Genetic polymorphisms of the T-cell coreceptors CD28 and CTLA-4 in Afro- and Euro-Brazilians.

CD28 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) are two receptors that have complementary functions in control of T-cell activation. Polymorphisms of their genes, CD28 and CTLA4, might confer differential susceptibility to diseases resulting from unbalanced or inefficient immune responses. Thus far, little is known about the CD28 polymorphism in populations and even for CTLA4 just one or two single nucleotide polymorphisms (SNPs) are usually analysed. To assess the allelic and haplotypic diversity and linkage disequilibrium in the Brazilian population, two samples differing according to predominant ancestry - African or European - have been analysed for seven SNPs, CD28 -372(G>A), and int3 17(T>C); CTLA4 -1722(T>C), -1577(G>A) -318(C>T), 49(A>G), 6230(G>A) also named CT60, and three microsatellites, CD28 (CAA)n, CTLA4 (AT)n and D2S72 (CA)n. The two population strata show little differentiation, the only significant differences being the allele frequencies of the CTLA4 -1577(G>A) SNP and the CTLA4 (AT)n microsatellite (P = 0.018 and P = 0.007, respectively). Linkage disequilibrium is high, especially between the CTLA4 polymorphisms. However, low r(2) values indicate that none of the markers is a tag SNP in these populations. These results provide valuable information for optimal selection of markers for use in future association studies. We conclude that disease association studies and functional studies addressing the possible consequences of polymorphisms of the 2q33 genomic region should consider haplotypic data besides analysis of individual polymorphisms.

Cord blood (CB) stem cells for wound repair. Preliminary report of 2 cases.

In 2 patients, to promote skin wound/lesion repair we used fibrin-platelet glue combined with HLA compatible (2 mismatches accepted) buffy coats containing CD 34+ cord blood cells. The fibrin platelet glue was prepared with autologous apheresis platelets and cryoprecipitate. The original product was divided into 3 and 4 aliquots respectively for a correspondent number of applications. At each application, the margins of the lesion were infiltrated with 3 ml of cord blood buffy coat, containing 30 x 10(3) CD 34+ cells. No graft versus tissue reaction was seen in our patients in a follow-up of 3-7 months. The level of improvement, scored arbitrarily from 0 to 4, was 3 and 4, respectively. Our conclusion is that the use of cord blood cells along with fibrin platelet glue is of clinical interest.

The role of autologous fibrin-platelet glue in plastic surgery: a preliminary report.

To promote wound healing, we used autologous fibrin-platelet glue in 14 patients with skin and soft tissue losses caused by recent trauma or chronic pathology. The level of improvement was scored, arbitrarily, from 0 to 4. Very favourable results (score 3-4) were seen in 11 out of 14 patients. The glue preparation is very easy, inexpensive and creates excellent and stable hemostasis. From a general point of view, we have confirmed the utility of fibrin-platelet glue in terms of reduced infections and length of hospital stay.

In vitro antimicrobial effects of fresh split skin, homologous-cultured epithelium and porcine split skin grafts for wound coverage.

Various biological dressings, for example, human fresh and cadaver skin grafts, homologous cultured human epithelium and deep frozen porcine split skin (Lyocutis), have been used to treat skin loss. Each of these biological dressings has its advantages and disadvantages. The antimicrobial properties of each dressing type are important since bactericidal activity influences the lifespan of the transplanted tissue. In the present study the in vitro antimicrobial effects of human fresh skin, homologous cultured epithelium and Lyocutis were compared to in vivo bactericidal activity of these dressings and possible clinical applications are recommended.

[Amikacin in the topical treatment of small losses of substance]. / L'amikacina nel trattamento topico di piccole perdite di sostanza.

The paper describes the use of aminoglucoside amikacin over 3 years in a group of 187 patients for the topical treatment of skin lesions extending over a maximum 10% of body surface area. The use of amikacin for topical treatment was chosen on the basis of clinical factors; in the majority of cases these were associated to poor circulation in the affected region which created uncertainty as to whether an efficacious dose would be provided by intravenous administration.