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INTRODUCTION: Circulating endothelial progenitor cells (EPCs) may play a crucial role during pregnancy by sustaining adequate placentation and fetal growth. Unambiguous demonstration of EPC increase during pregnancy has been hampered so far by lack of standardized methods for EPC quantification. In this study we used the currently most accepted phenotype for EPC detection for investigating whether maternal circulating EPCs might increase during normal pregnancy and whether they may fail to increase in pregnancy complicated by idiopathic intrauterine growth restriction (IUGR), a leading cause of perinatal mortality and morbidity characterized by insufficient placental perfusion. METHODS: Twenty-one non-pregnant women, 44 women during healthy pregnancy progression (9, 13 and 22 women in the first, second and third trimester, respectively) and 11 with pregnancy complicated by idiopathic IUGR were recruited in a cross-sectional study. EPCs in maternal blood were identified as CD45(dim)/CD34+ / KDR+ cells by flow cytometry. Plasmatic cytokines were measured by ELISA. RESULTS: We observed a significant and progressive increase of EPCs in normal pregnancy, yet detectable in early pregnancy but even more pronounced in the third trimester. The increase of EPCs was impaired in IUGR-complicated pregnancies at comparable gestational age. The circulating levels of placental growth-factor and stromal-derived-factor-1 were significantly lower in IUGR than normal pregnancies, possibly contributing to EPC impairment. CONCLUSIONS: EPC count in maternal circulation may have a great potential as a novel biomarker for pregnancy monitoring and may represent the target of novel therapeutic strategies designed to prevent adverse pregnancy outcomes often occurring in IUGR.

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OBJECTIVES: The composite radial forearm flap is a surgical option in the reconstruction of large traumatic or oncologic orofacial defects. Nevertheless, it has been criticized for its poor bone transport faculties that would make this flap insufficient in large osseous mandibular reconstructions, or for oral prosthetic rehabilitation with dental implants. What is more, the morbidity of the donor site has often been pointed. The aim of this radioanatomic study was to revisit the vascularization of the composite radial forearm flap, focusing on the bone stick. METHODS: A radioanatomic study was performed on seven upper limbs taken from fresh cadavers. First, the vessels were washed with a 40°C solution of potassium acetate. Then an intra-arterial injection of a mixture of lead oxide and agar-agar was performed. 3D-CT-scan examinations of the anatomical pieces were performed. In a second step, the flaps were harvested and analyzed with a Microscan examination (NanoSPECT-CT Bioscan(®), voxel 220 microns). Collateral branches of the radial artery to the bone and the skin were counted and classified. RESULTS: One radial diaphyseal artery was present in all the cases. The nutrient foramen took place at the anteromedial aspect of the diaphysis, between 45 and 65 % of the length of the bone. A dense anastomotic periosteal network was highlightened, supplied by one to four musculoperiosteal branches, and one to six fascio-periosteal arteries arising from the radial artery. A total of mean five osseous branches, and 12 cutaneous branches have been observed. CONCLUSIONS: The results of the present preclinical study suggested that a 16-cm bone stick could be harvested with an optimal vascular safety, without consideration for the morbidity at the donor site. The original approach in this study, relating anatomy to the preclinical imaging, allowed a precise visualization of the microvascularization of the soft and hard tissues. It opened a field of innovative research in plastic and reconstructive surgery.

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INTRODUCTION: Maxillofacial defects often affect various type of tissues and require reconstruction using composite flaps. The radial forearm osteofasciocutaneous free flap is one of the least used. We present the preliminary results of maxillofacial reconstruction using this free flap. MATERIALS AND METHODS: We reviewed the records of patients having undergone a radial forearm osteofasciocutaneous flap procedure between 2009 and 2011. Mandibular defect were staged according to HCL classification. Maxillary defects were staged according to Cordeiro and Santamaria's classification. Functional results (swallowing and speech) were assessed at the sixth month. RESULTS: The mean age of the 10 patients was 60.2 years. The average length of bone defect was 8 cm. The average cutaneous defect area was 36.8 cm(2). The mandibular defect was LCL in six cases, L in one case, and C in one case. The two cases of maxillary bone loss were classified IIIa. Six of the 10 microsurgical anastomoses were contralateral to the lesion. There was no reconstruction failure. Three patients had mild speech disorders, five had moderate speech disorders, and two major speech disorders. Four patients had a normal food intake, three patients needed mixed food, and three patients liquid food. DISCUSSION: The indications of radial forearm osteofasciocutaneous free flap for complex maxillofacial reconstructions should be extended. Its vascularization is less compromised by arteritis. Its pedicle may be long and adequate for a contralateral anastomosis. It is reliable and easy to harvest. But the bone quality is not as good as fibula.

