Impact of polymorphism rs7041 and rs4588 of Vitamin D Binding Protein on the extent of coronary artery disease.

BACKGROUND AND AIM: 25-hydroxyvitamin D deficiency represents a widespread social problem but also an emerging risk factor for cardiovascular disease. Genetic variants of the Vitamin D Binding Protein (VDBP), the main transporter of vitamin D in the bloodstream, have been shown to account for a significant variability in the levels and systemic effects of vitamin D. We investigated whether the single nucleotide polymorphisms, rs7041 and rs4588, of VDBP are associated to the prevalence and extent of coronary artery disease. METHODS AND RESULTS: A consecutive cohort of patients undergoing coronary angiography in a single centre were included. Significant CAD was defined as at least 1 stenosis >50%, severe CAD for as left main and/or three-vessel disease. VDBP genetic status was assessed by polymerase chain reaction and restriction fragment length polymorphism technique. We included 1080 patients, 57% carried the mutated G allele of rs7041, whereas 22% carried the A allele of rs4588. Higher levels of C- reactive protein were observed in the carriers of G allele of rs7041 (p = 0.02), whereas 25-hydroxyvitamin D levels were similar across groups. A higher prevalence of lesions in the left anterior descending artery and a longer lesion length were observed in "A" carriers for rs4588 (p = 0.04 and p = 0.03, respectively). On the contrary, a higher prevalence of bifurcation lesions and chronic occlusions was observed in G carriers (p = 0.002 and p = 0.01 respectively). Both polymorphisms of VDBP did not affect the prevalence of CAD (rs7041: 79.1% TT vs 80.3% TG vs 78.5% GG, p = 0.81; rs4588 = 80.3% CC vs 78.5% AC + AA, p = 0.49) and severe CAD, (rs7041: 31.1% TT % vs 31.3% TG vs 30.6% GG, p = 0.88; rs4588: 32.2% CC vs 29.3% AC + AA, p = 0.31). Results were confirmed at multivariate analysis, for both rs7041 and rs4588. However, when including the levels of 25-hydroxyvitamin D in the multivariate model, we observed that 25(OH)D status and not genetic variants of VDBP were significantly associated with CAD (25-hydroxyvitamin D OR [95% CI] = 0.99 [0.97-1.0], p = 0.05; rs7041 TG: OR [95% CI] = 1.26 [0.73-2.19], p = 0.41; rs7041 GG: OR [95% CI] = 1.25 [0.82-1.91], p = 0.30; rs4588 AC + AA: OR [95% CI] = 0.76 [0.51-1.13], p = 0.18). CONCLUSION: This study showed in a large cohort of patients undergoing coronary angiography, that the polymorphisms rs7041 and rs4588 of VDBP are not associated with the levels of 25-hydroxyvitamin D nor with the prevalence and extent of CAD. In fact, 25-hydroxyvitamin D levels but not VDBP genetic status independently predicted the occurrence of coronary lesions at angiography.

Uric acid and high-residual platelet reactivity in patients treated with clopidogrel or ticagrelor.

