Artificial Intelligence in battling infectious diseases: A transformative role.

It is widely acknowledged that infectious diseases have wrought immense havoc on human society, being regarded as adversaries from which humanity cannot elude. In recent years, the advancement of Artificial Intelligence (AI) technology has ushered in a revolutionary era in the realm of infectious disease prevention and control. This evolution encompasses early warning of outbreaks, contact tracing, infection diagnosis, drug discovery, and the facilitation of drug design, alongside other facets of epidemic management. This article presents an overview of the utilization of AI systems in the field of infectious diseases, with a specific focus on their role during the COVID-19 pandemic. The article also highlights the contemporary challenges that AI confronts within this domain and posits strategies for their mitigation. There exists an imperative to further harness the potential applications of AI across multiple domains to augment its capacity in effectively addressing future disease outbreaks.

The effect of probiotics supplementation on cancer-treatment complications: a critical umbrella review of interventional meta-analyses.

Cancer-related complications pose significant challenges in the management and treatment of patients with malignancies. Several meta-analyses have indicated improving effects of probiotics on cancer complications, while some studies have reported contentious findings. The purpose of the present study was to evaluate the efficacy of probiotics in addressing cancer complications, including diarrhea, mucositis, and infections, following chemotherapy, radiotherapy, and surgery. Relevant studies were searched in the PubMed, Scopus, Embase and Web of Science databases and Google Scholar up to September 2023. All meta-analyses addressing the effects of probiotics on all cancer treatments-induced complications including infection, diarrhea and oral mucositis were included. The pooled results were calculated using a random-effects model. Analyses of subgroups, sensitivity and publication bias were also conducted. The results revealed that the probiotics supplementation was effective on reduction of total cancer complications (OR:0.53; 95% CI: 0.44, 0.62, p < 0.001; I2=79.0%, p < 0.001), total infection rate (OR:0.47; 95%CI: 0.41, 0.52, p < 0.001; I2= 48.8%, p < 0.001); diarrhea (OR:0.50; 95%CI: 0.44, 0.57, p < 0.001; I2=44.4%, p = 0.023) and severe diarrhea (OR: 0.4; 95%CI: 0.27, 0.56, p < 0.001; I2=31.3%, p = 0.178), oral mucositis (OR: 0.76; 95%CI: 0.58, 0.94, p < 0.001; I2=95.5%, p < 0.001) and severe oral mucositis (OR:0.65, 95%CI: 0.58, 0.72 p < 0.001; I2=22.1%, p = 0.274). Multi strain probiotic (OR:0.49; 95%CI: 0.32, 0.65, p < 0.001; I2=90.7%, p < 0.001) were more efficacious than single strain (OR:0.73; 95%CI: 0.66, 0.81, p < 0.001; I2=0.00%, p = 0.786). The findings of the current umbrella meta-analysis provide strong evidence that probiotic supplementation can reduce cancer complications.

Tracking the temporal dynamics of the face-like inversion effect as revealed by Chinese characters using magnetoencephalography.

The neural basis of configural processing has been extensively studied by exploiting face inversion during recognition, and growing evidence has revealed that word inversion also involves changes in configuration. However, the neural dynamics of face-like inversion effects remain unclear. Here, we tracked the temporal dynamics of neural responses that were sensitive to inversion during Chinese character recognition as they occurred during face recognition using multivariate decoding and temporal generalization analyses. We recorded magnetoencephalography while participants performed a one-back task for faces, compound characters, and simple characters with upright and inverted orientations. We showed that the inversion effect (inverted versus upright) can be decoded at occipitotemporal sensors for all stimulus types over and across time points, with a stronger impact on faces and compound characters than on simple characters. The inversion effect occurred earlier and lasted longer for faces than for characters, and the effect was also stronger for compound characters than for simple characters. Finally, we demonstrated inversion effects in the event-related field for all stimulus types and identified their sources in the ventral occipitotemporal areas. Overall, this study provides novel evidence for the temporal dynamics of the face-like inversion effect occurring during Chinese character recognition.

Focal length switchable metalens based on vanadium dioxide.

