Abstract: Radiation therapy is an important treatment for malignant tumors. Although it can effectively kill tumor cells, it also causes ionizing radiation (IR) damage to normal tissues, resulting in a variety of acute and chronic adverse reactions. Currently, there are significant limitations in the efficacy, targeting, and safety of clinically available radioprotective drugs, and there is an urgent need for the development of new, more efficient and safer protection strategies. Extracellular vesicles (EVs), as natural nanocarriers, are capable of delivering functional molecules and participating in various processes, such as DNA repair, alleviation of oxidative stress, modulation of apoptosis, and immune microenvironment, which have demonstrated a wide range of potentials for the alleviation of IR-associated tissue damage. Numerous studies have shown that mesenchymal stem cell-derived EVs (MSC-EVs), immune cell-derived EVs, and engineered EVs are effective in attenuating IR-induced tissue damage in various animal models. In this paper, we systematically reviewed the multiple mechanisms of EVs-mediated radioprotection, sorted out their main sources and biological properties, and focused on the optimization strategy of their engineering and the challenges of their clinical applications, with the aim of providing a theoretical basis and research references for the development and translation of EVs as a novel means of radioprotection.
Key words: extracellular vesicles; radioprotection; MSC-EVs; DNA repair; oxidative stress
（Acta Laser Biology Sinica, 2026, 35(1): 001-009）

Abstract: In breast cancer radiotherapy, exposure of the heart and its substructures to radiation is one of the important risk factors for long-term cardiovascular diseases, which is particularly prominent in patients with left-sided breast cancer. The deep inspiration breath hold (DIBH) technique is an effective method to reduce cardiac radiation dose by having the patient take a deep breath and hold it, thereby moving the heart away from the target area. This article systematically reviews the principles, dosimetric advantages of the DIBH technique, and its application effects when combined with different radiotherapy techniques involving three-dimensional conformal radiation therapy (3DCRT), intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and proton therapy technology. Studies have shown that the DIBH technique can significantly reduce the mean heart dose (MHD) and the doses to substructures such as the left anterior descending artery (LAD) and left ventricle (LV). Among them, it is found that DIBH combined with 3DCRT or proton therapy technology has the best cardioprotective effect. While when combining IMRT and VMAT with DIBH, further consideration of target dose uniformity and cardiac dose is needed to select the optimal method. In addition, regarding the correlation between cardiac substructure doses and the risk of cardiovascular events, it is necessary to combine relevant factors such as anatomical characteristics, biomarkers, and dose parameters to construct an individualized risk prediction model. In the future, we should focus on technical optimization, patient selection, and multimodal image guidance. Through these measures, maximizing the use of the DIBH technique will enable us to minimize radiotherapy-related cardiac toxicity.
Key words: breast cancer; radiation therapy; deep inspiration breath hold; cardiac protection; dosimetry
（Acta Laser Biology Sinica, 2026, 35(1): 010-018）

Abstract: To investigate the early radiochemical processes of γ-ray-induced DNA single-strand breaks (SSB), this study employed the Monte Carlo simulation tool TOPAS and its extended module TOPAS-nBio to construct a water sphere-plasmid microscale simulation model. The model was used to simulate the irradiation of supercoiled pUC19 plasmids by 60Coγ-rays in an aqueous environment and the subsequent induction of SSB in plasmid DNA. The study quantitatively compared the SSB yield under systematically varied conditions of radiation dose, DNA concentration, and hydroxyl radical (·OH) scavenger concentration. The simulation results showed that the SSB yield increased with the elevation of radiation dose. A higher DNA concentration in the environment led to an approximately linear increase in the absolute SSB yield, while the damage efficiency per unit mass of DNA decreased with increasing concentration. An increase in the concentration of ·OH scavengers significantly reduced the SSB yield, indicating that the ·OH scavenging capacity exerts a marked inhibitory effect on SSB formation. The findings of this study provide certain theoretical support for the optimization of radiotherapy, the formulation of radiation protection strategies, and the health risk assessment of nuclear environments.
Key words: gamma ray; plasmid DNA; free radical; Monte Carlo simulation; DNA single strand break
（Acta Laser Biology Sinica, 2026, 35(1): 028-034）

