Lactate-upregulated NADPH-dependent NOX4 expression via HCAR1/PI3K pathway contributes to ROS-induced osteoarthritis chondrocyte damage.

Increasing evidence shows that metabolic factors are involved in the pathological process of osteoarthritis (OA). Lactate has been shown to contribute to the onset and progression of diseases. While whether lactate is involved in the pathogenesis of OA through impaired chondrocyte function and its mechanism remains unclear. This study confirmed that serum lactate levels were elevated in OA patients compared to healthy controls and were positively correlated with synovial fluid lactate levels, which were also correlated with fasting blood glucose, high-density lipoprotein, triglyceride. Lactate treatment could up-regulate expressions of the lactate receptor hydroxy-carboxylic acid receptor 1 (HCAR1) and lactate transporters in human chondrocytes. We demonstrated the dual role of lactate, which as a metabolite increased NADPH levels by shunting glucose metabolism to the pentose phosphate pathway, and as a signaling molecule up-regulated NADPH oxidase 4 (NOX4) via activating PI3K/Akt signaling pathway through receptor HCAR1. Particularly, lactate could promote reactive oxygen species (ROS) generation and chondrocyte damage, which was attenuated by pre-treatment with the NOX4 inhibitor GLX351322. We also confirmed that lactate could increase expression of catabolic enzymes (MMP-3/13, ADAMTS-4), reduce the synthesis of type II collagen, promote expression of inflammatory cytokines (IL-6, CCL-3/4), and induce cellular hypertrophy and aging in chondrocytes. Subsequently, we showed that chondrocyte damage mediated by lactate could be reversed by pre-treatment with N-Acetyl-l-cysteine (NAC, ROS scavenger). Finally, we further verified in vivo that intra-articular injection of lactate in Sprague Dawley (SD) rat models could damage cartilage and exacerbate the progression of OA models that could be countered by the NOX4 inhibitor GLX351322. Our study highlights the involvement of lactate as a metabolic factor in the OA process, providing a theoretical basis for potential metabolic therapies of OA in the future.

Preliminary application of a 3D-printed track-guided precise drug delivery device for the sinuses after endoscopic sinus surgery.

BACKGROUND: Conventional treatment for eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP) is usually limited; consequently, relapses occur frequently, accurate local drug delivery is currently a research area of major interest. METHODS: Based on postoperative nasal sinus computed tomography (CT) images, the 3D printing technique was used to design and fabricate a precise track-guided sinus drug delivery device. The control group was treated with glucocorticoids by nasal spray for 1 year according to the conventional method, while the experimental group received topical nasal glucocorticoids using the 3D-printed track-guided precise sinus drug delivery device for 1 year. Scores on the Sino-Nasal Outcome Test (SNOT-22) scale and the Lund-Kennedy nasal endoscopic scale during reexamination at 1 month, 3 months, 6 months, and 1 year after the operation were used as the basis for evaluation. RESULTS: The follow-up duration was 12 months or more following endoscopic sinus surgery (ESS) with neosinus cavity formation. The two groups showed significant differences in SNOT-22 scores and nasal polyp Lund-Kennedy subscores at 3 months, 6 months, and 1 year (p < 0.001) and no differences in plasma cortisol at 6 months and 1 year (p > 0.05). CONCLUSION: Local drug administration using our 3D-printed precise sinus drug delivery device is superior to conventional nasal cavity administration in controlling eCRS recurrence.

Time Series Forecasting of Motor Bearing Vibration Based on Informer.

Electric energy, as an economical and clean energy, plays a significant role in the development of science and technology and the economy. The motor is the core equipment of the power station; therefore, monitoring the motor vibration and predicting time series of the bearing vibration can effectively avoid hazards such as bearing heating and reduce energy consumption. Time series forecasting methods of motor bearing vibration based on sliding window forecasting, such as CNN, LSTM, etc., have the problem of error accumulation, and the longer the time-series forecasting, the larger the error. In order to solve the problem of error accumulation caused by the conventional methods of time series forecasting of motor bearing vibration, this paper innovatively introduces Informer into time series forecasting of motor bearing vibration. Based on Transformer, Informer introduces ProbSparse self-attention and self-attention distilling, and applies random search to optimize the model parameters to reduce the error accumulation in forecasting, achieve the optimization of time and space complexity and improve the model forecasting. Comparing the forecasting results of Informer and those of other forecasting models in three publicly available datasets, it is verified that Informer has excellent performance in time series forecasting of motor bearing vibration and the forecasting results reach 10-2∼10-6.