BACKGROUND AND AIM: High residual platelet reactivity (HRPR) is still an important challenge, despite the advent of new potent ADP-antagonists. Therefore it is of extreme importance to identify factors that can influence platelet activation. Serum uric acid (SUA) has been largely addressed in the past as a possible risk factor for coronary artery disease, with a possible association with platelets hyperreactivity. So far no studies have assessed the role of serum uric acid on the response to dual antiplatelet therapy. Therefore, the aim of our study was to evaluate the impact of uric acid levels on platelet function in patients treated with dual antiplatelet therapy (DAPT) with clopidogrel or ticagrelor. METHODS AND RESULTS: We scheduled for platelet function assessment at 30-90 days post-discharge patients treated with DAPT (ASA + clopidogrel or ticagrelor) for an ACS or elective percutaneous coronary intervention (PCI). Platelet function was assessed by whole blood impedance aggregometry (Multiplate(®)-Roche Diagnostics AG), HRPR was considered for ASPI test >862 AU(∗)min (for ASA) and ADP test values ≥417 AU* min (for ADP-antagonists). RESULTS: We included a total of 493 patients (262 were on ASA and clopidogrel and 231 on ASA and ticagrelor). Patients were divided according to quartiles of serum uric acid levels measured at the time of platelet aggregation assessment (Group 1 <4.6 mg/dL, n = 114; Group 2, 4.7-5.8 mg/dL, n = 133; Group 3, 5.9-6.8 mg/dL, n = 124; Group 4, >6.9, n = 122). Patients with higher uric acid levels were older, more often smokers, with history of hypertension and previous coronary artery bypass surgery and renal failure and were more often on therapy with diuretics at admission. Patients with higher SUA had higher triglycerides and fibrinogen. Uric acid levels did not influence ASPI, COL, TRAP and ADP tests. High residual platelet reactivity (HRPR) was observed in 1.5% of patients treated with ASA, with no difference according to SUA quartiles (p = 0.60), confirmed at multivariate analysis after correction for baseline confounders (adjusted OR[95%CI] = 1.05 [0.44-2.52], p = 0.90). HRPR for ADP-antagonists was observed in 23.6% of patients, with no difference according to SUA quartiles (p = 0.47); this result was confirmed also after correction for baseline confounders (adjusted OR[95%CI] = 1.04 [0.84-1.28], p = 0.73). Moreover, no association was found between HRPR and uric acid levels both among patients treated with clopidogrel (p = 0.35) or ticagrelor (p = 0.74), that was confirmed after correction for baseline confounding factors (adjusted OR[95%CI] = 1.18 [0.90-1.55], p = 0.23) and (adjusted OR[95%CI] = 0.96 [0.63-1.47], p = 0.85). The absence of association between SUA and platelet reactivity was confirmed at linear regression analysis both with clopidogrel (r = 0.03, p = 0.55) or ticagrelor (r = -0.01, p = 0.85). CONCLUSION: This is the first large study showing that in patients receiving DAPT, uric acid levels do not influence response to ticagrelor and clopidogrel or the effectiveness of ASA.

Serum uric acid levels during dual antiplatelet therapy with ticagrelor or clopidogrel: Results from a single-centre study.

BACKGROUND AND AIMS: New antithrombotic therapies have significantly improved the outcomes of patients with acute coronary syndrome (ACS), where the introduction of ticagrelor has provided the greatest mortality benefits. However, ticagrelor treatment has been associated with a potential increase in the serum uric acid (SUA) levels, which may influence endothelial dysfunction and prothrombotic status, thereby affecting the risk of acute cardiovascular events in patients requiring dual antiplatelet therapy (DAPT). The present study aimed to compare the impact of antiplatelet agents such as ticagrelor or clopidogrel on SUA levels and their effect on platelet reactivity. METHODS AND RESULTS: We included patients admitted for ACS or elective percutaneous coronary intervention (PCI) and discharged with ASA (acetylsalicylic acid; 100-160 mg) and clopidogrel (75 mg) or ticagrelor (90 mg twice a day). Chemistry was assessed at admission (baseline) and after a 30-90-day period of DAPT (together with platelet reactivity). The absolute and percentage variations of SUA after DAPT introduction were considered. Multiple-electrode aggregometry was used to assess platelet function. A total of 378 patients were enrolled, with 145 treated with aspirin and clopidogrel (AC) and 233 with aspirin and ticagrelor (AT). The AC patients were older (p = 0.003) and more often showed elective PCI as an indication to DAPT (<0.001); they received chronic therapy with ARB (angiotensin II receptor blocker; p = 0.001), nitrates (p = 0.044), CCB (calcium channel blocker; p = 0.005) and diuretics (p = 0.044). The AT patients displayed a higher percentage of ACS diagnosis (p < 0.001) and received chronic therapy with ACE (angiotensin-converting enzyme) inhibitors (p = 0.001), beta blockers (p = 0.001) and statins (p = 0.013). The AC patients displayed higher platelet reactivity at COL (collagen) test, ASPI test and ADP (adenosine diphosphate) test (p = 0.03, 0.001 and <0.001, respectively) and a higher percentage of HRPR (high residual platelet reactivity) in the ADP test (p = 0.001). No difference was found in the baseline uric acid and creatinine levels between AC and AT patients. At 30-90 days, a significant absolute and percentage increase in the SUA levels was found in AT as compared to AC patients (0.204 mg/dl vs. -0.165 mg/dl, p = 0.034; 6.26% vs. -0.005%, p = 0.018, respectively). Results were not influenced by variations in renal function. At multivariate analysis, in fact, ticagrelor therapy emerged as an independent predictor of increase in the uric acid levels (odds ratio (OR; 95% confidence interval (CI)) = 2.79 (1.66-4.67), p < 0.001). However, the variation in the SUA levels did not affect platelet reactivity or HRPR in both AC and AT patients. CONCLUSION: An increase in the SUA levels at 30-90 days was observed in patients receiving chronic DAPT with ticagrelor, but not clopidogrel treatment. However, the changes in the SUA levels do not influence platelet aggregation.