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Restoring blood flow to ischemic tissue is a prerequisite for treatment of ischemic diseases. Cell-based therapy based on bone marrow transplantation is a promising option for patients with critical limb ischemia (CLI). The efficacy of cell therapies to augment neovascularization seems to involve endothelial progenitor cells (EPCs); however, the mechanisms underlying the efficacy have not been fully elucidated. Herein we have described the case of a young patient with severe CLI, who experienced a 24-month beneficial clinical response to autologous bone marrow transplantation. The exceptional amelioration enabled him to perform standardized maximal treadmill exercise test that demonstrated lack of exercise-induced EPC mobilization, despite adequate stromal-derived factor 1 and vascular endothelial growth factor responses. Therefore, tissue ischemia is not sufficient to promote the recruitment of EPCs that have been demonstrated to be involved in the recovery from ischemia. The local implantation of marrow-derived elements may provide cells and/or trophic factors, which have the capacity to augment angiogenesis, opening new approaches to the etiopathogenesis of the disease.

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This study was designed to simulate purine nucleoside phosphorylase (PNP) deficiency by preincubating with guanosine (Guo) to minimize PNP activity while investigating the metabolism of [14C] deoxyguanosine (dGuo) at physiologic concentrations (10 microM) by unstimulated thymocytes, tonsil-derived T and B lymphocytes, and peripheral blood cells over short time periods. GTP was the principal metabolite formed from dGuo by all cell types with functional PNP and hypoxanthine-guanine phosphoribosyltransferase, confirming formation via degradation to guanine with subsequent salvage by hypoxanthine-guanine phosphoribosyltransferase. Thymocytes also formed a small amount of deoxyguanosine triphosphate (dGTP), presumably through direct phosphorylation by deoxycytidine kinase. Incorporation of dGuo into GTP was effectively inhibited in all instances under PNP deficiency conditions and dGTP levels increased up to 10-fold in thymocytes, but tonsil-derived B or T lymphocytes and unfractionated PBL still accumulated no detectable dGTP. E and platelets formed low amounts of dGTP under these conditions. Preincubation with adenine (50 microM) to reverse any Guo-induced toxicity reduced the incorporation of dGuo into GTP without inhibitor in all cell types with intact adenine phosphoribosyltransferase, but had no effect on dGTP accumulation in thymocytes, with or without inhibitor, thus excluding any indirect formation of dGTP via the de novo route. The rapid metabolism of dGuo to GTP, in the absence of PNP inhibition and subsequent effects of the altered GTP concentrations on cellular metabolism, may account for the differing responses reported by investigators with the use of low dGuo concentrations (enhancing), compared with high (inhibitory), concentrations in mitogen-stimulated lymphocyte studies. The exclusive ability of thymocytes to accumulate significant amounts of dGTP, and inability of B cells to do so, provides a logical explanation for the selective T cell immunodeficiency in PNP deficiency.

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The behavior of plasma and urine oxypurines (hypoxanthine and xanthine) and of uric acid has been studied in normal subjects and in gout patients. Oxypurines and uric acid were increased in the plasma of gout patients but only the urinary excretion of hypoxanthine was higher in this group. The interpretation of the observed variations is discussed.

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The clearance of uric acid, hypoxanthine and xanthine has been examined in gout patients and in normal subjects compared to creatinine, after a purine-free diet. The treatment decreased the clearance in normal subjects, but showed an opposite effect in gout patients. The clearances both of uric acid, hypoxanthine and xanthine were enhanced by allopurinol. The interpretation of the observed variations is discussed.

