PubMed Health⌕ Search

Biomedical subjects

Xinyu Yang

Publications and source records attributed to Xinyu Yang.

18 recordsLinked to original sources

Integrating structure and experimental data annotations with computational modeling framework for predicting micro-nanoplastics toxicities.

The wide use of plastic materials leads to increased emissions of micro-nanoplastics (MNPs) into the environment, raising significant concerns about their impact on human health. Traditional experimental approaches for assessing MNPs toxicity are costly, time-consuming, and there are no experimental protocols that are universally acceptable. Computational modeling using machine learning (ML) approaches provides an efficient alternative to MNP toxicity assessment. However, most modeling studies of MNPs are limited due to the lack of high-quality data and there are few previous modeling studies considering complex structures of MNPs for model training. To address this challenge, we constructed three MNP datasets with popular toxicity endpoints from various resources and used nanostructure annotation techniques to create virtual MNPs (vMNPs) for all MNP structures. The MNP structures were digitalized from annotated vMNPs, and geometrical descriptors were calculated using the Delaunay Tessellation approach. Moreover, important experimental information, such as concentrations and cell lines, were transformed into extra training variables. Partial least squares regression (PLSR) models were built using both experimental and geometrical descriptors and validated through a leave-one-out cross validation procedure. The resulting models showed reasonable performance in predicting toxicity potentials of MNPs for the three endpoints in the present datasets. Moreover, an additional library of vMNPs with their predicted properties and bioactivities was constructed, directing further research of new MNPs. This study provides three novel ML models for MNPs by integrating geometrical and experimental descriptors, which have the potential to assess new MNPs for their toxicity. The modeling strategy developed in this study can be easily expanded to model other MNP toxicity endpoints and create promising new models for MNP toxicity assessments.

Data annotation↗

Effects of digital health-based exercise interventions on older adults with sarcopenia: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Sarcopenia, the progressive loss of muscle mass and function, impairs independence in older adults. Digital health exercise interventions are scalable solutions for older adults with sarcopenia. This systematic review and meta-analysis aimed to synthesize the evidence on their efficacy in populations with clinically diagnosed sarcopenia and identify influential intervention characteristics associated with treatment outcomes. METHODS: We systematically searched PubMed, EMBASE, Web of Science, Cochrane Library, CINAHL, CNKI, and Wanfang on May 20, 2026, with no date restrictions. We included randomized controlled trials involving adults aged &#x2265;60 with sarcopenia receiving digital exercise interventions. Two reviewers independently screened studies, extracted data, and assessed risk of bias; analyses were performed using R and Review Manager. RESULTS: Fourteen trials (n&#xa0;=&#xa0;927) were included. Digital interventions showed potential improvements in muscle mass (MD&#xa0;=&#xa0;0.25, 95%CI:0.03-0.46, 95% PI:-0.36 to 0.85), muscle strength (MD&#xa0;=&#xa0;2.14, 95% CI:1.18-3.11, P&#xa0;<&#xa0;0.001), balance ability (SMD&#xa0;=&#xa0;0.31, 95% CI:0.12-0.51, P&#xa0;=&#xa0;0.001), walking performance (SMD&#xa0;=&#xa0;0.55, 95% CI:0.21-0.89, 95% PI:-0.70 to 1.79), and physical function (SMD&#xa0;=&#xa0;0.89, 95% CI:0.08-1.71, 95% PI:-2.33 to 4.12), but not quality of life (SMD&#xa0;=&#xa0;0.08, 95% CI:-0.19 to 0.35, P&#xa0;=&#xa0;0.53). Exploratory subgroup analyses suggested that factors such as supervision, program duration, and measurement tools may influence outcomes; however, formal tests for subgroup differences were generally non-significant, and consistent patterns across all metrics were not observed. CONCLUSION: Digital exercise interventions show potential for managing sarcopenia in older adults, though the very low to moderate certainty of evidence indicates that true effects may differ substantially from observed estimates. This review explores potential roles of intervention design, supervision, and multimodal delivery. Future research should adopt rigorous designs and longer follow-up to validate results and enhance clinical application. TRIAL REGISTRATION: PROSPERO CRD420251135174.

