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In the polymeric complex of the title compound, {[AgNi(C5H3N2O2)2(H2O)2]NO3·2H2O}n, the AgI ion displays an angular coordination geometry with two N atoms from pyrazine-2-carboxylate ligands, and the NiII ion is hexacoordinated by two O atoms from two water molecules, two O and two N atoms from pyrazine-2-carboxylate ligands in a distorted octahedral geometry. In the crystal, the AgI and NiII ions lie on a mirror plane and an inversion centre, respectively. The complex chains, the nitrate ions and the uncoordinated water molecules are linked together through O—H...O hydrogen bonds and weak Ag...O interactions [2.619 (17)–2.749 (17) Å] into a three-dimensional network.

The reactions of titanyl sulfate with PO(sub 4)(super 3-), P(sub 2)O(sub 7)(super 4-), and Cr(sub 2)O(sub 7)(super 2-) in the presence of L(sub OEt)(super -) in aqueous media are studied. The reactions with PO(sub 4)(super 3-) and P(sub 2)O(sub 7)(super 4-) gave the corresponding oxo-bridged phosphato complexes whereas that with Cr(sub 2)O(sub 7)(super 2-) afforded a dinuclear complex containing a Ti(sub 2)(CrO(sub 4)) core.

Four mixed-valent ruthenium diphosphonates were synthesized and structurally characterized. Magnetic studies show that significant antiferromagnetic exchange are mediated between the [Ru2(hedp2)](super 3-) (S=3/2) units through halide bridges in compounds, Na4[Ru(hedp)2X].16H2O and K3[Ru(hedp)2.(H2O)2].6H2O.

Study presents synthesis and characterization of a ruthenium(VI) nitrido compound containing the oxygen tripodal ligand. The ruthenium(VI) nitrido compound was found to be electrophilic and reacted with PPh3, Me3NO, and S2[O.sub.3.sup.2-] to give phosphiniminato, nitrosyl, and thionitrosyl compounds respectively.

Six diruthenium, diphosphonates are synthesized under hydrothermal conditions in the presence of organic templates. Compounds [[H.sub.3]N[C[H.sub.2].sub.3]N[H.sub.3]2[[Ru.sub.2][(hedp).sub.2]] and [H.sub.3]N[C[H.sub.2].sub.5]N[H.sub.3]2[[Ru.sub.2]-[(hedp).sub.2]].4[H.sub.2]O exhibit analogous linear chain structures with the protonated organic diammonium cations locate between the chains.

Research has been conducted on mixed valence ruthenium(II,III) compound. The authors describe the synthesis and crystal structure of the compound, and report that the compound has the two-dimensional structure with the paddlewheel diruthenium(II,III) units which are cross-linked via phosphonate groups.

Endoscopic mucosal resection (EMR) was originally described in 1973 and is currently a popular practice used in treating polyps, small adenomas, and early cancers. Although the safety of EMR has been proven in numerous studies, complications occur occasionally. We report a case in which the patient complained of severe upper abdominal pain and who was diagnosed with acute appendicitis after colorectal EMR. The patient recovered well after surgery. Cautious observation is necessary when resuming oral intake in patients who undergo colorectal EMR and who complain of postoperative abdominal pain. Observation is especially important for patients with a fecalith that may have originally existed in the appendix or in the colon near the appendix.

Abstract Background Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication. Methods Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression. Result In multivariable analysis, age (OR 1.081, 95% CI, 1.047–1.117), BMI (OR 1.233, 95% CI, 1.116–1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829–8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325–6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632–7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963–5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086–1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003–1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068–0.785) was independent protective factor of FDGE. Conclusion Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.

Abstract Background The status of lymph nodes in early gastric cancer is critical to make further clinical treatment decision, but the prediction of lymph node metastasis remains difficult before operation. This study aimed to develop a nomogram that contained preoperative factors to predict lymph node metastasis in early gastric cancer patients. Methods This study analyzed the clinicopathologic features of 823 early gastric cancer patients who underwent gastrectomy retrospectively, among which 596 patients were recruited in the training cohort and 227 patients in the independent validation cohort. Significant risk factors in univariate analysis were further identified to be independent variables in multivariable logistic regression analysis, which were then incorporated in and presented with a nomogram. And internal and external validation curves were plotted to evaluate the discrimination of the nomogram. Results Totally, six independent predictors, including the tumor size, macroscopic features, histology differentiation, P53, carbohydrate antigen 19-9, and computed tomography-reported lymph node status, were enrolled in the nomogram. Both the internal validation in the training cohort and the external validation in the validation cohort showed the nomogram had good discriminations, with a C-index of 0.82 (95%CI, 0.78 to 0.86) and 0.77 (95%CI, 0.60 to 0.94) respectively. Conclusions Our study developed a new nomogram which contained the most common and significant preoperative risk factors for lymph node metastasis in patients with early gastric cancer. The nomogram can identify early gastric cancer patients with the high probability of lymph node metastasis and help clinicians make more appropriate decisions in clinical practice.

