Osteochondroma of the pubic symphysis causing hematuria: a case report and literature review.

BACKGROUND: Osteochondroma is the most common benign bone neoplasm and is sometimes referred to as osteocartilaginous exostosis. The symptoms caused by osteochondroma are rare, especially the urogenital complications. Therefore, this tumour is sometimes misdiagnosed. CASE PRESENTATION: This report described a 70-year-old woman with hematuria who was initially misdiagnosed with a bladder tumour in the outpatient department by a urologist. However, during cystoscopy, we found that the mass did not resemble a bladder tumor. Multidisciplinary approach with careful analysis of the imaging data suggested the diagnosis of osteochondroma. Open surgical excision of the mass was done and histology confirmed the diagnosis of benign osteochondroma. After 6 months of follow-up, the patient was still asymptomatic. CONCLUSIONS: This case illustrates that hematuria is caused by not only urogenital disease but also osteochondroma. We present this case to draw the attention of clinicians to osteochondroma of the pubic symphysis.

Nickel-Iron Dithiolato Hydrides Derived from H2 Activation by Their µ-Hydroxo Ligand-Containing Analogues.

Here, we describe the synthesis and characterization of the two µ-hydrido models of [NiFe]H2ases prepared from a new type of H2 activation by the corresponding two µ-hydroxo models. In addition, another µ-hydrido model prepared by the anionic exchange between one of the two µ-hydrido models and KPF6 is also reported. Interestingly, the synthesis of the two µ-hydrido models from H2 activation represents the first functional modeling of the H2 activation catalyzed by the [NiFe]H2ase (Ni-SIr)I state to give the Ni-R state.

Studies on Chemical Reactivity and Electrocatalysis of Two Acylmethyl(hydroxymethyl)pyridine Ligand-Containing [Fe]-Hydrogenase Models (2-COCH2-6-HOCH2C5H3N)Fe(CO)2L (L = η1-SCOMe, η1-2-SC5H4N).

On the basis of preparation and characterization of [Fe]-H2ase models (2-COCH2-6-HOCH2C5H3N)Fe(CO)2L (A, L = η1-SCOMe; B, L = η1-2-SC5H4N), the chemical reactivities of A and B with various electrophilic and nucleophilic reagents have been investigated, systematically. Thus, when A reacted with 1 equiv of MeCOCl in the presence of Et3N in MeCN to give the η2-SCOMe-coordinated acylation product (2-COCH2-6-MeCO2CH2C5H3N)Fe(CO)2(η2-SCOMe) (1), treatment of A with excess HBF4·Et2O in MeCN gave the cationic MeCN-coordinated complex [(2-COCH2-6-HOCH2C5H3N)Fe(CO)2(MeCN)](BF4) (2). In addition, when 2 was treated with 1 equiv of 2,6-(p-4-MeC6H4)2C6H3SK or PPh3 in CH2Cl2 to give the thiophenolato- and PPh3-substituted derivatives (2-COCH2-6-HOCH2C5H3N)Fe(CO)2[2,6-(p-MeC6H4)2C6H3S] (3) and [(2-COCH2-6-HOCH2C5H3N)Fe(CO)2(PPh3)](BF4) (4), treatment of B with 1 equiv of PMe3 or P(OMe)3 in THF afforded the phosphine- and phosphite-substituted complexes (2-COCH2-6-HOCH2C5H3N)(η1-2-SC5H4N)Fe(CO)2L (5, L = PMe3; 6, L = P(OMe)3). Interestingly, in contrast to A, when B reacted with excess HBF4·Et2O in MeCN to afford the BF3 adduct [2-COCH2-6-HO(BF3)CH2C5H3N]Fe(CO)2(η1-2-SC5H4N) (7), reaction of B with 1 equiv of p-MeC6H4COCl in the presence of Et3N in MeCN gave not only the expected 2-acylmethyl-6-p-toluoyloxomethylpyridine-containing complex (2-COCH2-6-p-MeC6H4CO2CH2C5H3N)Fe(CO)2(η2-2-SC5H4N) (8), but also gave the unexpected 2-toluoyloxovinyl-6-toluoyloxomethylpyridine-containing complex (2-p-MeC6H4CO2C2H-6-p-MeC6H4CO2CH2C5H3N)Fe(CO)2(η2-2-SC5H4N) (9). While the possible pathways for the novel reactions leading to complexes 1, 2, and 7-9 are suggested, the structures of complexes B, 1-4, and 6-9 were unambiguously confirmed by X-ray crystallography. In addition, model complexes A and B have been found to be catalysts for proton reduction to H2 from TFA under CV conditions.