Humans↗

PSMB8: an immune-related prognostic marker for low-grade gliomas.

BACKGROUND: Glioma is the most common primary intracranial tumor in adults. As a subunit of immune proteasome, proteasome subunit beta type-8 (PSMB8) may regulate the progression of glioma via participating in degradation and presentation of tumor antigenic peptides, but its prognostic and clinical applicant usage is under investigation. Therefore, this study aimed to comprehensively evaluate the prognostic significance of PSMB8 in low-grade glioma (LGG) and to elucidate its association with the tumor immune microenvironment and potential as a predictor for immunotherapy response. METHODS: Transcriptome data were downloaded from The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), Gene Expression Omnibus (GEO) repositories. The correlations between PSMB8 expression and the clinicopathological features of LGG were investigated in our study, and the prognostic role of PSMB8 in LGGs was assessed fully and comprehensively. Furthermore, we evaluated the correlation between PSMB8 expression and LGG immune environment via the experiments and bioinformatic analysis. RESULTS: Our results indicated that, PSMB8 were highly expressed in most tumor tissues, including LGG. Lower expression of PSMB8 was significantly correlated with lower World Health Organization (WHO) grade and isocitrate dehydrogenase (IDH) mutation status. Moreover, PSMB8 showed a promising prognostic ability for LGG patients via nomogram model and receiver operating characteristic (ROC) curves. Association analysis showed that PSMB8 expression was associated with immune cell infiltration in a variety of tumors, including LGG. Our experiments validated the positive correlation between PSMB8 expression and M2-macrophage infiltration level in clinical LGG tissues and invasive ability of LGG cell. CONCLUSIONS: PSMB8 could be used as one of the prognostic indicators of LGG and it could regulate the LGG cell migratory and invasive ability. Besides, PSMB8 is expected to be a promising biomarker of cancer immunotherapy.

Low-grade glioma (LGG)↗

Ossicle occurrence characteristics and related molecular mechanisms in the sea cucumber Apostichopus japonicus.

To investigate the morphogenetic pattern and molecular mechanism of ossicle formation in the sea cucumber Apostichopus japonicus, this study systematically examined the morphological development and temporal sequence of spicules using the NaClO maceration method, in-situ squash preparation and microscopic observation. Comparative transcriptome sequencing was performed between doliolaria and pentactula larvae to screen differentially expressed genes (DEGs) related to ossicles formation, followed by pathway enrichment analysis. The function of the candidate key gene papilin-like was verified using siRNA-mediated gene silencing. The results were as follows: 1) Ossicles of A. japonicus first appeared at the late auricularia stage, initiating as X-shaped ossicles at the base of the oral tentacles. The number of X-shaped ossicles increased dramatically during the doliolaria stage. X-shaped ossicles were gradually replaced by table-shaped and rosette-shaped ossicles at the pentactula stage, suggesting that X-shaped ossicles may differentiate into these two ossicle types. The morphology of table-shaped ossicles showed a "simple-complex-simple" pattern with development. 2) Key genes related to ossicles formation, including CA1, COL1A2, and papilin-like, were identified by transcriptome analysis. After papilin-like knockdown, abnormal morphologies were observed in table-shaped ossicles of 1-year-old A. japonicus, such as spine-like protrusions on the outer margin of the disc and loss of table legs, confirming its crucial roles in maintaining ossicle morphology. This study clarified the morphological development pattern of ossicles in A. japonicus and identified a key regulatory gene (papilin-like) involved in ossicle morphogenesis, providing preliminary insights into the underlying molecular regulatory mechanism. These findings enrich our understanding on ossicles formation in echinoderms, and provide important morphological and molecular biological information for further studies on the developmental mechanism of ossicles in A. japonicus.

