[Constructing the Bayesian network models to explore the factors related to glomerular and tubular injury]

Objective: To construct Bayesian network (BN) models to explore the factors related to glomerular injury (GI) and tubular injury (TI). Methods: A cross-sectional study was carried out. From April to November 2019, Shanxi Provincial People's Hospital performed an opportunistic screening for chronic kidney disease in 10 counties of Shanxi Province. The general data and laboratory results of blood and urine samples were collected. Chi-square test and logistic regression were used to explore the related factors of GI and TI, which were included in the construction of BN models with max-min hill-climbing (MMHC) algorithm. Results: A total of 12 269 participants were included, there were 5 198 males and 7 071 females, with a median age of 58 (40-91) years. The prevalence of GI and TI was 12.7% (1 561/12 269) and 11.6% (1 425/12 269), respectively. The BN model consisted of 8 nodes and 10 edges for GI, and 11 nodes and 17 edges for TI, respectively. BN models showed that age and glycated hemoglobin were direct related factors for GI, while gender and fasting blood glucose were indirect related factors for GI. Age, gender, fasting blood glucose and glycosylated hemoglobin were direct related factors for TI. Additionally, the area under the receiver operating characteristic curve (AUC) was 0.761 (95%CI: 0.746-0.777) and 0.753 (95%CI: 0.736-0.769) for GI and TI BN models, respectively. Conclusions: BN models allow for identifying the complex network relationships among the factors related to GI and TI. Meanwhile, Bayesian risk reasoning can provide reference value for the clinical prevention of GI and TI.

[Establishment of a prognostic model for non-nephrotic membranous nephropathy based on unbalanced data]

Objective: To explore the construction of a machine learning model based on unbalanced data to predict the progression of non-nephrotic membranous nephropathy. Methods: The clinical and pathological data of patients diagnosed with non-nephrotic membranous nephropathy by renal biopsy in Shanxi People's Hospital from January 2018 to December 2021 were retrospectively analyzed.The prediction models were constructed based on logistic regression, support vector machine (SVM) and light gradient boosting machine (lightGBM), respectively. The mixed sampling technology was used to process the unbalanced data, and the area under the receiver operating characteristic curve (AUC) was used to evaluate the predictive performance of the models. Finally, Shapley additive explanation (SHAP) was used to interpret the results of the optimal prediction model. Results: A total of 148 patients were included in the study, including 84 males and 64 females, with a mean age of (47.2±12.5) years. The follow-up time [M(Q₁, Q₃)] was 14(7, 20) months. Twenty-three patients (15.5%) achieved the renal end-point event in the study. The SVM model had the highest AUC (0.868, 95%CI: 0.813-0.925), followed by logistic regression (AUC=0.865, 95%CI: 0.755-0.899) and lightGBM (AUC=0.791, 95%CI: 0.690-0.882). The feature recursive elimination cross validation (RFECV) method based on random forest (RF) and the SHAP plot based on the SVM model showed that immunohistochemistry IgG, total protein (TP), anti-phospholipase A2 receptor (anti-PLA2R), blood chloride and D-Dimer were risk factors affecting the progress of non-nephrotic membranous nephropathy. Moreover, patients with high immunohistochemistry IgG, anti-PLA2R and D-Dimer had an increased risk of achieving the renal end-point event. Conclusion: The SVM model established in this study can effectively predict the progress of non-nephrotic membranous nephropathy, and provide a new method for the early identification of high-risk patients and precision therapy.

[Whole-course management strategies for gastroesophageal reflux disease: an evidence mapping study based on clinical practice guidelines]

Gastroesophageal reflux disease (GERD) is one of the most common digestive diseases with high incidence, complicated clinical symptoms, difficulties in standard treatment, and heavy medical burden. At present, some GERD-relevant clinical practice guidelines (CPGs) have been issued by different countries and academic organizations, but some recommendations were inconsistent, which has caused some problems for the current clinical whole-course management of GERD. To summarize the relevant evidence among the CPGs on GERD and formulate the whole- course management strategies, we included GERD-relevant CPGs published or updated after 2010 by searching websites of guidelines, relevant professional societies, and electronic databases. We extracted the recommendations and summarized the evidence from the aspects of symptoms, epidemiology, diagnosis and treatment, which was presented in the form of evidence mapping. We included 24 CPGs, including three in Chinese and 21 in English. The clinical practice management strategies of GERD were formulated based on the evidence from the aspects of clinical symptoms, diagnostic methods, medical treatment, anti-reflux surgery and endoscopic treatment, psychological treatment, and traditional Chinese medicine treatment.

