172 resultados para FAT DISTRIBUTION
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Oolitic carbonates belonging to the Hauptrogenstein Formation of Bajocian (Middle Jurassic) age have been shown to be anomalously enriched in cadmium (Cd) throughout the Jura Mountains. Soils associated with this type of rock substratum may be naturally polluted with regards to Cd. At Schleifenberg (Canton Basel Land, Switzerland) the Hauptrogenstein Formation is almost entirely exposed along a trail on its SW flank. Cadmium concentrations were systematically measured throughout this formation and Cd enrichments in rocks are shown to occur to a maximum content of 4.9 mg kg(-1). We investigated associated soils, which cover the entire outcrop, and show that they have been formed through the weathering of the underlying bedrock and through the uptake of colluvial limestone fragments from the same and older formations. Cadmium contents in the soils reach a maximum value of 2.0 mg kg(-1), thereby exceeding the official Swiss indicative guideline value for soils fixed at 0.8 mg.kg(-1). Mineralogical analyses on the soils and associated bedrock suggest that no allochthonous component related to aeolian transport is present. Sequential extractions applied to selected soil samples show that about half of the Cd resides in the carbonate fraction coming from the fractured parent-rock, while the Cd released from the weathered carbonates is associated either with organic matter (over 10%) or with Fe and Mn-oxihydroxides (approximately 30%). No exchangeable Cd phase was found and this, together with the buffer capacity of this calcareous soil, suggests that the amount of mobile Cd is quite negligible in this soil, which also greatly reduces the amount of bioavailable
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Microtubule-associated proteins (MAPs) are essential components necessary for the early growth process of axons and dendrites, and for the structural organization within cells. Both MAP2 and MAP5 are involved in these events, MAP2 occupying a role predominantly in dendrites, and MAP5 being involved in both axonal and dendritic growth. In the chick dorsal root ganglia, pseudo-unipolar sensory neurons have a T-shaped axon and are devoid of any dendrites. Therefore, they offer an ideal model to study the differential expression of MAPs during DRG development, specifically during axonal growth. In this study we have analyzed the expression and localization of MAP2 and MAP5 isoforms during chick dorsal root ganglia development in vivo, and in cell culture. In DRG, both MAPs appeared as early as E5. MAP2 consists of the 3 isoforms MAP2a, b and c. On blots, no MAP2a could be found at any stage. MAP2b increased between E6 and E10 and thereafter diminished slowly in concentration, while MAP2c was found between stages E6 and E10 in DRG. By immunocytochemistry, MAP2 isoforms were mainly located in the neuronal perikarya and in the proximal portion of axons, but could not be localized to distal axonal segments, nor in sciatic nerve at any developmental stage. On blots, MAP5 was present in two isoforms, MAP5a and MAP5b. The concentration of MAP5a was highest at E6 and then decreased to a low level at E18. In contrast, MAP5b increased between E6 and E10, and rapidly decreased after E14. Only MAP5a was present in sciatic nerve up to E14. Immunocytochemistry revealed that MAP5 was localized mainly in axons, although neuronal perikarya exhibited a faint immunostaining. Strong staining of axons was observed between E10 and E14, at a time coincidental to a period of intense axonal outgrowth. After E14 immunolabeling of MAP5 decreased abruptly. In DRG culture, MAP2 was found exclusively in the neuronal perikarya and the most proximal neurite segment. In contrast, MAP5 was detected in the neuronal cell bodies and all along their neurites. In conclusion, MAP2 seems involved in the early establishment of the cytoarchitecture of cell bodies and the proximal axon segment of somatosensory neurons, while MAP5 is clearly related to axonal growth.
