tissue expresses and releases the proinflammatory cytokine interleukin-6, potentially inducing low-grade systemic inflammation in persons with excess body fat. To limit potential confounding by inflammation-related diseases and subclinical cardiovascular disease, we tested the hypothesis that overweight is associated with low-grade systemic inflammation in children. DESIGN AND SETTING The third National Health and Nutrition Examination Survey, 1988-1994, a representative sample of the US population. PARTICIPANTS A total of 3512 children 8 to 16 years of age. OUTCOME MEASURES Elevated serum C-reactive protein concentration (CRP; >/=.22 mg/dL) and white blood cell count (10(9) cells/L). RESULTS Elevated CRP was present in 7.1% of the boys and 6.1% of the girls. Overweight children (defined as having a body mass index or a sum of 3 skinfolds (triceps, subscapula, and supra-iliac) above the gender-specific 85th percentile) were more likely to have elevated CRP than were their normal-weight counterparts. After adjustment for potential confounders, including smoking and health status, the odds ratio (OR) was 3.74 (95% confidence interval [CI]: 1.66-8.43) for overweight boys and the OR was 3.17 (95% CI: 1.60-6.28) for overweight girls, based on the body mass index. Based on the sum of 3 skinfolds, these ORs were 5.11 (95% CI: 2.36-11.06) and 2.89 (95% CI: 1.49-5.59) for boys and girls, respectively. Overweight was also associated with statistically significant higher white blood cell counts. The results were similar when restricted to healthy, nonsmoking, nonestrogen-using children. CONCLUSIONS In children 8 to 16 years of age, overweight is associated with higher CRP concentrations and higher white blood cell counts. These findings suggest a state of low-grade systemic inflammation in overweight children. inflammation, obesity, children.
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Visser M. Comment on "Relativistic effects of light in moving media with extremely low group velocity". PHYSICAL REVIEW LETTERS 2000; 85:5252. [PMID: 11102234 DOI: 10.1103/physrevlett.85.5252] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2000] [Indexed: 05/23/2023]
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Visser M, Harris TB, Fox KM, Hawkes W, Hebel JR, Yahiro JY, Michael R, Zimmerman SI, Magaziner J. Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery. J Gerontol A Biol Sci Med Sci 2000; 55:M434-40. [PMID: 10952365 DOI: 10.1093/gerona/55.8.m434] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hip fracture in elderly persons has a serious impact on long-term physical function. This study determines the change in muscle strength and muscle mass after a hip fracture, and the associations between these changes and mobility recovery. METHODS Ninety community-dwelling women aged 65 years and older who had recently experienced a fracture of the proximal femur were included in the study. At 2 to 10 days after hospital admission, the women's grip strength, ankle dorsiflexion strength, and regional muscle mass (by dual-energy x-ray absorptiometry) were measured, and the prefracture level of independence for five mobility function items was assessed. All measurements were repeated at 12 months. RESULTS At follow-up, only 17.8% of the women had returned to their prefracture level of mobility function for all five items. Mobility function recovery was not related to change in skeletal muscle mass of the nonfractured leg or the arms. However, women who lost grip strength (mean loss of -28.7%, SD = 16.9%), or who lost ankle strength of the nonfractured leg (mean loss of -21.5%, SD = 14.7%), had a worse mobility recovery compared with those who gained strength (p = .04 and p = .09, respectively). In addition, chronic disease (p = .03), days hospitalized (p = .04), and self-reported hip pain (p = .07) were independent predictors of decline in mobility function. CONCLUSIONS The results suggest that loss of muscle strength, but not loss of muscle mass, is an independent predictor of poorer mobility recovery 12 months after a hip fracture. When confirmed by other studies, these findings may have implications for rehabilitation strategies after a hip fracture.
