Ceftriaxone ameliorates motor deficits and protects dopaminergic neurons in 6-hydroxydopamine-lesioned rats

Parkinson's disease is caused by the degeneration of dopaminergic neurons in substantia nigra. There is no current promising treatment for neuroprotection of dopaminergic neurons. Ceftriaxone is a beta-lactam antibiotic and has been reported to offer neuroprotective effects (Rothstein, J.-D., Patel, S., Regan, M.-R., Haenggeli, C., Huang, Y.-H., Bergles, D.-E., Jin, L., Dykes, H.-M., Vidensky, S., Chung, D.-S., Toan, S.-V., Bruijn, L.-I., Su, Z.-Z., Gupta, P., and Fisher, P.-B. (2005) Beta-lactam antibiotics offer neuroprotection by increasing glutamate transporter expression Nature433, 73-77). In the present study, efficacy of ceftriaxone in neuroprotection of dopaminergic neurons and amelioration of motor deficits in a rat model of Parkinson's disease were investigated. Ceftriaxone was administrated in 6-hydroxydopamine-lesioned rats. Using behavioral tests, grip strength and numbers of apomorphine-induced contralateral rotation were declined in the ceftriaxone-treated group. More importantly, cell death of dopaminergic neurons was found to decrease. In addition, both the protein expression and immunoreactivity for GLT-1 were up-regulated. The present results strongly indicate that ceftriaxone is a potential agent in the treatment of Parkinson's disease.link_to_OA_fulltex

Phosphato, chromato, and perrhenato complexes of titanium(IV) and zirconium(IV) containing Klaui's tripodal ligand

Treatment of titanyl sulfate in dilute sulfuric acid with 1 equiv of NaLOEt (L-OEt(-) = [(eta(5) -C5H5)Co{P(O)(OEt)(2)}(3)](-)) in the presence of Na3PO4 and Na4P2O7 led to isolation of [(LOEtTi)(3)(mu-O)(3)(mu(3)-PO4)] (1) and [(LOEtTi)(2)(mu-O)(mu-P2O7)1 (2), respectively. The structure of 1 consists of a Ti3O3 core capped by mu(3)-phosphato group. In 2, the [P2O7](4-) ligands binds to the two Ti's in a U:172,171 fashion. Treatment of titanyl sulfate in dilute sulfuric acid with NaLOEt and 1.5 equiv of Na2Cr2O7 gave [(LOEtTi)(2)(mu-CrO4)(3)] (3) that contains two LOEtTi3+ fragments bridged by three mu-CrO42--O,O' ligands. Complex 3 can act as a 6-electron oxidant and oxidize benzyl alcohol to give ca. 3 equiv of benzaldehyde. Treatment of [LOEtTi(OTf)(3)] (OTf- = triflate) with [n-Bu4N][ReO4] afforded [{LOEtTi(ReO4)(2)}(2)(mu-O)] (4). Treatment of [LOEtMF3] (M = Ti and Zr) with 3 equiv of [ReO3(OSiMe3)] afforded [LOEtTi(ReO4)(3)] (5) and [LOEtZr(ReO4)(3)(H2O)] (6), respectively. Treatment of [LOEtMF3] with 2 equiv of [ReO3(OSiMe3)] afforded [LOEtTi(ReO4)(2) (ReO4)(2)F] (7) and [{LOEtZr(ReO4)(2)}(2)(mu-F)(2)] (8), respectively, which reacted with Me3SiOTf to give [LOEtM(ReO4)(2)(OTf)] (M = Ti (9), Zr (10)). Hydrolysis of [LOEtZr(OTf)(3)] (11) with Na(2)WO(4)center dot xH(2)O and wet CH2Cl2 afforded the hydroxo-bridged complexes [{LOEtZr(H2O)}(3)(mu-OH)(3)(mu(3)-O)][OTf](4) (12) and [{LOEtZr(H2O)(2)}(2)(mu-OH)(2)][OTf](4) (13), respectively. The solid-state structures of 1-3, 6, and 11-13 have been established by X-ray crystallography. The LOEtTiIv complexes can catalyze oxidation of methyl p-tolyl sulfide with tert-butyl hydroperoxide. The bimetallic TV Re complexes 5 and 9 were found to be more active catalysts for the sulfide oxidation than other Ti(IV) complexes presumably because Re alkylperoxo species are involved as the reactive intermediates

