Lab-on-a-chip for multiplexed biosensing of residual antibiotics in milk.

A multiplexed immunoassay-based antibiotic sensing device integrated in a lab-on-a-chip format is described. The approach is multidisciplinary and involves the convergent development of a multi-antibiotic competitive immunoassay based on sensitive wavelength interrogated optical sensor (WIOS) technology and a polymer-based self-contained microfluidic cartridge. Immunoassay solutions are pressure-driven through external and concerted actuation of a single syringe pump and multiposition valve.

Phospholipase A2-activating protein (PLAA) enhances cisplatin-induced apoptosis in HeLa cells.

Phospholipase A(2) (PLA(2))-activating protein (PLAA) is a novel signaling molecule that regulates eicosanoid production and participates in inflammatory responses. In our current study, we revealed that PLAA production was induced by the chemotherapeutic drug cisplatin in HeLa cervical carcinoma cells. To determine the potential pro-apoptotic effects of PLAA induction by cisplatin, we utilized HeLa (Tet-off) cells overexpressing the plaa gene (plaa(high)) and compared them with control (plaa(low)) cells, which produce endogenous plaa from the chromosome.

Genetic diversity and spatial genetic structure within a population of an aromatic shrub, Lippia origanoides (Verbenaceae), in the Chicamocha Canyon, northeastern Colombia.

The geographical scale of genetic structure in a continuous population is highly dependent on its breeding system and dispersion capabilities, and this knowledge is important for the study of population dynamics as well as for conservation purposes. In the present study, spatial autocorrelation statistics and intersimple sequence repeat (ISSR) markers were used to describe the genetic structure of a natural population of a prominent aromatic plant, Lippia origanoides, native to the Chicamocha Canyon in northeastern Colombia. For this purpose, individuals were sampled from two localities within the Chicamocha Canyon, where the species is abundant and continuously distributed.

Characterization of the rat pneumonic plague model: infection kinetics following aerosolization of Yersinia pestis CO92.

Yersinia pestis, the causative agent of human bubonic and pneumonic plague, is spread during natural infection by the fleas of rodents. Historically associated with infected rat fleas, studies on the kinetics of infection in rats are surprisingly few, and these reports have focused mainly on bubonic plague. Although the natural route of primary infection results in bubonic plague in humans, it is commonly thought that aerosolized Y.

Spectroscopic and theoretical study of 2-acetylphenyl-2-naphthoate.

Mid-, far-infrared and Raman vibrational spectra of 2-acetylphenyl-2-naphthoate have been measured at room and low temperatures. The molecule was also analyzed by means of ab initio calculations. The conformational space has been scanned using molecular dynamics and complemented with functional density calculations that optimize the geometry of the lowest energy conformers 2-acetylphenyl-2-naphthoate as obtained in the simulations.

Effect of position on valsalva maneuver: supine versus 20 degree position.

Blood pressure changes in response to the Valsalva maneuver (VM), which reflect the integrity of the baroreflex that regulates blood pressure. Performing this maneuver in the standard supine position often prevents adequate venous preload reduction, resulting in a rise rather than a fall in blood pressure, the "flat-top" Valsalva response. We determined whether performing the VM at a 20 degree angle of head-up tilt (20 degrees ) improves preload reduction, thereby reducing the frequency of flat-top responses, improving reflex vasoconstriction, and increasing the Valsalva ratio.

The impact of acute lymphoblastic leukemia treatment on central nervous system results in Bogota, Colombia.

To improve the outcome of children with acute lymphoblastic leukemia (ALL) treated at the National Cancer Institute, Bogota, Colombia, a protocol based on the BFM-90 (Berlin, Frankfurt, Munster study) and the LSA2L2 regimens was implemented in the year 1993. The patients were classified as being standard risk (SR) or high risk (HR) according to clinical criteria, to which cytogenetic information and day-8 prednisone response were also added. A 123-patient cohort entered the study, 18 of them being considered SR and 105 HR.

Characterization of a mouse model of plague after aerosolization of Yersinia pestis CO92.

Yersinia pestis is a Gram-negative bacterium, and the causative agent of bubonic plague and pneumonic plague. Because of its potential use as a biological warfare weapon, the plague bacterium has been placed on the list of category A select agents. The dynamics of pneumonic infection following aerosolization of the highly virulent Y.

Neurotoxic envenoming by South American coral snake (Micrurus lemniscatus helleri): case report from eastern Ecuador and review.

A man bitten by a large coral snake (Micrurus lemniscatus helleri) in the Amazon basin of Ecuador developed persistent excruciating pain in the bitten arm. On admission to hospital less than 30 min later, he had a polymorphonuclear leucocytosis, thrombocytopenia and mildly prolonged prothrombin time/partial thromboplastin time. Not until 14 h after the bite did he develop the first signs of neurotoxicity.

Alteration in the activation state of new inflammation-associated targets by phospholipase A2-activating protein (PLAA).

Phospholipase A(2) (PLA(2))-activating protein (PLAA) is a novel signaling molecule that regulates the production of prostaglandins (PGE(2)) and tumor necrosis factor (TNF)-alpha. To characterize the function of native PLAA in situ, we generated HeLa (Tet-off) cells overexpressing plaa (plaa(high)) and control (plaa(low)) cells, with the plaa gene in opposite orientation in the latter construct. The plaa(high) cells produced significantly more PGE(2) and interleukin (IL)-6 compared to plaa(low) cells in response to TNF-alpha.

Braun lipoprotein (Lpp) contributes to virulence of yersiniae: potential role of Lpp in inducing bubonic and pneumonic plague.

Yersinia pestis evolved from Y. pseudotuberculosis to become the causative agent of bubonic and pneumonic plague. We identified a homolog of the Salmonella enterica serovar Typhimurium lipoprotein (lpp) gene in Yersinia species and prepared lpp gene deletion mutants of Y.