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Gallagher D, Ruts E, Visser M, Heshka S, Baumgartner RN, Wang J, Pierson RN, Pi-Sunyer FX, Heymsfield SB. Weight stability masks sarcopenia in elderly men and women. Am J Physiol Endocrinol Metab 2000; 279:E366-75. [PMID: 10913037 DOI: 10.1152/ajpendo.2000.279.2.e366] [Citation(s) in RCA: 276] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Skeletal muscle loss or sarcopenia in aging has been suggested in cross-sectional studies but has not been shown in elderly subjects using appropriate measurement techniques combined with a longitudinal study design. Longitudinal skeletal muscle mass changes after age 60 yr were investigated in independently living, healthy men (n = 24) and women (n = 54; mean age 73 yr) with a mean +/- SD follow-up time of 4.7 +/- 2.3 yr. Measurements included regional skeletal muscle mass, four additional lean components (fat-free body mass, body cell mass, total body water, and bone mineral), and total body fat. Total appendicular skeletal muscle (TSM) mass decreased in men (-0.8 +/- 1.2 kg, P = 0.002), consisting of leg skeletal muscle (LSM) loss (-0.7 +/- 0.8 kg, P = 0.001) and a trend toward loss of arm skeletal muscle (ASM; -0.2 +/- 0.4 kg, P = 0.06). In women, TSM mass decreased (-0.4 +/- 1.2 kg, P = 0.006) and consisted of LSM loss (-0.3 +/- 0.8 kg, P = 0.005) and a tendency for a loss of ASM (-0.1 +/- 0.6 kg, P = 0.20). Multiple regression modeling indicates greater rates of LSM loss in men. Body weight in men at follow-up did not change significantly (-0.5 +/- 3.0 kg, P = 0.44) and fat mass increased (+1.2 +/- 2.4 kg, P = 0.03). Body weight and fat mass in women were nonsignificantly reduced (-0.8 +/- 3.9 kg, P = 0.15 and -0.8 +/- 3.5 kg, P = 0.12). These observations suggest that sarcopenia is a progressive process, particularly in elderly men, and occurs even in healthy independently living older adults who may not manifest weight loss.
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Rehbein S, Barth D, Visser M, Winter R, Cramer LG, Langholff WK. Effects of psoroptes ovis infection and its control with an ivermectin controlled-release capsule on growing sheep. 1. Evaluation of weight gain, feed consumption and carcass value. Vet Parasitol 2000; 91:107-18. [PMID: 10889363 DOI: 10.1016/s0304-4017(00)00245-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg per day for 100 days. The lambs were infested with 50-60 P. ovis mites each on Days 14 and 21. Mites in skin scrapings were counted on Days 70, 84, 98, 112 and 126. Body weight and feed consumption were measured every 2 weeks from Day 0 to 126. The animals were slaughtered on Day 127 and their carcasses evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs treated on Day 0 had significantly (p<0.05) greater body weight gain from Day 0 to 84 (13.9 kg) and Day 0 to 126 (20.9 kg) than the untreated controls (9.6 and 12.8 kg, respectively) and the sheep treated on Day 84 (8.4 and 14.9 kg, respectively). Feed consumption (Days 0-126) for sheep treated with the IVM-CRC on Day 0 was higher than for sheep treated on Day 84 (p<0.05) and for the untreated controls (p<0.1). The carcasses of sheep treated with the IVM-CRC on Day 0 had significantly (p<0.05) higher warm and cold weights, carcass yield, rib eye area and back fat thickness than the untreated control group and the sheep treated with the IVM-CRC on Day 84. The sheep treated with the ivermectin CRC on either Day 0 or 84 had significantly (p<0.05) better muscle scores and lower muscle pH 1h post-slaughter than the untreated controls. There was no significant (p>0.1) difference between warm and cold carcass weights, carcass yield and rib eye area between sheep treated on Day 84 and untreated controls.
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Rehbein S, Oertel H, Barth D, Visser M, Winter R, Cramer LG, Langholff WK. Effects of Psoroptes ovis infection and its control with an ivermectin controlled-release capsule on growing sheep. 2. Evaluation of wool production and leather value. Vet Parasitol 2000; 91:119-28. [PMID: 10889364 DOI: 10.1016/s0304-4017(00)00244-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg/day for 100 days. The lambs were infested with 50-60 P. ovis mites each on days 14 and 21. The animals were shorn on Day 126. After slaughter on Day 127 the quality of the leather produced from their skins was evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs which were treated on Day 0 had significantly (p<0.05) greater clean fleece weight (1.5 kg) and fleece yield (52.1%) than the untreated controls (0.9 kg and 34.1%, respectively) or than lambs treated on Day 84 (1.0 kg and 47.8%, respectively). Clean fleece weight and fleece yield were in the tendency (p=0.055) or significantly (p<0. 001) greater, respectively, for lambs treated on Day 84 than for the untreated controls. The chrome tanned dried crust leather of all untreated controls and six of the 16 lambs treated on Day 84 showed grain surface defects such as discolourations, indurations and coarse, pitted grain. The useful (defect-free) leather size was significantly (p<0.01) higher for the lambs treated on Day 0 (100%) than for the lambs treated on Day 84 (82.7%) and the untreated controls (7.8%). The physical testing revealed that the leather of sheep treated on Day 0 had significantly (p<0.05) higher thickness, elongation break and tear resistance than the leather of both untreated controls and sheep treated on Day 84. There were no significant differences in the physical characteristics of the leather of the untreated controls and the sheep treated on Day 84.
