39 research outputs found
Subnormothermic perfusion with h2s donor ap39 improves dcd porcine renal graft outcomes in an ex vivo model of kidney preservation and reperfusion
This is the final published version, also available from MDPI via the DOI in this record.Cold preservation is the standard of care for renal grafts. However, research on alterna-tives like perfusion at higher temperatures and supplementing preservation solutions with hydrogen sulfide (H2S) has gained momentum. In this study, we investigated whether adding H2S donor AP39 to porcine blood during subnormothermic perfusion at 21 °C improves renal graft outcomes. Porcine kidneys were nephrectomized after 30 min of clamping the renal pedicles and treated to 4 h of static cold storage (SCS) on ice or ex vivo subnormothermic perfusion at 21 °C with autologous blood alone (SNT) or with AP39 (SNTAP). All kidneys were reperfused ex vivo with autologous blood at 37 °C for 4 h. Urine output, histopathology and RNAseq were used to evaluate the renal graft function, injury and gene expression profiles, respectively. The SNTAP group exhibited significantly higher urine output than other groups during preservation and reperfusion, along with significantly lower apoptotic injury compared to the SCS group. The SNTAP group also exhibited differential pro-survival gene expression patterns compared to the SCS (downregulation of pro-apoptotic genes) and SNT (downregulation of hypoxia response genes) groups. Subnormothermic perfusion at 21 °C with H2S-supplemented blood improves renal graft outcomes. Further research is needed to facilitate the clinical translation of this approach.Medical Research Council (MRC)Physicians Services Incorporated (PSI) FoundationLawson Research Institut
Ecthyma gangrenosum on the face of a malnourished child with Pseudomonas sepsis: Simulating Cancrum oris
Introduction: Ecthyma gangrenosum (EG) is a cutaneous lesion commonly caused by Pseudomonas aeruginosa that involves mainly the lower limbs and gluteal region, seen more in immunosuppressed patients with neutropenia. Cancrum oris (Noma) is a gangrenous necrosis of the face that begins as a gingival ulcer and progresses rapidly to destroy contiguous tissues in malnourished children.
Case Presentation: This article reports a case of facial EG which was similar to Noma in a malnourished child: a 16-month old girl with fever, cough, weight loss, watery stool and swelling on right cheek. She was febrile, pale, wasted with bilateral pitting pedal oedema. She had a solitary circumscribed round necrotic lesion, with surrounding hyperaemia on the right malar area which extended to destroy the right ala nasi. No intra-oral rashes but she had left ear discharge. She received blood transfusion, antibiotics, antiseptic wound care and nutritional rehabilitation.
Management and Outcome: Swabs of the lesion and ear discharge both revealed Gram-negative bacilli and culture yielded P. aeruginosa. Retroviral, Mantoux and Gene Xpert tests were negative. She had moderate anaemia, normal white blood cell count, and neutropaenia. Parenteral ceftriazone was changed to ciprofloxacin based on sensitivity results and lack of clinical response. The wound healed with residual scarring and partial destruction of right ala nasi.
