MIL-53(Al)-oil/water emulsion composite as an adjuvant promotes immune responses to an inactivated pseudorabies virus vaccine in mice and pigs.

Although vaccination with inactivated vaccines is a popular preventive method against pseudorabies virus (PRV) infection, inactivated vaccines have poor protection efficiency because of their weak immunogenicity. The development of an effective adjuvant is urgently needed to improve the efficacy of inactivated PRV vaccines. In this study, a promising nanocomposite adjuvant named as MIL@A-SW01-C was developed by combining polyacrylic acid-coated metal-organic framework MIL-53(Al) (MIL@A) and squalene (oil)-in-water emulsion (SW01) and then mixing it with a carbomer solution. One part of the MIL@A was loaded onto the oil/water interface of SW01 emulsion via hydrophobic interaction and coordination, while another part was dispersed in the continuous water phase using carbomer. MIL@A-SW01-C showed good biocompatibility, high PRV (antigen)-loading capability, and sustained antigen release. Furthermore, the MIL@A-SW01-C adjuvanted PRV vaccine induced high specific serum antibody titers, increased splenocyte proliferation and cytokine secretion, and a more balanced Th1/Th2 immune response compared with commercial adjuvants, such as alum and biphasic 201. In the mouse challenge experiment, two- and one-shot vaccinations resulted in survival rates of 73.3% and 86.7%, respectively. After one-shot vaccination, the host animal pigs were also challenged with wild PRV. A protection rate of 100% was achieved, which was much higher than that observed with commercial adjuvants. This study not only establishes the superiority of MIL@A-SW01-C composite nanoadjuvant for inactivated PRV vaccine in mice and pigs but also presents an effective method for developing promising nanoadjuvants. STATEMENT OF SIGNIFICANCE: We have developed a nanocomposite of MIL-53(Al) and oil-in-water emulsion (MIL@A-SW01-C) as a promising adjuvant for the inactivated PRV vaccines. MIL@A-SW01-C has good biocompatibility, high PRV (antigen) loading capability, and a good property of sustained antigen release. The developed nanoadjuvant induced much higher specific IgG antibody titers, increased splenocyte proliferation and cytokine secretion, and a more balanced Th1/Th2 immune response than commercial adjuvants alum and biphasic 201. In challenge experiments with mice, survival rates of 73.3% and 86.7% were achieved from two-shot vaccination and one-shot vaccination, respectively. At the same time, a protection rate of 100% was achieved with the host animal pigs challenged with wild PRV.

Inhibitory effect of napabucasin on arbidol metabolism and its mechanism research.

As a broad-spectrum antiviral, and especially as a popular drug for treating coronavirus disease 2019 (COVID-19) today, arbidol often involves drug-drug interactions (DDI) when treating critical patients. This study established a rapid and effective ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to detect arbidol and its metabolite arbidol sulfoxide (M6-1) levels in vivo and in vitro. In this study, a 200 µL incubation system was used to study the inhibitory effect of the antitumor drug napabucasin on arbidol in vitro, with IC50 values of 2.25, 3.91, and 67.79 µM in rat liver microsomes (RLMs), human liver microsomes (HLMs), and CYP3A4.1, respectively. In addition, we found that the mechanism of inhibition was non-competitive inhibition in RLM and mixed inhibition in HLM. In pharmacokinetic experiments, it was observed that after gavage administration of 48 mg/kg napabucasin and 20 mg/kg arbidol, napabucasin inhibited the metabolism of arbidol in vivo and significantly changed the pharmacokinetic parameters of arbidol, such as AUC(0-t) and AUC(0-∞), in rats. We also found that napabucasin increased the AUC(0-t) and AUC(0-∞) of M6-1, the main metabolite of arbidol. This study provides a reference for the combined use of napabucasin and arbidol in clinical practice.

Toxic effect of chronic exposure to polyethylene nano/microplastics on oxidative stress, neurotoxicity and gut microbiota of adult zebrafish (Danio rerio).

