ENEA extremity dosemeter based on LiF(Mg,Cu,P) to evaluate Hp(3,alpha).

Recent epidemiological studies suggest a rather low-dose threshold (<0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimised and current dose limits for the eye lens may be reduced in the future. ICRP Publication 103 on H(p)(d), in §(136), reads that '… a depth d = 3 mm has been proposed for the rare case of monitoring the dose to the lens of the eye. In practice, however, H(p)(3) has rarely been monitored and H(p)(0.07) can be used for the same monitoring purpose… '. As recommended on the EU 'Technical recommendations for monitoring individuals occupationally exposed to external radiation', a test on the ENEA TL extremity dosemeter is herein reported. The results within the actual EU founded Optimization of RAdiation protection for MEDical staff (ORAMED) Project, whose WP2 is aimed at the quantity H(p)(3) and eye lens dosimetry in practice, are taken into account. The paper summarises the main aspects of the study carried out at ENEA-Radiation Protection Institute (Bologna, Italy) to provide practical solutions (in the use and the design) to evaluate the response of the ENEA TL extremity dosemeter in terms of H(p)(3).

Iliac artery-ureteral fistula: a fatal hemorrhage in a man with ureterocutaneostomy.

Primary and secondary artery-ureteral fistulas are a rare condition. In this case report we describe a case of misunderstood iliac artery-ureteral fistula, with negative radiological preoperative imaging, which occurred in a man as late complication of ureterocutaneostomy.

Personal dosimetry in terms of HP(3): Monte Carlo and experimental studies.

Hp(3) has been defined as the operational quantity for eye lens dosimetry. Hp(3)/ka conversion coefficients were evaluated at the GSF (Germany) in a 30x30x15 cm3 4-elements ICRU slab phantom for various energies and incident angles through Monte Carlo. The ISO report 12,794 suggests to employ a PMMA water filled phantom, of the same dimensions, for dosemeter calibration in terms of Hp(3). The present paper briefly summarises the main aspects of a study carried out at ENEA-Radiation Protection Institute (Bologna, Italy) to provide practical procedures for the calibration of dosemeters in terms of Hp(3). Tabulations of a new set conversion coefficients and air kerma backscatter factors are provided as a function of energy and incident angle. The paper demonstrates that a more accurate approach to the dosimetric assessment in terms of Hp(3) could be rather simply introduced employing a reduced phantom.

The ENEA neutron personal dosimetry service.

The ENEA Radiation Protection Institute has been operating the only neutron personal dosimetry service in Italy since the 1970s. Since the 1980s the service has been based on PADC (poly allyl diglycol carbonate) for fast neutron dosimetry, while thermal neutron dosimetry has been performed using thermoluminescence (TL) dosemeters. Since the service was started, a number of aspects have undergone evolution. The latest and most important changes are as follows: in 1998 a new PADC material was introduced in routine, since 2001 TL thermal dosimetry has been based on LiF(Mg,Cu,P) [GR-200] and (7)LiF(Mg,Cu,P) [GR-207] detectors and since 2003 a new image analysis reading system for the fast neutron dosemeters has been used. Herein an updated summary of how the service operates and performs today is presented. The approaches to calibration and traceability to estimate the quantity of H(p)(10) are mentioned. Results obtained at the performance test of dosimetric services in the EU member states and Switzerland sponsored by the European Commission and organised by Eurados in 1999 are reported. Last but not least, quality assurance (QA) procedures introduced in the routine operation to track the whole process of dose evaluation (i.e. plastic QA, acceptance test, test etching bath reproducibility and 'dummy customer' (blind test) for each issuing monitoring period) are presented and discussed.

The implementation in routine of the ENEA new personal photon dosemeter.

The ENEA photon dosemeter, introduced in 1995, consisting of two differently filtrated LiF(Mg,Cu,P) detectors, has been modified recently. The ABS (acrylonitrile butadiene styrene) plastic support has been replaced by a new aluminium card supporting the same two detectors (LiF(Mg,Cu,P) GR200). The new card, fully developed at the ENEA-Radiation Protection Institute (which is going to be patented), can now be processed through a Harshaw Model 6600 Automated TLD Reader, a hot gas reader. This paper reports the results of the individual calibration of approximately 60,000 LiF(Mg,Cu,P) GR200 detectors inserted on the new aluminium cards. Before the implementation in routine of the new cards, the reader has been characterised. Steps and tests to be made to use the card in routine (i.e. reader stability, linearity, reproducibility, etc.) are reported. The whole dosimetric system now combines the very good performances of the Harshaw Model 6600 reader and that of LiF(Mg,Cu,P) thermoluminescent material.

CR-39 acceptance test and optimisation for fast neutron dosimetry applications.

