OBJECTIVES: We propose a segmented backprojection tensor degradation feature encoding (SBP-MAC) model for motion artifact correction in dental cone beam computed tomography (CBCT) to improve the quality of the reconstructed images. METHODS: The proposed motion artifact correction model consists of a generator and a degradation encoder. The segmented limited-angle reconstructed sub-images are stacked into the tensors and used as the model input. A degradation encoder is used to extract spatially varying motion information in the tensor, and the generator's skip connection features are adaptively modulated to guide the model for correcting artifacts caused by different motion waveforms. The artifact consistency loss function was designed to simplify the learning task of the generator. RESULTS: The proposed model could effectively remove motion artifacts and improve the quality of the reconstructed images. For simulated data, the proposed model increased the peak signal-to-noise ratio by 8.28%, increased the structural similarity index measurement by 2.29%, and decreased the root mean square error by 23.84%. For real clinical data, the proposed model achieved the highest expert score of 4.4221 (against a 5-point scale), which was significantly higher than those of all the other comparison methods. CONCLUSIONS The SBP-MAC model can effectively extract spatially varying motion information in the tensors and achieve adaptive artifact correction from the tensor domain to the image domain to improve the quality of reconstructed dental CBCT images.
Cone-Beam Computed Tomography/methods* ; Artifacts ; Humans ; Motion ; Image Processing, Computer-Assisted/methods* ; Signal-To-Noise Ratio ; Algorithms

Sarcopenia is an age-related skeletal muscle degenerative disease.Physiologically aging mice are the most commonly used animal model for studying sarcopenia.As sarcopenia is characterized by decreased skeletal muscle mass and reduced muscle strength,exercise performance as a reflection of muscle function is widely used to evaluate sarcopenia.Methods of evaluating the motor function of sarcopenia mouse models are generally designed based on muscle endurance,muscle strength,coordination,and balance.The method include tests such as treadmill exhaustion,voluntary wheel use,grip strength,horse grid,bars and balance beam tests.By collating recent publications,we have systematically summarized the method used for evaluating motor function,including the tests'principles,procedures,evaluation indexes,advantages,and disadvantages.We then propose an operational program for evaluating the sarcopenia phenotype,which will be of help to researchers wishing to choose evaluation method appropriate to their specific research purposes.Further innovative technology for assessing motor function that could be instructive in the evaluation of skeletal muscle function and diagnosis of sarcopenia is summarized.

Sarcopenia is an age-related skeletal muscle degenerative disease.Physiologically aging mice are the most commonly used animal model for studying sarcopenia.As sarcopenia is characterized by decreased skeletal muscle mass and reduced muscle strength,exercise performance as a reflection of muscle function is widely used to evaluate sarcopenia.Methods of evaluating the motor function of sarcopenia mouse models are generally designed based on muscle endurance,muscle strength,coordination,and balance.The method include tests such as treadmill exhaustion,voluntary wheel use,grip strength,horse grid,bars and balance beam tests.By collating recent publications,we have systematically summarized the method used for evaluating motor function,including the tests'principles,procedures,evaluation indexes,advantages,and disadvantages.We then propose an operational program for evaluating the sarcopenia phenotype,which will be of help to researchers wishing to choose evaluation method appropriate to their specific research purposes.Further innovative technology for assessing motor function that could be instructive in the evaluation of skeletal muscle function and diagnosis of sarcopenia is summarized.

Background::Adamantinomatous craniopharyngioma (ACP) is the commonest pediatric sellar tumor. No effective drug is available and interpatient heterogeneity is prominent. This study aimed to identify distinct molecular subgroups of ACP based on the multi-omics profiles, imaging findings, and histological features, in order to predict the response to anti-inflammatory treatment and immunotherapies.Methods::Totally 142 Chinese cases diagnosed with craniopharyngiomas were profiled, including 119 ACPs and 23 papillary craniopharyngiomas. Whole-exome sequencing (151 tumors, including recurrent ones), RNA sequencing (84 tumors), and DNA methylome profiling (95 tumors) were performed. Consensus clustering and non-negative matrix factorization were used for subgrouping, and Cox regression were utilized for prognostic evaluation, respectively.Results::Three distinct molecular subgroups were identified: WNT, ImA, and ImB. The WNT subgroup showed higher Wnt/β-catenin pathway activity, with a greater number of epithelial cells and more predominantly solid tumors. The ImA and ImB subgroups had activated inflammatory and interferon response pathways, with enhanced immune cell infiltration and more predominantly cystic tumors. Mitogen-activated protein kinases (MEK/MAPK) signaling was activated only in ImA samples, while IL-6 and epithelial-mesenchymal transition biomarkers were highly expressed in the ImB group, mostly consisting of children. The degree of astrogliosis was significantly elevated in the ImA group, with severe finger-like protrusions at the invasive front of the tumor. The molecular subgrouping was an independent prognostic factor, with the WNT group having longer event-free survival than ImB (Cox, P = 0.04). ImA/ImB cases were more likely to respond to immune checkpoint blockade (ICB) therapy than the WNT group ( P <0.01). In the preliminary screening of subtyping markers, CD38 was significantly downregulated in WNT compared with ImA and ImB ( P = 0.01). Conclusions::ACP comprises three molecular subtypes with distinct imaging and histological features. The prognosis of the WNT type is better than that of the ImB group, which is more likely to benefit from the ICB treatment.

