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Biochar produced from pellet obtained from grapevine (GV) and sunflower husk (SFH) at different temperature (400 and 500°C) were studied by pyrolysis batch reactor. Chemical and physical evolution of biomass under pyrolysis conditions was determined and products characterization was evaluated, including main organic components in gaseous stream. The Biochar is a “porous carbonaceous solid” produced by thermochemical conversion of organic materials in an oxygen depleted atmosphere, which has physiochemical properties suitable for the safe and long-term storage of carbon in the environment and, potentially, soil improvement. Results have shown a decrease in yield as an increase in temperature. The objective of this work is to improve the acknowledgment for the alternative use of the biochar gained from agro-forestry biomass residuals grapevine and sunflower husks by means of modern chemical and physical characterization tools.

Phenomena related to an alternate means of preparing steel for discontinuous hot dip galvanizing using aluminum-containing galvanizing baths are presented in this paper, using electroless deposition of thin layers of Ni-P as a steel pretreatment before immersion in molten Zn-5 % Al alloy. By this means, the use of fluxes is eliminated. The greater chemical affinity of Ni to Al, compared with Fe and Zn, allows for control of the role of Al in the galvanizing reaction.

Myosin VI (MVI) is a dimeric molecular motor that translocates backwards on actin filaments with a surprisingly large and variable step size, given its short lever arm. A recent x-ray structure of MVI indicates that the large step size can be explained in part by a novel conformation of the converter subdomain in the prepowerstroke state, in which a 53-residue insert, unique to MVI, reorients the lever arm nearly parallel to the actin filament. To determine whether the existence of the novel converter conformation could contribute to the step-size variability, we used a path-based free-energy simulation tool, the string method, to show that there is a small free-energy difference between the novel converter conformation and the conventional conformation found in other myosins. This result suggests that MVI can bind to actin with the converter in either conformation. Models of MVI/MV chimeric dimers show that the variability in the tilting angle of the lever arm that results from the two converter conformations can lead to step-size variations of ∼12 nm. These variations, in combination with other proposed mechanisms, could explain the experimentally determined step-size variability of ∼25 nm for wild-type MVI. Mutations to test the findings by experiment are suggested.

A fragment-based docking procedure followed by substructure search were used to identify active-site β-secretase inhibitors from a composite set of about 300 000 and a library of nearly 180 000 small molecules, respectively. EC50 values less than 10 μM were measured in at least one of two different mammalian cell-based assays for 12 of the 72 purchased compounds. In particular, the phenylureathiadiazole 2 and the diphenylurea derivative 3 are promising lead compounds for β-secretase inhibition.

Abstract Two genetically related strains of Tuber borchii Vittad. (1BO and 43BO) produce mycorrhizas with Tilia platyphyllos Scop. with a different degree of efficiency. The aim of this work was to characterize the morphology of the fungal symbiotic structures in order to examine potential relationships between the anatomical traits of the mycorrhiza, the mycorrhizal capacities of the fungal strains and their effect on the host plants. Some morphological features of mantle hyphae (small size, intense staining, vacuolization, abundance of mitochondria) led to a mantle with morphological features that were isolate-specific. There were unexpected differences, at least under our experimental conditions: 1BO strain mantle cells were larger, less reactive to staining, more highly vacuolated and poorer in mitochondria than those of 43BO. These features were found throughout the mantle in 1BO, while the inner mantle hyphae of 43BO were significantly smaller and more intensely stained than the outer cells. In the 43BO strain there was a positive relation between these features and higher infectivity (evaluated as percentage of mycorrhizal tips) as well as a slightly more effective stimulation of plant growth. These observations suggest that genetically related truffle strains produce mycorrhizas with different morphologies, which may be related to a more efficient response of the host plant to inoculation.

Abstract:  Tilia platyphyllos Scop. plantlets were inoculated in vitro with five Tuber borchii Vittad. strains (1BO, 17BO, 43BO, 71BO and 10RA) to test their intraspecific variability. The ability of the strains to form mycorrhizas varied, with the mean degree of ectomycorrhizal infection ranging from 50.6% (for 1BO) to 82.1% (for 10RA). The anatomical/morphological characteristics of the resulting mycorrhizas were determined. Although the morphological features of the mycorrhizas and the characteristics of the cystidia were similar for all strains tested, differences were found in the anatomical features of the mantle. The form of the mantle cells was examined in the surface and inner layers (6 and 12 μm deep, respectively) by both conventional and confocal microscopy. These cells were polygonal in 1BO, and 71BO, epidermoid in 43BO and intermediate in 17BO and 10RA. The structure of the mantle also varied and thus provided little information with which to identify T. borchii mycorrhizas.

