Key words: photobiomodulation; Alzheimer’s disease; near-infrared light; advanced therapy methods; medical device

（Acta Laser Biology Sinica, 2024, 33(1): 001-013）

Abstract: Plastics were invented a century ago and utilized by human being ever since, which bring tremendous convenience to our daily life. Plastic products and constituents can break down into microplastics (MPs) while undergoing combined physical, chemical, and biological processes. MPs in the environments might enter into the drinking water. Such contamination and potential health risks gradually become concerns. The qualitative and quantitative detection of MPs is still in its developmental stage. Raman spectroscopy (RS) is one of the commonly used sensitive, non-invasive and non-destructive optical methods in MPs analysis. This article primarily focuses on the sources, potential hazards of MPs in drinking water, and research advancements in RS technology, in order to promote better understanding of MPs contamination and drawattention to the research and development of MPs detection technology.

Key words: microplastics; drinking water; hazards; Raman spectroscopy; detection

（Acta Laser Biology Sinica, 2024, 33(1): 014-023）

Abstract: Myopia, as the most common disease in ophthalmology, has developed into a serious international public health burden, the development situation is not optimistic. It is necessary to put forward new and effective intervention measures to curb the prevalence of myopia. In recent years, red light intervention to delay the progress of myopia has become a new research hotspot. Starting with the epidemic situation and inducement of myopia, this paper briefly introduces the commonly used clinical treatment methods, summarizes the research status of red light intervention in myopia, and discusses the possible mechanism of red light intervention in improving myopia. Some potential laser safety problems are put forward, hoping to provide reference for related research in the future.

Key words: myopia; red light; photobiological regulation; security; adolescence

（Acta Laser Biology Sinica, 2024, 33(1): 024-030）

Abstract: Koi is a brightly coloured, elegant fish with high ornamental value, and is known as a “swimming work of art”. Fish body colour is mainly determined by the type and distribution of pigment cells on the skin or scales. In this paper, the composition, distribution and morphology of pigment cells in the scales and skin of four different body colours, namely, black, white, yellow and red koi, were compared. The composition of pigment cells in the scales and skin was consistent, and rich iridescent cells were present in all four koi, with melanophores in black koi, and xanthophores and erythrophores in yellow and red koi. Only iridophores were observed in white koi. The ultrastructure of iridophores in all four koi colours was observed by transmission microscopy, and the iridophores mainly had three different morphologies: pike-shaped, short rod-shaped and vacuolated. Real-time fluorescence quantitative PCR was used to detect the expression of eight iridocyte development-related genes in the skin of four different body colors of koi carp, the results showed that eight genes related to iridophores development were expressed in the skin of different body colours, whereas there were differences in expression, among which the relative expression of alk, pka, sox10, pax3, foxd3 and pnp4a genes was higher in red and yellow koi, while the relative expression of ltk and alx4a genes was the highest in white koi. In order to further confirm the role of the pnp4a genes in iridophores development, the recombinant plasmid of overexpression of pnp4a gene was constructed, and was microinjected into the fertilized eggs of AB zebrafish. In order to further confirm the role of pnp4a gene in fish body colour formation, especially in iridophores, we constructed a pnp4a overexpression recombinant plasmid and microinjected it into the fertilized eggs of zebrafish (AB).

Key words: koi; iridophores; pnp4a; body color development; gene expression

（Acta Laser Biology Sinica, 2024, 33(1): 031-039）

Abstract: To address the monitoring problem in high-intensity focused ultrasound (HIFU) therapy, a new method is proposed for identification of tissue damage without the need for additional monitoring sources. The method involves studying the multiscale fuzzy entropy (MFE) of the fundamental and second harmonic of the HIFU echo. The HIFU echo signal is denoised using spectral subtraction, and then the fundamental and second harmonic components of the signal are extracted using the kullback-leibler divergence-optimized variational mode decomposition (KLD-VMD) method. Finally, the MFE combining the fundamental and second harmonic is used to identify tissue damage. The validity of the method is verified using the equal error rate (EER), where a lower EER indicates better recognition. The study also compares the KLD-VMD method with other decomposition methods such as VMD, EMD, and ITD, in combination with MFE for tissue damage identification. The experimental results demonstrate that the tissue damage identification based on KLD-VMD and MFE achieves an EER of 5.1%, which is better compared to the other methods. Furthermore, the results also show that combining the fundamental and second harmonics improves the identification performance compared to using either echo alone. This study provides a new monitoring method for HIFU therapy with potential practical applications.