Animals↗

Genome-wide identification of the HSP70 superfamily in tropical sea cucumber Stichopus monotuberculatus and their expression analysis under low-salinity stress.

Heat shock proteins (HSPs) are a group of evolutionarily conserved molecular chaperones that serve as indispensable core regulators in preserving cellular homeostasis and orchestrating organismal stress responses. The tropical sea cucumber Stichopus monotuberculatus, a high-value aquaculture species, is sensitive to fluctuations in environmental salinity-a challenge that has emerged as a critical bottleneck limiting its large-scale commercial cultivation. However, no systematic investigation has been conducted to characterize the HSP70 superfamily in S. monotuberculatus and elucidate its functional roles in salinity adaptation. In the present study, we performed a comprehensive genome-wide scan and identified 19 HSP70 superfamily genes in the S. monotuberculatus genome, with the HSP70IV subfamily showing remarkable gene expansion, containing 8 distinct copies. Phylogenetic analysis, conserved motif identification, and gene structure characterization demonstrated high evolutionary conservation within each HSP subfamily. These genes were unevenly distributed across the chromosomes of S. monotuberculatus, and prediction of cis-acting elements revealed that their upstream regulatory regions were enriched with numerous functional elements associated with stress response and immune regulation. Salinity stress experiments revealed that under severe low-salinity conditions (18&#x2030;), the expression levels of SmHSPA14L and multiple HSP70IV subfamily members were significantly elevated, while SmHYOU1D was significantly downregulated; in contrast, only subtle changes were detected in the expression of most HSP70 genes under moderate low-salinity stress (24&#x2030;). These findings strongly suggest that HSP70 genes, particularly the expanded HSP70IV subfamily, may act as key modulators in the low-salinity stress response. This work provides valuable insight into the molecular mechanisms underlying salinity adaptation in tropical sea cucumbers.

Animals↗

Molecular adaptation of caspase genes to salinity stress in the tropical sea cucumber Stichopus monotuberculatus: A comparative analysis across echinoderms.

Apoptosis is an essential physiological process that plays a critical role in development and tissue homeostasis. Caspases, as central regulators of apoptosis, are crucial in controlling inflammation and cell death. In this study, we investigated the caspase gene family in Stichopus monotuberculatus to explore their potential roles in salinity stress adaptation. Five caspase genes were identified from the genome of S. monotuberculatus, including Smcaspase3, Smcaspase6, Smcaspase8a, Smcaspase8b, and Smcaspase8c. Phylogenetic analysis revealed that these Smcaspase genes clustered into distinct caspase subfamilies and showed high conservation with homologs from other echinoderms and representative vertebrates. Conserved motif and gene structure analyses showed relatively similar structural patterns within each clade, whereas divergence was observed among different subfamilies. Promoter analysis identified numerous cis-acting elements related to gene regulation, immune response, and growth and development. Expression profiling under salinity stress showed that Smcaspase8a was significantly upregulated, particularly under prolonged stress, whereas the other genes exhibited limited transcriptional responses. Our findings highlight caspase function in salinity stress and provide the foundation of molecular salinity adaptation mechanisms in S. monotuberculatus.

Animals↗

An image-based protein-ligand binding representation learning framework via multi-level flexible dynamics trajectory pre-training.

MOTIVATION: Accurate prediction of protein-ligand binding (PLB) relationships plays a crucial role in drug discovery, which helps identify drugs that modulate the activity of specific targets. Traditional biological assays for measuring PLB relationships are time consuming and costly. In addition, models for predicting PLB relationships have been developed and widely used in drug discovery tasks. However, learning more accurate PLB representations is essential to meet the stringent standards required for drug discovery. RESULTS: We propose an image-based PLB representation learning framework, called ImagePLB, which equips ligand representation learner (LRL) and protein representation learner (PRL) to accept 3D multi-view ligand images and protein graphs as input, respectively, and learns rich interaction information between ligand and protein through a binding representation learner (BRL). Considering the scarcity of protein-ligand pairs, we further propose a multi-level next trajectory prediction (MLNTP) task to pre-train ImagePLB on the 4D flexible dynamics trajectory of 16&#x2009;972 complexes, including ligand level, protein level, and complex level, to learn information related to trajectories. Besides, by introducing trajectory regularization (TR), we effectively alleviate the problem of high (even almost identical) feature similarity caused by adjacent trajectories. Compared with the current state-of-the-art methods, ImagePLB has achieved competitive improvements on PLB-related prediction tasks, including protein-ligand affinity and efficacy prediction tasks. This study opens the door to the image-based PLB learning paradigm. AVAILABILITY AND IMPLEMENTATION: All data and implementation details of code can be obtained from https://github.com/HongxinXiang/ImagePLB.

