Deficiency or inhibition of Gas6 causes platelet dysfunction and protects mice against thrombosis.

The growth arrest-specific gene 6 product (Gas6) is a secreted protein related to the anticoagulant protein S but its role in hemostasis is unknown. Here we show that inactivation of the Gas6 gene prevented venous and arterial thrombosis in mice, and protected against fatal collagen/epinephrine-induced thrombo embolism. Gas6-/- mice did not, however, suffer spontaneous bleeding and had normal bleeding after tail clipping.

[Allergy to cypress pollen: preparation of a reference and standardization extract in vivo].

Development of Cypress allergy frequency led to the standardization of commercial cypress extract used for diagnosis and immunotherapy. Previous in vitro studies on two cypress pollen species (Cupressus sempervirens and Cupressus arizonica) allowed us to produce an allergenic solution composed by a mixture of both extracts for in vivo standardization. Dilutions of this allergenic solution were tested by prick-test on 44 patients with clinical allergy to cypress pollen to define the dilution that corresponds to a 6 mm wheal conformed to the definition of 100 IR.

Age- and disease-related decline in immune function: an opportunity for "thymus-boosting" therapies.

The thymus is the site of production of mature T lymphocytes and thus is indispensable for the development and maintenance of the T cell-mediated arm of the immune system. Thymic production of mature T cells is critically dependent on an influx of bone marrow-derived progenitor T cells that undergo replication and selection within the thymus. Thymus cellularity and thymic hormone secretion reach a peak during the first year of life and then decline gradually until the age of 50-60 years, a process known as "thymic involution.

The barrier choice paradigm: haloperidol reduces sensitivity to reinforcement.

The standard choice situation was modified by placing a 76 cm high barrier between two levers. To travel between levers, rats had to climb the barrier. Four doses of haloperidol were assessed for effects on motor and motivational systems.

Relationship between contact time measurements and PTV values when using the Periotest to measure implant stability.

Purpose: The Periotest is an electronic instrument that has been advocated for the measurement of implant stability and osseointegration. The aims of this investigation were to establish the relationship between contact time and PTV values when the Periotest was used to assess implants in vivo and in vitro, and to investigate the influence of the striking height of the Periotest handpiece and the length of implant abutment.

Materials And Methods: The accelerometer signal from a Periotest was captured and compared with the resulting PTV value.

Correction for label leakage in fluorimetric assays of cell adhesion.

Current fluorescence-based adhesion assays that use a 96-well plate format rely on the assumption that the fluorescent label does not significantly leak from the cells. Thus, we evaluated a calcein-based, in vitro adhesion assay in 96-well plates using five different types of leukocytes (HL60 cells, human neutrophils, rat neutrophils, mouse progenitor T cells and EL4 cells). Each cell type leaked calcein at a different rate, with the highest rates found for rat neutrophils and progenitor T cells, which lost as much as 20%-40% of the label within 90 min, the time required to complete the assay.

The use of the Periotest value as the initial success criteria of an implant: 8-year report.

Osseointegration is a histometric process that occurs gradually over a period of time. The load that an implant is able to bear depends upon, among other parameters, the quality of the bone-implant contact. For 8 years the damping capacity of 1,182 Brånemark implants inserted consecutively in 315 patients was measured using the Periotest method.

Tumor necrosis factor-alpha (TNF-alpha) induces a reversible, time- and dose-dependent adhesion of progenitor T cells to endothelial cells.

Recent in vivo studies suggest that tumor necrosis factor-alpha (TNF-alpha) is involved in the development of the thymus. We postulated that this inflammatory mediator could regulate the influx of progenitor T cells into the thymus. Using an in vitro static adhesion system, we found that TNF-alpha increases the adhesion of a murine progenitor T cell line (FTF1) to a bovine aortic endothelial cell line (1F8), human umbilical vein endothelial (HUVE) cells, and a murine arterial endothelial (MAE) cell line.

Molecular mechanisms of activated protein C resistance. Properties of factor V isolated from an individual with homozygosity for the Arg506 to Gln mutation in the factor V gene.