[Efficacy and safety of various doses of hybutimibe monotherapy or in combination with atorvastatin for primary hypercholesterolemia: a multicenter, randomized, double-blind, double-dummy, parallel-controlled phase Ⅲ clinical trial]

Objective: To evaluate the efficacy and safety of hybutimibe monotherapy or in combination with atorvastatin in the treatment of primary hypercholesterolemia. Methods: This was a multicenter, randomized, double-blind, double-dummy, parallel-controlled phase Ⅲ clinical trial of patients with untreated primary hypercholesterolemia from 41 centers in China between August 2015 and April 2019. Patients were randomly assigned, at a ratio of 1∶1∶1∶1∶1∶1, to the atorvastatin 10 mg group (group A), hybutimibe 20 mg group (group B), hybutimibe 20 mg plus atorvastatin 10 mg group (group C), hybutimibe 10 mg group (group D), hybutimibe 10 mg plus atorvastatin 10 mg group (group E), and placebo group (group F). After a dietary run-in period for at least 4 weeks, all patients were administered orally once a day according to their groups. The treatment period was 12 weeks after the first dose of the study drug, and efficacy and safety were evaluated at weeks 2, 4, 8, and 12. After the treatment period, patients voluntarily entered the long-term safety evaluation period and continued the assigned treatment (those in group F were randomly assigned to group B or D), with 40 weeks' observation. The primary endpoint was the percent change in low density lipoprotein cholesterol (LDL-C) from baseline at week 12. Secondary endpoints included the percent changes in high density lipoprotein cholesterol (HDL-C), triglyceride (TG), apolipoprotein B (Apo B) at week 12 and changes of the four above-mentioned lipid indicators at weeks 18, 24, 38, and 52. Safety was evaluated during the whole treatment period. Results: Totally, 727 patients were included in the treatment period with a mean age of (55.0±9.3) years old, including 253 males. No statistical differences were observed among the groups in demographics, comorbidities, and baseline blood lipid levels. At week 12, the percent changes in LDL-C were significantly different among groups A to F (all P<0.01). Compared to atorvastatin alone, hybutimibe combined with atorvastatin could further improve LDL-C, TG, and Apo B (all P<0.05). Furthermore, there was no significant difference in percent changes in LDL-C at week 12 between group C and group E (P=0.991 7). During the long-term evaluation period, there were intergroup statistical differences in changes of LDL-C, TG and Apo B at 18, 24, 38, and 52 weeks from baseline among the statins group (group A), hybutimibe group (groups B, D, and F), and combination group (groups C and E) (all P<0.01), with the best effect observed in the combination group. The incidence of adverse events was 64.2% in the statins group, 61.7% in the hybutimibe group, and 71.0% in the combination group during the long-term evaluation period. No treatment-related serious adverse events or adverse events leading to death occurred during the 52-week study period. Conclusions: Hybutimibe combined with atorvastatin showed confirmatory efficacy in patients with untreated primary hypercholesterolemia, which could further enhance the efficacy on the basis of atorvastatin monotherapy, with a good overall safety profile.

Scaphoid Fracture Detection by Using Convolutional Neural Network

Scaphoid fractures frequently appear in injury radiograph, but approximately 20% are occult. While there are few studies in the fracture detection of X-ray scaphoid images, their effectiveness is insignificant in detecting the scaphoid fractures. Traditional image processing technology had been applied to segment interesting areas of X-ray images, but it always suffered from the requirements of manual intervention and a large amount of computational time. To date, the models of convolutional neural networks have been widely applied to medical image recognition; thus, this study proposed a two-stage convolutional neural network to detect scaphoid fractures. In the first stage, the scaphoid bone is separated from the X-ray image using the Faster R-CNN network. The second stage uses the ResNet model as the backbone for feature extraction, and uses the feature pyramid network and the convolutional block attention module to develop the detection and classification models for scaphoid fractures. Various metrics such as recall, precision, sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC) are used to evaluate our proposed method’s performance. The scaphoid bone detection achieved an accuracy of 99.70%. The results of scaphoid fracture detection with the rotational bounding box revealed a recall of 0.789, precision of 0.894, accuracy of 0.853, sensitivity of 0.789, specificity of 0.90, and AUC of 0.920. The resulting scaphoid fracture classification had the following performances: recall of 0.735, precision of 0.898, accuracy of 0.829, sensitivity of 0.735, specificity of 0.920, and AUC of 0.917. According to the experimental results, we found that the proposed method can provide effective references for measuring scaphoid fractures. It has a high potential to consider the solution of detection of scaphoid fractures. In the future, the integration of images of the anterior–posterior and lateral views of each participant to develop more powerful convolutional neural networks for fracture detection by X-ray radiograph is probably important to research.