The discovery of new enzymes for poly(ethylene terephthalate) (PET) degradation has been a hot topic of research globally. Bis-(2-hydroxyethyl) terephthalate (BHET) is an intermediate compound in the degradation of PET and competes with PET for the substrate binding site of the PET-degrading enzyme, thereby inhibiting further degradation of PET. Discovery of new BHET degradation enzymes may contribute to improving the degradation efficiency of PET. In this paper, we discovered a hydrolase gene sle (ID: CP064192.1, 5085270-5086049) from Saccharothrix luteola, which can hydrolyze BHET into mono-(2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA). BHET hydrolase (Sle) was heterologously expressed in Escherichia coli using a recombinant plasmid, and the highest protein expression was achieved at a final concentration of 0.4 mmol/L of isopropyl-β-d-thiogalactoside (IPTG), an induction duration of 12 h and an induction temperature of 20 ℃. The recombinant Sle was purified by nickel affinity chromatography, anion exchange chromatography, and gel filtration chromatography, and its enzymatic properties were also characterized. The optimum temperature and pH of Sle were 35 ℃ and 8.0, and more than 80% of the enzyme activity could be maintained in the range of 25-35 ℃ and pH 7.0-9.0 and Co²⁺ could improve the enzyme activity. Sle belongs to the dienelactone hydrolase (DLH) superfamily and possesses the typical catalytic triad of the family, and the predicted catalytic sites are S129, D175, and H207. Finally, the enzyme was identified as a BHET degrading enzyme by high performance liquid chromatography (HPLC). This study provides a new enzyme resource for the efficient enzymatic degradation of PET plastics.
Actinomycetales/genetics* ; Hydrolases/metabolism* ; Phthalic Acids/chemistry* ; Polyethylene Terephthalates/metabolism*

Objective:To optimize the ultrasonic extraction process of total alkaloids from Oxytropis falcata bunge. Methods:The independent variables were solvents ratio, extracting time and ethanol concentration, and the dependent variable was content of total al-kaloids. Based on single factor tests, central composite design and response surface methodology was adopted to optimize the extraction technology. Results:The optimal extraction conditions were as follows: extracted twice with 36-fold amount of 72% ethanol ( contai-ning 1% acetic acid) at 60 ℃, and extracted 77 minutes each time. Under the above conditions, the content of total alkaloids was 2. 793 mg·g-1 with the bias ratio less than 2% when compared with the model predictions. Conclusion:Ultrasonic extraction process of total alkaloids from Oxytropis falcata Bunge optimized by central composite design and response surface method is simple, highly pre-cise, reliable and predictable.

Objective: To investigate the impact and its possible mechanism of hydrogen sulfide (H2S) on myocardial collagen remodeling in experimental rats with diabetic mellitus (DM).
Methods: Rat’s DM model was established by intraperitoneal injection of STZ at 40 mg/kg. A total of 40 SD rats were randomly divided into 4 groups:Control group, DM group, DM+NaHS group, in which NaHS worked as exogenous donor of H2S and NaHS control group. n=10 in each group, all animals were treated for 8 weeks. The cardiac collagen deposition was observed by Masson staining, protein expressions of cardiac collagen types I, III, IV and transforming growth factorβ1 (TGF-β1), connective tissue growth factor (CTGF) were examined by Western blot analysis.
Results: Compared with Control group, DM group showed increased protein expressions of cardiac collagen types I and III, up-regulated expressions of TGF-β1 and CTGF, P<0.05;while the expressions of collagen type IV were similar between 2 groups. Compared with DM group, DM+NaHS group presented reduced cardiac collagen expression, decreased expression of collagen types I and III, down-regulated expressions of TGF-β1 and CTGF, P<0.05;while the expressions of collagen type IV were similar between 2 groups.
Conclusion: H2S may improve the myocardial collagen remodeling in experimental DM rats, the mechanism might be related to the down-regulation of TGF-β1 and CTGF expression.