Comprehensive Analysis of the COVID-19: Based on the Social-Related Indexes From NUMBEO.

Background: The COVID-19 has been spreading globally since 2019 and causes serious damage to the whole society. A macro perspective study to explore the changes of some social-related indexes of different countries is meaningful. Methods: We collected nine social-related indexes and the score of COVID-safety-assessment. Data analysis is carried out using three time series models. In particular, a prediction-correction procedure was employed to explore the impact of the pandemic on the indexes of developed and developing countries. Results: It shows that COVID-19 epidemic has an impact on the life of residents in various aspects, specifically in quality of life, purchasing power, and safety. Cluster analysis and bivariate statistical analysis further indicate that indexes affected by the pandemic in developed and developing countries are different. Conclusion: This pandemic has altered the lives of residents in many ways. Our further research shows that the impacts of social-related indexes in developed and developing countries are different, which is bounded up with their epidemic severity and control measures. On the other hand, the climate is crucial for the control of COVID-19. Consequently, exploring the changes of social-related indexes is significative, and it is conducive to provide targeted governance strategies for various countries. Our article will contribute to countries with different levels of development pay more attention to social changes and take timely and effective measures to adjust social changes while trying to control this pandemic.

Thrombocytopenia Is an Independent Risk Factor for the Prognosis of Thrombotic Microangiopathy in Chinese Patients With Systemic Lupus Erythematosus.

Objectives: This study aims to describe clinical characteristics and outcome of thrombotic microangiopathy (TMA) in Chinese patients with systemic lupus erythematosus (SLE), and investigate the risk factors. Methods: We conducted a retrospective single-center cohort and enrolled patients of TMA associated with SLE between January 2015 and December 2018. Demographic characteristics, clinical features, laboratory profiles, therapeutic strategies, and outcomes were collected. The risk factors of TMA in patients with SLE for mortality using multivariate analysis were estimated. Results: A total of 119 patients with a diagnosis of TMA were enrolled within the study period in our center, and SLE was found in 72 (60.5%) patients. The mean age was 29.2 ± 10.1 and 65 (92.3%) were women. Only 15 patients were found with definite causes, the other 57 cases remained with unclear reasons. Sixty-two patients got improved, while 10 patients died after treatment (mortality rate: 13.9%). Compared with the survival group, the deceased group had a higher prevalence of neuropsychiatric manifestations, infection with two or more sites, increased levels of C-reaction protein (CRP) and D-Dimer, and decreased platelet count. Multivariate analysis showed that the decrease of platelet count is the independent risk factor for in-hospital mortality for TMA in patients with SLE. The receiver operating characteristic (ROC) curve analysis displayed that a cutoff value of <18 × 109/L for platelet count could significantly increase the risk of death. Conclusions: Thrombotic microangiopathy often occurs in patients with active SLE with high mortality (13.9%), and thrombocytopenia, especially when the platelet count is lower than 18 × 109/L, is the risk factor for death.

Progressive compressive myelopathy induced by a rare primary isolated thoracic vertebral hydatid cyst: A case report.

RATIONALE: Hydatid cyst is a disease caused by the larvae of Echinococcus spp. The larvae often reside in the liver, lungs, and brain. Occasionally, a primary isolated thoracic vertebral hydatid cyst is reported to cause severe complications. Various diseases may lead to the development of progressive compressive myelopathy. Herein, we report a rare case of a primary isolated thoracic vertebral hydatid cyst with compressive myelopathy. PATIENT CONCERNS: A 57-year-old female had numbness and weakness in the lower limbs for a span of 3-months. DIAGNOSIS: Thoracic magnetic resonance imaging (MRI) showed that an isolated mass was observed in the T5 vertebral body, which compressed the spinal cord. The diagnosis was confirmed after surgical excision, and Echinococcus granulosus was found to be the etiologic factor. INTERVENTIONS: The patient underwent laminectomy with no complications. OUTCOMES: After surgical decompression, the patient made slow and measurable progress. While relatively rare in the non-pastoral area, the primary isolated thoracic vertebral column hydatid cyst may be considered as a possible etiology of atypical extradural spinal compression. LESSONS: This case illustrates the complexity of spinal echinococcosis manifestations and the necessity of an interdisciplinary approach.

One-step purification and immobilization of recombinant proteins using SpyTag/SpyCatcher chemistry.

