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11.
This study is the largest Italian survey on liver retransplantations (RET). Data report on 167 adult patients who received 2 grafts, 16 who received 3 grafts, and one who received 4 grafts over a 11 yr period.There was no statistically significant difference in graft survival after the first or the second RET (52, 40, and 29% vs 44, 36, and 18% at 1,5,and 10 yr, respectively: Log-Rank test, p = 0.30).Survivals at 1, 5, and 10 years of patients who underwent 2 (n = 151) or 3 (n = 15) RETs, were 65, 48,and 39% vs 59, 44, and 30%, respectively (p = 0.59).Multivariate analysis of survival showed that only the type of graft (whole vs reduced) was associated with a statistically significant difference (HR = 3.77, Wald test p = 0. 05); the donor age appeared to be a relevant factor as well, although the difference was not statistically significant (HR = 1.91, Wald test p = 0.08).Though late RETs have better results on long term survival relative to early RETs, no statistically significant difference can be found in early results, till three years after RET.Considering late first RETs (interval>30 days from previous transplantation) with whole grafts the difference in graft survival in RETs due to HCV recurrence (n = 17) was not significantly different from RETs due to other causes (n = 53) (65–58 and 31% vs 66–57 and 28% respectively at 1–5 and 10 years, p = 0.66).  相似文献   
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Coral Reefs - Fire corals of the hydrocoral genus Millepora provide an important ecological role as framework builders of coral reefs in the Indo-Pacific and the Atlantic. Recent works have...  相似文献   
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This work aims to elucidate the mechanisms involved in the early activation of glucose transport in hematopoietic M07e cells by stem cell factor (SCF) and a reactive oxygen species (ROS) as H2O2. SCF and H2O2 increase Vmax for glucose transport; this enhancement is due to a higher content in GLUT1 in plasma membranes, possibly through a translocation from intracellular stores. Inhibitors of tyrosine kinases or phospholipase C (PLC) remove glucose transport enhancement and prevent translocation. The inhibitory effect of STI-571 suggests a role for c-kit tyrosine kinase on glucose transport activation not only by SCF, but also by H2O2. On the other hand, neither protein kinase C nor phosphoinositide-3-kinase appear to be involved in the acute activation of glucose transport. Our data suggest that i) in M07e cells, SCF and exogenous H2O2 elicit a short-term activation of glucose transport through a translocation of GLUT1 from intracellular stores to plasma membranes; ii) both stimuli could share at least some signaling pathways leading to glucose uptake activation, involving protein tyrosine kinases and PLC iii) H2O2 could act increasing the level of tyrosine phosphorylation through the inhibition of tyrosine phosphatases and mimicking the regulation role of endogenous ROS.  相似文献   
14.
The bulbocavernosus (BC) and levator ani (LA) muscles are present in males but absent or severely reduced in females, and the fate of these muscles controls the survival of motoneurons in the sexually dimorphic spinal nucleus of the bulbocavernosus. However, the mechanism underlying the sex difference in BC and LA development has been controversial. We examined the role of cell death in sexual differentiation of the bulbocavernosus BC/LA muscles in mice. Muscle development was mapped from embryonic day 16 (E16) to postnatal day 5 (P5). A sex difference (male>female) first arose on E17 (BC) or E18 (LA), and increased in magnitude postnatally. TUNEL labeling revealed dying cells in the BC and LA muscles of both sexes perinatally. However, females had a significantly higher density of TUNEL-positive cells than did males. A role for the proapoptotic factors, Bax and Bak, in BC/LA development was tested by examining mice lacking one or both of these proteins. In females lacking either Bax or Bak, the BC was absent and the LA rudimentary. Deletion of both bax and bak genes, however, rescued the BC, increased LA size approximately 20-fold relative to controls, and virtually eliminated TUNEL-positive cells in both muscles. We conclude that cell death plays an essential role in sexual differentiation of the BC/LA muscles. The presence of either Bax or Bak is sufficient for cell death in the BC/LA, whereas the absence of both prevents sexually dimorphic muscle cell death.  相似文献   
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Volatile compounds produced by adults of Anchomenus dorsalis under undisturbed and disturbed conditions were investigated with an all-glass aeration apparatus. GC-MS analysis of the crude extracts from undisturbed and disturbed adults highlighted four major volatile compounds, undecane, heneicosane, Z-9 tricosene and tricosane, of which significantly more undecane was released by disturbed adults compared to undisturbed beetles. The pygidial glands of adults of Anchomenus dorsalis were investigated using light and Transmission Electron Microscopy (TEM). Each gland showed dense aggregates of secretory cells organized into visually distinct lobes; a long collecting canal that drains the secretion towards the reservoir, a bean-shaped double lobed muscular reservoir in which secretion is stored and a short duct (efferent duct) through which the secretion is discharged. The function of the pygidial glands and the possible role played by undecane as a defensive allomone and/or chemical signalling molecule are discussed.  相似文献   
17.
