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A column coated with a polymer inclusion film (PIF) containing Aliquat 336 as carrier cast on glass beads packed in a glass tube is described for the separation, preconcentration, and determination of zinc(II) in flow injection analysis (FIA) and continuous flow analysis (CFA) systems. In the FIA method, 200 μL of a sample solution containing 2 mol/L lithium chloride is injected into a 2 mol/L lithium chloride stream. This converts zinc(II) ion into its anionic chlorocomplexes which are then extracted into the Aliquat 336-based PIF by anion exchange. The extracted zinc(II) is then back-extracted into a stream of 1 mol/L sodium nitrate solution and determined spectrophotometrically using 4-(2-pyridylazo)resorcinol as the color reagent. The limit of detection (LOD, S/N = 2) was determined as 0.017 mg/L. The usability of the PIF-based FIA method was demonstrated by the determination of zinc in alloys. The PIF-coated column was also employed successfully in the CFA determination of zinc(II) as an impurity in commercial lithium chloride samples. For this, 2 mol/L commercial lithium chloride solution was passed through the column for a predetermined time period followed by stripping in a stream of 1 mol/L sodium nitrate solution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Using magnetoencephalography, we measured 20-Hz activity induced after the common peroneal nerve (CPN) stimulation in 15 healthy subjects during the execution of foot movement or its motor imagery, and examined whether the 20-Hz activity is suppressed during motor imagery of foot movement. The prominent 20-Hz activity was contralaterally induced in the paracentral area after CPN stimulation, and it was almost completely suppressed during execution of the foot movement and partially suppressed during its motor imagery. These results suggest that the modulation of the 20-Hz activity is a useful indicator of the motor imagery of foot movement.

Objective: To determine the effects of hypoxia and hypoxic exercise (HE) on the norepinephrine levels of various tissues in rats., Methods: Male Wistar rats were randomly assigned to 3 groups: an HE group (n = 6), a hypoxic-sedentary (HS) group (n = 6), and a normoxic-sedentary (NS) group (n = 6). The HE rats had access, ad lib, to an exercise wheel for 8 weeks. HE and HS rats were maintained in a normobaric hypoxic chamber with an FIO2 of 16%. Norepinephrine levels were measured and compared in liver, heart, diaphragm, soleus, and gastrocnemius tissues from the 3 groups., Results: Liver norepinephrine levels in the HE and HS groups were significantly lower than the levels in the NS group (P < .05). No significant difference was found in liver norepinephrine levels between the HE and the HS groups. The heart norepinephrine levels in the NS group were significantly lower than the levels in the HE (P < .01) and HS groups (P < .01). In contrast, no significant differences were found in the norepinephrine levels for the diaphragm and soleus muscle among the 3 groups. The norepinephrine levels in the gastrocnemius white muscles were significantly higher in the HS group than in the HE (P < .05) and NS groups (P < .01). P < .01 represents a significant difference at the level of 1%., Conclusions: This study demonstrated that hypoxia and HE both elicit a decreased sympathetic response in the liver tissue of male Wistar rats but cause an increased response in heart tissue. These results suggest that the sympathetic responses to long-term hypoxia and HE training are different in various rat tissues.

This study clarified the effects of long-term hypoxia and hypoxic exercise on monoamines in the whole brain, and in four specific regions of the rat brain. The male Wistar rat progenitors (P1 group) were randomly assigned to three groups: hypoxia (16.0% oxygen) and exercise (MHE-P1), hypoxia and sedentary (MHS-P1), normoxia and sedentary (MNS-P1). The male children of P1 (the first generation of hypoxic rats; F1) were randomly divided into two groups: hypoxia and exercise (MHE-F1) and hypoxic sedentary (MHS-F1). The monoamines of whole brain were measured in P1 males, and monoamines of cerebellum, frontal lobe, striatum and hippocampus were measured in F1 males. The monoamine levels of MHE-P1 were significantly lower than those of MHS-P1 and MNS-P1. No significant difference was found in monoamine levels between MHS-P1 and MNS-P1. Epinephrine, norepinephrine, and dopamine levels of the MHE-F1 group significantly decreased in the frontal lobe, cerebellum and striatum, compare with the other groups (hypoxic and sedentary; normoxic and sedentary, respectively). These monoamines in the hippocampus were not influenced by the hypoxia or hypoxic exercise conditions. This study suggests that long-term hypoxic exercise decreased monoamine levels in whole brain, and that sensitivity to hypoxia and hypoxic exercise differed according to brain region.

Early and reliable diagnosis of colorectal cancer continues to be demanding and challenging. Colorectal cancer cells express Vasoactive Intestinal Peptide (VIP) receptors in high density. We have prepared a VIP analog (TP3654), labeled it with (99m)Tc, and evaluated it in experimental animals as an agent for imaging colorectal cancer. The tissue distribution of (99m)Tc-TP3654 has been compared with that of (111)In-DTPA-Octreotide and (99m)Tc-anti-CEA scan in nude mice bearing human colorectal cancer LS174T. Finally, pharmacokinetic and tissue distribution studies of (99m)Tc-TP3654 have been performed in four normal human volunteers. Data suggest that (99m)Tc-TP3654 can be prepared efficiently without loss of its receptor specificity and biological activity. Although the 24 hr tumor uptake of (99m)Tc-TP3654 in the animal model used was modest (0.21 +/- 0.07% I.D./g), the tissue distribution profile was more favorable than that of (111)In-DTPA-Octreotide or (99m)Tc-anti-CEA scan. Human studies indicated that (99m)Tc-TP3654 had no adverse effect in any subject. Within 24 hours, approximately 70% of the injected dose cleared through the kidneys, and approximately 20% through the hepatobiliary system. In these non-fasting volunteers hepatobiliary clearance was slow and in cancer patients tumor uptake was rapid. Data suggest that (99m)Tc-TP3654 is a promising agent for imaging colorectal cancer.

Rasagiline [N-propargyl-l(R)-aminoindan] is a selective irreversible MAO-B inhibitor as is (-)deprenyl. The effect of the drug on antioxidant enzyme activities on dopaminergic tissue was examined in male F-344 rats (8.5-months-old). Two experimental groups were infused subcutaneously with rasagiline saline solutions by means of osmotic minipumps implanted subcutaneously in the back of the rats. Control animals were also similarly implanted with saline filled mini-pumps. Three-and-one-half weeks later, animals were sacrificed and selected tissue samples removed from brain, kidney and heart. Two doses of rasagiline (0.5 mg/kg/day, 1.0 mg/kg/day, both for 3.5 weeks) significantly increased catalase activities about 2-fold in substantia nigra and striatum but not in hippocampus. Interestingly, in both renal cortex and medulla. catalase (CAT) activities were significantly increased. Both Mn- and Cu,Zn-superoxide dismutase (SOD) activities were increased 2 to 4 fold in substantia nigra, striatum and renal cortex and heart. Several groups, including our own have reported an extension of survival of deprenyl-treated animals of different species. Although the mechanism(s) of the life extension by deprenyl remains unresolved, it would be interesting to investigate the effect of rasagiline on the survival of animals, since deprenyl also was shown to increase antioxidant enzyme activities in brain dopaminergic regions.

A new preparation method was devised using beta-cyclodextrin as a mobile-phase additive in a reversed-phase high-performance liquid chromatography system. Preparative separation of the biologically active (R)-enantiomer was achieved from racemic N-methylsalsolinol. Beta-cyclodextrin was removed completely in good yield by acid extraction and solid-phase extraction. By a slight modification, this method will be applicable to the isolation of various types of biologically important enantiomers.