Based on the specific and spontaneous formation of isopeptide bonds by SpyCatcher/SpyTag, we have developed a one-step method for purification and immobilization of recombinant proteins. The procedure is to immobilize SpyCatcher on glyoxyl agarose gels, and then the SpyCatcher immobilisate can be used to immobilize the SpyTag-fused protein in the crude extract selectively. A mutant of SpyCatcher (mSC), in which a peptide (LysGlyLysGlyLysGly) was added to the C-terminus of SpyCatcher and three lysine residues around the SpyTag/SpyCatcher binding domain were replaced with arginine, was designed to improve the attachment of SpyCatcher to the support. Compared with wild-type SpyCatcher, mSC can be immobilized on the glyoxyl-agarose support more efficiently, which enables the obtained mSC derivative a high binding capacity of the SpyTag-fused protein. The results showed that the target proteins in the crude enzyme extract were purified and immobilized in one step, and the thermal stability of the immobilized target proteins was also remarkably improved.

Primary renal synovial sarcoma: A case report.

RATIONALE: Synovial sarcoma (SS) is a malignant neoplasm that arises from soft tissues proximal to the joints. It occurs primarily at the major joints of the extremities, but may also occur in the deep soft tissues around the joints. While primary renal synovial sarcoma (PRSS) is extremely rare, it is important to have a better understanding of their imaging and clinical features to establish an effective treatment plan. Correct identification of PRSS is also useful for treating renal neoplasms. PATIENT'S CONCERNS: A 56-year-old Chinese man was admitted to our hospital due to moderate, paroxysmal left-sided loin pain. DIAGNOSIS: Renal enhanced computed tomography (CT) scanning showed a relatively hypovascular lesion with calcification in the left kidney. A radical nephrectomy was performed in the left kidney. Postoperative pathology indicated SS with necrosis. The immunohistochemical findings were as follows: 34ßE12 (Epithelium+), Bcl-2(+), CD99(+), CK-pan((Epithelium+), EMA(Epithelium+), Ki-67(+60%), and Vimentin(+), CD34(-). INTERVENTIONS: The patient underwent radical left nephrectomy with no complications. OUTCOMES: After discharge, a close review for 3 months showed no evidence of recurrence. LESSONS: PRSS should be considered for the differential diagnosis of renal hypovascular tumors. When problems arise in distinguishing renal hypovascular tumors, surgical pathology is helpful in the final diagnosis and further treatment of the disease.

Evaluation of the effects of applying the ventricular care bundle (VCB) method for reducing ventilator-associated pneumonia (VAP) in the intensive care unit of a general Chinese tertiary hospital.

BACKGROUND: Ventilator-associated pneumonia (VAP) is a severe complication that occurs within patients who must use ventilators in the intensive care unit (ICU). Ventilator care bundles (VCB) have been applied across many developed regions and have produced positive results in controlling VAP. In this study, we report on the implementation and effects of using VCBs to manage VAP in a general tertiary hospital in the Inner Mongolia Autonomous Region of China. METHODS: A targeted surveillance method was used to survey all the patients (n=4,716) in the ICU from June 1, 2017 to May 31, 2019. Patients from June 1, 2017 to May 31, 2018, and June 1, 2018, to May 31, 2019, were respectively divided into 2 groups: the control group (2,029 patients) and intervention group (2,687 patients). These dates were selected because VCB was implemented from June 1, 2018, in our institution. The variables that were associated with VCB and observed were the head-of-bed elevation, oral care, maintenance of the pressure for the cuff of the endotracheal tube, aspiration of subglottic secretion, daily sedation vacation protocol, daily extubation assessment results, and hand hygiene. After collecting the data, the compliance of VCB, ventilator use ratio, and the incidence rate of VAP in these 2 groups were compared. RESULTS: We observed that compliance with all of the intervention measures for VCB improved results in the intervention group compared to the control. Furthermore, the compliance rate of hand hygiene increased from 71.99% to 91.97%, and the head-of-bed elevation of 30°-45° increased from 62.02% to 85.96%. All differences between these two groups were statistically significant, according to the χ 2 -test. The ventilator use ratio was statistically and significantly lower in the intervention group (34.86%) compared to the control group (40.29%) (χ 2 =95.513, P<0.001). The incidence rate of VAP was statistically and significantly lower in the intervention group (13.70‰) compared to the control group (18.85‰) (χ 2 =5.471, P=0.019). CONCLUSIONS: Our results show that VCB prevents VAP. Therefore, personnel training, clinical supervision, and surveillance feedback could promote a reduction in intervention measures.