Prognostic significance of AMPK activation in advanced stage colorectal cancer treated with chemotherapy plus bevacizumab.

BACKGROUND: AMP-activated protein kinase (AMPK) has a central role in cellular energy sensing and is activated in preclinical tumour models following anti-vascular endothelial growth factor (VEGF) therapy. The possible predictive or prognostic role of AMPK status in cancer patients treated with anti-VEGF drugs has not been investigated so far. METHODS: Expression of components of the AMPK pathway including phosphorylated AMPK (pAMPK), phosphorylated acetyl-Coa carboxylase (pACC) and liver kinase B1 (LKB1) was investigated by immunohistochemistry in 48 colorectal cancers treated with FOLFIRI plus bevacizumab. Correlation between pAMPK and pACC and associations between the AMPK pathway scores and clinico-pathological characteristics were assessed. Overall survival (OS) was estimated through Kaplan-Meier method, whereas hazard ratios were computed to identify prognostic factors. RESULTS: Fourteen patients (29.2%) were included in the pAMPK-negative group (score ≤5), whereas 34 patients (70.8%) were included in the pAMPK-positive group (score >5). The Spearman's coefficient for the correlation between pAMPK and pACC scores in primary tumour samples was 0.514 (P=0.0002). Low pAMPK levels were associated with worse OS (P-value 0.0002) but not with PFS, whereas low pACC levels were associated both with worse OS and PFS (P-value 0.0007 and 0.01, respectively). CONCLUSIONS: Our findings suggest that high tissue AMPK activation is a prognostic biomarker in this cohort of metastatic colorectal cancer patients.

Causes of hypercalcemia in renal transplant recipients: persistent hyperparathyroidism and others.

Hypercalcemia is common in patients after kidney transplantation (KTx) and is associated with persistent hyperparathyroidism in the majority of cases. This retrospective, single-center study evaluated the prevalence of hypercalcemia after KTx. KTx recipients were evaluated for 7 years after receiving kidneys from living or deceased donors. A total of 301 patients were evaluated; 67 patients had hypercalcemia at some point during the follow-up period. The median follow-up time for all 67 patients was 62 months (44; 80). Overall, 45 cases of hypercalcemia were classified as related to persistent post-transplant hyperparathyroidism (group A), 16 were classified as "transient post-transplant hypercalcemia" (group B), and 3 had causes secondary to other diseases (1 related to tuberculosis, 1 related to histoplasmosis, and 1 related to lymphoma). The other 3 patients had hypercalcemia of unknown etiology, which is still under investigation. In group A, the onset of hypercalcemia after KTx was not significantly different from that of the other groups, but the median duration of hypercalcemia in group A was 25 months (12.5; 53), longer than in group B, where the median duration of hypercalcemia was only 12 months (10; 15) (P<0.002). The median parathyroid hormone blood levels around 12 months after KTx were 210 pg/mL (141; 352) in group A and 72.5 pg/mL (54; 95) in group B (P<0.0001). Hypercalcemia post-KTx is not infrequent and its prevalence in this center was 22.2%. Persistent hyperparathyroidism was the most frequent cause, but other important etiologies must not be forgotten, especially granulomatous diseases and malignancies.

Prospective, randomized comparison of ProSeal and Classic laryngeal mask airways in anaesthetized neonates and infants.

