T helper cells (Th cells) play an important role in periodontitis. During the progression of periodontitis, the levels of pro-inflammatory cytokines such as INF-γ and IL-17, which are produced by Th1 and Th17 cells, are elevated, while the levels of anti-inflammatory cytokines such as IL-4 and TGF-β, which are secreted by Th2 cells and regulatory T cells (Tregs), are diminished. Interventions using mesenchymal stem cells (MSCs) or their exosomes can alter the dynamics of helper T cell populations and their associated cytokine profiles, thereby mitigating the bone loss associated with periodontitis or even promoting bone regeneration. Mesenchymal stem cell-derived exosomes (MSC-exos) have been shown to directly modulate Th cell activity through the proteins and microRNAs they transport. Recent studies indicate that MSC-exos carry immune-suppressive protein molecules: PD-L1 and IDO contribute to regulating the balance between Th17 and Tregs; TGF-β inhibits the proliferation of T lymphocytes while facilitating differentiation into Tregs by sustaining forkhead box protein O3 (FOXP3) and Smad expression; and CD73 catalyzes the conversion of monophosphate adenosine into adenosine, which interacts with A2A receptors on Th1 cells to induce apoptosis in Th1 cells. In addition, microRNAs exhibit immunoregulatory functions: periodontal ligament stem cell-derived exosomes contain miRNA-155-5p, which targets sirtuin-1 to suppress Th17 cell differentiation. Furthermore, evidence in rat models of periodontitis suggests that these exosomes may also carry miR-205-5p targeting XBP1 to restore the balance between Th17 and Tregs. Dental pulp stem cell-derived exosomes reestablish this balance via the miR-1246/Nfat5 axis. Bone marrow mesenchymal stem cell-derived exosomes harbor miR-1246, which targets ACE2 to promote differentiation towards Tregs. Moreover, MSC-exos can indirectly enhance the differentiation of Tregs through interactions with other immune entities, such as antigen-presenting cells or macrophages. This article reviews the changes and roles of helper T cells in periodontitis, as well as the regulatory role of exosomes on helper T cells, hoping to provide new ideas for immunotherapy in the treatment of periodontitis.

Rice is the world's largest food crop, and its yield and quality are directly related to food security and human health. Grain size, as one of the important factors determining the rice yield, has been widely concerned by breeders and researchers for a long time. To decipher the regulatory mechanism of rice grain size, we obtained a multi-tiller, dwarf, and small-grain mutant htd1 by ethyl methanesulfonate (EMS) mutation from the Japonica rice cultivar 'Zhonghua 11' ('ZH11'). Genetic analysis indicated that the phenotype of htd1 was controlled by a single recessive gene. Using the mutation site map (Mutmap) method, we identified the candidate gene OsHTD1, which encoded a carotenoid cleavage dioxygenase involved in the biosynthesis of strigolactone (SL). The SL content in htd1 was significantly lower than that in 'ZH11'. Cytological analysis showed that the grain size of the mutant decreased due to the reductions in the length and width of glume cells. The function of htd1 was further verified by the CRISPR/cas9 gene editing technology. The plants with the gene knockout exhibited similar grain size to the mutant. In addition, gene expression analysis showed that the expression levels of multiple grain size-related genes in the mutant changed significantly, suggesting that HTD1 may interact with other genes regulating grain size. This study provides a new theoretical basis for research on the regulatory mechanism of rice grain size and potential genetic resources for breeding the rice cultivars with high yields.
Oryza/growth & development* ; Mutation ; Edible Grain/growth & development* ; Alleles ; Plant Proteins/genetics* ; Dioxygenases/genetics* ; Lactones/metabolism* ; Gene Expression Regulation, Plant ; Genes, Plant ; Gene Editing ; CRISPR-Cas Systems ; Phenotype