Abstract: Although diet and gut microbial composition have been linked to chronic respiratory diseases, these associations remain difficult to interpret because of confounding and reverse causation. The gut-lung axis provides a plausible framework for this interaction, yet direct genetic evidence is limited. Using a two-step, two-sample Mendelian randomization (MR) framework, supplemented by multivariable MR (MVMR) to adjust for pleiotropic effects and Benjamini-Hochberg false discovery rate (FDR) correction for multiple testing, we assessed the causal contributions of dietary habits and gut microbial taxa to major chronic respiratory diseases. We identified 22 dietary factors with causal effects on disease risk and 225 microbial taxa that acted as independent risk or protective contributors. Mediation analyses further showed that the effects of 12 dietary habits were transmitted through 32 specific microbial taxa. Notably, genetically predicted pork intake increased the risk of chronic obstructive pulmonary disease (COPD) (OR=10.53, 95% CI [8.54, 13.00]), an effect partly mediated by elevated abundance of CAG-485 sp002404675. In contrast, bread consumption conferred protection against asthma (OR=0.68, 95% CI [0.64, 0.72]), whereas this benefit was offset by approximately 45% through a pathway involving reduced Veillonella abundance. Collectively, these findings provide genetic support for the gut-lung axis and demonstrate that the gut microbiome functions as a causal mediator linking diet to chronic respiratory disease risk. However, since this study was based on individuals of European ancestry, caution is warranted when generalizing these causal estimates to non-European populations, such as East Asian groups. This work suggests new opportunities for microbiota-targeted prevention and therapeutic strategies.
Key words: Mendelian randomization; gut microbiome; respiratory disease; dietary; European descent populations
CLC number: R56                 Document code: A        DOI: 10.3969/j. issn.1007-7146.2026.01.005

Abstract: To identify the pathogen and its taxonomic status causing a new leaf spot disease in the Yongzhou tobacco-growing area of Hunan Province, and to screen effective control agents through laboratory toxicity assays, in this study, tobacco leaves were collected from the tobacco-growing regions of Yongzhou. The pathogen was isolated via tissue culture, single-spore isolation, and purification. Pathogenicity was confirmed through in vitro inoculation. The pathogen was identified by PCR amplification and sequencing of the ITS region, followed by phylogenetic analysis, combined with morphological characterization of colonies and spores. The indoor toxicity of nine fungicides, including 43% Fluopyram·Trifloxystrobin (SC), against the pathogen was determined using the mycelial growth rate method. Laboratory toxicity tests indicated that 43% Fluopyram‌·Trifloxystrobin (SC), 70% Thiophanate-methyl (WP), and 42.4% Pyraclostrobin·Fluopyram (SC) exhibited the strongest inhibitory effects against Corynespora. cassiicola, with EC50 values of 3.028 5 mg/L, 5.148 0 mg/L, and 8.787 9 mg/L, respectively. Moderately effective fungicides included 70% Mancozeb (WP), 75% Trifloxystrobin·Tebuconazole (WG), 32.5% Benzovindiflupyr·Azoxystrobin (SC), and 38% Pyraclostrobin·Boscalid (WG), with EC50 values of 21.844 3 mg/L, 31.841 8 mg/L, 32.080 1 mg/L, and 41.867 6 mg/L, respectively. The least effective agents were 40% Mefentrifluconazole·Pyraclostrobin (SC) and 75% Chlorothalonil (WP), with EC50 values of 192.466 9 mg/L and 1 341.062 0 mg/L, respectively. This study revealed that the new leaf spot disease on tobacco in Yongzhou was caused by C. cassiicola. C. cassiicola was identified as the causal agent of Corynespora leaf spot disease in tobacco. Strobilurin and benzimidazole fungicides showed superior inhibitory efficacy. The findings provide a scientific basis for the effective local control of tobacco Corynespora leaf spot disease.
Key words: tobacco; Corynespora leaf spot disease; Corynespora cassiicola; indoor virulence assay; fungicide
（Acta Laser Biology Sinica, 2026, 35(1): 053-061）

