Mitochondrial neurogastrointestinal encephalomyopathy: Clinical and biochemical impact of allogeneic stem cell transplantation in a Greek patient with one novel TYMP mutation

We describe the case of a Greek female patient with the Classic form of the ultra- rare and fatal autosomal recessive disorder Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) and the impact of allogeneic hematopoietic stem cell transplantation on the biochemical and clinical aspects of the disease. The patient presented at the age of 15 years with severe gastrointestinal symptoms, cachexia, peripheral neuropathy and diffuse leukoencephalopathy. The diagnosis of MNGIE disease was established by the increased levels of thymidine and deoxyuridine in plasma and the complete deficiency of thymidine phosphorylase activity. The novel c.[978dup] (p.Ala327Argfs*?) variant and the previously described variant c.[417 + 1G > A] were identified in TYMP. The donor for the allogeneic hematopoietic stem cell transplantation was her fully compatible sister, a carrier of the disease. The patient had a completely uneventful post- transplant period and satisfactory PB chimerism levels. A marked and rapid decrease in thymidine and deoxyuridine plasma levels and an increase of the thymidine phosphorylase activity to the levels measured in her donor sister was observed and is still present sixteen months post-transplant. Disease symptoms stabilized and some improvement was also observed both in her neurological and gastrointestinal symptoms. Follow up studies will be essential for determining the long term impact of allogeneic hematopoietic stem cell transplantation in our patient.

Fluid-structure interaction simulations outperform computational fluid dynamics in the description of thoracic aorta haemodynamics and in the differentiation of progressive dilation in Marfan syndrome patients

Abnormal fluid dynamics at the ascending aorta may be at the origin of aortic aneurysms. This study was aimed at comparing the performance of computational fluid dynamics (CFD) and fluid-structure interaction (FSI) simulations against four-dimensional (4D) flow magnetic resonance imaging (MRI) data; and to assess the capacity of advanced fluid dynamics markers to stratify aneurysm progression risk. Eight Marfan syndrome (MFS) patients, four with stable and four with dilating aneurysms of the proximal aorta, and four healthy controls were studied. FSI and CFD simulations were performed with MRI-derived geometry, inlet velocity field and Young's modulus. Flow displacement, jet angle and maximum velocity evaluated from FSI and CFD simulations were compared to 4D flow MRI data. A dimensionless parameter, the shear stress ratio (SSR), was evaluated from FSI and CFD simulations and assessed as potential correlate of aneurysm progression. FSI simulations successfully matched MRI data regarding descending to ascending aorta flow rates (R 2 = 0.92) and pulse wave velocity (R 2 = 0.99). Compared to CFD, FSI simulations showed significantly lower percentage errors in ascending and descending aorta in flow displacement (-46% ascending, -41% descending), jet angle (-28% ascending, -50% descending) and maximum velocity (-37% ascending, -34% descending) with respect to 4D flow MRI. FSI- but not CFD-derived SSR differentiated between stable and dilating MFS patients. Fluid dynamic simulations of the thoracic aorta require fluid-solid interaction to properly reproduce complex haemodynamics. FSI- but not CFD-derived SSR could help stratifying MFS patients.

Effect of fatty acids on self-assembly of soybean lecithin systems

With the increasing interest in natural formulations for drug administration and functional foods, it is desirable a good knowledge of the phase behavior of lecithin/fatty acid formulations. Phase structure and properties of ternary lecithin/fatty acids/water systems are studied at 37°C, making emphasis in regions with relatively low water and fatty acid content. The effect of fatty acid saturation degree on the phase microstructure is studied by comparing a fully saturated (palmitic acid, C16:0), monounsaturated (oleic acid, C18:1), and diunsaturated (linoleic acid, C18:2) fatty acids. Phase determinations are based on a combination of polarized light microscopy and small-angle X-ray scattering measurements. Interestingly, unsaturated (oleic acid and linoleic acid) fatty acid destabilizes the lamellar bilayer. Slight differences are observed between the phase diagrams produced by the unsaturated ones: small lamellar, medium cubic and large hexagonal regions. A narrow isotropic fluid region also appears on the lecithin-fatty acid axis, up to 8wt% water. In contrast, a marked difference in phase microsctructure was observed between unsaturated and saturated systems in which the cubic and isotropic fluid phases are not formed. These differences are, probably, a consequence of the high Krafft point of the C16 saturated chains that imply rather rigid chains. However, unsaturated fatty acids result in more flexible tails. The frequent presence of, at least, one unsaturated chain in phospholipids makes it very likely a better mixing situation than in the case of more rigid chains. This swelling potential favors the formation of reverse hexagonal, cubic, and micellar phases. Both unsaturated fatty acid systems evolve by aging, with a reduction of the extension of reverse hexagonal phase and migration of the cubic phase to lower fatty acid and water contents. The kinetic stability of the systems seems to be controlled by the unsaturation of fatty acids.

Catanionic vesicles and DNA complexes: a strategy towards novel gene delivery systems

Catanionic vesicles and DNA form complexes, the structure and composition of which depend on the DNA content. The DNA undergoes a reversible compaction process and its release can be triggered by adding an anionic surfactant to the complexes.