Drug resistance of healthcare-associated pathogenic bacteria and carbapenem-resistant Acinetobacter baumannii homology in the general intensive care unit.

BACKGROUND: The objective of this study was to understand the distribution and drug resistance of healthcare-associated infection (HAI) pathogens in an intensive care unit (ICU) of a general tertiary hospital in Inner Mongolia, and to classify carbapenem-resistant Acinetobacter baumannii (CR-AB) in ICU patients and environmental samples. Additionally, this study aimed to provide scientific evidence for the use of clinical antibiotics and effective prevention and control measures for CR-AB outbreak. METHODS: The distribution and drug resistance of pathogens isolated from patient's samples in the ICU of 12 Hospitals from January to May 2019 were retrospectively analyzed. Meanwhile, CR-AB isolated from patients and environmental samples were collected and classified by pulsed-field gel electrophoresis (PFGE). RESULTS: The pathogens isolated from ICU samples, mainly Gram-negative bacteria (63.07%), were CR-AB, Klebsiella pneumoniae, and Pseudomonas aeruginosa; the main Gram-positive bacteria (22.13%) were Enterococcus faecium and Staphylococcus aureus; and fungi accounted for the remaining (14.80%). The samples mainly came from sputum (41.09%). Among non-fermenting bacteria, the resistance rates of CRAB to piperacillin, piperacillin/tazobactam, and other treatments were higher than those of Pseudomonas aeruginosa (P<0.05). Meanwhile, the resistance rates to ampicillin/sulbactam and compound sulfamethoxazole were lower than those of Pseudomonas aeruginosa (P<0.05). The resistance rates of Klebsiella pneumoniae to piperacillin/tazobactam, ceftazidime, and others were higher than those of Escherichia coli (P<0.05). Among Gram-positive bacteria, the resistance rates of Enterococcus faecium to erythromycin, clindamycin, and other treatment were higher than those of Staphylococcus aureus (P<0.05). A total of 62 bands were obtained from 63 strains of CR-AB by electrophoresis. Also, 16 clusters (A-P) were obtained with a 74% similarity coefficient, among which K, L, and N types (more than 9 strains) were more common. CONCLUSIONS: Gram-negative bacteria were the primary pathogens of HAI in the ICU, and their drug resistance was serious. There is homology in the PFGE typing of CR-AB. Therefore, hospitals should strengthen the surveillance of drug-resistant pathogenic bacteria. Additionally, further cleaning and disinfection measures are needed to improve environmental hygiene and prevent outbreaks of HAI.

Healthcare-associated infection prevention and control management in a tertiary hospital and an overall evaluation.

BACKGROUND: Healthcare-associated infection (HAI) is a crucial factor influencing medical quality. Studies about HAI management situations are rare, especially for the Inner Mongolia region of China. Therefore, this study aimed to investigate management procedures and the overall evaluation of HAI in order to inform HAI management improvement more scientifically. METHODS: A questionnaire was used to investigate HAI-related prevention and control indicators in tertiary hospitals in the Inner Mongolia region from July 2018 to June 2019. RESULTS: The survey showed that the mean incidence rate of HAI was 3.79%. The mean rate of hand hygiene compliance of healthcare workers (HCWs), inpatient's antibiotics-use rate, and the detection of the antibiotic ratio before therapy was 54.34%, 34.33%, and 25.40%, respectively. The mean of the surgical site infection (SSI) rate of the level I incision and the preventive antibiotics-use ratio of the level I incision was 1.31% and 28.89%, respectively. The mean of the multi-drug resistant organism (MDRO) infection rate was 0.40% and the mean of the MDRO detection rate was 18.55%. The mean of the central line-associated bloodstream infection rate was 2.24%, the ventilator-associated pneumonia (VAP) rate was 11.17%, and the catheter-associated urinary tract infection (CAUTI) rate was 1.95‰. As for the overall evaluation, 19 (35.85%) hospitals had a bad grade, 18 (33.96%) hospitals had a medium grade, and 16 (30.19%) hospitals had a good grade. CONCLUSIONS: The incidence rate of HAI in tertiary hospitals in the Inner Mongolia region is higher than the national level. Also, the overall evaluation of bad-grade hospitals and their deficiencies should be used as an example to improve the HAI management level.

Hemangioblastoma arising from duramater: Case report.

