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Synthetic inhibitors of the serine protease DPP9 activate the related NLRP1 and CARD8 inflammasomes and stimulate powerful innate immune responses. Thus, it seems plausible that a biomolecule similarly inhibits DPP9 and triggers inflammasome activation during infection, but one has not yet been discovered. Here, we wanted to identify and characterize DPP9-binding proteins to potentially uncover physiologically relevant mechanisms that control DPP9's activity. Notably, we found that the redox sensor protein KEAP1 binds to DPP9 in an inactive conformation and stabilizes this non-native fold. At the same time, this inactive form of DPP9 reciprocally inhibits the ability of KEAP1 to bind to and degrade the transcription factor NRF2, thereby inducing an antioxidant response. Although we discovered several experimental conditions, for example new protein expression and chemical denaturation, that force DPP9 out of its folded dimeric state and into a KEAP1-binding state, the key danger-related stimulus that causes this critical DPP9 conformational change is not yet known. Regardless, our data now reveal that an endogenous DPP9 inhibition mechanism does in fact exist, and moreover that DPP9, like the other NLRP1 regulator thioredoxin-1, is directly coupled to the intracellular redox potential. Overall, we expect this work will provide the foundation to discover additional biomolecules that regulate DPP9's activity, the DPP9-KEAP1 interaction, the intracellular redox environment, and the NLRP1 and CARD8 inflammasomes., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

SARS-CoV-2 vaccine-acquired immunity provides robust cross-variant recognition, while infection-acquired immunity can be heterogenous, with disease severity often modulating post-recovery responses. We assessed antibody waning dynamics between infection- and vaccination-acquired immunity across variants of concern (VOC). mRNA vaccination induced potent, cross-VOC Spike recognition and functional responses, but waned more rapidly for Omicron Spike. Hospitalized individuals developed more durable functional responses with lower peaks compared to mRNA vaccination, while outpatients exhibited slower decay than inactivated vaccine recipients. Humoral decay for the receptor binding domain tracked with neutralizing antibody titers, while S2-directed responses tracked with antibody-dependent myeloid cellular phagocytosis. Boosting the recovered patients with mRNA or inactivated vaccines expanded humoral breadth, durability, and restored functional responses, eliminating the severity- and platform-associated decay differences. Therefore, post-recovery hybrid immunization compensates for this distinction and broadens humoral breadth, highlighting the value of boosting immunity in previously infected individuals., Competing Interests: Competing Interests: The authors declare the following competing interests; Galit Alter is a founder/equity holder in Seroymx Systems and Leyden Labs. G.A. has served as a scientific advisor for Sanofi Vaccines. G.A. has collaborative agreements with GSK, Merck, Abbvie, Sanofi, Medicago, BioNtech, Moderna, BMS, Novavax, SK Biosciences, Gilead, and Sanaria. R.A.M. has served as a scientific advisor for Valneva SE. The remaining authors declare no competing interests.

