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Objective: Esketamine (Vesierra) is a molecule, used alone or in combination, to induce and maintain general anaesthesia and to relieve pain in emergency medicine. The aim of this study is to evaluate the long-term physicochemical stability of a 1 mg/mL solution of esketamine diluted in 0.9% sodium chloride (NaCl) and stored in polypropylene syringes at 5±3°C during 65 days (64+1 day at 22±3°C) and 72 hours at 22±3°C (room temperature), in order to centralise preparation under aseptic conditions in hospital pharmacy., Methods: Ten syringes were prepared under aseptic conditions. Five syringes were stored at 22±3°C for 3 days, and the five others were stored at 5±3°C for 64 days (+ 1 day at room temperature). The stability was periodically investigated. Particle appearance or colour changes were checked by visual inspection. A research of crystals was performed under the microscope. pH was followed to assess its stability. The turbidity of the solutions was estimated by a measure of optical densities at 350, 410 and 550 nm. The molecule concentrations were measured by ultra-high performance liquid chromatography (UHPLC) coupled with a photodiode array detection (PDA), using a newly developed method., Results: Based on microscopic examination, no crystals were observed, during the observation period. pH and absorbances at 350, 410 and 550 nm were also stable. Macroscopically, there was no change in colour and appearance of opacity, turbidity or precipitation. Statistical analysis indicates that 1 mg/mL esketamine solutions were chemically stable under these conditions, given that less than 5% of the solutions have lost more than 10% of their initial content during the study based on the prediction interval., Conclusions: One mg/mL solutions of esketamine hydrochloride are physically and chemically stable after production, for at least 72 hours at 22±3°C and 64 days at 5±3°C (+ 1 day at room temperature)., Competing Interests: Competing interests: None declared., (© European Association of Hospital Pharmacists 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

In order to avoid fluid overload, more concentrated drug solutions in intensive care units are commonly used. This study evaluated the physicochemical stability of concentrated solution of isosorbide dinitrate in polypropylene syringes during 28 days at 5°C ± 3°C with protection from light. Five syringes of 50 mL, containing 0.60 mg/mL of isosorbide dinitrate in sodium chloride 0.9% were prepared and stored at 5°C ± 3°C with protection from light during 28 days. Immediately after preparation and periodically during the storage, isosorbide dinitrate concentration was measured by an ultra-performance liquid chromatography. Spectrophotometric absorbance at different wavelengths, pH measurements, and microscopic observations were also performed. All solutions were physicochemically stable during the whole period storage at 5°C ± 3°C. No color change, turbidity, precipitation or opacity, significant pH variations, or optic densities were observed in the solutions. Any crystals were seen by microscopic analysis. The concentration of isosorbide dinitrate remained above 90% of the initial concentration during the 28 days of storage. Solutions of isosorbide dinitrate 0.60 mg/mL in syringe of sodium chloride 0.9 % injection can be considered physically and chemically stable for 28 days when stored in syringes at 5°C ± 3°C with protection from light and may be prepared in advance by a centralized intravenous additive service., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

In some emergency clinical situations, the injection of a more concentrated drug solution in the intensive care units is common. The purpose of this study was to evaluate the physicochemical stability of concentrated solutions of amiodarone hydrochloride in polypropylene syringes during 28 days of storage at 5°C ± 3°C, with protection from light. Five syringes of 50 mL, containing 25 mg/mL of amiodarone in dextrose 5%, were prepared and stored at 5°C ± 3°C with protection from light during 28 days. Immediately after preparation and periodically during the storage, amiodarone hydrochloride concentrations were measured by ultra-performance liquid chromatography. Spectrophotometric absorbance at different wavelengths, pH measurement, and microscopic observations were also performed. All solutions were physicochemically stable during the study period when stored at 5°C ± 3°C. No color change, turbidity, precipitation, opacity, significant pH variations, or optic densities were observed in the solutions. No crystals were seen by microscopic analysis. The concentration of amiodarone did not decrease during the 28 days of storage. Solutions of amiodarone 25 mg/mL in syringes of dextrose 5% are physically and chemically stable for at least 28 days when stored in syringes at 5°C ± 3°C with protection from light and may be prepared in advanced by a centralized intravenous additive service., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