Hydrophilic Quaternary Ammonium-Group-Containing [FeFe]-Hydrogenase Models: Synthesis, Structures, and Electrocatalytic Hydrogen Production.

The first quaternary ammonium-group-containing [FeFe]-hydrogenase models [(µ-PDT)Fe2 (CO)4 {κ2 -(Ph2 P)2 N(CH2 )2 NMe2 BzBr}] (2; PDT=propanedithiolate) and [(µ-PDT)Fe2 (CO)4 {µ-(Ph2 P)2 N(CH2 )2 NMe2 BzBr}] (4) have been prepared by the quaternization of their precursors [(µ-PDT)Fe2 (CO)4 {κ2 -(Ph2 P)2 N(CH2 )2 NMe2 }] (1) and [(µ-PDT)Fe2 (CO)4 {µ-(Ph2 P)2 N(CH2 )2 NMe2 }] (3) with benzyl bromide in high yields. Although new complexes 1-4 have been fully characterized by spectroscopic and X-ray crystallographic studies, the chelated complexes 1 and 2 converted into their bridged isomers 3 and 4 at higher temperatures, thus demonstrating that these bridged isomers are thermodynamically favorable. An electrochemical study on hydrophilic models 2 and 4 in MeCN and MeCN/H2 O as solvents indicates that the reduction potentials are shifted to less-negative potentials as the water content increases. This outcome implies that both 2 and 4 are more easily reduced in the mixed MeCN/H2 O solvent than in MeCN. In addition, hydrophilic models 2 and 4 act as electrocatalysts and achieve higher icat /ip values and turnover numbers (TONs) in MeCN/H2 O as a solvent than in MeCN for the production of hydrogen from the weak acid HOAc.

Synthetic and Structural Studies of 2-Acylmethyl-6-R-Difunctionalized Pyridine Ligand-Containing Iron Complexes Related to [Fe]-Hydrogenase.

As active site models of [Fe]-hydrogenase, tridentate 2-acylmethyl-6-methoxymethoxy-difunctionalized pyridine-containing complexes η(3)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(L1) (4, L1 = I; 5, SCN; 6, PhCS2) were prepared via the following multistep reactions: (i) etherification of 2-MeO2C-6-HOC5H3N with ClCH2OMe to give 2-MeO2C-6-MeOCH2OC5H3N (1), (ii) reduction of 1 with NaBH4 to give 2-HOCH2-6-MeOCH2OC5H3N (2), (iii) esterification of 2 with 4-toluenesulfonyl chloride to give 2-TsOCH2-6-MeOCH2OC5H3N (3), (iv) nucleophilic substitution of 3 with Na2Fe(CO)4 followed by treatment of the resulting Fe(0) intermediate Na[(2-CH2-6-MeOCH2OC5H3N)Fe(CO)4] (M1) with I2 to give complex 4, and (v) condensation of 4 with KSCN and PhCS2K to give complexes 5 and 6, respectively. In contrast to the preparation of complexes 4-6, bidentate 2-acylmethyl-6-methoxymethoxy-difunctionalized pyridine-containing model complexes η(2)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(I)(L2) (7, L2 = PPh3; 8, Cy-C6H11NC) and η(2)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(L3) (9, L3 = 2-SC5H4N; 10, 8-SC9H6N) were prepared by ligand exchange reactions of 4 with PPh3, Cy-C6H11NC, 2-KSC5H4N, and 8-KSC9H6N, respectively. Particularly interesting is that the tridentate 2,6-bis(acylmethyl)pyridine- and 2-acylmethyl-6-arylthiomethylpyridine-containing model complexes η(3)-[2,6-(COCH2)2C5H3N]Fe(CO)2(L4) (11, L4 = PPh3; 12, CO) and η(3)-2-(COCH2-6-ArSCH2C5H3N)Fe(CO)2(ArS) (13, ArS = PhS; 14, 2-S-5-MeC4H2O) were obtained, unexpectedly, when 2,6-(TsOCH2)2C5H3N reacted with Na2Fe(CO)4 followed by treatment of the resulting mixture with ligands PPh3 and CO or disulfides (PhS)2 and (2-S-5-MeC4H2O)2. Reactions of ligand precursors 3 and 2,6-(TsOCH2)2C5H3N with Na2Fe(CO)4 were monitored by in situ IR spectroscopy, and the possible pathways for producing complexes 4 and 11-14 via intermediates Na[(2-CH2-6-MeOCH2OC5H3N)Fe(CO)4] (M1), Na[(2-CH2-6-TsOCH2C5H3N)Fe(CO)4] (M2), and (2-COCH2-6-CH2C5H3N)Fe(CO)3 (M3) are suggested. New compounds 1-14 were characterized by elemental analysis, spectroscopy, and, for some of them, X-ray crystallography.