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Salamone LM, Fuerst T, Visser M, Kern M, Lang T, Dockrell M, Cauley JA, Nevitt M, Tylavsky F, Lohman TG. Measurement of fat mass using DEXA: a validation study in elderly adults. J Appl Physiol (1985) 2000; 89:345-52. [PMID: 10904070 DOI: 10.1152/jappl.2000.89.1.345] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The accuracy of total body fat mass and leg fat mass measurements by fan-beam dual-energy X-ray absorptiometry (DEXA) was assessed in 60 healthy elderly subjects (aged 70-79 yr). Total fat and leg fat mass at four leg regions (total leg, thigh, midthigh, and calf) were measured with the QDR 4500A (Hologic, Waltham, MA). The four-compartment model and multislice computed tomography scans were selected as criterion methods for total fat and leg fat mass, respectively. Total fat mass from DEXA was positively associated with fat mass from the four-compartment model with a standard error of the estimate ranging from 1.4 to 1.6 kg. DEXA fan-beam tended to overestimate fat mass for total leg and total thigh fat mass, whereas only marginal differences in fat mass measurements at the midthigh and calf were demonstrated (</=0.08 kg, P < 0.0005). Although there were significant differences between DEXA fan beam and the criterion methods, these differences were of small magnitude, suggesting that DEXA is an accurate method for measurement of fat mass for the elderly.
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Chibale K, Visser M, Yardley V, Croft SL, Fairlamb AH. Synthesis and evaluation of 9,9-dimethylxanthene tricyclics against trypanothione reductase, Trypanosoma brucei, Trypanosoma cruzi and Leishmania donovani. Bioorg Med Chem Lett 2000; 10:1147-50. [PMID: 10866368 DOI: 10.1016/s0960-894x(00)00154-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Derivatives of 9,9-dimethylxanthene were synthesised and evaluated against trypanothione reductase (TR) and in vitro against parasitic trypanosomes and leishmania. High in vitro antiparasitic activity was observed for some derivatives with one compound showing high activity against all three parasites (ED50 values of 0.02, 0.48 and 0.32 microM, for Trypanosoma brucei, Trypanosoma cruzi, and Leishmania donovani, respectively). The lack of correlation between inhibitory activity against TR and ED50 values suggests that TR is not the target.
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Visser M, Newman AB, Nevitt MC, Kritchevsky SB, Stamm EB, Goodpaster BH, Harris TB. Reexamining the sarcopenia hypothesis. Muscle mass versus muscle strength. Health, Aging, and Body Composition Study Research Group. Ann N Y Acad Sci 2000; 904:456-61. [PMID: 10865789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The association of muscle mass and muscle strength with lower-extremity performance, as measured by timed repeated chair stands, was investigated using preliminary data from 3,075 Black and White participants (70-79 years old) in the Health, Aging, and Body Composition Study. Leg muscle mass (LM) was measured by dual-energy X-ray absorptiometry (Hologic QDR 4500). The maximal isokinetic torque of the leg extensors (LS) was measured at 60 degrees/s using a Kin-Com isokinetic dynamometer. Men were stronger, had greater LM, and better performance than women. As expected, low LS was associated with poorer performance after adjusting for race, study site, and body fat. Low LM was associated with poorer performance in men and women, with a potential threshold effect in women only. When LS and LM were modeled simultaneously, only LS remained independently associated with performance. In conclusion, muscle strength, but not muscle mass, is independently associated with lower-extremity performance.
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Harris TB, Visser M, Everhart J, Cauley J, Tylavsky F, Fuerst T, Zamboni M, Taaffe D, Resnick HE, Scherzinger A, Nevitt M. Waist circumference and sagittal diameter reflect total body fat better than visceral fat in older men and women. The Health, Aging and Body Composition Study. Ann N Y Acad Sci 2000; 904:462-73. [PMID: 10865790 DOI: 10.1111/j.1749-6632.2000.tb06501.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The validity of waist circumference and sagittal diameter as surrogate measures of visceral fat were assessed using preliminary cross-sectional data from the Health, Aging and Body Composition Study, a cohort of 3,075 men and women aged 70-79. Weight, body mass index, waist circumference, waist/thigh ratio, and sagittal diameter were compared by correlation, graphical analysis, and regression to total body fat as measured by dual-energy X-ray absorptiometry (Hologic 4500A), and to visceral fat area as measured by computerized tomography. We included 2,830 persons, 1,439 women and 1,391 men with complete data on all measurements. For both men and women, all measurements were strongly correlated with both total body fat and visceral fat except the waist/thigh ratio. However, waist circumference, sagittal diameter, weight, and body mass index were more closely related to total body fat than to visceral fat area (R2 for the linear regression of waist circumference on total body fat was 0.69 in women and men; R2 for linear regression of waist circumference on visceral fat area was 0.40 in women, and 0.49 in men). These data suggest that the contribution of visceral fat to health risks will be better assessed by directly measuring this fat depot.