Cerebrospinal fluid synaptic proteins as useful biomarkers in tyrosine hydroxylase deficiency

Tyrosine hydroxylase (TH) deficiency is an inborn error of dopamine biosynthesis and a cause of early parkinsonism. Two clinical phenotypes have been described. Type "B": early onset severe encephalopathy; type "A": later onset, less severe and better response to L-dopa. We aimed to study the expression of several key dopaminergic and gabaergic synaptic proteins in the cerebrospinal fluid (CSF) of a series of patients with TH deficiency and their possible relation with the clinical phenotype and response to L-DOPA. Dopamine transporter (DAT), D2-receptor and vesicular monoamine transporter (VMAT2) were measured in the CSF of 10 subjects with TH deficiency by Western blot analysis. In 3 patients, data of pre- and post-treatment with L-DOPA were available, and in one of them, GABA vesicular transporter was determined. Results were compared to an age-matched control population. The concentration of D2-receptors in CSF was significantly higher in patients with TH deficiency than in controls. Similarly, DAT and vesicular monoamine transporter type 2 were up-regulated. Studies performed before L-DOPA, and on L-DOPA therapy showed a paradoxical response with D2 receptor expression increase as L-Dopa doses and homovanillic concentration gradually raised in a B phenotype patient. The opposite results were found in two patients with A phenotype. However, this is a very small sample, and further studies are needed to conclude robust differences between phenotypes. Synaptic proteins are detectable in the CSF and their quantification can be useful for understanding the pathophysiology of neurotransmitter defects and potentially to adjust and personalize treatments in the future.

Niosomes based on synthetic cationic lipids for gene delivery: the influence of polar head-groups on the transfection efficiency in HEK-293, ARPE-19 and MSC-D1 cells

We designed niosomes based on three lipids that differed only in the polar-head group to analyze their influence on the transfection efficiency. These lipids were characterized by small-angle X-ray scattering before being incorporated into the niosomes which were characterized in terms of pKa, size, zeta potential, morphology and physical stability. Nioplexes were obtained upon the addition of a plasmid. Different ratios (w/w) were selected to analyze the influence of this parameter on size, charge and the ability to condense, release and protect the DNA. In vitro transfection experiments were performed in HEK-293, ARPE-19 and MSC-D1 cells. Our results show that the chemical composition of the cationic head-group clearly affects the physicochemical parameters of the niosomes and especially the transfection efficiency. Only niosomes based on cationic lipids with a dimethyl amino head group (lipid 3) showed a transfection capacity when compared with their counterparts amino (lipid 1) and tripeptide head-groups (lipid 2). Regarding cell viability, we clearly observed that nioplexes based on the cationic lipid 3 had a more deleterious effect than their counterparts, especially in ARPE-19 cells at 20/1 and 30/1 ratios. Similar studies could be extended to other series of cationic lipids in order to progress in the research on safe and efficient non-viral vectors for gene delivery purposes.

Rare Late-Onset Presentation of Glutaric Aciduria Type I in a 16-Year-Old Woman with a Novel GCDH Mutation

Glutaric acidemia type I (GA-I) is a treatable autosomal recessive disorder of lysine, hydroxylysine, and tryptophan metabolism caused by glutaryl-CoA dehydrogenase (GCDH) deficiency. Presentation and progression of disease are variable ranging from asymptomatic carrier state to catastrophic encephalopathy. GA-I usually presents before age 18 months, usually triggered by childhood infection, with mild or severe acute encephalopathy, striatal degeneration, and movement disorder, most often acute dystonia. At a presymptomatic stage diagnosis is suggested clinically by macrocephaly, radiologically by widened Sylvian fissures and biochemically by the presence of excess 3-hydroxyglutaric acid and glutaric acid in urine. Treatment consists of lysine-restricted diet and carnitine supplementation, specific diet restrictions, as well as symptomatic and anticatabolic treatment of intercurrent illness. Presymptomatic diagnosis and treatment are essential to prognosis. We report the case of 16-year-old macrocephalic female with late-onset GA-I and unusual paucisymptomatic presentation with fainting after exercise and widespread white matter signal changes at MRI. She was compound heterozygote for a novel mutation (IVS10-2A>G) affecting splicing at GCDH and a common missense mutation (c. 1240C>T; p.Arg402Trp, R402W). Interestingly, the site of the novel mutation is the nucleotide position of a common mutation found almost exclusively in patients of Chinese/Taiwanese origin (IVS10-2A>C).

Structure and phase equilibria of the soybean lecithin/PEG 40 monostearate/water system

PEG stearates are extensively used as emulsifiers in many lipid-based formulations. However, the scheme of the principles of the lipid-surfactant polymer interactions are still poorly understood and need more studies. A new phase diagram of a lecithin/PEG 40 monostearate/water system at 30 °C is reported. First, we have characterized the binary PEG 40 monostearate/water system by the determination of the critical micelle concentration value and the viscous properties. Then, the ternary phase behavior and the influence of phase structure on their macroscopic properties are studied by a combination of different techniques, namely, optical microscopy, small-angle X-ray scattering, differential scanning calorimetry, and rheology. The phase behavior is complex, and some samples evolve even at long times. The single monophasic regions correspond to micellar, swollen lamellar, and lamellar gel phases. The existence of extended areas of phase coexistence (hexagonal, cubic, and lamellar liquid crystalline phases) may be a consequence of the low miscibility of S40P in the lecithin bilayer as well as of the segregation of the phospholipid polydisperse hydrophobic chains. The presence of the PEG 40 monostearate has less effect in the transformation to the cubic phase for lecithin than that found in other systems with simple glycerol-based lipids.