Three 4,7-diaryl-2-ethylsulfanylpyrazolo[1,5-a][1,3,5]triazines.

The molecular dimensions of 2-ethylsulfanyl-7-(4-methylphenyl)-4-phenylpyrazolo[1,5-a][1,3,5]triazine, C20H18N4S, (I), 7-(4-chlorophenyl)-2-ethylsulfanyl-4-phenylpyrazolo[1,5-a][1,3,5]triazine, C19H15ClN4S, (II), and 4,7-bis(4-chlorophenyl)-2-(ethylsulfanyl)pyrazolo[1,5-a][1,3,5]triazine, C19H14Cl2N4S, (III), show evidence for some aromatic delocalization in the pyrazole rings. The conformations adopted by the ethylsulfanyl substituents are different in all three compounds. There are no hydrogen bonds in any of the crystal structures, but pairs of molecules in (II) and (III) are linked into centrosymmetric dimers by pi-stacking interactions.

Transcriptional profiling of murine organ genes in response to infection with Bacillus anthracis Ames spores.

Bacillus anthracis is the Gram-positive, spore-forming etiological agent of anthrax, an affliction studied because of its importance as a potential bioweapon. Although in vitro transcriptional responses of macrophages to either spore or anthrax toxins have been previously reported, little is known regarding the impact of infection on gene expression in host tissues. We infected Swiss-Webster mice intranasally with 5 LD(50) of B.

Molecular characterization of a functional type VI secretion system from a clinical isolate of Aeromonas hydrophila.

Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrophila infections was subsequently delineated in in vitro and in vivo models.

Nanoscale energy deposition by X-ray absorbing nanostructures.

Here we wish to demonstrate a unique property of nanomaterials: energy deposition with nanometer precision from low-energy electrons released from these nanostructures interacting with hard X-ray radiation in aqueous solution. Three effects combine to cause this phenomenon: (1) localized absorption of X-rays by nanostructures, (2) effective release of low-energy electrons from small nanostructures, and (3) efficient deposition of energy in water in the form of radicals and electrons. This combination creates localized X-ray absorption and localized energy deposition of nanometer precision.

A randomized, investigator-blinded, time-ranging study of the comparative efficacy of 0.5% malathion gel versus Ovide Lotion (0.5% malathion) or Nix Crème Rinse (1% permethrin) used as labeled, for the treatment of head lice.

One hundred seventy-two subjects with head lice participated in a five-way, investigator-blinded, parallel-group, active-controlled study comparing 0.5% malathion gel (30, 60, and 90 minutes applications), Ovide Lotion (0.5% malathion), and Nix Crème Rinse (1% permethrin).

Further characterization of a type III secretion system (T3SS) and of a new effector protein from a clinical isolate of Aeromonas hydrophila--part I.

A type III secretion system (T3SS)-associated cytotoxin, AexT, with ADP-ribosyltransferase activity and homology to Pseudomonas aeruginosa bifuncational toxins ExoT/S, was recently identified from a fish pathogen Aeromonas salmonicida. In this study, we reported the molecular characterization of an aexT-like toxin gene (designated as aexU) from a diarrheal isolate SSU of A. hydrophila.

Biological characterization of a new type III secretion system effector from a clinical isolate of Aeromonas hydrophila-part II.

We recently identified a novel type III secretion system (T3SS) effector, AexU, from a diarrheal isolate SSU of Aeromonas hydrophila, and demonstrated that mice infected with the DeltaaexU mutant were significantly protected from mortality. Although the NH(2)-terminal domain of this toxin exhibits homology to AexT of A. salmonicida, a fish pathogen, and ExoT/S of Pseudomonas aeruginosa, the COOH-terminal domain of AexU is unique, with no homology to any known proteins in the NCBI database.

Monocyte chemoattractant protein-1 production by intestinal myofibroblasts in response to staphylococcal enterotoxin a: relevance to staphylococcal enterotoxigenic disease.

Food poisoning due to staphylococcal enterotoxins A and B (SEA and SEB) affects hundreds of thousands of people annually. SEA and SEB induce massive intestinal cytokine production, which is believed to be the key factor in staphylococcal enterotoxin enteropathy. MHC class II molecules are the major receptors for staphylococcal enterotoxins.

Effect of cigarette smoking on the oxidant/antioxidant balance in healthy subjects.

Background And Purpose: Cigarette smoking has been associated with the development of cardiovascular disease and cancer. Even though the molecular mechanism(s) are not clear, the pathology has been related to oxygen free radicals present in cigarette smoke. Thus, the main objective of this study was to establish the changes in the oxidation/antioxidation balance induced by cigarette smoking.

Chemical introduction of disulfide groups on glycoproteins: a direct protein anchoring scenario.

The present work reports a direct glycoprotein immobilization protocol where the protein is chemically modified with disulfide groups which act as anchor molecules able to chemisorb spontaneously onto clean gold surfaces. The specificity of the chemical reaction, for disulfide introduction, toward carbohydrate moieties prevents any cross-reaction with other functional groups present in the protein structure. Horseradish peroxidase (HRP) was chosen as a model glycoprotein, and a biologically active densely packed SAM was obtained on gold, as demonstrated by spectrophotometry and surface plasmon resonance (SPR) spectroscopy.

Subepithelial myofibroblasts are novel nonprofessional APCs in the human colonic mucosa.

The human gastrointestinal mucosa is exposed to a diverse normal microflora and dietary Ags and is a common site of entry for pathogens. The mucosal immune system must respond to these diverse signals with either the initiation of immunity or tolerance. APCs are important accessory cells that modulate T cell responses which initiate and maintain adaptive immunity.