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991.
Kenneth Blum David Han John Femino David E. Smith Scott Saunders Thomas Simpatico Stephen J. Schoenthaler Marlene Oscar-Berman Mark S. Gold 《PloS one》2014,9(9)
This is the first quantitative analysis of data from urine drug tests for compliance to treatment medications and abstinence from drug abuse across “levels of care” in six eastern states of America. Comprehensive Analysis of Reported Drugs (CARD) data was used in this post-hoc retrospective observational study from 10,570 patients, filtered to include a total of 2,919 patients prescribed at least one treatment medication during 2010 and 2011. The first and last urine samples (5,838 specimens) were analyzed; compliance to treatment medications and abstinence from drugs of abuse supported treatment effectiveness for many. Compared to non-compliant patients, compliant patients were marginally less likely to abuse opioids, cannabinoids, and ethanol during treatment although more likely to abuse benzodiazepines. Almost 17% of the non-abstinent patients used benzodiazepines, 15% used opiates, and 10% used cocaine during treatment. Compliance was significantly higher in residential than in the non-residential treatment facilities. Independent of level of care, 67.2% of the patients (n = 1963; P<.001) had every treatment medication found in both first and last urine specimens (compliance). In addition, 39.2% of the patients (n = 1143; P<.001) had no substance of abuse detected in either the first or last urine samples (abstinence). Moreover, in 2010, 16.9% of the patients (n = 57) were abstinent at first but not at last urine (deteriorating abstinence), the percentage dropped to 13.3% (n = 174) in 2011; this improvement over years was statistically significant. A longitudinal analysis for abstinence and compliance was studied in a randomized subset from 2011, (n = 511) representing 17.5% of the total cohort. A statistically significant upward trend (p = 2.353×10−8) of abstinence rates as well as a similar but stronger trend for compliance ((p = 2.200×10−16) was found. Being cognizant of the trend toward drug urine testing being linked to medical necessity eliminating abusive screening, the interpretation of these valuable results require further intensive investigation. 相似文献
992.
993.
994.
Kelvin K. W. To Herman Tse Wan-Mui Chan Garnet K. Y. Choi Anna J. X. Zhang Siddharth Sridhar Sally C. Y. Wong Jasper F. W. Chan Andy S. F. Chan Patrick C. Y. Woo Susanna K. P. Lau Janice Y. C. Lo Kwok-Hung Chan Vincent C. C. Cheng Kwok-Yung Yuen 《PLoS neglected tropical diseases》2014,8(12)
Chlamydophila psittaci is found worldwide, but is particularly common among psittacine birds in tropical and subtropical regions. While investigating a human psittacosis outbreak that was associated with avian chlamydiosis in Hong Kong, we identified a novel adenovirus in epidemiologically linked Mealy Parrots, which was not present in healthy birds unrelated to the outbreak or in other animals. The novel adenovirus (tentatively named Psittacine adenovirus HKU1) was most closely related to Duck adenovirus A in the Atadenovirus genus. Sequencing showed that the Psittacine adenovirus HKU1 genome consists of 31,735 nucleotides. Comparative genome analysis showed that the Psittacine adenovirus HKU1 genome contains 23 open reading frames (ORFs) with sequence similarity to known adenoviral genes, and six additional ORFs at the 3′ end of the genome. Similar to Duck adenovirus A, the novel adenovirus lacks LH1, LH2 and LH3, which distinguishes it from other viruses in the Atadenovirus genus. Notably, fiber-2 protein, which is present in Aviadenovirus but not Atadenovirus, is also present in Psittacine adenovirus HKU1. Psittacine adenovirus HKU1 had pairwise amino acid sequence identities of 50.3–54.0% for the DNA polymerase, 64.6–70.7% for the penton protein, and 66.1–74.0% for the hexon protein with other Atadenovirus. The C. psittaci bacterial load was positively correlated with adenovirus viral load in the lung. Immunostaining for fiber protein expression was positive in lung and liver tissue cells of affected parrots, confirming active viral replication. No other viruses were found. This is the first documentation of an adenovirus-C. psittaci co-infection in an avian species that was associated with a human outbreak of psittacosis. Viral-bacterial co-infection often increases disease severity in both humans and animals. The role of viral-bacterial co-infection in animal-to-human transmission of infectious agents has not received sufficient attention and should be emphasized in the investigation of disease outbreaks in human and animals. 相似文献
995.