[Effect of miR-186 targeting E-cadherin on proliferation and metastasis of renal cell carcinoma]

Objective: To investigate the role of miR-186 in renal cell carcinoma (RCC) and its molecular mechanism of miR-186 targeting E-cadherin to inhibit cell proliferation and metastasis of RCC. Methods: A total of 40 RCC samples which were collected in Shanxi Provincial People's Hospital from January 2015 to January 2019 and four RCC cell lines were measured the expression of miR-186 by real-time quantitative polymerase chain reaction (qPCR). The effect of miR-186 overexpression on the proliferation, invasion, migration and apoptosis of 786-O cells were detected by cell counting kit-8(CCK-8), colony formation, wound healing and Transwell assay and flow cytometric analysis. The effect of miR-186 on the expression of epithelial-to-mesenchymal transition (EMT) related markers (E-cadherin, N-cadherin and Vimentin) was analyzed by Western blot, and the dual luciferase reporter was used to verify the miR-186 targeting E-cadherin. Results: There were 26 males and 14 females with an age of (58.4±9.2) years. miR-186 expression levels decreased significantly in RCC tissues and cells (tissues: 0.005 2±0.000 4 vs 0.015 5±0.001 5, P<0.001; cells: 0.334 3±0.025 1, 0.457 0±0.026 6, 0.229 8±0.011 0, 0.741 1±0.091 0 vs 1.000 0±0.085 2, all P<0.001). The expression of miR-186 had a negative correlation with tumor size (≥4 cm: 0.003 2±0.003 4 vs<4 cm: 0.008 4±0.007 2, P<0.001), TNM staging (≤Ⅱ: 0.007 8±0.005 8 vs>Ⅱ: 0.002 7±0.002 3, P=0.021) and Fuhrman grade (<Ⅱ: 0.008 8±0.006 3 vs ≥Ⅱ: 0.004 6±0.003 0, P<0.001). The overexpression of miR-186 significantly inhibited cell proliferation and metastasis, and induced cell apoptosis. delivered.miR-186 overexpression can retard tumor growth in nude mice. Luciferase assay showed that E-cadherin was a direct target gene of miR-186. Conclusion: miR-186 may affect EMT of RCC and inhibit the proliferation and metastasis of RCC by directly regulating E-cadherin.

[Malfunction of autophagy in tibial growth plate chondrocytes causes increased apoptosis rate in chronic renal insufficiency rats]

Objective: To observe the effect of autophagy of tibial growth plate chondrocyte on apoptosis in chronic renal insufficiency (CRI) rats. Methods: Male 4-week-old SD rats were randomly divided into two groups: (1) Sham group: only the left ureter was exposed (n=10); (2) CRI group: the left ureter was ligated to cause CRI (n=10). The urine from all the rats was collected 6 weeks after the operation and the total protein content was measured. Then all the rats were sacrificed and the concentrations of creatinine and urea nitrogen in intracardiac blood were detected. The proximal tibia were fixed and decalcified to prepare histological sections, and the number of chondrocytes of column cells in the proliferative area of tibia growth plate was observed by saffron O staining. The expression rate of protein Light Chain-3, an autophagy marker of chondrocytes, was detected by immunofluorescence. The apoptosis rate of chondrocytes was detected by the method of TUNEL assay. The level of glycogenin-1, a glycogen formation marker of chondrocyte was detected by immunohistochemistry in chondrocytes. Results: The 24 h urine total protein was higher in CRI group [(163.5±11.3) mg vs (38.6±9.8) mg, t=25.620, P<0.001]. The levels of blood creatinine [(67.3±16.2) μmol/L vs (28.4±11.5) μmol/L, t=5.974, P<0.001] and urea nitrogen [(16.4±6.4) mmol/L vs (4.8±2.0) mmol/L, t=5.198, P<0.001] were higher in CRI group. The number of chondrocytes of column cells in the proliferating area of tibia growth plate was lower in CRI group (4.2±2.1 vs 9.1±3.8, t=3.109, P=0.006). The expression rate of LC-3 protein in chondrocytes of CRI group was lower [(27.2±12.6)% vs (51.4±18.2)%, t=3.457, P=0.003]. The level of glycogenin-1 of chondrocytes in CRI group increased significantly (6.1±2.5 vs 3.5±1.8, t=2.669, P=0.016). The apoptosis rate of chondrocytes in CRI group also increased [(17.2±4.8)% vs (5.1±3.4)%, t=6.505, P<0.001]. Conclusion: Malfunction of autophagy in tibial growth plate chondrocytes causes increased apoptosis rate in CRI rats, which might be caused by the failure of glycogen degradation in chondrocytes.