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Visser M, Deeg DJ, Lips P, Harris TB, Bouter LM. Skeletal muscle mass and muscle strength in relation to lower-extremity performance in older men and women. J Am Geriatr Soc 2000; 48:381-6. [PMID: 10798463 DOI: 10.1111/j.1532-5415.2000.tb04694.x] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Low muscle strength is associated with poorer physical function, but limited empirical evidence is available to prove the relationship between muscle mass and physical function. We tested the hypothesis that persons with lower muscle mass or muscle strength have poorer lower-extremity performance (LEP). DESIGN A cross-sectional, population-based study. PARTICIPANTS A cohort of 449 men and women aged 65 years and older living in Amsterdam and its surroundings participating in the second examination (1995-1996) of the Longitudinal Aging Study Amsterdam. MEASUREMENTS Leg skeletal muscle mass was measured using dual-energy X-ray absorptiometry (DXA). Grip strength was used as an indicator of muscle strength. Timed functional performance tests, including walking and repeated chair stands, were used to assess LEP. RESULTS After adjustment for body height and age, leg muscle mass was positively associated with LEP in men (regression coefficient 0.178 [95% confidence interval 0.013-0.343], P = .035). In women an inverse association was observed, which became positive after additional adjustment for body mass index (BMI) (0.202 [-0.001-0.405], P = .052). Grip strength was positively associated with LEP in men and women. After additional adjustment for behavioral, physiological, and psychological variables, the associations between leg muscle mass and LEP disappeared, whereas grip strength remained to be independently associated with LEP in men (0.079 [0.042-0.116], P = .0001), with a tendency in women (0.046 [-0.009-0.101], P = .11). Results were similar when quartiles of leg muscle mass or grip strength were used. CONCLUSIONS These results suggest that low muscle strength, but not low muscle mass, is associated with poor physical function in older men and women. However, prospective studies are needed to investigate the association between loss of muscle mass and physical function.
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Rehbein S, Barth D, Visser M, Winter R, Langholff WK. Efficacy of an ivermectin controlled-release capsule against some rarer nematode parasites of sheep. Vet Parasitol 2000; 88:293-8. [PMID: 10714467 DOI: 10.1016/s0304-4017(99)00220-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A controlled trial was conducted to evaluate the efficacy of the intraruminal ivermectin controlled-release capsule (CRC) (IVOMEC Maximizer CR Capsule for Sheep, Merial Ltd.) against induced incoming third-stage larvae and established adult infections with some rarer gastrointestinal nematode parasites of sheep. Twenty-one worm-free lambs were allocated by restricted randomisation based on body weight within sex to one of the following treatments: unmedicated control, ivermectin CRC given on Day 0 prior to induced infection, and ivermectin CRC given on Day 70 after establishment of induced infection. The ivermectin CRC delivers ivermectin at a minimum dose rate of 20 microg/kg/day for 100 days. Infections were induced by daily administration of third-stage larvae for five consecutive days. Nematodes were counted on Day 84, 14 days after treatment of established infection. The treatment with the ivermectin CRC prevented the establishment of Ostertagia leptospicularis, O. ostertagi, Bunostomum trigonocephalum, Cooperia oncophora, C. punctata, C. surnabada, Nematodirus helvetianus, N. roscidus and Strongyloides papillosus by >99% as compared with the untreated controls (p < 0.01). The administration of the ivermectin CRC reduced established adult infections of O. ostertagi, B. trigonocephalum, C. oncophora, C. punctata, C. surnabada, N. roscidus and S. papillosus by >99% (p < 0.01), and reduced established adult infections of O. leptospicularis and N. helvetianus by 96.5 and 98.4% (p < 0.01), respectively.