Francisco-Jose Fernandez-Gomez Fanny Jumeau Maxime Derisbourg Sylvie Burnouf Hélène Tran Sabiha Eddarkaoui Hélène Obriot Virginie Dutoit-Lefevre Vincent Deramecourt Valérie Mitchell Didier Lefranc Malika Hamdane David Blum Luc Buée Valérie Buée-Scherrer Nicolas Sergeant 《Journal of visualized experiments : JoVE》2014,(86)
Two-dimensional gel electrophoresis (2DE) is a powerful tool to uncover proteome modifications potentially related to different physiological or pathological conditions. Basically, this technique is based on the separation of proteins according to their isoelectric point in a first step, and secondly according to their molecular weights by SDS polyacrylamide gel electrophoresis (SDS-PAGE). In this report an optimized sample preparation protocol for little amount of human post-mortem and mouse brain tissue is described. This method enables to perform both two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) and mini 2DE immunoblotting. The combination of these approaches allows one to not only find new proteins and/or protein modifications in their expression thanks to its compatibility with mass spectrometry detection, but also a new insight into markers validation. Thus, mini-2DE coupled to western blotting permits to identify and validate post-translational modifications, proteins catabolism and provides a qualitative comparison among different conditions and/or treatments. Herein, we provide a method to study components of protein aggregates found in AD and Lewy body dementia such as the amyloid-beta peptide and the alpha-synuclein. Our method can thus be adapted for the analysis of the proteome and insoluble proteins extract from human brain tissue and mice models too. In parallel, it may provide useful information for the study of molecular and cellular pathways involved in neurodegenerative diseases as well as potential novel biomarkers and therapeutic targets. 相似文献
996.
Thomas H. Cribb Sylvie Pichelin Vincent Dufour Rodney A. Bray Claude Chauvet Elizabeth Faliex Ren Galzin Cdrik M. Lo Alain Lo-Yat Serge Morand Mark C. Rigby Pierre Sasal 《International journal for parasitology》2000,30(14):185-1451
Recruiting coral reef fish larvae from 38 species and 19 families from New Caledonia were examined for parasites. We found 13 parasite species (Platyhelminthes: Monogenea, Cestoda and Trematoda) but no acanthocephalan, crustacean or nematode parasites. Over 23% of individual fish were infected. Didymozoid metacercariae were the most abundant parasites. We conclude that most of the parasites are pelagic species that become ‘lost’ once the fish larvae have recruited to the reef. Larval coral reef fish probably contribute little to the dispersal of the parasites of the adult fish so that parasite dispersal is more difficult than that of the fish themselves. 相似文献
997.
Evolutionarily divergent extradiol dioxygenases possess higher specificities for polychlorinated biphenyl metabolites 下载免费PDF全文
Fortin PD Lo AT Haro MA Kaschabek SR Reineke W Eltis LD 《Journal of bacteriology》2005,187(2):415-421
The reactivities of four evolutionarily divergent extradiol dioxygenases towards mono-, di-, and trichlorinated (triCl) 2,3-dihydroxybiphenyls (DHBs) were investigated: 2,3-dihydroxybiphenyl dioxygenase (EC 1.13.11.39) from Burkholderia sp. strain LB400 (DHBDLB400), DHBDP6-I and DHBDP6-III from Rhodococcus globerulus P6, and 2,2',3-trihydroxybiphenyl dioxygenase from Sphingomonas sp. strain RW1 (THBDRW1). The specificity of each isozyme for particular DHBs differed by up to 3 orders of magnitude. Interestingly, the Kmapp values of each isozyme for the tested polychlorinated DHBs were invariably lower than those of monochlorinated DHBs. Moreover, each enzyme cleaved at least one of the tested chlorinated (Cl) DHBs better than it cleaved DHB (e.g., apparent specificity constants for 3',5'-dichlorinated [diCl] DHB were 2 to 13.4 times higher than for DHB). These results are consistent with structural data and modeling studies which indicate that the substrate-binding pocket of the DHBDs is hydrophobic and can accommodate the Cl DHBs, particularly in the distal portion of the pocket. Although the activity of DHBDP6-III was generally lower than that of the other three enzymes, six of eight tested Cl DHBs were better substrates for DHBDP6-III than was DHB. Indeed, DHBDP6-III had the highest apparent specificity for 4,3',5'-triCl DHB and cleaved this compound better than two of the other enzymes. Of the four enzymes, THBDRW1 had the highest specificity for 2'-Cl DHB and was at least five times more resistant to inactivation by 2'-Cl DHB, consistent with the similarity between the latter and 2,2',3-trihydroxybiphenyl. Nonetheless, THBDRW1 had the lowest specificity for 2',6'-diCl DHB and, like the other enzymes, was unable to cleave this critical PCB metabolite (kcatapp < 0.001 s(-1)). 相似文献
998.
