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Notes: Protein modification by ADP-ribose polymers is a common regulatory mechanism in eukaryotic cells and is involved in several aspects of brain physiology and physiopathology, including neurotransmission, memory formation, neurotoxicity, ageing and age-associated diseases. Here we show age-related misregulation of poly(ADP-ribose) synthesis in rat cerebellum as revealed by: (i) reduced poly(ADP-ribose) polymerase-1 (PARP-1) activation in response to enzymatic DNA cleavage, (ii) altered protein poly(ADP-ribosyl)ation profiles in isolated nuclei, and (iii) cell type-specific loss of poly(ADP-ribosyl)ation capacity in granule cell layer and Purkinje cells in vivo. In particular, although PARP-1 could be detected in virtually all granule cells, only a fraction of them appeared to be actively engaged in poly(ADP-ribose) synthesis and this fraction was reduced in old rat cerebellum. NAD+, quantified in tissue homogenates, was essentially the same in the cerebellum of young and old rats suggesting that in vivo factors other than PARP-1 content and/or NAD+ levels may be responsible for the age-associated lowering of poly(ADP-ribose) synthesis. Moreover, PARP-1 expression was substantially down-regulated in Purkinje cells of senescent rats.

Notes: Infection by any of the four serotypes of dengue viruses (DEN-1, -2, -3 and -4) may result in either a relatively benign fever, called dengue fever (DF), a fatal disease, such as dengue haemorrhagic fever (DHF) or dengue shock syndrome (DSS). Several lines of evidence suggest that soluble immune response mediators may be involved in the severity of dengue infections. For instance, elevated seric levels of IL-8 are a common feature in DHF patients. Because other chemokines, cytokines, adhesion molecules, chemokine and cytokine receptors, as well as cytokine-related molecules may also be involved in dengue virus pathogenesis, we aimed at analysing the gene expression of such molecules in the course of an in vitro DEN-2 infection of human peripheral blood monocyte-derived macrophages, a cell type regarded as a primary target for DEN. Nylon membrane gene arrays containing 375 different human cytokine-related genes were used as a first step to search for differentially expressed genes upon infection. Transcripts for IL-8, IL-1β, osteopontin, GRO-α, -β and -γ, I-309, and some other molecules showed to be upregulated upon infection, whereas others such as MIC-1, CD27L and CD30L, were downregulated. Four genes were selected for reverse transcriptase-polymerase chain reaction based gene-expression analysis as a way to partially confirm microarray results. This approach pointed out 25 macrophage-expressed cytokine-related genes that could be relevant in DEN-2 pathogenesis.

Notes: Possible mechanism(s) of resistance to auxinic herbicides in wild mustard (Sinapis arvensis L.) were investigated by characterizing responses of susceptible and resistant biotypes to 2,4-D, di-camba or picloram. No differences between bio-types were observed in absorption, translocation, or metabolism of foliar-applied radiolabelled herbicides. In contrast, the levels of ethylene production varied between biotypes. The susceptible biotype produced twofold and sixfold more ethylene than the resistant biotype within 4 h and 44 h of herbicide application, respectively. These results suggest that the mechanism of resistance in wild mustard is not due to differences in absorption, translocation, or metabolism. Ethylene production studies imply that resistance to auxinic herbicides may be attributed to altered target site(s) of action. Bases physiologiques de la résistance aux herbicides auxiniques d'un biotype de moutarde des champs (Sinapis arvensis L.)Les mécanismes possibles de la résistance aux herbicides auxiniques chez la moutarde des champs (Sinapis arvensis L.) ont été recherchés en caractérisant les réponses de biotypes résis-tants et sensibles au 2,4-D, au dicamba et au pi-clorame. Aprés application des herbicides radioactifs sur le feuillage, aucune différence d'absorption, de migration ou de métabolisme n'a été observée. Par contre, la production d'éthylene différait entre les biotypes. Le biotype sensible produisait 2 et 6 fois plus d'éthylène que le biotype sensible, respectivement 4 et 44 heures après l'application d'herbicide. Ces résultats sug-gèrent que la résistance aux herbicides auxiniques chez la moutarde des champs n'est pas due à des différences d'absorption, de migration ou de métabolisme mais pourrait provenir d'une altération du site d'action.Physiologische Untersuchung der Resistenz eines Acker-Senf-(Sinapis arvensis-) Biotyps gegenüber WuchsstoffherbizidenDer mögliche Mechanismus der Resistenz gegenüber Wuchsstoffherbiziden beim Acker-Senf (Sinapis arvensis L.) wurde unhand der Reaktion von empfindlichen und resistenten Biotypen gegenüber 2,4-D, Dicamba oder Picloram untersucht. Hinsichtlich Absorption, Translokation oder Metabolismus der auf die Blätter applizierten, radioaktiv markierten Her-bizide wurden keine Unterschiede beobachtet. Die Ethylenbildung variierte jedoch zwischen den Biotypen. Der empfindliche produzierte in-nerhalb 4 oder 44 Stunden nach der Herbizid-applikation 2-bzw. 6mal mehr Ethylen als der resistente. Aus den Ergebnissen läßt sich schließen, daß beim Acker-Senf der Resisten-zmechanismus nicht in der Absorption, der Translokation oder dem Metabolismus liegt, sondern die Ethylenbildung daran beteiligt ist, wo die Wirkorte fur die Wuchsstoffherbizide liegen.