Intensive care units use drug solutions within higher concentrations to avoid fluid overload. The purpose of this study was to evaluate the physicochemical stability of concentrated solutions of noradrenaline bitartrate in polypropylene syringes during 30 days of storage at 5°C ± 3°C. Five 50-mL syringes containing 0.240 mg/mL of noradrenaline bitartrate in 0.9% sodium chloride were prepared and stored at 5°C ± 3°C during 30 days. Immediately after preparation and periodically during the storage, noradrenaline concentrations were measured by high-performance liquid chromatography. Spectrophotometric absorbance at different wavelengths, pH measurement, and microscopic observations were also performed. The results showed that all solutions were physicochemically stable during the entire storage period at 5°C ± 3°C, and no color change, turbidity, precipitation, opacity, significant pH variations, nor optic densities were observed. Microscopic analysis was used to determine if there was any formation of crystals. The concentration of noradrenaline was not found to decrease during the 30 days of storage. Solutions of noradrenaline bitartrate 0.240 mg/mL in syringes of 0.9% sodium chloride were physically and chemically stable for at least 30 days when stored in syringes at 5°C ± 3°C and may be prepared in advanced by a centralized intravenous additive service., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

The objectives of this study were to determine if the preparation of vancomycin hydrochloride in advance of infusion could improve the quality of the drug, time management of drug delivery, cost savings of drug delivery, and to investigate the long-term stability of vancomycin hydrochloride (brand name Vancocin®) infusion in glucose 5% polyolefin bags versus the generic (Vancomycine®) at 5°C ± 3°C. Five bags of each infusion 1 g/100 mL vancomycin hydrochloride in 5% glucose (Vancocin ® and Vancomycine®) were stored up to 57 days at 5°C ± 3°C. A visual inspection and pH measurement were performed periodically during the storage, and the concentrations were measured by high-performance liquid chromatography-diode array detection. No color change or precipitation in the solution was observed throughout the study period. As recommended by the U.S. Food and Drug Administration, the lower confidence limit at 95% of the concentration for the solutions remained superior to 90% of the initial concentration up to 43 days for the brand vancomycin (Vancocin®) infusion (96% ± 2%) and up to 57 days for the generic (Vancomycine®) (95% ± 4%). The solutions prepared either from brand or generic vancomycin hydrochloride were chemically stable more than one month (43 days for the brand and 57 days for the generic solution) and could be prepared in advance in a centralized intravenous additive service facility., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

Vancomycin hydrochloride is often used for antibiotherapy in oral solution for hospitalized patients. Preparation of this solution in advance could improve time management or cost savings of drug delivery. Brand and generic products of vancomycin hydrochloride are now commercially available. The aim of this study was to investigate the long-term stability of the vancomycin hydrochloride brand name Vancocin versus the generic Vancomycine at 5°C ± 3°C. Five vials of each oral solution of 1.25 g/100 mL Vancocin and Vancomycine were stored up to 57 days at 5°C ± 3°C. Concentrations were measured by high-performance liquid chromatography-diode array detection. Visual inspection by microscopy and spectrophotometry, as well as pH measurement, were performed periodically during the storage period. No color change or precipitation in the solution was observed throughout the study period. The lower confidence limit of the concentration for these solutions remained superior to 90% of the initial concentration as recommended by the U.S. Food and Drug Administration up to a 57-day storage period for Vancocin (106.47%) and vancomycin (102.73%). The solutions prepared either from brand or generic vancomycin hydrochloride were chemically stable for more than one month and could be prepared in advance., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