Synthesis, structural characterization, and electrochemical properties of dinuclear Ni/Mn model complexes for the active site of [NiFe]-hydrogenases.

Four new dinuclear Ni/Mn model complexes RN(PPh2)2Ni(µ-SEt)2(µ-Cl)Mn(CO)3 (7, R = p-MeC6H4CH2; 8, R = EtO2CCH2) and RN(PPh2)2Ni(µ-SEt)2(µ-Br)Mn(CO)3 (9, R = p-MeC6H4CH2; 10, R = EtO2CCH2) have been prepared via the four separated step-reactions involving six new precursors RN(PPh2)2 (1, R = p-MeC6H4CH2; 2, R = EtO2CCH2), RN(PPh2)2NiCl2 (3, R = p-MeC6H4CH2; 4, R = EtO2CCH2), and RN(PPh2)2Ni(SEt)2 (5, R = p-MeC6H4CH2; 6, R = EtO2CCH2). The Et3N-assisted aminolysis of Ph2PCl with p-MeC6H4CH2NH2 or EtO2CCH2NH2·HCl in CH2Cl2 gave the azadiphosphine ligands 1 and 2 in 38% and 53% yields, whereas the coordination reaction of 1 or 2 with NiCl2·6H2O in CH2Cl2/MeOH afforded the mononuclear Ni dichloride complexes 3 and 4 in 59% and 78% yields, respectively. While thiolysis of 3 or 4 with EtSH under the assistance of Et3N in CH2Cl2 produced the mononuclear Ni dithiolate complexes 5 and 6 in 64% and 68% yields, further treatment of 5 and 6 with Mn(CO)5Cl or Mn(CO)5Br resulted in formation of the dinuclear Ni/Mn model complexes 7-10 in 31-73% yields. All the new compounds 1-10 have been structurally characterized, while model complexes 7 and 9 have been found to be catalysts for HOAc proton reduction to hydrogen under CV conditions.

Structural and functional biomimetics of [Fe]-hydrogenase featuring a mono-, di- or tetrasubstituted pyridine ligand with a fac-C, N, and S ligation.

The combined structural and functional modeling study of [Fe]-H2ase has remained a great challenge, to date. Now, we report a series of new structural and functional [Fe]-H2ase models (1-6) that contain a mono-, di- or tetrasubstituted pyridine ligand with a biomimetic fac-C, N, and S ligation. While models 1-3, 5 and 6 are conveniently prepared by a novel flexible pyridine ligand (FPL)-based method, model 4 is prepared simply by an intramolecular CO replacement reaction of model 3. More interestingly, the structural study by spectroscopy and X-ray crystallography proves that these new models include a biomimetic fac-acyl (or methylene) C, pyridyl N, and thioether S ligation to an Fe(II) center and the C-Fe(II) σ bond is trans to an iodo ligand. In addition, the chemical reactivity study proves that they all have the enzyme-like H2 activation and hydride transfer functions in the presence of imidazolium Im+, AgBF4 and Et3N. Particularly interesting is that a possible pathway for such H2 activation and hydride transfer reactions catalyzed by a representative model 4 is proposed and the existence of the highly unstable 5-coordinate intermediate M4 and Fe-H species M5 is supported by the isolation and characterization of their MeCN-coordinated derivative 7 and chloro-substituted derivative 8, respectively.

Functionalized nickel(II)-iron(II) dithiolates as biomimetic models of [NiFe]-H2ases.