Half-Sandwich Titanium(IV) Complexes with Klaui's Tripod Ligand

Treatment of [Ti(O-i-Pr)2Cl2] with NaLOEt (LOEt- = [CpCo{P(O)(OEt)2}3]-, Cp = η5-C5H5) afforded [LOEtTi(O-i-Pr)2Cl] that reacted with HCl in ether to give [LOEtTiCl3] (1). The average Ti−O and Ti−Cl distances in 1 are 1.975 and 2.293 Å, respectively. Reaction of titanyl sulfate with NaLOEt in water followed by addition of HBF4 afforded [LOEtTiF3] (2), the Ti−O and Ti−F distances of which are 2.020(2) and 1.792(2) Å, respectively. The Zr(IV) analogue [LOEtZrF3] (3) was prepared similarly from zirconyl nitrate, NaLOet, and HBF4 in water. The Zr−O and average Zr−F distances in 3 are 2.139(2) and 1.938(2) Å, respectively. Treatment of 1 with tetrachlorocatechol (H2Cl4cat) afforded [LOEtTi(Cl4cat)Cl] (4). The average Ti−O(P), Ti−O(C), and Ti−Cl distances in 4 are 1.972, 1.926, and 2.334 Å, respectively. Hydrolysis of 4 in the presence of Et3N yielded the μ-oxo dimer [(LOEt)2Ti2(Cl4cat)2(μ-O)] (5). The average Ti−O(P), Ti−O(C), and Ti−O(Ti) distances in 5 are 2.027, 1.926, and 1.7977(9) Å. Treatment of 1 with 1,1‘-binaphthol (BINOLH2) in the presence of Et3N afforded [(LOEt)2Ti2(μ-O)2(μ-BINOL)]·2BINOLH2 (6·2BINOLH2). Complex 1 is capable of catalyzing ring opening of epoxides with Me3SiN3 under solvent-free conditions presumably via a Ti−azide intermediate

Relationships between physical and social behavioural changes and the mental status of homebound residents in hong kong during the covid-19 pandemic

202101 bcrcVersion of RecordPublishe

Titanium(IV) and zirconium(IV) sulfato complexes containing the Klaui tripodal ligand: Molecular models of sulfated metal oxide surfaces

Treatment of titanyl sulfate in about 60 mM sulfuric acid with NaLOEt (L-OEt(-) = [(eta(5)-C5H5)Co{P(O)(OEt)(2)}(3)](-)) afforded the mu-sulfato complex [(LOEtTi)(2)(mu-O)(2)(mu-SO4)] (2). In more concentrated sulfuric acid (>1 M), the same reaction yielded the di-mu-sulfato complex [(LOEtTi)(2)(mu-O)(mu- SO4)(2)] (3). Reaction of 2 with HOTf (OTf=triflate, CF3SO3) gave the tris(triflato) complex [LOEtTi(OTf)(3)] (4), whereas treatment of 2 with Ag(OTf) in CH2Cl2 afforded the sulfato-capped trinuclear complex [{(L-OEt)(3)Ti-3(mu- O)(3)}(mu(3)-SO4){Ag(OTf)}][OTf] (5), in which the Ag(OTf) moiety binds to a mu-oxo group in the T-3(mu-O)(3) core. Reaction of 2 in H2O with Ba(NO3)(2) afforded the tetranuclear complex (L-OEt)(4)Ti-4(mu-O)(6) (6). Treatment of 2 with [{Rh(cod)Cl}(2)] (cod = 1,5-cyclooctadiene), [Re(CO)(5)Cl], and [Ru(tBu(2)bpy)(PPh3)(2)Cl-2] (tBu(2)bpy=4,4'-di-tertbutyl-2,2'-dipyridyl) in the presence of Ag(OTf) afforded the heterometallic complexes [(L-OEt)(2)Ti-2(O)(2)(SO4) {Rh(cod)}(2)][OTf](2) (7), [(L-OEt)(2)Ti(O)(2)- (SO4){Re(CO)(3)}][OTf] (8), and [{(L-OEt)(2)Ti-2(mu-O)} mu(3) - SO4) (mu-O)(2){Ru(PPh3)(tBu(2)bpy)}][OTf](2) (9), respectively. Complex 9 is paramagnetic with a measured magnetic moment of about 2.4 mu(B). Treatment of zirconyl nitrate with NaLOEt in 3.5 M sulfuric acid afforded [(L-OEt)(2)Zr(NO3)][LOEtZr(SO4) (NO3)] (10). Reaction of ZrCl4 in 1.8 M sulfuric acid with NaLOEt in the presence Na2SO4 gave the R-sulfato-bridged complex [LOEtZr(SO4)(H2O)](2)(mu-SO4) (11). Treatment of 11 with triflic acid afforded [(LOEt)(2)Zr][OTf](2) (12), whereas reaction of 11 with Ag(OTf) afforded a mixture of 12 and trinuclear [{LOEtZr(SO4)(H2O)}(3)(mu-SO4)][OTf] (13). The Zr-IV triflato complex [LOEtZr(OTf)(3)] (14) was prepared by reaction of LOEtZrF3 with Me3SiOTf. Complexes 4 and 14 can catalyze the Diels-Alder reaction of 1,3-cyclohexadiene with acrolein in good selectivity. Complexes 2-5, 9-11, and 13 have been characterized by X-ray crystallography