The rapid development of aquaculture industry has provided a large amount of high-quality animal protein, while the food safety caused by microplastics and nanoplastics (MP/NPs) has become a major concern. In addition, recent evidence has shown the potential toxic effect of PE-MP/NPs, highlighting the need for further research into their environmental and health impacts. Chronic exposure of polyethylene microplastics (PE-MPs) and nanoplastics (PE-NPs) on adult zebrafish were conducted in the present study for 21 d. Organ-dependent oxidative damage induced by MP/NPs was observed. Insignificant differences in neurotoxicity and dysbiosis of gut microbiota were found between MPs and NPs. Changes in glutathione S-transferase (GST), glutathione (GSH), catalase (CAT), lipid peroxidation (LPO), and superoxide dismutase (SOD) showed that MP/NPs induced oxidative damage in gill and intestinal cells of zebrafish. The inhibited AChE activity suggested the potential neurotoxicity of microplastics and nanoplastics (MP/NPs). In addition, chronic exposure increased the alpha-diversity of intestinal microbiota. At the phylum level, the average relative abundance of Proteobacteria increased from 29.73% (control group) to 66.10% (microplastics), 54.84% (nanoplastics) and 60.03% (combined exposure), respectively. Tenericutes decreased from 55.43% (control group) to 20.02% (microplastics), 22.44% (nanoplastics) and 31.77% (combined exposure), respectively. Overall, this study provides new insights and objective evidence for the toxicity assessment of PE-MPs.

Thermo-Sensitive Microgel/Poly(ether sulfone) Composited Ultrafiltration Membranes.

Thermo-sensitive microgels known as PMO-MGs were synthesized via surfactant free emulsion polymerization, with poly(ethylene glycol) methacrylate (OEGMA475) and 2-(2-methoxyethoxy) ethyl methacrylate (MEO2MA) used as the monomers and N, N-methylene-bis-acrylamide used as the crosslinker. PMO-MGs are spherical in shape and have an average diameter of 323 ± 12 nm, as determined via transmission electron microscopy. PMO-MGs/poly (ether sulfone) (PES) composited ultrafiltration membranes were then successfully prepared via the non-solvent-induced phase separation (NIPS) method using a PMO-MG and PES mixed solution as the casting solution. The obtained membranes were systematically characterized via combined X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy and contact angle goniometer techniques. It was found that the presence of PMO-MGs significantly improved the surface hydrophilicity and antifouling performance of the obtained membranes and the PMO-MGs mainly located on the channel surface of the membranes. At 20 °C, the pure water flux increased from 217.6 L·m-2·h-1 for pure PES membrane (M00) to 369.7 L·m-2·h-1 for PMO-MGs/PES composited membrane (M20) fabricated using the casting solution with 20-weight by percentage microgels. The incorporation of PMO-MGs also gave the composited membranes a thermo-sensitive character. When the temperature increased from 20 to 45 °C, the pure water flux of M20 membrane was enhanced from 369.7 to 618.7 L·m-2·h-1.

Studies on the inhibitory effect of isavuconazole on flumatinib metabolism in vitro and in vivo.

As the validated agent for the treatment of chronic myelogenous leukemia (CML), flumatinib is a novel oral tyrosine kinase inhibitor (TKI) with higher potency and selectivity for BCR-ABL1 kinase compared to imatinib. Many patients experience aspergillosis infection and they may start using isavuconazole, which is an inhibitor of CYP3A4. However, there is no study on their interaction in vitro and in vivo. In the present study, the concentrations of flumatinib and its major metabolite M1 were rapidly determined using an stable ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The half-maximal inhibitory concentration (IC50) was 6.66 µM in human liver microsomes (HLM), while 0.62 µM in rat liver microsomes (RLM) and 2.90 µM in recombinant human CYP3A4 (rCYP3A4). Furthermore, the mechanisms of inhibition of flumatinib in human liver microsomes, rat liver microsomes and rCYP3A4 by isavuconazole were mixed. Moreover, ketoconazole, posaconazole, and isavuconazole showed more potent inhibitory effects than itraconazole, fluconazole, and voriconazole on HLM-mediated flumatinib metabolism. In pharmacokinetic experiments of rats, it was observed that isavuconazole could greatly change the pharmacokinetic parameters of flumatinib, including AUC(0-t), AUC(0-∞), Cmax and CLz/F, but had no effect on the metabolism of M1. According to the results of in vitro and in vivo studies, the metabolism of flumatinib was inhibited by isavuconazole, suggesting that isavuconazole may raise the plasma concentration of flumatinib. Thus, it is important to take special care of the interactions between flumatinib and isavuconazole in clinical applications.