Ligands↗

A hypoxia-responsive tRNA-derived small RNA confers renal protection through RNA autophagy.

Transfer RNA-derived small RNAs (tsRNAs or tDRs) perform a range of cellular functions. Here, we showed that tRNA-Asp-GTC-3'tDR, a hypoxia-induced tDR derived from the 3' end of tRNA-Asp-GTC, activated autophagic flux in kidney cells and its silencing blocked autophagic flux. Functional gain-/loss-of-function studies in murine kidney disease models demonstrated a substantial renoprotective function of tRNA-Asp-GTC-3'tDR. Mechanistically, tRNA-Asp-GTC-3'tDR assembled stable G-quadruplex structures and sequestered pseudouridine synthase 7 (PUS7), preventing catalytic pseudouridylation of histone mRNAs. The resulting pseudouridylation deficiency directed histone mRNAs to the autophagosome-lysosome pathway, triggering RNA autophagy. This tDR-induced RNA autophagy pathway was activated during murine and human kidney diseases, suggesting clinical relevance. Thus, tRNA-Asp-GTC-3'tDR plays a role in regulating RNA autophagy, which helps to maintain homeostasis in kidney cells and protects against kidney injury.

Animals↗

Stereo-cell: Spatial enhanced-resolution single-cell sequencing with high-density DNA nanoball-patterned arrays.

Single-cell sequencing technologies have advanced our understanding of cellular heterogeneity and biological complexity. However, existing methods face limitations in throughput, capture uniformity, cell size flexibility, and technical extensibility. We present Stereo-cell, a spatial enhanced-resolution single-cell sequencing platform based on high-density DNA nanoball (DNB)-patterned arrays, which enables scalable and unbiased cell capture at a wide input range and supports high-fidelity transcriptome profiling. Stereo-cell further allows integration with imaging-based modalities and multiomics strategies, including immunofluorescence and epitope profiling. This platform is also compatible with profiling extracellular vesicles, microstructures, and large cells, whereas its spatial resolution facilitates in situ analysis of cell-cell interactions, cellular microenvironments, and subcellular transcript localization. Together, Stereo-cell provides a flexible framework for expanding single-cell research applications.

Animals↗

Aberrant methylation of the 8p22 tumor suppressor gene DLC1 in renal cell carcinoma.

Epigenetic mechanisms involving DNA methylation and chromatin remodeling are important in silencing tumor suppressor genes (TSG) in various malignancies, including renal cell carcinoma (RCC). DLC1 (deleted in liver cancer 1)/ARHGAP7 is a recently identified 8p22 candidate TSG. Frequent methylation of the DLC1 promoter with resultant gene silencing has been reported in several tumors, but not in RCC yet. We examined DLC1 promoter methylation in 34 primary RCCs and the corresponding non-malignant tissues, and the correlation of DLC1 methylation with the clinicopathological characteristics of RCC patients. Although DLC1 methylation and downregulation were only detected in one of seven RCC cell lines using methylation-specific PCR (MSP) and semi-quantitative reverse-transcription PCR, we found that the DLC1 promoter was methylated in 35% (12/34) of primary RCC tumors, which was further confirmed by direct sequencing of MSP products and high-resolution bisulfite genomic sequencing. In contrast, only one of the 34 (3%) non-malignant renal tissues had weak methylation. Aberrant DLC1 methylation appeared to be a relatively early event during renal tumorigenesis since 33% of the RCC tumors with pT1 (TNM staging) showed methylation, which is similar to other late stage tumors. Thus, our results demonstrated that DLC1 methylation occurs in a subset of RCC tumors and may play a role in renal carcinogenesis.

