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R Azar

Publications and source records attributed to R Azar.

At least 19 recordsLinked to original sources
PubMed2001

Comparative study of the leachability of di(2-ethylhexyl) phthalate and tri(2-ethylhexyl) trimellitate from haemodialysis tubing.

The leachability of both Di(2-ethylhexyl) phthalate (DEHP) and Tri(2-ethylhexyl) trimellitate (TEHTM) or Trioctyl trimellitate (TOTM) from haemodialysis tubing was investigated in 20 patients with chronic renal failure undergoing maintenance haemodialysis. The blood tubing made of common polyvinyl chloride (PVC) plasticized with DEHP (group 1 patients) were replaced with tubing plasticized with TOTM-DEHP (group 2 patients). The patient blood obtained from the inlet and the outlet of the dialyzer was analyzed during a 4 h-dialysis session. Thus, the circulating concentrations of both DEHP and TOTM resulting from the release from dialyzer tubes were estimated using High-performance Liquid chromatograph (HPLC). With the common PVC-DEHP blood tubing, a DEHP quantity of 122.95+/-33.94 mg was extracted from tubing during a single dialysis session (ranging from 55 to 166.21 mg). During the same period, the total amounts of DEHP retained by the patients were 27.30+/-9.22 mg (ranging from 12.50 to 42.72 mg). As for blood tubing plasticized with TOTM-DEHP, 41.80+/-4.47 mg of DEHP and 75.11+/-25.72 mg of TOTM were extracted. During the same period, the amounts of DEHP and TOTM retained by the patients were 3.42+/-1.37 mg and 4.87+/-2.60 mg, respectively. The extraction rate both plasticizers was correlated with serum lipid content (cholesterol+triglyceride) (r(2)=0.75 for DEHP and r(2)=0.64 for TOTM). In the present investigation, less TOTM and DEHP were apparently released from haemodialysis tubing plasticized with TOTM-DEHP than DEHP released from haemodialysis tubing plasticized with DEHP only. TOTM seems to be a superior alternative to DEHP for use in medical devices because of its potential lower leachability. To recommend it as an alternative plasticizer, its possible toxicity towards human body should be investigated before it can be used routinely. However, patients undergoing haemodialysis using tubing plasticized with DEHP only are regularly exposed to non negligible amounts of DEHP. In view of several biological effects previously reported, it is time to reconsider the use of DEHP only as a plasticizer.

Adult↗
PubMed2001

Factors influencing survival in hemodialysis patients aged older than 75 years: 2.5-year outcome study.

The incidence of malnutrition is widely held to be greater in the elderly, but this specific factor has not been extensively studied in elderly dialysis patients. In a 30-month follow-up prospective study, we evaluated the role of nutrition on the outcome of 290 stable hemodialysis (HD) outpatients aged older than 75 years followed up in 20 French HD centers (167 men, 123 women; age, 79.8 +/- 4.2 years; previous time on dialysis, 41 +/- 38 months). On the same day in January 1996, predialysis and postdialysis blood samples were collected according to recommended procedures for dialysis quantification. Normalized protein catabolic rate, dialysis adequacy parameters, and estimation of lean body mass (LBM; expressed as observed/expected LBM values [obs/exp LBM]) were computed from predialysis and postdialysis urea and creatinine levels. Overall survival rates were 80% and 65% after 1 and 2 years of follow-up, respectively, and were significantly less in patients with the lower quartile of obs/exp LBM. In univariate analysis using the Cox proportional hazards model, survival was significantly influenced by age, albumin level, prealbumin level, body mass index, and diabetes, but not by sex, Kt/V, duration of dialysis, cholesterol level, hemoglobin level, or obs/exp LBM. In multivariate analysis, no variable remained significant. Cardiovascular mortality accounted for 52.1% of the patient deaths. We conclude that in elderly HD patients, malnutrition influences overall survival despite adequate dialysis treatment.

Aged↗
PubMed2001

Influence of nutritional factors and hemodialysis adequacy on the survival of 1,610 French patients.

