AnimalMetaOmics: a multi-omics data resources for exploring animal microbial genomes and microbiomes.

The Animal Meta-omics landscape database (AnimalMetaOmics, https://yanglab.hzau.edu.cn/animalmetaomics#/) is a comprehensive and freely available resource that includes metagenomic, metatranscriptomic, and metaproteomic data from various non-human animal species and provides abundant information on animal microbiomes, including cluster analysis of microbial cognate genes, functional gene annotations, active microbiota composition, gene expression abundance, and microbial protein identification. In this work, 55 898 microbial genomes were annotated from 581 animal species, including 42 924 bacterial genomes, 12 336 virus genomes, 496 archaea genomes and 142 fungi genomes. Moreover, 321 metatranscriptomic datasets were analyzed from 31 animal species and 326 metaproteomic datasets from four animal species, as well as the pan-genomic dynamics and compositional characteristics of 679 bacterial species and 13 archaea species from animal hosts. Researchers can efficiently access and acquire the information of cross-host microbiota through a user-friendly interface, such as species, genomes, activity levels, expressed protein sequences and functions, and pan-genome composition. These valuable resources provide an important reference for better exploring the classification, functional diversity, biological process diversity and functional genes of animal microbiota.

CRAMdb: a comprehensive database for composition and roles of microbiome in animals.

CRAMdb (a database for composition and roles of animal microbiome) is a comprehensive resource of curated and consistently annotated metagenomes for non-human animals. It focuses on the composition and roles of the microbiome in various animal species. The main goal of the CRAMdb is to facilitate the reuse of animal metagenomic data, and enable cross-host and cross-phenotype comparisons. To this end, we consistently annotated microbiomes (including 16S, 18S, ITS and metagenomics sequencing data) of 516 animals from 475 projects spanning 43 phenotype pairs to construct the database that is equipped with 9430 bacteria, 278 archaea, 2216 fungi and 458 viruses. CRAMdb provides two main contents: microbiome composition data, illustrating the landscape of the microbiota (bacteria, archaea, fungi, and viruses) in various animal species, and microbiome association data, revealing the relationships between the microbiota and various phenotypes across different animal species. More importantly, users can quickly compare the composition of the microbiota of interest cross-host or body site and the associated taxa that differ between phenotype pairs cross-host or cross-phenotype. CRAMdb is freely available at (http://www.ehbio.com/CRAMdb).

Efficacy of Dexamethasone in Reducing Pain and Inflammation and Accelerating Total Hip Arthroplasty Postoperative Recovery: A Randomized Controlled Trial.

PURPOSE: To evaluate the efficacy of dexamethasone in reducing pain and accelerating recovery after total hip arthroplasty (THA). DESIGN: A prospective randomized controlled trial. METHODS: A total of 98 patients who underwent THA received either low-dose (10 mg) dexamethasone (dexa group) or isotonic saline (placebo group). C-reactive protein and interleukin-6 levels were recorded at 24, 48, and 72 hours after surgery. Pain visual analog scale (VAS) score at rest and walking, the incidence of postoperative nausea and vomiting (PONV), nausea VAS score, postoperative identity-consequence fatigue scale rating, antiemetic use, postoperative length of stay (PLOS), and complications were also recorded and compared. FINDINGS: Inflammatory marker (C-reactive protein and interleukin-6) levels at 24, 48, and 72 hours postoperatively in the dexa group were lower than that in the placebo group (P < .05). After 24 hours of rest, the dynamic pain VAS scores in the dexa group were lower than those in the placebo group (P < .05). The incidence of PONV, nausea VAS score, and identity-consequence fatigue scale score in the dexa group were lower than those in the placebo group (P < .05), and the dosages of analgesics and antiemetics were also lower (P < .05). In addition, PLOS in the dexa group was shorter than that in the placebo group (P < .05). No significant difference in perioperative complications between the two groups was observed (P > .05). CONCLUSIONS: Low-dose dexamethasone in the THA perioperative period can effectively reduce inflammatory marker levels, pain, nausea, postoperative fatigue, opioid analgesic use, and shorten PLOS without increasing complications.

Defect-engineered three-dimensional vanadium diselenide microflowers/nanosheets on carbon cloth by chemical vapor deposition for high-performance hydrogen evolution reaction.