BACKGROUND: When compared with the Classic laryngeal mask airway (cLMA), the recently introduced ProSeal laryngeal mask airway (PLMA) has modified features to produce higher airway seal pressures and enable ventilation in circumstances where the cLMA might fail. The first neonatal size 1 PLMA recently became available. This study was designed to compare the effectiveness of the size 1 cLMA and PLMA during positive pressure ventilation in anesthetized neonates and infants. METHODS: Forty-six consecutive patients undergoing elective cardiac surgical procedures were randomized for initial airway management with the cLMA or PLMA. Insertion time (IT), number of placement attempts, ease of placement, quality of the initial airway, maximum tidal volume (TVmax), and airway pressure at which an audible leak in the mouth (P(leak)) occurred were collected. All data were recorded before performing tracheal intubations. RESULTS: IT and success rate were similar for both LMAs. The initial quality of the airway was significantly better for the PLMA (P<0.05). TVmax and P(leak) were significantly higher for PLMA (77 vs 58 ml, P<0.02 and 29.8 vs 24.4 cm H2O, P<0.02). No adverse events were recorded during the study. CONCLUSIONS: The size 1 PLMA forms a more effective seal than size 1 cLMA in neonates. This might allow the PLMA to be used in those newborn infants requiring high airway pressures for ventilation.

Colonic total and segmental transit times in healthy Italian adults.

PURPOSE: This study was done to determine colonic transit times in healthy Italian adults. MATERIALS AND METHODS: Institutional review board approval and informed patient consent were obtained. Colonic segmental radiopaque markers were counted and transit times calculated in 36 healthy subjects studied using a technique involving daily radiopaque marker ingestion and single radiological visit, with oral administration of 8-10 ml of a thick barium paste as a colonic trace for the marker count. Two independent radiologists counted the marker twice. Observer agreement was assessed using comparison analysis. RESULTS: There was very good observer agreement for the segmental marker counts. The upper limit for colonic transit times was: 45.6 h in the colon as a whole, 31.2 h in the right colon, 19.2 h in the left colon and 16.8 h in the rectosigmoid. Colonic transit times were not gender-related. CONCLUSIONS: In healthy subjects, a barium trace affords optimal visibility of the different colonic segments, enabling accurate location of all markers and thus providing an anatomy-related, repeatable and reproducible fluoroscopic segmental marker count. We suggest that the reference values for normal colonic transit times could be adopted for Italian people irrespective of gender.

[Etiological agents of dermatomycoses isolated in a hospital of Santa Fe City, Argentina]. / Agentes etiológicos de micosis superficiales aislados en un hospital de Santa Fe, Argentina.

Superficial mycoses are limited to skin, hair, nails and mucous membranes. The most common etiological agents are dermatophytes and yeasts of Candida genus. The aim of this work was to know the etiological agents of dermatomycoses and their clinical presentation. Were analized 2073 samples of skin, hair, nails, and oral mucous membranes obtained from 1817 patients who attended the Microbiology Branch of the Central Laboratory at Dr. J. M. Cullen Hospital, since September 1999 to September 2003. The samples were examined and identified according to the localization and type of lesion. Out of the total samples 55.67% were positive; 63% were recovered from females, and 37% from males. The most common localization was the skin. Trichophyton rubrum was the most frequent dermatophyte, and among yeasts, Candida albicans was the prevalent species. Fourteen non-dermatophytic fungi (Fusarium spp. and Aspergillus spp.) were isolated, and considered emergent pathogens from superficial mycoses.

[Evaluation of cefoxitin and cefotaxime screening plates for the detection of methicillin-resistance in Staphylococcus aureus]. / Evaluación de placas de screening de cefoxitina y cefotaxima para la detección de resistencia a meticilina en Staphylococcus aureus.