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Rantanen T, Harris T, Leveille SG, Visser M, Foley D, Masaki K, Guralnik JM. Muscle strength and body mass index as long-term predictors of mortality in initially healthy men. J Gerontol A Biol Sci Med Sci 2000; 55:M168-73. [PMID: 10795731 DOI: 10.1093/gerona/55.3.m168] [Citation(s) in RCA: 406] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Muscle weakness, low body weight, and chronic diseases are often observed in the same people; however, the association of muscle strength with mortality, independent of disease status and body weight, has not been elucidated. The aim was to assess hand grip strength as a predictor of all-cause mortality within different levels of body mass index (BMI) in initially disease-free men. METHODS Mortality was followed prospectively over 30 years. Maximal hand grip strength tests and BMI assessments were done at baseline in 1965 to 1970. The participants were 6040 healthy men aged 45 to 68 years at baseline living on Oahu, Hawaii. RESULTS The death rates per 1000 person years were 24.6 in those with BMI <20, 18.5 in the middle BMI category, and 18.0 in those with BMI > or = 25. For grip strength tertiles, the mortality rates were 24.8 in the lowest, 18.5 in the middle, and 14.0 in the highest third. In Cox regression models, within each tertile of grip strength, BMI showed only minimal effect on mortality. In contrast, in each category of BMI there was a gradient of decreasing mortality risk with increasing grip strength. Among those with BMI <20, the adjusted relative risks (RRs) of mortality over 30 years were 1.36 (95% confidence interval 1.14-1.63) for those in the lowest third of strength at baseline, 1.27 (1.02-1.58) in the middle, and 0.92 (0.66-1.29) in the highest third. Correspondingly, for those with BMI 20-24.99, the RRs of death were 1.25 (1.08-1.45), 1.14 (1.00-1.32), and 1.0 (reference) in the lowest, middle, and highest third of grip strength, respectively. In those with BMI > or =25, the RRs were 1.39 (1.16-1.65) in the lowest, 1.27 (1.08-1.49) in the middle, and 1.14 (0.98-1.32) in the highest third of grip strength. Models were adjusted for age, education, occupation, smoking, physical activity, and body height. CONCLUSIONS In healthy middle-aged men, long-term mortality risk was associated with grip strength at baseline, independent of BMI. The possible interpretation of the finding is that early life influences on muscle strength may have long-term implications for mortality. Additionally, higher strength itself may provide greater physiologic and functional reserve that protects against mortality.
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Abstract
CONTEXT Human adipose tissue expresses and releases the proinflammatory cytokine interleukin 6, potentially inducing low-grade systemic inflammation in persons with excess body fat. OBJECTIVE To test whether overweight and obesity are associated with low-grade systemic inflammation as measured by serum C-reactive protein (CRP) level. DESIGN AND SETTING The Third National Health and Nutrition Examination Survey, representative of the US population from 1988 to 1994. PARTICIPANTS A total of 16616 men and nonpregnant women aged 17 years or older. MAIN OUTCOME MEASURES Elevated CRP level of 0.22 mg/dL or more and a more stringent clinically raised CRP level of more than 1.00 mg/dL. RESULTS Elevated CRP levels and clinically raised CRP levels were present in 27.6% and 6.7% of the population, respectively. Both overweight (body mass index [BMI], 25-29.9 kg/m2) and obese (BMI, > or =30 kg/m2) persons were more likely to have elevated CRP levels than their normal-weight counterparts (BMI, <25 kg/m2). After adjustment for potential confounders, including smoking and health status, the odds ratio (OR) for elevated CRP was 2.13 (95% confidence interval [CI], 1.56-2.91) for obese men and 6.21 (95% CI, 4.94-7.81) for obese women. In addition, BMI was associated with clinically raised CRP levels in women, with an OR of 4.76 (95% CI, 3.42-6.61) for obese women. Waist-to-hip ratio was positively associated with both elevated and clinically raised CRP levels, independent of BMI. Restricting the analyses to young adults (aged 17-39 years) and excluding smokers, persons with inflammatory disease, cardiovascular disease, or diabetes mellitus and estrogen users did not change the main findings. CONCLUSION Higher BMI is associated with higher CRP concentrations, even among young adults aged 17 to 39 years. These findings suggest a state of low-grade systemic inflammation in overweight and obese persons.