The phenotypic spectrum of paediatric neurotransmitter diseases and infantile parkinsonism

Paediatric neurotransmitter diseases are a group of inherited disorders attributable to a disturbance of neurotransmitter metabolism. The monoamines, catecholamines and serotonin, also called biogenic amines, are neurotransmitters with multiple roles including psychomotor function, hormone secretion, cardiovascular, respiratory and gastrointestinal control, sleep mechanisms, body temperature and pain. Given the multiple functions of monoamines, disorders of their metabolism comprise a wide spectrum of manifestations, with motor dysfunction being the most prominent clinical feature. The severity of the clinical manifestations ranges from mild to severe. Patients with severe and intermediate phenotypes may present with infantile parkinsonism that differs in a number of aspects from the parkinsonism in nigrostriatal degeneration. Analysis of monoamine metabolites and pterins in spinal fluid assists in the diagnosis of these disorders. Treatment options include tetrahydrobiopterin supplementation, L: -dopa, 5-hydroxytryptophan, and medications that potentiate monoamine transmission. Response to treatment is variable.

[Determination of brain natriuretic peptide in patients undergoing different haemodiafiltration techniques]

IB-type natriuretic peptide is a cardíac neurohormone secreted by the cardíac ventricules in response to ventricular dilatation so plasma BNP level correlate with left ventricular mass and dysfunction. Dialysis patients have much greater levels of BNP due to the volume overload and because of reduced renal clearance. The aim of this study was to mesure and compare the BNP levels in three groups of patients who received different hemodiafiltration techniques: Daily online hemodiafiltration (HDFOLd), on-line hemodiafiltration (HDFOL) and low convective volume hemodiafiltration (HDF). Fifteen patients were included, five in each group. Pre and postdialysis BNP leves were measured during 8 weeks. The measure was done at the beginning of the week (long period), and at the end (short period), in order to study if there were significative differences between techniques and periods. We found significative differences between predialysis BNP levels in the short period (BNPpreC) and the long period (BNPpre-L). We also found significative differences with the posdialysis BNP in both periods; BNPpre- L vs. BNPpos-L (1069+/-1031 vs. 612 +/- 540). After comparing the three techniques the study showed significative differences between BNPpreC in HDF and HDFOL compared with HDFOld. And also after dialysis between BNPpos-C in HDFOLd compared with the other techniques.

CONCLUSION

Although previous papers have shown that BNP levels have limited potential for assessment of hydration in hemodialysis patients, in this study our data demonstrate that after dialysis BNP levels decline in a significative way in the long and short period and we have found that patients on daily hemodialysis show lower BNP levels, and maybe this could be explained because daily on-line haemodiafiltration patients had lower weight rise between dialysis sessions and also better haemodynamic tolerance.

Penetration and growth of DPPC/DHPC bicelles inside the stratum corneum of the skin

The effect of dipalmitoyl phosphatidylcholine (DPPC)/dihexanoyl phosphatidylcholine (DHPC) bicelles on the microstructure of pig stratum corneum (SC) in vitro was evaluated. The physicochemical characterization of these nanoaggregates revealed small disks with diameters around 15 nm and a thickness of 5.4 nm. Upon dilution, the bicelles grow and transform into vesicles. Cryogenic scanning electron microscopy (cryo-SEM) images of the SC pieces treated with this system showed vesicles of about 200 nm and lamellar-like structures in the intercellular lipid areas. These vesicles probably resulted from the growth and molecular rearrangement of the DPPC/DHPC bicelles after penetrating the SC. The presence of lamellar-like structures is ascribed to the interaction of the lipids from bicelles with the SC lipids. The bicellar system used is suitable to penetrate the skin SC and to reinforce the intercellular lipid areas, constituting a promising tool for skin applications.

[Kinetic of calcium, phosphate, magnesium and PTH variations during hemodiafiltration]

Hemodiafiltration (HDF) is a technique resulting from coupling of diffusive and convective transport and thereby increase the elimination of small and middle molecules. However, may induce a convective loss from others substances such as calcium and magnesium. The aim of this study was to evaluate the effects of Ultrafiltration on the kinetics of calcium, phosphate, magnesium and parathyroid hormone. A total of thirteen patients (7 males and 6 females) on hemodialysis, were studied. Each patient was randomly dialyzed with the same dialysate calcium concentration and three different ultrafiltration rate. Schedule A: High flux hemodialysis, schedule B: HDF with 10% of weight body and schedule C: HDF with 20% of weight body. The others parameters were kept identical. Total Ultrafiltration was 2,6+/-0,9 L (9,78+/-3,78 ml/min) in A, 9,3+/-1,7 L (34,54+/-6,22 ml/min) in B and 16,3+/-3,3 L (60,94+/-12,63 ml/min) in C. Replacement fluid during dialysis was 6,85+/-1,42 and 13,65+/-2,9 L. in C and C respectively. Postdialysis total,ionized calcium and magnesium were significantly lower in schedules B and C versus A. PTH levels did not differ significantly. However, PTH changes during dialysis was -36.6+/-38.6%, 6.3+/-69.8% and 32.2+/-63.2% in A, B and C, respectively (p<0.05 A vs. C). A significant inverse correlation was found between total Ultrafiltration and postdialysis levels of total calcium (r:-0.56, p<0.001), ionized calcium (r:-0.65, p<0.001) and magnesium (r:-0.47, p<0.01). No differences were observed in pre and postdialysis phosphate levels, neither mass transfer and clearance of phosphate. We concluded that high ultrafiltration flow rates and substitution fluid without divalent cations induces a negative calcium and magnesium balance. These changes may stimulate PTH secretion during HDF. This technique did not resulted in a higher clearance or phosphate removal.