To improve quality assurance, security, time management, and cost saving of drug delivery, preparation in advance of intravenous solutions has been developed for several infusion solutions. The objective of this study was to investigate the stability of esomeprazole 0.4 mg/mL and 0.8 mg/mL in 5% dextrose polyolefin bags after freezing, long-term storage, and microwave thawing. The stability of five polyolefin bags containing approximately 0.4 mg/mL of esomeprazole and five other bags containing approximately 0.8 mg/mL in 5% dextrose prepared under aseptic conditions was studied after freezing for 1 month at -20 degrees C, thawing in a microwave oven with a validated cycle, and stored at 5 degrees C +/- 3 degrees C. Esomeprazole concentration was measured by high-pressure liquid chromatography using a reversed-phase column C8, a mobile phase consisting of 35% of acetonitrile and 65% of Na2HPO4 buffer at pH 7.59 with HPO4 (2 M) and NaOH (0.5 M), and detection with a diode array detector at 280 nm. Visual, microscopic, and spectrophotometric observation and pH measurements were also performed. No precipitation occurred in the preparations but little change of color was observed. No microaggregate was observed with optical microscopy or revealed by a change of absorbance at 350, 410, and 550 nm. Based on a shelf life of 90% residual potency, esomeprazole solutions (0.4 and 0.8 mg/mL) were stable for at least 20 or 29 days, respectively, after a freezing and microwave thawing period, where 95% one-side lower confidence limit of the concentration-time profile remained superior to 90% of the initial concentration. During this period, the pH values of drug solutions have been observed to decrease without affecting chromatographic parameters. Within these limits, esomeprazole (0.4 and 0.8 mg/mL) in 5% dextrose infusions may be prepared and frozen in advance by a centralized intravenous admixture service, thawed, and stored at least 20 days at 5 degrees C +/- 3 degrees C before use in clinical units.

The objective of this study was to investigate the stability of cocaine hydrochloride 50 mg/mL (5%) aqueous solution stored in glass bottles at 5°C ± 3°C or at room temperature. Ten bottles of cocaine hydrochloride 50 mg/mL were prepared under aseptic conditions. Five were stored at 5°C ± 3°C and five at room temperature. pH measurements, optic density measurements at different wave-lengths, and optic microscopic observations were performed periodically during the storage. A forced-degradation test with hydrochloric acid 12M and NaOH 5M with and without heating at 100°C was also performed. The concentrations were measured by high-pressure liquid chromatography with photodiode-array detection. Stability of the solutions was defined as the period for which the one-sided 95% confidence interval of the common regression line remains superior to 90% of the initial concentration as recommended by the U.S. Food and Drug Administration. The forced-degradation tests did not influence the chromatographic peaks of the studied component. No significant change of optic density was seen and no crystals were observed with the optic microscope during the study. The solutions stored at 5°C ± 3°C or at room temperature maintained 90% of their concentration after 24 days. During this period, the pH of the solution decreased from 5.39 to 4.34 at 5°C ± 3°C and from 5.37 to 3.44 at room temperature. In order to alleviate adverse reactions to the eye with too low pH, we propose a period of validity of 15 days at 5°C ± 3°C and 48 hours at room temperature. During this period, the degradation of the preparation was lower than 10%, and the values of pH were higher than 4.0.

Background/objectives: The impact of an elevation of cardiac biomarkers occurring after percutaneous coronary intervention (PCI) on long-term outcome remains controversial. Most available data are based on observational registries using multivariable analysis. In this study, a case-control approach was used to assess separately the impact of post-PCI elevation of CK-MB on the short-term in-hospital outcome and on the long-term outcome after hospital discharge., Methods: Between 1 January 1996 and 31 December 2008, a postprocedural rise of CK-MB was observed in 363 among 8346 consecutive PCI procedures (4·3%). The overall in-hospital mortality for patients with or without CK-MB elevation after PCI was 8·5% and 1·5%, respectively (P < 0·001). For 245 hospital survivors with CK-MB elevation, we found 245 control cases matched for 9 relevant clinical parameters in our PCI database during the same period. The long-term survival of these patients was assessed by KM estimates., Results: Despite an increased in-hospital mortality among patients with periprocedural elevation of CK-MB, the long-term outcome of patients who are discharged alive is independent of CK-MB release, curves of overall survival and of survival free of recurrence of myocardial infarction being similar up to 10 years after hospital discharge., Conclusions: In our population, the elevation of CK-MB after PCI identified a high-risk subgroup for in-hospital mortality but had no impact on the long-term prognosis, once the patient is discharged alive from the hospital., (© 2014 Stichting European Society for Clinical Investigation Journal Foundation.)

Tobacco smoking is widespread and is one of the world's most prevalent modifiable risk factors for morbidity and mortality. It is important to facilitate smoking cessation better in order to reduce the health consequences of tobacco use. The most effective approach assisting smokers in their quit attempts combines both pharmacotherapy and nonpharmacological interventions. This review summarizes the latest international epidemiological data available on tobacco use, considers the associated effects on health, and reviews existing policies against tobacco use. Among the interventions for smoking cessation, the three major pharmacotherapies (which have demonstrated efficacy when combined with behavioral support) are discussed: nicotine replacement therapy (NRT), bupropion, and varenicline. As the newest pharmacotherapy made available in this area, particular consideration is given to varenicline, and a review of our clinical experience is offered.