Colony-stimulating factor-1 (CSF-1), also called macrophage colony-stimulating factor, is the growth factor for the cells of the mononuclear phagocytic system. Further-more, CSF-1 is essential in osteoclastogenesis and also affects mature osteoclasts. The receptor for CSF-1 was demonstrated on cells of the osteoclast lineage, with highest levels on the mature cells. This study investigated whether the binding of CSF-1 to isolated rat osteoclasts is modulated by the growth factor itself. Exposure of osteoclasts to CSF-1 for 1 hour virtually abolished binding of the growth factor. After removal of CSF-1, binding sites were restored within 4 hours. This recovery was blocked by cycloheximide, indicating the dependence on new protein synthesis for reex-pression of receptors on the cell surface. The observed downregulation of CSF-1 binding sites might be a mechanism to control the effects of the growth factor on mature osteoclasts.

Colony stimulating factor-1 (CSF-1) regulates the survival, proliferation and differentiation of mononuclear phagocytes. The osteopetrotic (op/op) mutant mouse is devoid of CSF-1 due to an inactivating mutation in the CSF-1 gene and is deficient in several mononuclear phagocyte subpopulations. To analyze more fully the requirement for CSF-1 in the establishment and maintenance of mononuclear phagocytes, the postnatal development of cells bearing the macrophage marker antigens F4/80 and MOMA-1, in op/op mice and their normal (+/op or +/+) littermates, were studied during the first three months of life. In normal mice, maximum expression of tissue F4/80+ cells was generally correlated with the period of maximum organogenesis and/or cell turnover. Depending on the tissue, the F4/80+ cell density either decreased, transiently increased or gradually increased with age. In op/op mice, tissues that normally contain F4/80+ cells could be classified into those in which F4/80+ cells were absent and those in which the F4/80+ cell densities were either reduced, normal or initially normal then subsequently reduced. To assess which F4/80+ populations were regulated by circulating CSF-1 in normal mice, op/op mice in which the circulating CSF-1 concentration was restored to above normal levels by daily subcutaneous injection of human recombinant CSF-1 from day 3 were analyzed. These studies suggest that circulating CSF-1 exclusively regulates both the F4/80+ cells in the liver, spleen and kidney and the MOMA-1+ metallophilic macrophages in the spleen. Macrophages of the dermis, bladder, bone marrow and salivary gland, together with a subpopulation in the gut, were partially restored by circulating CSF-1, whereas macrophages of the muscle, tendon, periosteum, synovial membrane, adrenals and the macrophages intimately associated with the epithelia of the digestive tract, were not corrected by restoration of circulating CSF-1, suggesting that they are exclusively locally regulated by this growth factor. Langerhans cells, bone marrow monocytes and macrophages of the thymus and lymph nodes were not significantly affected by circulating CSF-1 nor decreased in op/op mice, consistent with their regulation by other growth factors. These results indicate that important differences exist among mononuclear phagocytes in their dependency on CSF-1 and the way in which CSF-1 is presented to them. They also suggest that the prevalent role of CSF-1 is to influence organogenesis and tissue turnover by stimulating the production of tissue macrophages with local trophic and/or scavenger (physiological) functions. Macrophages involved in inflammatory and immune (pathological) responses appear to be dependent on other factors for their ontogenesis and function.(ABSTRACT TRUNCATED AT 400 WORDS)

This study was carried out to determine whether bone might be a source of hemopoietic growth factors. Both neonatal murine calvaria and primary cultures of cells isolated from calvaria released, upon stimulation with lipopolysaccharide, an activity that stimulated the growth of the interleukin (IL) 3‐dependent cell lines, 32D cl, 123, and NSF 60. Upon gel filtration, this activity eluted with a molecular weight of 30,000 kDa. Further characterization, however, revealed that the major activity in conditioned medium was not IL 3. Activity was absorbed by DEAE‐Sephacel at low salt concentration, whereas IL 3 does not adhere. Furthermore, an IL 3‐specific antiserum did not neutralize the activity from cells and only partly neutralized the activity generated by whole calvaria. After gel filtration, the 30‐kDa activity stimulated the growth of very large colonies in semisolid medium consisting mainly of granulocytes with the remainder being macrophages. No colony types belonging to other hemopoietic lineages were found, indicating, again, that the activity was not identical to IL 3. Subsequently, conditioned medium was fractionated by hydrophobic chromatography on Phenyl‐Sepharose CL‐4B, yielding two peaks of activity. Neutralization of activity with antisera to granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) and IL 3 and use of colony assays showed that medium conditioned by whole calvaria contained GM‐CSF and granulocyte CSF (G‐CSF) in similar amounts together with a little IL 3, and medium conditioned with calvaria cells contained GM‐CSF and little G‐CSF. We conclude that bone releases hemopoietic growth factors that could contribute both to hemopoiesis and to the recruitment of osteoclasts from progenitors resident in the adjacent marrow.

