Evaluation of hand circulation with CardioWaves photoplethysmograph device during Allen test in healthy volunteers.

OBJECTIVE: Radial artery occlusion is a potential complication of transradial procedures and its occurrence ranges from 0.8 to 30%. It is virtually always asymptomatic but the functional and sensorial consequences of a long acting hand hypoperfusion could go underestimated. CardioWaves is a novel photoplethysmograh device that allows us to detect the pulse wave amplitude of the blood flowing to the hand. Our objective was to assess in normal subjects the hand blood flow supplied by radial arteries and ulnopalmar arches, respectively, by using CardioWaves device during modified Allen's test (MAT). PATIENTS AND METHODS: MAT was performed on both hands of 60 normal subjects, age ranging 21 to 66 years, without any cardiovascular factor risk. RESULTS: Photoplethysmograh and MAT showed a high positive linear correlation (r=0.93). Despite that, MAT tends to give a higher reading by between 1.05 and 1.6 sec. 11 of 120 readings (9%) by CardioWaves showed values of radial/ulnar pulse amplitude ratio more than mean + 1 SD, suggesting a significant decrease in ulnopalmar arterial circulation when radial blood flow supply would ceased. CONCLUSIONS: The CardioWaves device allows us an accurate reading of the flow because of its independency from respiratory changes. Furthemore, the evaluation of radial and ulnar pulse wave amplitude and the ratio between them would reveal an insufficient blood flow supply by the ulnar artery irrespective of the MAT results. We suggest that their assessment before performing coronary angiography and interventions may reduce potential complication of transradial access.

Mercury pollution from irrigation with treated sewage water (TSW).

The lack of potable water in arid countries leads to the use of treated sewage water (TSW) for crop growth. Mercury accumulation (up to 500 ng/g) in agricultural soil originating from daily irrigation with TSW was found at two sites fed separately from a hospital sewage plant and an industrial plant. A control site irrigated with potable water ([Hg] <0.01 ng/ml) had much reduced levels in soil (<12 ng/g). Cold-vapour analysis of TSW revealed that Hg concentrations fluctuated widely, and were between 10-100 times higher than those of potable water. The TSW data originated from a total of 46 samples (1 L each), from both plants, collected over a 6-month period. The Hg levels varied from 0.1 to 1.0 ng/ml, which suggested that the possible source of the accumulation could be found in continuous irrigation with comparatively higher Hg levels. Remedial measures could be approached from the perspective of curbing this inconsistency to produce more consistent Hg concentrations below 0.5 ng/ml. It was found that the electrical conductivity of TSW is a useful indicator to rapidly monitor fluctuations in treatment. A novel development in the study was the potential capacity of the plastic TSW discharge-pipes to behave as crude 'chromatographic' columns for possible Hg adsorption. If this property of the pipes is developed further it could have a considerable mitigating effect on the Hg levels. Possible recommendations for remediation to limit the Hg levels and promote sustainable development are discussed.

Optimization of a high-performance liquid chromatography method to quantify bilirubin and separate it from its photoproducts: effect of column length, Ph, mobile phase composition, and flow rate.

A rapid reversed-phase (RP) high-performance liquid chromatography method for the isolation of bilirubin from its photoproducts (e.g., biliverdin) is reported. The method is based on isocratic elution using methanol:water as the mobile phase. A 24 full-factorial experimental design approach was adopted. For the optimization, the best separation was obtained using a flow rate of 1.50 mL/min, a mobile phase of 99:1 methanol:water (v/v) at pH 3.60, and a 150 x 4.6 mm id RP (C18) column containing 5-microm particles. These conditions produced the fastest total retention time of 3.38 +/- 0.055 min, and other chromatographic parameters were acceptable. Under the optimum conditions, a linear calibration curve for bilirubin was obtained over the 1.0-40.0 microg/L concentration range studied. The limit of quantification was 0.79 g/L and the limit of detection was 0.24 microg/L. Bilirubin in solution was monitored by ultraviolet detection at 450 nm.

