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71.
Chaventré A Delafosse J Rhaly AA Diarra JN Bellis G Roux F Kouamé P Pitté A Mayer G Gaimard M Dilumbu I 《Collegium antropologicum》1998,22(1):1-8
The iodine deficiency (ID), which affects 1 person out of 6, is relatively neglected by the responsible of Public Health Service, particularly in developing countries. Consequences of ID are far from being negligible: mental retardation, hypofertility, hyperplasia, carcinoma, early ageing and, in very exposed areas, endemic cretinism. Nevertheless, eradication is easy and cheap but it requires rigorous protocols and control of results. The elaboration of these protocols is complex because it must be adapted to environment, population and financial possibilities of concerned countries. Based on our experience in this field, we propose a combined protocol, between the Public Health too liberal approach and that of too expensive research, which can be adapted to several situations. 相似文献
72.
The organization of filamentous actin (F-actin) in living cells of the oomycete Phytophthora cinnamomi was determined during zoosporogenesis and zoospore encystment by microinjecting sporangia with fluorescently labeled phalloidin and observing resultant fluorescence by confocal microscopy. In multinucleate sporangia prior to the induction of cleavage, phalloidin labeling took the form of plaques which occurred mainly in the periphery of the sporangia. After induction of cleavage, phalloidin labeling showed that the plaques disappeared and that F-actin began to accumulate along the developing cleavage planes and around nuclei and water expulsion vacuoles. F-actin labeling was also observed near the plasma membrane in zoospores and young cysts but reverted to the plaque form in older cysts. Localization of F-actin close to the developing cleavage planes is consistent with the idea that actin microfilaments function in the positioning and expansion of the cleavage membranes. Observations of plaques of actin in living sporangia provide evidence that plaques are not aldehyde-induced fixation artifacts. Copyright 1998 Academic Press. 相似文献
73.
Serglycin is the major proteoglycan in most hematopoietic cells, including
monocytes and macrophages. The monoblastic cell line U937-1 was used to
study the expression of serglycin during proliferation and differentiation.
In unstimulated proliferating U937-1 cells serglycin mRNA is
nonconstitutively expressed. The level of serglycin mRNA was found to
correlate with the synthesis of chondroitin sulfate proteoglycan (CSPG).
The U937-1 cells were induced to differentiate into different types of
macrophage-like cells by exposing the cells to PMA, RA, or VitD3. These
inducers of differentiation affected the expression of serglycin mRNA in
three different ways. The initial upregulation seen in the normally
proliferating cells was not observed in PMA treated cells. In contrast, RA
increased the initial upregulation, giving a reproducible six times
increase in serglycin mRNA level from 4 to 24 h of incubation, compared to
a four times increase in the control cells. VitD3 had no effect on the
expression of serglycin mRNA. The incorporation of (35S)sulfate into CSPG
decreased approximately 50% in all three differentiated cell types.
Further, the (35S)CSPGs expressed were of larger size in PMA treated cells
than controls, but smaller after RA treatment. This was due to the
expression of CSPGs, with CS-chains of 25 and 5 kDa in PMA and RA treated
cells, respectively, compared to 11 kDa in the controls. VitD3 had no
significant effect on the size of CSPG produced. PMA treated cells secreted
75% of the (35S)PGs expressed, but the major portion was retained in cells
treated with VitD3 or RA. The differences seen in serglycin mRNA levels,
the macromolecular properties of serglycin and in the PG secretion
patterns, suggest that serglycin may have different functions in different
types of macrophages.
相似文献
74.
Luigi De Bellis Makoto Hayashi Pier Paolo Biagi Ikuko Hara-Nishimura Amedeo Alpi Mikio Nishimura 《Physiologia plantarum》1994,90(4):757-762
Aconitase (EC 4.2.1.3) was purified by column chromatography and SDS-PAGE. Specific antibodies for aconitase were prepared after affinity purification of the antiserum with purified aconitase. The antibodies reacted with purified pumpkin aconitase, and with the 98 kDa protein band after electrophoretic fractionation of extracts of pumpkin cotyledons. Immunoblot analysis revealed a protein with similar molecular mass in extracts of several plants. The intensity of the 98 kDa band increased as pumpkin cotyledons developed in darkness, and decreased thereafter upon illumination. Aconitase activity showed a similar pattern. Anion exchange chromatography of a homogenate of pumpkin cotyledons, followed by western blotting, displayed the presence of immunoreactive protein bands only in fractions showing aconitase activity. The results indicate that the antibodies were specific for aconitase. When we investigated the presence of immunoreactive bands after sucrose gradient fractionation, aconitase was detected in the supernatant fractions and in mitochondria, while a very low amount was found in glyoxysomes. These data provide additional proof that aconitase is not localized in glyoxysomes. 相似文献
75.
Discrimination between alpha-satellite DNA sequences from chromosomes 21 and 13 by using polymerase chain reaction. 总被引:2,自引:0,他引:2
alpha-Satellite subfamilies from chromosomes 21 and 13 are almost identical in sequence and cannot be distinguished from each other by hybridization techniques. A general method based on membrane-bound PCR is described here, allowing the discrimination of alpha-satellite DNA sequences from each of these two chromosomes, after detection by Southern blot hybridization. The PCR conditions were developed using somatic hybrid DNAs. The method was tested in membrane-bound PCR by using the alpha-satellite bands from a Southern blot of a CEPH family. The chromosomal origin of these bands, previously determined by linkage analysis, was confirmed by this method. 相似文献
76.