[Oxidative stress analysis in patients on hemodiafiltration on-line]

Patients with chronic renal disease have a very high mortality due to cardiovascular disease. However, the traditional risk factors are not the only one explanation. Nowadays, there are new risk factors becoming, and one of these is the oxidative stress. Besides today we know that when these patients receive haemodialysis are being exposed to an additional oxidative stress. The aim of this study was to measure and to compare the degree of oxidative stress in two groups of patients on different dialysis techniques: a) On-Line Haemodiafiltration three times / week (OL-HDF). b) Daily Om-Line haemodiafiltration ( six times / week ) ( dOL-HDF) We studied 9 patients with chronic renal disease stage 5 on hemodialysis. They all were men, with a medium age of 72,5 +/- 6 years. Five patients were on dOL-HDFand four on tOL-HDF. Glutathione (GSH) concentration of patients on dOL-HDF before dialysis was 742+/- 153 nmol/ml and post-dialysis de 878+/- 223. Blood GSSG concentration before and after dialysis was 34+/- 14 nmol/ml y 137+/- 74 nmol/ml (p< 0,03). GSSG/GSH ratio pre-dialysis was 58+/-10 and post-dialysis 169+/-65 ( p < 0,03). In OL-HDF group GSSG concentration and the ratio GSSG/GSH also increased in a significative way from 99+/-45 nmol/ml to 179+/-66 nmol/ml, and from 161+/- 99 to 337+/-143 ( p<0,05). We also found differences in pCR concentrations between both groups; 3+/-1,4 g/l in dOL-HDF and 8,75+/-5,8 g/l in HDF OL. (p< 0,05). We did not find differences between xatine-oxidase activity before and after hemodialysis and between groups. In conclusion, patient with terminal chronic renal disease on OL-HDF receive an additional load of oxidative stress, as the increase in GSSG/GSH ratio in both groups shows. However patients on dHDF-OL shows low ratios GSSG/GSH post-hemodialysis and low pCR concentrations, and maybe this could be explained because daily on line haemodiafiltration improves purification of inflammatory mediators. Clue words: Hemodialysis, oxidative stress, glutathione, gssg/gsh ratio, xantine oxidasa.

Effect of sodium dodecyl sulfate at different hydration conditions on dioleoyl phosphatidylcholine bilayers studied by grazing incidence X-ray diffraction

The effect of the surfactant content and hydration conditions in the phases of dioleoyl phosphatidylcoline (DOPC)/sodium dodecyl sulfate (SDS) mixtures was studied. To this end, surface X-ray diffraction experiments have been performed on bilayers of the mixtures deposited on hydrophobic silicon wafers by dip coating. To investigate the effect of relative humidity (RH) on bilayer organization, a humidity chamber with dry-wet air control was used, and RH values were fixed between 1 and 65%. Our results showed, in addition to the lamellar phase, a rhombohedral phase in mixtures at low hydration conditions (RH < 30%). The d spacing between lamellae increased with the RH and SDS content. This fact could be associated with a swelling effect that is probably due to the localization of water molecules between the polar headgroups of the DOPC and SDS forming the bilayers. The electron-density profiles calculated by Fourier reconstruction of the lamellar stacking for the different samples also confirmed this fact. In addition, the increase in d spacing could be related to the increase in the hydrophilic character of the mixture when the SDS content increases. The rhombohedral phase was more clearly observed in mixtures with high SDS content. Thus, the stalk structure of the rhombohedral phase could be facilitated because of the SDS contribution to inverse structures.

Study and formation of vesicle systems with low polydispersity index by ultrasound method

The formation of liposomes with low polydispersity index by application of ultrasounds was investigated considering methodology specifications such as sonication time and sonication power. Phosphatidylcholine (PC) liposomes were formed by the evaporation-hydration method. The vesicles were sonicated using several sonication conditions. The liposomes were then characterized by dynamic light scattering (DLS) and freeze-fracture electron microscopy (FFEM). Correlation functions from DLS were treated by cumulants method and GENDIST to obtain the mean radius and polydispersity index. These calculations allowed to fix an optimal sonication time (3000 s) and a useful interval of ultrasound power between 39 and 91 W. DLS and FFEM results confirmed that vesicle size, lamellarity and the polydispersity index decreased with the increase of sonication power. Thus, we propose a systematic method to form liposomes in which the physical characteristics of the vesicles may be controlled as a function of sonication time and power.