Detection of methicillin-resistant Staphylococcus aureus (MRSA) isolates represents a serious problem to low and media level microbiology labs. In this work cefoxitin (FOX) and cefotaxime (CTX) screen plates (AS) (8-16 microg/ml) with and without 4% of NaCl were evaluated to detect MRSA. Sensitivity, specificity, positive and negative predictive values were determined. The AS oxacillin and the agglutination test MRSA-Screen Latex for the detection of PLP2a were used as reference methods for the evaluation of the different studied screening plates. The 100% (94 strains) PLP2a positive were detected as MRSA with FOX (8 microg/ml), and CTX (8 microg/ml with 4% NaCl) AS. The advantage of FOX AS (8 microg/ml) is that it does not need the addition of NaCl, and CTX AS (8 microg/ml with 4% NaCl) is that cefotaxime is an antimicrobial easily accessible in our country.

Advanced age and high-residual platelet reactivity in patients receiving dual antiplatelet therapy with clopidogrel or ticagrelor.

UNLABELLED: ESSENTIALS: Dual antiplatelet therapy (DAPT) in elderly patients requires balancing bleedings and thrombosis. Impact of age on high residual on-treatment platelet reactivity (HRPR) on DAPT was studied. A reduced effectiveness of adenosine diphosphate antagonists was observed over 70 years of age. The occurrence of HRPR was increased among elderly patients with both clopidogrel and ticagrelor. BACKGROUND: The aim of the present study was to evaluate the impact of age on platelet function and the occurrence of high residual on-treatment platelet reactivity (HRPR) in patients treated with dual antiplatelet therapy (DAPT) using acetylsalicilic acid (ASA) and clopidogrel or ticagrelor. METHODS: Patients treated with DAPT (ASA and clopidogrel or ticagrelor) were scheduled for platelet function assessment at 30-90 days post-discharge. By whole blood impedance aggregometry, HRPR was considered for ASPI test values > 862 AU*min (for ASA) and adenosine diphosphate (ADP) test values > 417 AU*min (for ADP antagonists). Elderly patients were defined as those aged ≥ 70 years. RESULTS: Among 494 patients on DAPT, 224 (45.3%) were ≥ 70 years old. ADP-mediated platelet aggregation increased with decades of age (279.3 ± 148.6 vs. 319.6 ± 171.1 vs. 347.3 ± 190.1 vs. 345.7 ± 169.2), whereas no difference was observed for ASA response. A reduced effectiveness of ADP antagonists was observed among elderly patients; in fact, among the 117 patients displaying HRPR (23.7%), a higher prevalence was observed among patients over 70 years old (30.4% vs. 18.1%; adjusted odds ratio (OR) [95% confidence interval (CI)] = 2.19 [1.29-3.71]). Similar results were obtained among the 266 clopidogrel-treated patients (38.5% vs. 27.9%; adjusted OR [95% CI] = 2.91 [1.46-5.8]) and in the 228 patients receiving ticagrelor (19.1% vs. 8.1%; adjusted OR [95% CI] = 2.55 [1.02-8.59]). CONCLUSION: In patients receiving dual antiplatelet therapy, advanced age is independently associated with a reduced effectiveness of ADP antagonists and a higher rate of HRPR with both clopidogrel and ticagrelor.

Causes of hypercalcemia in renal transplant recipients: persistent hyperparathyroidism and others

Hypercalcemia is common in patients after kidney transplantation (KTx) and is associated with persistent hyperparathyroidism in the majority of cases. This retrospective, single-center study evaluated the prevalence of hypercalcemia after KTx. KTx recipients were evaluated for 7 years after receiving kidneys from living or deceased donors. A total of 301 patients were evaluated; 67 patients had hypercalcemia at some point during the follow-up period. The median follow-up time for all 67 patients was 62 months (44; 80). Overall, 45 cases of hypercalcemia were classified as related to persistent post-transplant hyperparathyroidism (group A), 16 were classified as "transient post-transplant hypercalcemia" (group B), and 3 had causes secondary to other diseases (1 related to tuberculosis, 1 related to histoplasmosis, and 1 related to lymphoma). The other 3 patients had hypercalcemia of unknown etiology, which is still under investigation. In group A, the onset of hypercalcemia after KTx was not significantly different from that of the other groups, but the median duration of hypercalcemia in group A was 25 months (12.5; 53), longer than in group B, where the median duration of hypercalcemia was only 12 months (10; 15) (P<0.002). The median parathyroid hormone blood levels around 12 months after KTx were 210 pg/mL (141; 352) in group A and 72.5 pg/mL (54; 95) in group B (P<0.0001). Hypercalcemia post-KTx is not infrequent and its prevalence in this center was 22.2%. Persistent hyperparathyroidism was the most frequent cause, but other important etiologies must not be forgotten, especially granulomatous diseases and malignancies.

