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11.
Lucia Rosaria De Vitis Andrea Tedde Francesca Vitelli Franco Ammannati Pasquale Mennonna Umberto Bigozzi Enrico Montali Laura Papi 《Human genetics》1996,97(5):632-637
Meningiomas are benign tumors of the central nervous system. They are usually sporadic but can also occur associated with the neurofibromatosis type 2 (NF2) syndrome. The gene responsible for NF2, recently isolated from chromosome 22, encodes a membrane-organizing protein that shows high sequence homology to a protein family thought to link the cytoskeleton with membrane proteins. Mutations of the NF2 gene have been described in sporadic meningiomas, exclusively in tumors that show loss of heterozygosity (LOH) of 22q. These preliminary results indicate that the NF2 gene is involved in the pathogenesis of at least a subset of meningiomas, where it does indeed behave as a tumor suppressor gene. In order to characterize better the role of the NF2 gene in the genesis of meningiomas we have examined the entire coding sequence of the gene in 125 meningiomas by single-strand conformational polymorphism analysis; furthermore, LOH analysis for markers of 22q has been carried out. Inactivating mutations were identified in 30% of our samples, all of which also showed LOH of 22q. The majority of mutations identified were frameshifts and nonsense mutations, which are predicted to produce a truncated or non-functional protein. We also found two missense and three in-frame deletions that may pinpoint specific regions of the protein critical to its function. Furthermore, the distribution of mutations throughout the gene, suggested that exons 2, 3, 5, 11 and 13 are more frequently involved. Our results reconfirm the importance of the NF2 gene in the pathogenesis of meningiomas and also suggest that there may be a nonrandom clustering of mutations throughout the gene. 相似文献
12.
A preliminary report on the use of transfer factor for treating stage D3 hormone-unresponsive metastatic prostate cancer 总被引:4,自引:0,他引:4
Dr. Giancarlo Pizza Caterina De Vinci Diego Cuzzocrea Domenico Menniti Ernesto Aiello Paolo Maver Giuseppe Corrado Piero Romagnoli Ennio Dragoni Giuseppe LoConte Umberto Riolo Aldopaolo Palareti Paolo Zucchelli Vittorio Fornarola Dimitri Viza 《Biotherapy》1996,9(1-3):123-132
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have
suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA).
These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able
to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one
intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission
was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was
126 weeks, higher than the survival rates reported in the literature for patients of the same stage. 相似文献
13.
14.
Guano F Bernardi R Negri C Donzelli M Prosperi E Ricotti GA Scovassi AI 《Cell death and differentiation》1994,1(2):101-107
Zinc ions exert an inhibitory effect on Ca(2+)Mg(2+)-dependent endonuclease which is supposed to be responsible for the fragmentation of DNA during apoptosis. In the experimental system we used, that is HeLa cells treated with VP-16, the protection from internucleosomal DNA degradation is modulated by Zn concentration and appears to be dependent on the time after treatment. This effect does not prevent cell death or occurrence of apoptotic parameters, suggesting that DNA ladder appearance is not a crucial event in apoptosis. The activation of poly(ADP-ribose)polymerase following the administration of VP-16, is not observed in cells in which DNA fragmentation has been abolished by zinc, supporting the hypothesis that this event is regulated by the appearance of small-sized DNA fragments. 相似文献
15.
Regeneration of Fertile Barley Plants from Mechanically Isolated Protoplasts of the Fertilized Egg Cell 总被引:20,自引:0,他引:20 下载免费PDF全文
A simple procedure is described for the mechanical isolation of protoplasts of unfertilized and fertilized barley egg cells from dissected ovules. Viable protoplasts were isolated from ~75% of the dissected ovules. Unfertilized protoplasts did not divide, whereas almost all fertilized protoplasts developed into microcalli. These degenerated when grown in medium only. When cocultivated with barley microspores undergoing microspore embryogenesis, the protoplasts of the fertilized egg cells developed into embryo-like structures that gave rise to fully fertile plants. On average, 75% of cocultivated protoplasts of fertilized egg cells developed into embryo-like structures. Fully fertile plants were regenerated from ~50% of the embryo-like structures. The isolation-regeneration techniques may be largely genotype independent, because similar frequencies were obtained in two different barley varieties with very different performance in anther and microspore culture. Protoplasts of unfertilized and fertilized eggs of wheat were isolated by the same procedure, and a fully fertile wheat plant was regenerated by cocultivation with barley microspores. 相似文献
16.