[Estimation of the cost in the farmacologic treatment of chronic renal failure]

The prevalence and incidence of end stage renal disease has increased considerably in the past years. We know that the cost of treatment of these patients is high. Limited information exists on care resource utilization for maintenance of patients before the initiation of replacement therapy. The purpose of this study is determine the cost of pharmaceutic treatment during the predialysis phase. Pharmacy cost was analyzed for 200 patients controlled on outpatient nephrology department. The mean age was 72.4 years, 59% were males, and the comorbidity distribution was: hypertension 87%, hyperlipidemia 56% and diabetes 35%. The per-patient-per-month charges were 215.45 Euro, with a continous increase from 84.64 Euro on stage 1 to 352.59 Euro on stage 5 of chronic kidney disease. Erythropoiesis stimulants were reponsible of 46.5% of these cost. The most frequent prescribed medications were antihypertensive drugs, statins and iron preparations. Patients with end stage renal disease generate significant cost during the predialysis period. The limited resources, and the growth of health care expeditures, particulary the spending for prescriptions drugs, are two of the major problems for Health Care Systems. A better knowledge of the associated costs to the treatment of these patients will help us to increase our efficiency.

The Effect of Molecular Shape on the Thermotropic Liquid Crystal Behavior of Monolauroylated Amino Acid Glyceride Conjugates

Monoacylglycerol amino acid conjugates constitute a novel class of specific biocompatible surfactants that can be considered analogues to partial glycerides and lysophospholipids. They consist of one aliphatic chain and one polar head, i.e., the amino acid, linked through a glycerol moiety. In a previous work, we synthesized monolauroylated amino acid glyceride conjugates, 1-O-lauroyl-rac-glycero-3-O-(N(alpha)-acetyl-L-amino acid), changing the amino acid headgroup systematically: arginine (compound 2), aspartic acid (compound 3), glutamic acid (compound 4), asparagine (compound 5), glutamine (compound 6), and tyrosine (compound 7), to elucidate the structure-properties relationship governing the occurrence of their polymorphism. The thermotropism of the new compounds was measured with polarizing light microscopy, differential scanning calorimetry, and X-ray diffraction and compared with the classical monoglyceride rac-1-lauroylglycerol (compound 1). The experiments were performed for a sequence of heating, cooling, and reheating scans. The results showed that compounds 1-6 exhibit a thermotropic smectic phase. As a consequence, the substitution of the polar head did not engender any curvature into the system, which might lead to the formation of cubic or columnar phases. Interestingly, liquid crystalline phases were not found in the case of compound 7. Small-angle X-ray diffraction data in the gel phase revealed that the substitution of the polar head by the different amino acid structures did not modify significantly the lamellar repeat distance relative to that of the reference one. The observed area per molecule, however, was larger for the new compounds. Consequently, interdigitation was promoted in compounds 2-7. The diffraction patterns were analyzed in terms of electron density profiles, using a modified Caillé theory plus a Gaussian electron density representation (MCG method) on X-ray diffraction data.

[An evaluation of costs in nephrology by means of analytical accounting system]

BACKGROUND

The analytical accounting is a countable technique directed to the evaluation, by means of pre-established criteria of distribution, of the internal economy of the hospital, in order to know the effectiveness and efficiency of Clinical Units. The aim of this study was to analyze the activity and costs of the Nephrology Department of General Hospital of Castellón.

METHODS

Activity of Hospitalization and Ambulatory Care, during 2003 was analysed. Hospitalization discharges were grouped in DGR and the costs per DGR were determinated.

RESULTS

Total costs Hospitalisation and Ambulatory Care were 560.434,9 and 146.317,8 Euros, respectively. And the costs of one stay, one first outpatient visit and maintenance visit were 200, 63, and 31,6 Euros, respectively. Eighty per cent of the discharges were grouped in 9 DGR and DRG number 316 (Renal Failure) represented 30% of the total productivity. Costs of DGR 316 were 3.178,2 Euros and 16% represented laboratory cost and costs of diagnostic or therapeutic procedures.

CONCLUSION

With introduction of analytical accounting and DGR system, the Nephrology Departments can acquire more full information on the results and costs of treatment. These techniques permits to improve the financial and economic performance.

Aromatic L-amino acid decarboxylase deficiency: clinical features, treatment, and prognosis

BACKGROUND

Deficiency of aromatic L-amino acid decarboxylase (AADC) is associated with severe developmental delay, oculogyric crises (OGC), and autonomic dysfunction. Treatment with dopamine agonists and MAO inhibitors is beneficial, yet long-term prognosis is unclear.

OBJECTIVE

To delineate the clinical and molecular spectrum of AADC deficiency, its management, and long-term follow-up.

RESULTS

The authors present six patients with AADC deficiency and review seven cases from the literature. All patients showed reduced catecholamine metabolites and elevation of 3-O-methyldopa in CSF. Residual plasma AADC activity ranged from undetectable to 8% of normal. Mutational spectrum was heterogeneous. All patients presented with hypotonia, hypokinesia, OGC, and signs of autonomic dysfunction since early life. Diurnal fluctuation or improvement of symptoms after sleep were noted in half of the patients. Treatment response was variable. Two groups of patients were detected: Group I (five males) responded to treatment and made developmental progress. Group II (one male, five females) responded poorly to treatment, and often developed drug-induced dyskinesias.

CONCLUSIONS

The molecular and clinical spectrum of AADC deficiency is heterogeneous. Two groups, one with predominant male sex and favorable response to treatment, and the other with predominant female sex and poor response to treatment, can be discerned.

