Steerable Structural Evolvement and Adsorption Behavior of Metastable Polyoxovanadate-Based Metal-Organic Polyhedra.

Promoting the advancement of the structure and function of metastable substances is challenging but worthwhile. In particular, how to harness the entangled state and evolution path of labile porous structures has been at the forefront of research in molecular self-assembly. In this work, the metastable structures of polyoxovanadate-based metal-organic polyhedra (VMOPs) can be manually regulated, including separation of the interlocked aggregate by a ligand-widening approach as well as transformation from a tetrahedral to capsule-like scaffold via a vertice-remodeling strategy. In these processes, intra- and intermolecular π···π and C-H···π interactions have been recognized as the primary driving forces. Besides being responsible for commanding the structural evolvement of VMOPs, such weak interactions were able to program their spatial arrangements and hence the adsorption performances for dye and iodine. The successful use of such a weak force-dominated design concept beacons a feasible route for customization of the function-oriented metastable structures. Separation and transformation of the interlocked metastable VMOPs have been achieved via the respective ligand-widening approach and vertice-remodeling strategy. Not only their structures but also adsorption features could be well regulated by such a weak force-dominated design concept.

Space-Confined Nucleation of Semimetal-Oxo Clusters within a [H7P8W48O184]33- Macrocycle: Synthesis, Structure, and Enhanced Proton Conductivity.

Spatially confined assembly of semimetallic oxyanions (AsO33- and SbO33-) within a [H7P8W48O184]33- (P8W48) macrocycle has afforded three nanoscale polyanions, [{AsIII5O4(OH)3}2(P8W48O184)]32- (As10), [(SbIIIOH)4(P8W48O184)]32- (Sb4), and [(SbIIIOH)8(P8W48O184)]24- (Sb8), which were crystallized as the hydrated mixed-cation salts (Me2NH2)13K7Na2Li10[{AsIII5O4(OH)3}2(P8W48O184)]·32H2O (DMA-KNaLi-As10), K20Li12[(SbIIIOH)4(P8W48O184)]·52H2O (KLi-Sb4), and (Me2NH2)8K6Na5Li5[(SbIIIOH)8(P8W48O184)]·65H2O (DMA-KNaLi-Sb8), respectively. A multitude of solid- and solution-state physicochemical techniques were employed to systematically characterize the structure and composition of the as-made compounds. The polyanion of As10 represents the first example of a semimetal-oxo cluster-substituted P8W48 and accommodates the largest AsIII-oxo cluster in polyoxometalates (POMs) reported to date. The number of incorporated SbO33- groups in Sb4 and Sb8 could be customized by a simple variation of SbIII-containing precursors. Encapsulation of semimetallic oxyanions inside P8W48 sets out a valid strategy not only for the development of host-guest assemblies in POM chemistry but also for their function expansion in emerging applications such as proton-conducting materials, for which DMA-KNaLi-As10 showcases an outstanding conductivity of 1.2 × 10-2 S cm-1 at 85 °C and 70% RH.

Host-Guest Chemistry in Discrete Polyoxo-12-Palladate(II) Cubes [MO8Pd12L8]n- (M = ScIII, CoII, CuII, L = AsO43 -; M = CdII, HgII, L = PhAsO32-): Structure, Magnetism, and Catalytic Hydrogenation.

A family of five host-guest assemblies comprising different metal ions inside a cuboid 12-palladium-oxo cage, [MO8Pd12L8]n- (MPd12L8, M = ScIII, CoII, CuII, L = AsO43-; M = CdII, HgII, L = PhAsO32-), was synthesized and structurally characterized in the solid state by single-crystal X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis, and their solution and gas-phase stability were validated by multinuclear NMR spectroscopy and electrospray-ionization mass spectrometry (ESI-MS). The polyoxopalladates (POPs) ScPd12As8, CoPd12As8, and CuPd12As8 represent the first three examples of the MPd12As8 archetype. The unique cubic ligand field of {MO8} allows for collecting the speciation profiles of the POPs in solution using 45Sc and 113Cd NMR techniques. Detailed magnetic and electron paramagnetic resonance (EPR) studies were performed on CuPd12As8. Catalytic studies on MPd12As8 (M = CuII and CoII) supported on SBA-15 unveiled a guest metal-dependent structure-function relationship, with CuPd12As8 being the more efficient precatalyst for the hydroconversion of o-xylene in a fixed-bed reactor.

