Heavy metals in Egyptian spices and medicinal plants and the effect of processing on their levels.

To determine the contamination of Egyptian spices and medicinal plants with heavy metals, a total of 303 samples, which represent 20 different types of spices and medicinal plants that were collected from areas of exportation in Egypt, were analyzed for heavy metals. Some of them have different growing seasons, and each has its own agricultural practices and several shipments. The results revealed that heavy metal contents in spice and medicinal plants depend on the plant species. The maximum levels of heavy metals in the analyzed samples were 14.4, 2.44, 33.75, 2.85, 0.10, 68.80, 343.0, 11.40, and 1046.25 microg/g for Pb, Cd, Cr, Ni, Sn, Zn, Mn, Cu, and Fe, respectively. Cobalt was not detected in any of the various samples under investigation. The levels of heavy metals determined in the analyzed samples were found to exceed the maximum allowable levels of Zentrale Erfassungs und Bewertungsstelle für Umweltchemikalien. The investigated medicinal plants were also processed by two different methods to determine the behavior of their metal contents during processing. It has been found that boiling the plant in water leads to the extraction of higher amounts of the metal from the plant than immersing it in the hot water. The achieved results were tabulated.

Double-blind, randomized, multicenter study of doxacurium vs. pancuronium in intensive care unit patients who require neuromuscular-blocking agents.

OBJECTIVE: To compare the neuromuscular-blocking and hemodynamic effects of doxacurium vs. pancuronium administered by intermittent bolus to intensive care unit (ICU) patients who required neuromuscular block to facilitate mechanical ventilation for > or = 24 hrs. DESIGN: A multicenter, prospective, double-blind, randomized study comparing doxacurium, a new benzylisoquinolone neuromuscular-blocking agent, with pancuronium. SETTING: ICUs of three tertiary care hospitals. PATIENTS: Forty critically ill patients (29 male, 11 female) with an average age of 52.5 yrs (range 19 to 80). INTERVENTIONS: With approval of our Institutional Review Boards and after obtaining informed consent, 40 critically ill patients were entered into the study. Histories and the results of physical examinations were recorded, laboratory data were collected, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were calculated during the 8 hrs before the start of the study medication. Patients received either doxacurium (initial dose of 0.04 mg/kg) or pancuronium (initial dose of 0.07 mg/kg) by bolus injection with continuous measurement of vital signs every minute for 15 mins. We measured the degree of neuromuscular blockade using a peripheral-nerve stimulator to measure the Train-of-Four count. Patients were rebolused (doxacurium dose of 0.025 mg/kg, pancuronium dose of 0.05 mg/kg) based on clinical criteria, which were substantiated by measurement of the Train-of-Four count. The neuromuscular-blocking drugs were stopped when the patient no longer required paralysis or after 5 days of therapy, whichever came first. Group comparisons were made using repeated measures analysis of variance, Fisher's exact test, and two sample t-tests, when appropriate. Spearman's rank-correction coefficients were calculated to assess the relationship of onset time and recovery time with all baseline laboratory values and the APACHE II scores. A p < .05 was used to establish statistical significance. MEASUREMENTS AND MAIN RESULTS: There were no differences between the two groups with respect to age, gender, or APACHE II scores. There were no differences between groups in terms of adverse experiences, nor with respect to time of onset of block, number of doses, or the duration of neuromuscular blockade (2.6 vs. 2.2 days for doxacurium vs. pancuronium, respectively). There was a statistically significant increase in heart rate after the initial dose of pancuronium (120 +/- 23 vs. 109 +/- 22 beats/min postinjection vs. preinjection, respectively; p < .05) without any differences noted after doxacurium (107 +/- 21 vs. 109 +/- 21 beats/min, respectively). Furthermore, once neuromuscular block was discontinued, the pancuronium group had a more prolonged and variable recovery time (279 +/- 229 mins) compared with the doxacurium group (138 +/- 46 mins, p < .05). CONCLUSIONS: In critically ill patients requiring neuromuscular block for > 24 hrs, doxacurium was well tolerated without evidence of tachycardia and with a relatively prompt recovery profile.

Regulation of tetrahydrobiopterin biosynthesis in cultured adrenal cortical tumor cells by adrenocorticotropin and adenosine 3',5'-cyclic monophosphate.

Y-1 adrenal cortical tumor cells in culture, which contain substantial amounts of tetrahydrobiopterin [6R-(L-erythro-1',2'-dihydroxypropyl)5,6,7,8-tetrahydropterin] (BH4) and GTP cyclohydrolase (GTP-CH), were used to study the regulation of BH4 biosynthesis by ACTH and cAMP. ACTH produced a dose-dependent increase in steroidogenesis, BH4 levels and GTP-CH activity. Maximal stimulation of BH4 biosynthesis occurred at the same concentration of ACTH that caused maximal stimulation of steroidogenesis. ACTH-(1-24) was more potent than ACTH-(1-39). The stimulation of BH4 biosynthesis by ACTH was dependent on cell density, being greater at lower cell densities, but was independent of time in culture. The lack of stimulation by ACTH at higher cell densities was due to an increase in the specific activity of GTP-CH in the control cells as density increased. This increase may be due in part to the increased release of steroids, since exogenous steroids added to low density cultures also resulted in an increase in the specific activity of the enzyme. Addition of steroids had no effect on ACTH-dependent stimulation of BH4 biosynthesis at low cell densities. (Bu)2cAMP, 8-bromo-cAMP, and forskolin all produced time- and dose-dependent increases in BH4 levels, GTP-CH activity, and steroidogenesis. Maximum increases in GTP-CH and BH4 occurred at concentrations similar to those required for maximal stimulation of steroidogenesis. In the Kin-8 mutant of Y-1 cells, which has a type 1 cAMP-dependent protein kinase with an altered regulatory subunit, ACTH was unable to increase BH4 levels or GTP-CH activity at a concentration that produced maximal stimulation of BH4 and steroid biosynthesis in the parent Y-1 line. These studies indicate that Y-1 cells in culture are useful for studying the regulation of BH4 biosynthesis in the adrenal cortex.