996 resultados para CONTINUOUS-CULTURE
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The effects of the addition to sausage mix of tocopherols (200 mg/kg), a conventional starter culture with or without Staphylococcus carnosus, celery concentrate (CP) (0.23% and 0.46%), and two doses of nitrate (70 and 140 mg/kg expressed as NaNO(3)) on residual nitrate and nitrite amounts, instrumental CIE Lab color, tocol content, oxidative stability, and overall acceptability were studied in fermented dry-cured sausages after ripening and after storage. Nitrate doses were provided by nitrate-rich CP or a chemical grade source. The lower dose complies with the EU requirements governing the maximum for ingoing amounts in organic meat products. Tocopherol addition protected against oxidation, whereas the nitrate dose, nitrate source, or starter culture had little influence on secondary oxidation values. The residual nitrate and nitrite amounts found in the sausages with the lower nitrate dose were within EU-permitted limits for organic meat products and residual nitrate can be further reduced by the presence of the S. carnosus culture. Color measurements were not affected by the CP dose. Product consumer acceptability was not affected negatively by any of the factors studied. As the two nitrate sources behaved similarly for the parameters studied, CP is a useful alternative to chemical ingredients for organic dry-cured sausage production.
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The objective of this work was to evaluate the addition of Bacillus subtilis probiotic to the feed of common snook (Centropomus undecimalis) fingerlings, in alternate and continuous regimens. Six hundred and sixty fish, with average length of 5.90±0.88 cm and weight of 1.92±0.28 g, were stocked in 12 cages of 1.0 m3, with 55 fish each. The experimental design was completely randomized, with three treatments and four replicates. The treatments consisted of diet with the addition of probiotic, provided in alternate regimen for 7 days and in continuous regimen; besides a control without probiotic in the feed. Zootechnical performance, body composition, immune response, and blood parameters were evaluated. No significant differences were observed in zootechnical performance indexes and in body composition of fish treated with probiotic, when compared to the control. Fish from the alternate regimen showed an increment in respiratory burst and a lower total erythrocyte count than fish from the continuous regimen and the control. Fish from the continuous regimen did not differ from those of the control. The addition of Bacillus subtilis does not increase growth rates of common snook fingerlings; however, it has an immunostimulant action when supplied in alternate regimen.
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Temps de parole: 30 minutes
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OBJECTIVES: To determine whether valganciclovir 450 mg every 48 h for cytomegalovirus (CMV) prophylaxis provides appropriate ganciclovir exposure in solid organ transplant recipients during continuous renal replacement therapy (CRRT). PATIENTS AND METHODS: Ganciclovir pharmacokinetics was intensively studied in two lung transplant recipients under valganciclovir 450 mg every 48 h over one dosing interval. In vitro experiments using blank whole blood spiked with ganciclovir further investigated exchanges between plasma and erythrocytes. RESULTS: Ganciclovir disposition was characterized by apparent total body clearance of 3.3 and 5.8 L/h, terminal half-life of 16.9 and 14.1 h, and apparent volume of distribution of 60.3 and 104.9 L in Patients 1 and 2, respectively. The observed sieving coefficient was 1.05 and 0.96, and the haemofiltration clearance was 3.3 and 3.1 L/h. In vitro experiments confirmed rapid efflux of ganciclovir from red blood cells into plasma, increasing the apparent efficacy of haemofiltration. CONCLUSIONS: A valganciclovir dosage of 450 mg every 48 h appears adequate for patients under CRRT requiring prophylaxis for CMV infection, providing concentration levels in the range reported for 900 mg once daily dosing outside renal failure.
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Tämän tutkimuksen tavoitteena oli selvittää, vaikuttaako kansainvälisen opiskelijan kulttuuritausta opiskelijan odotetun ja koetun yliopistoimagon muodostumiseen. Jotta kulttuurin vaikutuksia yliopistoimagoon voitiin tutkia, tutkimuksessa tunnistettiin yliopistoimagon muodostumiseen oleellisesti vaikuttavat tekijät. Kulttuurin roolia organisaation imagon muodostumisessa ei ole tutkittu aiemmissa tieteellisissä julkaisuissa. Näin ollen tämän tutkimuksen voidaan katsoa edistäneen nykyistä imagotutkimusta. Tutkimuksen kohdeyliopistona oli Lappeenrannan teknillinen yliopisto (LTY). Tutkimuksen empiirinen osa toteutettiin kvantitatiivisena Internet - pohjaisena kyselytutkimuksena tilastollisen analyysin menetelmin. Otos (N=179) koostui kaikista Lappeenrannan teknillisessä yliopistossa lukuvuonna 2005-2006 opiskelleista kansainvälisistä opiskelijoista. Kyselyyn vastasi 68,7 % opiskelijoista. Johtopäätöksenä voidaan todeta, että kulttuurilla ei ole merkittävää vaikutusta yliopistoimagon muodostumiseen. Tutkimuksessa saatiin selville, että yliopiston Internet-sivujen laatu vaikuttaa positiivisesti odotetun yliopistoimagon muodostumiseen, kun taas koettuun yliopistoimagoon vaikuttavat positiivisesti odotettu yliopistoimago, pedagoginen laatu sekä opetusympäristö. Markkinoinnin näkökulmasta tulokset voidaan vetää yhteen toteamalla, että yliopistojen ei tarvitsisi räätälöidä tutkimuksessa tunnistettuja imagoon vaikuttavia tekijöitä eri kulttuureistatulevia opiskelijoita varten.