Adult↗

Expression of transforming growth factor and basic fibroblast growth factor and core protein of proteoglycan in human vertebral cartilaginous endplate of adolescent idiopathic scoliosis.

STUDY DESIGN: To compare the expression of cytokines and core protein of proteoglycan in the scoliotic concave and convex cartilaginous endplate using immunohistochemical staining. OBJECTIVES: To define the possible role of transforming growth factor beta 1 (TGFbeta1), basic fibroblast growth factor (bFGF), and core protein of proteoglycan in the development of adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Changes in the endplate composition have been implicated as possible etiologic factors in the pathogenesis of adolescent idiopathic scoliosis. Cytokines have exclusive effects on cartilage. Thus comparing the expression of the cytokines and matrix on the convex and concave sides of scoliotic endplate tissues may help to understand the role of endplate tissues in the induction and/or progression of idiopathic scoliosis. METHODS: The convex and concave half of cartilage endplate was collected at the apex and end vertebrae from 12 patients. The expression of TGFbeta1, bFGF, and core protein on both sides was examined with the immunohistochemistry method, and results were analyzed with the image analysis system. RESULTS: TGFbeta1, bFGF, and core protein of proteoglycan were all expressed in the cytoplasm of chondrocytes in the cartilaginous endplate. The area density and quantity density of TGFbeta1 and bFGF on the concave side are expressed in an even significantly higher level than that on the convex side (P > or = 0.05). The expression of the core protein of proteoglycan on the convex side is higher than that on the concave side, the difference is not significant (P > 0.05). CONCLUSION: There was a significantly higher expression of TGFbeta1 and bFGF, although a lower expression of the core protein on the concave side, which suggests a possible etiological factor or a secondary change in the development of adolescent idiopathic scoliosis.

Adolescent↗

A new operative classification of idiopathic scoliosis: a peking union medical college method.

STUDY DESIGN: A retrospective radiographic study on the type of surgically treated idiopathic scoliosis, with a prospective study on the reliability of the type-related fusion guide. OBJECTIVES: To identify and classify surgically treated idiopathic scoliosis, and define its related fusion levels by a new classification system. SUMMARY OF BACKGROUND DATA: Some classification methods for idiopathic scoliosis have been suggested. However, poor intraobserver reproducibility and interobserver reliability were experienced in these studies, and were not appropriate for guiding surgical planning. METHODS: A total of 427 surgically treated idiopathic scoliosis cases were reviewed. Preoperative and postoperative standing anteroposterior, lateral, and preoperative supine side-bending radiograph were analyzed using the Scoliosis Research Society definition of scoliosis and curve apex. The resulting classification was tested for intraobserver reliability and interobserver reliability, and by 6 surgeons. Apical frequencies were determined for each type, and prospective surgical testing of the new type and its related fusion guide was performed. RESULTS: Three major types and 13 subtypes were identified, of which the Peking Union Medical College type I accounted for 56.62%, type II 42.16%, and type III 1.22%. The interobserver reliability testing was 85% (kappa coefficient 0.832), while intraobserver reproducibility was 91% (kappa coefficient 0.898). Each type had its corresponding fusion levels. A prospective study of 152 cases was performed according to the classification. All of these cases were followed over 18 months, and no postoperative decompensation was noted. CONCLUSION: The Peking Union Medical College classification of idiopathic scoliosis is one system to combine each type with its corresponding fusion level, and it had much higher interobserver reliability and intraobserver reproducibility than the King system. Further prospectivestudies would help to clarify and expand this system.