To develop the structural and functional modeling chemistry of [NiFe]-H2ases, a series of new biomimetics for the active site of [NiFe]-H2ases have been prepared by various synthetic methods. Treatment of the mononuclear Ni complex (pnp)NiCl2 (pnp = (Ph2PCH2)2NPh) with (dppv)Fe(CO)2(pdt) (dppv = 1,2-(Ph2P)2C2H2, pdt = 1,3-propanedithiolate) and KPF6 gave the dicarbonyl complex [(pnp)Ni(pdt)Fe(CO)2(dppv)](PF6)2 ([1](PF6)2). Further treatment of [1](PF6)2 and [(dppe)Ni(pdt)Fe(CO)2(dppv)](BF4)2 (dppe = 1,2-(Ph2P)2C2H4) with the decarbonylation agent Me3NO and pyridine afforded the novel sp3 C-Fe bond-containing complexes [(pnp)Ni(SCH2CH2CHS)Fe(CO)(dppv)]PF6 ([2]PF6) and [(dppe)Ni(SCH2CH2CHS)Fe(CO)(dppv)]BF4 ([3]BF4). More interestingly, the first t-carboxylato complexes [(pnp)Ni(pdt)Fe(CO)(t-O2CR)(dppv)]PF6 ([4]PF6, R = H; [5]PF6, R = Me; [6]PF6, R = Ph) could be prepared by reactions of [1]PF6 with the corresponding carboxylic acids RCO2H in the presence of Me3NO, whereas further reactions of [4]PF6-[6]PF6 with aqueous HPF6 and 1.5 MPa H2 gave rise to the µ-hydride complex [(pnp)Ni(pdt)Fe(CO)(µ-H)(dppv)]PF6 ([7]PF6). Except for H2 activation by t-carboxylato complexes [4]PF6-[6]PF6 to give a µ-hydride complex ([7]PF6), the sp3 C-Fe bond-containing complex [2]PF6 was found to be a catalyst for proton reduction to H2 under CV conditions. Furthermore, the chemical reactivity of the µ-hydride complex [7]PF6 displayed in the e- transfer reaction with FcPF6 in the presence of CO, the H2 evolution reaction with the protonic acid HCl, and the H- transfer reaction with N-methylacridinium hexafluorophosphate ([NMA]PF6) was systematically studied. As a result, a series of the expected products such as H2, ferrocene, the dicarbonyl complex [1](PF6)2, the µ-chloro complex [(pnp)Ni(pdt)Fe(CO)(µ-Cl)(dppv)]PF6 ([8]PF6), the t-MeCN-coordinated complex [(pnp)Ni(pdt)Fe(CO)(t-MeCN)(dppv)](PF6)2 ([9](PF6)2) and the H- transfer product AcrH2 were produced. While all the newly prepared model complexes were structurally characterized by spectroscopic methods, the molecular structures of some of their representatives were confirmed by X-ray crystallography.

Metatranscriptome of human lung microbial communities in a cohort of mechanically ventilated COVID-19 Omicron patients.

The Omicron variant of the severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) infected a substantial proportion of Chinese population, and understanding the factors underlying the severity of the disease and fatality is valuable for future prevention and clinical treatment. We recruited 64 patients with invasive ventilation for COVID-19 and performed metatranscriptomic sequencing to profile host transcriptomic profiles, plus viral, bacterial, and fungal content, as well as virulence factors and examined their relationships to 28-day mortality were examined. In addition, the bronchoalveolar lavage fluid (BALF) samples from invasive ventilated hospital/community-acquired pneumonia patients (HAP/CAP) sampled in 2019 were included for comparison. Genomic analysis revealed that all Omicron strains belong to BA.5 and BF.7 sub-lineages, with no difference in 28-day mortality between them. Compared to HAP/CAP cohort, invasive ventilated COVID-19 patients have distinct host transcriptomic and microbial signatures in the lower respiratory tract; and in the COVID-19 non-survivors, we found significantly lower gene expressions in pathways related viral processes and positive regulation of protein localization to plasma membrane, higher abundance of opportunistic pathogens including bacterial Alloprevotella, Caulobacter, Escherichia-Shigella, Ralstonia and fungal Aspergillus sydowii and Penicillium rubens. Correlational analysis further revealed significant associations between host immune responses and microbial compositions, besides synergy within viral, bacterial, and fungal pathogens. Our study presents the relationships of lower respiratory tract microbiome and transcriptome in invasive ventilated COVID-19 patients, providing the basis for future clinical treatment and reduction of fatality.

Biomimetic models for the active site of [Fe]hydrogenase featuring an acylmethyl(hydroxymethyl)pyridine ligand.

The first acylmethyl(hydroxymethyl)pyridine ligand-containing [Fe]hydrogenase model complexes 2-4 have been synthesized starting from the nucleophilic substitution reaction of 2-(4-MeC(6)H(4)SO(3)CH(2))-6-HOCH(2)C(5)H(3)N with Na(2)Fe(CO)(4). While the reaction course for producing complex 3 via the highly unstable intermediate complex 1 is monitored by in situ IR spectroscopy, the isolated model complexes 2-4 are fully characterized.

Biomimetic models of [Fe]-hydrogenase featuring a 2-acylphenylthiomethyl-6-R-pyridine (R = H or OMe) ligand.

Despite a variety of [Fe]-H2ase models prepared so far, the structural and functional modeling study of the enzyme has remained a great challenge. Now, we report a new type of flexible pyridine ligand (FPL)-based synthetic method by which two novel [Fe]-H2ase models have been prepared. Notably, the two models contain not only a biomimetic fac-acyl C, pyridyl N, thioether S coordination mode but also possess the enzyme-like H2/D2 activation functions.

Potential roles of vitamin D binding protein in attenuating liver injury in sepsis.

