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991.
Aline Machado de Castro Marcelle Lins de Albuquerque de Carvalho Selma Gomes Ferreira Leite Nei Pereira Jr. 《Journal of industrial microbiology & biotechnology》2010,37(2):151-158
The objective of this work is to investigate the utilization of two abundant agricultural residues in Brazil for the production and application of cellulolytic enzymes. Different materials obtained after pretreatment of sugarcane bagasse, as well as pure synthetic substrates, were considered for cellulase production by Penicillium funiculosum. The best results for FPase (354 U L?1) and β-glucosidase (1,835 U L?1) production were observed when sugarcane bagasse partially delignified cellulignin (PDC) was used. The crude extract obtained from PDC fermentation was then partially characterized. Optimal temperatures for cellulase action ranged from 52 to 58°C and pH values of around 4.9 contributed to maximum enzyme activity. At 37°C, the cellulases were highly stable, losing less than 15% of their initial activity after 23 h of incubation. There was no detection of proteases in the P. funiculosum extract, but other hydrolases, such as endoxylanases, were identified (147 U L?1). Finally, when compared to commercial preparations, the cellulolytic complex from P. funiculosum showed more well-balanced amounts of β-glucosidase, endo- and exoglucanase, resulting in the desired performance in the presence of a lignocellulosic material. Cellulases from this filamentous fungus had a higher glucose production rate (470 mg L?1 h?1) when incubated with corn cob than with Celluclast®, GC 220® and Spezyme® (312, 454 and 400 mg L?1 h?1, respectively). 相似文献
992.
An enzymatic biosensor was fabricated by the covalent immobilization of pyruvate oxidase (PyO) onto the nano-particle comprised poly-5,2':5',2'-terthiophene-3'-carboxylic acid, poly-TTCA (nano-CP) layers on a glassy carbon electrode (GCE) for the amperometric detection of the phosphate ions. The direct electron transfer reaction of the immobilized PyO onto the nano-CP layers was investigated and the electron transfer rate constant was determined to be 0.65 s(-1). The electrochemically prepared nano-CP lowered the oxidation potential (+0.40 V versus Ag/AgCl) of an enzymatically generated H(2)O(2) by PyO in a phosphate solution. Experimental parameters affecting the sensitivity of the biosensors, such as amounts of the cofactors, the pH, the applied potential, and the temperature were optimized. A linear response for the detection of the phosphate ion was observed between 1.0 microM and 100 microM and the detection limit was determined to be about 0.3 microM. The response time of the biosensors was about 6s. The biosensor showed good selectivity towards other interfering anions. The long-term storage stability of the phosphate biosensor was studied and the sensor was applied in a human serum sample for the phosphate ions detection. 相似文献
993.
994.
The activation of cholinergic pathways by nicotine elicits various physiological and pharmacological effects in mammals. For example, the stimulation of nicotinic acetylcholine receptors (nAChRs) leads to an antinociceptive effect. However, it remains to be elucidated which subtypes of nAChR are involved in the antinociceptive effect of nicotine on nerve injury-induced allodynia and the underlying cascades of the nAChR-mediated antiallodynic effect. In this study, we attempted to characterize the actions of nicotine at the spinal level against mechanical allodynia in an animal model of neuropathic pain, tibial nerve transection (TNT) in rats. It was found that the intrathecal injection of nicotine, RJR-2403, a selective alpha4beta2 nAChR agonist, and choline, a selective alpha7 nAChR agonist, produced an antinociceptive effect on the TNT-induced allodynia. The actions of nicotine were almost completely suppressed by pretreatment with mecamylamine, a non-selective nicotinic antagonist, or dihydro-beta-erythroidine, a selective alpha4beta2 nAChR antagonist, and partially reversed by pretreatment with methyllycaconitine, a selective alpha7 nAChR antagonist. Furthermore, pretreatment with strychnine, a glycine receptor antagonist, blocked the antinociception induced by nicotine, RJR-2403, and choline. On the other hand, the GABAA antagonist bicuculline did not reverse the antiallodynic effect of nicotine. Together, these results indicate that the alpha4beta2 and alpha7 nAChR system, by enhancing the activities of glycinergic neurons at the spinal level, exerts a suppressive effect on the nociceptive transduction in neuropathic pain. 相似文献
995.
