Extracorporeal therapies (ET) are increasingly used in pediatric settings as adjuvant therapeutic strategies for overwhelming inflammatory conditions. Although these treatments seem to be effective for removing inflammatory mediators, their influence on antimicrobials pharmacokinetic should not be neglected. A prospective observational study of children admitted to the pediatric intensive care unit (PICU) with a diagnosis of sepsis/septic shock.
View Article and Find Full Text PDFBackground: Policy advisers are seeking robust evidence on the effectiveness of measures, such as promoting walking and cycling, that potentially offer multiple benefits, including enhanced health through physical activity, alongside reductions in energy use, traffic congestion and carbon emissions. This paper outlines the 'ACTIVE' study, designed to test whether the Model Communities Programme in two New Zealand cities is increasing walking and cycling. The intervention consists of the introduction of cycle and walkway infrastructure, along with measures to encourage active travel.
View Article and Find Full Text PDFNematode anthelminthic resistance is widespread for the 3 major drug classes commonly used in agriculture: benzamidazoles, macrocyclic lactones, and nicotinic agonists e.g. levamisole.
View Article and Find Full Text PDFBackground: Gene identification and sequence determination are critical requirements for many biological, genomic, and bioinformatic studies. With the advent of next generation sequencing (NGS) technologies, such determinations are predominantly accomplished in silico for organisms for which the genome is known or for which there exists substantial gene sequence information. Without detailed genomic/gene information, in silico sequence determination is not straightforward, and full coding sequence determination typically involves time- and labor-intensive PCR-based amplification and cloning methods.
View Article and Find Full Text PDFPrevious works demonstrated that various species of Leishmania promastigotes exhibit differential sensitivity to complement-mediated lysis (CML) during development. Upon exposure to normal human serum (NHS), cultures of Leishmania chagasi promastigotes recently isolated from infected hamsters (fewer than 5 in vitro passages) are CML-sensitive when in the logarithmic growth phase but become CML-resistant upon transition to the stationary culture phase. Visualization by light and electron microscopy revealed dramatic morphological differences between promastigotes from the 2 culture phases following exposure to NHS.
View Article and Find Full Text PDFLeishmania chagasi causes visceral leishmaniasis, a potentially fatal disease of humans. Within the sand fly vector, L. chagasi replicates as promastigotes which undergo complex changes in morphology as they progress from early stage procyclic promastigotes, to intermediate stage leptomonad and nectomonad promastigotes, and ultimately to terminal stage metacyclic promastigotes that are highly infective to vertebrates.
View Article and Find Full Text PDFLeishmania chagasi, a causal agent of visceral leishmaniasis, requires passage through lab animals such as hamsters to maintain its virulence. Hamster infection is typically accomplished via cardiac puncture or intraperitoneal injection, procedures accompanied by risks of increased animal stress and death. The use of the hamster model also necessitates a regular supply of infected animals, because L.
View Article and Find Full Text PDFSerial passage of axenically cultured Leishmania chagasi promastigotes results in a progressive diminution in resistance to complement-mediated lysis (CML), whereas high CML resistance is seen in infectious metacyclic promastigotes from the sandfly vector as well as metacyclic-like promastigotes within low-passage cultures at stationary growth phase. As we previously reported, in a screen seeking to identify novel genes involved in CML resistance: (1) a genomic cosmid library derived from DNA of CML-resistant L. chagasi promastigotes was transfected into high-passage (constitutively CML-sensitive) L.
View Article and Find Full Text PDFPast studies showed that Leishmania spp. promastigotes exhibit differential sensitivity to complement mediated lysis (CML) during development in vitro and in vivo. Leishmania chagasi promastigotes in cultures during logarithmic and stationary growth phases are CML-sensitive or CML-resistant when exposed to human serum, respectively, but only in cultures recently initiated with parasites from infected animals; serially passaged cultures become constitutively CML-sensitive regardless of growth phase.
View Article and Find Full Text PDFThe mRNAs encoding promastigote surface antigen (PSA) of Leishmania chagasi have previously been shown to increase about 30-fold as in vitro cultured parasites progress from logarithmic to stationary phase, growth phases that are, respectively associated with parasites having low and high infectivity to mammals. Experiments reported here establish by western blot analysis that PSA proteins of 44 and 66 kDa also increase about 30-fold as parasite cultures reach stationary phase. Serial passage of parasite cultures resulted in a progressive reduction in PSA protein and RNA abundance to levels less than 3% that of cultures newly-initiated with parasites derived from a parasitized rodent.
View Article and Find Full Text PDFMSP (GP63) and PSA (GP46) are abundant 63- and 46-kDa glycolipid-anchored proteins on the surface of the promastigote form of most Leishmania species. MSP is a zinc metalloprotease that confers resistance to host complement-mediated lysis. PSA contains internal repeats of 24 amino acids, and its function is unknown.
View Article and Find Full Text PDFStudy Design: An experimental study of respiratory function and kinematics of the diaphragm and pelvic floor in subjects with a clinical diagnosis of sacroiliac joint pain and in a comparable pain-free subject group was conducted.
Objective: To gain insight into the motor control strategies of subjects with sacroiliac joint pain and the resultant effect on breathing pattern.