Discussion: Although this patient had facial necrosis to suggest Noma, she did not have initial oral involvement, and clinical features such as Pseudomonas sepsis and neutropaenia suggested EG. Facial necrosis in malnourished children may be due to EG
Formation and structure of ionomer complexes from grafted polyelectrolytes
We discuss the structure and formation of Ionomer Complexes formed upon mixing a grafted block copolymer (poly(acrylic acid)-b-poly(acrylate methoxy poly(ethylene oxide)), PAA21-b-PAPEO14) with a linear polyelectrolyte (poly(N-methyl 2-vinyl pyridinium iodide), P2MVPI), called grafted block ionomer complexes (GBICs), and a chemically identical grafted copolymer (poly(acrylic acid)-co-poly(acrylate methoxy poly(ethylene oxide)), PAA28-co-PAPEO22) with a linear polyelectrolyte, called grafted ionomer complexes (GICs). Light scattering measurements show that GBICs are much bigger (~70–100 nm) and GICs are much smaller or comparable in size (6–22 nm) to regular complex coacervate core micelles (C3Ms). The mechanism of GICs formation is different from the formation of regular C3Ms and GBICs, and their size depends on the length of the homopolyelectrolyte. The sizes of GBICs and GICs slightly decrease with temperature increasing from 20 to 65 °C. This effect is stronger for GBICs than for GICs, is reversible for GICs and GBIC-PAPEO14/P2MVPI228, and shows some hysteresis for GBIC-PAPEO14/P2MVPI43. Self-consistent field (SCF) calculations for assembly of a grafted block copolymer (having clearly separated charged and grafted blocks) with an oppositely charged linear polyelectrolyte of length comparable to the charged copolymer block predict formation of relatively small spherical micelles (~6 nm), with a composition close to complete charge neutralization. The formation of micellar assemblies is suppressed if charged and grafted monomers are evenly distributed along the backbone, i.e., in case of a grafted copolymer. The very large difference between the sizes found experimentally for GBICs and the sizes predicted from SCF calculations supports the view that there is some secondary association mechanism. A possible mechanism is discussed
Noninvasive Diagnosis of Visceral Leishmaniasis:Development and Evaluation of Two Urine-Based Immunoassays for Detection of Leishmania donovani Infection in India
Visceral leishmaniasis (VL), one of the most prevalent parasitic diseasesin the developing world causes serious health concerns. Post kala-azar dermal leishmaniasis (PKDL) is a skin disease which occurs after treatment as a sequel to VL. Parasitological diagnosis involves invasive tissue aspiration which is tedious and painful. Commercially available immunochromatographic rapid diagnostic test such as rK39-RDT is used for field diagnosis of VL, detects antibodiesin serum samples. Urine sample is however, much easier in
collection,storage and handling than serum and would be a better alternative where collection of tissue aspirate or blood is impractical. In this study, we have developed and evaluated the performance of two urine-based diagnostic assays, ELISA and dipstick test, and
compared the results with serologicalrK39-RDT. Our study shows the capability of urinebased tests in detecting anti-Leishmania antibodies effectively for both VL and PKDL diagnosis. The ability of dipstick test to demonstrate negative results after six months in
90% of the VL cases after treatment could be useful as a test of clinical cure. Urine-based
tests can therefore replace the need for invasive practices and ensure better diagnosi
The c4h, tat, hppr and hppd Genes Prompted Engineering of Rosmarinic Acid Biosynthetic Pathway in Salvia miltiorrhiza Hairy Root Cultures
Rational engineering to produce biologically active plant compounds has been greatly impeded by our poor understanding of the regulatory and metabolic pathways underlying the biosynthesis of these compounds. Here we capitalized on our previously described gene-to-metabolite network in order to engineer rosmarinic acid (RA) biosynthesis pathway for the production of beneficial RA and lithospermic acid B (LAB) in Salvia miltiorrhiza hairy root cultures. Results showed their production was greatly elevated by (1) overexpression of single gene, including cinnamic acid 4-hydroxylase (c4h), tyrosine aminotransferase (tat), and 4-hydroxyphenylpyruvate reductase (hppr), (2) overexpression of both tat and hppr, and (3) suppression of 4-hydroxyphenylpyruvate dioxygenase (hppd). Co-expression of tat/hppr produced the most abundant RA (906 mg/liter) and LAB (992 mg/liter), which were 4.3 and 3.2-fold more than in their wild-type (wt) counterparts respectively. And the value of RA concentration was also higher than that reported before, that produced by means of nutrient medium optimization or elicitor treatment. It is the first report of boosting RA and LAB biosynthesis through genetic manipulation, providing an effective approach for their large-scale commercial production by using hairy root culture systems as bioreactors