RATIONALE: Hemangioblastoma (HB) is a benign tumor that is typically located in the subtentorial region of the brain. HB that originates from dura mater is extremely rare. PATIENT CONCERNS: Herein, we reported a single case of a patient who presented with dizziness and headache lasting for 1 year that progressively aggravated within 1 month. DIAGNOSIS: After admission, the patient underwent head magnetic resonance (MR); a nodular long T1-T2 signal was found on the right side of parietal falx cerebri; the lesion appeared with high intensity on FLAIR and DWI, and with isointensity on ADC map. In addition, significant homogeneous enhancements were observed on the enhanced scan. According to clinical and imaging features, the lesion was diagnosed as meningioma. However, after performing tumor resection by craniotomy, the diagnosis of HB is clear. Additional pathological examination data were found: Ki-67(+1%), NSE(-), CD31(+), CD34(+), CD56(+), S-100(-), α-inhibin(+), Vimentin(-), EGFR-), GFAP(-), CK-pan(-), EMA(-), PR(-). INTERVENTIONS: The mass with abundant blood supply was removed. OUTCOMES: Ten days after operation, the patient was discharged from hospital and no signs of recurrence were observed three months later. LESSONS: To sum up, obvious high signal intensity in T2WI sequence and homogeneous enhancement are main characteristics that differentiate dural hemangioblastoma from meningioma lesion.

SpyTag/SpyCatcher cyclization enhances the thermostability and organic solvent tolerance of L-phenylalanine aldolase.

OBJECTIVES: To improve the thermostability and organic solvent tolerance of L-phenylserine aldolase, the in vivo SpyTag/SpyCatcher cyclization strategy was applied in this work. RESULTS: The in vivo cyclization of L-phenylserine aldolase was achieved by fusing the tags of SpyCatcher and SpyTag to the N- and C-termini of the enzyme, respectively. The kcat values and the circular dichroism spectra of the linear and cyclized LPAs are very similar, indicating that the cyclized LPA can be folded appropriately like the wild type. The cyclized enzyme has better thermostability and organic solvent tolerance than does the wild type. The half-life of L-phenylserine aldolase after cyclization was increased by 8.3 times at 70 °C, and the T50 also increased from 56.8 to 67.1 °C. The cyclized enzyme showed a remarkably higher tolerance to organic solvents (e.g., methanol, ethanol and acetone). CONCLUSIONS: These results suggest that the in vivo cyclization using SpyTag/SpyCatcher is an effective strategy to improve the stability of enzymes, which potentially could be applied in industrial bioconversion.

Intraperitoneal administration of the globular adiponectin gene ameliorates diabetic nephropathy in Wistar rats.

The present study investigated the potential effects of the long-term expression of exogenous adiponectin (ADPN) on normal and diabetic kidneys. Type 2 diabetes mellitus models were induced by high-lipid and high-sucrose feeding plus intraperitoneal injection of streptozotocin. The recombinant plasmid pIRES2-EGFP-gAd, which is able to co-express globular ADPN (gAd) and enhanced green fluorescent protein (EGFP), was intraperitoneally injected into rat models mediated by Lipofectamine. In total, 32 Wistar rats were randomly assigned into four groups: the normal control group, the diabetes group, the diabetes group treated with pIRES2-EGFP-gAd and the diabetes group treated with pIRES2-EGFP. After 12 weeks, serum biochemistry and urine albumin levels were measured. The kidneys were collected to assess the generation of reactive oxygen species (ROS) and the renal pathological changes were observed by light microcopy. The protein expression of endothelial nitric oxide synthase (eNOS), transforming growth factor-ß1 (TGF-ß1) and phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) were determined by an immunohistochemical staining method and western blot analysis. Intraperitoneal injection of the human gAd gene via Lipofectamine resulted in abundant ADPN protein in the kidney. In the diabetic rats, the delivery of the exogenous gAd gene ameliorated the progression of diabetic nephropathy (DN). ADPN attenuated urine albumin excretion in the diabetic rats. ADPN also mitigated glomerular mesangial expansion, reduced the generation of ROS and prevented interstitial fibrosis. In addition, the expression of gAd inhibited the renal expression of TGF-ß1, promoted the protein expression of eNOS and activated the opening of the AMPK signaling pathway in the renal tissues of the diabetic rats. Despite the effects of ADPN on DN being controversial, these observations indicate that the supplementation of ADPN is beneficial in ameliorating DN in rats.