Resistance to activated protein C (APC), which is the most prevalent pathogenetic risk factor of thrombosis, is linked to a single point-mutation in the factor V (FV) gene, which predicts replacement of Arg (R) at position 506 with a Gln (Q). This mutation modifies one of three APC-cleavage sites in the heavy chain of activated FV (FVa), suggesting that mutated FVa (FVa:Q506) is at least partially resistant to APC-mediated degradation. To elucidate the molecular mechanisms of APC-resistance and to investigate the functional properties of FV in APC resistance, FV:Q506 was purified from an individual with homozygosity for the Arg to Gln mutation.

A new method for achieving passive fit of an interim restoration supported by Brånemark implants: a technical note.

When carrying out restorations supported by dental implants, it is advisable to have a temporary method that offers the possibility of evaluating and/or creating a proper emergence profile, peri-implant health, occlusion, esthetics, acceptable phonetic response, and hygiene, as well as one that facilitates progressive loading of the implants during the bone maturation period. To maintain osseointegration it is essential that a prosthesis fit with total passivity, since the lack of a periodontal ligament renders the implant unable to modify its position. Gold cylinders for EsthetiCone abutments, which were modified following a previously reported technique, were used so that provisional prostheses could be fixed to the cylinders in the mouth by means of an alternative cementing technique.

A new method to routinely achieve passive fit of ceramometal prostheses over Brånemark osseointegrated implants: a two-year report.

To maintain osseointegration, it is essential that the prosthesis fit with total passivity because the absence of a periodontal ligament makes the implant unable to adapt its position to a nonpassive framework. The traditional system of building a metal framework by melting over mechanized pieces--called gold cylinders in the Brånemark system--has been modified so these pieces are joined to the metal framework by means of physicochemical bonding. This bond is achieved by treating the metallic surfaces with a Silicoater system and a composite resin cement that sets in the mouth using an improved cementing protocol.

[The inhalational therapy of respiratory pathology].

The inhalation of aerosolized drugs for therapeutic purpose has been used for many years in respiratory diseases as asthma, chronic bronchitis, cystic fibrosis. Therapeutic aerosols have the advantages to deliver active substances directly to the site of disease, without systemic side effects, to produce a more rapid clinical response, to avoid barriers to the absorption of drugs such as the gastrointestinal tract. We review the mechanisms and the site of lung deposition and the range of devices that can provide an effective aerosol such as metered dose-inhaler and spacers.

Comparative surface microanalysis of failed Brånemark implants.

The chemical composition and topography of an implant surface determine the human immunologic system response. This study compared the surfaces of 13 Brånemark oral implants, 11 that came from retrieved specimens which failed initially or did not osseointegrate and 2 that were never implanted (controls). The period of implantation in human jaws varied between 3 and 20 months.

Relationship between tryptophan biosynthesis and indole-3-acetic acid production in Azospirillum: identification and sequencing of a trpGDC cluster.

Screening the tryptophan (Trp)-dependent indole-3-acetic acid (IAA) production of different Azospirillum species revealed that A. irakense KA3 released 10 times less IAA into the medium than A. brasilense Sp7.

Expression of catalytically active radish 3-hydroxy-3-methylglutaryl coenzyme A reductase in Escherichia coli.

Two fragments of a cDNA encoding radish 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) were cloned into the vector pET-8c and expressed in Escherichia coli. The large fragment, encoding both the membrane and the cytosolic domains, was expressed at low level, essentially as an insoluble protein without enzymatic activity. In contrast, the fragment encoding only the cytosolic domain was expressed at a high level in a catalytically active form.

Periotest method as a measure of osseointegrated oral implant stability.

Oral implant stability is essential for optimal function. Results obtained from the Periotest measurement of the stability of 204 commercially pure titanium implants, consecutively placed in 22 maxillae and 24 mandibles according to the Brånemark procedure, are reported. Preliminary results suggest that the Periotest value of an oral implant is an objective and easily applied criterion for stability assessment.

Characterization of surface roughness in titanium dental implants measured with scanning tunnelling microscopy at atmospheric pressure.

Characterization of the surface topography of implant materials is important for understanding tissue response. We have measured, for the first time, the topography of titanium surfaces used in osseointegrated dental implants. Scanning tunnelling microscopy (STM) which provides 3D real space images was used.