Macrophage colony-stimulating factor (M-CSF), whose action is restricted to the cell populations of the mononuclear phagocyte system, has recently been found to be required for osteoclastogenesis and bone resorption. To investigate the cells involved in the action of M-CSF in these processes, expression of c-fms mRNA, encoding the M-CSF receptor, was studied by in situ hybridization. Paws from murine embryos and newborn mice, tibiae from 2-day-old animals, as well as isolated osteoclasts, were hybridized with a c-fms-specific RNA probe. In bone, c-fms mRNA was detected only in cells at the late stages of osteoclastogenesis and in mature osteoclasts. The findings strengthen the relation between osteoclasts and the mononuclear phagocyte system. Furthermore, they suggest that M-CSF acts directly on osteoclast precursors and on mature osteoclasts during osteoclastogenesis.

We studied the effect of recombinant human granulocyte colony- stimulating factor (rhG-CSF) administration to pregnant rats upon fetal and neonatal myelopoiesis. Pregnant rats were treated with rhG-CSF twice daily for 2, 4, and 6 days before parturition. rhG-CSF crossed the placenta and reached peak fetal serum concentrations 4 hours after administration. Peak fetal serum levels were 1,000-fold lower than levels detected in the dam. Hematopoietic effects of rhG-CSF were assessed by cytologic analysis of the newborn blood, spleen, bone marrow, thymus, and liver. White blood cell counts were increased twofold to fourfold in newborns. This increase was due to circulating numbers of polymorphonuclear cells (PMN). rhG-CSF induced a myeloid hyperplasia in the newborn marrow consisting of immature and mature myeloid cells in the day-2 and day-4 treated pups. Bone marrow of pups treated for 6 days contained mostly hyper-segmented PMN with little or no increase in myeloid precursors. An increase in the number of postmitotic (PMN, bands, and metamyelocytes) and mitotic (promyeloblasts, myeloblasts, and metamyeloblasts) myeloid cells in the spleen of neonates was observed. No change was detected in splenic lymphocytes or monocytes. No effect of rhG-CSF was noted in the newborn liver or thymus. These results demonstrate that maternally administered rhG-CSF crosses the placenta and specifically induces bone marrow and spleen myelopoiesis in the fetus and neonate. The significant myelopoietic effects of rhG-CSF at low concentrations in the fetus suggest an exquisite degree of developmental sensitivity to this cytokine and may provide enhanced defense mechanisms to the neonate.

Summary: The osteoclast may be of hematopoietic lineage and as such its development could be regulated by colony-stimulating factors. Since there is much interest as to whether osteoblasts influence bone resorption, we examined whether bone cells produce colony-stimulating activity. Both cells isolated from neonatal calvaria and the osteogenic cell MC3T3-E1 were found to constitutively release a colony-stimulating activity possessing characteristics of a macrophage colony-stimulating factor, as determined by basic biochemical purification and by identity of colonies induced in cultures of bone marrow cells. Release could be increased by the presence of the bone-resorbing agents lipopolysaccharide and 1,25 dihydroxyvitamin D3. We conclude that the osteoblast may contribute to both the processes of osteoclast formation and of hematopoiesis through the secretion of colony-stimulating activity into the adjacent bone marrow.

137 Cs activity in samples from lacustrine areas around the Italian base in Antarctica is reported as an integration of a previous work. Preliminary data of cosmogenic 7 Be activity determined in snowfalls, total atmospheric depositions, soil and air particulate collected during the 1990-91 and 1991-92 Italian expeditions in Antarctica is presented. The results obtained point out the efficiency of snow in the processes of air particulate scavenging and provide useful information for the development of research in Antarctica in the study of air/snow transfer processes by means of natural radionuclides.

The seasonal evolution of the cadmium and lead distribution in the water column of the Gerlache Inlet (Ross Sea) was studied during the 1990-91 austral summer. Measurements were carried out by Anodic Stripping Voltammetry in Antarctica immediately after the collection and filtration of samples. The concentrations of both metals were homogeneous before the phytoplankton bloom with mean values of 0.71 (SD 0.10) and 0.116 (SD 0.014) nmol/1 for cadmium and lead respectively. A subsequent depletion in metal concentration was observed in the shallow waters. The surface concentration of cadmium decreased to about 0.1 nmol/1 at the end of the season. The vertical distribution of lead was less affected by the seasonal evolution and the mean surface concentration decreased to 0.044 nmol/1 in the same period. The results are evaluated with respect to physical and biological processes in the area examined and compared with those obtained on previous expeditions in the same area.