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Purpose: Mediums have been developed to conserve corneal endothelium in organ-culture during eye banking. CorneaMax® is used by 25% of Eye Bank in Europe. Only little is known about conservation of corneal epithelium with this medium during banking. Its preservation could be of interest in clinic to cure corneal disease with stem cells deficiency. Therefore, we wanted to examine the integrity of human corneal epithelium maintained in CorneaMax®. Methods: Human corneas, considered unsuitable for transplantation, were obtained from the Eye Bank in Lausanne. Average post-mortem time was 14 hours. Cornoscleral rings were maintained in organ-culture in Corneamax® at 32°C. Samples were formalin-fixed after period ranging from 0 (D0) to 35 days (D35, N=5 for each time points) and stained with H&E. Proliferation and apoptosis were evaluated by immunostaining with antibody against Ki67 and Caspase3 respectively. Results: Corneas, which were not in organ-cultured (D0), showed different morphology, including intact epithelium with 5 to 7 layers, but also completely denuded basement membrane. In two cases, at D0, the epithelium lost its adherence to the basal lamina of the cornea creating a large epithelial sheet. During the two first days, corneas and limbus area lost totally their epithelium, except for some remaining limbal basal cells. From day 2 to day 10, regeneration of the epithelium took place, starting from the limbal region in direction to the central cornea. From day 10 to day 35, corneal epithelium appeared as an atrophic epithelium, consisting of only two cell layers. Proliferation happened in the whole cornea during the 35 days of organ-culture, as shown by Ki67 positive cells. Apoptosis was rarely detected in the corneal epithelium. Conclusions: Corneas maintained in CorneaMax® showed a complete disappearance of the corneal epithelium during the two first days and a conservation of limbal basal cells in the limbal region. These remaining cells allowed a full regeneration of the tissue, leading to an atrophic epithelium, composed of only two cell layers. This atrophic epithelium could be seen in all the organ-cultured corneas during the 35 days of conservation. This study is a first step to develop medium in organ-culture in order to conserve corneal epithelial cells.
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Heretofore the issue of quality in forensic science is approached through a quality management policy whose tenets are ruled by market forces. Despite some obvious advantages of standardization of methods allowing interlaboratory comparisons and implementation of databases, this approach suffers from a serious lack of consideration for forensic science as a science. A critical study of its principles and foundations, which constitutes its culture, enables to consider the matter of scientific quality through a new dimension. A better understanding of what pertains to forensic science ensures a better application and improves elementary actions within the investigative and intelligence processes as well as the judicial process. This leads to focus the attention on the core of the subject matter: the physical remnants of the criminal activity, namely, the traces that produce information in understanding this activity. Adapting practices to the detection and recognition of relevant traces relies on the apprehension of the processes underlying forensic science tenets (Locard, Kirk, relevancy issue) and a structured management of circumstantial information (directindirect information). This is influenced by forensic science education and training. However, the lack of homogeneity with regard to the scientific nature and culture of the discipline within forensic science practitioners and partners represents a real challenge. A sound and critical reconsideration of the forensic science practitioner's roles (investigator, evaluator, intelligence provider) and objectives (prevention, strategies, evidence provider) within the criminal justice system is a means to strengthen the understanding and the application of forensic science. Indeed, the whole philosophy is aimed at ensuring a high degree of excellence, namely, a dedicated scientific quality.
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Continuous positive airway pressure, aimed at preventing pulmonary atelectasis, has been used for decades to reduce lung injury in critically ill patients. In neonatal practice, it is increasingly used worldwide as a primary form of respiratory support due to its low cost and because it reduces the need for endotracheal intubation and conventional mechanical ventilation. We studied the anesthetized in vivo rat and determined the optimal circuit design for delivery of continuous positive airway pressure. We investigated the effects of continuous positive airway pressure following lipopolysaccharide administration in the anesthetized rat. Whereas neither continuous positive airway pressure nor lipopolysaccharide alone caused lung injury, continuous positive airway pressure applied following intravenous lipopolysaccharide resulted in increased microvascular permeability, elevated cytokine protein and mRNA production, and impaired static compliance. A dose-response relationship was demonstrated whereby higher levels of continuous positive airway pressure (up to 6 cmH(2)O) caused greater lung injury. Lung injury was attenuated by pretreatment with dexamethasone. These data demonstrate that despite optimal circuit design, continuous positive airway pressure causes significant lung injury (proportional to the airway pressure) in the setting of circulating lipopolysaccharide. Although we would currently avoid direct extrapolation of these findings to clinical practice, we believe that in the context of increasing clinical use, these data are grounds for concern and warrant further investigation.