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Hochberg D, Molina-París C, Pérez-Mercader J, Visser M. Effective action for stochastic partial differential equations. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:6343-60. [PMID: 11970549 DOI: 10.1103/physreve.60.6343] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/1999] [Indexed: 04/18/2023]
Abstract
Stochastic partial differential equations (SPDEs) are the basic tool for modeling systems where noise is important. SPDEs are used for models of turbulence, pattern formation, and the structural development of the universe itself. It is reasonably well known that certain SPDEs can be manipulated to be equivalent to (nonquantum) field theories that nevertheless exhibit deep and important relationships with quantum field theory. In this paper we systematically extend these ideas: We set up a functional integral formalism and demonstrate how to extract all the one-loop physics for an arbitrary SPDE subject to arbitrary Gaussian noise. It is extremely important to realize that Gaussian noise does not imply that the field variables undergo Gaussian fluctuations, and that these nonquantum field theories are fully interacting. The limitation to one loop is not as serious as might be supposed: Experience with quantum field theories (QFTs) has taught us that one-loop physics is often quite adequate to give a good description of the salient issues. The limitation to one loop does, however, offer marked technical advantages: Because at one loop almost any field theory can be rendered finite using zeta function technology, we can sidestep the complications inherent in the Martin-Siggia-Rose formalism (the SPDE analog of the Becchi-Rouet-Stora-Tyutin formalism used in QFT) and instead focus attention on a minimalist approach that uses only the physical fields (this "direct approach" is the SPDE analog of canonical quantization using physical fields). After setting up the general formalism for the characteristic functional (partition function), we show how to define the effective action to all loops, and then focus on the one-loop effective action and its specialization to constant fields: the effective potential. The physical interpretation of the effective action and effective potential for SPDEs is addressed and we show that key features carry over from QFT to the case of SPDEs. An important result is that the amplitude of the two-point function governing the noise acts as the loop-counting parameter and is the analog of Planck's constant in this SPDE context. We derive a general expression for the one-loop effective potential of an arbitrary SPDE subject to translation-invariant Gaussian noise, and compare this with the one-loop potential for QFT.
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Rehbein S, Visser M. Efficacy of an injectable ivermectin/clorsulon combination against Fasciola hepatica in sheep. Vet Rec 1999; 145:468. [PMID: 10576286 DOI: 10.1136/vr.145.16.468] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Visser M, Fuerst T, Lang T, Salamone L, Harris TB. Validity of fan-beam dual-energy X-ray absorptiometry for measuring fat-free mass and leg muscle mass. Health, Aging, and Body Composition Study--Dual-Energy X-ray Absorptiometry and Body Composition Working Group. J Appl Physiol (1985) 1999; 87:1513-20. [PMID: 10517786 DOI: 10.1152/jappl.1999.87.4.1513] [Citation(s) in RCA: 311] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of the study was to examine the accuracy of fan-beam dual-energy X-ray absorptiometry (DEXA) for measuring total body fat-free mass (FFM) and leg muscle mass (MM) in elderly persons. Participants were 60 men and women aged 70-79 yr and with a body mass index of 17.5-39.8 kg/m(2). FFM and MM at four leg regions were measured by using DEXA (Hologic 4500A, v8.21). A four-compartment body composition model (4C) and multislice computed tomography (CT) of the legs were used as the criterion methods for FFM and MM, respectively. FFM by DEXA was positively associated with FFM by 4C (R(2) = 0.98, SE of estimate = 1.6 kg). FFM by DEXA was higher [53.5 +/- 12.0 (SD) kg] than FFM by 4C (51.6 +/- 11.9 kg; P < 0.001). No association was observed between the difference and the mean of the two methods. MM by DEXA was positively associated with CT at all four leg regions (R(2) = 0.86-0.96). MM by DEXA was higher than by CT in three regions. The results of this study suggest that fan-beam DEXA offers considerable promise for the measurement of total body FFM and leg MM in elderly persons.
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Visser M, Launer LJ, Deurenberg P, Deeg DJ. Past and current smoking in relation to body fat distribution in older men and women. J Gerontol A Biol Sci Med Sci 1999; 54:M293-8. [PMID: 10411016 DOI: 10.1093/gerona/54.6.m293] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Smoking is reported to be positively related to abdominal fat in young and middle-aged persons; however, it is unclear whether this relationship exists in elderly persons. Behavioral influence on fat distribution is of importance because of the accumulation of abdominal fat with age and its associated health risks. METHODS The relationship was investigated in a population-based sample of 1,178 men and 1,163 women aged 55-85 years, representative of the Dutch older population in 1992-1993. Waist and hip circumference and their ratio were used as indices of fat distribution. Past and current smoking habits were obtained by questionnaire. RESULTS Smoking was associated with waist/hip-ratio (WHR) in men, with current smokers having the highest WHR and never smokers the lowest. A dose-response relationship between the daily number of cigarettes smoked and WHR was observed in men. These associations remained significant after adjustment for confounding due to age, education, body mass index, health status, alcohol intake, and sports activity. The dose-response relationship did not change after additional adjustment for duration of smoking. Among former male smokers, recent quitters had a higher WHR compared to long-term quitters. Additional analysis showed that smoking was more strongly associated with waist than with hip circumference. In women the relationship between smoking and fat distribution was not clear. CONCLUSIONS Past and current smoking habits are positively associated with abdominal fat in older men, but not in older women.
