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991.
992.
Our preliminary data suggested that 1,4-bis(1-naphthyl)-2,3-dinitro-1,3-butadiene [Viale M, Ottone M, Chiavarina B, Mariggiò MA, Prevosto C, Dell'Erba C, et al. Preliminary evaluation in vitro of the inhibition of cell proliferation, cytotoxicity and induction of apoptosis by 1,4-bis(1-naphthyl)-2,3-dinitro-1,3-butadiene. Invest New Drug 2004;22:359-67] (Naph-DNB), possesses good characteristics in terms of inhibition of cell proliferation in two cell lines derived from colon and gastric cancers. On this basis and to confirm the specificity of our compound towards gastrointestinal malignancies, we have analyzed the inhibition of cell proliferation, the cytotoxicity and the induction of apoptosis by Naph-DNB in seven cell lines derived from human colon (DLD-1, Lovo, HCT-8 and Colo 741), stomach (HGC-27) and pancreas (Panc-1 and Hup-T4) tumours. For the sake of comparison, cells have also been exposed to four anticancer drugs utilized for the treatment of gastrointestinal malignancies (oxaliplatin, irinotecan, gemcitabine and 5-fluorouracil). Moreover, toxicological data have been obtained in order to define the lethal dose (LD) and maximal tolerated dose (MTD) values and the spectrum of tissue alterations caused by the intraperitoneal (i.p.) and intravenous (i.v.) administration of Naph-DNB. IC50 data obtained by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay suggest that Naph-DNB is generally more active than two or more of the anticancer drugs above in most cell lines: it displayed the lowest activity only in HGC-27 cells, although data concerning the IC75 parameter enlighten a significantly better activity than irinotecan and 5-fluorouracil. Using the equitoxic concentrations IC50 and IC75, we have also evaluated the ability of Naph-DNB and of the other anticancer drugs to kill cells and to induce apoptosis. Our data show that at these concentrations Naph-DNB has a cytotoxic activity comparable or even better than that of some anticancer drugs. Similarly, Naph-DNB induces apoptosis better than the other anticancer drugs in HCT-8 and HGC-27 cells, while in Lovo and Panc-1 cells the induction is comparable. On the basis of toxicological data we defined the LD10, LD50, LD90 (i.p., 17.6, 36.1 and 54.1 mg kg(-1), respectively; i.v., 6.1, 14.1 and 22.0 mg kg(-1), respectively) and the MTD (i.p., 15 mg kg(-1); i.v., 5 mg kg(-1)) parameters. Histochemical analysis has shown that, in general, the administration of even toxic doses of Naph-DNB does not cause great structural injuries, although it can have some effects on the metabolism of glicogen and iron in organs as liver and spleen. In conclusion, our preclinical studies in vitro suggest that Naph-DNB may represent a good anticancer compound for the treatment of generally unresponsive tumours such as those of pancreas, stomach and colon. Moreover, the analysis of its toxic effects has allowed the definition of LD and MTD parameters, which will be used in further experiments in vivo for the definition of its antitumour activity.  相似文献   
993.
994.
Children and adolescents affected by ulcerative colitis (UC) frequently require colectomy because of refractory or chronic symptoms. The aim of this paper is to present our experience and 10-year follow-up results of 28 patients who underwent endorectal pull-through (ERPT) as surgical treatment for UC, with special regard to surgical complications, stooling patterns (frequency of defecation, stool consistency, urgency period), fecal incontinence, and quality of life. A retrospective chart review of these patients was performed to evaluate age at colectomy, indication for surgical treatment, operative procedures, technical details, and early or late complications. Frequency of defecation was less than twice per day in two patients, between three and five times per day in nine patients, and more than six times per day in 10 patients. Stool consistency was normal in 14 patients, loose in five, and liquid in only two cases. Urgency period was normal (minutes) in 14 patients, short (seconds) in four, and absent in three. Ten patients (47%) have perfect or good fecal continence, whereas 11 (52%) patients present moderate to total incontinence. The self-reported emotional health was good in most of the patients. A large number are progressing well at school and are coping with their operations. Studies of quality of life in UC patients who underwent surgical treatment in childhood or adolescence, comparing as well the results according to the surgical technique adopted, must be encouraged.  相似文献   
995.
Stratton and Parker [1989] described a 17-month-old boy with the previously unreported combination of growth hormone (GH) deficiency, Wormian bones, mild developmental delay, brachycamptodactyly, heart defects, kidney hypoplasia, imperforate anus, bilateral cryptorchidism, and facial anomalies. A similar case was later reported by Gabrielli et al. [1994], who suggested the existence of a "Stratton-Parker syndrome." Here, we describe a boy with isolated GH deficiency, body asymmetry, and brachycamptodactyly. At birth, complete anorectal agenesis and cryptorchidism were detected, which required surgical treatment. Radiographic examination showed the presence of bilateral proximal radioulnar subluxation and Kirner anomaly. Brain MRI showed asymmetry of the posterior horns of the lateral ventricles and enlarged cisterna magna. Psychomotor development had been mildly delayed during the first years of life. Due to the unique association of GH deficiency with intestinal, genital, and limbs abnormalities, we believe that our patient may represent a further case of Stratton-Parker syndrome. All patients reported, till date, are sporadic males born to healthy nonconsanguineous parents. X-linked recessive inheritance is a possibility to consider.  相似文献   
996.
997.
Leucine-rich repeats (LRRs) are versatile binding motifs found in a variety of proteins and are involved in protein-protein interactions. The LRR domain is composed of repeats forming a characteristic solenoid horse-shoe structure, which provides a scaffold for numerous insertions involved in binding to pathogen-associated molecular patterns and surface receptors. LRRs have been shown to be involved in the host defense systems of both plants (resistance genes) and mammals (Toll-like receptors and nucleotide-binding oligomerisation domain proteins), where they sense specific pathogen-associated molecules and activate the innate immune system. Paradoxically, LRRs have also been shown to be part of microbial virulence factors involved in the interaction with host cells and establishment of infection. The potential of LRRs to bind a vast array of structurally unrelated ligands and their well-documented involvement in microbial pathogenesis make them a potential target for vaccines and new drugs. The recent identification of LRRs in the obligate intracellular protozoan parasite Leishmania and their participation in the macrophage-parasite interaction have added new insight into the role of LRRs in the host cell invasion.  相似文献   
998.
Schizophrenia (SCZD) or schizoaffective disorders are quite common features in patients with DiGeorge/velo-cardio-facial syndrome (DGS/VCFS) as a result of chromosome 22q11.2 aploinsufficiency. We evaluated the Nogo-66 receptor gene (RTN4R), which maps within the DGS/VCFS critical region, as a potential candidate for schizophrenia susceptibility. RTN4R encodes for a functional cell surface receptor, a glycosylphosphatidylinositol (GPI)-linked protein, with multiple leucine-rich repeats (LRR), which is implicated in axonal growth inhibition. One hundred and twenty unrelated Italian schizophrenic patients were screened for mutations in the RTN4R gene using denaturing high performance liquid chromatography (DHPLC). Three mutant alleles were detected, including two missense changes (c.355C>T; R119W and c.587G>A; R196H), and one synonymous codon variant (c.54G>A; L18L). The two schizophrenic patients with the missense changes were strongly resistant to the neuroleptic treatment at any dosage. Both missense changes were absent in 300 control subjects. Molecular modeling revealed that both changes lead to putative structural alterations of the native protein.  相似文献   
999.
1000.
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