Bactofection with Toll-Like Receptor 4 in a Murine Model of Urinary Tract Infection

The role of innate immunity in the prevention of urinary tract infection is well-documented. Toll-like receptor 4 (TLR4) is a major determinant of innate immune response. In an animal model of urinary tract infection, bactofection-mediated gene transfer of TLR4 was tested in a preventive approach. Bactofection with TLR4 reduced the colonization with uropathogenic Escherichia coli by 91% in the kidney and by 41% in the bladder. Reduced colonization was associated with lower oxidative stress and expression of monocyte chemoattractant protein-1 and myeloperoxidase in the kidney. Bactofection with TLR4 was successful in the prevention of ascending pyelonephritis. Further studies should focus on long-term effects, the dose response and the potential therapeutic use in models of chronic urinary tract infection.     

Molecular Epidemiology of Rabies Viruses Circulating in Two Rabies Endemic Provinces of Laos, 2011–2012: Regional Diversity in Southeast Asia

BackgroundAlthough rabies is endemic in Laos, genetic characterization of the viruses in this country is limited. There are growing concerns that development in the region may have increased transport of dog through Laos for regional dog meat consumption, and that this may cause spillover of the viruses from dogs brought here from other countries. This study was therefore undertaken to evaluate the current rabies situation and the genetic characteristics of rabies viruses currently circulating in Laos.MethodsWe determined the rate of rabies-positive samples by analyzing data from animal samples submitted to the Lao Ministry of Agriculture and Forestry’s National Animal Health Centre rabies laboratory from 2004 through 2011. Twenty-three rabies-positive samples were used for viral genetic characterization. Full genome sequencing was performed on two rabies viruses.ResultsRabies-positive samples increased substantially from 40.5% in 2004 to 60.2% in 2009 and continued at this level during the study period. More than 99% of the samples were from dogs, followed by cats and monkeys. Phylogenetic analyses showed that three rabies virus lineages belonging to the Southeast Asian cluster are currently circulating in Laos; these are closely related to viruses from Thailand, Cambodia and Vietnam. Lineages of the circulating Laos rabies viruses diverged from common ancestors as recently as 44.2 years and as much as 55.3 years ago, indicating periodic virus invasions.ConclusionThere is an increasing trend of rabies in Laotian animals. Similar to other rabies-endemic countries, dogs are the main viral reservoir. Three viral lineages closely related to viruses from neighboring countries are currently circulating in Laos. Data provide evidence of periodic historic exchanges of the viruses with neighboring countries, but no recent invasion.     

Dexamethasone‐loaded biopolymeric nanoparticles promote gingival fibroblasts differentiation

Polymer‐based nanoparticles (NPs) can be efficiently used for the delivery of bioactive molecules for both in vitro and in vivo applications affording high drug loading and controlled release profiles. Within this framework polylactic‐co‐glycolic acid (PLGA) NPs with a diameter of 290 ± 41 nm have been fabricated and loaded with dexamethasone (DXM) using a patented procedure. The aim of the project was to setup a controlled delivery system to promote the in vitro differentiation of Human Gingival Fibroblasts (HGFs). First the uptake of fluorescent PLGA NPs by HGFs cells was investigated; then experiments were also addressed to analyze the specific cell response to DXM, in order to evaluate its functional efficiency in comparison with its conventional addition to the culture medium. The results showed that cells treated with DXM‐loaded NPs acquired the osteoblast phenotype faster in comparison to those treated with the free drug. The slow and sustained release of DXM from PLGA NPs produced a constant and uniform concentration of drug inside cells with long‐term and enhanced biochemical effects. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1381–1387, 2015     

Chemical Composition and Antipathogenic Activity of Artemisia annua Essential Oil from Romania

The essential oil extracted by hydrodistillation from Romanian Artemisia annua aerial parts was characterized by GC/MS analysis, which allowed the identification of 94.64% of the total oil composition. The main components were camphor (17.74%), α‐pinene (9.66%), germacrene D (7.55%), 1,8‐cineole (7.24%), trans‐β‐caryophyllene (7.02%), and artemisia ketone (6.26%). The antimicrobial activity of this essential oil was evaluated by determining the following parameters: minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), minimal fungicidal concentration (MFC), and minimal biofilm eradication concentration (MBEC). Moreover, the soluble virulence factors were quantified with different biochemical substrates incorporated in the culture media. The reference and resistant, clinical strains proved to be susceptible to the A. annua oil, with MICs ranging from 0.51 to 16.33 mg/ml. The tested essential oil also showed good antibiofilm activity, inhibiting both the initial stage of the microbial cell adhesion to the inert substratum and the preformed mature biofilm. When used at subinhibitory concentrations, the essential oil proved to inhibit the phenotypic expression of five soluble virulence factors (hemolysins, gelatinase, DNase, lipases, and lecithinases). Briefly, the present results showed that the A. annua essential oil contained antimicrobial compounds with selective activity on Gram‐positive and Gram‐negative bacterial strains as well as on yeast strains and which also interfere with the expression of cell‐associated and soluble virulence factors.     