Lewis Acid Guests in a {P8 W48 } Archetypal Polyoxotungstate Host: Enhanced Proton Conductivity via Metal-Oxo Cluster within Cluster Assemblies.

Complexes made by hosts that completely surround their guests provide a means to stabilize reactive chemical intermediates, transfer biologically active cargo to a diseased cell, and construct molecular-scale devices. By the virtue of inorganic host-guest self-assembly, nucleation processes in the cavity of a {P8 W48 }-archetype phosphotungstate has afforded a nanoscale 16-AlIII -32-oxo cluster and its GaIII analogue that contain the largest number of AlIII /GaIII ions yet found in polyoxometalate (POM) chemistry. Interestingly, the rich Lewis acid AlIII centers within the Lewis base POM support shows an exceptional proton conductivity of 4.5×10-2  S cm-1 (85 °C, 70 % RH; RH: relative humidity), which is by far the highest conductivity reported among POM-based single-crystal proton conductors.

Making an inverted Keggin ion lacunary.

The century-old inverted Keggin ion has been revisited in an effort to unleash its potential in the structural engineering and functional development of polyoxomolybdates (POMos). Over the past hundred years, attempts to program the metal-oxo scaffold of inverted Keggins have been conducted continually but without any success. In this work, a structurally inert, inverted Keggin-type POMo could finally be altered by means of a binary heterogroup-templated approach, resulting in the successful isolation of two lacunary species. The local structure and charge distribution of these species are adjustable, and hence they serve as available building blocks for the subsequent controlled assembly of a CeIII-incorporated derivative. From the plenary to the lacunary, the enclosed structure of the inverted Keggin has been opened up significantly, resulting in less steric hindrance, along with a transition from an electron neutral species to a negatively charged species. Owing to these beneficial properties, the emerging defect-containing polyanions demonstrated outstanding Lewis acid-base catalytic activity in the high efficiency production of pyrazoles.

Binary Heterogroup-Templated Scaffolds of Polyoxopalladates as Precatalysts for Plasma-Assisted Ammonia Synthesis.

In addition to improving the synthetic efficiency, the template method can do a lot more in the chemistry of polyoxopalladates (POPs), such as the establishment of novel metal-oxo scaffolds. In this endeavor, a binary system comprising heterogroups of nonmetallic {As/SiO4} and metallic {VO4/5} successfully fulfills the templated growth of two POPs with unprecedented seesaw- and spindle-like prototypes. Of these, self-aggregation of heterogroups beacons an effective route to break the highly symmetrical PdII-oxo matrix and to force the arrangement of addenda in a nonconventional manner. Aside from the interest in their structural features, the as-made POPs are available for immobilization on the mesoporous SBA-15 as precatalysts for ammonia synthesis. The outer cover of heterogroups in the POP precursors contributes to the ultrafine size and uniform distribution of derived Pd0 nanoparticles (PdNPs). With the help of plasma activation on H2 and N2, such PdNPs-SBA15 catalysts significantly improve the production performance of NH3, showcasing the maximum synthesis rate of 64.42 µmol/(min·gcat) with the corresponding energy yield as high as 4.38 g-NH3/kWh.

3,3'-Diindolylmethane alleviates acute atopic dermatitis by regulating T cell differentiation in a mouse model.

Atopic dermatitis is a severe, chronic relapsing inflammatory disease of the skin with family clustering. It is characterized into acute phase, which is dominated by T helper 2-type immune responses, and chronic phase, which is dominated by T helper 1-type immune responses. Studies have shown that 3,3'-diindolylmethane not only has antitumor effects but also can relieve symptoms of inflammatory diseases by inhibiting the nuclear factor-κB signaling pathway and regulating T cell differentiation. To study the effect of 3,3'-diindolylmethane on atopic dermatitis and the underlying mechanism, a mouse model of acute atopic dermatitis was established using 2,4-dinitrofluorobenzene. After intraperitoneal injection of 3,3'-diindolylmethane, skin erythema and edema in mice were significantly alleviated. Furthermore, 3,3'-diindolylmethane reduced immune activation, probably by inhibiting the secretion of thymic stromal lymphopoietin by keratinocytes. 3,3'-Diindolylmethane also promoted the differentiation of regulatory T cells and inhibited the activation of T helper 2 and T helper 17 cells to reduce atopic dermatitis-related immune responses. However, it showed no significant effect on the differentiation of T helper 1 cells. These results indicate that 3,3'-diindolylmethane has a significant inhibitory effect on T helper 2 cells in the acute phase of atopic dermatitis. Our findings may provide not only more insights into the pathological mechanism of AD, but also a new candidate medicine for it.