The aim of this study was to investigate the possible inhibitory effect of ipriflavone on bone resorption in rats. For this purpose, 10-week-old, intact and ovariectomized (OVX) rats, prelabeled from birth with [3H]tetracycline, were used. Bone resorption was monitored by measuring the urinary excretion of [3H]. The animals were fed a purified diet devoid of naturally occurring flavonoids. In the intact rats, the daily meal was given either as a single portion or divided into four portions, a procedure known to lead by itself to a decrease in bone resorption. Ipriflavone, given 7 days after OVX at the dose of 400 mg/kg B.W. daily mixed with the food, led within 2–3 days to a significant decrease in bone resorption equivalent to that of 27.2 μg/kg S.C. of 17β-estradiol. The inhibition was sustained for the length of the experiment, up to 21 days. Ipriflavone given 7 days before OVX prevented the increase in bone resorption induced by castration, the effect being dose-dependent between 50 and 400 mg/kg B.W. In contrast to 17β-estradiol, a 5-week treatment with ipriflavone failed to prevent the OVX-induced uterine atrophy. Significant inhibition of bone resorption was also seen in intact animals, provided they rapidly ingested the daily meal. Actually, the decrease in bone resorption induced by portioning the daily food masked the inhibitory effect of ipriflavone in intact animals. In conclusion, ipriflavone can decrease bone resorption in both intact and OVX animals given a purified diet as a single daily meal. In the OVX model, ipriflavone mimics the osteoprotective effect of estrogen. However, the lack of a uterotropic effect suggests that the compound can discriminate between bone and reproductive tissues.

The calcitonin (CT) concentration has been determined in the serum of 17 patients with different pituitary diseases. More or less elevated levels were found in 7 of them. No definite correlation has been observed between the immunoreactive CT and the different pituitary hormones.

The effect of GM-CSF infused after 7g/m2cyclophosphamide (CTX) and 800mg/m2carboplatinum (CBDCA) was evaluated in 16 (LGNHL, MM, HD) patients. Serum concentrations of soluble CD8 (sCD8) and soluble IL-2 receptor (sIL-2R) as well as circulating levels of IL-2, IFN-γ, neopterin, IL-1α, ILl-β, TNF-α and IL-6 were determined on day 0 and days +4, +10 and +16 post-GM-CSF and intracellular IL-2, IFN-γ, IL-1α, IL1-β, TNF-α and IL-6 on days 0 and +16. sIL-2 R rose from day +4 to day + 16 and reached twice basal values at 10 and 16 days after both CTX (2266±904, 2292±873 vs 1189±608) and CBDCA (2225±965, 2313±1055 vs 1151±518). Neopterin also rose and was maximum on day +16 (1.7 post-CTX, 1.6 post-CBDCA vs basal). Serum IL-1α concentrations varied little after CTX, but increased two-fold over basal values after CBDCA (39.3±34.6 vs 15.8±40.5). Serum IL-1β increased 1.3 on the 16th post-GM-CSF day after CTX and 1.8 after CBDCA. Serum TNF-α rose to 1.8 basal values on day +10 and to 3.5 on day +16 following CBDCA, but not after CTX. Changes in the other serum and intracellular indices studied were negligible. These results suggest that GM-CSF activates T-Iymphocytes and macrophages, but that their activation partially depends on the therapy that precedes administration of the growth factor.

The peripheral blood stem cell (PBSC) mobilization capacity of carboplatin (CBOCA, 800mg/m2) followed by GM-CSF infusion (5μg/kg) is being compared with that of cyclophosphamide (CTX, 7g/m2) followed by the same dose of GM-CSE. So far, 18 patients, 5 MM, 9 LG-NHL, 4 HD, have been entered in the study. PBSC were not collected after CBDCA in 4 cases, one due to early discharge, one because of suspected, but unconfirmed, allergy to GM-CSF, one because the CBOCA dose was reduced to 400mg/m2, one because G-CSF was substituted for GM-CSF due to hypotension and dyspnea, which, however reappeared 3 times while patient was off treatment. 53 stemophereses were analyzed in the other 14 patients after CTX and 43 after CBOCA for a mean of 6.8/patient. Mean CFU-GM×106/I recovered were 0.34±0.2 after CBOCA and 0.58±0.78 after CTX (P=NS). Mean CD34+×106/I were 35.9±118 after CBOCA and 24±34.4 after CTX (P=00034). Multifactorial analysis performed to identify the variables that influence CFU-GM×106/1 and CD34+×106/1 recovery revealed that the relevant factors for CFU-GM were: the CFU-GM/ml, the percentage and absolute values of CD34+/ml in the peripheral blood the day stemopheresis was effected, the type of disease, the number of bone marrow CFU-GM befure starting therapy (bone-marrow proliferations). For CD34+ they were: the WBC/1, the percentage and absolute values of CD34+/ml present on the day of stemopheresis, the type of disease and the bone-marrow proliferation before starting therapy.