Machado PR Ampuero J Guimarães LH Villasboas L Rocha AT Schriefer A Sousa RS Talhari A Penna G Carvalho EM 《PLoS neglected tropical diseases》2010,4(12):e912
Background
Cutaneous leishmaniasis (CL) is treated with parenteral drugs for decades with decreasing rate cures. Miltefosine is an oral medication with anti-leishmania activity and may increase the cure rates and improve compliance.Methodology/Principal Findings
This study is a randomized, open-label, controlled clinical trial aimed to evaluate the efficacy and safety of miltefosine versus pentavalent antimony (Sbv) in the treatment of patients with CL caused by Leishmania braziliensis in Bahia, Brazil. A total of 90 patients were enrolled in the trial; 60 were assigned to receive miltefosine and 30 to receive Sbv. Six months after treatment, in the intention-to-treat analyses, the definitive cure rate was 53.3% in the Sbv group and 75% in the miltefosine group (difference of 21.7%, 95% CI 0.08% to 42.7%, p = 0.04). Miltefosine was more effective than Sbv in the age group of 13–65 years-old compared to 2–12 years-old group (78.9% versus 45% p = 0.02; 68.2% versus 70% p = 1.0, respectively). The incidence of adverse events was similar in the Sbv and miltefosine groups (76.7% vs. 78.3%). Vomiting (41.7%), nausea (40%), and abdominal pain (23.3%) were significantly more frequent in the miltefosine group while arthralgias (20.7%), mialgias (20.7%) and fever (23.3%) were significantly more frequent in the Sbv group.Conclusions
This study demonstrates that miltefosine therapy is more effective than standard Sbv and safe for the treatment of CL caused by Leishmania braziliensis in Bahia, Brazil.Trial Registration
Clinicaltrials.gov Identifier NCT00600548相似文献996.
Debasish Saha Md. Nahiduzzaman Shirin Akter Mohammad Nazrul Islam Mostafa Ali Reza Hossain Md. Samsul Alam 《Genes & genomics.》2010,32(1):47-53
Microsatellite DNA marker analysis was carried out to assess the population genetic structure of an endangered carp, Labeo calbasu, collected from three different stocks; the Jamuna River, the Halda River and a Hatchery. Four heterologous microsatellite loci (Lr12, Lr14b, Lr21 and Lr24) identified from rohu (Labeo rohita) were analyzed to test the genetic variability of the target kalibaus stocks. The maximum number of alleles observed in loci Lr12, Lr14b, Lr21 and Lr24 were 10, 7, 8 and 6, respectively. The loci were found to be polymorphic (<P 95) in all the populations. The average number of allele was highest in the Jamuna population (6.75) followed by that of the Halda (5.50) and the Hatchery population (4.25). The observed average heterozygosity (Ho) value was almost similar in all three populations. Except locus Lr12 in the Halda population, significant deviations from the Hardy-Weinberg Equilibrium were detected in all cases due to excess heterozygosity. The population differentiation values (F ST ) between all the population pairs were significant. The highest genetic distance value (D = 0.295) was measured between the Halda and the Hatchery populations. A recent bottleneck was observed in the Halda and the Hatchery population. 相似文献
997.
Juliana de Saldanha da Gama Fischer Lujian Liao Paulo C. Carvalho Valmir C. Barbosa Gilberto B. Domont Maria da Gloria da Costa Carvalho John R. Yates 《Journal of Proteomics》2010,73(5):1018-1027
Perillyl alcohol (POH) is a naturally occurring terpene and a promising chemotherapeutic agent for glioblastoma multiform; yet, little is known about its molecular effects. Here we present results of a semi-quantitative proteomic analysis of A172 cells exposed to POH for different time-periods (1′, 10′, 30′, 60′, 4 h, and 24 h). The analysis identified more than 4000 proteins; which were clustered using PatternLab for proteomics and then linked to Ras signaling, tissue homeostasis, induction of apoptosis, metallopeptidase activity, and ubiquitin-protein ligase activity. Our results make available one of the most complete protein repositories for the A172. Moreover, we detected the phosphorylation of GSK3β (Glycogen synthase kinase) and the inhibition of ERK's (extracellular signal regulated kinase) phosphorylation after 10′, which suggests a new mechanism of POH's activation for apoptosis. 相似文献
998.
de Carvalho EC Jayanti MK Batilana AP Kozan AM Rodrigues MJ Shah J Loures MR Patil S Payne P Pietrobon R 《PloS one》2010,5(11):e13893
Background
With the globalization of clinical trials, a growing emphasis has been placed on the standardization of the workflow in order to ensure the reproducibility and reliability of the overall trial. Despite the importance of workflow evaluation, to our knowledge no previous studies have attempted to adapt existing modeling languages to standardize the representation of clinical trials. Unified Modeling Language (UML) is a computational language that can be used to model operational workflow, and a UML profile can be developed to standardize UML models within a given domain. This paper''s objective is to develop a UML profile to extend the UML Activity Diagram schema into the clinical trials domain, defining a standard representation for clinical trial workflow diagrams in UML.Methods
Two Brazilian clinical trial sites in rheumatology and oncology were examined to model their workflow and collect time-motion data. UML modeling was conducted in Eclipse, and a UML profile was developed to incorporate information used in discrete event simulation software.Results
Ethnographic observation revealed bottlenecks in workflow: these included tasks requiring full commitment of CRCs, transferring notes from paper to computers, deviations from standard operating procedures, and conflicts between different IT systems. Time-motion analysis revealed that nurses'' activities took up the most time in the workflow and contained a high frequency of shorter duration activities. Administrative assistants performed more activities near the beginning and end of the workflow. Overall, clinical trial tasks had a greater frequency than clinic routines or other general activities.Conclusions
This paper describes a method for modeling clinical trial workflow in UML and standardizing these workflow diagrams through a UML profile. In the increasingly global environment of clinical trials, the standardization of workflow modeling is a necessary precursor to conducting a comparative analysis of international clinical trials workflows. 相似文献999.