A metalens is a flat lens that can control the phase of light so that dispersed light can be reconcentrated. This study devised a tunable metalens with a switchable focal length based on the phase transition properties of vanadium dioxide (V O 2). The unit structure comprises three layers from bottom to top: gold, polyimide, and two square resonant rings. The metalens can not only transform incident x-polarized waves into y-polarized waves but also achieve beam focusing simultaneously. The designed metalens achieves polarization conversion efficiency at an operating frequency of 0.8 THz. In the insulating state of V O 2, the beam focal point is at L=1914µm; in the metallic state, the wave converges at L=982µm, closely aligning with the predetermined focal length. By controlling external temperature, focal point switching can be achieved, making it highly versatile in practical applications.

κ-Opioid receptor activation attenuates osteoarthritis synovitis by regulating macrophage polarization through the NF-κB pathway.

Osteoarthritis (OA) is a prevalent and chronic joint disease that affects the aging population, causing pain and disability. Macrophages in synovium are important mediators of synovial inflammatory activity and pathological joint pain. Previous studies have demonstrated the significant involvement of κ-opioid receptor (KOR) in the regulation of pain and inflammation. Our study reveals a significant reduction in synovial KOR expression among patients and mice with OA. Here, we find that KOR activation effectively inhibits the expressions of the LPS-induced-inflammatory cytokines TNF-α and IL-6 by inhibiting macrophage M1 phenotype. Mechanistically, KOR activation effectively suppresses the proinflammatory factor secretion of macrophages by inhibiting the translocation of NF-κB into the nucleus. Our animal experiments reveal that activation of KOR effectively alleviates knee pain and prevents synovitis progression in OA mice. Consistently, KOR administration suppresses the expressions of M1 macrophage markers and the NF-κB pathway in the synovium of the knee. Collectively, our study suggests that targeting KOR may be a viable strategy for treating OA by inhibiting synovitis and improving joint pain in affected patients.

Mortality Study of Patients with Omicron Infection Before and After the Implementation of the New Crown Standard.

Objective: To investigate the mortality rate of patients with Omicron infection before and after the implementation of the new crown standard, and to evaluate the impact of new treatment protocols on the mortality rate of patients with Omicron infection. Methods: Clinical data of 1419 Omicron-infected patients treated in our hospital from April 10, 2022 to June 3, 2022 were collected(Patients diagnosed with Omicron infection who met the diagnostic criteria in the "Diagnosis and treatment protocol for novel coronavirus pneumonia (trial version 9)"15 and whose nasal/pharyngeal swab samples were typed as Omicron variants by laboratory viral genotyping). They were divided into the observation group (April 25 2022 - June 3 2022) and the control group (April 10 2022 - April 24 2022) before and after the implementation criteria. Clinical data of 1419 patients were collected and compared between the two groups on whether to use anticoagulant drugs, whether to use antiplatelet drugs, gender, whether to use new drugs of thymosin/thymus method, age, whether to use herbal medicine, whether to use Fuzheng prescription, blood routine, liver function, kidney function indicators, mortality of patients. Results: A total of 1419 patients were initially selected; 501 patients with incomplete information were excluded, and finally, 918 patients were included. According to the time period before and after the application criteria, they were divided into an observation group (586 cases) and a control group (332 cases). There were no statistically significant differences in gender, age, antiplatelet drug use, and herbal medicine use between the two groups (P < .05). However, there were significant differences in the use of anticoagulant drugs, thymidine/thymidine drugs, and Fu Zhengfang between the two groups. It was statistically significant that the mortality rate in the observation group (2.39)% was significantly lower than that in the control group (5.12)%. P < .05 White blood cell count, red blood cell ratio, lymphocyte count, hemoglobin, neutrophil count, and neutrophil ratio were not significantly different between the two groups (P < .05) .In comparison to the control group (4.92±8.00)10^9/L, the platelet count in the observation group (4.77±3.41)109/L was considerably lower. The difference was statistically significant (P < .05). The comparison of total bilirubin, total protein values and alkaline phosphatase values between the two groups was not significant (P < .05). In the observation group, albumin (38.71±6.39) g/L, glutamate transaminase (23.93±26.03) U/L, glutathione transaminase (26.12±25.53) U/L, gamma-glutamyltransferase (34.28±52.3) U/L, globulin values (28.13±5.55) g/L were significantly lower than those of the control group (36.66±7.08) g/L, (30.36±65.77) U/L, (33.29±49.72) U/L, (43.76±80.23) U/L, (29.85±5.67) g/L, the difference was statistically significant (P < .05). Between the two groups, there were no significant differences in the values of uric acid or creatinine (P > .05). Levels and uric acid readings did not differ significantly, P > .05. The difference between the urea values of the observation group (7.44±6.34 mmol/L) and the control group (8.75±7.51 mmol/L) was statistically significant (P < .05). Conclusion: After the implementation of the treatment protocol for COVID-19 (Trial Version 9), the number of death cases among patients with Omicron variant infection has significantly decreased. The treatment protocol is safe and feasible and can be widely applied in clinical settings..And it will further promote the development and administration of vaccines to prevent and control the spread of the novel coronavirus, reducing the occurrence of patients and death cases.