Background: High levels of release of inflammatory markers after coronary angioplasty are predictors of late restenosis. Sirolimus-eluting stent reduces the risk of restenosis., Aim of the Study: To compare the release of inflammatory markers after coronary angioplasty with sirolimus-eluting stent and bare metal stent., Methods: Sixteen patients with a proximal left anterior descending coronery artery stenosis were randomly assigned to receive either bare metal stent (n = 8) or sirolimus-eluting stent (n = 8). We measured simultaneously aortic and coronary sinus concentrations of the von Willebrand factor antigen, tumor necrosis factor-alpha and interleukin-6 before, immediately and after 2 h after stenting. High-sensitivity C-reactive protein and troponin-I circulating levels were measured before and 6 and 24 h after coronary angioplasty., Results: Before stenting, all values were similar in both groups. The coronary sinus change of the von Willebrand factor antigen level between baseline and 2 h after stenting was + 20.1 +/- 26.9% in the bare metal stent group and -5.7 +/- 23.02% in the sirolimus-eluting stent group (P < 0.05). We observed a significant increase in the von Willebrand factor antigen (from 132.8+/-58.8 to 169 +/- 40.7%, P < 0.05) systemic concentrations 24 h after stenting in the bare metal stent group but not in the sirolimus-eluting stent group (from 140.6+/-84% to 136 +/- 39.5%), P = NS)., Conclusion: The present study shows that a difference in the release of inflammatory markers can be detected after coronary stenting with bare metal stent or sirolimus-eluting stent. The lower release of the von Willebrand factor antigen in the coronary sinus 2 h after the procedure and the lower systemic concentrations of the von Willebrand factor antigen 24 h after stenting in the sirolimus-eluting stent group are likely to reflect a reduced production of the von Willebrand factor antigen at the site of the vascular injury.

Background: Ketorolac tromethamine is a nonsteroidal agent with potent analgesic and moderate antiinflammatory activity. Advance preparation of intravenous solution could be useful to improve quality assurance, time management, and cost-savings of drug delivery., Objective: To investigate the effect of freezing, long-term storage, and microwave thawing on the stability of ketorolac tromethamine in dextrose 5% infusion., Methods: Five polyolefin bags of solution containing ketorolac tromethamine 20 mg per 100 mL of dextrose 5% were frozen for 3 months at -20 degrees C, thawed in a microwave oven with a validated cycle, and stored at 4 degrees C. The concentration of ketorolac was measured by HPLC. Visual inspection and pH measurement were also carried out., Results: No color change or precipitation was observed. Ketorolac was stable for at least 60 days under refrigeration after freeze-thaw. Throughout this period, the lower confidence limit of the estimated regression line of the concentration-time profile remained >90% of the initial concentration, and the pH value decreased slightly without affecting chromatographic parameters., Conclusions: Within these limits, ketorolac tromethamine in dextrose 5% infusion may be prepared and frozen in advance by a centralized intravenous admixture service, then thawed before use in clinical units.

Background: Intravenous cefuroxime sodium solution could be prepared in advance by a centralized hospital pharmacy service to improve safety and time management., Objective: To investigate the effect of freezing and microwave thawing on the solution stability of cefuroxime., Methods: Cefuroxime 1.5 g in 100 mL of dextrose 5% in polyolefin bags was frozen individually (group A) or in one package (group B) for 98 days at -20 degrees C. The solutions were then thawed using microwaves at 270 (light cycle) or 800 watts (hard cycle) and stored at 4 degrees C. The cefuroxime concentration was measured by HPLC. Visual inspection was performed and pH was measured at that time. Stability of the solution was defined as a concentration remaining superior to 90% of the initial concentration by regression analysis., Results: No color change or precipitation in the solutions was observed. In group A, stability was at least 23 and 21 days after light and hard cycle thawing, respectively. In group B, stability was at least 21 and 18 days, respectively, with the pH increasing without affecting chromatographic parameters., Conclusions: The optimal conditions for advance preparation of a solution containing cefuroxime 1.5% in dextrose 5% may be freezing of individual containers followed by a light cycle of microwave thawing.

