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201.
Summary A comparative study was carried in two Italian cities: Cagliari and Perugia. Ninetten fungal genera were assessed in both stations. Some were the same airborne spores, while others were characteristic of the areas. From an analysis of the linear regression coefficients between the concentration of four fungal genera and some meteorological parameters both in Cagliari and Perugia, a highly significative positive correlation could be seen between the presence of airborneCladosporium spores and both mean and maximum temperature. The same significative correlations were obtained both in Cagliari and Perugia forDrechslera/Helminthosporium.  相似文献   
202.
End-to-side nerve coaptation brings regenerating axons from the donor to the recipient nerve. Several techniques have been used to perform coaptation: microsurgical sutures with and without opening a window into the epi(peri)neurial connective tissue; among these, window techniques have been proven more effective in inducing axonal regeneration. The authors developed a sutureless model of end-to-side coaptation in the rat upper limb. In 19 adult Wistar rats, the median and the ulnar nerves of the left arm were approached from the axillary region, the median nerve transected and the proximal stump sutured to the pectoral muscle to prevent regeneration. Animals were then randomly divided in two experimental groups (7 animals each, 5 animals acting as control): Group 1: the distal stump of the transected median nerve was fixed to the ulnar nerve by applying cyanoacrylate solution; Group 2: a small epineurial window was opened into the epineurium of the ulnar nerve, caring to avoid damage to the nerve fibres; the distal stump of the transected median nerve was then fixed to the ulnar nerve by applying cyanoacrylate solution. The grasping test for functional evaluation was repeated every 10–11 weeks starting from week-15, up to the sacrifice (week 36). At week 36, the animals were sacrificed and the regenerated nerves harvested and processed for morphological investigations (high-resolution light microscopy as well as stereological and morphometrical analysis). This study shows that a) cyanoacrylate in end-to-side coaptation produces scarless axon regeneration without toxic effects; b) axonal regeneration and myelination occur even without opening an epineurial window, but c) the window is related to a larger number of regenerating fibres, especially myelinated and mature, and better functional outcomes.  相似文献   
203.
TMEM16A/ANO1 is a calcium-activated chloride channel expressed in several types of epithelia and involved in various physiological processes, including proliferation and development. During mouse embryonic development, the expression of TMEM16A in the olfactory epithelium is dynamic. TMEM16A is expressed at the apical surface of the entire olfactory epithelium at embryonic day E12.5 while from E16.5 its expression is restricted to a region near the transition zone with the respiratory epithelium. To investigate whether TMEM16A plays a role in the development of the mouse olfactory epithelium, we obtained the first immunohistochemistry study comparing the morphological properties of the olfactory epithelium and nasal glands in TMEM16A-/- and TMEM16A+/+ littermate mice. A comparison between the expression of the olfactory marker protein and adenylyl cyclase III shows that genetic ablation of TMEM16A did not seem to affect the maturation of olfactory sensory neurons and their ciliary layer. As TMEM16A is expressed at the apical part of supporting cells and in their microvilli, we used ezrin and cytokeratin 8 as markers of microvilli and cell body of supporting cells, respectively, and found that morphology and development of supporting cells were similar in TMEM16A-/- and TMEM16A+/+ littermate mice. The average number of supporting cells, olfactory sensory neurons, horizontal and globose basal cells were not significantly different in the two types of mice. Moreover, we also observed that the morphology of Bowman’s glands, nasal septal glands and lateral nasal glands did not change in the absence of TMEM16A. Our results indicate that the development of mouse olfactory epithelium and nasal glands does not seem to be affected by the genetic ablation of TMEM16A.  相似文献   
204.
A detailed structural characterization of the biologically active 1-benzylpyridinium-4-aldoxime chloride and 1-phenacylpyridinium-4-aldoxime chloride was performed using NMR and vibrational and electronic spectroscopy, as well as X-ray diffraction. The complexes of these compounds with the aquapentacyanoferrate(II) ion were examined in solution, isolated as solids and characterized by elemental analysis, electronic, FT-IR and NMR spectral data. They were found to be mononuclear substituted pentacyanoferrates(II) containing the aldoxime group coordinated to the iron through the nitrogen atom. The complexes were also precipitated in the form of the respective zinc salts; the analysis of these complexes revealed a molar Fe/Zn ratio of 1, thus confirming the charge of the complex anions to be −2. The ionization constants of the aldoxime group in the free ligands and in the respective cyano complexes were also determined. Despite the presence of two donor sites in 1-phenacylpyridinium-4-aldoxime chloride, only the aldoxime group was found to be reactive.  相似文献   
205.