PKM2 is a Novel Osteoporosis-Associated Protein in Chinese.

Purpose:Osteoporosis is characterized by low bone mineral density (BMD) and high risk of osteoporotic fracture (OF). Peripheral blood monocytes (PBM) can differentiate into osteoclasts to resorb bone. This study was to identify PBM-expressed proteins significant for osteoporosis in Chinese Han elderly population (>65 years), and focused on two phenotypes of osteoporosis: low BMD and OF. METHODS: Label-free quantitative proteomics was employed to profile PBM proteome and to identify differentially expressed proteins (DEPs) between OF (N=27) vs. non-fractured (NF, N=24) subjects and between low BMD (N=12) vs. high BMD (N=12) subjects in women. Western blotting (WB) was conducted to validate differential expression, and ELISA to evaluate translational value for secretory protein of interest. RESULTS: We discovered 59 DEPs with fold change (FC)>1.3 (P<1×10-5), and validated the significant up-regulation of pyruvate kinase isozyme 2 (PKM2) with osteoporosis (P<0.001). PKM2 protein upregulation with OF was replicated with PBM in men (P=0.04). Plasma PKM2 protein level was significantly elevated with OF in an independent sample (N=100, FC=1.68, P=0.01). Pursuant functional assays showed that extracellular PKM2 protein supplement not only promoted monocyte trans-endothelial migration, growth, and osteoclast differentiation (marker gene expression), but also inhibited osteoblast growth, differentiation (ALP gene expression), and activity. CONCLUSION: The above findings suggest that PKM2 protein is a novel osteoporosis-associated functional protein in Chinese Han elderly population. It may serve as a risk biomarker and drug target for osteoporosis.

cis-Regulatory variation affecting gene expression contributes to the improvement of maize kernel size.

cis-Regulatory variations contribute to trait evolution and adaptation during crop domestication and improvement. As the most important harvested organ in maize (Zea mays L.), kernel size has undergone intensive selection for size. However, the associations between maize kernel size and cis-regulatory variations remain unclear. We chose two independent association populations to dissect the genetic architecture of maize kernel size together with transcriptomic and genotypic data. The resulting phenotypes reflected a strong influence of population structure on kernel size. Compared with genome-wide association studies (GWASs), which accounted for population structure and relatedness, GWAS based on a naïve or simple linear model revealed additional associated single-nucleotide polymorphisms significantly involved in the conserved pathways controlling seed size in plants. Regulation analyses through expression quantitative trait locus mapping revealed that cis-regulatory variations likely control kernel size by fine-tuning the expression of proximal genes, among which ZmKL1 (GRMZM2G098305) was transgenically validated. We also proved that the pyramiding of the favorable cis-regulatory variations has contributed to the improvement of maize kernel size. Collectively, our results demonstrate that cis-regulatory variations, together with their regulatory genes, provide excellent targets for future maize improvement.

Temporal expectation based on the duration variability modulates alpha oscillations during working memory retention.

While maintaining information over a delay of time, working memory (WM) also allows individuals to prepare the mnemonic contents for prospective utilisation. However, it remains unclear whether the expectation of the time of WM test could modulate neural responses during the retention interval of WM and subsequent performance. Here, we investigated whether temporal expectations based on the variability of delay duration can modulate 9-13 Hz alpha oscillations during WM retention and whether the expectation-induced alpha activity was associated with WM performance. Participants performed a retro-cueing WM task with magnetoencephalography (MEG) (Experiment 1) and a standard WM task with electroencephalography (EEG) (Experiment 2). The expectation of the timing of the WM test was manipulated by the temporal structure of the tasks with small or large variability in the delay durations. We showed that alpha oscillations during retention interval and WM performance varied with duration variability in both of the MEG and EEG experiments. The novel finding was greater alpha-power attenuation over the left frontal and parietal regions during WM retention when the duration variability was small and the test onset was predictable, compared to when the duration variability was large and the test onset was less predictable. Importantly, we observed a positive relationship in variability difference between the response benefit and alpha-power attenuation in the left posterior parietal regions at both MEG-source and EEG-electrode levels. Finally, we confirmed the behavioural benefit when a condition with a fixed delay-duration was included in a behavioural experiment (Experiment 3). When conjoined, the delay duration enables individuals to anticipate when the relevant information would be put to work, and alpha oscillations track the anticipatory states during WM maintenance.