Reaction of deprotonated 2,5-bis(2'-pyridyl)pyrrole (HPDPH) with AgOTf (where OTf- = triflato) in THF readily yields a yellow triangular Ag]3 complex [(PDPH)Ag]3 (1), of which the av. Ag...Ag distance is 2.902 Å. A mixture of HPDPH and AgOTf reacts with PPh]3 to afford a linear Ag]3 complex [Ag{(PDPH)Ag(PPh]3)}]2]- (OTf) (2.OTf), whereas it reacts with diethyl phosphite in the presence of Li[N(SiMe]3)]2] to yield a dinuclear complex Li]2[(PDPH)Ag]2{P(O)(OEt)]2}]2](OTf) (Li]2.3.OTf). In 2, the terminal Ag atoms are three coordinate containing one phosphorous atom from PPh]3 and two nitrogen atoms of the PDPH ligand. The center Ag atom is only two coordinate, binding to the residued pyridyl N atom of the PDPH ligand. In 3, two silver atoms are bridged by one PDPH ligand. Treatment of PDPH with CuCl in the presence of NaH afforded a heterobimetallic copper-sodium complex [Cu(PDPH)]2Na(thf)]2] (4). The PDPH ligand in 1-4 is nonplanar, with torsion angles between pyridine and pyrrole rings in the range of 15.8-38.3°. The argentophilic interactions, π...π stacking, and weak interaction of Ag...C(aromatic) are observed in these complexes. Interestingly, treatment of the analogous 2,5-bis(6'-bromo-2'-pyridyl)-pyrrole (HPDPBr) with AgOTf affords a di-nuclear complex [(HPDPBr)Ag]]2(OTf)]2 (5.(OTf)]2). Its HPDPBr ligands coordinate to Ag atoms in a head-to-head fashion, and two protonated pyrrole linkages reside in the anti-parallel direction and are non-coordinating. Short Ag...Br distances of 3.255-3.390 Å are observed. [ABSTRACT FROM AUTHOR]

Dinuclear ruthenium nitrido complexes supported by the Klaui's tripodal ligand [CpCo{P(O)(OEt)₂}₃]⁻ (LOEt⁻) have been synthesized starting from the ruthenium(VI) nitrido precursor [LOEt,RuVI(N)Cl₂] (1). Heating a solution of 1 in CC1₄ at reflux, followed by recrystallization from hexane under nitrogen, afforded the mixed-valence ruthenium(V) --ruthenium(IV) μ-nitrido complex [LOEtCl₂RuV(μ-N)RuIVCl₂LOHt] (2). The cyclic voltammogram of 2 exhibited reversible couples at 0.19 and 1.13 V versus Cp₂Fe+/O, which are assigned as the RuV-RuIV/RurV-RuIV and RuV--RuV/RuV--RuIV couples, respectively. Recrystallization of 2 from Et₂O/heptane in air yielded the diamagnetic RuIV-- RuIV complex [H13O₂][{LOEtRuIVCl₂}₂(μ-N)] ([H13O₂][2]), which underwent cation exchange with n-Bu₄NOH to give [n-Bu₄N][2]. X-ray diffraction revealed that the complex anions in [H13O₆][2] and [n-Bu₄N][2] contain linear, symmetric Ru--N--Ru bridges. Treatment of 1 with [(η₆-p-cymene)Ru11Cl₂]₂ in benzene afforded the tetranudear ruthenium(IV) complex [LOEtCl₂RuIV(μ-N)RuIV(H₂O)Cl₂]₂ (3) containing symmetric RuIV-- N--RuIV bridges. The reaction of 1 with [Ru11(H)(Cl)(CO)(PCy₃)₂] (Cy = cycloheiyl) gave the ruthenium(VI)-ruthenium(II) nitrido complex [LOEtCl₂RuVI(μ-N)Ru11(H)Cl(CO)(PCy₂)₂] (4). The observed short Ru11-N bond distance [1.915(5) Å] and high C--O stretching frequency (1985 cm-1) in 4 are suggestive of π interaction between Ru11 and the nitride. [ABSTRACT FROM AUTHOR]

