794 research outputs found
Sexually dimorphic tibia shape is linked to natural osteoarthritis in STR/Ort mice
Human osteoarthritis (OA) is detected only at late stages. Male STR/Ort mice develop knee OA spontaneously with known longitudinal trajectory, offering scope to identify OA predisposing factors. We exploit the lack of overt OA in female STR/Ort and in both sexes of parental, control CBA mice to explore whether early divergence in tibial bone mass or shape are linked to emergent OA
Research Notes : Zambia : Development of promiscuous soybean varieties
Zambia was perhaps the first country to initiate research on the development of promiscuous soybean varieties. Promiscuous soybean varieties have the capability of producing effective nodules with the indigenous rhizobia found in the Zambian soils. Two such varieties, \u27Magoye\u27 and \u27Hernon 147\u27, have already been released in Zambia
Excessive growth hormone expression in male GH transgenic mice adversely alters bone architecture and mechanical strength
Patients with acromegaly have a higher prevalence of vertebral fractures despite normal bone mineral density (BMD), suggesting that GH overexpression has adverse effects on skeletal architecture and strength. We used giant bovine GH (bGH) transgenic mice to analyze the effects of high serum GH levels on BMD, architecture, and mechanical strength. Five-month-old hemizygous male bGH mice were compared with age- and sex-matched nontransgenic littermates controls (NT; n=16/group). Bone architecture and BMD were analyzed in tibia and lumbar vertebrae using microcomputed tomography. Femora were tested to failure using three-point bending and bone cellular activity determined by bone histomorphometry. bGH transgenic mice displayed significant increases in body weight and bone lengths. bGH tibia showed decreases in trabecular bone volume fraction, thickness, and number compared with NT ones, whereas trabecular pattern factor and structure model index were significantly increased, indicating deterioration in bone structure. Although cortical tissue perimeter was increased in transgenic mice, cortical thickness was reduced. bGH mice showed similar trabecular BMD but reduced trabecular thickness in lumbar vertebra relative to controls. Cortical BMD and thickness were significantly reduced in bGH lumbar vertebra. Mechanical testing of femora confirmed that bGH femora have decreased intrinsic mechanical properties compared with NT ones. Bone turnover is increased in favor of bone resorption in bGH tibia and vertebra compared with controls, and serum PTH levels is also enhanced in bGH mice. These data collectively suggest that high serum GH levels negatively affect bone architecture and quality at multiple skeletal sites
Research Notes : Zambia : Summary of national soybean variety test (1982/83)
Results of the National Soybean Variety Trial are reported in Tables 1 and 2. Sixteen entries, comprising seven recommended varieties and nine new promising cultivars, were tested at seven different locations. Though the season started favorably, rains in December, 1982, were inade-quate in the southern half of the country for good stand establishment
Efficacy of Two Caries Detector Dyes in the Diagnosis of Dental Caries
Objective: The aim of the present study was to evaluate the efficacy of two caries detector dyes in the diagnosis of dental caries.Materials and Methods: Twenty extracted human posterior teeth without pulpal exposure were sectioned mesiodistally through the center of the lesions using a water-cooled disk.The tooth halves were randomly divided into two groups and treated with Caries Detector (CD) and Caries Check (CC) detector dyes. Access cavities were prepared followed by caries removal and dye application. All cavities were arbitrarily divided into two right and left sections and excavation of the stained areas was performed on the left parts, while the right sections remained untouched. Bacterial penetration into dentinal tubules was evaluated using Gram-stained decalcified sections under light microscopy. Sensitivity and specificity of both dyes were calculated.Results: The sensitivity of CD and CC were 74% and 71%,respectively. The specificity obtained for both dyes was 100%.Conclusion: Considering the low sensitivity of the dyes evaluated in the present study, it seems that they may not be reliable when used as the sole diagnostic technique for detection of carious lesions in posterior teeth
Investigation on replacement of fish oil by vegetable oils (rice bran, soybean and linseed) in diet of rainbow trout (Oncorhynchus mykiss)
The aim of the present study was to determine the impact of replacing the fish oil by alternative lipid sources in diets for rainbow trout (Oncorhynchus mykiss) on growth, fatty acid profiles of muscle. Five isonitrogenous and isoenergetic semipurified diets were formulated containing 100% rice bran oil (RBO), 100% linseed oil (LO), 100% Soybean oil (SO) and a 1:1:1:1 rice bran, linseed, soybean and fish oil mixture (MX) were compared to a pure fish oil (FO) diet. The diets were fed to apparent satiation twice a day to triplicate groups of 30 rainbow trout with an initial weight of 90g for 15 weeks at 12°C.At the end of the experiment, fillet samples were collected from fish for the measurement of fatty acid profile and fillet composition. Fish fed the FO diet had the highest weight gain over the experimental period (280.28 g), However no differences in growth rate and CF were observed across diet groups. Feed conversion ratios (FCR) ranged from 1.12 to 1.24. Significant difference in FCR was found in the group fed an FO diet. The fillet lipid concentrations and fatty acid composition of the fish were significantly affected by the experimental diets. Fish fed the FO diet contained significantly lower lipid levels (20.18%) than those fed the 4 other diets. The