A novel two-step administration of XPO-1 inhibitor may enhance the effect of anti-BCMA CAR-T in relapsed/refractory extramedullary multiple myeloma.

BACKGROUND: Extramedullary disease usually implies a dismal outcome in relapsed/refractory multiple myeloma patients, and requires novel treatment approaches. We designed a trial using Selinexor, a nuclear export protein 1 inhibitor, together with anti-B cell maturation antigen (BCMA) chimeric antigen receptor (CAR)-T cell product CT103A to treat these patients, and describe the first two cases in this report. METHODS: Selinexor was administered with a novel two-step schedule in bridging therapy and in maintenance. The clinical responses and adverse events were recorded after CAR-T infusion and Selinexor administration. In vitro analysis of the influence of Selinexor on CAR-T cell function was performed using myeloma cell lines. RESULTS: After infusion, both patients achieved stringent complete remission (sCR), and were maintained in sCR at data-cutoff, with survival over 13 and 10 months, respectively. Neither immune effector cell-associated neurotoxicity syndrome nor over grade 2 cytokine release syndrome was observed. Meanwhile, the patients showed good tolerance to the combination. In addition, we demonstrated that low dose of Selinexor could upregulate the expression of BCMA on plasma cell lines and subsequently enhance the function of CAR-T cell in vitro. CONCLUSIONS: The combination of Selinexor and CT103A exerts preliminary synergistic effect, and can be developed as a promising strategy for relapsed/refractory extramedullary myeloma.

Genomic insight into changes of root architecture under drought stress in maize.

Drought stress is a central environmental factor that severely limits maize production worldwide. Root architecture plays an important role in drought tolerance and can be targeted in breeding programmes. Here, we conducted phenotyping of root architecture under different water treatments for 373 maize inbred lines, representative germplasm from both China and the United States in different breeding eras. We found that seminal root length in response to drought stress experienced convergent increase during breeding in both countries. Using a genome-wide association study, we identified a total of 221 associated loci underlying 13 root traits under well-watered and water-stressed conditions. These loci harboured many reported root- and abiotic stress-related genes. Furthermore, a total of 75 strong candidate genes were prioritised by integrating candidate genes associated with seminal root length and differentially expressed genes in seminal root. One of high-confidence candidate genes, ZmCIPK3 was functionally characterised and probably plays a role in enhancing drought tolerance through regulating seminal root growth. This study provides valuable information for genetic improvement of root architecture and drought tolerance in maize.

Development of an intraoral handheld optical coherence tomography-based angiography probe for multi-site oral imaging.

Oral cancer, primarily oral squamous cell carcinomas (OSCC), is a major health concern worldwide. The current gold standard for the diagnosis of OSCC is biopsy and histopathological analysis, which is invasive and can place a huge financial burden on the healthcare system. Optical coherence tomography-based angiography (OCTA) is a non-invasive imaging technique that shows promise as an imaging modality to aid the diagnosis of OSCC. This Letter outlines the development of a handheld intraoral OCT probe applied to a swept-source OCT system with an angiography function for oral applications. The probe has a thin body with a diameter of 17.8 mm and a two-lens system with a working distance that is adjustable from 20.92 mm to 24.08 mm, a field of view 9 mm in diameter, an imaging depth of ∼1.7 mm, and resolutions of 39.38 µm (laterally) and 33.37 µm (axially). This probe was used to scan 14 oral sites to evaluate its ability to scan various sites in the oral cavity. This system has the potential to reduce invasive procedures and aid early OSCC diagnosis.

The exploration of B cell maturation antigen expression in plasma cell dyscrasias beyond multiple myeloma.