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Using autoradiographic techniques carried out under precise conditions we previously demonstrated that both sensory neurons and peripheral glial cells in dorsal root ganglia (DRG) or sciatic nerve, possess specific [125I]-labeled T3 binding sites. Thyroid hormone receptors (TR) include several isoforms (TR alpha(1), TR alpha(2), TR beta(1), TR beta(2...)) The present study demonstrates that while sensory neurons and peripheral glial cells both possess functional TR, they express a differential expression of TR isoforms. Using a panel of antisera to specific for the TR alpha-common (alpha(1) and alpha(2)), TR alpha-1 or TR beta-1 isoforms, we detected TRs isoform localization at the cellular level during DRG and sciatic nerve development and regeneration. Immunohistochemical analysis revealed that during embryonic life, sensory neurons express TR alpha-common and TR beta-1 rather than TR alpha-1. The number of TR alpha-common and TR beta-1 positive neurons as well as the intensity of labeling increased during the first two postnatal weeks and remained more or less stable in adult life. TR alpha-1 immunoreactivity, which was undetectable in embryonic sensory neurons, became discreetly visible in neurons after birth. In developing DRG and sciatic nerves, Schwann cells exhibited TR alpha-common and TR alpha-1 rather than TR beta-1 immunolabeling. The appearance of TR alpha-common and alpha-1 isoform immunoreactivity in the sciatic nerve was restricted to a short period ranging from E17 up to two postnatal weeks. By comparing TR alpha-common and TR alpha-1 immunostaining we can deduce that Schwann cells primarily express TR alpha-1. Afterwards, in adult rat sciatic nerve TR alpha isoforms was no more detected. However transection of sciatic nerve caused a reexpression of TR alpha isoforms in degenerating nerve. The prevalence of TR alpha in Schwann cells in vivo was correlated with in vitro results. The differential expression of TR alpha and beta by sensory neurons and Schwann cells indicates that the feedback regulation of circulating thyroid hormone could occur by binding to either the alpha or beta TR isoforms. Moreover, the presence of multiple receptor isoforms in developing sensory neurons suggests that thyroid hormone uses multiple signaling pathways to regulate DRG and sciatic nerve development.
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OBJECTIVE: To investigate the relationships between diet composition, body composition, and macronutrient oxidation at rest in obese and non-obese children. DESIGN: Cross-sectional study on fat intake, adiposity and postabsorptive macronutrients oxidation rates. SUBJECTS: 82 prepubertal (age: 9.1 +/- 1.1 y) children, 30 obese (FM = 32.6 +/- 6.1%) and 52 non-obese (FM = 15.6 +/- 5.1%). MEASUREMENTS: Subcutaneous skinfold thickness for body composition, diet history for energy and nutrient intake, indirect calorimetry for resting metabolic rate (RMR) and RQ measurement. RESULTS: Energy intake (EI) was comparable in obese and non-obese children. Adjusted for RMR by ANCOVA, using RMR as the covariate, EI was significantly lower in obese than in non-obese children indicating either a blunted physical activity or a systematic underestimation of EI. Protein and carbohydrate intakes expressed as a percentage of total energy intake (%EI) were not significantly different in the two groups. Lipid intake (%EI) was slightly but significantly higher in the obese than in the non-obese group either unadjusted or adjusted for RMR by ANCOVA. The postabsorptive RQ was significantly lower in obese than in non-obese children. In the total group, %FM was weakly but significantly correlated to lipid intake (%EI). CONCLUSION: Obese prepubertal children have a higher relative fat intake than non-obese children and their FM is associated with this factor. The lower postabsorptive RQ of obese children may indicate a compensatory mechanism to achieve fat equilibrium by enhanced fat oxidation.
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Little information exists regarding the effect of several obesity markers on blood pressure (BP) levels in youth. Transverse study including 2494 boys and 2589 girls. Height, weight and waist were measured according to the international criteria and body fat (BF) by bioimpedance. BP was measured by an automated device. Hypertension was defined using sex-specific, age-specific and height-specific observation-points. Body mass index (BMI) and waist were positively related with systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate in both sexes, whereas the relationships with BF were less consistent. Stepwise linear regression analysis showed that BMI was positively related with SBP and DBP in both sexes, whereas BF was negatively related with SBP in both sexes and with heart rate in boys only; finally, waist was positively related with SBP in boys and heart rate in girls. Age and heart rate-adjusted values of SBP and DBP increased with BMI: for SBP, 117+/-1, 123+/-1 and 124+/-1 mmHg in normal, overweight and obese boys, respectively; corresponding values for girls were 111+/-1, 114+/-1 and 116+/-2 mmHg (mean+/-SE, P<0.001). Overweight and obese boys had an odds ratio for being hypertensive of 2.26 (95% confidence interval: 1.79-2.86) and 3.36 (2.32-4.87), respectively; corresponding values for girls were 1.58 (confidence interval 1.25-1.99) and 2.31 (1.53-3.50). BMI, not BF or waist, is consistently and independently related to BP levels in children; overweight and obesity considerably increase the risk of hypertension.