Pharmacokinetics, bioavailability, and excretion of ponazuril in piglets.

Ponazuril is a triazine anticoccidial drug which is the main metabolite of toltrazuril in animals, it has excellent activity against many protozoa, including Cystoisospora suis, and has broad application prospects in the control of swine coccidiosis. To evaluate the pharmacokinetic and excretion characteristics of ponazuril, 12 healthy piglets aged 10-14 days were divided into 2 groups for pharmacokinetic studies, which were given 20 mg/kg body weight ponazuril orally and intravenously, respectively. And 6 other piglets were housed individually in metabolic cages and given the same oral dose of ponazuril. After administration, the concentration of ponazuril in plasma, fecal, and urine samples collected was determined using high-performance liquid chromatography (HPLC). The plasma concentration profiles of ponazuril obtained after intravenous and oral administration were analyzed simultaneously by the nonlinear mixed-effects (NLME) model. Following the results, the pharmacokinetics of ponazuril exhibited a Michaelis-Menten elimination with Michaelis-Menten constant Km and maximum metabolic rate Vm of 10.8 µg/mL and 0.083 mg/kg/h. The apparent volume of distribution was calculated to be 735 mL/kg, and the final estimated oral bioavailability was 81%. Besides, cumulatively 86.42 ± 2.96% of ponazuril was recovered from feces and 0.31% ± 0.08% from urine during 0-1,020 h after oral administration. These findings indicated a good oral absorption of ponazuril in piglets with nonlinear disposition and slow excretion largely via feces, implying sustained drug concentration in vivo and long-lasting anticoccidial effects.

Increased systemic RNA oxidative damage and diagnostic value of RNA oxidative metabolites during Shigella flexneri-induced intestinal infection.

BACKGROUND: Shigella flexneri (S. flexneri) is a major pathogen causing acute intestinal infection, but the systematic oxidative damage incurred during the course of infection has not been investigated. AIM: To investigate the incurred systemic RNA oxidative damage and the diagnostic value of RNA oxidative metabolites during S. flexneri-induced intestinal infection. METHODS: In this study, a Sprague-Dawley rat model of acute intestinal infection was established by oral gavage with S. flexneri strains. The changes in white blood cells (WBCs) and cytokine levels in blood and the inflammatory response in the colon were investigated. We also detected the RNA and DNA oxidation in urine and tissues. RESULTS: S. flexneri infection induced an increase in WBCs, C-reactive protein, interleukin (IL)-6, IL-10, IL-1ß, IL-4, IL-17a, IL-10, and tumor necrosis factor α (TNF-α) in blood. Of note, a significant increase in urinary 8-oxo-7,8-dihydroguanosine (8-oxo-Gsn), an important marker of total RNA oxidation, was detected after intestinal infection (P = 0.03). The urinary 8-oxo-Gsn level returned to the baseline level after recovery from infection. In addition, the results of a correlation analysis showed that urinary 8-oxo-Gsn was positively correlated with the WBC count and the cytokines IL-6, TNF-α, IL-10, IL-1ß, and IL-17α. Further detection of the oxidation in different tissues showed that S. flexneri infection induced RNA oxidative damage in the colon, ileum, liver, spleen, and brain. CONCLUSION: Acute infection induced by S. flexneri causes increased RNA oxidative damage in various tissues (liver, spleen, and brain) and an increase of 8-oxo-Gsn, a urinary metabolite. Urinary 8-oxo-Gsn may be useful as a biomarker for evaluating the severity and prognosis of infection.

Electroenzymatic glutamate sensing at near the theoretical performance limit.

