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1.
Rocío García-Pérez Beatriz Revilla-Nuin Carlos M. Martínez Angel Bernabé-García Alberto Baroja Mazo Pascual Parrilla Paricio 《PloS one》2015,10(12)
Associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a two-stage hepatectomy technique which can be associated with a hypertrophic stimulus on the future liver remnant (FLR) stronger than other techniques–such as portal vein ligation (PVL). However, the reason of such hypertrophy is still unclear, but it is suggested that liver transection combined with portal vein ligation (ALPPS) during the first stage of this technique may play a key role. The aim of this study is to compare the hypertrophic stimulus on the FLR and the clinical changes associated with both ALPPS and PVL in a rat surgical model. For this purpose, three groups of SD rats were used, namely ALPPS (n = 30), PVL (n = 30) and sham-treated (n = 30). The second stage of ALPPS (hepatectomy of the atrophic lobes), was performed at day 8. Blood and FLR samples were collected at 1, 24, 48 hours, 8 days and 12 weeks after the surgeries. ALPPS provoked a greater degree of hypertrophy of the FLR than the PVL at 48 hours and 8 days (p<0.05). The molecular pattern was also different, with the highest expression of IL-1β at 24h, IL-6 at 8 days, and HGF and TNF-α at 48 hours and 8 days (p<0.05). ALPPS also brought about a mild proliferative stimulus at 12 weeks, with a higher expression of HGF and TGF-β (p<0.05) than PVL. Clinically, ALPPS caused a significant liver damage during the first 48 hours, with a recovery of liver function at day 8. In conclusion, ALPPS seems to induce higher functional hypertrophy on the FLR than PVL at day 8. Such regenerative response seems to be leaded by a complex interaction between pro-mitogenic (IL-6, HGF, TNF-α) and antiproliferative (IL1-β and TGF-β) cytokines. 相似文献
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Raúl Castaño Angel Ezquerra Nieves Doménech José A. López de Castro 《Immunogenetics》1988,27(5):345-355
The HLA-A2 antigen expressed by donor OZB can be distinguished from the main HLA-A2.1 subtype by isoelectric focusing - it is one charge unit more acidic — and by some alloreactive T-cell clones but not by cytolytic T lymphocyte lines. The structure of variant OZB has been examined by comparative peptide mapping with A2.1 and radiochemical sequence analysis. The two molecules were found to differ in a single tryptic peptide from the 0 region, spanning residues 220–243. The amino acid sequence of this peptide from variant OZB revealed that there was only one amino acid change of Glu instead of Ala at position 236, a hitherto invariant residue in class I HLA antigens. All previously characterized HLA or H-2 natural variants have structural changes restricted to the 1 and/or 2 domains. Thus, variant OZB is unique in that (1) it has one amino acid change in 3 and (2) it has no changes in l and 2. The only detected substitution of this variant may be accounted for by a single base change at the DNA level, suggesting that it might have resulted from a point mutation in the A2.1 gene. The structural features of variant OZB open a novel way to examine the influence of polymorphism in 3 on cytolytic T-cell recognition of naturally occurring class I antigens.Abbreviations CTL
cytolytic T lymphocytes
- HPLC
high performance liquid chromatography
- IEF
isoelectric focusing
- MHC
major histocompatibility complex 相似文献
5.
