Density-Dependent Prevalence of Francisella tularensis in Fluctuating Vole Populations, Northwestern Spain.

Tularemia in humans in northwestern Spain is associated with increases in vole populations. Prevalence of infection with Francisella tularensis in common voles increased to 33% during a vole population fluctuation. This finding confirms that voles are spillover agents for zoonotic outbreaks.

Synergistic divergence: a distinct ocular motility dysinnervation pattern.

Purpose: To summarize the clinical, neuroradiologic, and genetic observations in a group of patients with unilateral synergistic divergence (SD).

Methods: Five unrelated patients with unilateral SD underwent ophthalmic and orthoptic examinations; three of them also had magnetic resonance imaging of the brain and orbits. Three patients underwent genetic evaluation of genes known to affect ocular motility: KIF21A, PHOX2A, HOXA1, and ROBO3.

Gauze retrieval of probes in pediatric nasolacrimal intubation.

The authors describe a novel technique that facilitates retrieval of lacrimal probes from the nasal fossa during silicone intubation of the lacrimal drainage system in children. Gauze preplaced in the nasal fossa is used to retrieve the lacrimal intubation probes with no need for visual or mechanical identification of the probe intranasally.

Scleral thinning after transcleral diode laser cycloablation.

Background And Objective: To highlight the occurrence of scleral thinning after transcleral diode laser cycloablation therapy.

Patients And Methods: A retrospective chart review was done of consecutive patients from the glaucoma and pediatric ophthalmology clinics of a tertiary eye care center in whom the presence of scleral thinning was noted after transcleral diode laser cycloablation therapy.

Results: Eleven eyes of 9 patients with various types of glaucoma (traumatic, congenital, juvenile, steroid induced, uveitic, and secondary angle closure) were found to have scleral thinning after undergoing transcleral diode laser cycloablation therapy for refractory glaucoma.

DNA immunisation with minimalistic expression constructs.

The low efficacy obtained in large animals makes plasmid-based DNA vaccines commercially unviable. Another concern is the presence of antibiotic resistance markers on virtually all conventional plasmids. Here we describe the use of minimalistic, immunogenically defined gene expression (MIDGE) vectors for DNA vaccination.

Blocking HIV-1 infection via CCR5 and CXCR4 receptors by acting in trans on the CCR2 chemokine receptor.

The identification of chemokine receptors as HIV-1 coreceptors has focused research on developing strategies to prevent HIV-1 infection. We generated CCR2-01, a CCR2 receptor-specific monoclonal antibody that neither competes with the chemokine CCL2 for binding nor triggers signaling, but nonetheless blocks replication of monotropic (R5) and T-tropic (X4) HIV-1 strains. This effect is explained by the ability of CCR2-01 to induce oligomerization of CCR2 with the CCR5 or CXCR4 viral coreceptors.

DNA vaccination with linear minimalistic (MIDGE) vectors confers protection against Leishmania major infection in mice.

Immunization protocols based on priming with plasmid DNA and boosting with recombinants of vaccinia virus (rVV) encoding the same antigen offer great promise for the prevention and treatment of many parasitic and viral infections for which conventional vaccination has little or no effect. To overcome some of the potential problems associated to the use of plasmids, we have developed minimalistic, immunogenically defined, gene expression (MIDGE((R))) vectors. These linear vectors contain only the minimum sequence required for gene expression and can be chemically modified to increase the immune response.

Functional inactivation of CXC chemokine receptor 4-mediated responses through SOCS3 up-regulation.

Hematopoietic cell growth, differentiation, and chemotactic responses require coordinated action between cytokines and chemokines. Cytokines promote receptor oligomerization, followed by Janus kinase (JAK) kinase activation, signal transducers and transactivators of transcription (STAT) nuclear translocation, and transcription of cytokine-responsive genes. These include genes that encode a family of negative regulators of cytokine signaling, the suppressors of cytokine signaling (SOCS) proteins.

Receptor dimerization: a key step in chemokine signaling.

Chemokines exert their effects through their interaction with seven transmembrane domain receptors coupled to G-proteins, GPCRs. Such receptor ligation leads to the regulation of numerous activities where chemokines play a key role, including hematopoiesis, T-cell activation, angiogenesis, inflammatory diseases or HIV-1 infection. Here we discuss the molecular mechanisms that underlie chemokine receptor activation.

Chemokine receptor homo- or heterodimerization activates distinct signaling pathways.