BACKGROUND: In sepsis, vitamin D binding protein (VDBP) has been shown to be low-expressed. The current study examined the relationship between serum VDBP level and liver injury in sepsis patients, as well as in a mouse model for sepsis and in cultured liver epithelial cell line exposed to lipopolysaccharide (LPS). METHODS: The human study included 78 sepsis patients and 50 healthy volunteers. Sepsis patients were categorized into sepsis survivor group (n = 43) and sepsis non-survivor group (n = 35) based on 28-day mortality for data analysis. Adult male C57BL/6 mice were subjected to cecal ligation and puncture (CLP). Serum samples were collected on day 1, 3, 5 and 7 to determine the levels of VDBP, 25-hydroxyvitamin D [25(OH)D3], 1,25-dihydroxyvitamin D [1,25(OH)2D3], interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α). Potential protective effects of VDBP overexpression against LPS-induced liver damage were examined in cultured THLE2 cells. RESULTS: Serum levels of VDBP, 25(OH)D3, and 1,25(OH)2D3 were significantly lower in sepsis patients vs. the healthy control (P < 0.001), as well as in the sepsis non-survivor group vs. the sepsis survivor group (P < 0.001, P = 0.0338, or P = 0.0013, respectively). Lower serum VDBP level was associated with higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (r = - 0.2565, P = 0.0234) and Sequential Organ Failure Assessment score (r = - 0.3522, P = 0.0016), but lower serum albumin (ALB, r = 0.4628, P < 0.001) and total protein (TP, r = 0.263, P = 0.02). In CLP mice, there was a 5-day period of serum VDBP reduction, followed by return towards the baseline on day 7. VDBP was also decreased in LPS-treated THLE2 cells (P < 0.001). VDBP overexpression reduced LPS-induced THLE2 damage. Reduced damage was associated with decreased oxidative stress and inactivation of the c-Jun N-terminal kinase signaling pathway. CONCLUSION: VDBP may be protective against sepsis-induced liver injury.

Synthesis and structural characterization of some new porphyrin-fullerene dyads and their application in photoinduced H2 evolution.

The [3 + 2] cycloaddition reaction of C(60) with ethyl isonicotinoylacetate in the presence of piperidine in PhCl at room temperature or in the presence of Mn(OAc)(3) in refluxing PhCl gave the pyridyl-containing dihydrofuran-fused C(60) derivative (4-C(5)H(4)N)C(O)═C(C(60))CO(2)Et (1), whereas the phenyl-containing C(60) derivative PhC(O)═C(C(60))CO(2)Et (2) was similarly prepared by [3 + 2] cycloaddition reaction of C(60) with ethyl benzoylacetate in the presence of piperidine or Mn(OAc)(3). More interestingly, one of the new porphyrin-fullerene dyads, i.e., [4-C(5)H(4)NC(O)═C(C(60))CO(2)Et]·ZnTPPH (3, ZnTPPH = tetraphenylporphyrinozinc), could be prepared by coordination reaction of the pyridyl-containing C(60) derivative 1 with equimolar ZnTPPH in CS(2)/hexane at room temperature. In addition, the ß-keto ester-substituted porphyrin derivative H(2)TPPC(O)CH(2)CO(2)Et (4) was prepared by a sequential reaction of HO(2)CCH(2)CO(2)Et with n-BuLi in 1:2 molar ratio followed by treatment with H(2)TPPC(O)Cl in the presence of Et(3)N and then hydrolysis with diluted HCl, whereas the porphyrinozinc derivative ZnTPPC(O)CH(2)CO(2)Et (5) could be prepared by coordination reaction of 4 with Zn(OAc)(2) in refluxing CHCl(3)/MeOH. Particularly interesting is that the second new porphyrin-fullerene dyad H(2)TPPC(O)═C(C(60))CO(2)Et (6) could be prepared by [3 + 2] cycloaddition reaction of 4 with C(60) in the presence of piperidine in PhCl at room temperature. In addition, treatment of 6 with Zn(OAc)(2) in refluxing CHCl(3)/MeOH afforded the third new dyad ZnTPPC(O)═C(C(60))CO(2)Et (7). All the new compounds 1-7 were characterized by elemental analysis and various spectroscopic methods and particularly for 2, 3, and 5 by X-ray crystallography. The five-component system consisting of an electron donor EDTA, dyad 3, an electron mediator methylviologen (MV(2+)), the catalyst colloidal Pt, and a proton source HOAc was proved to be effective for photoinduced H(2) evolution. A possible pathway for such a type of H(2) evolution was proposed.

Synthetic and structural investigations of linear and macrocyclic nickel/iron/sulfur cluster complexes.