The ENEA fast neutron dosemeter is based on a planar PADC (poly allyl diglycol carbonate) placed in a polyethylene holder. The CR-39 (registered trademark of PPG Industries Inc.) material, produced by Intercast Europe S.p.A., has been used in the routine of the Individual Monitoring Service (IMS) since 1998. Since then, acceptance tests on average sheet background track density and sheet neutron sensitivity have been made on new batches as a quality control within a quality assurance programme of the IMS of ENEA-Institute for Radiation Protection (IRP). Dosemeters were irradiated with a 241Am-Be source at ENEA-IRP and processed through a chemical etching procedure (pre-etching with 40% KOH water solution 6.25 N and 60% ethyl alcohol at 70 degrees C followed by 12 h of etching in 6.25 N KOH water solution). In this paper we present the analysis of acceptance testing data for more than 30 sheets of CR-39 plastic produced in 1998, 1999 and 2000. Moreover, we compare the performance of sheets of CR-39 of standard composition with that of sheets of CR-39 with the addition of DOP (dioctylphthalate), in different concentrations, on the hasis of average background density, neutron sensitivity and background fluctuation that limit the lower detectable dose. This study demonstrates the need for acceptance tests to assure the quality of the dosimetric performance of these dosemeters, which is considerably dependent on the quality of the CR-39 plastic.

Effects of iloprost on adhesion molecules and F1 + 2 in peripheral ischemia.

BACKGROUND: Iloprost has beneficial effects on microcirculation by preventing platelet and leukocyte reciprocal activation, which is known to lead to endothelial damage and acute thrombosis. This drug also reduces inflammatory system activation by decreasing alpha M beta 2 integrin expression on the phagocyte membrane, might have a role in the protection and restoration of endothelial integrity and might interact with coagulation cascade activation. DESIGN: Forty patients were enrolled: 29 with systemic sclerosis (SSc) and 11 with peripheral artery disease (PAD). Iloprost was administered for 5 days in the first group and for 21 days in second group of patients. To ascertain whether iloprost modifies the parameters of endothelial and coagulation cascade activations, the plasma concentrations of S-ICAM-1 and F1 + 2 were detected in patients at baseline, after 5 days and, in PAD patients only, after 21 days of iloprost therapy. S-ICAM-1 is the endothelial counter receptor for alpha M beta 2 integrin and is a marker of endothelial cell activation; and F1 + 2 is a marker of coagulation cascade activation. RESULTS: After infusion of iloprost a significant decrease of S-ICAM-1 was observed in both the SSc (P < 0.002) and PAD patients (P < 0.004). Similarly, a significant decrease of F1 + 2 was observed in the SSc (P < 0.0004) and PAD patients (P < 0.003). CONCLUSIONS: The study provides evidence that iloprost reduces endothelial cells and coagulation cascade activations. Both of these mechanisms are responsible for improvement in microvascular functional capacity and for the long-term clinical benefit observed. After iloprost infusion, the SSc patients showed marked reductions in F1 + 2 and S-ICAM-1 concentrations that were statistically more significant relative to the PAD patients.

Determination of ternary mixtures of antibiotics, by ratio-spectra zero-crossing first- and third-derivative spectrophotometry.

The ratio-spectra zero-crossing first- and third-derivative spectrophotometry have been used for determining ternary mixtures of penicillin-G sodium, penicillin-G procain and dihydrostreptomycin sulphate salts. The procedures are accurate, nondestructive and do not require resolutions of equations. In both methods, calibration graphs are linear, with zero-intercept, up to 30 micrograms ml-1 of penicillin-G sodium and penicillin-G procain, and up to 42 micrograms ml-1 of dihydrostreptomycin sulphate. r = 0.9999 in each instance. Working wavelengths, 218.5, 211 and 236 nm, respectively, in the first-derivative mode, and 222.5, 311.5 and 242 nm in the third-derivative mode. Detection limits for each drug at p = 0.01 level of significance were calculated to be 0.058, 0.010 and 0.014 micrograms ml-1 and 0.14, 0.012 and 0.34 micrograms ml-1, in the first- and third-derivative methods, respectively. Both methods apply favorably to either laboratory mixtures or commercial injections.

Determination of a quaternary mixture of vitamins B6, B1, and B12 and uridine 5'-triphosphate, by derivative spectrophotometry.

A new method for determining a quaternary mixture of vitamins B6, B1, and B12 and uridine 5'-triphosphate (UPT) using second-derivative spectrophotometry is described. Calibration graphs were linear up to 30 micrograms/mL of vitamin B6 at 307 nm (r = 0.9999) and vitamin B1 at 282.7 nm (r = 0.9997) and up to 35 micrograms/mL of vitamin B12 at 360.5-374 nm, peak-to-peak (r = 0.9999), and UTP at 261 nm (r = 1.0000). Detection limits at the p = 0.05 level of significance were calculated to be 0.20, 0.46, 0.22, and 0.20 microgram/mL for vitamins B6, B1, and B12 and UTP, respectively. An exhaustive statistical analysis of the experimental data was performed to confirm the validity of the method. The procedure does not require any separation step or solving of equations. The method was successfully applied for determining synthetic mixtures and commercial injections for these drugs.