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Rapport de synthèse : Introduction : La perfusion isolée du poumon à l'aide de Doxorubicine libre et une nouvelle forme de Doxorubicine liposomale pégylée (Liporubicine) est comparé en terme de pénétration et accumulation de Doxorubicine dans le tissu tumoral et pulmonaire dans un modèle de rats porteurs de tumeur sarcomateuse au niveau du poumon gauche. Matériel et méthode : Une tumeur sarcomateuse unique a été générée dans le poumon gauche de 39 Fischer rats, suivi 10 jours plus tard, par une perfusion isolée du poumon gauche (n =36) avec Doxorubicine libre (n=18) et Liporubicine (n=18) à une dose de 100 µg (n=9) et 400 µg (n=9) pour chaque formulation de Doxorubicine. Dans chaque poumon perfusé, la concentration de l'agent cytostatique et sa distribution ont été investiguées dans la tumeur et trois parties du poumon normal par HLPC (n=6) et par microscopie de florescence (n=3). Des analyses histologiques et inmunohistochimiques (facteur von Willebrand) ont été effectuées sur trois animaux non traités. Résultats : Les tumeurs sarcomateuses dans les animaux de contrôle démontraient une bonne vascularisation avec de fines branches capillaires qui étaient présentes partout dans les tumeurs. La perfusion isolée du poumon démontrait une distribution de l'agent cytostatique d'une manière hétérogène dans le poumon perfusé et une concentration de Doxorubicine inférieure dans les tumeurs par rapport au tissu pulmonaire sein pour les deux formulations de Doxorubicine et les deux doses appliquées. La perfusion isolée du poumon avec Doxorubicine libre démontrait une concentration significativement plus élevée que Liporubicine dans la tumeur et le parenchyme pulmonaire pour les deux doses appliquées (p < 0,01). Néanmoins, le coefficient de concentration tumorale et pulmonaire était plus bas pour Doxorubicine libre que pour Liporubicine pour une dose de 100 µg (0.27 ± 0.1 vs 0.53 ± 0.5, p=0.23) tandis qu'il était similaire pour les deux formulations de Doxorubicine à une dose de 400 µg (0.67 ± 0.2 vs 0.54 ± 0.2, p=0.34). Les deux formulations de Doxorubicine émergeaient un signal de fluorescence provenant de tous les compartiments du parenchyme pulmonaire mais seulement un signal sporadique et faible émergeant des tumeurs, provenant de la périphérie de la tumeur et des vaisseaux situés à l'intérieur de la tumeur, pour les deux doses appliquées. Conclusion : La perfusion isolée du poumon démontrait une distribution hétérogène de la Doxorubicine et sa forme liposomale dans le poumon perfusé et une accumulation plus faible dans la tumeur que dans le tissu parenchymateux adjacent pour les deux formulations de Doxorubicine et les deux doses appliquées.
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BACKGROUND AND AIMS: little is known regarding the reproducibility of body fat measuring devices; hence, we assessed the between and within-device reproducibility, and the within-day variability of body fat measurements. METHODS: body fat percentage was measured twice on seventeen female students aged between 18 and 20 with a body mass index of 21.9 ± 2.5 kg/m2 (mean ± SD) using seven bipolar bioelectrical impedance devices. Each participant was also measured each hour between 7:00 and 22:00. RESULTS: the correlation between first and second measurements was very high (Spearman r between 0.985 and 1.000, p<0.001), as well as between devices (Spearman r between 0.916 and 0.991, p<0.001). Repeated measurements analysis showed no differences were between devices (p=0.59) or readings (first vs. second: p=0.74). Conversely, significant differences were found between assessment periods throughout the day, measurements made in the morning being lower than those made in the afternoon (F test for repeated values= 6.58, p<0.001). CONCLUSIONS: the between and within-device reproducibility for measuring body fat is high, enabling the use of multiple devices in a single study. Conversely, small but significant changes in body fat measurements occur during the day, urging body fat measurements to be performed at fixed times.