Adolescent↗

[Seminiferous tubule scores used for quantitative assessment of spermatogenic function of patients with azoospermia].

OBJECTIVE: To investigate the clinical reliability of quantitative evaluation by seminiferous tubule scores on spermatogenesis dysfunction, using the testis tissues of azoospermia patients for analysis of histological changes. METHODS: One hundred and twelve Chinese patients with azoospermia underwent open testicular biopsy and their testicular biopsy specimens were evaluated by 10-score (on testicular biopsy) and 5-Grade (on seminiferous tubule spermatogenesis) scale. The 112 patient, 22 to 46 years old [(29.0 +/- 4.4) years old] included 105 cases of obstructive and 7 cases non-obstructive azoospermia. Of the total number, there were 96 primary infertile cases and 16 secondary infertile cases with infertile marriage of 2-12 years [(4.0 +/- 2.8) years]. Various seminiferous tubule characteristics were categorized by 10-score as follows: [1] degenerating Sertoli cells and no germinal epithelium; [2] no germ cells and only Sertoli cells; [3] no spermatids and primary spermatocytes and only spermatogonia; [4] no spermatids and few primary spermatocytes; [5] no spermatids and numerous primary spermatocytes; [6] no mature spermatids and few round immature spermatids; [7] no mature spermatids and numerous round immature spermatids; [8] < 20 mature spermatids/tubules, germinal epithelium height < 80 microns and spermiation absent; [9] > 20 mature spermatids/tubules, germinal epithelium height < 80 microns and spermiation rarely < 80 microns; [10] > 20 mature spermatids/tubule and germinal epithelium height 80 microns and spermiation common. Seminiferous tubule spermatogenesis was catagorized by 5-Grade scale as follows: [1] tubular sclerosis; [2] sertoli cell only; [3] arrested spermatogenesis; [4] reduced spermatogenesis; [5] intact spermatogenesis. RESULTS: In terms of the 10-score scale on testicular biopsy, scores of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 corresponded with total patient numbers of 5 (4.5%), 38(33.9%), 2(1.8%), 6(5.4%), 2(1.8%), 17(15.2%), 6(5.4%), 19(17%), 10(8.9%) and 7(6.3%), respectively. According to the 5-Grade scale on the seminiferous tubule spermatogenesis, Grades 1, 2, 3, 4 and 5 corresponded with 5(4.5%), 38(33.9%), 33(29.5%), 29(25.9%) and 7 (6.3%), respectively. Tubular diameter, the thickness of the lamina propria, the height of the germinal epithelium and serum FSH correlated with the average seminiferous tubule scores (P < 0.01). CONCLUSION: The seminiferous tubule scores obtained through testicular biopsy may provide important quantitative information concerning the etiology and pathogenesis and of azoospermia may serve as a helpful guide to the fundamental, clinical and therapeutical study of element, clinic and therapy.

Adult↗

[Use of biopsy results to predict capsular perforation and seminal vesicle invasion in prostate cancer].

OBJECTIVE: To determine the ability of clinical tests to predict extraprostatic cxtension and seminal vesicle invasion. METHODS: Clinical T stage, TPSA total prostate specific antigen and pathologic features in systematic biopsy specimens were correlated with pathologic stage in 40 consecutive patients with clinically localized prostate cancer detected by systematic needle biopsies and treated with radical prostatectomy. RESULTS: Extraprostatic extension was observed in 20 patients (50%) and seminal vesicle invasion was noted in 11(28%). Preoperative variables predictors of extraprostatic extension and seminal vesicle invasion on univariate analysis were TPSA, Gleason score, the total length of cancer, the number of positive cores, the percentage of positive cores, the maximum length of cancer in any one core in the biopsy specimen and the percentage of cancer in the biopsy set P<0.05 . In multivariate analysis, TPSA, Gleason score, the total length of cancer and the percentage of positive cores in the biopsy specimens were the only significant predictors of extraprostatic extension and seminal vesicle invasion P<0.01 . A model was constructed to predict advanced stage: the TPSA >or=11 microg x L(-1) and Gleason score/5 and percentage of positive cores in the biopsy specimen >or=27% or the total length of cancer>or=7.3 mm P<0.001 . CONCLUSION: The combination of TPSA, the total length of cancer, Gleason score and percentage of positive cores in the biopsy specimens provides the best prediction of capsular perforation and seminal vesicle invasion. Models based on this combination of factors may be clinically useful to stratify patients for nonoperative treatment.

