Functional outcome after facial allograft transplantation in rats.

BACKGROUND: Full face, hemiface and facial subunit transplants have been reported before. However, the functional recovery of the face transplant largely remains unknown. The mystacial pad (also known as the vibrissal or whiskers region) is the main sensorimotor unit in rats' faces. We included the mystacial region in the hemifacial flap of the rat, and our aim was to study its functional recovery after transplant. METHODS: Hemifacial flaps were transplanted from Brown-Norway RT(n) to Wistar-Lewis RT(l) rats, under tapered doses of tacrolimus immunosuppression monotherapy (8 mg/Kg/day to 2mg/Kg/day after 4 weeks). Group I (n=12) was the anatomic study group, in which the harvesting technique of the flap was trial run and angiographies of the flap were obtained. In group II (n=12), non-vascularized hemifacial allografts were transplanted. Group III (n=24) was the vascularized hemiface allotransplant group. This was divided into two subgroups relating to nerve repairs. In subgroup III(a) (n=12) no nerve repairs were performed, while in subgroup III(b) (n=12) the zygomaticoorbital, bucolabial and upper marginal mandibular branches of the facial nerve, and the infraorbital branch of the trigeminal nerve were repaired. Clinical, neurophysiological and histological studies were performed to evaluate the recovery of the mystacial region after six weeks. RESULTS: In group I the hemifacial flap harvesting technique to include the mystacial region was established, and angiographies confirmed a rich axial vascular network in the flaps. All grafts in group II necrosed. In group III, each procedure required an average of 7h (range 5-11). Of this group, 75% of the rats survived for 8 weeks. In subgroup III(a) no signs of recovery were noted, whilst in subgroup III(b) clinical, neurophysiological and histological recovery were found in face transplant recipients after 6 weeks. CONCLUSIONS: The hemifacial flap including the mystacial region could be transplanted successfully in the rat model. Face allotransplants in which nerves were repaired showed clinical, neurophysiological and histological signs of recovery.

Influence of mannose-binding lectin on HIV infection and tuberculosis in a Western-European population.

Mannose-binding lectin (MBL) is a serum lectin that mediates phagocytosis and activates complement. Its deficiency has been associated with increased susceptibility to infectious diseases, mainly in childhood. However, non-producer mbl-2 alleles are common in most populations, suggesting a selective advantage of these alleles. We have analysed the association of mbl-2 structural and promoter polymorphisms with HIV infection and tuberculosis (TBC) in a white Spanish population, including 615 HIV patients with and without TBC, 127 no-HIV TBC patients, 142 TBC household contacts and 344 controls. The frequency of low or non-producer mbl-2 genotypes was lower in HIV patients than in controls. HIV-TBC patients presented lower frequencies of low or non-producer alleles and genotypes than HIV no-TBC patients and controls. Additionally, we found a significantly positive correlation between the incidence of TBC and the frequency of non-producer mbl-2 alleles in Western Europe. Therefore, MBL deficiency may be associated with a lower risk of HIV infection, and also of active TBC, at least in HIV patients. The protective role of low-producer mbl-2 genotypes against TBC together with the positive correlation observed between non-producer mbl-2 alleles and TBC incidence, suggest a balancing selection: in spite of an increased susceptibility to respiratory infections associated with MBL deficiency, mbl-2 deficient alleles would have been selected along different populations as a consequence of its selective advantage against intracellular pathogens, such as M. tuberculosis.

Relevance of renin expression by real-time PCR in acute myeloid leukemia.

The search for useful molecular markers in the diagnosis of AML and in the follow-up of minimal residual disease (MRD) has been the focus of many recent studies. Previous research showed that, while normal bone marrow cells lack expression of renin, myeloid blasts have been reported to do so. The aim was to study the expression of the renin gene by the use of real-time quantitative PCR (RQ-PCR) at diagnosis in acute myeloid leukemia patients (AML) and to assess its possible relevance in the prognosis and outcome of such patients. This study analysed 76 samples from patients with AML, with follow-up of positive patients. Thirty-one patients (41%) were positive for renin gene expression at diagnosis. All renin-positive patients at diagnosis showed no expression during complete remission (CR), but expression recurred in those experiencing relapse and persisted when the disease was refractory to treatment. Although the results suggest that the sub-group of renin-positive AML patients might have a worse outcome and a higher relapse rate (at 5 years, the projected rate of disease-free survival was 18.5 +/- 9.8% for renin-positive and 23.5 +/- 8.8% for renin-negative patients), no significant differences were found. It is believed that further studies should aim to validate whether such a difference exists, using a much larger and homogeneus group of patients.

Allelic variants of the human scavenger receptor class B type 1 and paraoxonase 1 on coronary heart disease: genotype-phenotype correlations.

OBJECTIVE: The antioxidant properties of high-density lipoprotein (HDL) have been attributed to paraoxonase (PON) enzyme activity. Human scavenger receptor class B type 1 (SR-BI; CD36 and lysosomal integral membrane protein-II analogous-1 [CLA-1]) plays a central role in HDL-mediated native and oxidized cholesteryl ester uptake. We tested for a significant contribution of common variant of these genes to coronary heart disease (CHD) risk and hypothesized that genetic-mediated PON activity and CLA-1/SR-BI receptor functional properties jointly reduce plasma oxidation status. METHODS AND RESULTS: We studied 304 cases and 315 controls. Polymorphisms were analyzed by polymerase chain reaction-restriction fragment analysis. CLA-1/SR-BI-relative expression levels and mRNA stability were analyzed by the comparative threshold cycle method. There was a significant difference in the male genotype distribution of the CLA-1/SR-BI exon 8 (C8/T8) variant between groups with an odds ratio of 1.7 (95% CI, 1.16 to 2.51). This significant risk was restricted to those subject carriers of Arg (R) and Leu (L) allele of the PON1 192 and 55 variants and was confirmed in multiple logistic regression analysis. CLA-1/SR-BI mRNA expression levels differed according to CLA-1/SR-BI genotypes. CONCLUSIONS: These data suggest a plausible genetic interaction between the CLA-1 exon 8 gene polymorphism and the risk of CHD in males.