The sarcosaprophagous fauna plays a key role in organic matter decomposition. Moreover, the biological, ecological and behavioral specificities of the taxa are useful to reconstruct the decay history of a corpse or carcass, often back to the lethal event. Here we report the seasonal succession of the insect fauna on a pig carcass exposed in a rural area in Calabria (southern Italy) during summer 2007 and 2008. The aim is to identify and qualitatively assess the major taxa of forensic importance in this region. The principal fly invaders were Lucilia caesar (L.), L. sericata (Meigen, 1826), Chrysomya albiceps (Wiedemann, 1819), Sarcophaga (Meigen, 1826) spp. and Amobia (Robineau‐Desvoidy, 1830) spp., Musca domestica (L.) and Muscina stabulans (Fallen, 1817). The primary beetle species collected in summer belonged to Dermestidae, Dermestes maculatus (De Geer, 1774) and Cleridae, Necrobia rufipes (De Geer, 1775). This paper also examined the ecological role of ants in the insect succession and describes the evidence of skin injuries directly inflicted by the acrobat ant Crematogaster (Acrocoelia) scutellaris (Olivier, 1791) (Hymenoptera Formicidae) while feeding on pig carrion. Ants belonging to two other species were also collected: Camponotus aethiops (Latreille, 1798) and Tetramorium semilaeve (André, 1881). Ants can invade carcasses and corpses directly, disrupting blowfly egg laying or preying on their larvae. Our data on the carrion faunal composition and role of ants as invaders should be useful for further forensic cases in Calabria (southern Italy). This is among the few reports of ants as forensically relevant species.  相似文献   
18.
The design and development of a PNA microarray designed for the simultaneous identification of several SNPs characteristic of seven different tomato varieties is described. Highly selective arginine-based monomer containing PNAs (Arg-PNAs) have been used in order to obtain very selective probes. Seven modified PNA probes were synthesised and their binding properties in solution were studied. PNA-microarrays based on these probes were prepared and applied to SNP discrimination in model experiments using oligonucleotide mixtures simulating the different sequences of the seven tomato varieties. The strength and the limitations of such a system for SNP recognition are thoroughly discussed.  相似文献   
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This study demonstrates that oxidative stress induced in rat thymocytes by the hydrophilic 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), the lipophilic cumene hydroperoxide (CumOOH) and the freely diffusible H2O2 is associated with an activation of facilitative glucose transport rate, mediated by GLUT1, the major transporter in this cell type. We compared the effects of the three tested radical sources on the kinetic transport parameters, showing that the transport rate enhancement in the treated cells can be ascribed to an increase in the Vmax value, apart from the site of generation of the oxidative stress. The enhancement of glucose transport by the three oxidants in thymocytes was significantly attenuated both by protein tyrosine kinase inhibitors as genistein and tyrphostin A23 and by U73122, a phospholipase C inhibitor. Genistein and U73122 reversed also the cited increase of Vmax values. It is concluded that the stimulation of glucose transport in response to different oxidants is mediated, at least in part, through reactive oxygen species (ROS)-induced stimulation of protein tyrosine kinase and phospholipase C pathways.  相似文献   
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