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The in situ nuclear matrix was obtained from HeLa cells. After permeabilization with nonionic detergent, the resulting structures were incubated for 1 h at 37 degrees C to determine whether or not such an incubation might result in the redistribution of nuclear polypeptides which resisted extraction with buffers of high-ionic strength (1.6 M NaCl or 0.25 M (NH4)2SO4 as well as DNase I digestion. Using indirect immunofluorescence experiments and monoclonal antibodies we show that heating to 37 degrees C changes the distribution of a 160 kDa protein previously shown to be a component of the inner matrix network. On the other hand, a 125 kDa polypeptide was not affected at all by the incubation. Our results clearly indicate that the inclusion of a 37 degrees C incubation (for example during digestion with DNase I) in the protocol to obtain the in situ nuclear matrix can result in the formation of in vitro artifacts.
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Alternative morphotypes can confer important selective advantages in different habitats, whereas they can be penalized in other circumstances. In ectotherms, such as reptiles, the body colour can have direct effects on numerous aspects of their existence, such as thermoregulation or prey-predator interactions. Darker melanic individuals show lower skin reflectance and consequently heat up more rapidly and maintain optimal body temperatures more easily than lighter coloured individuals. As a consequence, melanistic individuals of diurnal species in cool areas may exhibit higher body condition, growth rate, survival and fecundity than lighter coloured individuals. Such advantages of dark coloration may be counterbalanced by a lower crypsis to predators and a decreased foraging efficiency. We investigated, in two montane populations of asp vipers Vipera aspis, the relationship between (1) colour polymorphism and body condition and length and (2) the coloration of individuals and their elevational distribution. We showed significant relationships between (1) the coloration, body condition and sex of individuals; (2) sexes and reproductive state and morph frequency; and (3) colour morphs that were distributed following an elevational gradient. Hence, colour polymorphism plays an important role in the ecology and evolution of the asp viper and is maintained through differential selective pressures.
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Peripheral nerve hyperexcitability (PNH) is one of the distal peripheral neuropathy phenotypes often present in patients affected by type 2 diabetes mellitus (T2DM). Through in vivo and ex vivo electrophysiological recordings in db/db mice, a model of T2DM, we observed that, in addition to reduced nerve conduction velocity, db/db mice also develop PNH. By using pharmacological inhibitors, we demonstrated that the PNH is mediated by the decreased activity of K(v)1-channels. In agreement with these data, we observed that the diabetic condition led to a reduced presence of the K(v)1.2-subunits in juxtaparanodal regions of peripheral nerves in db/db mice and in nerve biopsies from T2DM patients. Together, these observations indicate that the T2DM condition leads to potassium channel-mediated PNH, thus identifying them as a potential drug target to treat some of the DPN related symptoms.
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Background: As part of the second generation surveillance system for HIV/Aids in Switzerland, repeated cross-sectional surveys were conducted in 1993, 1994, 1996, 2000, 2006 and 2011 among attenders of all low threshold facilities (LTFs) with needle exchange programmes and/or supervised drug consumption rooms for injection or inhalation. The number of syringes distributed to the injectors has also been measured annually since 2000. Distribution in other settings, such as pharmacies, is also monitored nationally. Methods: Periodic surveys of LTFs have been conducted using an interviewer/self-administered questionnaire structured along four themes: socio-demographic characteristics, drug consumption, risk/preventive behaviour and health. Analysis is restricted to attenders who had injected drugs during their lifetime (IDU´s). Pearson's chi-square test and trend analysis were conducted on annual aggregated data. Trend significance was assessed using Stata's non parametric test nptrend. Results: Median age of IDU´s increased from 26 years in 1993 to 40 in 2011; most are men (78%). Total yearly number of syringes distributed by LTFs has decreased by 44% in 10 years. Use of cocaine has increased (Table 1). Injection, regular use of heroin and borrowing of syringes/needles have decreased, while sharing of other material remains stable. There are fewer new injectors; more IDU´s report substitution treatment. Most attenders had ever been tested for HIV (90% in 1993, 94% in 2011). Reported prevalence of HIV remained stable around 10%; that of HCV decreased from 62% in 2000 to 42% in 2011. Conclusions: Overall, findings indicate a decrease in injection as a means of drug consumption in that population. This interpretation is supported by data from other sources, such as a national decrease in distribution from other delivery points. Switzerland's behavioural surveillance system is sustainable and allows the HIV epidemic to be monitored among this hard-to-reach population, providing information for planning and evaluation.