In the past decades, defect engineering has become an effective strategy to significantly improve the hydrogen evolution reaction (HER) efficiency of electrocatalysts. In this work, a facile chemical vapor deposition (CVD) method is firstly adopted to demonstrate defect engineering in high-efficiency HER electrocatalysts of vanadium diselenide nanostructures. For practical applications, the conductive substrate of carbon cloth (CC) is selected as the growth substrate. By using a four-time CVD method, uniform three-dimensional microflowers with defect-rich small nanosheets on the surface are prepared directly on the CC substrate, displaying a stable HER performance with a low Tafel slope value of 125 mV dec-1and low overpotential voltage of 295 mV at a current density of 10 mA cm-2in alkaline electrolyte. Based on the results of x-ray photoelectron spectra and density functional theory calculations, the impressive HER performance originates from the Se vacancy-related active sites of small nanosheets, while the microflower/nanosheet homoepitaxy structure facilitates the carrier flow between the active sites and conductive substrate. All the results present a new route to achieve defect engineering using the facile CVD technique, and pave a novel way to prepare high-activity layered electrocatalysts directly on a conductive substrate.

R93P Substitution in the PmrB HAMP Domain Contributes to Colistin Heteroresistance in Escherichia coli Isolates from Swine.

Here, the mechanisms of colistin heteroresistance (CHR) were assessed in 12 Escherichia coli isolates from swine in China. CHR was investigated by population analysis profile tests. CHR stability was studied by culturing isolates for five overnight incubation periods in colistin-free medium. Subsequently, the mcr-1 gene and mutations in PmrAB, PhoPQ, and MgrB were screened in parental isolates and resistant subpopulations. Additionally, the expression levels of phoPQ, its target gene pagP, and its negative regulator gene mgrB, as well as pmrAB and its target genes pmrHFIJKLM and pmrC, were determined by real-time relative quantitative PCR. Eleven of the 12 isolates were confirmed to show CHR, with 17 resistant subpopulations. Also, 11 of the 17 subpopulations (64.71%) harbored point mutations in PmrB and/or PhoQ, differing from their parental isolates. However, only one stable resistant subpopulation (EPF42-4) was identified; it harbored an arginine-to-proline substitution at position 93 (R93P) within the PmrB HAMP (histidine kinase, adenylyl cyclase, methyl-binding protein, and phosphatase) domain. Compared to the pmrB expression levels in the parental isolate EPF42 and E. coli K-12 MG1655, remarkable pmrB overexpression was observed in EPF42-4, which showed upregulated pmrA, pmrK, and pmrC expression. Structural analysis demonstrated that the R93P substitution promotes conformational changes in the HAMP domain, leading to an acceleration in its signal transduction ability and the activation of PmrB expression. In conclusion, point mutations in PmrB and/or PhoQ were primarily associated with CHR. The R93P substitution resulted in the establishment of stable resistant subpopulations in E. coli showing CHR.

Formation and transformation of chloroform during managed aquifer recharge (MAR).

Chlorination is an effective method to protect the safety of groundwater systems during managed aquifer recharge. However, chlorination leads to the formation of disinfection by-products, whose behavior in aquifers remains unclear and has caused public concern. In this study, an in-site test was performed on an anoxic aquifer in Shouguang City, China, to investigate the formation and transformation of chloroform during managed aquifer recharge. The field tests showed that the formation of chloroform in groundwater caused by the recharge of chlorinated water, and that the fate of chloroform was affected by adsorption and biodegradation. The retardation factor was 1.27, and the half-life was 29 days. The formation and transformation of chloroform during continuous recharge under different hydrochemical conditions was further investigated by batch experiments. These experiments showed that the formation of chloroform increased with contact time, tended to be stable after 10 h, and was facilitated by high chloride/TOC ratios, high pH, and low ionic strength (IS) for a given contact time. The adsorption experiments showed that the process accords with the pseudo-second-order kinetic equations and the Freundlich model. The adsorption capacity was pH dependent (1.01-1.66 µg/g at pH 5 and 2.17-3.05 µg/g at pH 9). Increasing the IS promotes adsorption. The results from biodegradation experiments indicated that the biodegradation was well fitted by the Monod equation. The retardation factor in the batch experiments was close to that of the field test, but the half-life was less than the field test. This is mainly due to the difference in the concentration of dissolved oxygen.

Development of a multimetric index based on benthic macroinvertebrates for the assessment of urban stream health in Jinan City, China.