Key words: HIFU echo; optimized variational mode decomposition; multiscale fuzzy entropy; identification of tissue damage; tumor treatment methods

（Acta Laser Biology Sinica, 2024, 33(1): 040-047）

Abstract: This article analyzes the research progress of pulsed light emitting diode (LED) light sources and aims to produce different wavelength pulse LED light source light panels, and to measure the variation of photosynthetic photon flux density (PPFD) at 25 cm below the lamp panel with the change of wavelength, frequency, and duty cycle of the light source. Under the condition of fixed light source duty cycle, the variation of photosynthetic rate with frequency was studied, and it was found that under different wavelengths, the plant photosynthetic rate had its respective optimized frequency; under the condition of fixed light source frequency, the variation of photosynthetic rate with duty cycle was studied, and it was found that under different duty cycles, the plant photosynthetic rate had its respective optimized duty cycle. Because its PPFD cannot be kept constant with the change of duty cycle and frequency under the condition of fixed frequency or duty cycle, the concept of photocarbon capability is proposed with photocarbon capability=photosynthetic rate⋅PPFD-1=Pn⋅PPFD-1, its biological significance is how many carbon dioxide molecules can be stimulated by a photon energy to photosynthesis. Under the condition of fixed light source duty cycle, the variation of photocarbon capacity with frequency change was studied. Each type of light source has a corresponding optimized frequency, corresponding to the maximum photosynthetic rate under this type of light source; each type of light source has a corresponding optimized frequency, corresponding to obtaining the maximum PPFD under this type of light source; each type of light source has a corresponding optimized frequency, which corresponds to the maximum photocarbon capacity under this type of light source. This article proposes a method to measure the corresponding relationship between plant lighting parameters and carbon reduction by proposing light carbon capacity. It is hoped that in the future, optical design can achieve the most economical carbon reduction by optimizing this parameter to obtain the optimal lighting conditions.

Key  words: full spectrum; photocarbon capacity; photosynthetic rate; PPFD; pulse light

CLC number: Q945.11                        Document code: ADOI:10.3969/j.issn.1007-7146.2024.01.006

Abstract: Epidermal growth factor (EGF) is a cytoprotective peptide that plays a crucial role in gut growth and health. The study mainly explored the effects of EGF on the intestinal antioxidant capacity, inflammatory response, immune status in weaning piglets. Forty-two 21-day-old weaned piglets were randomly assigned to three treatments consisting of a same basic diet containing 0 (control), 200, or 400 µg/kg EGF, respectively. There were 14 replicates per treatment, and 7 piglets per treatment were sampled on days 7 and 14 of the experiment. Dietary supplementation of 200 µg/kg EGF increased the activity of superoxide dismutase (SOD) during the entire experimental period. This supplementation decreased malondialdehyde (MDA) content whereas it increased serum immunoglobulin A (IgA) content on day 7 post-weaning. Animals receiving the diet supplemented with 400 µg/kg EGF decreased concentration of tumor necrosis factor-α (TNF-α) and tended to increase the level of secretory immunoglobulin A (SIgA) in the overall experimental period. In addition, the phosphorylation level of nuclear factor-κB (NF-κB) p65 was higher for piglets fed EGF diet. In summary, EGF can enhance intestinal antioxidant capacity, decrease inflammatory response, and increase immune status in weaned piglets, suggesting that EGF has a positive role in piglet gut health.

Key words: epidermal growth factor (EGF); antioxidant capacity; immunity; inflammation; weaning piglets

CLC number: S828.9                     Document code: ADOI:10.3969/j.issn.1007-7146.2024.01.007

Abstract: Resistance to radiotherapy is the reason for treatment failure in most patients with colorectal cancer. In this study, bioinformatics methods were used to screen differential genes (DEGs) in cancer tissues after radiotherapy, and to find therapeutic targets related to radiosensitivity. After screening the cells by cell cycle mediator ribonucleotide reductase regulatory subunit M2 (RRM2) expression, the cells were transfected with lipofectamine 2000 and irradiated with 3 Gy. Real-time fluorescence quantitative PCR and Western blot were used to detect the expression of RRM2 in colorectal cancer. Cell viability was measured by MTT assay. Flow cytometry was used to determine cell cycle and apoptosis. A total of 4 269 DEGs were identified, and RRM2 was found to be the most significant difference. Compared with intestinal epithelial FHC cells, RRM2 expression level significantly increased in tumor cells (P<0.05). Compared with NC group, RRM2 overexpression promoted cell viability. Compared with the 3 Gy group, RRM2 overexpression could delay the killing effect of radiotherapy on the cells. Compared with NC group, overexpression of RRM2 reduced the apoptosis rate, while inhibition of RRM2 increased the apoptosis rate. The combination of si-RRM2 and irradiation showed better results compared to that with si-RRM2 or irradiation alone. Overexpression of RRM2 caused cell aggregation in S phase, while knockdown of RRM2 caused cell aggregation in G1 phase. In addition, irradiation caused a significant G1 phase arrest, while RRM2 knockdown together with irradiation caused a more significant G1 phase arrest. This suggests that RRM2 mediates cell cycle of CRC cells and affects the radiosensitivity of CRC through cell cycle. This study provides important data support for the development of combined therapy for colorectal cancer.