BACKGROUND: B cell maturation antigen (BCMA) targeted immunotherapies have demonstrated remarkable clinical efficacy in multiple myeloma (MM). Here, we evaluated the BCMA expression in MM and other plasma cell dyscrasias (PCDs), hoping to provide a potential treatment strategy for the relapsed/refractory PCDs besides MM. METHODS: From January 2018 to August 2021, 377 patients with PCDs were enrolled in this study, including 334 MM, 21 systemic light chain amyloidosis (AL), 5 POEMS syndrome, 14 monoclonal gammopathy of undetermined significance (MGUS), and three monoclonal gammopathy of renal significance (MGRS). The membrane-bound BCMA expression measured by multiparameter flow cytometry was defined by BCMA positivity rate and the mean fluorescence intensity (MFI). RESULTS: The patients with MM had a median BCMA positive rate of 88.55% (range, 0.2% - 99.9%) and median BCMA MFI of 1281 (range, 109 - 48586). While the median BCMA positive rate in other PCDs was 55.8% (6.2% -98.9%), and the median BCMA MFI was 553 (182- 5930). BCMA expression level was negatively associated with hemoglobin concentration in multivariate analysis in terms of BCMA positive rate and MFI. CONCLUSIONS: In conclusion, BCMA has the potential to be a therapeutic target for other PCDs besides MM.

Rapid Prediction of a Liquid Structure from a Single Molecular Configuration Using Deep Learning.

Molecular dynamics simulation is an indispensable tool for understanding the collective behavior of atoms and molecules and the phases they form. Statistical mechanics provides accurate routes for predicting macroscopic properties as time-averages over visited molecular configurations - microstates. However, to obtain convergence, we need a sufficiently long record of visited microstates, which translates to the high-computational cost of the molecular simulations. In this work, we show how to use a point cloud-based deep learning strategy to rapidly predict the structural properties of liquids from a single molecular configuration. We tested our approach using three homogeneous liquids with progressively more complex entities and interactions: Ar, NO, and H2O under varying pressure and temperature conditions within the liquid state domain. Our deep neural network architecture allows rapid insight into the liquid structure, here probed by the radial distribution function, and can be used with molecular/atomistic configurations generated by either simulation, first-principle, or experimental methods.

Mutations in immunodeficiency-related genes may increase the risk of infection after CAR-T-cell therapy: a report of two cases.

BACKGROUND: Chimeric antigen receptor T-cell therapy (CAR-T) has yielded unprecedented efficacy in B-cell malignancies. With the increasing use of CAR-T-cell therapy, infection has become one of the major concerns after CAR-T-cell infusion. Some patients even develop refractory or recurrent infections, posing challenges in treatment, prophylactic, and monitoring strategies. However, the mechanisms underlying the development of these infections were not clear. CASE PRESENTATION: We report two cases of infection after CAR-T-cell therapy. Patient 1, diagnosed with multiple myeloma, received anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T (CAR-T)-cell therapy. He developed a refractory urinary infection lasting for over 5 weeks, which was caused by Candida albicans. Whole-exome sequencing revealed that he had an IL-17RA gene mutation. Patient 2, diagnosed with acute lymphoblastic B-cell leukaemia, received anti-CD19 and anti-CD22 CAR-T-cell cocktail therapy and remained in complete remission for over 4 years. The patient had pneumonia five times during the 4 years. Whole-exon sequencing revealed that he had a CX3CR1 gene mutation. CONCLUSION: For patients who develop persistent or recurrent infections after CAR-T-cell therapy, it is recommended to screen for immunodeficiency-related gene mutations, and the results may contribute to the management of infections post-CAR-T treatment.

Overexpression of ZmEXPA5 reduces anthesis-silking interval and increases grain yield under drought and well-watered conditions in maize.

Drought is one of the major abiotic stresses affecting the maize production worldwide. As a cross-pollination crop, maize is sensitive to water stress at flowering stage. Drought at this stage leads to asynchronous development of male and female flower organ and increased interval between anthesis and silking, which finally causes failure of pollination and grain yield loss. In the present study, the expansin gene ZmEXPA5 was cloned and its function in drought tolerance was characterized. An indel variant in promoter of ZmEXPA5 is significantly associated with natural variation in drought-induced anthesis-silking interval. The drought susceptible haplotypes showed lower expression level of ZmEXPA5 than tolerant haplotypes and lost the cis-regulatory activity of ZmDOF29. Increasing ZmEXPA5 expression in transgenic maize decreases anthesis-silking interval and improves grain yield under both drought and well-watered environments. In addition, the expression pattern of ZmEXPA5 was analyzed. These findings provide insights into the genetic basis of drought tolerance and a promising gene for drought improvement in maize breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01432-x.