Fluorescence enhancement of coumarin-6-sulfonyl chloride amino acid derivatives in cyclodextrin media.

Coumarin-6-sulfonyl (6-CS) amino acid derivatives form inclusion complexes with a- and /-cyclodextrins (CD) in aqueous solution. The stoichiometry of the inclusion complex and the equilibrium constant were investigated. Using a fluorescence technique and alanine-beta-CD as a model, a 1:2 guest-host complex was established, and K = 4.7 x 10(5) mol(-2) l(2) was obtained. Fluorescence enhancement was observed for all derivatives studied, with glycine exhibiting a greater enhancement, and tyrosine showing the least. The stability of the inclusion complex was found to depend on the respective sizes of the guest-host complex and their interaction.

Fluorimetric determination of D- and L-lactate derivatized with 4-(N, N-dimethylaminosulfonyl)-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ) by high-performance liquid chromatography.

A highly sensitive method, based on fluorescence derivatization with 4-N,N-dimethylaminosulfonyl-7-piperazino-2,1,3-benzoxadiazol e (DBD-PZ), was developed for the determination of D- and L-lactic acid. High-performance liquid chromatographic separation of the lactic acid derivative was achieved using an octadecylsilica column followed by enantiomeric separation on a phenylcarbamoylated beta-cyclodextrin chiral column. The separation factor for D, L-lactic acid derivatives was 1.30 using MeOH/H(2)O (80/20) as a mobile phase, and the detection limits were approximately 360 and 300 fmol on column for D- and L-lactic acid derivative, respectively. The proposed method was applied to determine D- and L-lactate in a wine and a lactic drink. Both D- and L-lactate could be determined simultaneously, with the precisions ranging from 3.50 to 5.78% for intra-day and 4.28-9.92% for inter-day determinations. The relative recovery was in the range of 91.6-100%.

Enantiomeric determination of amines by high-performance liquid chromatography using chiral fluorescent derivatization reagents.

4-(2-carboxypyrrolidin-1-yl)-7-nitro-2,1,3-benzoxadiazole (NBD-Pro), 4-(2-carboxypyrrolidin-1-yl)-7-(N,N-dimethylamino-sulphonyl)-2,1,3 - benzoxadiazole DBD-Pro), 4-(N-1-carboxyethyl-N-methyl)amino-7-nitro-2,1,3-benzoxadiazole NBD-N-Me-Ala), 4-(N-1-carboxyethyl-N-methyl) amino-7-(N,N-dimethylamino-2,1,3-benzoxadiazole. (DBD-N-Me-Ala) have been synthesized for the resolution of enantiomers of amines by high performance liquid chromatography (HPLC). The reagents react with amino group at room temperature in the presence of activation agents, 2,2'-dipyridyl disulphide (DPDS) and triphenylphosphine (TPP) to produce the corresponding diastereomers. The derivatives were detected at lambda ex = 469, lambda em = 569 for DBD-moeity and lambda ex = 469, lambda em = 535 for NBD moeity. The resulting diastereomers were efficiently resolved using reversed-phase column with aqueous acetonitrile and aqueous methanol as the mobile phase. The elution order of the derivatives were D and L when proline was used as the chiral selector but the order was reversed when the diastereomers were prepared with the reagent containing N-methyl alanine as the chiral selector. DBD-Pro and NBD-Pro seem to give better separation as compared to DBD-N-Me-Ala and NBD-N-Me-Ala.

Diagnostic problems of tuberculous cervical adenitis (scrofula).