Simultaneous determination of ceftriaxone and streptomycin in mixture by 'ratio-spectra' 2nd derivative and 'zero-crossing' 3rd derivative spectrophotometry.

Binary mixtures of antibiotics, ceftriaxone sulphate and streptomycin sodium, are assayed by 'ratio-spectra' 2nd derivative and 'zero-crossing' 3rd derivative spectrophotometry. Both procedures did not require any separation step and/or solving of equations. In the first method, calibration plots are linear up to 40mug/ml of ceftriaxone at 225, 241.5, 255.5, 255.5-241.5 and 225-241.5 nm (peak-to-peak), with r ranging from 0.9999 to 1.0000, and up to 30mug/ml of streptomycin at 206 nm, r 0.9998. Detection limits, at P = 0.05 level of significance: ceftriaxone, from 0.24 to 0.47 mug/ml (at the various wavelengths), streptomycin, 0.42 mug/ml. By the second method, lines of regression are linear up to 40 mug/ml of ceftriaxone, at 227.8 and 241.7 nm (r, 0.9999 and 1.0000) and up to 35 mug/ml of streptomycin (r, 0.9999). Detection limits were calculated to be 0.35 and 0.15 mug/ml for ceftriaxone and 0.27 mug/ml for streptomycin. Both methods were successfully applied to laboratory mixtures and to mixtures of commercial injections for these drugs.

Determination of a ternary mixture of penicillin-G sodium salt, penicillin-G procain salt and dihydrostreptomycin sulphate, by third-derivative spectrophotometry.

Ternary mixtures of antibiotics, i.e. penicillin-G sodium salt, penicillin-G procain salt and dihydrostreptomycin sulphate salt, are assayed by 'zero-crossing' third-derivative spectrophotometry. Calibration plots follows Beer's law up to 40 mug/ml of penicillin-G sodium at 222.5 nm (r = 0.9997), 46 mug/ml of penicillin-G procain at 217 nm (r = 0.9999) and 36 mug/ml of dihydrostreptomycin sulphate at 211.5 nm (r = 0.9999), in the presence of one another. Detection limits at p = 0.05 level of significance were calculated to be, respectively, 0.66, 0.41 and 0.25 mug/ml. The procedure is rapid, simple, nondestructive and does not require solution of equations. The method was successfully applied for determining laboratory mixtures and commercial injections.

Simultaneous derivative spectrophotometric determination of aztreonam and L-arginine in injections.

Mixtures of aztreonam, 2S-[2 alpha,3 beta(Z)]-2-[[[1-(2-amino-4-thiazolyl-2- [(2-methyl-4-oxo-1-sulfo-3-azetidinyl) amino]-2-oxo- ethylidine]amino]oxy]-2-methyl-propanoic acid, and L-arginine are assayed by peak-to-baseline, peak-to-peak, and zero-crossing second-derivative spectrophotometry. Aztreonam is the first of a new class of beta-lactam antibiotics (i.e., the mono-bactam antibiotics, highly effective against aerobic gram-negative bacteria). Beer's law is followed for up to 31 micrograms/mL of aztreonam and L-arginine in the presence of one another. Detection limits at the p = 0.05 level of significance range from 0.11 to 0.37 micrograms/mL. The method was successfully applied to laboratory mixtures and commercial injections containing these substances.

Isokinetic strength training in below-knee amputees.

Eight below-knee amputees performed isokinetic training of knee extensor- and knee-flexor muscles for a period of 8-12 weeks at angular velocities of 60 degrees/s, 180 degrees/s and 240 degrees/s. Before and after training isokinetic and isometric knee extensor/flexor strength was measured. Muscle biopsies were taken from the vastus lateralis and the cross-sectional area of the thigh muscles was measured with computerized tomography. Peak torque of the amputated leg increased significantly in all knee-extension tests and in knee-flexion at 180 degrees/s, and in the non-amputated leg in extension at 180 degrees/s, 240 degrees/s and for isometric strength at 60 degrees knee angle. Knee-flexion strength increased at 240 degrees/s. The cross-sectional area of the muscle fibers increased in the amputated leg in all patients except one. There was no significant increase in the non-amputated leg which also was trained. The quotient between the cross-sectional areas of type II and type I fibers increased from 1.04 to 1.20 in the amputated leg, demonstrating an increase specially in the type II fibers. There was no difference in the non-amputated leg. The cross-sectional area of the thigh muscles did not show any significant change in either leg. The patients estimated their ability to walk after training to more than double the distance compared to before training. They could also manage better without walking aids. The increase in strength and the synchronous increase in the size of type II (fast twitch) fibers indicate that the training model has activated also these motor units which probably have not been given as much training earlier.