Rodolfo Carvalho Pacagnella Jo?o Paulo Souza Jill Durocher Pablo Perel Jennifer Blum Beverly Winikoff Ahmet Metin Gülmezoglu 《PloS one》2013,8(3)
Introduction
This systematic review examines the relationship between blood loss and clinical signs and explores its use to trigger clinical interventions in the management of obstetric haemorrhage.Methods
A systematic review of the literature was carried out using a comprehensive search strategy to identify studies presenting data on the relationship of clinical signs & symptoms and blood loss. Methodological quality was assessed using the STROBE checklist and the general guidelines of MOOSE.Results
30 studies were included and five were performed in women with pregnancy-related haemorrhage (other studies were carried in non-obstetric populations). Heart rate (HR), systolic blood pressure (SBP) and shock index were the parameters most frequently studied. An association between blood loss and HR changes was observed in 22 out of 24 studies, and between blood loss and SBP was observed in 17 out of 23 studies. An association was found in all papers reporting on the relationship of shock index and blood loss. Seven studies have used Receiver Operating Characteristic Curves to determine the accuracy of clinical signs in predicting blood loss. In those studies the AUC ranged from 0.56 to 0.74 for HR, from 0.56 to 0.79 for SBP and from 0.77 to 0.84 for shock index. In some studies, HR, SBP and shock index were associated with increased mortality.Conclusion
We found a substantial variability in the relationship between blood loss and clinical signs, making it difficult to establish specific cut-off points for clinical signs that could be used as triggers for clinical interventions. However, the shock index can be an accurate indicator of compensatory changes in the cardiovascular system due to blood loss. Considering that most of the evidence included in this systematic review is derived from studies in non-obstetric populations, further research on the use of the shock index in obstetric populations is needed. 相似文献999.
Balasubramanian L Ahmed A Lo CM Sham JS Yip KP 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(4):R1586-R1594
Integrins are transmembrane heterodimeric proteins that link extracellular matrix (ECM) to cytoskeleton and have been shown to function as mechanotransducers in nonmuscle cells. Synthetic integrin-binding peptide triggers Ca(2+) mobilization and contraction in vascular smooth muscle cells (VSMCs) of rat afferent arteriole, indicating that interactions between the ECM and integrins modulate vascular tone. To examine whether integrins transduce extracellular mechanical stress into intracellular Ca(2+) signaling events in VSMCs, unidirectional mechanical force was applied to freshly isolated renal VSMCs through paramagnetic beads coated with fibronectin (natural ligand of alpha(5)beta(1)-integrin in VSMCs). Pulling of fibronectin-coated beads with an electromagnet triggered Ca(2+) sparks, followed by global Ca(2+) mobilization. Paramagnetic beads coated with low-density lipoprotein, whose receptors are not linked to cytoskeleton, were minimally effective in triggering Ca(2+) sparks and global Ca(2+) mobilization. Preincubation with ryanodine, cytochalasin-D, or colchicine substantially reduced the occurrence of Ca(2+) sparks triggered by fibronectin-coated beads. Binding of VSMCs with antibodies specific to the extracellular domains of alpha(5-) and beta(1)-integrins triggered Ca(2+) sparks simulating the effects of fibronectin-coated beads. Preincubation of microperfused afferent arterioles with ryanodine or integrin-specific binding peptide inhibited pressure-induced myogenic constriction. In conclusion, integrins transduce mechanical force into intracellular Ca(2+) signaling events in renal VSMCs. Integrin-mediated mechanotransduction is probably involved in myogenic response of afferent arterioles. 相似文献
1000.
Alessandro Balestrieri Luigi Remonti Nicola Ferrari Angelo Ferrari Tatiana Lo Valvo Serena Robetto Riccardo Orusa 《European Journal of Wildlife Research》2006,52(3):196-201
Between 2001 and 2004, 229 foxes, 36 stone martens and 48 badgers from the western Italian Alps were examined for sarcoptic mange and for gastrointestinal helminths to investigate their prevalence and geographical distribution and to point out the existence of potential interactions among them. Sarcoptic mange was observed in 25.3±2.8% SE of foxes and in 5.6±3.8% SE of stone martens, while no badger was found infected. Helminths belonged to Cestoidea Cyclophillidea (3.0±1.1% SE), Nematoda Trichurida (Capillaria aerophila and Trichuris vulpis: 6.5±1.6% SE; Trichinella britovi: 3.0±1.1% SE), Ascaridida (12.2±2.2% SE) and Strongylida (6.9±1.7% SE). Sarcoptic mange infection and the presence of helminths proved to be associated, with mangy foxes showing significantly higher prevalence of both cestode and nematode (particularly Ascaridida) worms. Moreover, considering three clusters of parasites (S. scabiei, nematodes and cestodes), more foxes than expected hosted simultaneously 2 and 3 taxa. These evidences suggest the existence of some kind of interaction, whose modalities and implications are discussed in this paper. 相似文献