Background: Sufentanil is a powerful central anesthetic and analgesic of the opiate family that can be used with levobupivacaine for epidural administration. Advance preparation of intravenous solution could be useful to improve quality, time management, and cost-savings of drug delivery., Objective: To investigate how freezing, long-term storage, and microwave thawing can affect the stability of sufentanil citrate and levobupivacaine HCl in NaCl 0.9% (saline) (w/v) polyvinyl chloride (PVC) bags., Methods: The stability of 5 bags of solution containing sufentanil 500 microg and levobupivacaine 625 mg per 500 mL of saline solution in PVC bags was studied after freezing for 4 months at -30 degrees C, thawing in a microwave oven with a validated cycle, and storage at 4 degrees C. The concentrations of the drugs were measured by HPLC using a reversed-phase column, a mobile phase consisting of 18% acetonitrile (v/v) in tertabutyl ammonium hydrogen sulfate buffer 0.03 M pH 3.00 +/- 0.05, and UV detection at 235 nm for sufentanil and 260 nm for levobupivacaine. Visual inspection and pH measurement were also performed., Results: No color change or precipitation was observed. Sufentanil and levobupivacaine were stable for at least 70 days at 4 degrees C after freezing and thawing. Throughout this period, the 95% lower confidence limit of the concentration-time profile remained >90% of the initial concentration. During this period, the pH value remained stable., Conclusions: Within the limits defined here, a mixture of sufentanil citrate and levobupivacaine HCl may be prepared in advance and kept frozen.

Tramadol hydrochloride (Contramal) is often used as infusions for hospitalized patients to manage or prevent acute or chronic pain that requires analgesia at opioid level. Advance preparation of intravenous solutions of tramadol hydrochloride could be useful to improve quality assurance, time management and cost savings of drug delivery; but little is known about their stability after freezing followed by microwave thawing. The purpose of this study was to investigate how freezing, long-term storage and microwave thawing can affect the stability of tramadol in 5% dextrose infusion. The stability of five polyvinyl chloride bags of solution containing 100mg of tramadol/100mL of 5% dextrose was studied after the solution was frozen for 4 months at -20 deg C, followed by thawing in a microwave oven with a validated cycle and final storage at 4 deg C. Concentration of tramadol was measured by high-performance liquid chromatography using a reversed-phase column, a mobile phase consisting of 30% acetonitrile in phosphate bufer pH 2.5 and ultraviolet detecion at 230 nm. Visual inspection and pH measurement were also performed. No color change or precipitation was observed. Tramadol was stable for at least 60 days. Throughout this period, the lower confidence limit of the estimated regression line of the concentration-time profile remained at above 90% of the initial concentration. During this stability period, the pH value decreased slightly without affecting chromatographic parameters. Within these limits, tramadol in 5% dextrose infusion may be prepared frozen in advance by a centralized intravenous admixture service, then thawed before use in clinicl units.

Cefepime is often used in antibiotic infusions for the hospitalized patients. Using intravenous solutions of cefepime prepared in advance can be efficient, but little information is available about the stability of that antibiotic after freezing followed by microwave thawing. The purpose of this study was to investigate how freezing, long-term storage, and microwave thawing can affect the stability of cefepime in 5% dextrose injection. The stability of 5 polyvinyl chloride bags of solution containing 2g of cefepime per 100 mL of 5% dextrose injection was studied after the bags had remained frozen for 1 month at -20 deg C, were thawed in a microwave oven with a validated cycle, and were stored at 4 deg C. The concentration of cefepime was measured by high-performance liquid chromatography by means of a reversed phase column, a mobile phase consisting of 10% acetonitrile and pentane sulfate buffer, and ultraviolet detection at 254 nm with a diode array detecor. Visual inspection was also conducted, and pH measurements were obtained. No color change or precipitation in the solution was observed. Cefepime remained stable for 11 days. During this period, the 95% lower confidence limit of the estimated regression line of the concentration-time profile remained above 90% of the initial concentration and the pH value increased slightly without affecting chromatographic parameters. Within those limits, cefepime may be prepared in advance by a centralized intravenous admixture service; it may be frozen and then thawed in a microwave before use in clinical units.