highest level of n-3 PUFA concentrations were recorded in fish fed the LO diet (21.8) with significant difference than other diets and the lowest were in those fed the RBO diet (7.84). Fish fed the SO diet contained significantly higher level of n-6 PUFA concentrations (31.72) than other diets and the lowest were in those fed the FO diet (19.15). Fish on the FO diet had a significantly greater percentage of DHA (10.10%) in muscle tissue compared with fish on all other diets and the lowest was in those fed the RBO diet (2.81%). However, the highest level of eicosapentaenoic acid (EPA) concentrations was recorded in fish fed the SO diet (1.84%) and the lowest in those fed the diet (0.67%). This study showed considerable reductions (about 3-fold) in the n-3/n-6 ratio when FO in the fish diet was replaced by rice bran and soybean oils, which may be extremely negative from a nutritional point of view. In other hand linseed oil had the highest n-3/n-6 ratio (0.91) that was comparable with fish oil n- 3/n-6 ratio (0.89). The results in this study imply that an appropriate mix of vegetable oils and FO can replace the sole use of FO in fish feeds
Impact of hepcidin antimicrobial peptide on iron overload in tuberculosis patients
Background: Iron acquisition is essential for the growth of Mycobacterium tuberculosis. Hepcidin is known as an antimicrobial peptide and a component of the innate immune response. Hepcidin inhibits M. tuberculosis growth in vitro. In this study, we decided to identify-582A> G variants of the HAMP promoter in patients with tuberculosis (TB) and investigate its effect on serum iron, ferritin, and hepcidin levels. Methods: The sample population consisted of 105 patients with TB and 104 healthy individuals. The-582A> G polymorphism was genotyped using a tetra-primers PCR set. Serum levels of hepcidin were determined using an ELISA kit. Statistical analysis was performed using SPSS software. Results: The G allele is meaningfully associated with TB disease (95% confidence interval = 2-4.8, p G polymorphism genotypes. There was significant reverse correlation between hepcidin and iron (r =-0.849, p = 0.006). Conclusion: A high association was found between serum hepcidin levels and the HAMP-582A> G variants in patients with TB. These observations indicate a hypothetical role of this polymorphism in iron metabolism. Hepcidin could perhaps be an option for the treatment of TB. © 2014 Informa Healthcare
Study on the growth parameters of Capoeta trutta (Heckel, 1843) in Shour River, Iran
In this study growth characteristics of 815 tuwini (Capoeta trutta) in Shour River were investigated during July 2010 through June 2011. The population was composed of 62.94% females and 32.02% males. Sex ratio was 1: 1.96, with significant differences observed at 1:1 (x^2= 150.6; df= 1; p<0.05). The age distribution of this population ranged from <1 to 6 years. The distribution of length and weight was between 95 and 300 mm. The average length, except in <1 year olds, was statistically significant between sexes and average weight in all age groups was statistically significant between sexes (p<0.05). Weight-length relationship was determined as W=0.0115L^2.9475 (R=0.91) in males and W=0.0096L^3.0025 (R= 0.88) in females. Von-Bertalanffy growth equation was Lt= 24.5(1-e^-0.333(t+2.54)) for males and Lt= 36.4 (1- e^-0.129(t+4.02)) for females. Growth performance index was also estimated as Φ=2.301 in males and Φ=2.223 in females
Sost haploinsufficiency provokes peracute lethal cardiac tamponade without rescuing the osteopenia in a mouse model of excess glucocorticoids
Glucocorticoid-induced secondary osteoporosis is the most predictable side-effect of this anti-inflammatory. One of the main mechanisms by which glucocorticoids achieve such deleterious outcome in bone is by antagonizing Wnt/β-catenin signalling. Sclerostin, encoded by Sost gene, is the main negative regulator of the pro-formative and anti-resorptive role of the Wnt signaling pathway in the skeleton. We hypothesized that the partial inactivation of sclerostin function by genetic manipulation will rescue the osteopenia induced by high endogenous glucocorticoid levels. Sost-deficient mice were crossed with an established mouse model of excess glucocorticoids and the effects on bone mass and structure were evaluated. Sost haploinsufficiency did not rescue the low bone mass induced by high glucocorticoids. Intriguingly, the critical manifestation of Sost-deficiency combined with glucocorticoid excess was sporadic, sudden, unprovoked, and non-convulsive death. Detailed histopathological analysis in a wide range of tissues identified peracute haemopericardium and cardiac tamponade to be the cause. These preclinical studies reveal outcomes with direct relevance to ongoing clinical trials exploring the use of anti-sclerostin antibodies as a treatment for osteoporosis. They particularly highlight a potential for increased cardiovascular risk and may inform improved stratification of patients that might otherwise benefit from anti-sclerostin antibody treatment
On the Energy Transfer Performance of Mechanical Nanoresonators Coupled with Electromagnetic Fields
We study the energy transfer performance in electrically and magnetically
coupled mechanical nanoresonators. Using the resonant scattering theory, we
show that magnetically coupled resonators can achieve the same energy transfer
performance as for their electrically coupled counterparts, or even outperform
them within the scale of interest. Magnetic and electric coupling are compared
in the Nanotube Radio, a realistic example of a nano-scale mechanical
resonator. The energy transfer performance is also discussed for a newly
proposed bio-nanoresonator composed of a magnetosomes coated with a net of
protein fibers.Comment: 9 Pages, 3 Figure
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