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1.
Am J Physiol Regul Integr Comp Physiol ; 326(2): R100-R109, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-37899754

RESUMEN

Cannabidiol (CBD) use has grown exponentially more popular in the last two decades, particularly among older adults (>55 yr), though very little is known about the effects of CBD use during age-associated metabolic dysfunction. In addition, synthetic analogues of CBD have generated great interest because they can offer a chemically pure product, which is free of plant-associated contaminants. To assess the effects of a synthetic analogue of CBD (H4CBD) on advanced metabolic dysfunction, a cohort of 41-wk-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats were administered 200 mg H4CBD/kg by oral gavage for 4 wk. Animals were fed ad libitum and monitored alongside vehicle-treated OLETF and Long-Evans Tokushima Otsuka (LETO) rats, the lean-strain controls. An oral glucose-tolerance test (oGTT) was performed after 4 wk of treatment. When compared with vehicle-treated, OLETF rats, H4CBD decreased body mass (BM) by 15%, which was attributed to a significant loss in abdominal fat. H4CBD reduced glucose response (AUCglucose) by 29% (P < 0.001) and insulin resistance index (IRI) by 25% (P < 0.05) compared with OLETF rats. However, H4CBD did not statically reduce fasting blood glucose or plasma insulin, despite compensatory increases in skeletal muscle native insulin receptor (IR) protein expression (54%; P < 0.05). H4CBD reduced circulating adiponectin (40%; P < 0.05) and leptin (47%; P < 0.05) and increased ghrelin (75%; P < 0.01) compared with OLETF. Taken together, a chronic, high dose of H4CBD may improve glucose response, independent of static changes in insulin signaling, and these effects are likely a benefit of the profound loss of visceral adiposity.NEW & NOTEWORTHY Cannabis product use has grown in the last two decades despite the lack of research on Cannabidiol (CBD)-mediated effects on metabolism. Here, we provide seminal data on CBD effects during age-associated metabolic dysfunction. We gave 41-wk-old OLETF rats 200 mg H4CBD/kg by mouth for 4 wk and noted a high dose of H4CBD may improve glucose response, independent of static changes in insulin signaling, and these effects are likely a benefit of loss of visceral adiposity.


Asunto(s)
Cannabidiol , Diabetes Mellitus Tipo 2 , Síndrome Metabólico , Humanos , Ratas , Animales , Anciano , Ratas Endogámicas OLETF , Síndrome Metabólico/tratamiento farmacológico , Insulina , Glucosa , Cannabidiol/farmacología , Ratas Long-Evans , Diabetes Mellitus Tipo 2/metabolismo , Glucemia/metabolismo
2.
Zootaxa ; 4975(3): 561573, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-34187030

RESUMEN

The distribution of the often dominant in density and biomass epi-endogeic and endogeic earthworm species in forests of the Northwest Caucasus was estimated based on a large array of field data and GIS modeling of modern potential areas. Quantitative accountings of earthworms were conducted annually from 2014 to 2019 in different types of forests: sticky alder forest, small-leaved forests, broadleaf forests (hornbeam and beech forests), coniferous-deciduous forests, dark coniferous forests, and pine forests (792 geographic locations). It is shown that the native species of the Caucasian fauna dominate in the number and biomass from piedmont to high mountain forests. The most widespread species that is found in all types of forests from low to high mountains and makes the main contribution to the biomass of earthworms is the Crimean-Caucasian subendemic Dendrobaena schmidti. Peregrine species of epi-endogeic and endogeic earthworms inhabit sticky alder forest, small-leaved, broadleaf and pine forests in which they inhabit together with native species, while not dominating either in numbers or in biomass among other species. Dark coniferous forests are inhabited mainly by the native endogeic species D. schmidti and A. jassyensis. Maxent modeling shows that the species of the endogeic earthworm group have wider potential areas than epi-endogeic species. The most significant bioclimatic factors that make the greatest contribution to the distribution: amount of precipitation in the driest month, altitude above the sea level, isothermality.


Asunto(s)
Bosques , Oligoquetos , Animales , Distribución Animal , Oligoquetos/clasificación , Suelo
3.
J Phys Chem Lett ; 12(4): 1284-1289, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33497232

RESUMEN

High electron affinity (EA) molecules p-type dope low ionization energy (IE) polymers, resulting in an equilibrium doping level based on the energetic driving force (IE-EA), reorganization energy, and dopant concentration. Anion exchange doping (AED) is a process whereby the dopant anion is exchanged with a stable ion from an electrolyte. We show that the AED level can be predicted using an isotherm equilibrium model. The exchange of the dopant anion (FeCl3-) for a bis(trifluoromethanesulfonamide) (TFSI-) anion in the polymers poly(3-hexylthiophene-2,5-diyl) (P3HT) and poly[3-(2,2-bithien-5-yl)-2,5-bis(2-hexyldecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione-6,5-diyl] (PDPP-2T) highlights two cases in which the process is nonspontaneous and spontaneous, respectively. For P3HT, FeCl3 provides a high doping level but an unstable counterion, so exchange results in an air stable counterion with a marginal increase in doping. For PDPP-2T, FeCl3 is a weak dopant, but the exchange of FeCl3- for TFSI- is spontaneous, so the doping level increases by >10× with AED.