Chemokine receptors of both the CC and CXC families have been demonstrated to undergo a ligand-mediated homodimerization process required for Ca2+ flux and chemotaxis. We show that, in the chemokine response, heterodimerization is also permitted between given receptor pairs, specifically between CCR2 and CCR5. This has functional consequences, as the CCR2 and CCR5 ligands monocyte chemotactic protein-1 (MCP-1) and RANTES (regulated upon activation, normal T cell-expressed and secreted) cooperate to trigger calcium responses at concentrations 10- to 100-fold lower than the threshold for either chemokine alone.

HIV-1 infection through the CCR5 receptor is blocked by receptor dimerization.

The identification of the chemokine receptors as receptors for HIV-1 has boosted interest in these molecules, raising expectations for the development of new strategies to prevent HIV-1 infection. The discovery that chemokines block HIV-1 replication has focused attention on identifying their mechanism of action. Previous studies concluded that this inhibitory effect may be mediated by steric hindrance or by receptor down-regulation.

The chemokine SDF-1alpha triggers CXCR4 receptor dimerization and activates the JAK/STAT pathway.

The chemokine stromal cell-derived factor (SDF-1alpha), the ligand for the CXCR4 receptor, induces a wide variety of effects that include calcium mobilization, chemotactic responses, bone marrow myelopoiesis, neuronal patterning, and prevention of HIV-1 infection. Nonetheless, little is known of the biochemical pathways required to achieve this variety of responses triggered after receptor-chemokine interaction. We developed a set of monoclonal antibodies that specifically recognize the CXCR4 receptor and used them to identify the signaling pathway activated after SDF-1alpha binding in human T cell lines.

Characterization of RANTES- and aminooxypentane-RANTES-triggered desensitization signals reveals differences in recruitment of the G protein-coupled receptor complex.

The trafficking of lymphocyte populations is a complex process controlled by a vast array of molecules. In this process, cells must be able to sense small changes in chemoattractant gradients. Migration through a chemotactic gradient probably employs an on-off mechanism in which chemokine receptor desensitization, internalization, and recycling may be important steps.

The chemokine monocyte chemoattractant protein-1 induces functional responses through dimerization of its receptor CCR2.

Cytokines interact with hematopoietin superfamily receptors and stimulate receptor dimerization. We demonstrate that chemoattractant cytokines (chemokines) also trigger biological responses through receptor dimerization. Functional responses are induced after pairwise crosslinking of chemokine receptors by bivalent agonistic antichemokine receptor mAb, but not by their Fab fragments.

Similarities and differences in RANTES- and (AOP)-RANTES-triggered signals: implications for chemotaxis.

Chemokines are a family of proinflammatory cytokines that attract and activate specific types of leukocytes. Chemokines mediate their effects via interaction with seven transmembrane G protein-coupled receptors (GPCR). Using CCR5-transfected HEK-293 cells, we show that both the CCR5 ligand, RANTES, as well as its derivative, aminooxypentane (AOP)- RANTES, trigger immediate responses such as Ca2+ influx, receptor dimerization, tyrosine phosphorylation, and Galphai as well as JAK/STAT association to the receptor.

The chemokine monocyte chemotactic protein 1 triggers Janus kinase 2 activation and tyrosine phosphorylation of the CCR2B receptor.

The chemokines are a growing family of low m.w., 70- to 80-residue proinflammatory cytokines that operate by interacting with G protein-coupled receptors.

Monocanalicular lacrimonasal intubation.

A new technique to obtain patency of the lacrimal drainage system was used in three children with bilateral congenital obstruction of the lacrimonasal duct (six cases) and upper canalicular abnormalities (five cases). The upper canalicular abnormalities prevented bicanaliculonasal intubation.A silicone tube was passed through the lower canaliculus, traversing the lacrimal drainage system and into the nasal fossa.

Goniotomy with sodium hyaluronate.

A modification of the classical goniotomy technique is described. After complete evacuation of the anterior and posterior chambers, sodium hyaluronate is placed in the anterior chamber and on the cornea. Putting hyaluronate in both locations prevents the formation of air bubbles under the goniotomy lens, provides the same index of refraction on both sides of the cornea, prevents accidental loss of the anterior chamber, and allows maximal depth of the anterior chamber.

Direct visualization of heterophorias through a unidirectional occluder.

A new occluder to perform the cover test allows visualization of the covered eye through the occluder and direct observation of heterophorias. The occluder is composed of an aluminium-polyester filter mounted on a support in front of a 2.2-V light bulb.

Epikeratophakia on pediatric traumatized corneas.

Four children ranging from 4 to 6 years of age with unilateral aphakia and corneal scarring secondary to penetrating injuries were treated with epikeratophakia. One child had undergone a rotational penetrating keratoplasty to displace the corneal scar from the visual axis prior to the epikeratophakia procedure. In all of the cases, nonlyophilized donor tissue was utilized.