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Spondias mombin L. shoot cultures were initiated from nodal explants taken from plants propagated by seeds. Explants coming from 4-6 months old plants, previously disinfected, were cultivated on WPM medium supplemented with a wide range of concentrations of BAP (0.0, 0.22, 0.44, 2.22 and 4.44 muM) and NAA (0.0, 0.27 and 2.70 muM). After four weeks, the responses obtained were axillary shoot and root formation. The first response were preferentially induced with the medium containing only BAP, regardless of the BAP concentration. The addition of NAA on medium reduced significantly axillary shoot formation and induced rhizogenesis. Roots were formed on nodal explant basis, preferentially on medium supplemented with 4.44 muM NAA. The medium supplemented with BAP reduced significantly root formation.
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Objective: Respiratory assistance with nasal continuous positive airway pressure (n-CPAP) is an effective treatment in premature newborns presenting respiratory distress. The aim of the study was to depict cardiac function, systemic (Qs) and pulmonary output (Qp) by echocardiography in stable premature infants requiring prolonged n-CPAP. Our hypothesis was that n-CPAP could reduce pulmonary blood flow. Patients and methods: All premature infants < 32 weeks gestation, > 7 days-old, requiring n-CPAP without severe respiratory compromise nor need for additional oxygen were prospectively included. Every patient had a first echocardiography while on n-CPAP. N-CPAP was then discontinued for two hours and a second echocardiography was performed. Results: 17 premature infants were included. Mean gestational age was 28 ± 2 weeks and mean weight 1.1 ± 0.3 kg. Following retrieval of n-CPAP we observed an increase in Qp of 53 ml/kg/min (95% CI 19-87 ml/kg/min), but no significant change in Qs. Consecutively a significant increase in Qp/Qs ratio of 16% was found (95% CI 7-29%). Conclusions: Nasal continuous positive airway pressure has hemodynamic effects in preterm infants in stable pulmonary and cardiac conditions. It reduces pulmonary output without interference with systemic output.
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Abstract: The canine distemper virus A75/17 wild-type strain, which is unable to replicate in cell lines, was adapted to growth in Vero cells. Sequence comparison between the A75/17 and the Vero cell-adapted A75/17-V virus revealed 7 amino acid differences between the 2 viruses. Three of these were located in the matrix protein, three in the phosphoprotein also changing the V protein but not the C protein and one in the large protein. The phosphoprotein and the large protein constituted the viral RNA polymerase whose activity was studied by transfection experiments using a reverse genetic system with a plasmid encoding a minireplicon and expression plasmids encoding the nucleocapsid protein and the viral RNA polymerase subunits. Surprinsingly, the enzyme of A75/17 CDV was significantly more active in cell lines compared to the polymerase of A75/17-V CDV. The decrease in overall enzyme activity was found to be due to both decreased replication and transcription activity. This polymerase attenuation was confirmed in CHO cells infection stably expressing the dog SLAM receptor mainly found in dog's lymphoid organs and allowing both virus strains to enter these cells at the same efficiency. A75/17-V CDV replicated more slowly in CHODogSLAM cells than A75/17 CDV and syncytium formation was significantly decreased compared to A75/17 infected CHODogSLAM cells.. Cell culture adaptation lead to an attenuated virus strain both in vitro and in vivo with decreased polymerase activity and syncytium forming capability showing an important role of the polymerase in determining the phenoytpe of the virus. In addition, this reduced phenotype of A75/17-V CDV was shown to be due to the P mutations in the P protein only, showing an important function of the polycistronic P gene in the adaptation process. The role of the matrix protein was found not to have any effect on polymerase activity, however its participation in the adaptation process still needs to be elucidated. The accessory proteins V and C were shown to act on polymerase activity, but their functions in virus pathogenicity and in inhibiting the interferon system have not been studied in this thesis. The V proteins have an activating effect on the polymerase of both the A75/17 and the A75/17-V CDV strains. Although the C protein amino acid sequence was not changed during adaptation of wild-type canine distemper virus in Vero cells, the C protein was demonstrated to have opposite effects on polymerase activity of both virus strains suggesting a different interaction of the C protein with the proteins forming the polymerase complex, which could modulate polymeras activity. These effects were demonstrated by transfection experiments and studying recombinant viruses not expressing the C protein. Thus, the abrogation of the C protein decrease the activity of the wild-type polymerase. In contrast, the polymerase activity of the Vero cell- adapted virus is enhanced in the absence of the C protein and this has also been demonstrated with a recombinant virus, which grew faster in the first 48 hours of infection. Future studies will focus on the generation of recombinant wild-type viruses, which should be very helpful in understanding the molecular mechanisms underlying the adaptation process and the loss of pathogenicity.