Three series of new Ni/Fe/S cluster complexes have been prepared and structurally characterized. One series of such complexes includes the linear type of (diphosphine)Ni-bridged double-butterfly Fe/S complexes [(µ-RS)(µ-S═CS)Fe(2)(CO)(6)](2)[Ni(diphosphine)] (1-6; R = Et, t-Bu, n-Bu, Ph; diphosphine = dppv, dppe, dppb), which were prepared by reactions of monoanions [(µ-RS)(µ-CO)Fe(2)(CO)(6)](-) (generated in situ from Fe(3)(CO)(12), Et(3)N, and RSH) with excess CS(2), followed by treatment of the resulting monoanions [(µ-RS)(µ-S═CS)Fe(2)(CO)(6)](-)with (diphosphine)NiCl(2). The second series consists of the macrocyclic type of (diphosphine)Ni-bridged double-butterfly Fe/S complexes [µ-S(CH(2))(4)S-µ][(µ-S═CS)Fe(2)(CO)(6)](2)[Ni(diphosphine)] (7-9; diphosphine = dppv, dppe, dppb), which were produced by the reaction of dianion [{µ-S(CH(2))(4)S-µ}{(µ-CO)Fe(2)(CO)(6)}(2)](2-) (formed in situ from Fe(3)(CO)(12), Et(3)N, and dithiol HS(CH(2))(4)SH with excess CS(2), followed by treatment of the resulting dianion [{µ-S(CH(2))(4)S-µ}{(µ-S═CS)Fe(2)(CO)(6)}(2)](2-) with (diphosphine)NiCl(2). However, more interestingly, when dithiol HS(CH(2))(4)SH (used for the production of 7-9) was replaced by HS(CH(2))(3)SH (a dithiol with a shorter carbon chain), the sequential reactions afforded another type of macrocyclic Ni/Fe/S complex, namely, the (diphosphine)Ni-bridged quadruple-butterfly Fe/S complexes [{µ-S(CH(2))(3)S-µ}{(µ-S═CS)Fe(2)(CO)(6)}(2)](2)[Ni(diphosphine)](2) (10-12; diphosphine = dppv, dppe, dppb). While a possible pathway for the production of the two types of novel metallomacrocycles 7-12 is suggested, all of the new complexes 1-12 were characterized by elemental analysis and spectroscopy and some of them by X-ray crystallography.

Heterodinuclear nickel(ii)-iron(ii) azadithiolates as structural and functional models for the active site of [NiFe]-hydrogenases.

To develop the biomimetic chemistry of [NiFe]-H2ases, the first azadithiolato-bridged NiFe model complexes [CpNi{(µ-SCH2)2NR}Fe(CO)(diphos)]BF4 (5, R = Ph, diphos = dppv; 6, 4-ClC6H4, dppv; 7, 4-MeC6H4, dppv; 8, CO2CH2Ph, dppe; 9, H, dppe) have been synthesized via well-designed synthetic routes. Thus, treatment of RN[CH2S(O)CMe]2 with t-BuONa followed by reaction of the resulting intermediates RN(CH2SNa)2 with (dppv)Fe(CO)2Cl2 or (dppe)Fe(CO)2Cl2 gave the N-substituted azadithiolato-chelated Fe complexes [RN(CH2S)2]Fe(CO)2(diphos) (1, R = Ph, diphos = dppv; 2, 4-ClC6H4, dppv; 3, 4-MeC6H4, dppv; 4, CO2CH2Ph, dppe). Further treatment of 1-4 with nickelocene in the presence of HBF4·Et2O afforded the corresponding N-substituted azadithiolato-bridged NiFe model complexes 5-8, while treatment of 8 with HBF4·Et2O resulted in formation of the parent azadithiolato-bridged model complex 9. While all the new complexes 1-9 were characterized by elemental analysis and spectroscopy, the molecular structures of model complexes 6-8 were confirmed by X-ray crystallographic study. In addition, model complexes 7 and 9 were found to be catalysts for H2 production with moderate i cat/i p and overpotential values from TFA under CV conditions.

Synthetic and structural studies on L-cysteinyl group-containing diiron/triiron azadithiolates as active site models of [FeFe]-hydrogenases.