A novel pumpkin (Cucurbita pepo) short-chain acyl-coenzyme A (CoA) oxidase (ACOX) was purified to homogeneity by hydrophobic-interaction, hydroxyapatite, affinity, and anion-exchange chromatography. The purified enzyme is a tetrameric protein, consisting of apparently identical 47-kD subunits. The protein structure of this oxidase differs from other plant and mammalian ACOXs, but is similar to the protein structure of mammalian mitochondrial acyl-CoA dehydrogenase (ACDH) and the recently identified plant mitochondrial ACDH. Subcellular organelle separation by sucrose density gradient centrifugation revealed that the enzyme is localized in glyoxysomes, whereas no immunoreactive bands of similar molecular weight were detected in mitochondrial fractions. The enzyme selectively catalyzes the oxidation of CoA esters of fatty acids with 4 to 10 carbon atoms, and exhibits the highest activity on C-6 fatty acids. Apparently, the enzyme has no activity on CoA esters of branched-chain or dicarboxylic fatty acids. The enzyme is slightly inhibited by high concentrations of substrate and it is not inhibited by Triton X-100 at concentrations up to 0.5% (v/v). The characteristics of this novel ACOX enzyme are discussed in relation to other ACOXs and ACDHs. 相似文献
77.
Clunes MT Lindsay SL Roussa E Quinton PM Bovell DL 《Journal of molecular histology》2004,35(4):339-345
The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption. 相似文献
78.
79.
Domenico Cozzolino Anna Grandone Antonio Cittadini Giuseppe Palmiero Giovanni Esposito Annamaria De Bellis Raffaello Furlan Silverio Perrotta Laura Perrone Daniele Torella Emanuele Miraglia del Giudice 《PloS one》2015,10(4)
Background
The prevalence of obesity is increasing among children/adolescents. Subtle cardiovascular abnormalities, responsible for a higher mortality later in life, have been reported in obese children/adolescents. The aims of the study were to evaluate cardiovascular autonomic regulation, by means of spectrum analysis of R-R interval variability, and myocardial function, by means of standard and tissue Doppler echocardiography, in a group of non-hypertensive asymptomatic obese children and adolescents; furthermore, the influence of insulin resistance was tested.Subjects and Methods
R-R interval variability was analyzed during both the 70° head-up tilt and 24-hour electrocardiographic holter monitoring. Spectrum analysis of R-R interval variability provided the indices of sympathetic (low frequency [LFRR]) and vagal (high frequency [HFRR]) modulation of the sinoatrial node. Homeostasis model assessment of insulin resistance (HOMA-IR) was used to classify obese children/adolescents (n=72) as insulin resistant (n=37) and non-insulin resistant (n=35).Results
In obese subjects: a) left ventricular mass was significantly (p<0.05) increased, whereas both the e/a ratio and the e''/a'' ratio were decreased; b) at rest, HFRR was lower, and the LFRR/HFRR ratio was higher; c) during tilting, magnitude of tilt-induced inhibition of HFRR was lower; d) during 24-hour electrocardiographic holter monitoring, LFRR and the LFRR/HFRR ratio were higher, whereas HFRR was lower; e) HOMA-IR inversely correlated with both the e''/a'' ratio (r=-0.655; p<0.001) and the tilt-induced LFRR/HFRR ratio (r=-0.933; p<0.001); and, f) the e''/a'' ratio correlated with the tilt-induced LFRR/HFRR ratio (r=0.501; p<0.001). Moreover, HFRR at rest, magnitude of tilt-induced HFRR reduction, and the e''/a'' ratio in insulin resistant obese children/adolescents were markedly lower when compared with the remaining subjects.Conclusions
Subclinical abnormalities of myocardial function and of cardiac autonomic regulation were closely associated in obese children/adolescents and both correlated with the degree of insulin resistance. 相似文献80.
Giulia Maria Camerino Jean-Fran?ois Desaphy Michela De Bellis Roberta Francesca Capogrosso Anna Cozzoli Maria Maddalena Dinardo Roberta Caloiero Kejla Musaraj Adriano Fonzino Elena Conte Catherine Jagerschmidt Florence Namour Antonella Liantonio Annamaria De Luca Diana Conte Camerino Sabata Pierno 《PloS one》2015,10(6)
Muscle disuse produces severe atrophy and a slow-to-fast phenotype transition in the postural Soleus (Sol) muscle of rodents. Antioxidants, amino-acids and growth factors were ineffective to ameliorate muscle atrophy. Here we evaluate the effects of nandrolone (ND), an anabolic steroid, on mouse skeletal muscle atrophy induced by hindlimb unloading (HU). Mice were pre-treated for 2-weeks before HU and during the 2-weeks of HU. Muscle weight and total protein content were reduced in HU mice and a restoration of these parameters was found in ND-treated HU mice. The analysis of gene expression by real-time PCR demonstrates an increase of MuRF-1 during HU but minor involvement of other catabolic pathways. However, ND did not affect MuRF-1 expression. The evaluation of anabolic pathways showed no change in mTOR and eIF2-kinase mRNA expression, but the protein expression of the eukaryotic initiation factor eIF2 was reduced during HU and restored by ND. Moreover we found an involvement of regenerative pathways, since the increase of MyoD observed after HU suggests the promotion of myogenic stem cell differentiation in response to atrophy. At the same time, Notch-1 expression was down-regulated. Interestingly, the ND treatment prevented changes in MyoD and Notch-1 expression. On the contrary, there was no evidence for an effect of ND on the change of muscle phenotype induced by HU, since no effect of treatment was observed on the resting gCl, restCa and contractile properties in Sol muscle. Accordingly, PGC1α and myosin heavy chain expression, indexes of the phenotype transition, were not restored in ND-treated HU mice. We hypothesize that ND is unable to directly affect the phenotype transition when the specialized motor unit firing pattern of stimulation is lacking. Nevertheless, through stimulation of protein synthesis, ND preserves protein content and muscle weight, which may result advantageous to the affected skeletal muscle for functional recovery. 相似文献