[Effect of primary cilia expression rate on Wnt/β signaling pathway in tibial growth plate chondrocytes from chronic renal insufficiency young rats]

Objective: To observe the effect of primary cilia expression rate on Wnt/β signaling pathway in tibial growth plate chondrocytes from chronic renal insufficiency (CRI) young rats. Methods: Male 2-week-old SD rats were randomly divided into two groups: (1) Sham group: only the left ureter was exposed (n=6); (2) CRI group: the left ureter was ligated (n=6). Rats were sacrificed 2 weeks after the operation and the primary cilia expression rate of growth plate chondrocytes and key protein β-catenin in Wnt/β signaling pathway were observed in histological section of tibia specimen. Chondrocytes isolated from growth plate in two groups were cultured in vitro to P3 generation. The primary cilia expression rate and the level of β-catenin were measured. The primary cilia expression rate was detected by agonists and antagonists Wnt/β signaling pathway in chondrocytes of CRI group. The level of β-catenin was detected by using serum-free culture and chloral hydrate to intervene chondrocytes in CRI group. Results: The primary cilia expression rate of growth plate chondrocytes in histological section of tibia specimen in CRI group was higher than that in Sham group [(17.5±7.7)% vs (8.7±3.6)%, t=3.237, P=0.005], and the level of β-catenin was higher in CRI group (5.1±0.7 vs 1.9±0.8, t=6.731, P<0.001). The primary cilia expression rate of growth plate chondrocytes cultured in vitro in CRI group was higher than that in Sham group [(20.9±8.1)% vs (11.8±4.7)%, t=3.073, P=0.007], and the level of β-catenin was higher in CRI group (0.49±0.12 vs 0.25±0.11, t=3.297, P=0.011). There was no significant change in primary cilia expression rate after intervention by using Wnt/β signaling agonists and antagonists to change the level of β-catenin [agonists group: (21.3±7.6)%, control: (20.6±6.8)%, antagonists group: (22.4±6.2)%, F=0.173, P=0.842]. The level of β-catenin was significantly changed after intervention by using serum-free culture, chloral hydrate to alter the primary cilia expression rate (serum-free culture group: 0.61±0.23, control: 0.39±0.24, chloral hydrate group: 0.15±0.11, F=6.476, P=0.012). There was a positive correlation between the level of β-catenin and primary cilia expression rate. Conclusion: The primary cilia expression rate and the level of Wnt/β signaling pathway were higher in tibial growth plate chondrocytes in CRI rats model, and primary cilia might have positive regulatory effects on the Wnt/β signaling pathway.

[Effect of primary cilia on growth plate chondrocyte proliferation of young rats with chronic renal insufficiency]

Objective: To observe the effect of primary cilia on growth plate chondrocyte proliferation of young rats with chronic renal insufficiency (CRI). Methods: Male 2-week-old Sprague-Dawley rats were randomly divided into two groups (with 10 in each group): Sham group (only left ureter was exposed) and CRI group (left ureter was ligated). Rats were sacrificed 2 weeks after operation and the total length of tibia was measured. Histological sections of tibia were taken to observe the chondrocytes of growth plate proliferative region and the expression rate of primary cilia. Chondrocytes from growth plate in two groups were isolated and cultured in vitro to P3 generation and the chondrocyte proliferation rate at 24 h were detected. The primary cilia expression rate and cilia length of chondrocytes were measured. Western blot was used to detect the expression of intraflagellar transport 88 (IFT88) protein and the gray scale was analyzed. Results: The total length of tibia was shorter in CRI group [(35.84±4.56) mm vs (42.33±3.44) mm, P=0.002]. The results of tibial histological section showed that chondrocytes of growth plate proliferative region were unorganized and the number of chondrocyte with columnar structure was less in CRI group (2.71±1.10 vs 7.68±1.32, P<0.001). The primary cilia expression rate of chondrocytes was higher in CRI group [(35.53±7.41)% vs (18.31±5.12)%, P<0.001]. The chondrocyte proliferation rate at 24 h was lower in CRI group [(11.38±6.10)% vs (24.35±8.46)%, P=0.001]. The primary cilia expression rate of chondrocytes was higher in CRI group [(60.12±7.86)% vs (32.17±8.97)%, P<0.001], and the primary cilia length of chondrocytes was longer in CRI group [(3.54±1.61) μm vs (1.96±0.82) μm, P=0.012]. The protein IFT88 was more highly expressed in CRI group (0.47±0.23 vs 0.17±0.10, P=0.001). Conclusion: The primary cilia expression rate of growth plate chondrocytes was higher in the rats with CRI, resulting in decreased chondrocyte proliferation rate and growth retardation of tibial growth plate.