Mounting evidence indicates that proteotoxic stress is a primary activator of the CARD8 inflammasome, but the complete array of signals that control this inflammasome have not yet been established. Notably, we recently discovered that several hydrophobic radical-trapping antioxidants (RTAs), including JSH-23, potentiate CARD8 inflammasome activation through an unknown mechanism. Here, we report that these RTAs directly alkylate several cysteine residues in the N-terminal disordered region of CARD8. These hydrophobic modifications destabilize the repressive CARD8 N-terminal fragment and accelerate its proteasome-mediated degradation, thereby releasing the inflammatory CARD8 C-terminal fragment from autoinhibition. Consistently, we also found that unrelated (non-RTA) hydrophobic electrophiles as well as genetic mutation of the CARD8 cysteine residues to isoleucines similarly potentiate inflammasome activation. Overall, our results not only provide further evidence that protein folding stress is a key CARD8 inflammasome-activating signal, but also indicate that the N-terminal cysteines can play key roles in tuning the response to this stress., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Candida is one of the common pathogens in nosocomial infections. Culture is the gold standard for diagnosing candidemia. Candida albicans is identified via the germ tube test, which uses serum as the culture medium, which is costly and time-consuming. This study was conducted to evaluate and compare a relatively simple, fast, and reliable method for the detection of Candida albicans ., Methods: We conducted this randomized case study at Taipei City Hospital (TCH) from January 2023 to August 2023, with a total of 30 specimen culture reports collected and confirmed to be cases of Candida albicans infection. A germ tube test was performed in a 37°C water bath using serum, plasma, and safe plasma products (Fresh Frozen Plasma, FFP). Further, the same procedures were repeated with the addition of 22% bovine serum albumin (BSA) to the identification/culture., Results: By adding BSA, more than 50% of the budding phenomenon was observed in 40 minutes, which shortened the diagnosis time compared with the traditional method (2-3 hours). Using BSA can shorten the identification time for early clinical medication and improve the quality of medical care., Conclusion: Using safer plasma products for germ tube test of candidiasis not only reduced the risk of infection for medical technicians but could also replace the serum used in traditional methods to increase convenience and save time. This study proposed BSA as a germ tube induction medium enhancer, which reduced the culture time, thereby enabling quicker diagnosis of C. albicans infections., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Mounting evidence indicates that antibodies can contribute towards control of tuberculosis (TB). However, the underlying mechanisms of humoral immune protection and whether antibodies can be exploited in therapeutic strategies to combat TB are relatively understudied. Here we engineered the receptor-binding Fc (fragment crystallizable) region of an antibody recognizing the Mycobacterium tuberculosis (Mtb) capsule, to define antibody Fc-mediated mechanism(s) of Mtb restriction. We generated 52 Fc variants that either promote or inhibit specific antibody effector functions, rationally building antibodies with enhanced capacity to promote Mtb restriction in a human whole-blood model of infection. While there is likely no singular Fc profile that universally drives control of Mtb, here we found that several Fc-engineered antibodies drove Mtb restriction in a neutrophil-dependent manner. Single-cell RNA sequencing analysis showed that a restrictive Fc-engineered antibody promoted neutrophil survival and expression of cell-intrinsic antimicrobial programs. These data show the potential of Fc-engineered antibodies as therapeutics able to harness the protective functions of neutrophils to promote control of TB., (© 2024. The Author(s).)

NLRP1 is an innate immune receptor that detects pathogen-associated signals, assembles into a multiprotein structure called an inflammasome, and triggers a proinflammatory form of cell death called pyroptosis. We previously discovered that the oxidized, but not the reduced, form of thioredoxin-1 directly binds to NLRP1 and represses inflammasome formation. However, the molecular basis for NLRP1's selective association with only the oxidized form of TRX1 has not yet been established. Here, we leveraged AlphaFold-Multimer, site-directed mutagenesis, thiol-trapping experiments, and mass spectrometry to reveal that a specific cysteine residue (C427 in humans) on NLRP1 forms a transient disulfide bond with oxidized TRX1. Overall, this work demonstrates how NLRP1 monitors the cellular redox state, further illuminating an unexpected connection between the intracellular redox potential and the innate immune system., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nuclear factor kappa B (NF-κB) is a key regulator in immune signaling and is known to exhibit a digital activation pattern. Yet the molecular basis underlying the heterogeneity in NF-κB activation at single-cell level is not entirely understood. Here, we show that NF-κB activation in single cells is largely regulated by intrinsic differences at the receptor level. Using the genome editing and time-lapse imaging, we directly characterize endogenous TNFR1 dynamics and NF-κB activation from the same single cells. Total internal reflection fluorescence (TIRF) microscopy shows that endogenous TNFR1 forms pre-ligand clusters in the resting cells. Upon tumor necrosis factor (TNF) stimulation, the diffusion coefficient of membrane TNFR1 was significantly decreased and a substantial level of TNFR1 undergoes oligomerization to form trimers and hexamers. Moreover, multi-color cell imaging reveals that both digital and graded information processing regulate NF-κB activation across different TNFR1 expression levels. Our results indicate that single-cell NF-κB activation potential strongly correlates with its TNFR1 characteristics., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

