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F de Vries

Publications and source records attributed to F de Vries.

13 recordsLinked to original sources
PubMed2006

Associations between prion protein genotype and type traits in East Friesian milk sheep.

Linear models were used to analyse the relationships between the prion protein genotypes and the height at the withers and rump, the heart girth and the length of the trunk of 440 East Friesian milk sheep. Significant associations were found between the ARR allele and the height of the withers and rump, and heart girth. The average height at the withers of the homozygous ARR/ARR sheep was 1.9 cm less than that of ARQ/ARQ sheep and 1.6 cm less than in sheep heterozygous for ARR; the height at the rump, length of the trunk and heart girth were similarly smaller. In the ARR/ARR ewes, the average height at the withers was 2.6 cm less and the height at the rump was 1.9 cm less than in the ARQ/ARQ ewes.

Alleles↗
PubMed2006

Insulin-like growth factor type-1 receptor down-regulation associated with dwarfism in Holstein calves.

Perturbations in endocrine functions can impact normal growth. Endocrine traits were studied in three dwarf calves exhibiting retarded but proportionate growth and four phenotypically normal half-siblings, sired by the same bull, and four unrelated control calves. Plasma 3,5,3'-triiodothyronine and thyroxine concentrations in dwarfs and half-siblings were in the physiological range and responded normally to injected thyroid-releasing hormone. Plasma glucagon concentrations were different (dwarfs, controls>half-siblings; P<0.05). Plasma growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin concentrations in the three groups during an 8-h period were similar, but integrated GH concentrations (areas under concentration curves) were different (dwarfs>controls, P<0.02; half-siblings>controls, P=0.08). Responses of GH to xylazine and to a GH-releasing-factor analogue were similar in dwarfs and half-siblings. Relative gene expression of IGF-1, IGF-2, GH receptor (GHR), insulin receptor, IGF-1 type-1 and -2 receptors (IGF-1R, IGF-2R), and IGF binding proteins were measured in liver and anconeus muscle. GHR mRNA levels were different in liver (dwarfs<controls, P<0.002; dwarfs<half-siblings, P=0.06; half-siblings<controls, P=0.08) but not in muscle. IGF-1R mRNA abundance in liver in half-siblings and controls was 2.4- and 2.5-fold higher (P=0.003 and P=0.001, respectively) and in muscle tissue was 2.3- and 1.8-fold higher (P=0.01 and P=0.08, respectively) than in dwarfs. Hepatic IGF-1R protein levels (Western blots) in muscle were 2.5-fold higher (P<0.05) and in liver and muscle (quantitative immunohistochemistry) were higher (P<0.02 and P<0.07, respectively) in half-siblings than in dwarfs. The reduced presence of IGF-1R may have been the underlying cause of dwarfism in studied calves.

Animals↗
PubMed2005

Severity of obstructive airway disease and risk of osteoporotic fracture.

The use of inhaled corticosteroids has been associated with a dose-related increased risk of fracture. This may be related to systemic absorption. However, several studies have found that patients with more severe reductions in pulmonary function had reduced bone mineral density, independent of inhaled corticosteroids. The objective of this study was to evaluate the relationship between disease severity and fracture risk. A large case-control study (108,754 cases) was conducted using data from the UK General Practice Research Database. It was found that higher doses of inhaled corticosteroids were associated with greater risks of fracture. The crude odds ratio of fracture among patients exposed to >1,600 microg beclomethasone equivalents per day was 1.95 (95% confidence interval (CI) 1.68-2.27). When adjustments were made for disease severity and use of bronchodilators, the initial dose-response relationship between inhaled corticosteroids and fracture risk disappeared (adjusted odds ratio of 1.19 (95% CI 1.01-1.41)). In conclusion, patients with severe obstructive airway disease are at risk of fracture. However, adequate adjustment for disease severity is essential when the association between the use of inhaled corticosteroids and risk of osteoporotic fracture is studied in observational research.

Administration, Inhalation↗
PubMed2004

[Immunophenotyping of haematologic malignancies].