Aged↗

Role of Caspase 3 in neuronal apoptosis after acute brain injury.

OBJECTIVE: To analyze the role of Caspase 3 in neuronal apoptosis after acute brain injury. METHODS: Experiments were carried out with rat diffuse brain trauma model. The neuronal DNA injury in cortex and hippocampus was observed by TUNEL stain. The mRNA and protein expressions and enzyme activation of Caspase 3 were observed by Northern blot, in situ hybridization, immunohistochemistry stain and Western blot, respectively. Special Caspase 3 enzyme inhibitor was used to observe the therapeutic effect. RESULTS: TUNEL positive neurons appeared 2 hours after severe trauma, peaked at 1 day and lasted for 7 days. Northern blot showed that the Caspase 3 mRNA expression was increased and peaked at 1 day, about twice higher than the control. In the area of cortex and hippocampus, positive mRNA staining neurons appeared most distinct on one day. With the antibody for Caspase 3 P20 subunit, the active Caspase 3 expression peaked at 1-3 days. The electrophoresis band of PARP degradation would be seen by Western blot. Caspase 3 enzyme inhibitor could reduce apoptotic neuronal death without any effect on Caspase 3 P20 subunit expression. CONCLUSIONS: After brain trauma, Caspase 3 mRNA and protein expressions and enzyme activation are enhanced in combination with neuronal apoptosis. Special Caspase 3 enzyme inhibitor can apparently decrease the neuronal apoptosis.

Acute Disease↗

[Expression and significance of bcl-2 and bcl-xL in rat neuron after acute brain trauma].

OBJECTIVE: To observe the expression of bcl-2 and bcl-xL in rat brain neuron after acute brain trauma. METHODS: The rat model of mild and sever brain trauma were made by diffused brain injury. The expression of bcl-2 and bcl-xL in rat brain neuron was examined by immunohistochemical staining. Rat neuron apoptosis was detected by TUNEL method. RESULTS: There were few bcl-2 (cortex: 4.40 +/- 1.67, hippocampal: 3.20 +/- 1.30) and lots of bcl-xL (cortex: 45.60 +/- 4.34, hippocampal: 50.20 +/- 3.50) expression in normal controls. After impact, the expression of bcl-2 in rat brain neuron increased, most distinctly on day 1(cortex: 30.0 +/- 4.3, hippocampal: 46.6 +/- 3.2), in mild group. A negative correlation was seen between bcl-2 expression and neuronal apoptosis (-1 < r < -0.847, P< 0.01, n = 10). No change was seen in bcl-xL expression. CONCLUSIONS: bcl-2 expression increased after acute brain trauma but bcl-xL did not change much. Both bcl-2 and bcl-xL are concerned with anti-apoptosis in neuron after acute brain trauma.

Acute Disease↗

[Surgical treatment of lumbar spinal stenosis associated with unstable degenerative spondylolisthesis].