Assessment of the health of urban streams is an important theoretical and practical topic, which is related to the impacts of physiochemical processes, hydrological modifications, and the biological community. However, previous assessments of the urban water quality were predominantly conducted by measuring physical and chemical factors rather than biological monitoring. The purpose of this study was to develop an urban stream multimetric index (USMI) based on benthic macroinvertebrates to assess the health of aquatic ecosystem in Jinan City. Two hundred and eighty-eight samples were collected during two consecutive years (2014-2015) from 48 sites located within the city. Metrics related to the benthic macroinvertebrate richness, diversity, composition and abundance, and functional feeding groups were selected by using box-plots and the Kruskal-Wallis test. The final index derived from selected metrics was divided into five river quality classes (excellent, good, moderate, poor, and bad). A validation procedure using box-plots and the non-parametric Mann-Whitney U test showed that the USMI was useful to assess the health of urban streams.

Water-soluble biopolymers calcium polymalate derived from fermentation broth of Aureobasidium pullulans markedly alleviates osteoporosis and fatigue.

Osteoporosis is a prevalent condition characterized by bone loss and decreased skeletal strength, resulting in an elevated risk of fractures. Calcium plays a crucial role in preventing and managing osteoporosis. However, traditional calcium supplements have limited bioavailability, poor solubility, and adverse effects. In this study, we isolated a natural soluble biopolymer, calcium polymalate (PMACa), from the fermentation broth of the fungus Aureobasidium pullulans, to investigate its potential as an anti-osteoporosis therapeutic agent. Characterization revealed that linear PMA-Ca chains juxtaposed to form a porous, rod-like state, in the presence of Ca2+. In vivo mouse models demonstrated that PMA-Ca significantly promoted the conversion of serum calcium into bone calcium, and stimulated bone growth and osteogenesis. Additionally, PMA-Ca alleviated exercise fatigue in mice by facilitating the removal of essential metabolites, such as serum lactate (BLA) and blood urea nitrogen (BUN), from their bloodstream. In vitro studies further showed that PMA-Ca strengthened osteoblast cell activity, proliferation, and mineralization. And PMA-Ca upregulated the expression of some genes involved in osteoblast differentiation, indicating a potential correlation between bone formation and PMACa. These findings indicate that soluble PMA-Ca has the potential to be a novel biopolymer-based calcium supplement with sustainable production sourced from the fermentation industry.

WITHDRAWN: A preliminary assessment on spatial prioritization for integrated urban flood management based on source tracking method.

This article has been withdrawn at the request of the editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

Cyclic cryotherapy with vitamin D facilitates early rehabilitation after total knee arthroplasty.

Objective: This study aimed to evaluate the efficacy of cyclic cryotherapy and vitamin D administration on early rehabilitation after total knee arthroplasty (TKA), as its efficacy remains unclear. Methods: We divided 150 patients (three groups) who underwent TKA into those treated with or without cyclic cryotherapy and vitamin D. Results: Compared with patients who did not receive cyclic cryotherapy, those who received postoperative cyclic cryotherapy and vitamin D supplementation had significantly higher American Knee Society Scores (AKSS) on postoperative day (POD) 7 and at 1 month postoperatively; higher visual analogue scale (VAS) values on POD1-3 and POD7; reduced thigh swelling on POD3 and POD7; increased range of motion (ROM) on POD3, POD7, and at 1 month postoperatively; and reduced postoperative length of stay (PLOS). However, no significant difference in patient satisfaction was observed between the patient groups. At 1 and 3 months postoperatively, patients administered cyclic cryotherapy and vitamin D had significantly higher AKSS, ROM, and vitamin D levels than those who did not receive vitamin D. No perioperative complications such as surgical site infection, skin frostbite, or vitamin D intoxication were observed. Conclusion: Cyclic cryotherapy post-TKA had short-term advantages in terms of AKSS, VAS, thigh swelling, ROM, PLOS, and accelerated rehabilitation, but did not improve patient satisfaction. Cyclic cryotherapy combined with vitamin D improved AKSS and ROM at 1 and 3 months postoperatively.

pH-responsive albumin-mimetic synthetic nanoprobes for magnetic resonance/fluorescence imaging of thyroid cancer.