Nutritional factors and dialysis adequacy are associated with outcome in hemodialyzed patients, but their relative contribution remains controversial, particularly when dialysis adequacy complies with current recommendations (Kt/V >1.2). Survival, clinical, and nutritional data from a cohort of prevalent 1,610 patients treated by hemodialysis in 20 centers in France have been collected over a 2.5-year period, from January 1996 to July 1998. Data including age, sex, cause of end-stage renal disease (ESRD), clinical outcome, time on dialysis, body mass index (BMI), blood levels of midweek predialysis albumin, prealbumin, and bicarbonate were analyzed. Normalized protein catabolic rate (nPCR), dialysis adequacy parameters, and estimation of lean body mass (LBM) from creatinine generation were computed from pre- and postdialysis urea and creatinine levels. The characteristics of the patients were as follows: age 59.6 +/- 16.5 years, 58.8% males, 11% of diabetics, time on dialysis 63.2 +/- 64.5 m. Weekly dialysis time was 12.18 +/- 1.78 hrs, Kt/V 1.34 +/- 0.34, nPCR 1.10 +/- 0.35 g/kg body weight/day. Albumin concentration was 39.4 +/- 5.3 g/L, prealbumin was 0.33 +/- 0.09 g/L, BMI was 23.0 +/- 4.5 kg/m(2). Overall survival was 89.7% +/- 0.8% and 78.4% +/- 1.1% after 1 and 2 years. In the Cox proportional hazard model, survival was significantly influenced by age, the presence of diabetes, and by concentrations of albumin and prealbumin, but not by other variables, including Kt/V and urea reduction ratio. These results indicate that nutritional protein concentrations were predictive of dialysis outcome, whereas variables reflecting actual body composition and dialysis dose were not. Furthermore, in this well-dialyzed population, dialysis adequacy had no influence on survival. In conclusion, when adequacy targets are met in hemodialyzed patients, survival is mainly dependent on age and nutritional status. Efforts should be focused on the most efficient ways to maintain nutritional status in these patients.

Adult↗
PubMed2000

High-performance liquid chromatographic determination of naltrexone in plasma of hemodialysis patients.

A simple, sensitive, selective and reliable reversed-phase high-performance liquid chromatographic (HPLC) method with UV detection is described for the determination of naltrexone in plasma samples. Naltrexone and the internal standard, naloxone, were isolated from plasma either with a liquid-liquid extraction method using ethyl acetate or with a solid-phase extraction method using Sep-Pack C18 cartridge before chromatography. The extracts were dried under a stream of nitrogen and the samples were reconstituted in the mobile phase, then 20 microL were injected on a Waters Symmetry C18 column (5 microm particle size, 4.6 x 150 mm). The mobile phase consisted of 0.06% triethylamine (pH 2.8)-acetonitrile (92:8, v/v) pumped at 1 mL/min. The peak-area ratio versus plasma concentration was linear over the range of 10-500 ng/mL and the detection limit was less than 8 ng/mL. Quantification was by ultra-violet detection at 204 nm. The present method was applied to the determination of the plasma concentration of naltrexone in dialyzed patients. Patients (n = 8) with severe generalized pruritus received 50 mg of naltrexone orally per day for 2 weeks. The variability in the therapeutic response in treated patients required plasma concentration investigations of this opioid antagonist.

Chromatography, High Pressure Liquid↗
PubMed1999

Nutritional status of haemodialysis patients: a French national cooperative study. French Study Group for Nutrition in Dialysis.

BACKGROUND: Despite the severity and the prognosis value of undernutrition in haemodialysed patients, no large study is available as yet in Europe. Hence, this French National Cooperative Study aimed to determine the prevalence of undernutrition and its relationship to dialysis efficacy. METHODS: Nutritional status was determined in 7123 patients (i.e. one-third of the French haemodialysis population) using body mass index (BMI), predialysis haemoglobin, albumin, pre-albumin, cholesterol, and also normalized protein catabolic rate (nPCR) and lean body mass (LBM) calculated from pre- and postdialysis urea and creatinine. Dialysis treatment was estimated from weekly dialysis time and KtV determination. RESULTS: Dialysis time was 12.4+/-2.7 h/week and KtV 1.36+/-0.36. BMI was below 20 kg/m2 in 24% and the observed/expected LBM ratio below 90% in 62%. Albumin, pre-albumin and nPCR were below the high-risk thresholds of 35 g/l, 300 mg/l and 1g/kg/day in 20%, 36% and 35% of patients, respectively. Pre-albumin was the most representative nutritional parameter. Albumin, pre-albumin and LBM correlated with nPCR. A dialysis time above 12 h/week was associated with higher BMI, albumin, pre-albumin and LBM. LBM was higher in patients with a KtV value >1.1. CONCLUSION: This study showed life-threatening undernutrition in 20-36% of the studied population, according to nutritional parameters. Protein intake (estimated by nPCR) and dialysis efficacy (estimated by dialysis time and KtV) appeared to be major determinants of nutritional status in this population.