Objective To investigate the situation of human papillomavirus (HPV) infection and the distribution of HPV genotypes among women attending hospital in Meizhou,Guangdong province.Methods Flow-through hybridization and gene chip technique was used to detect HPV in cervical exfoliated cell specimens collected from 24 450 women for HPV screening in Department of Gynecology,Meizhou People's Hospital,Meizhou Hospital Affiliated to Sun Yat-sen University,and then the situation of HPV infection and distribution of HPV genotypes were analyzed.Results Among 24 450 female exfoliated cell specimens,3 922 were found to be positive for HPV infection,with the total infection rate of 16.04％.Among 3 922 samples,the top three high-risk subtypes of HPV were HPV-16 (30.37％),HPV-52 (17.77％) and HPV-58 (15.53％),the majority of low-risk HPV was HPV-CP8304 (5.61％).The positivity of various HPV types peaked among 30-50 years old.The differences of the HPV positive rates in different age groups was statistical significance (P ＜ 0.001).Conclusions The majority of women attending hospital detected with HPV-16 in Meizhou and the positivity of various HPV types peaked among women aged 30-50 years.Genotyping of HPV was meaningful for preventing and treating cervical cancer.

Objective To explore the effects of hydrogen sulfide (H2S) on myocardial fibrosis and expressions of MAPK1/3 and MMP-8 in diabetic rats. Methods Forty adult male SD rats were randomized into 4 groups, namely the control group, diabetes mellitus group (STZ group), diabetes mellitus with H2S treatment group (STZ+H2S group), and normal rats with H2S treatment group (H2S group). Diabetes was induced by intraperitoneal injections of 40 mg/kg streptozotocin (STZ). The rats in the control group received daily intraperitoneal injections of saline, and those in STZ+H2S group and H2S group were given NaHS (100μmol/kg) injections. After 8 weeks, the pathologies of cardiac fibrosis were examined with HE staining, and the expressions of collagen I, MAPK1/3 and MMP-8 were analyzed with Western blotting. Results Compared with the control group, the diabetic rats showed increased collagen content and obvious interstitial fibrosis in the myocardial tissue with significantly increased expression levels of collagen I, MAPK1/3 and MMP-8 (P<0.05); all these changes were obviously reversed by treatment with H2S (P<0.05). Collagen I, MAPK1/3 and MMP-8 expression levels and the degree of myocardial fibrosis were comparable between H2S group and control group (P>0.05). Conclusion Hydrogen sulfide can attenuate cardiac fibrosis in diabetic rats, and the mechanism may involve the inhibition of MAPK1/3/MMP-8 signal pathway.

Objective To explore the effects of hydrogen sulfide (H2S) on myocardial fibrosis and expressions of MAPK1/3 and MMP-8 in diabetic rats. Methods Forty adult male SD rats were randomized into 4 groups, namely the control group, diabetes mellitus group (STZ group), diabetes mellitus with H2S treatment group (STZ+H2S group), and normal rats with H2S treatment group (H2S group). Diabetes was induced by intraperitoneal injections of 40 mg/kg streptozotocin (STZ). The rats in the control group received daily intraperitoneal injections of saline, and those in STZ+H2S group and H2S group were given NaHS (100μmol/kg) injections. After 8 weeks, the pathologies of cardiac fibrosis were examined with HE staining, and the expressions of collagen I, MAPK1/3 and MMP-8 were analyzed with Western blotting. Results Compared with the control group, the diabetic rats showed increased collagen content and obvious interstitial fibrosis in the myocardial tissue with significantly increased expression levels of collagen I, MAPK1/3 and MMP-8 (P<0.05); all these changes were obviously reversed by treatment with H2S (P<0.05). Collagen I, MAPK1/3 and MMP-8 expression levels and the degree of myocardial fibrosis were comparable between H2S group and control group (P>0.05). Conclusion Hydrogen sulfide can attenuate cardiac fibrosis in diabetic rats, and the mechanism may involve the inhibition of MAPK1/3/MMP-8 signal pathway.