Objective:To explore the differentially expressed tRNA-derived RNA fragment(tRF)and tRNA halves(tiRNA)in plasma of collagen-induced arthritis(CIA)rats,analyze the biological functions and related pathways of the tRF and tiRNAs target genes in order to identify new targets for diagnosis and therapy of rheumatoid arthritis(RA).Methods:Rat model of RA was estab-lished by injecting typeⅡ collagen.Arthritis index(AI)score and HE staining were conducted to evaluate the successfully establishment model.Illumina platform was used to obtain the tRF and tiRNA expression profiles.RT-qPCR was performed to validate expressions of tRF and tiRNA.Combining miRanda and TargetScan databases,the target genes of differentially expressed tRF and tiRNA were ob-tained.GO and KEGG enrichment analysis were used to annotate the functions of target genes.Results:A total of 25 tRFs and tiRNAs were significantly differentially expressed in plasma in rats after modeling,of which 23 were up-regulated and 2 were down-regulated.Besides,six specifically expressed tRFs and tiRNAs induced by CIA rats were screened,including Other-36:73-tRNA-Arg-CCT-4,Other-57:70-tRNA-Glu-CTC-1-M3,tRF-1:32-Gly-CCC-1-M2,tRF-1:31-Gly-CCC-1-M2,tRF-1:32-Pro-AGG-1-M4 and tRF-1:32-Glu-TTC-2-M2.GO analysis of target genes mainly involved organelle-associated items.What's more,KEGG analysis enriched multi-ple classical signal pathways associated with RA.Conclusion:Target genes of differentially expressed tRFs and tiRNAs in CIA rats may be involved in regulating important pathophysiological processes of RA and drug therapy targets.

Objective:To explore the differentially expressed tRNA-derived RNA fragment(tRF)and tRNA halves(tiRNA)in plasma of collagen-induced arthritis(CIA)rats,analyze the biological functions and related pathways of the tRF and tiRNAs target genes in order to identify new targets for diagnosis and therapy of rheumatoid arthritis(RA).Methods:Rat model of RA was estab-lished by injecting typeⅡ collagen.Arthritis index(AI)score and HE staining were conducted to evaluate the successfully establishment model.Illumina platform was used to obtain the tRF and tiRNA expression profiles.RT-qPCR was performed to validate expressions of tRF and tiRNA.Combining miRanda and TargetScan databases,the target genes of differentially expressed tRF and tiRNA were ob-tained.GO and KEGG enrichment analysis were used to annotate the functions of target genes.Results:A total of 25 tRFs and tiRNAs were significantly differentially expressed in plasma in rats after modeling,of which 23 were up-regulated and 2 were down-regulated.Besides,six specifically expressed tRFs and tiRNAs induced by CIA rats were screened,including Other-36:73-tRNA-Arg-CCT-4,Other-57:70-tRNA-Glu-CTC-1-M3,tRF-1:32-Gly-CCC-1-M2,tRF-1:31-Gly-CCC-1-M2,tRF-1:32-Pro-AGG-1-M4 and tRF-1:32-Glu-TTC-2-M2.GO analysis of target genes mainly involved organelle-associated items.What's more,KEGG analysis enriched multi-ple classical signal pathways associated with RA.Conclusion:Target genes of differentially expressed tRFs and tiRNAs in CIA rats may be involved in regulating important pathophysiological processes of RA and drug therapy targets.

Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.
Mice ; Animals ; Epilepsy, Temporal Lobe/pathology* ; Parvalbumins/metabolism* ; Parkinson Disease/pathology* ; Neurons/metabolism* ; Interneurons/physiology* ; Disease Models, Animal ; Brain/pathology*

Surgical resection in patients with advanced primary carcinoma of liver has high risks of early recurrence and incidence of portal vein tumor thrombus, caused by insufficient resi-dual liver volume after two-steps hepatotomy. At present, the treatment for patients with advanced primary carcinoma of liver is limited, thus can't satisfy the requirement of patient for treatment. The authors introduce the clinical experience of a patient with hepatocellular carcinoma and insufficient residual liver volume who underwent preventive immunotherapy plus target therapy after associa-ting liver partition and portal vein ligation for staged hepatectomy, in order to provide reference for relevant treatment.