Effect of several sterilisation techniques on homogeneous self assembled monolayers.

Understanding how cells sense their environment and are able to regulate their metabolism is of great importance for the success of biomaterials implantation. Self assembled monolayers (SAMs) are in use nowadays to model the surface of such materials. They permit the control of different surface parameters (like chemistry, surface energy and topography) enabling to get a greater insight in cells behaviour when interacting with surfaces and thus, in the future, to enhance surface properties of biomaterials. As sterilisation is the compulsory step for in vitro and in vivo assays with living biological materials, it is important to know how SAMs react under sterilisation techniques in use on biomaterials. In this work, the effect of three types of sterilisation techniques: gamma-irradiation, mostly used on biomaterials, dry heat and steam autoclaving, have been investigated on NH2 and CH3 terminated SAMs. Gamma-irradiation destructs drastically the NH2 and partially the CH3 monolayers by producing oxidative compounds (COOH, C=O, C-OH). The main product induced by gamma-irradiation on NH2 monolayers is carboxylic acid, whereas CH3 shows an important increase in the amount of alcoholic groups. This difference in deterioration is assumed to be due to the higher stability of the CH3 monolayer. Steam autoclaving to a lesser extent gives the same results on NH2 monolayers. Dry heat seems to be the most reliable technique, which can be used on such surfaces as it removes physically adsorbed organic contaminants without affecting the integrity of the surface.

A self-oscillating detuning-insensitive class-E transmitter for implantable microsystems.

This paper describes a low-cost, self-oscillating, detuning-in-sensitive, class-E driver for transcutaneous power and data transmission to implantable microsystems. A voltage feedback scheme using a fast comparator for zero-crossing detection and a CMOS start-up circuit were used to stabilize the class-E operation for various transmitter coil inductance values. This technique solves the common problem of mismatch between the switching frequency of the driving device and the resonant frequency of the load network, which can cause excessive power loss and damage to the active device. Data is transmitted by AM modulation of the carrier through switching the power supply between two levels. The transmitter uses a 9-V supply, consumes 212 mA, operates at 3.9 MHz, and has an efficiency of 71%. The efficiency is stable (< 2% change) against 13% variations in the inductance value of a pancake shaped transmitter coil. Index Terms-Biomedical microsystems, class-E transmitter, implantable electronics, inductive powering, transcutaneous links.

A single-channel implantable microstimulator for functional neuromuscular stimulation.

This paper describes a single-channel implantable microstimulator for functional neuromuscular stimulation. This device measures 2 x 2 x 10 mm3 and can be inserted into paralyzed muscle groups by expulsion from a hypodermic needle. Power and data to the device are supplied from outside by RF telemetry using an amplitude-modulated 2-MHz RF carrier generated using a high-efficiency class-E transmitter. The transmitted signal carries a 5-b address which selects one of the 32 possible microstimulators. The selected device then delivers up to 2 microC of charge store in a tantalum chip capacitor for up to 200 microseconds (10 mA) into loads of < 800 omega through a high-current thin-film iridium-oxide (IrOx) electrode (approximately 0.3 mm2 in area). A bi-CMOS receiver circuitry is used to: generate two regulated voltage supplies (4.5 and 9 V), recover a 2-MHz clock from the carrier, demodulate the address code, and activate the output current delivery circuitry upon the reception of an external command. The overall power dissipation of the receiver circuitry is 45-55 mW. The implant is hermetically packaged using a custom-made glass capsule.

[Phaeohyphomicosis by Wangiella dermatitidis in Republic Argentine.]. / Feohifomicosis producida por Wangiella dermatitidis en la República Argentina.