The advance preparation of intravenous solutions of teicoplanin, which is often used in antibiotic infusions for hospitalized patients, may be advantageous. The objective of this study was to investigate the stability of teicoplanin stored at 4 deg C in polyvinyl chloride bags to determine whether such solutions could be safely stored without deterioration. Five bags containing 0.4g teicoplanin per 100 mL of 5 % dextrose injection were studied for 1 month by means of high-performance liquid chromatography, visual inspection, and pH measurement. The color of teicoplanin diluted in dextrose became slightly yellow, and the pH values of the preparations decreased significantly during the period of the study without affecting the chromatographic parameters. The teicoplanin solution was stable for 6 days at 4 deg C as a result of the shortest shelf life of 90% residual potency of the five major glycopeptide components. Despite the color and pH variations, the teicoplanin infusion remained chemically stable when stored up to 6 days at 4 deg C in polyvinyl chloride bags. Thus the infusion could be prepared in advance by a centralized intravenous admixture service for use within the limits described.

Urinary cotinine was measured according to its inhibitory activity on the agglutination of cotinine-coated latex particles by anti-cotinine antibodies, the agglutination being measured by optical counting of the remaining non-agglutinated particles (particle counting, PaC). The detection limit was 0.03 microgram/ml and the practical range extended from 0.03 to 3.9 micrograms/ml. The correlation results of 320 urine samples with those of high pressure liquid chromatography, enzyme-linked (Coti-Tracq EIA, Serex Inc., Maywood, NJ, USA), and fluorescence polarization immunoassay (TDX instrument, Abbott, Abbott Park, IL, USA) were r = 0.90, r = 0.69, r = 0.87, respectively, whereas the correlation coefficients between the assays other than particle counting ranged from 0.62 to 0.88. PaC does not require any separation step and can thus be easily automated.

The relationships between tobacco smoking and both alcohol and drug consumption were investigated in 2 431 healthy individuals aged 18-29 y. We used a questionnaire to evaluate smoking habits and alcohol and drug intake, and these parameters (i.e., cotinine-to-creatinine concentration ratio, amphetamines, cannabinoids, opiates, and cocaine) were quantified via urine analyses. Urinary cotinine concentration was significantly higher in current smokers (mean +/- standard deviation: 717 +/- 61 ng/mg creatinine, n = 881) than in non- or exsmokers (32 +/- 16 ng/mg creatinine, n = 1550). Information gleaned from the questionnaires revealed that there was a greater proportion of current smokers among consumers of alcohol than among nonconsumers. Significantly (p < .001) more current smokers than non- or exsmokers self-reported that they consumed sedatives, stimulants, or illegal drugs. Urinary cotinine concentrations were highest in consumers of alcohol and in self-reported consumers of sedatives (p < .0001), stimulants (p = .01), and illegal drugs (p < .0001). We found higher urinary cotinine concentrations in subjects who had positive urinary amphetamines, cannabinoids, or opiates. Even though the prevalence of alcohol and drug consumption remained low in the population we studied, such behaviors were clearly related to tobacco smoking.

Background and Objective: Vancomycin is often used in antibiotic infusions for hospitalized patients and it is advantageous to prepare such intravenous solutions in advance. The objective of this study was to investigate the long-term stability of this antibiotic stored at 4 degrees C in polyvinyl chloride (PVC) bags., Method: Five bags each of 0.5 or 1 g vancomycin hydrochloride per 100 ml of 5% dextrose were studied for 2 months by high-performance liquid chromatography, visual inspection and pH measurement., Results: No colour change or precipitation was observed. The pH values of the preparations increased significantly over the period of study without influencing the antibiotic concentration. Based on a shelf-life of 90% residual potency, the vancomycin solutions were stable for at least 58 days at 4 degrees C., Conclusion: From a chemical stability viewpoint, the antibiotic may be prepared in advance by a centralized intravenous admixture service for use within the limits described.