[Mechanism of lung injury of rats induced by inhalation of white smoke from burning smoke pot]

Objective: To explore mechanism of lung injury of rats induced by inhalation of white smoke from burning smoke pot. Methods: Forty-eight Sprague Dawley rats were divided into control group (n=12) and injury group (n=36) according to the random number table. Rats in injury group were placed in smoke-induced injury experimental equipment fulled with white smoke from burning smoke pot for 5 minutes to make lung injury, and rats in control group were placed in smoke-induced injury experimental equipment fulled with air for 5 minutes to make sham injury. Six rats in injury group at post injury hour (PIH) 6, 24, and 72 and six rats in control group at PIH 72 were collected to observe pathological changes of lung tissue and pathological score of rats in the two groups by hematoxylin-eosin staining, to detect expression of nuclear factor-κB (NF-κB) p65 mRNA in lung tissue of rats by reverse transcriptional polymerase chain reaction, and to detect content of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 in lung tissue of rats by enzyme-linked immunosorbent assay. Data were processed with one-way analysis of variance and t test. Results: At PIH 72, lung tissue structure of rats in control group was clear and complete, with no inflammatory cell infiltration. At PIH 6, there was edema, hemorrhage, and inflammatory cell infiltration in lung tissue of rats in injury group. At PIH 24, edema, hemorrhage, and inflammatory cell infiltration in lung tissue of rats in injury group aggravated. At PIH 72, area of edema in lung tissue of rats in injury group was enlarged, with obvious hemorrhage and inflammatory cell infiltration. At PIH 6, 24, and 72, pathological score of lung tissue of rats in injury group was (3.43±0.86), (5.39±0.93), and (9.99±0.84) points, respectively, obviously higher than that of rats in control group at PIH 72 [(2.11±0.20) points, t=3.659, 8.450, 22.355, P<0.05]. As time post injury prolonged, pathological scores of lung tissue of rats in injury group were significantly increased (F=121.244, P<0.01). At PIH 6, 24, and 72, expression of NF-κB p65 mRNA in lung tissue of rats in injury group was 15.5±4.3, 25.9±1.8, 30.9±3.5 respectively, significantly higher than that of rats in control group at PIH 72 (7.8±0.8, t=4.315, 20.445, 14.408, P<0.01). As time post injury prolonged, expression of NF-κB p65 mRNA in lung tissue of rats in injury group gradually increased (F=32.691, P<0.01). At PIH 6, 24, and 72, content of TNF-α, IL-1β, and IL-6 in lung tissue of rats in injury group was significantly higher than that of rats in control group at PIH 72, respectively (t=7.650, 8.968, 6.827, 6.726, 8.978, 3.460, 5.420, 13.289, 16.438, P<0.01). At PIH 24, content of TNF-α and IL-1β in lung tissue of rats in injury group was higher than that of rats in the same group at PIH 6 and 72, respectively (t=3.409, -2.549, 4.047, -4.100, P<0.05). At PIH 24 and 72, content of IL-6 in lung tissue of rats in injury group was respectively higher than that of rats in the same group at PIH 6 (t=8.273, 9.711, P<0.05). Conclusions: After inhaling white smoke from burning smoke pot, rats are inflicted with lung injury by increasing expression of NF-κB p65 mRNA and content of TNF-α, IL-1β, and IL-6, and induce pathological changes of edema, hemorrhage, and inflammatory cell infiltration of lung tissue.