Adult↗
PubMed1998

Molecular epidemiology of adenovirus type 7 in Israel: identification of two new genome types, Ad7k and Ad7d2.

The molecular epidemiology of Adenovirus type 7 in Israel was investigated. Fifty-seven adenovirus isolates identified as serotypes 7 or 7a which were recovered from patients in Israel between 1968 and 1995 were analyzed by restriction enzymes digestion using BamHI for primary discrimination and identification of genome types and by six additional enzymes: BstEII, HpaI, BglI, BglII, BclI, and XbaI for confirmation and determination of genomic subtypes. Four digestion patterns were identified with BamHI; one of them was new. Using BstEII, two patterns were obtained, one of them new. Digestion with the other five enzymes yielded known patterns. The analysis revealed four different genomic types and subtypes, which circulated in Israel in different years: subtype 7a1; type 7b, a type with a new BamHI pattern which was designated type 7K, and a subtype with a new BstEII pattern which differed from type 7d by one restriction site and was designated type 7d2. Twenty-two isolates from 1968 through 1975 and from 1984 were Ad7a1. Three isolates from 1973-1974 were Ad7b. Five isolates from 1968 through 1973 were Ad7K and 27 isolates from 1992 through 1995 were Ad7d2. This demonstrates the temporal change in the circulating genome types with up to three genome types cocirculating in 1 year (1973). The two new types, Ad7k and Ad7d2 could have evolved in Israel or could have been imported by travellers and immigrants from neighboring or distant countries.

Adenovirus Infections, Human↗
PubMed1997

Identification of a new strain of fastidious enterovirus 70 as the causative agent of an outbreak of hemorrhagic conjunctivitis.

A 1994 outbreak of acute hemorrhagic conjunctivitis in Israel was caused by an enterovirus 70 strain that was distinct from previously reported strains. Characterization was by electron microscopy (eye washes), reverse transcription-PCR (RT-PCR; eyewash, specimens, eye swabs, and tears), and sequence analysis of RT-PCR-amplified fragments from the 5' noncoding region and VP1.

Amino Acid Sequence↗
PubMed1996

[Nephrotic syndrome complicating treatment with interferon alpha].

UNLABELLED: We report two cases of nephrotic syndrome with minimal glomerular change complicating alpha-interferon therapy. CASE REPORTS: The first patient was a 60-year-old man with Waldenström's disease who was given 1 million units of alpha-interferon three times a week for 22 months. Acute renal failure developed when a second protocol was started. Renal biopsy revealed intraglomerular deposits and no cellular proliferation. Total remission could not be achieved with corticosteroids. The second case was a 46-year-old man given high dose alpha-interferon (15 million units 3 times a week) for lymph node metastasis of a malignant melanoma. A nephrotic syndrome without renal failure developed during the third month of treatment. Minimal glomerular involvement was seen. Symptomatic treatment led to resolution of the nephrotic syndrome. DISCUSSION: Nine other cases of nephrotic syndrome complicating alpha-interferon therapy have been reported in the literature.

Acute Kidney Injury↗
PubMed1996

[Acute interstitial nephropathy induced by vancomycin].

The authors report a case of tubulo-interstitial nephritis with acute renal failure due to vancomycin used to treat a patient with enterococcus endocarditis. Rechallenge with vancomycin several days after stopping the drug resulted in the appearance of a maculopapular rash and rapid onset of acute oligo-anuric renal failure. Renal biopsy revealed acute interstitial nephritis. This feature is suggestive of cellular mediated hypersensitivity.

Acute Disease↗