Multicolor labeling for monitoring the intracellular localization of the same target type in the native environment using chemical fluorescent dyes is a challenging task. This approach requires both bioorthogonal and biocompatible ligations with an excellent fluorescence signal-to-noise ratio. Here, we present a metabolic glycan labeling technique that uses homemade fluorogenic dyes to investigate glycosylation patterns in live cells. These dyes allowed us to demonstrate rapid and efficient simultaneous multilabeling of glycoconjugates with minimum fluorescence noise. Our results demonstrate that this approach is capable of not only probing sialylation and GlcNAcylation in cells but also specifically labeling the cell-surface and intracellular sialylated glycoconjugates in live cells. In particular, we performed site-specific dual-channel fluorescence imaging of extra and intracellular sialylated glycans in HeLa and PC9 cancer cells as well as identified fluorescently labeled sialylated glycoproteins and glycans by a direct enrichment approach combined with an MS-based proteomic analysis in the same experiment. In conclusion, this study provides multilabeling tools in cellular systems for simultaneous site-specific glycan imaging and glycoproteomic analysis to study potential cancer- and disease-associated glycoconjugates., (© 2023 Wiley-VCH GmbH.)

The study evaluated the prevalence of gonorrhoea and chlamydia infections and find out other non-infectious diseases in sexually active young males with urethritis-like symptoms and their treatment outcomes. We retrospectively reviewed the young adult males (aged 20-50 years) who visited our clinic with urethritis symptoms from March 2019 to April 2022. All patients underwent urinalysis, urine culture, and urinary polymerase chain reaction (PCR) testing for gonorrhoea and chlamydia. Student's t-test and Pearson's chi-square test were used to compare the differences between the triple-negative group (i.e., negative results in urinalysis, urine culture, and urinary PCR) and the any-positive group. Logistic regression analyses were used to evaluate the predictive factors for positive PCR results for gonorrhoea or chlamydia in patients with negative urinalysis and urine culture. Of the 365 participants with urethritis-like symptoms, 139 patients were diagnosed of gonococcal or chlamydia urethritis. Among the 202 patients with negative urinalysis and urine culture, 60 patients were diagnosed with gonorrhoea or chlamydia using PCR. Urethral discharge was an independent predictor. 142 patients with triple negative results were attributed to other non-infectious diseases. Empirical antibiotic treatment is recommended for patients with urethritis symptoms showing positive or negative urinalysis results but with urethral discharge., (© 2023. Springer Nature Limited.)

Secondary mutation, T790M, conferring tyrosine kinase inhibitors (TKIs) resistance beyond oncogenic epidermal growth factor receptor (EGFR) mutations presents a challenging unmet need. Although TKI-resistant mechanisms are intensively investigated, the underlying responses of cancer cells adapting drug perturbation are largely unknown. To illuminate the molecular basis linking acquired mutation to TKI resistance, affinity purification coupled mass spectrometry was adopted to dissect EGFR interactome in TKI-sensitive and TKI-resistant non-small cell lung cancer cells. The analysis revealed TKI-resistant EGFR-mutant interactome allocated in diverse subcellular distribution and enriched in endocytic trafficking, in which gefitinib intervention activated autophagy-mediated EGFR degradation and thus autophagy inhibition elevated gefitinib susceptibility. Alternatively, gefitinib prompted TKI-sensitive EGFR translocating toward cell periphery through Rab7 ubiquitination which may favor efficacy to TKIs suppression. This study revealed that T790M mutation rewired EGFR interactome that guided EGFR to autophagy-mediated degradation to escape treatment, suggesting that combination therapy with TKI and autophagy inhibitor may overcome acquired resistance in non-small cell lung cancer., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The decision between local and free tissue coverage for distal lower leg defects has long been dictated by the location and size of defects. Recent reports of distal defects treated successfully with pedicled perforator flaps demonstrate equivalent clinical outcomes; however, the complication rate can be high. The goal of this study was to evaluate the cost equivalence of free versus pedicled perforator flap to assist decision-making and guide clinical care., Methods: The institutional database was searched for patients with acute injury over the distal lower extremity requiring free or pedicled perforator flap. Demographic, clinical, and total resource cost was gathered. Patients were matched to Gustilo-Anderson or Arbeitsgemeinschaft fur Osteosynthesefragen classification as well as size of defect and outcomes, and cost compared., Results: We have included 108 free flaps and 22 pedicled perforator flaps in the study. There was no difference in complication rate between groups. Free flaps had significantly more reoperations, required longer operative time, and had longer intensive care unit (ICU) care with higher cost of surgery and overall cost than pedicled flaps. When controlling for size of defect, surgical cost remained significantly different between groups ( p  = 0.013), but overall cost did not. Multivariable regression analysis indicated flap type to be the primary driver of cost of surgery, while body mass index elevated the total cost., Conclusion: Pedicled perforator flap coverage for small to medium-sized defects (< 70 cm 2 ) is a viable and cost-effective option for distal lower leg soft tissue reconstruction after acute traumatic injury with similar clinical outcomes and shorter operative duration and ICU stay., Competing Interests: None declared., (Thieme. All rights reserved.)