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OBJECTIVES: Comparison of doxorubicin uptake, leakage and spatial regional blood flow, and drug distribution was made for antegrade, retrograde, combined antegrade and retrograde isolated lung perfusion, and pulmonary artery infusion by endovascular inflow occlusion (blood flow occlusion), as opposed to intravenous administration in a porcine model. METHODS: White pigs underwent single-pass lung perfusion with doxorubicin (320 mug/mL), labeled 99mTc-microspheres, and Indian ink. Visual assessment of the ink distribution and perfusion scintigraphy of the perfused lung was performed. 99mTc activity and doxorubicin levels were measured by gamma counting and high-performance liquid chromatography on 15 tissue samples from each perfused lung at predetermined localizations. RESULTS: Overall doxorubicin uptake in the perfused lung was significantly higher (P = .001) and the plasma concentration was significantly lower (P < .0001) after all isolated lung perfusion techniques, compared with intravenous administration, without differences between them. Pulmonary artery infusion (blood flow occlusion) showed an equally high doxorubicin uptake in the perfused lung but a higher systemic leakage than surgical isolated lung perfusion (P < .0001). The geometric coefficients of variation of the doxorubicin lung tissue levels were 175%, 279%, 226%, and 151% for antegrade, retrograde, combined antegrade and retrograde isolated lung perfusion, and pulmonary artery infusion by endovascular inflow occlusion (blood flow occlusion), respectively, compared with 51% for intravenous administration (P = .09). 99mTc activity measurements of the samples paralleled the doxorubicin level measurements, indicating a trend to a more heterogeneous spatial regional blood flow and drug distribution after isolated lung perfusion and blood flow occlusion compared with intravenous administration. CONCLUSIONS: Cytostatic lung perfusion results in a high overall doxorubicin uptake, which is, however, heterogeneously distributed within the perfused lung.
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Purpose: To report the magnetic resonance imaging (MRI) findings in athletic injuries of the extensor carpi ulnaris (ECU) subsheath, assessing the utility of gadolinium-enhanced (Gd) fat-saturated (FS) T1-weighted sequences with wrist pronation and supination. Methods and Materials: Sixteen patients (13 males, 3 females; mean age 30.3 years) with athletic injuries of the ECU subsheath sustained between January 2003 and June 2009 were included in this retrospective study. Initial and follow‑up 1.5-T wrist MRIs were performed with transverse T1-weighted and STIR sequences in pronation, and Gd FS T1-weighted sequences with wrist pronation and supination. Two radiologists assessed the type of injury (A to C), ECU tendon stability, associated lesions and rated pulse sequences using a three-point scale: 1 = poor, 2 = good and 3 = excellent. Results: Gd-enhanced FS T1-weighted transverse sequences in supination (2.63) and pronation (2.56) were most valuable, compared with STIR (2.19) and T1 weighted (1.94). Nine type A, one type B and six type C injuries were found. There were trends towards diminution in size, signal intensity and enhancement of associated pouches on follow‑up MRI and tendon stabilisation within the ulnar groove. Conclusion: Gd-enhanced FS T1-weighted sequences with wrist pronation and supination are most valuable in assessing and follow‑up athletic injuries of the ECU subsheath on 1.5-T MRI.