4.
ChemSusChem ; 14(1): 303-305, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-32941679

RESUMEN

Biobased 5-(chloromethyl)furoate and 5-methylfuroate esters can be deprotonated to function as furylogous lithium enolates, and the former can also undergo zinc insertion to access Reformatsky-type chemistry. Carbon nucleophilicity represents hitherto little-explored reactivity in these key carbohydrate-derived platform molecules, expanding their synthetic utility and potentially opening up new sustainable product markets (e. g., in epoxy resins or biobased dyes).

5.
ACS Omega ; 4(5): 9427-9433, 2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31460033

RESUMEN

The introduction of functional groups with varying electron-donating/-withdrawing properties at the ß-position of diketopyrrolopyrrole (DPP) has been shown to affect the optoelectronic properties of the polymers. We report the synthesis of a new diketopyrrolopyrrole monomer wherein a strong electron-donating substituent, a methoxy group, was incorporated at the ß-position in an effort to modulate polymer properties. Homopolymers and co-polymers of the new ß-methoxy DPP and nonderivatized DPP were synthesized, and their properties were measured by cyclic voltammetry and UV-vis-near-infrared. Density functional theory computations also were employed to predict the degree of planarity of ß-methoxy oligomers to probe the significance of the newly introduced S-O conformational lock. The combined experimental and computational results showed a reduction in the gap between highest occupied molecular orbital/lowest unoccupied molecular orbital levels, a redshift toward the near-infrared region, and an increased planarity in the ß-methoxy polymers.

6.
J Am Chem Soc ; 138(48): 15617-15628, 2016 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-27934008

RESUMEN

Generally, the long-range electronic communication between spatially orthogonal orbitals is inefficient and limited to field and inductive effects. In this work, we provide experimental evidence that such communication can be achieved via intramolecular electron transfer between two degenerate and mutually orthogonal frontier molecular orbitals (MOs) at the transition state. Interaction between orthogonal orbitals is amplified when the energy gap between these orbitals approaches zero, or at an "orbital crossing". The crossing between two empty or two fully occupied MOs, which do not lead to stabilization, can be "activated" when one of the empty MOs is populated (i.e., electron injection) or one of the filled MOs is depopulated (i.e., hole injection). In reductive cycloaromatization reactions, such crossings define transition states with energies defined by both the in-plane and out-of-plane π-systems. Herein, we provide experimental evidence for the utility of this concept using orbital crossings in reductive C1-C5 cycloaromatization reactions of enediynes. Communication with remote substituents via orbital crossings greatly enhances regioselectivity of the ring closure step in comparison to the analogous radical cyclizations. We also present photophysical data pertaining to the efficiency of electron injection into the benzannelated enediynes.

7.
Org Lett ; 15(9): 2238-41, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23639080

RESUMEN

The para-OMe functional group, usually regarded as a conjugative p-donor, acts as an efficient hyperconjugative σ-acceptor in reductive cycloaromatization reactions. This apparent reversal of electronic properties is associated with a conformational change that aligns the σ*(O-C) orbital with the adjacent aromatic system and provides stabilization to the developing negative charge in the TS of the dianionic cyclization of enediynes. The chameleonic character of the OMe group illustrates the important role of negative hyperconjugation in anionic processes.

8.
J Org Chem ; 77(1): 75-89, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22077877

RESUMEN

Dissection of stereoelectronic effects in the transition states (TSs) for noncatalyzed azide-alkyne cycloadditions suggests two approaches to selective transition state stabilization in this reaction. First, the formation of both 1,4- and 1,5-isomers is facilitated via hyperconjugative assistance to alkyne bending and C···N bond formation provided by antiperiplanar σ-acceptors at the propargylic carbons. In addition, the 1,5-TS can be stabilized via attractive C-H···F interactions. Although the two effects cannot stabilize the same transition state for the cycloaddition to α,α-difluorocyclooctyne (DIFO), they can act in a complementary, rather than competing, fashion in acyclic alkynes where B3LYP calculations predict up to ∼1 million-fold rate increase relative to 2-butyne. This analysis of stereoelectronic effects is complemented by the distortion analysis, which provides another clear evidence of selective TS stabilization. Changes in electrostatic potential along the reaction path revealed that azide polarization may create unfavorable electrostatic interactions (i.e., for the 1,5-regioisomer formation from 1-fluoro-2-butyne and methyl azide). This observation suggests that more reactive azides can be designed via manipulation of charge distribution in the azide moiety. Combination of these effects with the other activation strategies should lead to the rational design of robust acyclic and cyclic alkyne reagents for fast and tunable "click chemistry". Further computational and experimental studies confirmed the generality of the above accelerating effects and compared them with the conjugative TS stabilization by π-acceptors.


Asunto(s)
Alquinos/química , Azidas/química , Cobre/química , Química Clic , Ciclización , Espectroscopía de Resonancia Magnética , Estructura Molecular , Estereoisomerismo
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