The combination of magnetic resonance and fluorescence imaging in dual-modality imaging not only resolves the limitations of conventional single molecular imaging techniques in terms of specificity, sensitivity, and resolution but also expands the possibilities of molecular imaging techniques in diagnostics and therapeutic monitoring. Herein, a novel pH-responsive magnetic resonance/near-infrared fluorescence (MR/NIRF) nanoprobe (MnO2@BSA-Cy5.5) was successfully prepared by biomineralizing manganese dioxide (MnO2) with bovine serum albumin (BSA) while coupling fluorescent dye Cy5.5 for precise tumor detection and visualization. The synthesized MnO2@BSA-Cy5.5 nanoprobes were spherical particles of approximately 22.62 ± 3.31 nm in size, and their relaxation rates and T1 imaging signals were activated-enhanced in an acidic environment. Cytotoxicity assay and hematoxylin and eosin staining demonstrated that MnO2@BSA-Cy5.5 had low cytotoxicity and good biocompatibility. More importantly, active targeting via solid tumor albumin-binding protein receptor and enhanced permeability and retention effect, the probe can be specifically aggregated to the tumor site of the 8305C tumor model and exhibit excellent MR/NIRF imaging properties. Our results show that MnO2@BSA-Cy5.5 has high resolution and sensitivity in tumor imaging and is expected to be applied as an MR/NIRF contrast agent for accurate diagnosis of thyroid cancer.

Esophageal squamous cell carcinoma metastases to kidney and renal hilar lymph nodes through epithelial-mesenchymal transition: a case report and literature review.

BACKGROUND: Esophageal cancer (EC) metastasized to the kidney is extremely rare clinically. Here, we present a case of metachronous renal metastasis of esophageal squamous cell carcinoma (ESCC) through epithelial-mesenchymal transition (EMT). CASE PRESENTATION: A 60-year-old patient, male, complained of left waist pain for 5 days, 11 months after radical esophagectomy. Laboratory tests revealed haematuria. Both CT and PET-CT scan showed retroperitoneal lymph nodes and left renal masses. Subsequently the patient received a left nephrectomy and lymph nodes resection, and squamous cell carcinoma of kidney and renal hilar lymph nodes was diagnosed, combined with morphology, medical history and immunophenotype, it was presumed to be metastasis of ESCC through the EMT pathway. CONCLUSIONS: The renal metastasis of squamous cell carcinoma should be considered in patients with history of EC, although this is very rare. Histopathological examination combined with immunochemical detection is helpful in differential diagnosis.

Behavior characteristics of bimolecular reactive transport in heterogeneous porous media.

In order to study the mechanism of bimolecular reactive solute transport in heterogeneous porous media, the chemical reaction (CuSO4 + Na2EDTA2-→CuEDTA2) was carried out by laboratory experiments and numerical simulation in heterogeneous porous media. Three different kinds of heterogeneous porous media (Sd2 = 1.72, 1.67 and 0.80 mm2) and flow rates (1.5, 2.5 and 5.0 mL/s) were considered. The increase of flow rate would promote the mixing between reactants, resulting in a greater peak value and a slighter "tailing" of product concentration, while the increase of medium heterogeneity would result in a more significant "tailing". It was found that the concentration breakthrough curves of reactant CuSO4 had a peak in the early stage of the transport, and the peak value increased with the increase of flow rate and medium heterogeneity. The concentration peak of CuSO4 was caused by the delayed mixing and reaction of reactants. The IM-ADRE (The advection-dispersion-reaction equation considering incomplete mixing) model could well simulate the experimental results. The simulation error of IM-ADRE model for the concentration peak of product was less than 6.15%, and the fitting accuracy for "tailing" increased with the increase of flow. The dispersion coefficient increased logarithmically with the increase of flow, and was negatively correlated to the heterogeneity of the medium. In addition, the dispersion coefficient of CuSO4 simulated by IM-ADRE model was one order of magnitude larger than that simulated by ADE model, indicating that the reaction promoted dispersion.

Efficacy of perioperative cryotherapy combined with intra-articular injection of tranexamic acid in total knee arthroplasty.