PURPOSE: This study was designed to review the diagnostic procedure for tuberculous cervical adenitis and propose a simple protocol for the work-up of patients with suspected tuberculous cervical adenitis. Moreover, it served to increase physician awareness of tuberculosis as possible cause of cervical mass. PATIENTS AND METHODS: We performed a retrospective study of 57 patients with tuberculous cervical adenitis who were treated at North West Armed Forces Hospital, Tabuk, Saudi Arabia between March 1989 and April 1993. The results of diagnostic procedures, chest x-ray, tuberculin test, fine-needle aspiration, microbiology culture, and histopathology were reviewed. RESULTS: Forteen percent showed changes in chest x-ray, 92% had positive tuberculin test, and 50% of the culture material grew Mycobacterium tuberculosis. All specimens for histopathology were suggestive of tuberculosis. CONCLUSION: A thorough history and physical examination, tuberculin test, and fine-needle aspiration will help arrive at an early diagnosis of tuberculous cervical adenitis and allow early commencement of treatment before final diagnosis can be made by incisional biopsy and culture. Tuberculosis should be included in the differential diagnosis of neck mass.

1-(5-Dimethylamino-1-naphthalenesulphonyl)-(S)-3-aminopyrrolidine (DNS-Apy) as a fluorescence chiral labelling reagent for carboxylic acid enantiomers.

1-(5-Dimethylamino-1-naphthalenesulphonyl)-(S)-3-aminopyrrolidi ne (DNS-Apy) has been synthesized for the separation of carboxylic acid enantiomers by high-performance liquid chromatography (HPLC) and sensitive detection. The reagent reacts with carboxylic acids at room temperature in the presence of activation agents 2,2'-dipyridyl disulphide (DPDS) and triphenylphosphine (TPP). The maximum emission of the diastereomeric amide derived from (S)-phenylpropionic acid and ketoprofen derivatives of DNS-Apy was at 530 nm with excitation at 340 nm. The emission wavelength shifted towards the blue and the fluorescence intensities increased with increasing acetonitrile concentration in the medium. The diastereomers derived from anti-inflammatory drugs were efficiently resolved with a reverse-phase column using water:acetonitrile mixture as mobile phase. All of the racemate of arylpropionic acid derivatives gave equal fluorescence intensity of the two enantiomers with the exception of ketoprofen derivatives where the intensity of the first eluting enantiomer was half that of the second.

Enantiomeric Separation and Detection of 2-Arylpropionic Acids Derivatized with [(N,N-Dimethylamino)sulfonyl]benzofurazan Reagents on a Modified Cellulose Stationary Phase by High-Performance Liquid Chromatography.

(RS)-2-Arylpropionic acids (2-APAs) were derivatized with the fluorogenic reagents, 4-[(N,N-dimethylamino)sulfonyl]-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ) and 4-[[(N-hydrazinoformyl)methyl]-N-methyl]amino-7-[N,N-(dimethylamino)sulfonyl]-2,1,3-benzoxadiazole (DBD-COHz), and their enantiomeric separation by a chiral stationary phase high-performance liquid chromatography was investigated in the reversed-phase mode with H(2)O/CH(3)CN or H(2)O/MeOH as the mobile phase on a column of cellulose tris(3,5-dimethylphenyl carbamate) coated on a silica gel support (Chiralcel OD-R). The derivatives with DBD-PZ were enantiomerically separated well under the elution condition of H(2)O/MeOH, based on the π-π interaction between the derivatives and the stationary phase. The rigid and bulky structure of DBD-PZ was demonstrated to be more effective as compared to the less rigid ones. The derivatives with DBD-COHz were more efficiently separated into each enantiomer with H(2)O/CH(3)CN as the eluent. The effective separation was based on hydrogen-bonding interaction between the acid hydrazide of the derivatives and the carbamoyl moiety of the stationary phase. There was a reversal in the elution order of the enantiomers between the two fluorescent derivatives. The detection limits obtained for each enantiomer were approximately 10-30 fmol on column. The derivatization with the reagent and the concomitant use of the reversed-phase and chiral stationary-phase HPLC were demonstrated to be useful for the enantiomeric quantification in rat plasma after intravenous administration of flurbiprofen racemate, a representative of 2-APAs.