Abstract: Sowing date is a critical factor affecting the growth and yield of millet, and its optimal management is essential for maximizing productivity. In this study, the effects of sowing date on the growth and yield of foxtail millet were investigated through field experiments combined with APSIM-Millet model simulations. Using historical meteorological data (1984—2023), we further explored strategies for optimizing sowing date management. The APSIM-Millet model accurately simulated the growth process of foxtail millet across different sowing dates and varieties. Historical simulation revealed that the optimal sowing date for millet in Shanxi Province was gradually delayed from north to south, with additional variations due to irrigation conditions. For the late-maturing variety Jingu 21, the best rain-fed sowing window ranged from March 30 to April 19 in northern Datong City, shifting southward to May 21 to June 10 in the southernmost Yuncheng City. Under irrigation conditions, the optimal sowing date was 20～30 days later than under rain-fed conditions. In contrast, the early-maturing millet variety Tonggu 30 exhibited a later optimum sowing date than Jingu 21, with a 70-day north-south span. Irrigation further aggravated regional differences. These findings highlight the close relationship between sowing date responsiveness and regional water/heat resource distribution. In cold northern regions, early sowing helps avoid later-season drought, while the warm and humid southern areas benefit from delaying sowing to optimize light and temperature utilization. Integrating field experiment results, the rain-fed early sowing mode was preferred in arid northern Shanxi, and gradient sowing being adjusted to irrigation availability in the warmer southern Shanxi, and climate-resource efficiency was realized through varietal adaptations, e.g. , limited southward extension the late maturing variety Jingu 21 and enhanced north-south sowing differentiation for the early maturing variety Tonggu 30. This study provides a theoretical foundation for optimizing regional sowing dates in Shanxi’s millet production systems.
Key words: millet; variety; sowing date; APSIM-Millet model; yield
（Acta Laser Biology Sinica, 2026, 35(1): 062-071）

Abstract: Hearing loss is a widespread global health issue that affects all regions and countries. It is classified into conductive hearing loss, sensorineural hearing loss, and mixed hearing loss. Oxidative stress and redox homeostasis imbalance are important factors causing cochlear damage, and NRF2 is a crucial antioxidant regulatory factor. In the human body, the Nfe2l2 gene is widely expressed in the central nervous system, auditory organs, and metabolism-related organs and tissues, playing a significant role in maintaining cellular redox homeostasis, responding to oxidative stress, and regulating metabolism, inflammation, autophagy, and immune responses. In noise exposure experiments, Nrf2-KO mice showed more severe hearing impairment compared to wild-type mice. In zebrafish, nrf2a is widely expressed in the early stages of embryonic development and acts as a core transcription factor to regulate the expression of a series of antioxidant genes, constituting an important defense mechanism against exogenous oxidative damage from chemicals and heavy metals. Besides its antioxidant function, this gene is crucial for the development and homeostasis maintenance of various organs in zebrafish, such as the liver and nervous system, and plays an important protective role in regulating inflammatory responses, metabolic processes, and inhibiting apoptosis. To study the specific mechanism of this gene in the development of inner ear and lateral line hair cells, a zebrafish nrf2a gene knockout line was constructed using CRISPR/Cas9 gene editing technology. First, online analysis tools were used to screen the knockout target sites of the nrf2a gene, and the guide DNA of this gene was amplified and synthesized by polymerase chain reaction. This was then used as a template for transcription, and the transcribed sgRNA was mixed with Cas9 protein at a ratio of 5: 1 and injected into 1-cell stage zebrafish embryos. Subsequently, the effectiveness of the gene knockout was verified. The results showed that there was a large fragment deletion in the nrf2a gene, and translation was prematurely terminated, indicating successful knockout of the gene. After screening, a homozygous mutant of the nrf2a gene was obtained, laying the foundation for studying the role of this gene in the development of inner ear and lateral line hair cells.
Key words: zebrafish; CRISPR/Cas9; nrf2a gene; hearing loss; inner ear development
（Acta Laser Biology Sinica, 2026, 35(1): 072-080）