Efficiently delivering liposomal content to cells in a relatively uniform dose and patterned fashion, especially bypassing the degradative endocytosis pathway, is an important technology in cell culture and potentially to tissue engineering that still remains challenging. We developed a "nano-on-nano" platform technology that consists of the following three material features: (1) high density silicon nanopillars to create a pseudo-3-dimensional nanoenvironment for cell culturing, (2) thermoresponsive polymer grafted onto silicon nanopillars to form a responsive nanosubstrate, and (3) immobilized liposomes using a biotin-streptavidin-biotin conjugation. The working principle is that the liposomes are detached for cellular uptake upon thermal stimulation and high local liposome concentration between the cells and substrates drives the cellular uptake with nonendocytic pathways. Cryo-EM images confirms that liposomes are attached to form liposome-warped nanopillars. Upon thermal stimulation, an 8 times higher increase in the liposomal fluorescence intensity is observed compared to the conventional solution-phase liposome delivery, indicating that high local concentration drives liposome uptake with greater efficiency. Moreover, preliminary mechanistic studies reveal that these liposomes are taken up by nonendocytic pathways. The ability of our nano-on-nano delivery system that achieves efficient dose-uniform cellular delivery can open a unique era in cell and tissue engineering by controlling cell behaviors with the delivery of bioactive ingredient-loaded liposomes.

Inflammasomes are innate immune signaling platforms that trigger pyroptotic cell death. NLRP1 and CARD8 are related human inflammasomes that detect similar danger signals, but NLRP1 has a higher activation threshold and triggers a more inflammatory form of pyroptosis. Both sense the accumulation of intracellular peptides with Xaa-Pro N-termini, but Xaa-Pro peptides on their own without a second danger signal only activate the CARD8 inflammasome. We recently reported that a dual inhibitor of the Xaa-Pro-cleaving M24B aminopeptidases PEPD and XPNPEP1 called CQ31 selectively activates the CARD8 inflammasome by inducing the build-up of Xaa-Pro peptides. Here, we performed structure-activity relationship studies on CQ31 to develop the optimized dual PEPD/XPNPEP1 inhibitor CQ80 that more effectively induces CARD8 inflammasome activation. We anticipate that CQ80 will become a valuable tool to study the basic biology and therapeutic potential of selective CARD8 inflammasome activation.