Significantly improved thermoelectric performance of SnSe originating from collaborative adjustment between valence and conduction bands, mass fluctuations, and local strain.

In this study, environmentally friendly, low cost, and easy to synthesize InSn and VSn co-doped SnSe materials was designed and prepared via vacuum melting and spark plasma sintering technology, which avoids the shortcomings of high-performance Pb, Ge, and Na-doped SnSe samples. InSn and VSn, doping achieved appropriate bandgap (Eg) and energy band degeneracy (NV) from the valence and conduction band, obtaining the highest electrical conductivity of 4726 S m-1 at 773 K. The impurity state controls the carrier transport process below 573 K, while Eg and NV control the process above 573 K. InSn and VSn doping induces quality fluctuation and local strain, which decreases the lattice thermal conductivity. Owing to the higher power factor and low lattice thermal conductivity, the ZT value of the Sn0.985In0.01Se sample was 1.3 at 773 K. Dual regulation of the valence and conduction band provides a new idea for adjusting the transport behavior of semiconductors.

ORF355 confers enhanced salinity stress adaptability to S-type cytoplasmic male sterility maize by modulating the mitochondrial metabolic homeostasis.

Moderate stimuli in mitochondria improve wide-ranging stress adaptability in animals, but whether mitochondria play similar roles in plants is largely unknown. Here, we report the enhanced stress adaptability of S-type cytoplasmic male sterility (CMS-S) maize and its association with mild expression of sterilizing gene ORF355. A CMS-S maize line exhibited superior growth potential and higher yield than those of the near-isogenic N-type line in saline fields. Moderate expression of ORF355 induced the accumulation of reactive oxygen species and activated the cellular antioxidative defense system. This adaptive response was mediated by elevation of the nicotinamide adenine dinucleotide concentration and associated metabolic homeostasis. Metabolome analysis revealed broad metabolic changes in CMS-S lines, even in the absence of salinity stress. Metabolic products associated with amino acid metabolism and galactose metabolism were substantially changed, which underpinned the alteration of the antioxidative defense system in CMS-S plants. The results reveal the ORF355-mediated superior stress adaptability in CMS-S maize and might provide an important route to developing salt-tolerant maize varieties.

Source and migration patterns of heavy metals and human health risk assessment of heavy metals in soil-corn straw-flue gas system.

The process of rapid urbanization in Northeast China has resulted in severe heavy metal pollution in the environment. In this study, we investigated the characteristics of heavy metal pollution in soil-corn straw and its combustion flue gas system, and the health risks of heavy metal pollution. The results showed that Cu and Zn in soil were more easily absorbed by corn straw roots. Heavy metals in soil, corn straw and flue gas from corn straw burning all pose some health risk to humans, and are more harmful to children than adults. The concentrations of heavy metals in both soil and flue gas from corn straw burning have reached extremely high ecological risk. The main sources of heavy metal elements in soils are, in order, industrial production, agricultural production activities and metallurgical production. This study highlights the key issues of heavy metal contamination in soil-corn straw and its combustion flue gas system, provides an auxiliary guide for the next step in analyzing the transfer mechanisms, and suggests a rational approach to mitigate heavy metal contamination.

Study on metal elements in indoor particulate matter: a case study of rural residential environment in Northeast China.

The use of solid fuels for heating and cooking in rural Northeast China has led to severe indoor metal element pollution in particulate matter (PM), posing a direct threat to human health and creating immense pressure on the sustainability of residential environments. To investigate the levels, sources, and potential health hazards of indoor metal element pollution in this region, we conducted a year-long sampling and monitoring campaign in actual residential settings and used ICP-OES to measure six metal elements (Mn, Cr, Zn, Cu, Pb, and Ni). This study's findings reveal that indoor metal element pollution levels in PM (33,513.65 mg/kg per year) are higher in rural Northeast China compared to other rural areas. Straw burning is the primary source of metal element pollution, followed by motor vehicle emissions and natural soil sources. It is crucial to note that our results indicate a total carcinogenic risk greater than 10-4 according to the US EPA health risk model assessment, highlighting the high risk posed to human health by indoor metal elements in rural areas. By using a seriously polluted area in Northeast China as a case study, this research provides initial insights into the characteristics and sources of indoor metal pollution in rural areas, offering a reference for future prevention and control of indoor pollution in these regions. Ultimately, this work can help improve the rural habitat and enhance the health of the rural population.