Adaptative mechanism of the equilibrative nucleoside transporter 1 (ENT-1) and blood adenosine levels in elite freedivers.

PURPOSE: Long static or intense dynamic apnoea-like high-altitude exposure is inducing hypoxia. Adenosine is known to participate to the adaptive response to hypoxia leading to the control of heart rate, blood pressure and vasodilation. Extracellular adenosine level is controlled through the equilibrative nucleoside transporter 1 (ENT-1) and the enzyme adenosine deaminase (ADA). The aim of this study was to determine the control of adenosine blood level (ABL) via ENT-1 and ADA during apnoea-induced hypoxia in elite freedivers was similar to high-altitude adaptation. METHODS: Ten freediver champions and ten controls were studied. Biological (e.g. ENT-1, ADA, ABL, PaO2, PaCO2 and pH) and cardiovascular (e.g. heart rate, arterial pressure) parameters were measured at rest and after a submaximal dry static apnoea. RESULTS: In freedivers, ABL was higher than in control participants in basal condition and increased more in response to apnoea. Also, freedivers showed an ADA increased in response to apnoea. Finally, ENT-1 level and function were reduced for the free divers. CONCLUSION: Our results suggest in freedivers the presence of an adaptive mechanism similar to the one observed in human exposed to chronic hypoxia induced by high-altitude environment.

Adenosine plasma level correlates with homocysteine and uric acid concentrations in patients with coronary artery disease.

The role of hyperhomocysteinemia in coronary artery disease (CAD) patients remains unclear. The present study evaluated the relationship between homocysteine (HCys), adenosine plasma concentration (APC), plasma uric acid, and CAD severity evaluated using the SYNTAX score. We also evaluated in vitro the influence of adenosine on HCys production by hepatoma cultured cells (HuH7). Seventy-eight patients (mean age ± SD: 66.3 ± 11.3; mean SYNTAX score: 19.9 ± 12.3) and 30 healthy subjects (mean age: 61 ± 13) were included. We incubated HuH7 cells with increasing concentrations of adenosine and addressed the effect on HCys level in cell culture supernatant. Patients vs. controls had higher APC (0.82 ± 0.5 µmol/L vs 0.53 ± 0.14 µmol/L; p < 0.01), HCys (15 ± 7.6 µmol/L vs 6.8 ± 3 µmol/L, p < 0.0001), and uric acid (242.6 ± 97 vs 202 ± 59, p < 0.05) levels. APC was correlated with HCys and uric acid concentrations in patients (Pearson's R = 0.65 and 0.52; p < 0.0001, respectively). The SYNTAX score was correlated with HCys concentration. Adenosine induced a time- and dose-dependent increase in HCys in cell culture. Our data suggest that high APC is associated with HCys and uric acid concentrations in CAD patients. Whether the increased APC participates in atherosclerosis or, conversely, is part of a protective regulation process needs further investigations.

[Differential diagnosis between keloid and hypertrophic scars: a new approach by full-field optical coherence tomography]. / Diagnostic différentiel entre cicatrices chéloïdes et hypertrophiques : une nouvelle approche en tomographie par cohérence optique plein-champ.

OBJECTIVE: To evaluate the efficacy of full-field optical coherence tomography to differentiate hypertrophic and keloid scars on ex-vivo tissues. PATIENTS AND METHODS: All patients who underwent resection of pathological scar from November 2012 to September 2013 were analyzed. The scars were fixed in formalin and analyzed by conventional histology and full-field optical coherence tomography. The criteria for evaluation were: presence of dermal nodules, presence of cells and hyalinization of collagen. RESULTS: Nineteen pathological scars were analyzed. Histology found 7 keloid scars, 7 mixed and 3 hypertrophic scars. The sensitivity of optical coherence tomography for the detection of dermal nodules was 100%. This technology was not helpful for detection of cells and hyalinized collagen. CONCLUSION: In the present state of technology, optical coherence tomography did not identify the presence of cells, which makes the differential diagnosis difficult in the case of hypertrophic and keloid scars.

An experimental porcine model of heterotopic renal autotransplantation.

OBJECTIVE: The aim of the present study was to validate an experimental model of heterotopic renal allotransplantation. Such a model, more relevant to the human situation, has never been previously described. MATERIALS AND METHODS: Pietrin pigs (40 to 50 kg) were used in the study. Through a midline incision, the left kidney was removed, washed, and preserved in a standard preservation solution (Celsior, Genzyme, France) for 20 hours at 4 °C. Heterotopic autotransplantation was performed into the right iliac fossa onto the external iliac vessels with an end-to-side anastomosis and a nonstented uretero-ureteral anastomosis was performed. RESULTS: Twenty-five renal allotransplantations were performed over a 5-month time period. Mean operating time progressively decreased and stabilized after 15 procedures (mean ± SD: 78.2 ± 19 minutes and 187.4 ± 18 minutes for left nephrectomy and transplantation, respectively) as morbidity decreased concomitantly. Suturing times for end-to-side anastomosis of the renal artery and vein onto the external iliac artery and vein were 21.9 ± 7 minutes and 34 ± 8 minutes (mean ± SD), respectively. Ten pigs died before the end of the experiment. CONCLUSIONS: We have developed and validated the first nonrodent animal model of heterotopic renal autotransplantation relevant to the human anatomy and physiology. The procedure was easy to learn and safe. This model could be used to teach junior surgeons renal transplantation techniques and could also be used as a model to study ischemia-reperfusion injury in renal transplantation.

Low-dose Ara-C in myelodysplastic syndromes and acute nonlymphoid leukemia. Experience with seven patients.

Seven patients were treated with low dose Ara-C (LDAC). Five patients had acute nonlymphoid leukemia (ANLL), two patients had myelodisplastic syndrome (MDS): refractory anemia (RA) and refractory anemia with excess of blasts in transformation (RAEB-t). Ara-C treatment was given by s.c. injections at a dose of 10-11 mg/m2 every 12 h and only on two occasions by continuous infusion. No improvement, or limited improvement, was observed in five patients and they died of leukemia or of disease-related complications. Two patients with ANLL achieved remission: the first patient after bone marrow aplasia, the second without aplasia but with morphologic evidence of granulocytic differentiation of leukemic cells.

[Correlation between preincubation time of the leukocyte feeder-layer and in vitro granulocytic-macrophage colony growth]. / Rapporti tra tempo di preincubazione del feeder-layer leucocitario e crescita in vitro di colonie granulocitiche-macrofagiche.

Granulocytic-macrophage colony in vitro formation depends on the presence of the colony stimulating factor (CSF). When, in double layer agar method, the CSF is provided from leucocyte underlayers, the pre-incubation time of the feeder-layers must be kept constant. The results obtained in this study have demonstrated in fact that the growth of the colonies can be remarkably different if feeder-layers are incubated for 1, 7 or 14 days.