Airway Management of Retrosternal Goiters in 22 Cases in a Tertiary Referral Center.

BACKGROUND: The present study aimed to investigate the incidence and extent of difficult airway management in patients with massive retrosternal goiter. DESIGN: An 8-year retrospective analysis was performed to identify patients who underwent massive retrosternal thyroidectomy. A total of 22 cases were identified as giant retrosternal goiter, followed by a review of each patient's preoperative computerized tomography imaging. INTERVENTIONS: There were no cases of failed intubation. Twenty patients underwent uneventful tracheal intubation using direct laryngoscopy or Glidescope. Thirteen patients received a muscle relaxant intravenously, and two patients were induced with sevoflurane. Five patients underwent awake tracheal intubation, including awake fiberoptic intubation in three patients. Before entering the operating theatre, the remaining two patients underwent oral tracheal intubation with Glidescope in the emergency department. RESULTS: Two patients had tracheal intubation before they entered the operating theatre. Once entering vocal cords, tracheal intubation can pass beyond the site of the tracheal obstruction without difficulty. One patient died because of serious perioperative bleeding owing to the adhesion between the retrosternal goiter and large vessel within the thoracic cavity. One patient experienced dyspnea after extubation and was intubated again. CONCLUSION: Intravenous induction of muscle relaxant using laryngoscopy or Glidescope is feasible in patients with massive benign retrosternal goiter. The incidence of difficult intubation and postoperative tracheomalacia is likely too rare. Furthermore, perioperative bleeding and postoperative airway complication seem frequent.

Wfs1 and Related Molecules as Key Candidate Genes in the Hippocampus of Depression.

BACKGROUND: Depression is a prevalent mental disorder, which is difficult to diagnose and treat due to its unclear pathogenic mechanisms. The discovery of novel and effective therapeutic targets for depression is urgently needed. The hippocampus is a crucial region involved in depression and has been a therapeutic target for many antidepressants. Thus, it is beneficial for comprehensive research to be carried out on the molecular mechanisms of the hippocampus involved in the pathogenesis of depression. This study aims to investigate the differentially expressed genes (DEG) in the hippocampus in a chronic unpredictable mild stress (CUMS) mouse model. METHOD: The study obtained GSE84183 from the GEO database. The R language screened the differential expression genes (DEG) in the hippocampus tissue of depressed mice, and the enrichment pathways of DEGs were analyzed. A protein-protein interaction (PPI) network was constructed in the STRING database and visualized in Cytoscape software. MicroRNAs for these DEGs were obtained from TarBase and mortar base databases, and transcription factors (TF) related to DEG were predicted from the ENCODE database. Both networks used the visual analysis platform NetworkAnalyst. Finally, the microRNA-TF network was integrated based on the above two networks and imported into Cytoscape for further analysis. RESULTS: This study screened 325 differentially expressed genes, containing 42 downregulated genes and 283 upregulated genes. Most of these genes are enriched in the cell cycle and the chemokine signaling pathway. Meanwhile, Wfs1, one of the top ten DEGs, was identified as the key regulator of the cell cycle and the participator in the highest number of modules screened out in PPI networks. Wfs1-related molecules, including UBTF, mmu-mir-17-5p, and mmu-mir-7b-5p, were therefore screened out. Furthermore, we confirmed the downregulation of Wfs1 and upregulation of UBTF/mmu-mir-17-5p/mmu-mir-7b-5p in the hippocampus of the CUMS mouse model. Our data indicate that Wfs1 and related molecules were predicted to be associated with the pathological process of depression. This research provided potential new molecular targets of stress-induced depression.

Silencing of spinal Trpv1 attenuates neuropathic pain in rats by inhibiting CAMKII expression and ERK2 phosphorylation.