An assay for anti-toxoplasma IgG antibodies based on agglutination of latex particles was set up and compared with commercial immunoassays. The reaction was measured by instrumental counting of particles remaining unagglutinated. The running time was 45 min. This test (PaC) was compared using 243 serum samples with four automated commercial immunoassays: the Enzymum test Toxo IgG (ES300, Boehringer), the Vidas Toxo IgG (Biomérieux), the IMX Toxo IgG (Abbott), the Magia Toxoplasma gondii IgG (Merck). The mean values (+/- SD) obtained by IMX (25 IU +/- 68) and ES300 (45 IU +/- 142) were significantly lower than the values obtained by Vidas (73 IU +/- 237, p < 10(-4) and p = 0.006, respectively), by Magia (80 IU +/- 300, p < 10(-4) and p = 0.0005) and by PaC (70 IU +/- 260, p < 10(-4) and p = 0.0126). The correlations between PaC and Toxo IgG Boehringer, Biomérieux, Abbott, Merck were r = 0.97, r = 0.98, r = 0.94, r = 0.98, respectively. The correlation coefficients between the enzyme-immunoassays ranged from 0.96 to 0.99. All positive samples by PaC were found to be positive by enzyme-immunoassays except for eight sera which were doubtful positives by the Enzymum test ToxoIgG from Boehringer. No negative sample by PaC was found positive by any of the enzyme-immunoassays. In PaC, when two latex preparations coated with different antigen were compared, the correlation was rather weak (r = 0.93) suggesting that the selection of the antigen can be critical. In conclusion, the four automated commercial immunoassays now available gave similar results. However, the discrepancies observed in this study underlined the importance of clinical and biological follow-up of the patients and the necessity to confirm the result. The introduction of a new technique such as PaC, which is now available for a large variety of assays in Clinical Chemistry and Microbiology, is justified by its intrinsic advantage of homogeneity. Therefore, automation is easy as well as the control of possible interference.

Small amounts of urinary proteins observed at early stages of diabetic nephropathy may result from both glomerular and proximal tubular dysfunction. However, the relative contribution of the two mechanisms remains controversial. We compared the urinary excretion of three low-molecular-weight proteins (albumin, alpha 1-microglobulin and retinal-binding protein) in 104 diabetic patients and 104 control subjects who had a plasma creatinine concentration of less than 130 mumol/l. Excretion of low-molecular-weight proteins was expressed as the ratio of protein to creatinine concentration. There were significant correlation (p < 0.01) between excretion of the three low-molecular-weight proteins measured in urine sample and 24-h urine collections in diabetic and control subjects. The concentrations of these proteins in single voided urinary samples and 24-h urine collections in diabetic patients were highly correlated. Excretion of retinal-binding protein, alpha 1-microglobulin and glucose in 24-h urine collections and of RBP and glucose in urinary samples was higher in diabetic than non-diabetic patients regardless of the type of diabetes and insulin-dependence. alpha 1-microglobulin and albumin excretions in urinary samples were significantly influenced by blood glucose control, as attested by the glycosylated haemoglobin level. Increased urinary excretion of alpha 1-microglobulin and retinol-binding protein reflected proximal tubular dysfunction in diabetic patients. However, only alpha 1-microglobulin correlated with the glycaemic control. It remains to be determined whether this protein could serve as an additional early marker of diabetic nephropathy.

Cefazolin and cefuroxime sodium are often used as antibiotic infusions for hospitalized patients. Because advance preparation of these intravenous solutions is efficient, the stability of both antibiotics stored at 4 degrees C in polyvinyl chloride (PVC) bags was studied. Five bags of solutions containing either 1 g of cefazolin sodium or 1.5 g of cefuroxime sodium per 100 ml of 5% dextrose were studied for 1 month by high-performance liquid chromatography (HPLC), visual inspection and pH measurement. No colour change or precipitation was observed. The pH values of both drugs increased significantly over the period of study. Based on a shelf-life of 90% residual potency, the cefuroxime sodium concentration was stable for 13 days when stored at 4 degrees C, and the cefazolin sodium concentration was stable for at least 30 days at 4 degrees C. Within these limits, both antibiotics may be prepared in advance by a centralized intravenous admixture service.