The sensitivity and response time of glutamate sensors based on glutamate oxidase immobilized on planar platinum microelectrodes have been improved to near the theoretical performance limits predicted by a detailed mathematical model. Microprobes with an array of electroenzymatic sensing sites have emerged as useful tools for the monitoring of glutamate and other neurotransmitters in vivo; and implemented as such, they can be used to study many complex neurological diseases and disorders including Parkinson's disease and drug addiction. However, less than optimal sensitivity and response time has limited the spatiotemporal resolution of these promising research tools. A mathematical model has guided systematic improvement of an electroenzymatic glutamate microsensor constructed with a 1-2 µm-thick crosslinked glutamate oxidase layer and underlying permselective coating of polyphenylenediamine and Nafion reduced to less than 200 nm thick. These design modifications led to a nearly 6-fold improvement in sensitivity to 320 ± 20 nA µM-1 cm-2 at 37 °C and a ∼10-fold reduction in response time to 80 ± 10 ms. Importantly, the sensitivity and response times were attained while maintaining a low detection limit and excellent selectivity. Direct measurement of the transport properties of the enzyme and polymer layers used to create the biosensors enabled improvement of the mathematical model as well. Subsequent model simulations indicated that the performance characteristics achieved with the optimized biosensors approach the theoretical limits predicted for devices of this construction. Such high-performance glutamate biosensors will be more effective in vivo at a size closer to cellular dimension and will enable better correlation of glutamate signaling events with electrical recordings.

Degradable and Thermosensitive Microgels with Tannic Acid as the Sole Cross-Linker.

Poly(N-isopropylacrylamide) (PNIPAM)-tannic acid (TA) microgels were successfully prepared via surfactant-free emulsion polymerization (SFEP) at 70 °C in aqueous solution using N-isopropylacrylamide (NIPAM) as the monomer and a natural polyphenol macromolecule, TA, as the sole cross-linker. The cross-linking network of the PNIPAM-TA microgels was confirmed to contain both physical cross-linking structures formed via hydrogen-bonding interactions between TA and PNIPAM chains and chemical cross-linking structures formed via capturing the radicals of propagating polymer chains by catechol and pyrogallol groups of TA. Furthermore, TA was applied to modify the surface of hydrophobic Fe3O4 nanoparticles, leading to hydrophilic Fe3O4@TA composite nanoparticles, which were successfully used as the cross-linker to fabricate PNIPAM-Fe3O4@TA organic-inorganic hybrid microgels. The obtained PNIPAM-TA and PNIPAM-Fe3O4@TA organic-inorganic hybrid microgels had a uniform spherical shape with a relatively narrow size distribution and exhibited thermosensitive behavior and pH-tunable degradation. The PNIPAM-TA microgels were stable in the pH range of 1.3-11.1 but underwent complete degradation with pH above 11.4. The PNIPAM-Fe3O4@TA hybrid microgels were partially degraded at pH values of 1.3 and 2.1, stable in the pH range of 3.1-11.1, and underwent complete degradation at pH above 11.4. The partial degradation of PNIPAM-Fe3O4@TA organic-inorganic hybrid microgels under strong acidic conditions was attributed to the disintegration of Fe3O4 nanoparticles. The complete degradation of both microgels at pH above 11.4 was attributed to the hydrolysis of ester groups of TA under strong alkali conditions.

Novel Engineered Microgels with Amphipathic Network Structures for Simultaneous Tumor and Inflammation Depression.

Novel engineered microgels with amphipathic network structures were designed and synthesized by copolymerizing N-isopropylacrylamide, 1-vinylimidazole, and 2-(cinnamoyloxy)ethyl methacrylate in the presence of 1,6-dibromohexane. The engineered microgels possess hydrophilic quaternization cross-linking structures and hydrophobic cross-linking inner nanodomains, which are suitable for loading and simultaneous release of hydrophilic nonsteroidal anti-inflammatory drug diclofenac sodium (DS) and hydrophobic antic cancer drug doxorubicin (DOX), respectively. The engineered microgels exhibited excellent stability, low cytotoxicity, and long blood circulation time and could be uptaken into the cytoplasm of cells, metabolized, and excreted from the living body by the kidney and the liver. In vivo experiments showed that with injection of DS and DOX dual-drug-loaded microgels, simultaneous antitumor treatment and inflammation depression were achieved along with high antitumor efficacy and low drug-related toxicity. Such microgels with amphipathic network structures have promising applications for combination therapy.