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The clearance of uric acid, hypoxanthine and xanthine has been examined in gouty patients and in normal subjects comparatively to the creatinine clearance. The clearance of the three purine compounds was lower in the gouty patients, while the creatinine clearance showed a normal behavior. These results indicate that either the tubular excretion or the carriers of the considered metabolites probably undergo specific alterations in the gout.

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Plasma and urine oxypurines (hypoxanthine and xanthine) and uric acid, were evaluated in normal subjects and in gouty patients before and after a purine free diet. After a 7-days period, plasma oxypurines were remarkably higher in normal subjects, while they did not undergo variations in gouty patients, which showed higher in basal conditions. No significant changes in urinary excretion were observed in both cases. The interpretation of the observed variations is discussed.

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The authors investigated the possible correlation between blood concentrations and clinical outcome in 38 auranofin-treated patients with rheumatoid arthritis, diagnosed according to ARA criteria. The results showed that the whole blood gold concentrations did not correlate with the clinical parameters investigated and some laboratory findings. The authors discuss this lack of correlation, suggesting that a clear genetic disposition can interfere with the clinical response, affecting the metabolism and kinetics of the drug.

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The urinary excretion of proteins, N-acetyl-3-glucosaminidase and leucine aminopeptidase, was measured in 50 patients with rheumatoid arthritis (RA), of whom 20 subjects were on nonsteroidal anti-inflammatory drugs (NSAIDs) and 30 on gold salts. No pathological changes of the above-mentioned urinary parameters have been observed in the group of RA patients, in comparison with control subjects and patients suffering from osteoarthritis treated with NSAIDs.

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Chlorinated ethenes are toxic substances which are widely distributed groundwater contaminants and are persistent in the subsurface environment. Reports on the biodegradation of these compounds under anaerobic conditions which might occur naturally in groundwater show that these substances degrade very slowly, if at all. Previous attempts to degrade chlorinated ethenes aerobically have produced conflicting results. A mixed culture containing methane-utilizing bacteria was obtained by methane enrichment of a sediment sample. Biodegradation experiments carried out in sealed culture bottles with radioactively labeled trichloroethylene (TCE) showed that approximately half of the radioactive carbon had been converted to 14CO2 and bacterial biomass. In addition to TCE, vinyl chloride and vinylidene chloride could be degraded to products which are not volatile chlorinated substances and are therefore likely to be further degraded to CO2. Two other chlorinated ethenes, cis and trans-1,2-dichloroethylene, were shown to degrade to chlorinated products, which appeared to degrade further. A sixth chlorinated ethene, tetrachloroethylene, was not degraded by the methane-utilizing culture under these conditions. The biodegradation of TCE was inhibited by acetylene, a specific inhibitor of methane oxidation by methanotrophs. This observation supported the hypothesis that a methanotroph is responsible for the observed biodegradations.

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Renal ischemia causes a reversible loss of microvillar membrane (MVM) of the proximal tubule cell and of MVM enzyme specific activities (S.A.). We sought to determine if recovery of the MVM glycoprotein was accomplished through de novo synthesis or recycling. Renal ischemia (25 min) was induced in rats by occlusion of the left renal artery, followed by 15 min or 4 hrs of reflow of blood. Radiolabelled fucose was injected into rats before or after ischemia and was used as a marker for new glycoprotein synthesis or recycling of prelabelled glycoprotein. Ischemia, followed by 15 min of reflow, caused a 49% reduction in protein associated with the isolated MVM fraction of the ischemic kidney. There was also a decrease in newly fucosylated glycoprotein in both homogenate and MVM fraction measured as S.A. or total amount of labeled glycoprotein. Pre-labelled glycoproteins had no change in S.A. in homogenates or MVM fractions of ischemic or contralateral kidneys. However, the total amount of labeled glycoprotein in the ischemic MVM fraction was reduced. At 4 hrs of reflow, protein content of the MVM fraction was back to normal. Pre-labelled glycoproteins of the ischemic homogenate and MVM fraction were also back to normal with no significant dilution of glycoprotein S.A. by newly synthesized protein, indicating that glycoprotein recycling occurs to a large extent in the ischemic kidney.

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