DNA hydroxymethylation rate in the AChE and HoxC4 promoter associated with human sperm quality

The relationship of altered DNA 5'-hydroxymethylation in human spermatozoa with seminal parameters remains unclear. The aim of the study was to investigate the association between the 5'-hydroxymethylcytosine (5hmC) rate in the promoters of acetylcholinesterase (AChE) and homeobox C4 (HoxC4) genes and human sperm concentration/motility. The study population consisted of three groups: asthenozoospermia (AZ), oligoasthenozoospermia (OAZ) and normozoospermia (NZ). The 5hmC rate in the promoter was measured by CCGG loci-dependent MspI/HpaII restriction mapping of glycosylation-modified sperm DNA combined with a hydroxymethylation-specific real-time polymerase chain reaction assay. The 5hmC rate in the AChE promoter in group AZ and OAZ was higher than that in group NZ (p < .05). A weak inverse correlation between 5hmC rate of AChE and sperm motility was observed in all subjects (r = -.172, p < .05). The 5hmC rate in the HoxC4 promoter in group OAZ was lower than that in group NZ (p < .05). These results indicated that altered 5hmC rates of AChE and HoxC4 promoters are associated with low sperm motility and sperm concentration respectively.

[The vessel and primary glaucoma]

Glaucoma, as the first leading cause of irreversible blindness in the world, is a chronic progressive optic neuropathy. The pathogenesis of glaucoma is still not fully understood till now. A lot of studies about vascular diameter, tortuosity, location, disc perfusion, vascular regulation and systemic vascular factors had been conducted to investigate the relationship between the vascular states and glaucoma since vascular hypothesis proposed. However, direct and convincing evidence for primary mechanisms of glaucoma is still lacking. The development of OCT, especially the Angio-OCT makes the real time visualization and measurement of ocular perfusion in vivo possible, gives some new evidences of vascular dysfunction of optic nerve head associated with glaucoma, which enhancing thinking of the pathogenesis of glaucoma. This review summarizes the literatures on vascular factors associated with glaucoma to provide the references for clinical researches. (Chin J Ophthalmol, 2017, 53:791-796).

Cytotoxic Edema in Posterior Reversible Encephalopathy Syndrome: Correlation of MRI Features with Serum Albumin Levels

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome is a clinicoradiologic entity with typical MR imaging showing predominant vasogenic and occasional cytotoxic edema. It is unclear whether MR imaging correlates with levels of serum albumin. We determined potential risk factors for development of cytotoxic edema in posterior reversible encephalopathy syndrome.

MATERIALS AND METHODS

Seventy-nine cases with typical clinical symptoms and characteristic neuroradiologic findings conformed to posterior reversible encephalopathy syndrome diagnostic criteria and were included in this study. FLAIR, DWI, and ADC maps were interpreted to evaluate the severity and type of edema. MR imaging was correlated with the levels of serum albumin, and cytotoxic edema was compared with the location and severity of brain edema.

RESULTS

Pure vasogenic edema was found in 53 cases (67.09%), and vasogenic edema complicated with cytotoxic components, in 26 patients (32.91%). There was no difference in serum albumin levels between patients with cytotoxic components and those with vasogenic edema (P = .983). There was a significant difference in the edema scale scores between patients with cytotoxic edema and those with vasogenic edema (P = .006). The percentage of cytotoxic edema located in the area with higher scale scores of edema was significantly larger than that in areas with lower scale scores of edema (P = .002).

CONCLUSIONS

Serum albumin may contribute to the development of edema in PRES but is not a decisive factor for edema type. Cytotoxic edema in posterior reversible encephalopathy syndrome is probably related to regional decreased perfusion and arteriolopathy. Further work should be undertaken to discover the pathophysiologic mechanisms involved.

Sonocatalytic degradation of RhB over LuFeO3 particles under ultrasonic irradiation

LuFeO3 particles with an average particle size of ∼200 nm were synthesized via a polyacrylamide gel route. The sonocatalytic activity of LuFeO3 particles was evaluated by the degradation of Rhodamine B (RhB) under ultrasonic irradiation, revealing that they exhibit a good sonocatalytic activity. The effects of various experimental factors including ultrasonic frequency (f), reaction solution temperature (T), catalyst dosage (Ccatalyst), initial RhB concentration (CRhB), and pH value on the sonocatalysis efficiency were investigated. It is found that the former four factors have an important influence on the sonocatalytic degradation of RhB, where the best degradation conditions are obtained to be f=60 kHz, T=40 °C, Ccatalyst=4 g L(-1), and CRhB=5 mg L(-1). The pH value has a relatively small effect on the sonocatalytic degradation of RhB compared with other experimental factors. Hydroxyl (·OH) radicals were detected by fluorimetry using terephthalic acid as a probe molecule, revealing that they are produced over the ultrasonic-irradiated LuFeO3 particles. The addition of ethanol leads to a quenching of ·OH radicals and a simultaneous decrease in the RhB degradation. This indicates that ·OH radicals are the primary active species responsible for the dye degradation.