Effect of oxycodone patient-controlled intravenous analgesia after cesarean section: a randomized controlled study.

BACKGROUND: Oxycodone is a semisynthetic µ-opioid receptor agonist with a potentially good analgesic efficacy in visceral pain. This study aims to compare the efficacy of oxycodone with sufentanil patient-controlled intravenous analgesia (PCIA). METHODS: One hundred and twenty primiparas undergoing elective cesarean section were randomized into four groups by different drugs of PCIA: group S (sufentanil 100 µg), group OS1 (sufentanil 70 µg, oxycodone 30 mg), group OS2 (sufentanil 50 µg, oxycodone 50 mg), and group O (oxycodone 100 mg). Ramosetron 0.3 mg was added to each group. In all groups, drugs were diluted to 100 mL and managed with a continuous infusion of 1 mL·h-1, a bolus dose of 2 mL, and a lockout interval of 15 min. The maximum dose of PCIA per hour was 10 mL. After surgery, pain scores, PCIA doses, and side effects were compared among groups. RESULTS: At all time points (6, 12, and 24 h after surgery), Numerical Rating Scale (NRS) of uterine cramping pain (NRS-U) scores in group O were lower than those in groups OS1 and S (P<0.008) and NRS-U scores in groups OS2 and OS1 were lower than that in group S (P<0.008). NRS of moving into the sitting position (NRS-S) scores in group O were lower than those in the other groups (P<0.008). NRS-S scores in group OS2 were lower than those in groups OS1 and S (P<0.008). At 12 and 24 h after surgery, NRS of incision pain at rest (NRS-R) scores in group O were lower than those in the other groups (P<0.008). At all time points, NRS-R scores in group OS2 were lower than those in groups OS1 and S (P<0.008). The number of PCIA boluses and amount of opioid consumption in group O were lower than those in groups OS1 and S at all time points (P<0.008). CONCLUSION: Oxycodone PCIA may be more effective than sufentanil PCIA for pain relief after cesarean section but the incidence of side effects needs further investigation.

Willed-movement training reduces brain damage and enhances synaptic plasticity related proteins synthesis after focal ischemia.

It has been wildly accepted that willed movement(WM) training promotes neurological rehabilitation in patients with stroke. However, it was not clear whether the effect of WM is better than other forms of exercise. The purpose of this study is to assess different effects of WM and other forms of exercise on rats with focal ischemia. The subjects are all had right middle cerebral artery occlusion (MCAO) surgery and randomly allocated to three groups of training and one control group with no training. Infarct volume by 2,3,5-triphenyltetrazolium chloride (TTC) dye, expression of PICK1 and synaptophysin in cerebral cortex and striatum of injured side by western blotting and immunofluorescence performed are analyzed. Exercise has done respectively on rats in each group for 15 days and 30 days. Compared with the control group, the brain damage is reduced in other groups after 15 days exercise. The protein expressions levels of synaptophysin and PICK1 are upregulated after exercise. Concentration of PICK1 protein in WM is greater than other exercise groups, and the expression of synaptophysin in WM and SM groups are higher than EM groups. The number of PICK1 positive cells, synaptophysin and PICK1 co-positive cells are increased by exercise. Synaptophysin is widely distributed in cortex surrounding the injury area in WM and EM. It is indicated in our result that willed-movement training is the most effective intervention in enhancing the PICK1-mediated synaptic plasticity in the area adjacent to the damage region of ischemic rats.

Poly(N-vinylpyrrolidinone) microgels: preparation, biocompatibility, and potential application as drug carriers.