OBJECTIVE: To evaluate the efficacy and safety of perioperative cryotherapy combined with intra-articular injection of tranexamic acid (TXA) in total knee arthroplasty (TKA) and explore a new strategy of enhanced recovery after TKA. METHODS: We randomly divided 200 patients into 4 groups: normal saline (10 mL) by drainage (Group A, placebo); intra-articular injection of TXA (1 g, 10 mL, Group B); normal saline (10 mL) and continuous cryotherapy postoperatively (Group C) and intra-articular injection of TXA (1 g, 10 mL) and continuous cryotherapy postoperatively (Group D). Primary outcomes were blood loss volume, postoperative pain and circumference variation. We also recorded consumption of analgesics, postoperative length of stay (p-LOS), range of motion (ROM), function score (Hospital for Special Surgery) and severe complications. RESULTS: There were statistically significant differences in postoperative drainage volume, total blood loss, hidden blood loss, and visual analogue scale at rest and walking on postoperative day 1 (POD1), POD2, POD3, ROM (POD3, 7, discharge, postoperative month), circumference variation (POD3, 7), p-LOS, Hospital for Special Surgery score (discharge) and drop of hemoglobin on POD3 (P < .05) among 4 groups, but there were no significant differences in intraoperative blood loss, postoperative prothrombin, activated partial thromboplastin time, overall number of patients or total consumption of oxycodone and perioperative complications (e.g., incidence of surgical site infection, deep venous thrombosis, and cold injury) among them (P > .05). CONCLUSION: Continuous cryotherapy combined with intra-articular injection of TXA provides short-term advantages in reducing blood loss, pain, postoperative swelling, p-LOS and increasing ROM and joint function in the early postoperative period after TKA without increasing any severe complications.

Synthesizing MOF-derived NiNC catalyst via surfactant modified strategy for efficient electrocatalytic CO2 to CO.

Recently, Ni, N-doped carbon (NiNC) electrocatalysts synthesized using metal-organic frameworks (MOFs) as templates have demonstrated attractive catalytic performances in the CO2 reduction reaction (CO2RR). However, most of the reported preparations of MOFs-based precursors are carried out in organic solvents, and the resulting NiNC materials have relatively low metal loadings and mainly exhibit microporous structures, which is unfavorable for the mass transport. Herein, Ni, N-doped meso-microporous carbon electrocatalysts with a range of Ni loadings (M-NiNCx/CNTs) were prepared by the pyrolysis of MOFs-based precursors synthesized in aqueous solution using the surfactant cetyltrimethylammonium bromide (CTAB) as a modifier to promote the adsorption of Ni2+ ions and the formation of mesopores. Owing to the unique morphology, porous structure and high contents of Ni-Nx sites and pyrrolic-N, the optimal catalyst (M-NiNC2/CNTs) shows superior electrocatalytic activity for the CO2RR with a maximum CO Faradaic efficiency (FECO) of 98 % at -0.7 V vs. reversible hydrogen electrode (RHE), and the FECO can reach over 80 % in a wide potential range of -0.5 to -1.0 V vs. RHE. This work develops a facile and environmentally friendly strategy to obtain high-performance and low-cost transition metal-nitrogen-doped porous carbon electrocatalysts for the CO2RR.

Dexamethasone with aggressive warming facilitates pain reduction, reduced blood loss, and quicker recovery after total hip arthroplasty.

This study aimed to evaluate the optimal frequency of dexamethasone (DEX) administration and the efficacy of DEX with aggressive warming in total hip arthroplasty (THA), which remains unclear. A total of 150 patients were treated with DEX (10 mg) once before and once or twice after surgery with or without intraoperative aggressive warming. On postoperative day 3, the dynamic visual analogue scale scores and C-reactive protein (CRP) and interleukin-6 (IL-6) levels in participants administered with DEX twice after surgery were significantly lower than those who did not receive the second dose. The range of motion (ROM), postoperative fatigue based on Identity-Consequence-Fatigue Scale, average temperature at different stages, intraoperative blood loss, and postoperative drainage volume in patients who were subjected to warming were significantly higher than those who were not. The degree of satisfaction was also higher in the patients who received both second dose and warming than those who received neither. No differences in complications were observed based on the treatments. An additional dose of DEX at 48 h post-surgery has short-term advantages in terms of analgesia, anti-inflammatory effects, and accelerated rehabilitation after THA. DEX combined with aggressive warming further optimises short-term ROM and fatigue and improves the degree of satisfaction.Clinical trial was registered in the International Clinical Trial Registry, and the date of registration is 2/12/2020 (ChiCTR2000040560).

The efficacy of temperature intervention combined with tranexamic acid in reducing blood loss and accelerating recovery during spinal fusion.

