980 resultados para sponge, luciferase, cloning, Suberites
Resumo:
We asked whether locally applied recombinant-Bone Morphogenic Protein-2 (rh-BMP-2) with an absorbable Type I collagen sponge (ACS) carrier could enhance the consolidation phase in a callotasis model. We performed unilateral transverse osteotomy of the tibia in 21 immature male rabbits. After a latency period of 7 days, a 3-weeks distraction was begun at a rate of 0.5mm/12h. At the end of the distraction period (Day 28) animals were randomly divided into three groups and underwent a second surgical procedure: 6 rabbits in Group I (Control group; the callus was exposed and nothing was added), 6 rabbits in Group II (ACS group; receiving the absorbable collagen sponge soaked with saline) and 9 rabbits in Group III (rh-BMP-2/ACS group; receiving the ACS soaked with 100μg/kg of rh-BMP-2, Inductos(®), Medtronic). Starting at Day 28 we assessed quantitative and qualitative radiographic parameters as well as densitometric parameters every two weeks (Days 28, 42, 56, 70 and 84). Animals were sacrificed after 8 weeks of consolidation (Day 84). Qualitative radiographic evaluation revealed hypertrophic calluses in the Group III animals. The rh-BMP-2/ACS also influenced the development of the cortex of the calluses as shown by the modified radiographic patterns in Group III when compared to Groups I and II. Densitometric analysis revealed the bone mineral content (BMC) was significantly higher in the rh-BMP-2/ACS treated animals (Group III).
Resumo:
Soluble MHC-peptide (pMHC) complexes, commonly referred to as tetramers, are widely used to enumerate and to isolate Ag-specific CD8(+) CTL. It has been noted that such complexes, as well as microsphere- or cell-associated pMHC molecules compromise the functional integrity of CTL, e.g., by inducing apoptosis of CTL, which limits their usefulness for T cell sorting or cloning. By testing well-defined soluble pMHC complexes containing linkers of different length and valence, we find that complexes comprising short linkers (i.e., short pMHC-pMHC distances), but not those containing long linkers, induce rapid death of CTL. This cell death relies on CTL activation, the coreceptor CD8 and cytoskeleton integrity, but is not dependent on death receptors (i.e., Fas, TNFR1, and TRAILR2) or caspases. Within minutes of CTL exposure to pMHC complexes, reactive oxygen species emerged and mitochondrial membrane depolarized, which is reminiscent of caspase-independent T cell death. The morphological changes induced during this rapid CTL death are characteristic of programmed necrosis and not apoptosis. Thus, soluble pMHC complexes containing long linkers are recommended to prevent T cell death, whereas those containing short linkers can be used to eliminate Ag-specific CTL.
Resumo:
The gene encoding type I signal peptidase (Lmjsp) has been cloned from Leishmania major. Lmjsp encodes a protein of 180 amino residues with a predicted molecular mass of 20.5 kDa. Comparison of the protein sequence with those of known type I signal peptidases indicates homology in five conserved domains A-E which are known to be important, or essential, for catalytic activity. Southern blot hybridisation analysis indicates that there is a single copy of the Lmjsp gene. A recombinant SPase protein and a synthetic peptide of the L. major signal peptidase were used to examine the presence of specific antibodies in sera from either recovered or active individuals of both cutaneous and visceral leishmaniasis. This evaluation demonstrated that sera from cutaneous and visceral forms of leishmaniasis are highly reactive to both the recombinant and synthetic signal peptidase antigens. Therefore, the Leishmania signal peptidase, albeit localised intracellularly, is a significant target of the Leishmania specific immune response and highlights its potential use for serodiagnosis of cutaneous and visceral leishmaniasis.
Resumo:
Secreted proteases constitute potential virulence factors of dermatophytes. A total of seven genes encoding putative serine proteases of the subtilisin family (SUB) were isolated in Trichophyton rubrum. Based on sequence data and intron-exon structure, a phylogenetic analysis of subtilisins from T. rubrum and other fungi revealed a presumed ancestral lineage comprising T. rubrum SUB2 and Aspergillus SUBs. All other SUBs (SUB1, SUB3-7) are dermatophyte-specific and have apparently emerged more recently, through successive gene duplication events. We showed that two subtilisins, Sub3 and Sub4, were detected in culture supernatants of T. rubrum grown in a medium containing soy protein as a sole nitrogen source. Both recombinant enzymes produced in Pichia pastoris are highly active on keratin azure suggesting that these proteases play an important role in invasion of keratinised tissues by the fungus. The set of deduced amino acid sequences of T. rubrum SUB ORFs allowed the identification of orthologous Subs secreted by other dermatophyte species using proteolysis and mass spectrometry.
Resumo:
Objective To verify the effect of bathing on the body temperature of preterm infants (PTI). Method Systematic review conducted in the following bibliographic electronic sources: Biblioteca Virtual em Saúde/Lilacs (BVS), Cumulated Index of Nursing and Allied Health Literature (CINAHL), Cochrane Library, Google Scholar, PubMed, SCOPUS and Web of Science, using a combination of search terms, keywords and free terms. The review question was adjusted to the PICO acronym (Patient/population, Intervention, Control/comparative intervention, Outcome). The selected publications were evaluated according to levels of evidence and grades of recommendation for efficacy/effectiveness studies, as established by the Joanna Briggs Institute. Results Eight hundred and twenty four (824) publications were identified and four studies met the inclusion criteria, of which three analyzed the effect of sponge baths and the effect of immersion baths. Conclusion Sponge baths showed a statistically significant drop in body temperature, while in immersion baths the body temperature remained stable, although they studied late preterm infants.