The biocompatible poly(N-vinylpyrrolidinone) (PNVP) microgels were synthesized via surfactant free emulsion polymerization with N-vinylpyrrolidinone (NVP) as the monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker at 60 °C. The obtained PNVP microgels are spherical in shape with hydrodynamic diameter of approximately 200 nm and narrow size distribution. The PNVP microgels show rough surfaces due to the different reaction rates of monomer NVP and cross-linker EGDMA. The obtained PNVP microgels could well disperse in phosphate-buffered saline (PBS) solution with long-term stability, which make them candidates for bioapplications. The results of 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) tests indicated that the PNVP microgels are biocompatible with low toxicity even at a concentration of 1000 µg/mL. By labeling the PNVP microgels with fluorescein comonomer, it was demonstrated that the PNVP microgels could be uptaken by human embryonic kidney 293 (HEK-293) cells. The experimental results indicated that the release of isoniazid (INH, the hydrophilic model drug) could be well described by a Fickian release, whereas the microgels exhibited burst release for 5-fluorouracil (5-fu, the hydrophobic model drug).

Bis(µ-2,4-dihy-droxy-benzoato-κO:O')bis-[aqua-(2,4-dihy-droxy-benzoato-κO)(1,10-phenanthroline-κN,N')cadmium(II)].

In the title centrosymmetric dimeric Cd(II) complex, [Cd(2)(C(7)H(5)O(4))(4)(C(12)H(8)N(2))(2)(H(2)O)(2)], the Cd(II) cation is coord-inated by a bidentate phenanthroline (phen) ligand, three dihy-droxy-benzoate (dhba) anions and one water mol-ecule in a distorted CdN(2)O(4) octa-hedral geometry. Among the dhba anions, two anions bridge two Cd(II) cations to form the dimeric complex with significant different Cd-O bond distances of 2.2215 (19) and 2.406 (2) Å. The centroid-centroid distance of 3.4615 (19) Šbetween two nearly parallel benzene rings of the dhba and phen ligands coordinating to the same Cd(II) cation indicates the existence of intra-molecular π-π stacking in the complex. Extensive O-H⋯O hydrogen bonding and inter-molecular weak C-H⋯O hydrogen bonding help to stabilize the crystal structure. One hy-droxy group of the monodentate dhba ligand is disordered over two sites with a site-occupancy ratio of 0.9:0.1.

Poly[octa-µ-aqua-tetra-aqua-bis(µ(4)-5-sulfonatobenzene-1,3-dicarboxyl-ato)nickel(II)tetra-sodium].

In the crystal structure of the title compound, [Na(4)Ni(C(8)H(3)O(7)S)(2)(H(2)O)(12)](n), the Ni(II) cation occupies an inversion centre and is coordinated by the carboxyl groups of the sulfoisophthalate trianions and water mol-ecules in a distorted octa-hedral geometry. Two independent Na(I) atoms are connected by the carboxyl and sulfonate groups of the sulfoisophthalate ligands anions and water mol-ecules in a distorted octa-hedral geometry. The sulfoisophthalate ligands and coordinated water mol-ecules bridge the Ni(II) and Na(I) cations, forming a three-dimensional polymeric structure. Weak π-π stacking is present between parallel benzene rings [centroid-centroid distance = 3.9349 (10) Å]. Extensive O-H⋯O and C-H⋯O hydrogen bonding helps to stabilize the crystal structure.

Bis(1H-imidazole-κN)bis-(2-oxidopyridinium-3-carboxyl-ato-κO,O)nickel(II).

In the crystal structure of the title Ni(II) complex, [Ni(C(6)H(4)NO(3))(2)(C(3)H(4)N(2))(2)], the Ni(II) atom is located on a twofold rotation axis and is chelated by two oxidopyridiniumcarboxyl-ate anions and further cis-coordinated by two imidazole ligands in a distorted cis-N(2)O(4) octa-hedral geometry. The C-O bond distance of 1.2573 (19) Šfound for the non-coordinating O atom of the carboxyl-ate group indicates significant delocalization of π-electron density over this residue. Similarly, the C-O bond distance of 1.260 (2) Šin the heteroaromatic ring indicates delocalization between the deprotonated hydr-oxy group and the pyridinium ring. The uncoordinated carboxyl-ate O atom links with the imidazole and pyridinium rings of adjacent mol-ecules via N-H⋯O and C-H⋯O hydrogen bonding, leading to a two-dimensional array parallel to (100).

Bis(µ-3-hydroxy-benzoato)-κO:O;κO:O-bis-[bis-(1H-benzimidazole-κN)(3-hydroxy-benzoato-κO)nickel(II)] bis-(1H-benzimidazole-κN)bis-(3-hy-droxy-benzoato-κO)nickel(II) hexa-hydrate.