Establishment of reference panel for human platelet antigen genotyping

BACKGROUND AND OBJECTIVES

Human platelet antigens (HPAs) are platelet-specific alloantigens associated with polymorphisms of platelet surface glycoproteins (GPs), and they can induce alloantibodies when individuals lacking a particular polymorphism are exposed to them via pregnancy or transfusion. Immune responses to HPAs are involved in the pathogenesis of several clinical syndromes. HPA genotyping is therefore important for clinical diagnosis and laboratory research. This study aims to establish a reference panel for HPA genotyping.

MATERIALS AND METHODS

Genomic DNA extracted from human blood was used as the template for amplifying HPA (1a-5a and 15a) gene fragments using specific primers. The amplified products were cloned into pGM-T vectors, which were transformed into competent TOP10 cells. After clone screening and amplification, the plasmids were extracted and sequenced. Next, the gene fragments HPA-1b-5b and 15b were obtained by site-directed mutagenesis using the corresponding HPA-1a-5a and 15a plasmids as template DNA.

RESULTS

We successfully constructed reference plasmids for HPA genotyping with HPA-1a-5a, 15a, HPA-1b-5b and 15b. The DNA sequences were consistent with those published in GenBank.

CONCLUSION

Obtaining reference DNA for low-frequency HPAs is very difficult, and the successful construction of reference plasmids for the six HPA systems may solve this problem. Establishment of this panel has laid the foundation for future research on HPA genotyping.

A novel mechanism of NALP3 inducing ischemia reperfusion injury by activating MAPK pathway in acute renal failure

Acute renal failure (ARF) is a rapid loss of kidney function. The reasons and mechanism by which this occurs has not been clarified so far thus creating obstacles to management of this disease. Presently, the experimental research using the accepted renal ischemia reperfusion injury (I/R injury) model represented for ARF focuses on several possible relevant factors such as reactive oxygen species, no-reflow phenomenon, apoptosis and extensive inflammatory response. The latter is much talked about currently. Some intracellular danger sensing proteins, such as the nucleotide binding domain leucine rich repeats-containing family proteins known as NLRs, adjust the inflammatory response through the formation of a multi-protein complex known as an inflammasome. The most classic family member of this complex is NALP3 confirmed to serve as a contributor to I/R injury. However, how it contributes to the pathology remains obscure. The extensive inflammatory response is considered to be modulated by the mitogen-activated protein kinases (MAPK) signaling pathway. NOD2, another family member of NLR, which shares similar structure with NALP3, indicated that it induced the activation of MAPK in response to a pathogen, thus we assumed that NALP3 performed the harmful process of I/R injury, resulting probably from the activation of the MAPK signaling pathway. If this hypothesis proves to be correct, it might benefit the management of ARF.

Diagnosis and current management of gastrojejunocolic fistula

Gastrojejunocolic fistula is a late complication of gastroenterostomy and is associated with inadequate gastric resection and incomplete vagotomy. In the past, attempted primary repair had high mortality and staged operations were normally performed. We present two cases of gastrojejunocolic fistula and discuss the modern management of this condition. In both cases, improved nutritional support allowed successful one-stage surgical repair to be performed.

Plan-view imaging of oxygen-induced reconstruction on Ag(110) surface. I. The possibility of imaging surface oxygen

Surface reconstruction on Ag(110) induced by oxygen adsorption was studied by the plan-view imaging technique of high-resolution electron microscopy (HREM). Systematic multislice simulations were carried out to find the optimal experimental conditions for imaging the surface oxygen. It was found theoretically that there exist a series of characteristic values of objective lens defoci and sample thicknesses under which the surface and the bulk can be imaged clearly and simultaneously. These optimal imaging conditions were used to interpret the experimental micrographs. While the basic features of the surface reconstruction of O/Ag(110) in the HREM images are consistent with those revealed by scanning tunnelling microscopy (STM), there are some new features that have not been reported with STM. These phenomena give some evidence to the existence of subsurface oxygen.