Adiponectin inhibits the generation of reactive oxygen species induced by high glucose and promotes endothelial NO synthase formation in human mesangial cells.

The aim of this study was to investigate the effects of adiponectin (ADPN) on high glucose (HG)-induced reactive oxygen species (ROS) and the formation of endothelial nitric oxide (NO) synthase (eNOS) in human glomerular mesangial cells (HMCs), as well as to determine which signaling pathways are modulated by ADPN and the mechanisms involved. HMCs cultured in vitro were randomly divided into 4 groups: the control, HG, HG + globular adiponectin (gAd) and HG + gAd + adenine arabinoside (AraA). The generation of ROS was detected using a fluorescent probe. The mRNA expression and protein levels of eNOS were measured by RT-PCR and western blot analysis, respectively. The phosphorylation of AMP-activated protein kinase (AMPK) was assessed by western blot analysis. HMCs treated with ADPN revealed the time-dependent phosphorylation of AMPK. The treatment of HMCs with HG resulted in increased release of ROS and decreased expression of eNOS compared to the control group (p<0.05). Cells treated with ADPN showed a decrease in HG-induced ROS (p<0.05) and an upregulated eNOS expression. The effects of gAd were partly blocked by the AMPK inhibitor, AraA. The results from the present study show that ADPN inhibits the generation of HG-induced ROS in HMCs; it also stimulates eNOS activity, which has a protective effect. The mechanism partly occurs through the stimulation of the AMPK signaling pathway.

[Renoprotective effect of adiponectin through an antioxidant mechanism in streptozotocin- induced diabetic rats].

OBJECTIVE: To investigate the renoprotective effect of adiponectin in streptozotocin (STz)-induced diabetic rats and explore its association with oxidation stress. METHODS: Type 2 diabetes mellitus was induced in rats by high-lipids and high-sucrose feeding and intraperitoneal STZ injection. The recombinant plasmid pIRES2-EGFP-gAd expressing globular adiponectin was intraperitoneally injected in the rats mediated by liposome. Thirty-two Wistar rats were randomized into 4 groups, namely the normal control group (NC), diabetic group without any therapy (DM), diabetic group treated with pIRES2-EGFP-gAd (DA) and diabetic group treated with pIRES2-EGFP (DP). After the corresponding treatments for 8 weeks, the blood glucose, HbA1c and urine albumin excretion rate (UAER) were measured, and the kidneys were collected to determine the production of reactive oxygen species (ROS) and assess renal pathologies. Immunohistochemistry and Western blot were employed to determine the protein levels of endothelial nitric oxide synthesis (eNOS) and phosphorylated AMP-activated protein kinase (pAMPK). RESULTS: UAER and ROS production increased significantly in DM group as compared with that in the control group (P<0.05), while no significant differences were found in UARE among the DM, DA, and DP groups (P>0.05). Blood glucose level, HbA1c and ROS were significantly decreased in DA group in comparison with those in DM group (P<0.05). Glomerular hypetrophy, mesangial expansion, basal membrane thickening, tubular epithelial cells cavitation and exfoliation, and mononuclear lymphocyte infiltration occurred in DM group, while these changes were ameliorated in gAd transfection group. The renal expression levels of eNOS and p-AMPK proteins in DM group were significantly lower than those in the control group (P<0.05) and gAd transfection group (P<0.05). CONCLUSIONS: The renoprotective effect of adiponectin may be at least partially mediated by the activation of the AMPK signaling passway, ROS production inhibition, relief of the oxidative stress, and up-regulation of eNOS expression in the renal tissue of diabetic rats.

[Edge detection and modeling in frontal facial contour image for plastic surgery].

OBJECTIVE: To find a new method for edge detection and modeling in frontal facial contour image. METHODS: Searching circle-based edge detection algorithm was developed on the basis of Sobel edge detector. Apriori knowledge of the facial contour and searching limitations as the minimum curvature radius, concave-convex property, and maximum edge disconnected distance were used to detect the edge of frontal facial contour. The frontal facial contour model was established with least squares curve fitting methods, and the relationship between the model rank and model precision was analyzed. RESULTS: The edge detected by the new method was consistent with the actual edge of the facial contour and the irrelevant edge was well eliminated. Variation of the 2,4,10 time models from the actual image were compared, which identified the 10 time model as the best one. CONCLUSION: The effectiveness and practicability of this new method for edge detection and modeling has been tested, which provides a theoretic basis for designing facial contouring image system.