The critical relationship between free radicals and degrees of ischemia: evidence for tissue intolerance of marginal perfusion 总被引:8,自引:0,他引:8
M F Angel S S Ramasastry W M Swartz K Narayanan D B Kuhns R E Basford J W Futrell 《Plastic and reconstructive surgery》1988,81(2):233-239
Skin-flap ischemia has been associated with the presence of free radicals. In this study, two enzyme systems involved in free-radical metabolism were used to compare a distal skin flap to a skin graft. Forty-two rats were divided into several test groups. A 10 X 3 cm dorsal rat flap was used, and tissue biopsies for xanthine oxidase and malonyldialdehyde (MDA) were obtained 2.5, 5.5, and 8.5 cm from the base of the flap at the hours given. In group I (control), the flap was outlined but not elevated, and biopsies were obtained. In group II, the flap was elevated, and biopsies were obtained at 6 hours. In group III, the flap was elevated, the distal 4 X 3 cm was amputated and replaced as a full-thickness skin graft, and biopsies were obtained at 6 hours. In group IV, the flap was elevated, and biopsies were obtained at 12 hours. In group V, the flap was treated as in group III, and biopsies were obtained at 12 hours. In group VI, the flap was elevated, and biopsies were obtained at 24 hours. In group VII, the flap was treated as in group III, and biopsies were obtained at 24 hours. Results: Xanthine oxidase was significantly higher in all distal biopsies compared to proximal biopsies. Xanthine oxidase also increased with time. Malonyldialdehyde increased over time as well as with distance from the flap base. Distal flap biopsies at 24 hours had greatly increased levels of malonyldialdehyde compared to skin grafts (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
C Beas-Zárate A R del Angel Meza A Morales-Villagran A Feria Velasco 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1988,89(2):173-177
1. Endogenous serotonin (5-HT), 5-hydroxyindol acetic acid (5-HIAA) content and exogenous 5-HT uptake (Km and Vmax) were measured in different brain regions (cerebellum, diencephalon, brain stem and telencephalon) of rats fed with a corn diet and restricted protein (8%) diet during 6 weeks. 2. A reduction of 5-HT levels was found in all regions studied of animals fed a corn diet, whereas, 5-HIAA was only decreased in brain stem and diencephalon. 3. An important increase in Km and Vmax were registered in brain stem and diencephalon of protein restricted animals, whereas, an increase of 5-HT uptake affinity in cerebellum, brain stem and telencephalon (35, 42 and 33% respectively) was observed. Simultaneously, under corn diet conditions, the Vmax decreased 40, 30 and 34% respectively in those regions. 4. It is suggested that the brain stem was the more sensitive area under nutritional restricted conditions and the development of some possible compensatory mechanisms of the 5-HTergic system is discussed. 相似文献
7.
Isolated metastatic malignant melanoma to the facial nerve has never been reported. This presentation illustrates a primary melanoma of the helix of the ear that was treated by excisional biopsy and then wedge resection in 1983. The primary melanoma was Clark's level IV and 1.3 mm in thickness. In 1985, a facial paresis slowly developed. There was no gross evidence of recurrent melanoma in the ear or neck, but CT scan showed a mass in the region of the stylo mastoid foramen. A reoperation of the primary site revealed metastatic melanoma in the facial nerve, expanding it to approximately 10 times its normal size. A composite resection was done for the melanoma, and the paralyzed face was immediately rehabilitated by a masseter muscle transfer. The patient received 6000 rads to this area postoperatively and has remained free of disease to date, having returned to his profession as a dentist. A detailed study of all the specimens indicated that this represented a primary metastasis to the facial nerve. 相似文献
8.
Ramón F. Pinilla Amparo Cano Luis Boto Angel Pestan˜a 《Biochemical and biophysical research communications》1984,119(3):1141-1146
A transitory increase in ornithine decarboxylase activity has been observed soon after food removal from Dictyostelium discoideum amoeba. This increase can be prevented by supplementation of the differentiation buffer with the 11 amino acids known for their ability to retard the development of this slime mold. Lysine can replace the amino acid mixture with an apparent inhibition constant of 50 micromolar. This inhibition by lysine, which was only observed in vivo, took place within 5 min and was readily reversed upon lysine removal. 相似文献
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Microbial metabolism of chlorosalicylates: effect of prolonged subcultivation on constructed strains
Miguel Angel Rubio Karl-Heinrich Engesser Hans-Joachim Knackmuss 《Archives of microbiology》1986,145(2):123-125
The hybrid strain Pseudomonas sp. WR4016 was subcultivated with increasing concentrations of 5-chlorosalicylate (510 mM) as sole carbon source over a period of 9 months. At intervals of approximately 3 months derivative strains WR4017, WR4018 and WR4019 were isolated which exhibited higher growth rates and increased substrate tolerance. Comparative analysis of the turnover rates of the key enzymes in chlorosalicylate degradation showed that the adaptation process did not result from structural modifications of these proteins. Instead, balanced over-production of the salicylate hydroxylase and catechol 1,2-dioxygenase prevented the accumulation of toxic chlorocatechols and accounted for the reduction of the doubling times with 4- or 5-chlorosalicylate. A comparative analysis of a genetically engineered chlorosalicylate degrader PL300-1 showed similar regulatory patterns as the most advanced isolate WR4019 from the adaptation series. 相似文献