Key words: RRM2; colorectal cancer; cell cycle; radiosensitivity; therapeutic target

（Acta Laser Biology Sinica, 2024, 33(1): 065-072）

Abstract: The composition of microbial communities on leaf surface is closely related to plant foliar diseases. However, the response in fungal community on plant leaves to the severity of pant diseases are still unknown. In this study, we used high-throughput ITS amplicon sequencing technology to investigate the differences in the composition and diversity of fungal community on plant leaves with different disease severities of powdery mildew disease in Solanaceae crops. We analyzed the changes in the topological properties of molecular ecological networks of fungal community and explored the ecological processes of community phylogenetic assembly. Diversity analysis showed that as the severity of powdery mildew disease increased, the richness and diversity of fungal communities gradually decreased. Network analysis revealed that compared to plants with moderate and severe infection, plants with mild disease symptoms had more nodes and connections in the ecological network, with higher network density, clustering coefficient, and average connectivity. Among the plants with different disease severities, the ecological processes of phylogenetic assembly in fungal communities were dominated by stochastic processes, whereas the fungal communities tended to have phylogenetic dispersion with increasing severity of powdery mildew. In conclusion, invasive pathogens alter the existing community structure, disrupt the interactions between fungal communities, and influence the ecological processes of community phylogenetic assembly. These findings provide a deep insight into the association between powdery mildew disease and the fungal community on plant leaves.

Key words: powdery mildew; phyllosphere microorganisms; fungal community; ecological network; phylogenetic structure

（Acta Laser Biology Sinica, 2024, 33(1): 073-079）

Abstract: To investigate the effects and mechanism of anlotinib intervention on glycolysis, proliferation, colony formation and migration of human lung cancer NCI-H226 cells, to provide reference for in vitro test of lung cancer. Human lung cancer NCI-H226 cells were divided into control group which is without intervention, experimental group involving 10, 20, 40 μmol/L anlotinib, and positive control group involving 20 μg/mL cisplatin. The cell counting kit-8 (CCK-8), 5-acetylene-2′ deoxyuracil riboside (EdU) staining, plate clone formation, lactic acid detection kit, glucose detection kit, Transwell assay, RT-qPCR and Western blotting (WB) assays were used to detect proliferation viability, proliferation, colony-formation ability, lactic acid content, glucose consumption level, cell migration number and expression level of related factor levels. The proliferation activity, proliferation rate, clone formation rate, lactate content, glucose consumption level, N-cadherin, vimentin and fibronectin (FN) of NCI-H226 cells in control group, experimental group and positive drug group. There were significant differences in mRNA and protein expression levels between groups (P<0.05). The cell proliferation activity of 20 and 40 μmol/L anlotinib and positive drug groups was higher than that of control group (P<0.05). The cell proliferation rate, clone formation rate, lactate content, glucose consumption level and mRNA and protein expression levels of N-cadherin, vimentin and FN in the experimental group and the positive drug group were higher than those in the control group (P<0.05). Anlotinib can significantly inhibit glycolysis, proliferation, colony formation and migration of human lung cancer NCI-H226 cells.

Key words: anlotinib; lung cancer; glycolysis; proliferation of cancer cells; colony formation

（Acta Laser Biology Sinica, 2024, 33(1): 080-089）

Abstract: To investigate the effects of cryptotanshinone on the growth and biofilm formation of Pseudomonas aeruginosa and its mechanism, the minimum inhibitory concentration (MIC) of cryptotanshinone on P. aeruginosa was determined by microdilution, and the effect of cryptotanshinone on  P. aeruginosa biofilm formation was observed by crystal violet staining, inverted microscope and laser scanning confocal microscope, and the effect of cryptotanshinone on P. aeruginosa biofilm formation was measured by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The effect of cryptotanshinone on the expression of genes related to P. aeruginosa biofilm formation was detected by RT-qPCR. The MIC of cryptotanshinone on P. aeruginosa was 800.0 μg/mL; after crystal violet staining, the best inhibition of biofilm was observed at the mass concentration of cryptotanshinone of 800.0 μg/mL in a dose-dependent manner (P<0.01). The formation and distribution of biofilm by cryptotanshinone were observed by confocal laser microscopy, and the inhibition effect was significantly enhanced at 200.0 μg/mL. In the range of 200.0～800.0 μg/mL mass concentration, cryptotanshinone at 800.0 μg/mL mass concentration inhibited the expression of LasI, LasR, RhlI and RhlR genes (P<0.01). The mechanism of cryptotanshinone inhibition of  P. aeruginosa biofilm formation may be through the down-regulation of LasI and other genes expression. The present study suggests that cryptotanshinone can be used as a group-sensing inhibitor to intervene in the drug resistance of P. aeruginosa, which can provide a reference for the treatment of multi-drug-resistant P. aeruginosa (MDR-PA) in the clinic.

Key words: Pseudomonas aeruginosa; biofilm; cryptotanshinone; quorum sensing; drug resistance

（Acta Laser Biology Sinica, 2024, 33(1): 090-096）