A synthetic alternative to natural lecithins with antimicrobial properties

Two soft biocompatible cationic surfactants from the amino acid arginine, 1,2-dilauroyl-3-acetylarginyl-rac-glycerol (1212RAc) and 1,2-dimirystoyl-3-acetylarginyl-rac-glycerol (1414RAc), were prepared. Their physicochemical properties show that they can be classified as multifunctional surfactants with self-aggregation behaviour comparable to that of short-chain lecithins. The two surfactants can simultaneously stabilise water-in-oil (W/O) droplets and oil-in-water (O/W) droplets, forming multiple emulsions. They have antimicrobial activity similar to that of conventional cationic surfactants and are as harmless as amphoteric betaines. These surfactants constitute an interesting alternative to the diglycerides and lecithins in formulations that require antimicrobial properties.

Effect of the electrostatic charge on the mechanism inducing liposome solubilization: a kinetic study by synchrotron radiation SAXS

The anionic surfactant sodium dodecyl sulfate (SDS) was used to induce the initial steps of the solubilization of liposomes. The structural transformations as well as the kinetics associated with this initial period were studied by means of time-resolved small-angle X-ray scattering (SAXS) using a synchrotron radiation source. Neutral and electrically charged (anionic and cationic) liposomes were used to investigate the effect of the electrostatic charges on the kinetics of these initial steps. The mechanism that induces the solubilization process consisted of adsorption of surfactant on the bilayers and desorption of mixed micelles from the liposomes surface to the aqueous medium. In all cases the time needed for desorption of the first mixed micelles was shorter than that for complete adsorption of the surfactant on the liposomes surface. The present work demonstrates that adsorption of the SDS molecules on negatively charged liposomes was slower and release of mixed micelles from the surface of these liposomes was faster than for neutral liposomes. In contrast, in the case of positively charged liposomes, the adsorption and release processes were, respectively, faster and slower than those for neutral vesicles.

[Outcome of tunneled hemodialysis catheters as permanent vascular access]

Tunneled cuffed hemodialysis catheters (THC) are developed as a means of short hemodialysis access while a more permanent form of access are maturing. The aim of this study is to investigate the effectiveness, survival and complications of the THC used for long-term vascular access.

METHODS

In a retrospective study we looked at 42 THC inserted between November 2000 and October 2003, in 40 elderly patients, with systemic disease or when other vascular access was not possible.

RESULTS

Procedural complications occurred in 5 cases (11.9%), which included: local haemorrhage (3), hemothorax (1) and one fatal venous tear. 6 catheters (14.2%) were removed due to complications (non-function 3 and bacteraemia 3). The total incidence of THC related infections was 0.18 episodes/1,000 catheters-days. Patients were followed up for a mean 379 days (range 1-1,140) and a total of 15,946 catheter-days. Qb and KT/V achieved at one month were 278.3 +/- 34.1 ml/min and 1.48 +/- 0.27 respectively. At the end of the follow-up, 23 patients (54.7%) were alive with catheter functioning. One, three and twelve months survival was 90.4%, 73.1% and 59.5% respectively.

CONCLUSION

The THC may be a useful alternative permanent vascular access for hemodialysis patients when others vascular access are not possible.

Formation and properties of miniemulsions formed by microemulsions dilution

Mini-emulsions have been formed in quaternary systems water/hexanol/sodium dodecyl sulfate/decane by dilution of a microemulsion with an excess of water. We have investigated systematically the effect of composition variables in the droplet size and Ostwald Ripening rate. This droplet size has been investigated by using dynamic light scattering of samples submitted to further dilution in water. According to the dynamic light scattering results, the initial droplet size depends on the initial microemulsion water content, the larger the initial water concentration, the smaller the initial droplet size. This is probably related to the structure of the initial phase. The rate of Ostwald Ripening depends on the final surfactant concentration as expected for differences in interfacial tension. At high surfactant and dispersed phase contents, instability due to flocculation has been observed. Other experiments in which a fifth component (a more hydrophobic oil) was added to slow down Ostwald Ripening showed an initial droplet size increasing comparable to the systems without additive but after a relatively long time of approximately 2 h, a decrease was observed.

[Ciprofloxacin-induced vasculitis with cutaneous and renal involvement]

Quinolone antibiotics are frequently used in the practice of medicine. Nephrotoxic side effects related to the use of quinolones are uncommon. We report a patient in treatment with ciprofloxacin who presented with purpuric skin lesions and alteration of renal function. We review these antibacterial agents with special attention on associated adverse reactions, and present-day experience with the newer quinolone antibiotics.

Effects of inhaled glaucine on pulmonary responses to antigen in sensitized guinea pigs

The alkaloid (S)-(+)-1,2,9,10-tetramethoxyaporphine (glaucine) is a phosphodiesterase 4 inhibitor with bronchodilator and anti-inflammatory activity in vitro. In this study, we examined the in vivo effects of glaucine on an animal model of asthma. In ovalbumin sensitized guinea pigs, inhaled glaucine (10 mg ml(-1), 3 min) inhibited the acute bronchoconstriction produced by aerosol antigen (antigen response was 256+/-42 and 95+/-14 cm H(2)O l(-1) s(-1) in control and glaucine-treated animals, respectively; P<0.05). Pretreatment with glaucine (10 mg ml(-1), 10 min inhalation, 30 min pre- and 3 h post-antigen exposure) markedly reduced airway hyperreactivity to histamine, eosinophil lung accumulation, and increased eosinophil peroxidase activity in bronchoalveolar lavage fluid 24 h after exposure of conscious guinea pigs to aerosol antigen. In addition, inhaled glaucine (5-10 mg ml(-1), 3 min) inhibited the microvascular leakage produced after inhaled antigen at all airway levels. These data support the potential interest of phosphodiesterase 4 inhibitors in asthma treatment.