Treatment of [Ru(ᆖCHR)Cl2(PCy3)2] (Cy = cyclohexyl) with Tl[N(Pr2iPO)2] and AgLOEt (LOEt− = [CpCo{P(O)(OEt)2}3]−) afforded the Ru carbene complexes [Ru(ᆖCHPh)(PCy3)Cl{N(Pr2iPO)2}] (1) and [LOEtRu(ᆖCHR)(PCy3)Cl] (2), respectively. Chloride abstraction of complex 2 with TlPF6 in MeCN afforded [LOEtRu(ᆖCHPh)(PCy3)(MeCN)][PF6] (3). Complexes 1 and 2 are capable of catalyzing ring-closing metathesis of diethyl 1,2-diallylmalonate. The crystal structure of complex 2 has been determined. [ABSTRACT FROM AUTHOR]

Bismuth(III) compounds containing the Kläui's oxygen tripodal ligand [CpCo{P(O)(OEt)2}3]- (LOEt-) have been synthesized, and their interactions with dichromate in aqueous media were studied. The treatment of Bi5O(OH)9(NO3)4 with NaLOEt in water afforded [LOEtBi(NO3)2]2 (1), whereas that of BiCl3 with NaLOEt in CH2Cl2 yielded LOEtBiCl2 (2). Chloride abstraction of 2 with AgX afforded [LOEtBiX2]2 [X- = triflate (OTf-) (3), tosylate (OTs-) (4)]. In aqueous solutions at pH > 4, 4 underwent ligand redistribution to give the bis(tripod) complex [(LOEt)2Bi(H2O)][OTs] (5). The treatment of 4 with Na2Cr2O7 in acetone/water afforded the Bi(III)/Cr(VI) oxo cluster [(LOEt)4Bi4(μ3-CrO4)2(μ3-Cr2O7)2] (6) containing a unique Bi4Cr4O12 oxometallic core. Compound 6 oxidized benzyl alcohol to give ca. 6 equiv of benzaldehyde. The reaction between 2 and CrO3 yielded [LOEtBi(OCrO2Cl)]2(μ-Cl)2 (7). The crystal structures of complexes 4-7 have been determined. [ABSTRACT FROM AUTHOR]

Three pH/temperature-dependent 2D MOFs containing 1D nanotubular meso-helical chains were firstly synthesized from multidentate 2,4ˈ-H2bpdc. Crystal structure analysis shows that 2and 3are monochiral and the resultant crystals were not racemic as evidenced by the observation of strong signals in vibrational circular dichroism (VCD) and circular dichroism (CD) spectra. [ABSTRACT FROM AUTHOR]

Treatment of [(LOEt)2Ti2(μ-O)2(μ-SO4)] (LOEt−= [(η5-C5H5)Co{P(O)(OEt)2}3]−) with [Ru(H)(Cl)(CO)(PPh3)3] and Ag(OTf) (OTf−= triflate) in the presence of Na2CO3gave the TiIV–RuIIcomplex [(LOEt)2Ti2(μ-O)3(μ3-SO4)Ru(CO)(PPh3)2] (2) whereas that with [Re(CO)5(OTf)] afforded the TiIV–ReIcomplex [H(LOEt)2Ti2(μ-O)3(μ-SO4)Re(CO)3(H2O)] (3). The crystal structures of complexes 2·HOTf and [3·2/3(Et3NHOTf)·5/12(H2O)]3have been determined. Complex 2consists of an adamantane-like Ti2RuSO6core, in which the {RuII(PPh3)2(CO)} moiety is facially coordinated to a tridentate-O,O′,O′′(sulfate) [(LOEt)2Ti2(μ-O)3(μ3-SO4)]2−metalloligand. The anion [(LOEt)2Ti2(μ-O)3(μ-SO4)Re(CO)3(H2O)]−in 3can be viewed as consisting of a fac-{ReI(CO)3} fragment coordinated with one aqua ligand and a bidentate-O,O′-[(LOEt)2Ti2(μ-O)3(μ-SO4)]2−metalloligand. [ABSTRACT FROM AUTHOR]