The danger signals that activate the related nucleotide-binding domain leucine-rich repeat pyrin domain-containing 1 (NLRP1) and caspase activation and recruitment domain-containing 8 (CARD8) inflammasomes have not been fully established. We recently reported that the oxidized form of TRX1 binds to NLRP1 and represses inflammasome activation. These findings suggested that intracellular reductive stress, which would reduce oxidized TRX1 and thereby abrogate the NLRP1-TRX1 interaction, is an NLRP1 inflammasome-activating danger signal. However, no agents that induce reductive stress were known to test this premise. Here, we identify and characterize several radical-trapping antioxidants, including JSH-23, that induce reductive stress. We show that these compounds accelerate the proteasome-mediated degradation of the repressive N-terminal fragments of both NLRP1 and CARD8, releasing the inflammasome-forming C-terminal fragments from autoinhibition. Overall, this work validates chemical probes that induce reductive stress and establishes reductive stress as a danger signal sensed by both the NLRP1 and CARD8 inflammasomes., Competing Interests: Declaration of interests MSKCC has filed for patent protection on behalf of D.A.B. and Q.W. for inventions relating to the induction of reductive stress., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Aeromonas necrotizing fasciitis (NF) causes high rates of amputation and mortality, even after aggressive surgical debridement and antibacterial therapy. This study investigated the effects of rational use of antibiotics and education by infectious disease (ID) physicians on Aeromonas NF treatment outcomes., Methods: Retrospective review for conducted for four years (period I, without an ID physician, December 2001 to December 2005) and 15 years (period II, with an ID physician, January 2006 to March 2021). In period II, the hospital-wide computerized antimicrobial approval system (HCAAS) was also implemented. A pretest-posttest time series analysis compared the two periods. Differences in clinical outcomes, demographics, comorbidities, signs and symptoms, laboratory findings, Aeromonas antibiotic susceptibility, and antibiotic regimens were compared between the two periods., Results: There were 19 patients in period I and 53 patients in period II. Patients had a lower rate of amputation or mortality in period II (35.8%) compared with period I (63.2%). Forty-four patients (61.1%) had polymicrobial infections. In the emergency room, the rate of misdiagnosis decreased from 47.4% in period I to 28.3% in period II, while effective empiric antibiotic usage increased from 21.1% in period I to 66.0% in period II. After the ID physician's adjustment, 69.4% received monotherapy in period II compared to 33.3% in period I., Conclusions: Because Aeromonas NF had a high mortality rate and was often polymicrobial, choosing an antibiotic regimen was difficult. Using the HCAAS by an experienced ID physician can improve rational antibiotic usage and clinical outcomes in Aeromonas NF.

Bacterial and viral pathogens can modulate the glycosylation of key host proteins to facilitate pathogenesis by using various glycosidases, particularly sialidases. Epidermal growth factor receptor (EGFR) signaling is activated by ligand-induced receptor dimerization and oligomerization. Ligand binding induces conformational changes in EGFR, leading to clusters and aggregation. However, information on the relevance of EGFR clustering in the pattern of glycosylation during bacterial and viral invasion remains unclear. In this study, (1) we established CRISPR/Cas9-mediated GFP knock-in (EGFP-KI) HeLa cells expressing fluorescently tagged EGFR at close to endogenous levels to study EGF-induced EGFR clustering and molecular dynamics; (2) We studied the effect of sialylation on EGF-induced EGFR clustering and localization in live cells using a high content analysis platform and raster image correlation spectroscopy (RICS) coupled with a number and brightness (N&B) analysis; (3) Our data reveal that the removal of cell surface sialic acids by sialidase treatment significantly decreases EGF receptor clustering with reduced fluorescence intensity, number, and area of EGFR-GFP clusters per cell upon EGF stimulation. Sialylation appears to mediate EGF-induced EGFR clustering as demonstrated by the change of EGFR-GFP clusters in the diffusion coefficient and molecular brightness, providing new insights into the role of sialylation in EGF-induced EGFR activation; and (4) We envision that the combination of CRISPR/Cas9-mediated fluorescent tagging of endogenous proteins and fluorescence imaging techniques can be the method of choice for studying the molecular dynamics and interactions of proteins in live cells.