Five new L-cysteinyl group-containing diiron/triiron azadithiolate complexes (3-6, 10), which could be regarded as the active site models of [FeFe]-hydrogenases, have been successfully synthesized. Treatment of L-cysteinyl sodium mercaptide CytSNa (1, Cyt = CH(2)CH(CO(2)Et)NH(CO(2)Bu-t) with complex [(mu-SCH(2))(2)NCH(2)CH(2)Br]Fe(2)(CO)(6) (2) in THF at room temperature resulted in formation of model complex [(mu-SCH(2))(2)NCH(2)CH(2)SCyt]Fe(2)(CO)(6) (3). Further treatment of 3 with decarbonylating agent Me(3)NO in MeCN at room temperature afforded model complex [(mu-SCH(2))(2)NCH(2)CH(2)SCyt]Fe(2)(CO)(5) (4). Similarly, treatment of 3 with an equimolar mixture of Me(3)NO and Ph(3)P gave model complex [(mu-SCH(2))(2)NCH(2)CH(2)SCyt]Fe(2)(CO)(5)(Ph(3)P) (5) and further treatment of 5 with Me(3)NO produced model complex [(mu-SCH(2))(2)NCH(2)CH(2)SCyt]Fe(2)(CO)(4)(Ph(3)P) (6). More interestingly, model complex [(mu-SCH(2))(2)NCH(CO(2)Et)CH(2)SFe(CO)(2)Cp]Fe(2)(CO)(5) (10) could be synthesized by a "one pot" reaction of the in situ prepared (mu-HS)(2)Fe(2)(CO)(6) (9) with 37% aqueous formaldehyde followed by treatment with the N-deprotected L-cysteinyl iron mercaptide Cp(CO)(2)FeSCH(2)CH(CO(2)Et)NH(2) (8). Complex 8 is new, which was prepared by treatment of complex Cp(CO)(2)FeSCyt (7) with CF(3)CO(2)H followed by 25% aqueous NH(3). All the new complexes 3-6, 8, and 10 were characterized by elemental analysis and various spectroscopic techniques, whereas complexes 5 and 10 were further characterized by X-ray crystallography.

Hydrophilic quaternary ammonium-group-containing [FeFe]H2ase models prepared by quaternization of the pyridyl N atoms in pyridylazadiphosphine- and pyridylmethylazadiphosphine-bridged diiron complexes with various electrophiles.

The first aromatic quaternary ammonium-group-containing [FeFe]H2ase models have been prepared by a simple and convenient two-step method in high yields. Thus, on the basis of preparation of the N-pyridylazadiphosphine-bridged diiron complex (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NC5H4N] (A) by CO substitution of parent complex (µ-PDT)Fe2(CO)6 with N-pyridylazadiphosphine 3-(Ph2P)2NC5H4N in refluxing xylene, further quaternization of the pyridyl N atom in complex A with electrophile 1,3-propanesultone, 1,3,2-dioxathiolane-2,2-dioxide, or 4-bromobutyric acid in refluxing MeCN afforded the pyridyl quaternary ammonium-group-containing models (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NC5H4NR] (1, R = (CH2)3SO3; 2, R = (CH2)2OSO3) and (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NC5H4N(CH2)3CO2H]Br (3). Similarly, the N-pyridylmethylazadiphosphine-bridged diiron complex (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NCH2C5H4N] (B) could be prepared by CO substitution of parent complex (µ-PDT)Fe2(CO)6 with N-pyridylmethylazadiphosphine 3-(Ph2P)2NCH2C5H4N in refluxing xylene, while further quaternization of the pyridylmethyl N atom in complex B with 1,3-propanesultone and 3-bromo-1-propanol in MeCN at reflux resulted in formation of the pyridylmethyl quaternary ammonium-group-containing models (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NCH2C5H4N(CH2)3SO3] (4) and (µ-PDT)Fe2(CO)4[µ-3-(Ph2P)2NCH2C5H4N(CH2)3OH]Br (5), respectively. All new complexes A, B, and 1-5 were characterized by elemental analysis and various spectroscopies, while the molecular structures of complexes A, B, 2 and 5 were further confirmed by X-ray crystallography. The electrochemical study on hydrophilic models 1 and 3 in MeCN and the MeCN/H2O mixed solvent indicated that the reduction potentials were shifted to less-negative potentials as the water content increased; such an observation implies that both 1 and 3 are easily reduced in the mixed MeCN/H2O solvent than in MeCN. In addition, the electrocatalytic study demonstrated that both 1 and 3 can serve as electrocatalysts for H2 production from acetic acid with higher icat/ip and TONs in MeCN/H2O than in MeCN.

NADPH Oxidase Isoforms Are Involved in Glucocorticoid-Induced Preosteoblast Apoptosis.