Grafted ionomer complexes and their effect on protein adsorption on silica and polysulfone surfaces
We have studied the formation and the stability of ionomer complexes from grafted copolymers (GICs) in solution and the influence of GIC coatings on the adsorption of the proteins β-lactoglobulin (β-lac), bovine serum albumin (BSA), and lysozyme (Lsz) on silica and polysulfone. The GICs consist of the grafted copolymer PAA28-co-PAPEO22 {poly(acrylic acid)-co-poly[acrylate methoxy poly(ethylene oxide)]} with negatively charged AA and neutral APEO groups, and the positively charged homopolymers: P2MVPI43 [poly(N-methyl 2-vinyl pyridinium iodide)] and PAH∙HCl160 [poly(allylamine hydrochloride)]. In solution, these aggregates are characterized by means of dynamic and static light scattering. They appear to be assemblies with hydrodynamic radii of 8 nm (GIC-PAPEO22/P2MVPI43) and 22 nm (GIC-PAPEO22/PAH∙HCl160), respectively. The GICs partly disintegrate in solution at salt concentrations above 10 mM NaCl. Adsorption of GICs and proteins has been studied with fixed angle optical reflectometry at salt concentrations ranging from 1 to 50 mM NaCl. Adsorption of GICs results in high density PEO side chains on the surface. Higher densities were obtained for GICs consisting of PAH∙HCl160 (1.6 ÷ 1.9 chains/nm2) than of P2MVPI43 (0.6 ÷ 1.5 chains/nm2). Both GIC coatings strongly suppress adsorption of all proteins on silica (>90%); however, reduction of protein adsorption on polysulfone depends on the composition of the coating and the type of protein. We observed a moderate reduction of β-lac and Lsz adsorption (>60%). Adsorption of BSA on the GIC-PAPEO22/P2MVPI43 coating is moderately reduced, but on the GIC-PAPEO22/PAH∙HCl160 coating it is enhanced
Punica granatum L. protects mice against hexavalent chromium-induced genotoxicity
This study investigated the chemoprotective effects of Punica granatum L. (Punicaceae) fruits alcoholic extract (PGE) on mice exposed to hexavalent chromium [Cr(VI)]. Animals were pretreated with PGE (25, 50 or 75 mg/kg/day) for 10 days and subsequently exposed to a sub-lethal dose of Cr(VI) (30 mg/kg). The frequency of micronucleated polychromatic erythrocytes in the bone marrow was investigated and the Cr(VI) levels were measured in the kidneys, liver and plasm. For the survival analysis, mice were previously treated with PGE for 10 days and exposed to a single lethal dose of Cr(VI) (50 mg/kg). Exposure to a sub-lethal dose of Cr(VI) induced a significant increase in the frequency of micronucleated cells. However, the prophylactic treatment with PGE led to a reduction of 44.5% (25 mg/kg), 86.3% (50 mg/kg) and 64.2% (75 mg/kg) in the incidence of micronuclei. In addition, the 50 mg/kg dose of PGE produced a higher chemoprotective effect, since the survival rate was 90%, when compared to that of the non-treated group. In these animals, reduced amounts of chromium were detected in the biological materials, in comparison with the other groups. Taken together, the results demonstrated that PGE exerts a protective effect against Cr(VI)-induced genotoxicity
Molecular cloning and structural characterization of HMG-CoA reductase gene from <i style="">Catharanthus roseus</i> (L.) G. Donn. cv. Albus
16-22The
3-hydroxy-3-methyl glutaryl-CoA reductase (HMGR) catalyzes the conversion of
HMG-CoA to mevalonate, the first committed step in isoprenoid biosynthesis
pathway in plants. HMG-CoA reductase gene was amplified from the Catharanthus roseus (L.) G. Donn. cv.
Albus by polymerase chain reaction (PCR) with primers designed using published
sequence of HMG-CoA reductase c-DNA of C. roseus cv. Little Delicata (Acc. No. M96068). PS2 SERVER was used to generate three dimensional (3-D) structure of the
enzyme using human HMG-CoA reductase as template. The
structure was evaluated at various web interfaced
servers, i.e., PROCHEK, Profunc and PDBsum, for checking the stereo interfaced
quality of the structure in terms of bonds, bond angles, dihedral angles,
structural as well as functional domains. The generated model was visualized
using the Rasmol. The results of these studies revealed that HMG-CoA reductase
gene from cv. Albus had 99% sequence
homology with hmgr cDNA of cv. Little Delicata. The amino acid sequence of the HMGR protein of cv.
Albus was found closely
related to the members of the family Solanaceae and distantly related to the members
of the families Euphorbiaceae and Brassicaceae. The enzyme has N-terminal
transmembrane domain and a C-terminal catalytic domain with active sites that
can bind to HMG-CoA and NADPH2. The fold of the substrate domain is
unique and resembles the prism with 28-residue helix forming the central core.
The homology model of enzyme generated in the present study, hence, could be
used in determining the mechanistic function of this important class of
proteins