Clinical and molecular heterogeneity in very-long-chain acyl-coenzyme A dehydrogenase deficiency

Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is an increasingly recognized defect of mitochondrial fatty acid beta-oxidation manifesting with episodes of metabolic decompensation or isolated recurrent myoglobinuria. In this report the clinical, biochemical, and molecular studies in a series of five patients (four Italian and one Spanish) with this disorder are discussed. Biochemical studies included the determination of fibroblast substrate oxidation rates and enzyme activity and Western blot analysis of VLCAD protein. Molecular analysis was performed by sequencing the VLCAD gene from the genomic DNA. Clinical features were within the spectrum previously reported. Four patients presented in infancy or childhood with episodes of severe metabolic decompensation and dicarboxylic aciduria. Two exhibited cardiomyopathy. The fifth patient presented with isolated recurrent rhabdomyolysis, with no cardiomyopathy or dicarboxylic aciduria. In all patients a significant loss of VLCAD activity associated with a marked reduction of VLCAD protein levels occurred. Molecular analysis disclosed one novel missense mutation (Cys437Tyr) and four previously reported mutations, including two missense substitutions (Phe418Leu and Arg419Trp), a single amino acid deletion (Lys258del), and one splice site mutation (IVS8-C(-2)), which was present in all four Italian patients. All patients exhibited compound heterozygosity. The phenotypic variability and the high genotypic heterogeneity of this hereditary metabolic disorder is reported.

Bronchodilator and anti-inflammatory activities of glaucine: In vitro studies in human airway smooth muscle and polymorphonuclear leukocytes

1. Selective phosphodiesterase 4 (PDE4) inhibitors are of potential interest in the treatment of asthma. We examined the effects of the alkaloid S-(+)-glaucine, a PDE4 inhibitor, on human isolated bronchus and granulocyte function. 2. Glaucine selectively inhibited PDE4 from human bronchus and polymorphonuclear leukocytes (PMN) in a non-competitive manner (Ki=3.4 microM). Glaucine displaced [3H]-rolipram from its high-affinity binding sites in rat brain cortex membranes (IC50 approximately 100 microM). 3. Glaucine inhibited the spontaneous and histamine-induced tone in human isolated bronchus (pD2 approximately 4.5). Glaucine (10 microM) did not potentiate the isoprenaline-induced relaxation but augmented cyclic AMP accumulation by isoprenaline. The glaucine-induced relaxation was resistant to H-89, a protein kinase A inhibitor. Glaucine depressed the contractile responses to Ca2+ (pD'2 approximately 3.62) and reduced the sustained rise of [Ca2+]i produced by histamine in cultured human airway smooth muscle cells (-log IC50 approximately 4.3). 4. Glaucine augmented cyclic AMP levels in human polymorphonuclear leukocytes challenged with N-formyl-Met-Leu-Phe (FMLP) or isoprenaline, and inhibited FMLP-induced superoxide generation, elastase release, leukotriene B4 production, [Ca2+]i signal and platelet aggregation as well as opsonized zymosan-, phorbol myristate acetate-, and A23187-induced superoxide release. The inhibitory effect of glaucine on superoxide generation by FMLP was reduced by H-89. 5. In conclusion, Ca2+ channel antagonism by glaucine appears mainly responsible for the relaxant effect of glaucine in human isolated bronchus while PDE4 inhibition contributes to the inhibitory effects of glaucine in human granulocytes. The very low PDE4/binding site ratio found for glaucine makes this compound attractive for further structure-activity studies.

Diffraction-like effects in a highly concentrated W/O emulsion: a PFG NMR study

Diffraction-like effects have been observed by applying pulsed field gradient (PFG) nuclear magnetic resonance (NMR) to a highly concentrated water-in-oil (W/O) emulsion, made up of the nonionic surfactant C12E4 [CH3(CH2)11(OCH2CH2)4OH], n-decane, and brine [1 wt% NaCl(aq) solution]. The pulsed field gradient NMR data show one pronounced maximum and the shoulder of a second maximum in the attenuation curve of the NMR signal from water, the so-called Bragg interference peaks. From the diffraction-like peaks, the average distance (center to center) between the emulsion droplets can be obtained, in this case related to the average size of an emulsion droplet. Furthermore, we note that the long-term stability of the emulsion can be followed by pulsed field gradient NMR.

Is visual anticipation of collision during self-motion related to perceptual style?

We have previously shown that during self-motion in car driving situations, the perception of another car's trajectory relies both on global visual information such as the optical flow field, and on local visual information such as the optical motion of the other car and the relative optical motion of the other car with respect to fixed elements in the environment. Here, we studied the environmental factors that contribute to perceptual judgements in relation to the observer's perceptual style (visual-field dependence vs. visual-field independence). In an experiment, observers were presented with visual scenes corresponding to the curvilinear self-motion of a driver approaching an intersection where another vehicle was arriving perpendicularly. The factors manipulated were the presence or absence of a spatial reference point (road sign near the intersection), environmental complexity ("road" or "spot" scenes), and the degree of field dependence/independence. Nine field-independent (FI) subjects and seven field-dependent (FD) subjects were asked to predict whether the other vehicle would reach the intersection before or after they would. Their responses were analyzed. Overall, subjects' judgements were more accurate with road environments and with a road sign, suggesting that the relative motion of the other vehicle with respect to fixed elements in the environment provides additional useful information. FI subjects were significantly more accurate than FD subjects, suggesting that the former are better at picking up relevant dynamic information in a complex environment.

