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Copper-67 (T 1/2  = 61.83 h, E β- mean =141 keV, I β- total =100%; E γ  = 184.577 keV, I γ  = 48.7%) is a promising radionuclide for theranostic applications especially in radio immunotherapy. However, one of the main drawbacks for its application is related to its limited availability. Various nuclear reaction routes investigated in the last years can result in 67 Cu production, although the use of proton beams is the method of choice taken into account in this work. The goal of this work is a revision of the cross-sections aimed at 67 Cu yield, which were evaluated for the 68 Zn(p,2p) 67 Cu reaction route up to 80 MeV proton energy. A well-defined statistical procedure, i.e., the Simultaneous Evaluation on KALMAN (SOK), combined with the least-squares concept, was used to obtain the evaluated data together with the covariance matrix. The obtained evaluated data were also compared to predictions provided by the nuclear reaction model codes TALYS and EMPIRE, and a partial agreement among them has been found. These data may be useful for both existing and potential applications in nuclear medicine, to achieve an improvement and validation of the various nuclear reaction models, and may also find applications in other fields (e.g., activation analysis and thin layer activation)., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Disulfiram (DSF), used for the treatment of alcohol use disorders (AUDs) for over six decades, most recently has shown promise for treating cocaine dependence. Although DSF's mechanism of action in alcohol abuse is due to the inhibition of liver mitochondrial aldehyde dehydrogenase (ALDH2), its mechanism of action in the treatment of cocaine dependence is unknown. DSF is a pro-drug, forming a number of metabolites each with discrete pharmacological actions. One metabolite formed during DSF bioactivation is S-(N, N-diethylcarbamoyl) glutathione (carbamathione) (carb). We previously showed that carb affects glutamate binding. In the present studies, we employed microdialysis techniques to investigate the effect of carb administration on dopamine (DA), GABA, and glutamate (Glu) in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC), two brain regions implicated in substance abuse dependence. The effect of DSF on DA, GABA, and Glu in the NAc also was determined. Both studies were carried out in male rats. Carb (20, 50, 200 mg/kg i v) in a dose-dependent manner increased DA, decreased GABA, and had a biphasic effect on Glu, first increasing and then decreasing Glu in both the NAc and mPFC. These changes all occurred concurrently. After carb administration, NAc and mPFC carb, as well as carb in plasma, were rapidly eliminated with a half-life for each approximately 4 min, while the changes in DA, GABA, and GLu in the NAc and mPFC persisted for approximately two hours. The maximal increase in carb (Cmax) in the NAc and mPFC after carb administration was dose-dependent, as was the area under the curve (AUC). DSF (200 mg/kg i p) also increased DA, decreased GABA, and had a biphasic effect on Glu in the NAc similar to that observed in the NAc after carb administration. When the cytochrome P450 inhibitor N-benzylimidazole (NBI) (20 mg/kg i p) was administered before DSF dosing, no carb could be detected in the NAc and plasma and also no changes in NAc DA, GABA, and GLu occurred. Changes in these neurotransmitters occurred only if carb was formed from DSF. When NBI was administered prior to dosing with carb, the increase in DA, decrease in GABA, and biphasic effect on GLu was similar to that seen after dosing with carb only. The i p or i v administration of carb showed similar changes in DA, GABA, and GLu, except the time to reach Cmax for DA as well as the changes in GABA, and GLu after i p administration occurred later. The elimination half-life of carb and the area under the curve (AUC) were similar after both routes of administration. It is concluded that carb must be formed from DSF before any changes in DA, GABA, and GLu in the NAc and mPFC are observed. DSF and carb, when administered to rats, co-release DA, GABA, and GLu. Carb, once formed can cross the blood brain barrier and enter the brain. Although inhibition of liver ALDH2 is the accepted mechanism for DSF's action in treating AUDs, the concurrent changes in DA, GABA, and GLu in the NAc and mPFC after DSF administration suggest that changes in these neurotransmitters as a potential mechanism of action not only for AUDs, but also for cocaine dependence cannot be excluded., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The thermal neutron-induced activation cross section for the (186)W(n,gamma)(187)W reaction was measured at 0.0536eV neutron energy using TRIGA Mark-II research reactor, Atomic Energy Research Establishment, Savar, Dhaka, Bangladesh. The (197)Au(n,gamma)(198)Au monitor reaction induced in a high-purity gold foil was used to determine the effective neutron beam intensity. The activities induced in sample and monitor foils were measured nondestructively by a high-resolution HPGe gamma-ray detector. The present experimental cross-section value is the first one at 0.0536eV. The obtained new cross section that amounts to 26.6+/-1.6b is 2% higher than the recently reported data in ENDF/B-VII and 5% lower than that of JENDL-3.3.