Notes: Helicobacter pylori has attracted increasing attention among gastroenterologists because of its pathogenic potential, stimulating the search for non-invasive diagnostic tests.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:In this study the efficacy of a new enzyme immunoassay designed to detect H. pylori antigens in stools (HpSA) was evaluated before and after eradication therapy.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:HpSA was performed on stool samples collected from 268 patients whose H. pylori status was defined on the basis of concordant results for the 13C-urea breath test, rapid urease test and histology. The H. pylori-positive patients were treated with a 1-week triple therapy to eradicate the infection. One (T30) and 3 months (T90) after the end of therapy, 13C-urea breath test and HpSA were repeated in the treated patients.〈section xml:id="abs1-4"〉〈title type="main"〉Results:The overall diagnostic accuracy of HpSA at T30 (83%, 95% confidence interval (CI) 77–89%) was significantly lower in comparison to the values obtained at baseline (94%, 95% CI: 91–97%) and at T90 (97%, 95% CI: 94–99%). No significant difference was found between the diagnostic accuracy of HpSA at baseline and at T90 (P=0.253).〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:The present data suggest that HpSA provides a low diagnostic accuracy when used shortly after treatment. It needs a longer period of follow-up (8–12 weeks) to reach a reliability comparable to the 13C-urea breath test.

Notes: Abstract It is shown that the Partially Overlapping Molecular Level Model (POMLM) accounts for the experimental results of the dissipative28Si +48Ti collision around 210 MeV incident energy. The general trend of the properties of the fluctuations as well as the average angular distributions are reproduced by the same set of main parameters. A general consistency is also found between the present data and the data obtained in previous work on the same colliding system performed at lower incident energy (around 123 MeV).

Notes: Summary It is well-known that periodic solutions of semilinear wave equations can be obtained as critical points of related functionals. In the situation that we studied, there is usually an obvious solution obtained as a solution of linear problem. We formulate a dual variational problem in such a way that the obvious solution is a local minimum. We then find additional non-obvious solutions via a numerical mountain pass algorithm, based on the theorems of Ambrosetti, Rabinowitz and Ekeland. Numerical results are presented.

Notes: Abstract The pulmonary inflammatory response to NO2 exposure was measured by evaluating a series of biochemical and cellular parameters in rat bronchoalveolar lavage fluid. Animals were exposed to 9 mg/m3 (5 ppm) or 18 mg/m3 (10 ppm) of the gas for 24 h or 7 days. After bronchoalveolar lavage collection, a differential count of polymorphonuclear leukocytes, macrophages, and lymphocytes was done. A significant increase in polymorphonuclear leukocytes was found after 24 h of exposure, and after 7 days the number of macrophages increased significantly. After 7 days of exposure to 9 mg/m3 of NO2 (a dose that under our conditions did not induce migration of cells in the bronchoalveolar spaces) the ex vivo phorbol myristate acetate-induced superoxide anion production by resident cells was inhibited. After 24 h and 7 days of exposure to 18 mg/m3 of NO2, phorbol myristate acetate-induced superoxide anion production was lower than in the control group. The migration of polymorphonuclear leukocytes in the bronchoalveolar lavage fluid was not associated with any real increase in elastase. However, there was a dose- and time-dependent increase in α1-proteinase inhibitor in response to both 9 and 18 mg/m3 of NO2. Total glutathione was significantly increased in blood by 24 h treatment with 9 or 18 mg/m3 of NO2, whereas blood oxidized glutathione was not affected. In lung tissue we observed only a significant increase of oxidized glutathione after 24 h of exposure to 9 and 18 mg/m3 of NO2. These data suggest that many biochemical and cellular parameters are altered after acute or subacute exposure to relatively high doses of NO2, especially in the first 24 h. The increase of α1-proteinase inhibitor and blood glutathione can be considered a prompt protective response to the toxic injury.