The title compound, [Ni(2)(C(7)H(5)O(3))(4)(C(7)H(6)N(2))(4)][Ni(C(7)H(5)O(3))(2)(C(7)H(6)N(2))(2)]·6H(2)O, is a mononuclear/dinuclear nickel(II) cocrystal, the two mol-ecular species inter-acting through hydrogen bonds that involve the uncoordinated water mol-ecules. In the mononuclear species, the Ni(II) ion, located on an inversion center, is coordinated by two 1H-benzimidazole (bzim) ligands and two 3-hydroxy-benzoate (hba) anions in a square-planar geometry. In the centrosymmetric dinuclear species, the Ni(II) ion is coordinated by two bzim ligands and three hba anions in a square-pyramidal geometry; of the two independent hba anions, one bridges two Ni(II) ions with both carboxylate and hydroxyl groups whereas the other coordin-ates in a unidentate manner to the Ni(II) ion. The apical Ni-O(hydrox-yl) bond is 0.39 Šlonger than the basal Ni-O(carbox-yl) bonds. The face-to-face separation of 3.326 (9) Šindicates the existence of π-π stacking between parallel bzim ligands of adjacent dinuclear entities. Extensive N-H⋯O and O-H⋯O hydrogen bonds help to stabilize the crystal structure.

Hexakis(1H-imidazole-κN)nickel(II) triaqua-tris(1H-imidazole-κN)nickel(II) bis-(naphthalene-1,4-dicarboxyl-ate).

The crystal structure of the title compound, [Ni(C(3)H(4)N(2))(6)][Ni(C(3)H(4)N(2))(3)(H(2)O)(3)](C(12)H(6)O(4))(2), contains uncoordinated naphthalene-dicarboxyl-ate dianions and two kinds of Ni(II) complex cations, both assuming distorted octa-hedral geometries. One Ni(II) ion is located on an inversion center and is coordinated by six imidazole mol-ecules, while the other Ni(II) ion is located on a twofold rotation axis and is coordinated by three water mol-ecules and three imidazole mol-ecules in a mer-NiN(3)O(3) arrangement. The naphthalene-dicarboxyl-ate dianion links both Ni(II) complex cations via O-H⋯O and N-H⋯O hydrogen bonding, but no π-π stacking is observed between aromatic rings in the crystal structure. One imidazole ligand is equally disordered over two sites about a twofold rotation axis; one N atom and one water O atom have site symmetry 2.

Tetra-aqua-bis(pyridine-3-sulfonato-κN)nickel(II).

In the mol-ecule of the title compound, [Ni(C(5)H(4)NO(3)S)(2)(H(2)O)(4)], the Ni(II) cation is located on an inversion center and is coordinated by four water mol-ecules and two pyridine-3-sulfonate anions with an NiN(2)O(4) distorted octa-hedral geometry. The face-to-face separation of 3.561 (5) Šbetween parallel pyridine rings indicates the existence of weak π-π stacking between the pyridine rings. The structure also contains inter-molecular O-H⋯O hydrogen bonding and weak C-H⋯O hydrogen bonding.

Bis(2,5-dihydroxy-benzoato-κO)bis-(1,10-phenathroline-κN,N')cadmium(II) 1.25-hydrate.

In the crystal structure of the title compound, [Cd(C(7)H(5)O(4))(2)(C(12)H(8)N(2))(2)]·1.25H(2)O, the Cd(2+) cation is coordinated by two phenanthroline (phen) mol-ecules and two 2,5-dihydroxy-benzoate (dhba) anions in a distorted octa-hedral geometry. The centroid-centroid distances of 3.809 (2) and 3.680 (2) Šbetween nearly parallel pyridine rings of the phen ligands and the benzene rings of dhba anions indicate that the dhba anions are involved in π-π stacking in the crystal structure. The face-to-face separation of 3.35 (3) Šbetween parallel phen ring systems also suggests π-π stacking between adjacent complex mol-ecules. The crystal structure contains extensive O-H⋯O and C-H⋯O hydrogen bonding.