OBJECTIVE: This study aimed to evaluate the effect of temperature intervention combined with tranexamic acid (TXA) on perioperative blood loss during spinal fusion and accelerated rehabilitation. METHOD: Between August 2014 and July 2019, 310 lumbar fusion at our hospital were randomly divided into 4 groups as follows. Group A (placebo): no TXA and no temperature intervention. Group B: TXA (15 mg/kg) before skin incision. Group C: TXA (15 mg/kg) before skin incision and temperature intervention. Group D: temperature intervention without TXA. The primary outcomes were intraoperative blood loss, postoperative blood loss, total blood loss, and core temperature at different stages. We also recorded the hemoglobin level, blood transfusion rate, prothrombin time on postoperative day 1 (POD1), length of hospital stay, and the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE). RESULTS: The 4 groups showed statistically significant differences in intraoperative blood loss, postoperative blood loss, total blood loss, core temperature after anesthesia, average temperature during the operation, hemoglobin on POD1, and length of stay (P < .05). In contrast, prothrombin time on POD1 and the incidence of DVT or PE did not differ between the groups (P > .05). Comparing the transfusion rate in Group C (6/77, 7.79%) and Group A (17/78, 21.79%), the difference was statistically significant. CONCLUSION: Temperature intervention combined with TXA can significantly reduce blood loss and the transfusion rate of spinal fusion in the perioperative period, reduce the length of stay and accelerate rehabilitation after surgery without increasing the incidence of DVT or PE.

Highly selective fluorescent probe for detecting mercury ions in water.

Mercury ion (Hg2+) is a well-known toxic heavy metal. It has become one of the most significant environmental pollutants in the world because of its serious physiological toxicity, persistence, easy migration, and high bioconcentration. Thus, the development of methods for monitoring Hg2+ is indispensable. Herein, we have designed and synthesized a new fluorescent probe, TPH, for the detection of Hg2+ in the water environment. The TPH probe could quantitatively detect Hg2+ between 0 and 5 µM (LOD = 16 nM), with a linear range of 0-2.5 µM. In addition, the TPH probe was used to monitor Hg2+ in water samples successfully. Thus, this probe is suitable for monitoring Hg2+ in the actual water environment.

Amidoxime modified Fe3O4@TiO2 particles for antibacterial and efficient uranium extraction from seawater.

Uranium extraction and recovery play a critical role in guaranteeing the sustainable nuclear energy supply and protecting the environmental safety. The ideal uranium sorbents possess high adsorption capacity, excellent selectivity and reusability, as well as outstanding antimicrobial property, which are greatly desired for the real application of uranium extraction from seawater. To address this challenge, a novel magnetic core-shell adsorbent was designed and fabricated by a facile method. The obtained amidoximed Fe3O4@TiO2 particles (Fe3O4@TiO2-AO) achieved equilibrium in 2 h and the maximum adsorption capacity calculated from Langmuir model is 217.0 mg/g. The adsorption kinetics followed the pseudo-second-order model. Meanwhile, the Fe3O4@TiO2-AO exhibited great selectivity when competitive metal ions and anions coexisted. In addition, the magnetic Fe3O4@TiO2-AO could be conveniently separated and collected by an external magnetic field, the regeneration efficiency maintained at 78.5% even after ten adsorption-desorption cycles. In natural seawater, the uranium uptake reached 87.5 µg/g in 33 days. Furthermore, the TiO2 contained adsorbent showed effective photo induced bactericidal properties against both E. coli and S. aureus. The Fe3O4@TiO2-AO with great U(VI) adsorption performance is highly promising in uranium extraction and reclamation.

Synthesizing ordered mesoporous Ni spheres with uniform and adjustable size through a one-step Pd2+-assisted soft-templating strategy.

Developing an effective way to synthesize uniform ordered mesoporous metal spheres with controllable diameter is important for enhancing their performance in various applications but remains a challenge. Herein, a one-step and facile Pd2+-assisted soft-templating strategy is reported to synthesize ordered mesoporous Ni spheres (OMNiS) with highly uniform and tunable diameters. In this synthesis methodology, lyotropic liquid crystals (LLCs) are used as a meso-structural template and Pd nuclei obtained from the reduction of Pd2+ ions are used as nucleation sites for directing Ni deposition. The OMNiS samples with average sphere diameter ranging from 50 nm to 190 nm are produced by varying the amount of Pd2+ in the LLC precursor, revealing that the Pd nuclei play a key role in improving the uniformity of the mesoporous Ni spheres and adjusting the sphere diameter. The satisfactory combination of uniform sphere size, high surface area, great conductivity, and highly ordered mesoporous structure for the optimal OMNiS-100 sample contributes to its superior electrocatalytic activity for the oxygen evolution reaction (OER) in an alkaline electrolyte with a low overpotential of 271 mV to drive a current density of 10 mA cm-2, which is much smaller than that of RuO2 (368 mV), along with a remarkable durability.