CARD8 is a pattern-recognition receptor that forms a caspase-1-activating inflammasome. CARD8 undergoes constitutive autoproteolysis, generating an N-terminal (NT) fragment with a disordered region and a ZU5 domain and a C-terminal (CT) fragment with UPA and CARD domains. Dipeptidyl peptidase 8 and dipeptidyl peptidase 9 inhibitors, including Val-boroPro, accelerate the degradation of the NT fragment via a poorly characterized proteasome-mediated pathway, thereby releasing the inflammatory CT fragment from autoinhibition. Here, we show that the core 20S proteasome, which degrades disordered and misfolded proteins independent of ubiquitin modification, controls activation of the CARD8 inflammasome. In unstressed cells, we discovered that the 20S proteasome degrades just the NT disordered region, leaving behind the folded ZU5, UPA, and CARD domains to act as an inhibitor of inflammasome assembly. However, in Val-boroPro-stressed cells, we show the 20S proteasome degrades the entire NT fragment, perhaps due to ZU5 domain unfolding, freeing the CT fragment from autoinhibition. Taken together, these results show that the susceptibility of the CARD8 NT domain to 20S proteasome-mediated degradation controls inflammasome activation., Competing Interests: Conflicts of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Accurate glioma subtype classification is critical for the treatment management of patients with brain tumors. Developing an automatically computer-aided algorithm for glioma subtype classification is challenging due to many factors. One of the difficulties is the label constraint. Specifically, each case is simply labeled the glioma subtype without precise annotations of lesion regions information. In this paper, we propose a novel hybrid fully convolutional neural network (CNN)-based method for glioma subtype classification using both whole slide imaging (WSI) and multiparametric magnetic resonance imagings (mpMRIs). It is comprised of two methods: a WSI-based method and a mpMRIs-based method. For the WSI-based method, we categorize the glioma subtype using a 2D CNN on WSIs. To overcome the label constraint issue, we extract the truly representative patches for the glioma subtype classification in a weakly supervised fashion. For the mpMRIs-based method, we develop a 3D CNN-based method by analyzing the mpMRIs. The mpMRIs-based method consists of brain tumor segmentation and classification. Finally, to enhance the robustness of the predictions, we fuse the WSI-based and mpMRIs-based results guided by a confidence index. The experimental results on the validation dataset in the competition of CPM-RadPath 2020 show the comprehensive judgments from both two modalities can achieve better performance than the ones by solely using WSI or mpMRIs. Furthermore, our result using the proposed method ranks the third place in the CPM-RadPath 2020 in the testing phase. The proposed method demonstrates a competitive performance, which is creditable to the success of weakly supervised approach and the strategy of label agreement from multi-modality data., (© 2022. The Author(s).)

Solvatofluorochromism, a solvation effect on the fluorescence color of an organic dye, is a property generally limited to fluid solutions. We demonstrate herein the concept of solid-state solvatofluorochromism by using an organogelator ( 1 -SG), which consists of a solvatofluorochromic green fluorescence protein (GFP) chromophore ( 1 ) and a sugar gelator (SG). While 1 -SG could be located in the liquid phase or in the fibrous solid matrix of the SG gel, our results show that the one in the solid matrix but near the liquid interface has superior fluorescence stability and quantum efficiency as well as solvatofluorochromicity than the one in the liquid phase. In addition, the phenomenon of fluorescence turn-on occurs when the gel is formed in protic solvents. These features have been applied to perform multicolor fluorescence patterning, chemical vapor sensing, data encryption and decryption, and real-time fluorescence cell imaging.

Respiratory syncytial virus (RSV) infection is a major cause of respiratory illness in infants and the elderly. Although several vaccines have been developed, none have succeeded in part due to our incomplete understanding of the correlates of immune protection. While both T cells and antibodies play a role, emerging data suggest that antibody-mediated mechanisms alone may be sufficient to provide protection. Therefore, to map the humoral correlates of immunity against RSV, antibody responses across six different vaccines were profiled in a highly controlled nonhuman primate-challenge model. Viral loads were monitored in both the upper and lower respiratory tracts, and machine learning was used to determine the vaccine platform-agnostic antibody features associated with protection. Upper respiratory control was associated with virus-specific IgA levels, neutralization, and complement activity, whereas lower respiratory control was associated with Fc-mediated effector mechanisms. These findings provide critical compartment-specific insights toward the rational development of future vaccines., Competing Interests: Declaration of interests Galit Alter is a founder of SeromYx Systems., (Copyright © 2021. Published by Elsevier Inc.)

Thermoelectric materials are considered promising candidates for thermal energy conversion. This study presents the fabrication of Zn- and Ce-alloyed In 2 O 3 with a porous structure. The electrical conductivity was improved by the alloying effect and an ultra-low thermal conductivity was observed owing to the porous structure, which concomitantly provide a distinct enhancement of ZT . However, SiO 2 nanoparticle additives react with the matrix to form a third-phase impurity, which weakens the electrical conductivity and increases the thermal conductivity. A thermoelectric module was constructed for the purpose of thermal heat energy conversion. Our experimental results proved that both an enhancement in electrical conductivity and a suppression in thermal conductivity could be achieved through nano-engineering. This approach presents a feasible route to synthesize porous thermoelectric oxides, and provides insight into the effect of additives; moreover, this approach is a cost-effective method for the fabrication of thermoelectric oxides without traditional hot-pressing and spark-plasma-sintering processes., (© 2022 IOP Publishing Ltd.)