Very-long-chain acyl-coenzyme A dehydrogenase deficiency in a child with recurrent myoglobinuria

A 9-year-old boy had recurrent episodes of myoglobinuria and normal urinary organic acid profile. Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency was detected biochemically in cultured skin fibroblasts and confirmed by Western blot analysis. The patient had a distinctive plasma fatty-acid profile, which was present even between attacks. Early diagnosis of this disorder is important because of the apparently protective effect of an appropriate dietary regimen.

Bronchodilator and anti-inflammatory activities of SCA40: studies in human isolated bronchus, human eosinophils, and in the guinea-pig in vivo

There is currently interest in the use of inhibitors of cyclic nucleotide phosphodiesterases (PDE) as potential anti-asthma agents. In this study we examined the effects of SCA40 (6-bromo-8-methylaminoimidazol-[1,2-a] pyrazine-2-carbonitrile), a preferential inhibitor of PDE 3 also endowed with PDE 4 and 5 inhibitory activities, on isolated bronchus and eosinophil functions and in an animal model of asthma. SCA40 (1 nM-0.1 mM) produced concentration-dependent inhibition of spontaneous and stimulated tone of human isolated bronchus and reached a maximal relaxation similar to that of theophylline (3 mM). The potency (-log EC50 values) of SCA40 against spontaneous tone (6.52 +/- 0.10) was greater than against tone raised by equieffective concentrations (approximately 70%) of histamine (5.76 +/- 0.06), leukotriene C4 (5.44 +/- 0.11), and acetylcholine (4.98 +/- 0.09). In the presence of cytochalasin B, the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP; 0.5 microM) induced leukotriene C4 production in human eosinophils isolated in discontinuous metrizamide gradients. The production of leukotriene C4 was inhibited by SCA40 in a concentration-related fashion (-log IC50 = 6.04 +/- 0.20; n = 6). Rolipram, a selective PDE 4 inhibitor, was also effective (-log IC50 = 7.29 +/- 0.32) but the selective PDE 3 inhibitor SKF94120 was scarcely effective (< 10% inhibition for 10 microM). In ovalbumin sensitized guinea-pigs, SCA40 (1 mg kg(-1), i.p.) given 30 min before antigen challenge significantly inhibited the acute bronchoconstriction produced by aerosol antigen (5 mg ml(-1), 30 s) (antigen response was 185 +/- 13 and 91 +/- 21 cmH2O l(-1) s(-1) in control and SCA40-treated animals, respectively, P < 0.05). Pretreatment with SCA40 (1 mg kg(-1), i.p., 30 min pre- and 3 h post-antigen exposure) prevented airway hyperreactivity to histamine which developed 24 h after exposure of conscious guinea-pigs to aerosol antigen. Eosinophil lung accumulation that accompanied airway hyperreactivity was also inhibited by SCA40 (from 6.15 +/- 0.86 in control to 1.27 +/- 0.27 in treated animals; expressed as eosinophils x 10(6); P < 0.05). SCA40 (1 mg kg(-1), i.p.) also inhibited the microvascular leakage produced after inhaled antigen (5 mg ml(-1), 30 s) at all airway levels. The haemodynamic effects of SCA40 (1 mg kg(-1), i.p.) consisted of a rapid decrease (peak at 5 min) in mean arterial blood pressure (-39.4 +/- 2.4%) and tracheal mucosal blood flow (-13.5 +/- 2.0%) that slowly recovered with time. These data support previous work showing that PDE inhibition results in antispasmogenic and anti-inflammatory effects. SCA40 was effective in vitro and in vivo and these effects are probably related to its activity as a mixed PDE inhibitor.

Deficient muscle carnitine transport in primary carnitine deficiency

Primary carnitine deficiency is associated with deficient blood and tissue carnitine concentrations. The clinical syndrome is dominated by heart and skeletal muscle symptoms, and the clinical response to oral carnitine supplementation is life-saving. Carnitine uptake has been shown to be defective in cultured skin fibroblasts and leukocytes obtained from patients with this condition. We report a new case of primary carnitine deficiency and offer direct evidence consistent with an impairment of carnitine uptake in differentiating muscle culture. The patient presented with severe and progressive cardiomyopathy and moderate proximal limb weakness. Plasma and muscle carnitine levels were very low, and the maximal rate of carnitine transport in cultured fibroblasts was deficient. An asymptomatic sister with intermediate levels of carnitine in plasma showed partially deficient carnitine uptake in fibroblasts, indicating heterozygosity. The patient's condition improved dramatically with oral carnitine therapy. Further studies were performed in cultured muscle cells at different stages of maturation, which demonstrated deficient maximal rates of carnitine uptake. Our findings are consistent with the concept that primary carnitine deficiency is the result of a generalized defect involving carnitine transport across tissue membranes.