Laser irradiation in the 450 nm region brings about irreversible changes in the copper sites of Rhus vernicifera laccase and its type 2 Cu-depleted derivative. The absorption band at 614 nm disappears after ~ 2 hr of irradiation with a 200 mW laser beam; the amount of the paramagnetic detectable copper does not decrease, indicating no reduction of these types of copper. No apparent rearrangement of the protein backbone occurs, as ultaviolet dichroic spectra of the enzyme before and after the irradiation do not show appreciable differences. Stellacyanin is insensitive to laser radiation at any wavelength.  相似文献   
206.
The low energy dynamic of the enzyme Cu,Zn superoxide dismutase have been investigated by means of quasielastic neutron scattering in the temperature range 4-320 K. Below 200 K the scattering is purely elastic, while above this temperature a pronounced decrease in the elastic intensity is observed, together with the onset of a small quasielastic component. This behavior is similar to that previously observed in other more flexible globular proteins, and can be attributed to transitions between slightly different conformational substates of the protein tertiary structure. The presence of only a small quasielastic component, whose intensity is < or = 25% of the total spectrum, is related to the high structural rigidity of this protein.  相似文献   
207.
Pre-eclampsia (PE) is a multisystem disorder commonly diagnosed in the latter half of pregnancy and it is a leading cause of intrauterine fetal growth retardation (IUGR). The aim of this study was to investigate the localization and the role of SPARC, secreted protein acidic, and rich in cysteine, in PE and PE–IUGR placentas in comparison with normal placentas. SPARC was mainly expressed in the villous and extravillous cytotrophoblastic cells in first trimester, whereas in PE, PE–IUGR and at term placentas, SPARC immunostaining was visible in both cytotrophoblastic cells and syncytiotrophoblast. SPARC expression significantly decreased in normal placenta from first to third trimester and a further significant reduction was demonstrated in PE and PE–IUGR. The latter downregulation of SPARC depends on hypoxic condition as shown by in vitro models. In conclusion, SPARC can play a pivotal role in PE and PE–IUGR onset and it should be considered as a key molecule for future investigations in such pathologies.  相似文献   
208.
209.
A series of pyrrolo [2,3-d]pyridazinones was synthesized and tested for their inhibitory activity on PDE4 subtypes A, B and D and selectivity toward Rolipram high affinity binding site (HARBS). New agents with interesting profile were reported; in particular compound 9e showed a good PDE4 subtype selectivity, being 8 times more potent (IC50 = 0.32 microM) for PDE4B (anti-inflammatory) than for PDE4D (IC50 = 2.5 microM), generally considered the subtype responsible for emesis. Moreover the ratio HARBS/PDE4B was particularly favourable for 9e (147), suggesting that the best arranged groups around the pyrrolopyridazinone core are an isopropyl at position-1, an ethoxycarbonyl at position-2, together with an ethyl group at position-6. For compounds 8 and 15a the ability to inhibit TNFalpha production in PBMC was evaluated and the results are consistent with their PDE4 inhibitory activity.  相似文献   
210.
Fluctuation in extracellular calcium (Ca(2+)) concentration occurs during bone remodeling. Free ionized Ca(2+) plays a critical role in regulating osteoblast functions. We analyzed the effects of different concentrations of free ionized Ca(2+) (0.5, 1.3, and 2.6 mM) on human osteoblasts and we evaluated osteoblastic phenotype (marker expression and cell morphology) and functions (osteogenic differentiation, cell proliferation, and cell signaling). Our data show human osteoblasts that chronically stimulated with 0.5, 1.3, or 2.6 mM Ca(2+) significantly increase intracellular content of alkaline phosphatase, collagen type I, osteocalcin, and bone sialoprotein, whereas collagen type XV was down-modulated and RUNX2 expression was not affected. We also found a Ca(2+) concentration-dependent increase in osteogenic differentiation and cell proliferation, associated to an increase of signaling protein PLCβ1 and p-ERK. Human osteoblast morphology was affected by Ca(2+) as seen by the presence of numerous nucleoli, cells in mitosis, cell junctions, and an increased number of vacuoles. In conclusion, our data show a clear phenotypical and functional effect of extracellular Ca(2+) on human osteoblasts and support the hypothesis of a direct role of this cation in the bone remodeling processes.  相似文献   
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