Umberto Belluco Roberta Bertani Rino A. Michelin Mirto Mozzon Franco Benetollo Gabriella Bombieri Robert J. Angelici 《Inorganica chimica acta》1995,240(1-2):567-574
The chloro complexes trans-[Pt(Me)(Cl)(PPh3)2], after treatment with AgBF4, react with 1-alkynes HC---C---R in the presence of NEt3 to afford the corresponding acetylide derivatives trans-[Pt(Me) (C---C---R) (PPh3)2] (R = p-tolyl (1), Ph (2), C(CH3)3 (3)). These complexes, with the exception of the t-butylacetylide complex, react with the chloroalcohols HO(CH2)nCl (n = 2, 3) in the presence of 1 equiv. of HBF4 to afford the alkyl(chloroalkoxy)carbene complexes trans-[Pt(Me) {C[O(CH2)nCl](CH2R) } (PPh3)2][BF4] (R = p-tolyl, N = 2 (4), N = 3 (5); R=Ph, N = 2 (6)). A similar reaction of the bis(acetylide) complex trans-[Pt(C---C---Ph)2(PMe2Ph)2] with 2 equiv. HBF4 and 3-chloro-1-propanol affords trans-[Pt(C---CPh) {C(OCH2CH2CH2Cl)(CH2Ph) } (PMe2Ph)2][BF4] (7). T alkyl(chloroalkoxy)-carbene complex trans-[Pt(Me) {C(OCH2CH2Cl)(CH2Ph) } (PPh3)2][BF4] (8) is formed by reaction of trans-[Pt(Me)(Cl)(PPh3)2], after treatment with AgBF4 in HOCH2CH2Cl, with phenylacetylene in the presence of 1 equiv. of n-BuLi. The reaction of the dimer [Pt(Cl)(μ-Cl)(PMe2Ph)]2 with p-tolylacetylene and 3-chloro-1-propanol yields cis-[PtCl2{C(OCH2CH2CH2Cl)(CH2C6H4-p-Me}(PMe2Ph)] (9). The X-ray molecular structure of (8) has been determined. It crystallizes in the orthorhombic system, space group Pna21, with a = 11.785(2), B = 29.418(4), C = 15.409(3) Å, V = 4889(1) Å3 and Z = 4. The carbene ligand is perpendicular to the Pt(II) coordination plane; the PtC(carbene) bond distance is 2.01(1) Å and the short C(carbene)-O bond distance of 1.30(1) Å suggests extensive electronic delocalization within the Pt---C(carbene)---O moietry. 相似文献
17.
The inhibitory action of oligomycin on State-4 respiration in rat-liver mitochondria has been investigated in detail with regard to the extent, mode and characteristics of the inhibition. The possibility that this effect may be due either to some damage of the mitochondrial preparation used or to the presence of heavy contaminations by microsomes has been excluded. It has been found that the concentration of specific binding sites is the same in State 4 as in State 3. The extent of the inhibition appears to be related to the ADP concentration, rather than to ratios. The inhibition of this antibiotic on State-4 respiration does not depend on the experimental conditions used (i.e., choice of substrates or composition of the reaction medium). In agreement with these observations, it has been found that the membrane potential of State 4 is significantly increased when oligomycin is added. All these results provide further evidence to the conclusion that a large portion of State-4 respiration is linked to phosphorylation. 相似文献
18.
Sauvagine, a linear peptide of 40 amino acids, produced hypotension when administered intravenously to anesthetized dogs. Diastolic pressure was always more affected than systolic pressure. Aortic blood flow and venous return both increased to the same extent. The mechanism of the hypotensive response was mainly, if not exclusively, due to dilatation of the superior and inferior mesenteric arteries. Intravenous infusion of sauvagine in doses ranging from 3 to 10 ng · kg?1 · min?1 produced a dose-related increased of mesenteric blood flow up to 400% control values. Mucosal-submucosal blood flow of ileum and colon was increased, while blood flow in muscle was unaffected or slight decreased. The mesenteric vasodilator response was not prevented by adrenergic or muscarinic receptor blockade. The hypotensive response was more marked and sustained in dibenamine-propranolol treated dogs. 相似文献
19.
Natale Cascinelli Gian Paolo Balzarini Vincenzo Fontana Sergio Orefice Umberto Veronesi 《Cancer immunology, immunotherapy : CII》1977,2(3):157-161
Summary From November 1973 to December 1974, 20 patients with advanced malignant melanoma were treated with BCG given by intralymphatic route at the Cancer Institute of Milan. The lyophilized Pasteur BCG was used. Patients were treated with a single dose ranging from 0.2–80 mg. Patients' performance status was never severely impaired.The most frequent side effects were fever, lymphangitis, and lymph node enlargement.Variations were observed in white cell count, ERS and immunoglobulins; in no case did we find evidence of liver toxicity or tumor growth enhancement. It is concluded that the intralymphatic route is a safe way of administrating BCG. 相似文献
20.
Masini A Ceccarelli-Stanzani D Muscatello U 《Journal of bioenergetics and biomembranes》1983,15(4):217-234
A possible relationship between mitochondrial Mg2+ levels, structural configurations, and functional steady states has been studied in rat liver mitochondria. The results show that the concentration of mitochondrial Mg2+ in respiratory state 4 is definitely higher than in respiratory state 3. The metabolic transition from state 3 to state 4 and vice-versa is associated with reversible influx-efflux of about 10 nmol of Mg2+ per mg protein. The net uptake of this aliquot of Mg2+ is a necessary condition in order for the metabolic transition to state 4, both structurally and functionally, to occur. This process requires a threshold concentration of external Mg2+ greater than 5 mM. The phosphorylative mechanism does not appear to depend on the presence or absence of external Mg2+. The role of Mg2+ on the attainment and maintenance of the structural and functional steady state 4 seems to be correlated with its regulatory effect on the concentration of the mitochondrial Pi. 相似文献