We are presenting the case of a 54 year-old woman, who had a kidney transplant. She came to our laboratory to consult for two cutaneous lesions: a cystic one at the back of her right leg and one localized on dorsum of left forearm. Biopsies of both lesions were performed for a histopathologic study as well as microbiological (both bacteriologic and mycologic) cultures. The histopathologic study showed a lesion compatible with a B type cutaneous lymphoma in the lesion in her leg, while in the mycologic study of the cystic lesion elements compatible with phaeohyphomycosis were observed. Development of Wangiella dermatitidis was obtained in the cultures. The cystic lesion localized on forearm was completely removed by surgery, while the lesion in the leg received oncological treatment. The aim of this paper is to describe the first published case of phaeohyphomycosis, by W. dermatitidis, in the Argentine Republic.

[Comparison of visual results and quality of vision between two multifocal intraocular lenses. Multifocal silicone and bifocal PMMA]. / Résultats comparatifs visuels et qualité de vision de deux implants multifocaux. Silicone multifocal et PMMA bifocal]

PURPOSE: To compare visual results and quality of vision of two multifocal intraocular lenses (IOL): SA 40 N silicone zonal-progressive multifocal IOL and P 359 TUV PMMA bifocal IOL. METHODS: 46 eyes were operated on for cataract. 24 IOL SA 40 N (group 1) and 22 IOL P 359 (group 2) were implanted. Evaluation of visual results was performed between the first and the third month postoperatively. The quality of vision was explored in both groups by using two tests of contrast sensitivity, an automated visual field and a questionnaire dealing with patient satisfaction and presence of halos and glare. RESULTS: Postoperatively, a myopic shift was noted with a statistical significant difference in the group 2 (p<0.05). The predictability was good in both groups (mean refractive error<1 D). Mean corrected distance visual acuity was similar in-groups 1 and 2 (0.6). Mean distance-corrected near visual acuity was statistically better in the group 2 (p<0.05). We noted in both groups a loss of contrast sensitivity statistically more important in the group 2 (p<0.001). Where the automated perimetry is concerned, no statistical differences were encountered. 35% of patients (group 1) and 29% (group 2) were very satisfied with the results of their surgery. Halos and glare were noted in 8% (group 1) and 9% (group 2) of the patients. CONCLUSION: The new concept of multifocality is increasing in practice of cataract surgery because of the reduction of spectacle dependency and the high level of patient satisfaction. However, the occurrence of halos and glare suggest a limitation of these indications of multifocal IOL, particularly for night driving patients.

Effect of ultrasounds on the electrochemical synthesis of polypyrrole, application to the adhesion and growth of biological cells.

In this study, a new way to synthesize polypyrrole films is presented. This original way consists in the electropolymerization of polypyrrole under high frequency ultrasonic irradiation on conductive fluorine-doped tin oxide surfaces. The polypyrrole films obtained are then compared, in terms of chemical structure and morphology, to polypyrrole films synthesized by standard electrochemical methodology. Next, these polymer films are tested as an alternative to biomaterials that are commonly used as cell culture substrates. Thus, the adhesion and growth of osteoblastics cells and microbial cells on polymer-modified surfaces are investigated by using qualitative observation and quantitative tests. These studies proved the non-toxicity of the polymer films for osteoblastic and microbial cells but also a different behaviour of osteoblastic cells and microbial cells with polypyrrole films.

Mechanically responsive films of variable hydrophobicity made of polyelectrolyte multilayers.

Mechanically responsive surfaces that allow to switch reversibly from a hydrophobic to a hydrophilic substrate are reported. The surfaces are constituted of polyelectrolyte multilayers deposited on modified charged silicone sheets. n bilayers of poly(allylamine)-Nafion (PAH-Naf) and m bilayers of poly(allylamine)-poly(acrylic acid) (PAH-PAA) composed the multilayers. A (PAH-Naf)(n) film possesses a water contact angle of around 105 degrees, whereas the contact angle of a (PAH-Naf)(4)-(PAH-PAA)(m) multilayer is around 50 degrees. When such a film with m < 5 and terminated by PAA is stretched out, its water contact angle increases up to around 100 degrees. Successive elongation/retraction cycles allow the water contact angle to alternate reversibly between 100 and 57 degrees indicating the reversible mechanical responsive nature of the film.