The relationship between psychotechnic and education levels and smoking habits was evaluated in a population of 2,430 Belgian male army conscripts who were 18-29 y of age. Smoking habits were quantified by a questionnaire and by urinary cotinine-to-creatinine concentration ratio. The results were analyzed relative to education level (graded 1-4) and to results of psychotechnic tests (scored 1-9). The urinary cotinine-to-creatinine concentration ratio was correlated strongly with the number of cigarettes smoked/d (r = .76, p < .00005). The concentrations averaged 27 +/- 153 ng/mg (mean +/- standard deviation) creatinine in nonsmokers, 69 +/- 186 ng/mg creatinine in exsmokers, and 388 +/- 392 and 867 +/- 833 ng/mg creatinine in subjects who smoked fewer than or more than 10 cigarettes/d, respectively. Significant inverse relationships were observed between the urinary cotinine-to-creatinine concentration ratio and both education (p < .0001) and psychotechnic levels (p < .0001). The inverse relationship between smoking and both the education and psychotechnic levels underlined the importance of adapting smoking prevention programs to the intellectual capacities of the populations targeted.

An assay of immunoglobulin M (IgM) antitoxoplasma antibodies which is rapid (less than 30 min), homogeneous, and reliable (interassay coefficient of variation, less than 11%) is proposed. Its principle is based on the observation that a suspension of latex particles coated with toxoplasma antigens, after treatment with proteinase K, becomes less agglutinable by IgG antibodies but more agglutinable by IgM antibodies. The difference between the activities of the two classes of antibodies is increased by the addition of a monoclonal antibody directed against the Fc region of IgM. Agglutination is measured with a special instrument which optically counts the particles that remain free after the reaction. Turbidimetric reading, although less sensitive, is also suitable. No significant interferences either by IgG antitoxoplasma antibodies or by rheumatoid factor or antinuclear antibodies were observed. The sensitivity was similar to that of the immunosorbent agglutination assay.

An assay of anti-HBs antibodies based on agglutination of latex particles coated with recombinant HBs-antigen was compared with Abbott radioimmunoassay (Abbott-RIA), which uses a human plasma-derived antigen. The population examined consisted of 76 Abbott-RIA anti-HBs-negative prevaccinated subjects and 1044 serum samples anti-HBs found positive by Abbott-RIA, including 283 samples of subjects vaccinated either with a human plasma-derived vaccine (group A; n = 180) or with a recombinant vaccine (group B; n = 103). Correlation coefficients between the two techniques were respectively r = 0.89 for the whole population (n = 1044), r = 0.98 in group A and r = 0.74 in group B. Anti-HBs titres were higher with latex than with RIA in group B as shown by the regression slopes: latex = 508 + 1.11 RIA in group A and latex = -1138 + 3.97 RIA in group B, suggesting that some vaccinated subjects from group B produced antibodies against epitopes proper to the recombinant antigen. In the prevaccinated population and in group A, the latex results were compared with those of radioimmunoassays (Abbott, Sorin) and enzyme immunoassays (Behring, Roche, Pasteur). Only the Roche-EIA detected anti-HBs in the prevaccinated subjects. The correlation between the various immunoassays was r greater than 0.96 only for values higher than 100 IU/l.

Particle counting immunoassay is based on latex agglutination, the reaction being measured by instrument counting of the particles remaining unagglutinated. Most interference which generally affects latex agglutination can be avoided by pepsin digestion of the sample, provided the antigen (Ag) of interest resists pepsin, which is the case of the hepatitis B surface antigen (HBsAg). Pepsin treatment has the additional advantage of inactivating antibodies and so releasing the Ag from immune complexes. We have set up an assay of HBsAg, proceeding in a prototype of Impact Instrument (Acade Diagnostic Systems, Belgium) at a rate of 60 samples.h-1 and a total running time of 2 or 4 h. This assay was compared with Abbott radioimmunoassay (RIA) in 706 consecutive patients (A) and 31 selected sera for which values close to the cut-off had been obtained by RIA (B). In A, 38 sera were found positive and 668 negative by both methods. In B, RIA after neutralization classified the samples as positive (n = 14), negative (n = 14), or dubious (n = 3). Complete agreement between latex and RIA was achieved for nine positive, 12 negative, and two dubious samples. Of five RIA-positive samples, two were classified as latex-negative and three as dubious in the latex assay. One sample dubious in RIA was found latex-positive and two RIA-negative samples were found, respectively, latex-positive and dubious; when retested after pepsin digestion, the first of them became RIA-positive.(ABSTRACT TRUNCATED AT 250 WORDS)