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Frank L, Marian A, Visser M, Weinberg E, Potter PC. Exposure to peanuts in utero and in infancy and the development of sensitization to peanut allergens in young children. Pediatr Allergy Immunol 1999; 10:27-32. [PMID: 10410914 DOI: 10.1034/j.1399-3038.1999.101010.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study attempted to determine the underlying factors that may influence the development of peanut sensitization in young children in South Africa. One of our objectives was to ascertain whether the consumption of peanuts or peanut-containing foods during pregnancy and lactation by mothers from atopic families impacted upon the development of an allergic response to peanuts in the child. Forty-three children between the ages of 0 and 3 yr participated in this study. There were 25 peanut-sensitized subjects and 18 control subjects (children sensitized to milk and/or egg, but not to peanuts). A significant association was found between peanut sensitization and sensitivity to soya (p=0.0002), wheat (p=0.03), and cod fish. We found that mothers who consumed peanuts more than once a week during pregnancy were more likely to have a peanut-allergic child than mothers who consumed peanuts less than once a week (odds ratio=3.97, 98% confidence interval 0.73-24). Peanuts or peanut butter was introduced into the child's diet from a significantly younger age in the peanut-allergic subjects (p<0.03). There was a positive correlation in the peanut-allergic subjects between age of introduction of peanuts and age at the onset of symptoms (r=0.63). Exclusive breast feeding did not protect against the development of peanut sensitization. Peanut allergy is associated with an increased risk of sensitization to other foods. It is more likely to occur if mothers eat peanuts more frequently during pregnancy and introduce it early to the infant's diet. These features highlight potentially avoidable factors that might prevent sensitization.
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Arjan JA, Visser M, Zeyl CW, Gerrish PJ, Blanchard JL, Lenski RE. Diminishing returns from mutation supply rate in asexual populations. Science 1999; 283:404-6. [PMID: 9888858 DOI: 10.1126/science.283.5400.404] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Mutator genotypes with increased mutation rates may be especially important in microbial evolution if genetic adaptation is generally limited by the supply of mutations. In experimental populations of the bacterium Escherichia coli, the rate of evolutionary adaptation was proportional to the mutation supply rate only in particular circumstances of small or initially well-adapted populations. These experiments also demonstrate a "speed limit" on adaptive evolution in asexual populations, one that is independent of the mutation supply rate.
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Langlois JA, Rosen CJ, Visser M, Hannan MT, Harris T, Wilson PW, Kiel DP. Association between insulin-like growth factor I and bone mineral density in older women and men: the Framingham Heart Study. J Clin Endocrinol Metab 1998; 83:4257-62. [PMID: 9851760 DOI: 10.1210/jcem.83.12.5308] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Few studies of the GH axis and bone have focused specifically on elderly people. The objective of this study was to determine the association between insulin-like growth factor I (IGF-I) and bone mineral density (BMD) in 425 women and 257 men aged 72-94 who participated in the Framingham Osteoporosis Study component of the Framingham Heart Study in 1992-1993. Serum IGF-I level was determined by RIA. BMD at three femoral sites and the lumbar spine was determined by dual x-ray absorptiometry, and at the radius by single-photon absorptiometry. IGF-I level was positively associated with BMD at all five sites (Ward's area, femoral neck, trochanter, radius, and lumbar spine) in women after adjustment for weight loss and other factors (P < or = 0.01) and protein intake in a subset of participants (0.006 < P < 0.07). A threshold effect of higher BMD was evident at each of the 3 femoral sites and the spine (P < 0.03) but not at the radius for women in the highest quintile of IGF-I (> or = 179 g/liter) vs. those in the lowest four quintiles. IGF-I was not significantly associated with BMD in men. These results indicate that higher IGF-I levels are associated with greater BMD in very old women, and suggest that future clinical trials employing GH may have a role in the development of treatments for older women with osteoporosis.