Objective:To explore the short-term outcomes of reconstruction of tumorous critical bone defects at femoral shaft with a 3D printed ultra-short stem with a porous structure.Methods:From September 2016 to June 2018, 8 patients underwent reconstruction of critical bone defects with a 3D printed ultra-short stem with a porous structure after resection of femoral shaft malignant tumor at Department of Orthopaedics, West China Hospital. There were 4 males and 4 females, with an average age of 36.9 years (from 11 to 61 years). Their preoperative Enneking staging was stage Ⅱb in all. There were 3 osteosarcomas, 2 Ewing sarcomas, 2 chondrosarcomas and one periosteal osteosarcoma. Preoperative CT/MRI image fusion technology was used to define the surgical boundary, design the guide plate and prosthesis, and perform surgical simulation. Tomosynthesis-shimadzu Metal Artefact Reduction technology was used to evaluate osseointegration. Complications and bone oncology prognosis of the patients were documented. The lower limb function of the patients was evaluated using Musculoskeletal Tumor Society (MSTS) 1993 scoring and knee range of motion.Results:The overall follow-up time ranged from 36 to 50 months, averaging 42.8 months. During operation one patient sustained a periprosthesis fracture, the union of which was followed up after wire assisted fixation. There was no local tumor recurrence, lung metastasis or death. The last follow-up revealed good osseointegration and basically isometric lower extremities in all cases. There was no such a complication as aseptic loosening of the prosthesis, deep infection or prosthesis fracture during the follow-up period. At the last follow-up in the 8 patients, the flexion range of the knee joint was 116.2°±9.1°, significantly improved compared with that before operation (98.8°±10.9°), and the MSTS score was (26.2±2.1) points, also significantly improved compared with that before operation [(21.6±1.8) points] ( P<0.05). Conclusions:Reconstruction with a 3D printed ultra-short stem with a porous structure is an accurate operation for femoral shaft tumorous bone defects. With careful preoperative design, intraoperative manipulation and strict postoperative follow-up management, this operation can lead to fine early curative outcomes for long shaft critical bone defects.

Arterial stiffness plays a major role in the pathogenesis of numerous age-related diseases.Pulse wave velocity, distensibility, wave reflection, and pulse pressure are used to assess arterial stiffness, but the features and clinical significance of each parameter are different.Combined application of these parameters can comprehensively evaluate arterial stiffness.This review summarizes the methods and research progress of noninvasive assessment of arterial stiffness.

Objective:To investigate the difference of physical growth and neurodevelopmen between small for gestational age (SGA) preterm infants and appropriate for gestational age (AGA) preterm infants, and to promote follow-up management and early intervention in SGA preterm infants after discharge.Methods:Preterm infants, who were born at Guangzhou Women and Children′s Medical Center and received regular follow-up management after discharge in high-risk infants outpatient, were enrolled in this study from January 2015 to December 2018.According to gestational age and birth weight, the participants were divided into SGA group and AGA group.Height, weight, head circumference and Gesell outcomes of infants were observed at 6 months and 12 months of corrected age.Results:A total of 144 preterm infants were included in the study, including 63 cases in SGA group and 81 cases in AGA group. Height, weight and head circumference of the SGA group at 6 months and 12 months of corrected age were all lower than the AGA group ( P<0.05). In addition, adaptability, great movement, language, personal social interaction and development quotient in the SGA group were all lower than those in the AGA group at 6 months of corrected age ( P<0.05), while fine movement was not statistically significant ( P>0.05). At 12 months of corrected age, there were no statistically significant differences in adaptability, macro motor, fine motor, language, social interaction and development quotient between the two groups ( P>0.05). Conclusion:The physical growth of SGA preterm infants falls for behind that of AGA preterm infants.It is still unable for SGA preterm infants to achieve catch-up growth at 12 months of corrected age, their catch-up period may take longer, but the neurodevelopment can reach the same level of preterm AGA.The clinician should pay more attention to the follow-up management and early intervention after discharge.