Over the last 10 years, immunophenotyping of haematologic malignancies has become an indispensable diagnostic supplement to the classical morphological approach. Immunophenotyping of haematopoietic cells is performed with the use of a number of monoclonal antibodies (MOABs), which are directed specifically against structures of blood cells that become expressed at the different stages of differentiation and maturation. Cells to which the fluorescently labelled MOABs are directed can be recognised and measured using fluorescence microscopy or fluorescence flow cytometry. Many MOABs, fluorochromes and user-friendly flow cytometers have become available in the last 15 years, as a result of which immunophenotyping is now routinely applied in clinical practice. Immunophenotyping has the potential to classify leukaemias and other malignant lymphomas according to cell type and stage of maturation. This information is important for the establishment of the right diagnosis and prognosis, and for the optimal treatment choice. In a number of cases immunophenotyping provides information which cannot be obtained by simple morphological investigation. The immunophenotyping of blood and bone-marrow cells is also a sensitive method for detecting minimal residual disease after an apparent complete remission has been achieved.

Antibodies, Monoclonal↗
PubMed2004

Associations between the prion protein genotype and performance traits of meat breeds of sheep.

The prion protein (PrP) genotypes of four German meat breeds of sheep were examined in relation to their scores for muscle mass, conformation, wool quality, daily liveweight gain and ultrasonic measurements of the depth of back muscle and back fat. The dataset included 912 genotyped German texel sheep among 10,383 recorded sheep, 474 genotyped Suffolk sheep among 4079 recorded sheep, 271 genotyped German white-headed mutton sheep among 3393 recorded sheep, and 99 genotyped German black-headed mutton sheep among 1642 recorded sheep. The model included the fixed effects of PrP genotype, herd, year and season, test day, sex, rearing method, the regression coefficient of average age, and the random additive genetic effect of the animal. In all four breeds there were no statistically significant associations between these performance traits and the occurrence of ARR alleles and the ARR/ARR genotype except for the depth of back muscle and the daily liveweight gain of German black-headed mutton sheep; however, in this breed, the interpretation could be affected by the small number of animals involved. All the genotyped sheep had significantly better performance traits than the non-genotyped sheep.

Animals↗
PubMed2004

Breeding German sheep for resistance to scrapie.

Susceptibility to clinical scrapie is associated with polymorphisms in the prion protein (PrP) gene. The ARR allele reduces susceptibility to clinical disease caused by all known strains of the transmissible spongiform encephalopathy (TSE) agents. For the economically important German breeds of sheep the PrP allele frequencies are well known, but this paper presents representative genotyping results for 1526 sheep from two smaller milk sheep breeds and 2446 sheep from 14 mostly indigenous land sheep breeds. The ARR allele was detected in each breed but the breed-specific ARR frequencies varied between 1 and 63 per cent. In small populations with a very low ARR frequency the ARR allele could be lost by genetic drift. A simulation study was therefore made to examine the effects of different breeding schemes in populations of different sizes on attempts to select for the ARR allele in an endangered population. In breeds in which no homozygous rams are available the breeding strategy would depend on the number of heterozygous rams, and the genotyping and selection of suitable breeding ewes would reduce the time required to achieve a highly resistant population. In general, in all the breeds a selection programme to achieve 99 per cent ARR homozygous genotypes would be feasible in six to nine generations, depending on the initial allele frequencies. In small populations the inbreeding rate may increase if no specific mating plans are developed by the breeding organisations.

Alleles↗
PubMed2001

Use of statins and risk of fractures.

CONTEXT: Previous studies have reported lower fracture risks in patients taking 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins). OBJECTIVE: To investigate risk of fracture among statin users. DESIGN: Case-control study of data from the General Practice Research Database (GPRD). SETTING: A total of 683 general clinical practices in the United Kingdom. PATIENTS: Cases were 81 880 patients aged 50 years or older who had a fracture of the vertebrae, clavicle, humerus, radius/ulna, carpus, hip, ankle, or foot occurring between the enrollment date of their practice into the GPRD and July 1999, paired with 81 880 age-, sex-, and practice-matched controls. MAIN OUTCOME MEASURE: Risk of fracture in current users vs nonusers of statins. Odds ratios were estimated from conditional logistic regression and adjusted for smoking, medications and illnesses associated with fracture risk, and body mass index when known. RESULTS: The adjusted odds ratio (OR) for current use of statins compared with nonuse was 1.01 (95% confidence interval [CI], 0.88-1.16). For forearm, hip, and vertebral fractures, the ORs were 1.01 (95% CI, 0.80-1.27), 0.59 (95% CI, 0.31-1.13), and 1.15 (95% CI, 0.62-2.14), respectively. Relative to nonuse, a statin dosage of less than 20 mg/d (standardized to simvastatin) was associated with an adjusted OR of fracture of 1.13 (95% CI, 0.96-1.33); this OR was 1.07 (95% CI, 0.82-1.38) at dosages of 20 to 39.9 mg/d and 0.85 (95% CI, 0.47-1.53) at dosages of 40 mg/d or more. The adjusted OR was 0.71 (95% CI, 0.50-1.01) for statin use durations of 0 to 3 months, 1.31 (95% CI, 0.87-1.95) for durations of 3 to 6 months, 1.14 (95% CI, 0.82-1.58) for durations of 6 to 12 months, and 1.17 (95% CI, 0.99-1.40) for durations of more than 12 months. CONCLUSION: In this study, use of statins at dosages prescribed in clinical practice was not associated with a reduction in risk of fracture.