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Rehbein S, Visser M, Winter R. [Helminth species of goats in Germany]. BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT 1998; 111:427-31. [PMID: 9880938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The helminth fauna of the gastrointestinal tract of 25 and the respiratory organs and the livers of 6 German goats was qualitatively and quantitatively examined. One trematode species (Dicrocoelium dendriticum), 2 species of cestodes (Moniezia expansa and metacestodes of Taenia hydatigena) and 28 species of nematodes (24 in the gastrointestinal tract and 4 in the lungs) were recorded. Two goats were infested with Oestrus ovis larvae. The most prevalent species were Ostertagia circumcincta and Chabertia ovina (84% each), Ostertagia trifurcata and Oesophagostomum venulosum (76% each), Ostertagia pinnata and Trichostrongylus colubriformis (64% each), Trichuris ovis (60%) and Skrjabinema ovis and Trichuris globulosa (56% each). The highest mean worm counts were seen in goats infected with Skjabinema ovis (4003), Ostertagia circumcincta (2501), Trichostrongylus axei (1825), Trichostrongylus colubriformis (1578) and Nematodirus battus (1050). Totally, the goats did harbour more nematodes in the abomasum (3734) than in the small intestine (1707) or the large intestine (2343). The lungs were parasitized by Cystocaulus ocreatus, Muellerius capillaris, Neostrongylus linearis and Protostrongylus rufescens.
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Rehbein S, Visser M, Winter R. [Endoparasitic infections in sheep from the Swabian Alb]. DTW. DEUTSCHE TIERARZTLICHE WOCHENSCHRIFT 1998; 105:419-24. [PMID: 9857565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The endoparasite fauna of 59 slaughtered sheep (30 lambs, 29 ewes) from the Swabian Alb, Germany, was examined. One species of trematodes, 3 species of cestodes, 29 species of nematodes (23 species of gastro-intestinal and 6 species of lung nematodes), 1 species of arthropodes and 1 species of protozoa were recorded. All animals were infected with Dicrocoelium dentriticum as well as gastro-intestinal and lung nematodes, 45.8% with Moniezia spp., 15.3% with Cysticercus tenuicollis, 55.9% with Oestrus ovis and 11.9% with Sarcocystis gigantea. The most important gastro-intestinal nematodes were Ostertagia circumcincta and Cooperia curticei, which were recorded in all sheep, Ostertagia trifurcata and Chabertia ovine (98.3% each), Oesophagostumum venulosum (96.6%), Nematodirus filicollis (81.4% each), Ostertagia pinnata (78.0%), Trichuris ovis and Trichostrongylus colubriformis (76.3% each). The ewes harboured more abomasal and small intestinal nematodes (1819 and 3702) than the lambs (695 and 1730), which haboured more large intestinal nematodes (177) than those (56). The most often recorded lungworms were Cystocaulus ocreatus (74.6%) and Muellerius capillaris (72.9%), followed by Neostrongylus linearis (57.6%), Dictyocaulus filaria (50.8%), Protostrongylus brevispiculum (37.3%) and Protostrongylus rufescens (28.8%). The ewes carried higher lungworm burdens than the lambs.
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Visser M, Langlois J, Guralnik JM, Cauley JA, Kronmal RA, Robbins J, Williamson JD, Harris TB. High body fatness, but not low fat-free mass, predicts disability in older men and women: the Cardiovascular Health Study. Am J Clin Nutr 1998; 68:584-90. [PMID: 9734734 DOI: 10.1093/ajcn/68.3.584] [Citation(s) in RCA: 247] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Using data from the Cardiovascular Health Study, we studied the relation between body composition (fat mass and fat-free mass, assessed by bioelectrical impedance) and self-reported, mobility-related disability (difficulty walking or stair climbing) in 2714 women and 2095 men aged 65-100 y. In a cross-sectional analysis at baseline (1989-1990), disability was reported by 26.5% of the women and 16.9% of the men. A positive association was observed between fat mass and disability. The odds ratio for disability in the highest quintile of fat mass was 3.04 (95% CI: 2.18, 4.25) for women and 2.77 (95% CI: 1.82, 4.23) for men compared with those in the lowest quintile. Low fat-free mass was not associated with a higher prevalence of disability. In a longitudinal analysis among persons not reporting disability at baseline, 20.3% of the women and 14.8% of the men reported disability 3 y later. Fat mass at baseline was predictive of disability 3 y later, with odds ratios of 2.83 (95% CI: 1.80, 4.46) for women and 1.72 (95% CI: 1.03, 2.85) for men in the highest quintile of fat. The increased risk was not explained by age, physical activity, chronic disease, or other potential confounders. Low fat-free mass was not predictive of disability. The results showed that high body fatness is an independent predictor of mobility-related disability in older men and women. These findings suggest that high body fatness in old age should be avoided to decrease the risk of disability.
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