Accumulating evidence suggests a potential role of transient receptor potential vanilloid 1 (TRPV1) channels in inflammatory and cancer-related pain. However, the role of TRPV1 in the maintenance of neuropathic pain remains elusive. The current study investigated the effects of transient Trpv1 gene silencing using a small interference RNA (siRNA) on neuropathic pain induced by chronic constriction injury (CCI) of the sciatic nerve in rats. Seven days after CCI, the TRPV1 siRNA was intrathecally administered (5 µg/15 µl, once daily for 2 days). TRPV1 and Ca2+/calmodulin-dependent protein kinase II (CAMKII) expression and extracellular signal-regulated kinase (ERK) phosphorylation in the spinal cord were detected using western blotting. The thresholds to mechanical and thermal stimuli were determined before and after intrathecal TRPV1 siRNA administration. TRPV1 and CAMKII expression and ERK2 phosphorylation in the spinal cord were upregulated after CCI. Intrathecal administration of the TRPV1 siRNA not only attenuated behavioural hyperalgesia but also reduced the expression of TRPV1 and CAMKII, as well as ERK2 phosphorylation. Based on these results, silencing of the TRPV1 gene in the spinal cord attenuates the maintenance of neuropathic pain by inhibiting CAMKII/ERK2 activation and suggests that TRPV1 represents a potential target in pain therapy.

Goal-directed fluid therapy does not reduce postoperative ileus in gastrointestinal surgery: A meta-analysis of randomized controlled trials.

BACKGROUND: Perioperative goal-directed fluid therapy (GDFT) aiming to maintain individual fluid balance based on sensitive parameters was prevalent in major surgery, especially in enhanced recovery after surgery (ERAS) pathway. This meta-analysis was conducted for the purpose of evaluating whether GDFT impacts on occurrence of postoperative ileus and whether its application is worthwhile in gastrointestinal surgery. METHODS: A systematic search of RCTs compared GDFT with other fluid management in patients undergoing gastrointestinal surgery from the PubMed, Web of Science, Embase, Cochrane Library databases was implemented. The primary outcome is incidence of postoperative ileus. Other outcome measures were length of hospital stay (LOS), postoperative morbidity and mortality. Subgroup analysis was planed a prior to verify the definite role of GDFT. RESULTS: 12 trials consisted of 1836 patients were included in the final analysis. GDFT did not influence the occurrence of postoperative ileus (relative risk, RR 0.71, 95% confidence interval, CI 0.47-1.07, P = .10), with moderate heterogeneity (I = 29%, P = .16). No difference was found between GDFT and control groups in LOS (mean difference -0.17 days, 95% CI -0.73 to 0.39, P = .55), total complication rate (RR 0.92, 95% CI 0.81-1.05, P = .23), and 30-day mortality (RR 0.91, 95% CI 0.47-1.75, P = .77). In other secondary outcomes, only wound infection rate was lower in the GDFT group (RR 0.68, 95% CI 0.50-0.93, P = .02). When performed subgroup analysis, GDFT was superior in reduction ileus only when compared with standard therapy or in those outside ERAS. CONCLUSIONS: It is possible that GDFT dose not affect the occurrence of postoperative ileus in gastrointestinal surgery. It scarcely influences postoperative morbidity and mortality as well. However, lower incidence of ileus is observed in GDFT group either outside ERAS or compared with standard fluid therapy. Probably, GDFT may not be necessary in the ERAS pathway or if a hybrid approach is adopted.

Dexmedetomidine Attenuates Neuropathic Pain by Inhibiting P2X7R Expression and ERK Phosphorylation in Rats.

α2-Adrenoceptor agonists attenuate hypersensitivity under neuropathic conditions. However, the mechanisms underlying this attenuation remain largely unknown. In the present study, we explored the potential roles of purinergic receptor 7 (P2X7R)/extracellular signal-regulated kinase (ERK) signaling in the anti-nociceptive effect of dexmedetomidine in a rat model of neuropathic pain induced by chronic constriction injury (CCI) of the sciatic nerve. An animal model of CCI was adopted to mimic the clinical neuropathic pain state. Behavioral hypersensitivity to mechanical and thermal stimuli was determined by von Frey filament and Hargreaves' tests, and the spinal P2X7R expression level and ERK phosphorylation were analyzed using western blot analysis and immunohistochemistry. In parallel with the development of mechanical and thermal hyperalgesia, a significant increase in P2X7R expression was noted in the ipsilateral spinal cord on day 7 after CCI. Intrathecal administration of dexmedetomidine (2.5 µg) for 3 days not only attenuated neuropathic pain but also inhibited the CCI-induced P2X7R upregulation and ERK phosphorylation. Intrathecal dexmedetomidine administration did not produce obvious effects on locomotor function. The present study demonstrated that dexmedetomidine attenuates the neuropathic pain induced by CCI of the sciatic nerve in rats by inhibiting spinal P2X7R expression and ERK phosphorylation, indicating the potential therapeutic implications of dexmedetomidine administration for the treatment of neuropathic pain.