Abstract: To investigate the expression of circular RNA (circRNA) circKRT75 in tongue squamous cell carcinoma (TSCC) tissues and the effects of silencing its expression on the proliferation and invasion of TSCC cells. The cBioPortal database was used to analyze the expression of circKRT75 in TSCC tissues and the correlation between circKRT75 expression and survival in TSCC patients. Quantitative real-time polymerase chain reaction (qPCR) was used to detect circKRT75 expression in TSCC cell lines H357, Tca8113, TSCCA, HN13, and SCC-9. si-circKRT75 and control plasmids were transfected into H357 cells using lipofectamine, defining them as the si-circKRT75 and si-NC groups, respectively. The effects of low-expression circKRT75 on the proliferation and invasion of H357 cells were assessed by MTT and Transwell assays, respectively. Western blot analysis was used to examine the effects of low-expression circKRT75 on the expression of Cyclin E and Cyclin-dependent kinase 2 (CDK2), matrix metalloproteinase-2 (MMP-2) and Alpha-smooth muscle actin (α-SMA) in H357 cells. Dual-luciferase reporter assays were used to validate the targeting relationship between circKRT75 and miR-128-3p. The cBioPortal database was used to analyze the correlation between the expression of circKRT75 and miR-128-3p in TSCC tissues. qPCR was used to detect the effect of low-expression circKRT75 on miR-128-3p expression. circKRT75 expression was higher in TSCC tissues than in normal oral mucosa tissues (P<0.01). circKRT75 expression was negatively correlated with TSCC patient survival (P<0.01). Compared with normal human oral keratinocytes (HOK) cells, circKRT75 expression was higher in TSCC cell lines H357, Tca8113, TSCCA, HN13, and SCC-9 (all P<0.05). Compared with the si-NC group, low circKRT75 expression inhibited the proliferation (P<0.05) and invasion (P<0.01) of H357 cells. Low circKRT75 expression downregulated the expression of Cyclin E, CDK2, MMP-2, and α-SMA proteins in H357 cells (all P<0.01). circKRT75 had a targeting relationship with miR-128-3p (P<0.01). The expression of circKRT75 in TSCC tissues was negatively correlated with the expression of miR-128-3p (P<0.01). Compared with the si-NC group, low expression of circKRT75 upregulated miR-128-3p expression (P<0.01). circKRT75 is highly expressed in TSCC tissues and cell lines, and low expression of circKRT75 inhibits the proliferation and invasion of TSCC cells by regulating miR-128-3p expression. circKRT75 may become a molecular therapeutic target for TSCC.
Key words: circular RNA; tongue squamous cell carcinoma; microRNA; cell proliferation; cell migration
（Acta Laser Biology Sinica, 2026, 35(1): 081-087）

Abstract: Acupoint application combined with Modified Bazhen Decoction mediated the effect of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway on bone marrow hematopoietic function in mice with bone marrow inhibition. The BALB/c mice were randomly divided into control group, model group, acupoint application group, Modified Bazhen Decoction group, and combined drug group, with 10 mice in each group. Tail vein blood was collected to measure the levels of hemoglobin, white blood cells, and platelets in peripheral blood. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of serum erythropoietin (EPO), thrombopoietin (TPO) and granulo-monocyte colony-stimulating factor (GM-CSF). Bone marrow nucleated cell counts were performed in each group of rats. For the myeloid nucleated cells of each group, colony forming unit-granulocyte and macrophage (CFU-GM), colony forming unit-erythrocyte (CFU-E) and colony forming unit-megakaryocyte, erythrocyte and granulocyte (CFU-Meg) were detected. The kit was used to detect the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in serum. The expression of p-JAK1, JAK1, p-JAK2, JAK2, p-STAT3, STAT3 proteins in mouse nucleated bone marrow cells were detected by Western blot. The results showed that compared with the control group, the number of hemoglobin, leukocytes, platelets, EPO, TPO, GM-CSF, SOD, bone marrow nucleated cells and the number of cell colonies of hematopoietic progenitor cells CFU-GM, CFU-E and CFU-Meg in the model group decreased (P<0.05), and the MDA, p-JAK1/JAK1, p-JAK2/JAK2, p-STAT3/STAT3 increased (P<0.05). Compared with the model group, the number of hemoglobin, leukocytes, platelets, EPO, TPO, GM-CSF, SOD, bone marrow nucleated cells and the number of cell colonies of hematopoietic progenitor cells CFU-GM, CFU-E and CFU-Meg increased in the acupuncture point application group, Modified Bazhen Decoction group and combined drug group (P<0.05), and the MDA, p-JAK1/JAK1, p-JAK2/JAK2, p-STAT3/STAT3 decreased (P<0.05). Acupoint application and Modified Bazhen Decoction could synergize (P<0.05). It indicated that acupoint application combined with Modified Bazhen Decoction synergistically improves the bone marrow hematopoietic function of mice with bone marrow suppression by reducing oxidative stress, and its mechanism may be related to the inhibition of JAK/STAT signaling pathway.
Key words: acupoint application; Modified Bazhen Decoction; bone marrow inhibition; Janus kinase/signal transducer and activator of transcription signaling pathway; oxidative stress
（Acta Laser Biology Sinica, 2026, 35(1): 088-096）