Notes: Abstract Vascular complications remain a significant nonimmunologic source of pancreas allograft loss. From February 1993 through January 1998, we performed 98 simultaneous pancreas-kidney transplantations (SPK) using pancreatic exocrine bladder drainage in patients with type 1 insulin-dependent diabetes mellitus and end-stage renal disease. They originally received quadruple immunosuppression, and since May 1997 triple immunosuppression protocol (tacrolimus, mycophenolate mofetil, and steroids). The patients' mean age was 37 years (range 24–53 years), including 50 women and 48 men with a mean follow-up of 42 months. The overall rate of vascular complications was 6 % (5 patients). The vascular complications were as follows: late thrombosis of the Y with persistent pancreas allograft function (n = 1), rupture of a pseudoaneurysm of the superior mesenteric artery (PSMA) with an arteriovenous fistula (AVF) (n = 1), thrombosis of the splenic vein (SV) (n = 3), complete thrombosis of the superior mesenteric vein (SMV) and splenic vein (n = 1). The patient with PSMA underwent surgical correction of the AVF and PSMA with preservation of the allograft pancreas function. The other patient with late thrombosis of the Y-graft required no treatment. All 3 patients with SV thrombosis were systemically heparinized followed by oral anticoagulation. The patient with complete thrombosis required surgical thrombectomy of the SMV and SV followed by heparinization and oral anticoagulation. All 6 patients including the 4 with thrombosis had preservation of the pancreas function. Serial pancreas ultrasound showed resolution and improvement with recanalization of the splenic vein and superior mesenteric vein in those patients with thrombosis. We describe our vascular experience with salvage of the pancreatic allograft function. Surgery seems to be the best treatment option in the case of AVF or complete thrombosis of the allograft. Intravenous heparin followed by oral anticoagultion could be a conservative approach for SV thrombosis.

Notes: Summary One of the earliest biochemical effects induced by the herbicide paraquat (PQ) is damage to type II pneumocytes with consequent depletion of surfactant (Skillrud and Martin, 1984). We made a series of studies on the possible protective effect of drug ambroxol, which induces surfactant synthesis from alveolar type II cells (Post et al. 1983). The cell line A-549, exposedin vitro to PQ concentrations ranging from 0.5×10-4 to 2×10-3 M, showed a significant dose-dependent loss of viability. Ambroxol (10 mg/ml) pretreated cells were more resistant to PQ, their viability starting to decrease from a PQ concentration of 0.8×10-3 M. Membrane microviscosity was measured on the same cells. Cells treated with PQ alone showed a reduction of membrane microviscosity which was significantly counteracted by ambroxol pretreatment. The curves for membrane microviscosity of PQ and ambroxol-plus-PQ-treated cells overlapped those for cell viability, indicating that the stimulation of surfactant synthesisin vitro may be a prerequisite for counteracting some of the precocious effects of PQ. Partial protection from PQ- induced mortality was also obtainedin vivo.

Notes: Summary It is still controversial whether the familial environment plays a role in the diffusion of HCV infection. The aim of this study was to evaluate the prevalence of anti-HCV positivity in the household contacts of patients with HCV-related chronic hepatitis. Nearly all the household contacts of 113 subjects with anti-HCV+ chronic hepatitis (100/113 spouses and 260/290 children) were investigated. Anti-HCV was determined by means of ELISA II and was confirmed by RIBA II. Anti-HCV positivity was found in 27% of the spouses and in 1.9% of the children. Prevalence of anti-HCV positivity in spouses correlated positively with the duration of the marital status. Seventeen/32 (53.1%) of anti-HCV-positive subjects were found to have chronic hepatitis. This study indicates that intrafamilial diffusion of HCV infection is mostly accounted for by horizontal, in particular spouse to spouse, transmission and that spouse to spouse transmission of HCV infection correlates positively with the duration of marital status.