The effect of epidural lidocaine administration on sedation of propofol general anesthesia: a randomized trial.

STUDY OBJECTIVE: To examine the influence of epidural and intravenous (IV) lidocaine, and height of the epidural sensory block, on the dose of propofol required for induction of general anesthesia. DESIGN: Randomized controlled study. SETTING: University hospital. PATIENTS: 66 adult, ASA physical status 1 and 2 patients, aged 25 to 65 years, undergoing elective abdominal surgery. INTERVENTIONS: Patients were randomized to 4 groups: the epidural saline control group (Group C; L2-L3 puncture, epidural and IV saline), the IV lidocaine group (Group IV; L2-L3 puncture, saline epidural, IV lidocaine 1 mg/kg), the lumbar epidural lidocaine group (Group EL; L2-L3 puncture, 1.5% lidocaine epidural, IV saline), and the thoracic epidural lidocaine group (Group ET; T9-T10 puncture, 1.5%lidocaine epidural, IV saline). Two minutes after the beginning of the infusion of IV lidocaine or saline, propofol anesthesia was initiated. MEASUREMENTS: Mean arterial blood pressure (MAP), heart rate (HR), and sensory block height were monitored. The induction dose of propofol, its estimated effect-site concentration (Ce), and plasma concentration were measured at various time points. Finally, we recorded the time taken for the bispectral index (BIS) to decrease to 60, the plasma concentration of lidocaine at induction, and the occurrence of adverse events. The induction time (when BIS reached 60) also was recorded. MAIN RESULTS: The induction propofol dose, Ce, and plasma concentration of propofol when BIS equaled 60 were significantly lower in Group IV, Group EL, and Group ET than Group C. The above parameters in Group ET (T9 - T10 puncture) were significantly less than in Group EL (L2 - L3 puncture). The induction doses of propofol and plasma concentration of propofol and lidocaine were significantly higher in Group IV than in Groups EL or ET. CONCLUSIONS: Epidural and IV lidocaine reduce the dose of propofol required to induce general anesthesia. Administration of lidocaine via the epidural route reduces anesthetic requirements more so than the IV route. Propofol requirements were further reduced in patients with higher sensory epidural block.

Epidural fentanyl decreases the minimum local analgesic concentration of epidural lidocaine.

BACKGROUND: Epidural lidocaine can be used when regional anesthesia needs to be established quickly, but the effect of co-administering epidural fentanyl on the minimum local analgesic concentration (MLAC) of lidocaine is not known. We compared the MLAC of epidural lidocaine in combination with different doses of fentanyl for epidural anesthesia in adults. METHODS: One hundred and twenty patients requiring epidural analgesia were randomly allocated to receive 20 ml of one of four solutions: lidocaine, or lidocaine plus fentanyl 1 µg/ml, 2 µg/ml, or 3 µg/ml. The first patient in each group was administered 1% lidocaine weight by volume; subsequent patients received a concentration determined by the response of the previous patient to a higher or lower concentration according to up and down sequential allocation in 0.1% increments. Efficacy was assessed using a visual analog pain scale, and accepted if this was = 10 mm on a 100 mm scale within 30 minutes. The extent of motor block and of nausea and vomiting were recorded at 30 minutes after administration of the epidural solution and two hours after surgery, respectively. RESULTS: The MLAC of lidocaine in those receiving lidocaine alone was 0.785% (95%CI 0.738 - 0.864). A significant dose-dependent reduction was observed with the addition of fentanyl: the MLAC of lidocaine with fentanyl at 2 µg/ml was 0.596% (95%CI 0.537 - 0.660) and 0.387% with fentanyl at 3 µg/ml (95%CI 0.329 - 0.446, P < 0.001). CONCLUSION: Epidural fentanyl significantly reduces the dose of lidocaine required for effective epidural analgesia in adults without causing adverse side effects.