Aged↗
PubMed1993

Characterization of GmENOD40, a gene showing novel patterns of cell-specific expression during soybean nodule development.

In this paper, the soybean 'early nodulin' clone pGmENOD40 is characterized. The GmENOD40 encoded protein does not contain methionine and does not show homology to proteins identified so far. In situ hybridizations showed that this gene has a complex expression pattern during development of determinate soybean nodules. At early stages of development transcription is induced in dividing root cortical cells, the nodule primordium and the pericycle of the root vascular bundle. In mature soybean nodules, the gene is expressed in the uninfected cells of the central tissue and in the pericycle of the nodule vascular bundles. Studies on nodules devoid of intracellular bacteria and infection threads, showed that the expression of the gene in the nodule primordium is induced in these empty nodules, while the induction of the GmENOD40 gene in the nodule vascular bundle requires the presence of intracellular bacteria or infection threads. A pea cDNA clone homologous to GmENOD40 was isolated to enable in situ hybridization studies on indeterminate nodules. The expression patterns in both determinate and indeterminate nodules suggests that the ENOD40 protein might have a transport function.

Amino Acid Sequence↗
PubMed1984

Lymphocyte subpopulations in rheumatoid arthritis. An immunological, enzyme histochemical and morphological study.

Peripheral blood lymphocytes (PBL) and synovial fluid lymphocytes ( SFL ) of patients with rheumatoid arthritis (RA) were examined with monoclonal antibodies, with coated ox red blood cells for the expression of Fc receptors for IgG or IgM (T mu and T gamma cells), and incubated for the demonstration of alpha- naphtyl acetate esterase and acid phosphatase. Equal percentages of OKT4 and OKT8 PBL were found in clinically active and inactive RA patients, and in healthy controls, but decreased percentages of OKT4 and increased percentages of OKT8-positive lymphocytes were found among the SFL . The percentages of T mu and T gamma cells, the presence of HLA-DR membrane antigens on T lymphocytes as well as the staining pattern for the enzymes revealed that SFL of patients with RA were highly activated, compared to PBL of RA patients and healthy controls. It can be concluded from this study that a single determination of OKT4 and OKT8-positive lymphocytes in the peripheral blood of RA patients has no predictive value for disease activity. However, the results of the experiments on T lymphocyte-activation clearly showed preferential activation of SFL compared to PBL, indicating that activation of lymphocytes occurs at the site of inflammation.

Antibodies, Monoclonal↗
PubMedDate not supplied

Mapping the probability of exceeding critical thresholds for cadmium concentrations in soils in The Netherlands.

The probability of exceeding critical thresholds of Cd concentrations in the soil was mapped at a national scale. The critical thresholds in soil were based on food quality criteria for Cd in crops or in organs of cattle (Bos taurus), and were calculated by inverting a regression model for the Cd concentration in the crop, with the Cd concentration in soil, soil organic matter (SOM) content, clay content, and pH as predictors. The probability of exceeding the critical threshold for Cd in soil per node of a 500- x 500-m grid was approximated by Monte Carlo simulation, using the estimated cumulative distribution functions (cdf) of SOM, clay, pH, and Cd as input. The cdfs were estimated by simple indicator kriging with local prior means. For SOM, clay, and pH, detailed maps of soil type and land use were used to define subregions with assumed constant local means of the indicators (a priori distributions). The cdfs were sampled by Latin hypercube sampling. We accounted for correlation between the actual and critical Cd concentrations in soil by drawing Cd values from cdfs conditional on SOM and clay. The estimated probability for grassland is negligible, even in areas with high Cd concentrations in soil, and for maize (Zea mays L.) land the probability is almost everywhere smaller than 5%. For arable soils, however, these probabilities commonly are larger than 5% when sugar beet (Beta vulgaris L.) or wheat (Triticum aestivum L.) is taken as a reference crop, and locally exceed 50%.

Animals↗