The c13 Ring from a Thermoalkaliphilic ATP Synthase Reveals an Extended Diameter Due to a Special Structural Region

We have structurally characterized the c-ring from the thermoalkaliphilic Bacillus sp. strain TA2.A1 F₁F_o-ATP synthase. Atomic force microscopy imaging and cryo-electron microscopy analyses confirm previous mass spectrometric data indicating that this c-ring contains 13 c-subunits. The cryo-electron microscopy map obtained from two-dimensional crystals shows less closely packed helices in the inner ring compared to those of Na⁺-binding c₁₁ rings. The inner ring of α-helices in c₁₁ rings harbors a conserved GxGxGxGxG motif, with glycines located at the interface between c-subunits, which is responsible for the close packing of these helices. This glycine motif is altered in the c₁₃ ring of Bacillus sp. strain TA2.A1 to AxGxSxGxS, leading to a change in c-c subunit contacts and thereby enlarging the c-ring diameter to host a greater number of c-subunits. An altered glycine motif is a typical feature of c-subunit sequences in alkaliphilic Bacillus species. We propose that enlarged c-rings in proton-dependent F-ATP synthases may represent an adaptation to facilitate ATP synthesis at low overall proton-motive force, as occurs in bacteria that grow at alkaline pH.     

Copper(II) complexes with an avian prion N-terminal region and their potential SOD-like activity

Potentiometric and spectroscopic (UV-Vis, CD and EPR) studies were carried out on copper(II) complexes with chicken prion protein N-terminal fragments, Ac-(PHNPGY)₄-NH₂, and the mutated residue, Ac-(PHNPGF)₄-NH₂, to assess the role of tyrosine in the copper coordination. Both thermodynamic and spectroscopic results indicate that chicken prion fragments are not able to bind more than two copper ions and only with the involvement of side chain tyrosine groups. The prevailing complex shows one copper ion bound to four imidazole nitrogen atoms in the 1:1 metal to ligand ratio systems. The superoxide dismutase (SOD)-like activity of copper(II) complexes with the avian peptides and mammal analogue, Ac-(PHGGGWGQ)₄-NH₂, was also investigated by means of Pulse radiolysis. The copper(II) complexes with avian peptides do not display SOD-like activity, while very low activity has been detected for the copper(II) complexes with mammalian tetraoctarepeat.     

Mycosis Due to Tropicoporus tropicalis (= Inonotus tropicalis) in a Domestic Dog

Mycopathologia - Mycelial basidiomycetes rarely produce mycoses in animals including humans. We report a case of a 9-year-old female mongrel dog with lesions in the prescapular lymph nodes. The...     

Transmyocardial revascularization aggravates myocardial ischemia around the channels in the immediate phase

We examined whether transmyocardial revascularization (TMR) relieves myocardial ischemia by increasing regional perfusion via the transmural channels in acute canine experiments. Regional blood flow during transient coronary ligation (2 min) was compared before and 30 min after TMR, and at the third transient ischemia the mid-left ventricle (LV) was cut and immediately frozen along the short axis for the analysis of NADH fluorescence in the regions around the TMR channels. In low-resolution analysis (2-4 g tissue or 2-3 cm(2) area), regional perfusion was not significantly altered after TMR, and NADH fluorescence was observed throughout the ischemic region without significant spatial variation. High-resolution analysis (2.8 mg, 1 mm x 1 mm) revealed that the flow after TMR was lower, and NADH fluorescence was higher in the regions close to the channels (1-2 mm) than in the regions 3-4 mm away from them. Creating TMR channels did not improve the regional perfusion and rather aggravated the local ischemia in the vicinity of the channels in the immediate phase.     

Intercellular adhesion molecule-5 induces dendritic outgrowth by homophilic adhesion

Intercellular adhesion molecule-5 (ICAM-5) is a dendritically polarized membrane glycoprotein in telencephalic neurons, which shows heterophilic binding to leukocyte beta(2)-integrins. Here, we show that the human ICAM-5 protein interacts in a homophilic manner through the binding of the immunoglobulin domain 1 to domains 4-5. Surface coated ICAM-5-Fc promoted dendritic outgrowth and arborization of ICAM- 5-expressing hippocampal neurons. During dendritogenesis in developing rat brain, ICAM-5 was in monomer form, whereas in mature neurons it migrated as a high molecular weight complex. The findings indicate that its homophilic binding activity was regulated by nonmonomer/monomer transition. Thus, ICAM-5 displays two types of adhesion activity, homophilic binding between neurons and heterophilic binding between neurons and leukocytes.