Ana Sofia Cacha?o Tania Carvalho Ana Cristina Santos Cátia Igreja Rita Fragoso Catarina Osório Manuela Ferreira Jacinta Serpa Sofia Correia Perpétua Pinto-do-ó Sérgio Dias 《PloS one》2010,5(2)
Background
Secondary bone marrow (BM) myelodysplastic syndromes (MDS) are increasingly common, as a result of radio or chemotherapy administered to a majority of cancer patients. Patients with secondary MDS have increased BM cell apoptosis, which results in BM dysfunction (cytopenias), and an increased risk of developing fatal acute leukemias. In the present study we asked whether TNF-α, known to regulate cell apoptosis, could modulate the onset of secondary MDS.Principal Findings
We show that TNF-α is induced by irradiation and regulates BM cells apoptosis in vitro and in vivo. In contrast to irradiated wild type (WT) mice, TNF-α deficient (TNF-α KO) mice or WT mice treated with a TNF-α-neutralizing antibody were partially protected from the apoptotic effects of irradiation. Next we established a 3-cycle irradiation protocol, in which mice were sub-lethally irradiated once monthly over a 3 month period. In this model, irradiated WT mice presented loss of microsatellite markers on BM cells, low white blood cell (WBC) counts, reduced megakaryocyte (MK) and platelet levels (thrombocytopenia) and macrocytic anemia, phenoypes that suggest the irradiation protocol resulted in BM dysfunction with clinical features of MDS. In contrast, TNF-α KO mice were protected from the irradiation effects: BM cell apoptosis following irradiation was significantly reduced, concomitant with sustained BM MK numbers and absence of other cytopenias. Moreover, irradiated WT mice with long term (≥5 months) BM dysfunction had increased BM angiogenesis, MMPs and VEGF and NFkB p65, suggestive of disease progression.Conclusion
Taken together, our data shows that TNF-α induction following irradiation modulates BM cell apoptosis and is a crucial event in BM dysfunction, secondary MDS onset and progression. 相似文献1000.
Abu S. G. Faruque Azharul Islam Khan Baitun Nahar S. M. Rafiqul Islam M. Nasif Hossain Syed Asif Abdullah Soroar Hossain Khan Md. Sabbir Hossain Feroz Hayat Khan Mukeshkumar Prajapati Yulia Widiati A. S. M. Mainul Hasan Minjoon Kim Jennie Musto Maya Vandenent John David Clemens Tahmeed Ahmed 《PLoS neglected tropical diseases》2021,15(9)
BackgroundBangladesh experienced a sudden, large influx of forcibly displaced persons from Myanmar in August 2017. A cholera outbreak occurred in the displaced population during September-December 2019. This study aims to describe the epidemiologic characteristics of cholera patients who were hospitalized in diarrhea treatment centers (DTCs) and sought care from settlements of Forcibly Displaced Myanmar Nationals (FDMN) as well as host country nationals during the cholera outbreak.MethodsDiarrhea Treatment Center (DTC) based surveillance was carried out among the FDMN and host population in Teknaf and Leda DTCs hospitalized for cholera during September-December 2019.ResultsDuring the study period, 147 individuals with cholera were hospitalized. The majority, 72% of patients reported to Leda DTC. Nearly 65% sought care from FDMN settlements. About 47% of the cholera individuals were children less than 5 years old and 42% were aged 15 years and more. Half of the cholera patients were females. FDMN often reported from Camp # 26 (45%), followed by Camp # 24 (36%), and Camp # 27 (12%). Eighty-two percent of the cholera patients reported watery diarrhea. Some or severe dehydration was observed in 65% of cholera individuals. Eighty-one percent of people with cholera received pre-packaged ORS at home. About 88% of FDMN cholera patients reported consumption of public tap water. Pit latrine without water seal was often used by FDMN cholera individuals (78%).ConclusionVigilance for cholera patients by routine surveillance, preparedness, and response readiness for surges and oral cholera vaccination campaigns can alleviate the threats of cholera. 相似文献