Oxidative stress induced by long-term glucocorticoid (GC) use weakens the repair capacity of bone tissue. Nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) oxidase (NOX) is a superoxide-generating enzyme that plays an important role in regulating bone metabolism. To clarify the role of nonphagocytic NOX isoforms in osteoblast reactive oxygen species (ROS) generation and apoptosis, dexamethasone was used to establish a high-dose GC environment in vitro. A dose-dependent increase in intracellular ROS generation was demonstrated, which was accompanied by increased osteoblastic MC3T3-E1 cell apoptosis. Addition of the ROS inhibitor NAC (N-acetyl-L-cysteine) or NOX inhibitor DPI (diphenyleneiodonium) reversed this effect, indicating that NOX-derived ROS can induce osteoblast apoptosis under high-dose dexamethasone stimulation. NOX1, NOX2, and NOX4 are NOX homologs recently identified in bone tissue. To clarify the NOX isoforms that play a role in osteoblast ROS generation, Nox1, Nox2, and Nox4 mRNA expression and NOX2 and NOX4 protein expression were analyzed. Nox1 and Nox4 mRNA expression was elevated in a dose-dependent manner after culture in 100 nM, 250 nM, 500 nM, or 1000 nM dexamethasone, and the increased expression of NOX1 mRNA was more significant compared with NOX4 mRNA. Small interfering RNAs (siRNAs) were used to confirm the role of NOX1 and NOX4 in ROS generation. To clarify the signaling pathway in ROS-induced osteoblast apoptosis, mitogen-activated protein kinase (MAPK) signaling molecules were analyzed. Phosphorylated ASK1 and p38 levels were significantly higher in the 1000 nM dexamethasone group, which NAC or DPI markedly attenuated. However, the total mRNA and protein levels of ASK1 and p38 between the dexamethasone group and control were not significantly different. This is related to ROS regulating the posttranslational modification of ASK1 and p38 in MC3T3-E1 cell apoptosis. Altogether, NOX1- and NOX4-derived ROS plays a pivotal role in high-dose dexamethasone-induced preosteoblast apoptosis by increasing phosphorylated ASK1 and p38 and may be an important mechanism in steroid-induced avascular necrosis of the femoral head (SANFH).

Incidence and risk factors of postoperative delirium in the elderly patients with hip fracture.

BACKGROUND: To investigate the incidence and related risk factors of delirium in elderly patients with hip fracture. METHODS: This is a retrospective study, performed in a medical center from October 2014 to February 2017, which enrolled all subjects aged over 65 years who were admitted for hip surgeries (hip arthroplasty, proximal femoral nail fixation). Univariate and multivariate logistic analysis was used to determine the incidence and risk factors of delirium. Delirium was assessed according to the Confusion Assessment Method (CAM). RESULTS: Overall, 19.29% of total 306 patients (mean age 81.9 ± 5.4 years) were identified as delirium. The delirium was significantly associated (p < 0.05) with the factors of age, hospitalization, diabetes, preoperative hematocrit (HCT), perioperative protein consumption, transfusion volume, preoperative leukocyte level, albumin level, American Society of Anesthesiologists (NYHA) classification, American Society of Anesthesiologists (ASA) classification, blood loss, coronary heart disease, and cerebral infarction. Multivariate analysis of the variables confirmed that age (> 75 years old), diabetes, and ASA classification (> 2 level) are the independent risk factors of postoperative delirium (POD). In addition, patients in delirium had prolonged hospitalization and high perioperative albumin infusion. CONCLUSION: The elderly patients over the age of 75 years with the history of diabetes or ASA classification > 2 level were at higher risk of POD. Delirium is an important postoperative complication, which had prolonged hospitalization and high perioperative albumin infusion. LEVEL OF EVIDENCE: III.

Synthesis, characterization, and electrochemical properties of mono-, di-, and trinuclear transition Metal [60]fullerene complexes containing diphosphine cis-Ph2PCH=CHPPh2 ligand.

New transition metal fullerene complexes containing cis-Ph2PCH=CHPPh2 (dppet) ligand have been investigated. The mononuclear complexes (etau2-C60)M(cis-dppet) (1, 2; M = Pd, Pt) were prepared by reaction of C60 with M(dba)2 (dba = dibenzylideneacetone) followed by treatment with cis-dppet, while the in situ prepared 1 and 2 reacted with M1(PPh3)4 to afford dinuclear complexes (eta2 : eta2-C60)M(cis-dppet)M1 (PPh3)2 (3-6; M, M1 = Pd, Pt). Similarly, trinuclear complexes (eta2 : eta2-C60) M(cis-dppet)M1 (dppr) (7-10; M, M1 = Pd, Pt; dppr = (eta5-Ph2PC5H4)2Ru) could be synthesized by reaction of the in situ prepared 3-6 with dppr. 1-10 were characterized by elemental analysis and spectroscopy. Cyclic voltammetric studies on 2 (M = Pt), 3 (M = Pd, M1 = Pd) and 9 (M = Pt, M1 = Pd) provided further evidence for the eta2-coordination of C60 to one metal fragment or two metal fragments in these complexes.