Spectrophotometric determination of paracetamol in pure form and in tablets.

A spectrophotometric method is proposed for the determination of paracetamol in pure form and in tablets. The method depends on reaction of the drug with ammonium molybdate in strongly acidic medium to produce molybdenum blue. Effects of variables such as temperature, heating time, acidity and reagent concentration have been evaluated to permit selection of the most advantageous technique. Beer's law was followed for concentrations of up to 6 micrograms ml-1 of paracetamol and the detection limit (p = 0.05) was 0.10 microgram ml-1. The molar absorptivity at 670 nm was 2.6 x 10(4) l mol-1 cm-1 and the relevant Sandell's sensitivity of the reaction was 0.0059 microgram cm-2 per 0.001 absorbance unit. Statistical analysis of the results and comparison with results by the BP method of analysis are also reported.

Second-derivative spectrophotometric assay of mixtures of dicloxacillin sodium and ampicillin sodium in pharmaceuticals.

'Zero-crossing' derivative spectrophotometry has been used for determining binary mixtures of dicloxacillin Na and ampicillin Na, which are penicillins with closely overlapping absorption spectra. The procedure is rapid, simple, nondestructive, and does not require solutions of equations. Calibration graphs are linear (r = 0.9999), with a zero intercept for up to 60 micrograms/mL of each antibiotic. Detection limits at the p = 0.05 level of significance were calculated to be 0.29 and 0.31 microgram/mL of dicloxacillin Na and ampicillin Na, respectively. The method was successfully applied to the assay of commercial injections and capsules for these drugs.

Low back pain among retired wrestlers and heavyweight lifters.

The lifetime incidence and prevalence of low back pain among 32 retired wrestlers (ages 39 to 62 years) and 13 retired heavyweight lifters (ages 40 to 61 years) were evaluated and compared to the corresponding results in a cross-sectional study of 716 men (ages 40 to 47 years). The radiologic findings and the findings upon physical examination in the athletes were compared to the findings in another study of normal, active, similarly aged men who were sampled at random. The lifetime incidence and prevalence of low back pain was higher among the wrestlers (59%) compared with both the lifters (23%) and the control group (31%). The tolerance for backache seemed to be higher among the athletes than the controls. A higher frequency of old fractures was found among the wrestlers. The athletes with fractures had a higher frequency of low back pain. A significant decrease in disk height was found among the lifters.

Zero-crossing derivative spectrophotometry for the determination of mixtures of cephaloridine and cephalothin in pure and dosage forms.

First- and second-derivative spectrophotometry, with a zero-crossing technique of measurement, has been used for the quantitation of two-component mixtures of cephaloridine and cephalothin Na, which are cephalosporins with closely overlapping spectral bands. Beer's Law is followed for up to 28 and 36 micrograms/mL of cephaloridine in the first- and second-derivative modes, respectively, and up to 36 micrograms/mL of cephalothin Na in both modes. Detection limits at the 0.05 level of significance were calculated to be 0.13 and 0.37 micrograms/mL of cephaloridine and cephalothin Na, respectively, in the first-derivative mode, and 0.25 and 0.29 micrograms/mL, respectively, in the second-derivative mode. The recovery of these antibiotics in mixtures of injectable dosage forms is also reported.

Effects of electrical muscle stimulation combined with voluntary contractions after knee ligament surgery.

The aim of the present study is to compare the effect of electrical muscle stimulation combined with voluntary muscle contractions with a program only with voluntary muscle contractions during immobilization in casts after anterior cruciate ligament surgery. Twenty-three patients, 7 women and 16 men with a mean age of 28 yr, were randomized into two groups: an experimental group (13 patients) and a control group (10 patients). Post-operatively, the patients were immobilized for 3 wk in a full leg cast with the knee flexed at an angle of 20 degrees to 30 degrees and then in a knee cast for another 3 wk. All patients had a standard program with quadriceps muscle contractions. In addition, the experimental group received electrical stimulation of the quadriceps muscle 4 X 10 min, 3 times.wk-1, at a frequency of 30 Hz. During each stimulation, the patients were requested to contract the quadriceps muscle voluntarily as well. When pre-operative measurements were compared with those at the end of the immobilization period (6 wk after the operation), a significantly larger reduction in the knee extension isometric muscle strength was found for the control group than for the experimental group. In comparisons of the data of the male subjects only, this difference was still seen to be significant. The cross-sectional area of the quadriceps muscle measured with computed tomography was significantly less reduced during the immobilization period in the experimental group than in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)