Self-assemblies of two unsymmetrical tridentate N2O/N2S donor Schiff base ligands, that is, 2-((2-(dimethylamino)ethylimino)methyl)phenol (HL1) and methyl-2-pyridylmethylidenehy-drazinecarbodithioate (HL2), with different cadmium salts have led to 11 anion-controlled complexes, namely, [Cd(Ln)2] [n= 1 for 1and n= 2 for 2], [Cd(L1)(HL1)](ClO4) (3), [Cd(HL2)(L2)](ClO4)(H2O) (4), [Cd(L2)Cl2] (5), [Cd(L1)Cl]2(6), [Cd(L1)(NO3)]2(7), [Cd(L2)(NO3)(CH3OH)]2(8), [Cd(L2)(NO3)(H2O)]2(8a), [Cd2(L1)2(SCN)2]n(9), and [CdL2(SCN)2]n(10), respectively. Eleven compounds were characterized by elemental analyses, IR spectra, MS and thermogravimetric analyses, of which 10 structures 2, 3, 4, 5, 6, 7, 8, 8a, 9, and 10were further determined by single-crystal X-ray diffraction analyses. The compounds 2, 3, and 4are mononuclear, in which the neutral molecule unit CdII(L2)2(in 2) as well as cation units [CdII(HL1−2)(L1−2)](L1for 3and L2for 4) are respectively connected by hydrogen bonds C−H···S, O−H···O, and C−H···O and form three-dimensional (3D) ordered network structures. With the replacement of Cd(CH3COO)2/Cd(ClO4)2by CdCl2/Cd(NO3)2in the above reactions, because of the coordination interactions of nitrate and chloride anions in these cases, the obtained corresponding compounds 6−8present dinuclear structures with planar Cd2O2/Cd2S2quadrilateral cores and only compound 5mononuclear, in which the folding effect of sulfur and solvent effect, to a certain extent, affect the microstructure of these complexes, such as the arrangements of the ligand L1−2and nitrate/chloride ions. Furthermore, through intermolecular weak interactions, for example, C−H···O, O−H···N hydrogen bonding and π···πstacking, 3D supramolecular structures are assembled in these compounds. However, reactions of Cd(CH3COO)2/Cd(ClO4)2 KSCN with L (L = L1(9), L2(10)) yield two one-dimensional (1D) chain-like compounds, and similarly, via interchain hydrogen bonds C−H···S (for 9) and N−H···N (for 10), 2D layer-like supramolecular networks are constructed. In addition, the photoluminescent properties of two ligands as well as 11 compounds were also studied. [ABSTRACT FROM AUTHOR]

The treatment of [Ru(LOEt)(N)Cl2] (1; LOEt- = [Co(η5-C5H5){P(O)(OEt)2}3]-) with Et3SiH affords [Ru(LOEt)Cl2(NH3)] (2), whereas that with [Ru(LOEt)(H)(CO)(PPh3)] (3) gives the dinuclear imido complex [(LOEt)Cl2Ru(μ-NH)Ru(CO)(PPh3)(LOEt)] (4). The imido group in 4 binds to the two ruthenium atoms unsymmetrically with Ru-N distances of 1.818(6) and 1.952(6) Å. The reaction between 1 and 3 at 25 °C in a toluene solution is first order in both complexes with a second-order rate constant determined to be (7.2 ± 0.4) × 10-5 M-1 s-1. [ABSTRACT FROM AUTHOR]

Interaction of [Ce(LOEt)2(NO3)2] (LOEt− = [Co(η5-C5H5){P(O)(OEt)2}3]−) with (NH4)6[Mo7O24] in water affords the cerium(iv)-containing oxomolybdenum cluster [H4(CeLOEt)6Mo9O38], which exhibits a unique Ce6Mo9O38 core structure. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is one of the most common tumors worldwide, and cisplatin is a standard chemotherapeutic reagent for GC treatment. However, chemoresistance is an inherent challenge which limits its application and effectiveness in clinic. This study aims to investigate the mechanism of metformin-induced cisplatin resistance in GC. Intriguingly, the upregulation of mitophagy markers, mitochondrial fission, autophagy and mitophagosome were observed in SGC-7901/DDP cells compared to those in the SGC-7901 cells. Treatment with metformin significantly increased mitochondrial fission and mitophagy in both AGS and SGC-7901 cells, resulting in decreased ATP production, which unexpectedly protected GC cells against the cytotoxicity of cisplatin. In contrast, application of Chloroquine and 3-methyladenine, two inhibitors of autophagy, significantly alleviated the protective effect of metformin on SGC-7901 and AGS cells against cytotoxicity of cisplatin. Moreover, metformin also stimulated the phosphorylation of AMPK (Thr172) and increased the expression of mitophagy markers including Parkin and PINK1 in the AMPK signaling-dependent manner. Consistently, the cell viability and cell apoptosis assay showed that metformin-induced cisplatin resistance was prevented by knockdown of AMPKα1. Taken together, all data in this study indicate that metformin induced AMPK activation and PINK1/Parkin dependent mitophagy, which may contribute to the progression of cisplatin resistance in GC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Xiao, Xiao, Wang, Wang, Qu, Jiang, Tou, Chen and Han.)