OBJECTIVES: To assess surgical treatment of lumbar spinal stenosis associated with unstable degenerative spondylolisthesis. METHODS: In 86 patients with lumbar spinal stenosis associated with unstable degenerative spondylolisthesis. (30 men and 56 women, aged from 30 to 77 years), 63 patients complained of lower back pain with both lower extremity pain, 10 patients pain in one leg, and 13 patients only lower back pain. Seventy-two of these patients complained of intermittent claudication, with a walking distance ranging from 10 to 1 000 m. Thirty-two patients had some changes in sensation, motion and reflexes of the foot. According to White' critera, all patients showed dynamic instability of the lesion. Meyerding criteria showed degree 1 in 79 patients, and degree 2 in 7. CT scan was made in 56 patients, MRI in 24 and MRM in 6 before operation. Myelography was performed in 61 patients, and CTM in 6. Stenosis and spondylolisthesis located between L(4) and L(5) in 49 patients, between L(3) and L(4) in 6, between L(5) and S(1) in 25, between L(3) and L(4) and between L(4) and L(5) in 2, and from L(3) to S(1) in 4. The patients with pathological spondylolisthesis were excluded. Lateral recess stenosis of one leg was observed in 10 patients, lateral recess of both legs in 22, and central canal stenosis in 54, of whom 12 patients were associated with protrusion of the lumbar disc. Decompression and autograft with iliac bone and various internal fixation were performed in all patients. RESULTS: The patients were followed up from 8 months to 13 years, longer than 1 year (average 5.6 years) in 81 patients. According to Amundsen et al, excellent results were obtained in 78 patients, good in 5, and fair in 3. Spondylolisthesis was completely reduced in 70 patients of degree 1 (89.9%), and in 6 patients of degree 2 (85.7%). No patient showed slippage aggravated. 74 patients gained bone graft fusion within 3 months and 10 patients within 6 months. Two patients showed pseudoarthrosis during the follow-up. Complications included internal fixation breakage in 1 patient, and delayed infection in 1. CONCLUSIONS: Complete decompression and bone graft fusion are the key to treatment. Decompression and internal fixation improve the symptoms of patients with lumbar spinal stenosis associated with spondylolisthesis. Transpedicle instrumentation can reduce spondylolisthesis and maintain the physical curve of the lumbar.

Adult↗

[Effects of chrysotile asbestos on the activities of cytochrome P4501A1 and glutathione S-transferase in A549 cell line].

OBJECTIVE: To study the effects of chrysotile on the activities of some enzymes for xenobiotics metabolism. METHODS: UICC chrysotile (UC) and China Mangya chrysotile (MC) asbestos fibers were used at different doses (0, 25, 50, 100, 200 mg/L) to study its effects on the activities of cytochrome P4501A1 and glutathione S-transferase (GST) in A549 cell line. Also, the effects of chrysotile on the activities of CYP1A1 and GST induced by benzo(a)pyrene were studied. RESULTS: The activity of EROD increased slowly with the increasing dose of UC, as A549 cells were incubated with UC for 24 h, and EROD activity increased by 40% at a dose of 200 mg/L UC. However, activity of EROD decreased by 32% with 48 h incubation at the same dose, indicating that lower dose of UC and short time could induce the activity of EROD in A549 cells, whereas higher doses and long time could inhibit its activity. MC exhibited a multiphasic effects on the activity of EROD, whether at a dose of 25 mg/L for 24 h or 48 h all gave the strongest induction, 1.86 times or 1.28 times as controls, respectively. However, EROD activity decreased with the increases in MC doses and incubation time, with the lowest as 35% of the controls. The effect of UC on GST activity was not so obvious, with the highest as the increase in its activity by 20%. The highest induction of MC to GST activity was at a dose of 25 mg/L, 2, 5 times as that in controls. With the increases in its doses, effects of MC on GTS activity became inhibition from induction, like that on EROD activity. MC at a dose of 200 mg/L could lower the activity of GST by 18.7%. A549 cells were incubated with chrysotile fiber for 24 h firstly, and then incubated with benzo(a)pyrene to induce the activities of EROD and GST. The results showed that neither UC nor MC could affect the activity of EROD induced by benzo(a)pyrene. However, UC at a dose of 200 mg/L and MC at 100 mg/L could increase the activity of GST induced by benzo(a)pyrene. CONCLUSION: Chrysotile at different doses or its different types showed varied effects on the activities of EROD and GST in A549 cell lines, probably because of different physicochemical characteristics and surface activity of two kinds of asbestos.

Asbestos, Serpentine↗