11 beta,18-Epoxy-2 alpha,3 alpha,18,21-tetrahydroxy-5 alpha,17 alpha- pregnan-20-one (2 alpha-hydroxy-3 alpha,5 alpha-tetrahydro-17-isoaldosterone) and its apo isomer have been identified by high-field NMR studies, supported by thermospray HPLC/MS, to be among the major polar metabolites formed from incubation of aldosterone with rat liver microsomal fraction. Indications that unreduced 2 alpha-hydroxy-aldosterone is also present among the metabolites have still to be confirmed.

Subcellular fractionation of male rat kidney revealed that the nuclear and plasma membrane fractions isolated from the 1,000 g pellet retained a significant proportion of the aldosterone ring-A reducing activity. Improved HPLC solvent systems separated all six possible ring-A reduced metabolites of aldosterone and revealed that 80-90% of the reduced metabolites synthesized by purified nuclei and plasma membranes were 5 alpha-reduced compounds consisting of 5 alpha-DHA and 3 alpha,5 alpha-THA in ratios of 1:2 (nuclei) and 1:1 (membranes). The 105,000 g cytosol also synthesized significant quantities of reduced, hydroxylated, and conjugated metabolites of aldosterone. In contrast, the majority of the reduced metabolites of aldosterone synthesized by kidney cytosol were 5 beta-products, consisting principally of 5 beta-DHA and smaller quantities of 3 alpha,5 beta-THA and 3 beta,5 beta-THA. The synthesis of reduced aldosterone metabolites in the cytosol, nuclear, and plasma membrane fraction was inhibited by both 5 and 50 microM concentrations of the antimineralocorticoids, progesterone, K+-canrenoate, and corticosterone. Progesterone was the strongest inhibitor of the synthesis of 5 alpha-DHA and 3 alpha,5 alpha-THA in both nuclei and plasma membranes. The overall order of inhibition of the synthesis of ring-A reduced metabolites in the kidney subcellular fractions was progesterone greater than K+-canrenoate greater than corticosterone; both progesterone and K+-canrenoate inhibited 5 alpha-reduction more than 5 beta-reduction.

[3H]Aldosterone is transformed into several metabolites by subcellular fractions of rat kidney. 80-90% of the metabolites synthesized by nuclei and plasma membranes are 5 alpha-DHAldo and 3 alpha,5 alpha-THAldo in ratios of 1:2 and 1:1 respectively; small quantities of 3 beta,5 alpha-THAldo are also synthesized. In contrast, kidney cytosol metabolizes Aldo principally to 5 beta-reduced products with co-chromatograph with 5 beta-DHAldo and 3 alpha,5 beta-THAldo. Several polar neutral metabolites, as well as sulfate and acidic metabolites are also synthesized by the cytosol fraction. Similar 5 alpha-reduced metabolites, 5 alpha-DHAldo, 3 alpha,5 alpha-THAldo and 3 beta,5 alpha-THAldo are also synthesized when [3H]aldosterone is incubated in vitro with toad urinary bladder for 1 and 5 h. Significant quantities of 5 beta- and 20 beta-reduced products and sulfate and acidic metabolites are also synthesized. The metabolism of [3H]aldosterone in both target tissues is significantly inhibited by aldosterone antagonists. Several of the reduced metabolites of aldosterone synthesized in kidney and toad bladder possess significant mineralocorticoid activity. 5 alpha-DHAldo and 3 alpha,5 alpha-THAldo possess 1/10 and 1/30 and 3 alpha,5 beta possesses 1/80-1/100 of the antinatriuretic activity of Aldo. It is suggested that the metabolism of Aldo in its target tissues may be linked to regulation or expression of the hormone's actions.