Summary Of Background Data: The active straight-leg-raise test has been proposed as a clinical test for the assessment of load transfer through the pelvis.
Affinity chromatographic methods were developed for the one-step purification to homogeneity of recombinant soluble epoxide hydrolases (sEHs) from cress and potato. The enzymes are monomeric, with masses of 36 and 39 kDa and pI values of 4.5 and 5.
View Article and Find Full Text PDFMol Biochem Parasitol
September 1998
The surface protease GP63 of Leishmania chagasi is encoded by a cluster of more than 18 tandem major surface protease (msp) genes belonging to three classes (mspL, mspS, mspC). mspL and mspS transcripts are differentially expressed during parasite growth. RNAs from mspS genes predominate during stationary phase, the time when parasite virulence and GP63 expression are maximal.
View Article and Find Full Text PDFGP46 is an abundant glycoprotein of 46 kDa on the surface of the promastigote form of most Leishmania species. We show that the steady state level of GP46 mRNA increases >>30-fold as Leishmania chagasi promastigotes develop in vitro from a less infectious form during logarithmic growth to a highly infectious form in the stationary phase of cultivation. Nuclear run-on experiments demonstrate that this increase in GP46 mRNA abundance is regulated post-transcriptionally.
View Article and Find Full Text PDFMammalian soluble and microsomal epoxide hydrolases have been proposed to belong to the family of alpha/beta-hydrolase-fold enzymes. These enzymes hydrolyse their substrates by a catalytic triad, with the first step of the enzymatic reaction being the formation of a covalent enzyme-substrate ester. In the present paper, we describe the direct visualization of the ester formation between rat microsomal epoxide hydrolase and its substrate.
View Article and Find Full Text PDFHuman liver microsomal fractions metabolized arachidonic acid in the presence of NADPH yielding epoxyeicosatrienoic acids and their hydration products, dihydroxyeicosatrienoic acids, as the principal reaction products. Inhibition studies using polyclonal antibodies prepared against recombinant CYP2C8, an abundant human liver cytochrome P450 epoxygenase, demonstrated 85-90% inhibition of arachidonic acid epoxide formation. Both epoxyeicosatrienoic acids and dihydroxyeicosatrienoic acids were detected in large amounts in human liver using gas chromatography/mass spectrometry.
View Article and Find Full Text PDFIn order to investigate the involvement of amino acids in the catalytic mechanism of the soluble epoxide hydrolase, different mutants of the murine enzyme were produced using the baculovirus expression system. Our results are consistent with the involvement of Asp-333 and His-523 in a catalytic mechanism similar to that of other alpha/beta hydrolase fold enzymes. Mutation of His-263 to asparagine led to the loss of approximately half the specific activity compared to wild-type enzyme.
View Article and Find Full Text PDFWe have analyzed amino acid sequence relationships among soluble and microsomal epoxide hydrolases, haloacid dehalogenases, and a haloalkane dehalogenase. The amino-terminal residues (1-229) of mammalian soluble epoxide hydrolase are homologous to a haloacid dehalogenase. The carboxy-terminal residues (230-554) of mammalian soluble epoxide hydrolase are homologous to haloalkane dehalogenase, to plant soluble epoxide hydrolase, and to microsomal epoxide hydrolase.
View Article and Find Full Text PDFA cDNA (1122 bp) was isolated from a cDNA library prepared from Arabidopsis thaliana L. that had been subjected to drought stress for 1 h. The sequencing of a genomic clone corresponding to the cDNA and S1 mapping analysis revealed that the cDNA lacked the first 6 bp from its translational start (ATG).
View Article and Find Full Text PDFFive cDNAs encoding a putative soluble epoxide hydrolase (sEH) from potato were isolated and characterized. The cDNAs contained open reading frames encoding 36 kDa polypeptides which were highly homologous to the carboxy terminal region of mammalian sEH. When one of the cDNAs was expressed in a baculovirus system a soluble 38 kDa protein with epoxide hydrolase activity was produced.
View Article and Find Full Text PDFThe gene for juvenile hormone esterase (JHE) was cloned from Heliothis virescens (Lepidoptera: Noctuidae). A genomic library was constructed from embryonic DNA and screened with a homologous N-terminal probe from the JHE cDNA. Five genomic clones were isolated and analyzed by dot blot hybridization using regions of the JHE cDNA as probes.
View Article and Find Full Text PDFBiochem Biophys Res Commun
February 1994
A putative covalent, alpha-hydroxyacyl intermediate was isolated by the brief exposure of murine soluble epoxide hydrolase to its substrate. The reaction was reversed by time and blocked by competitive inhibitors. The formation of the intermediate was dependent upon the concentration of the enzyme and was increased by incubation under acidic conditions.
View Article and Find Full Text PDFDirect comparison of the amino acid sequences of microsomal and soluble epoxide hydrolase superficially indicates that these enzymes are unrelated. Both proteins, however, share significant sequence similarity to a bacterial haloalkane dehalogenase that has earlier been shown to belong to the alpha/beta hydrolase fold family of enzymes. The catalytic mechanism for the dehalogenase has been elucidated in detail [Verschueren et al.
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