Ornithine decarboxylase is a transcriptional target of tumor suppressor WT1

The product of the Wilm's tumor suppressor gene, WT1, is a zinc-finger DNA-binding protein, which is thought to be a transcription factor. Two genes, those encoding epidermal growth factor receptor and syndecan-1, are known to be endogenous targets of WT1. Previous studies had identified binding sites for WT1 in the promoter of the ornithine decarboxylase (ODC) gene. In this paper, we tested whether the endogenous ODC gene might be a target of WT1 by establishing lines of baby hamster kidney (BHK) cells that expressed WT1 isoform A under control of a tetracycline-regulated expression system. When expression of WT1 was activated in BHK cells, the cellular level of ODC mRNA declined, with kinetics that correlated with the increase in WT1 level, demonstrating that the endogenous ODC gene was indeed responsive to cellular level of WT1. WT1 isoforms A and B inhibited the activity of the ODC promoter by approximately fivefold in transiently transfected BHK cells, while isoforms C and D, which have altered DNA binding domains, had no significant effect. The sequence CTCCCCCGC, located at nucleotides -106 to -98 relative to the site of transcriptional initiation in the ODC gene, interacted with the zinc-finger domain of isoforms A and B of WT1 with high affinity and specificity. A mutation in the binding site that disrupted this interaction partially removed the inhibition of ODC promoter activity by WT1, as did mutation of the two E-box sequences in intron I of the ODC gene. Simultaneous mutation of the WT1-binding motif and the two E-boxes completely abolished inhibition by WT1 of ODC promoter activity. These results, taken together, implicate the ODC gene as a downstream target of the tumor suppressor WT1.

[Clinical study of effect of zhengda zhenhua 851-R oral liquor on delayed aging process]

A study was conducted on the effects of Zhengda Zhenhua 851-R (ZZ-851-R) oral liquor on middle aged-old patients with Kidney and Spleen Deficiencies. It was found that ZZ-851-R was able to relieve the symptoms of aging, improve the memory and fluency of speech, the activity of superoxide dismutase (SOD) GSH and GSH-peroxidase (GSH-Px) increased remarkably and serum lipid peroxide (LPO) level decreased significantly. Improvements of immunity, function of the pituitary-gonad axis were also noticed in the study, with decreased E2/T ratio and improved ability of total antioxydation. In summary, the ZZ-851-R has the effect of antisenility, without obvious side-effect.

[Effects of zhengda zhenhua 851 on improvement of memory and fluency of language of kidney deficiency patients]

A study was conducted on the effects of Zhengda Zhenhua 851-R oral liquor on the improvement of memory and fluency of language of patients suffering from Kidney Deficiency and control group. It was found that the treated group did better in memory tests and the index of mental quotient (MQ) was higher than that of control group. They had markedly higher scores in the tests of directional memory which requires one's initiative and the free recollection of pictures. The scores achieved by the treated group were significantly higher than that of control on the tests of the fluency of language and expressions, particularly with words of different categories. The results showed that Zhengda Zhenhua 851-R oral liquor obviously had the function of improving the memory and fluency of language for Kidney Deficiency patients.

Influence of 3,4',5-trihydroxystibene-3-beta-mono-D-glucoside on vascular endothelial epoprostenol and platelet aggregation

AIM

To study the relationship between the inhibiting effect on platelet aggregation and the enhancing effect on epoprostenol (PGI2) released from vascular endothelium with 3,4',5-trihydroxystibene-3-beta-mono-D-glucoside (polydatin, Pol).

METHODS

After having been incubated with Pol, the incubating medium was withdrawn from the bottles with newborn umbilical vein endothelial cells (VEC group, trypsin digesting method) and added to the platelets (washing method). The medium withdrawn from the bottles without VEC was designated as control group. Reduction of platelet aggregation rates (PAR, turbidity method) and changes of 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane B2 (TXB2) (radioimmunoassay method) in the supernatant of the aggregated platelets induced by thrombin were scrutinized.

RESULTS

PAR in the control group showed no reduction, whereas PAR reduction (-10 +/- 10) and 6-keto-PGF1 alpha increase (108 +/- 30 ng.L(-1)) in the VEC group treated 10 min with Pol 0.41 mmol.L(-1) (vs that of distilled water, ie, 2 +/- 12 and 54 +/- 20 ng.L(-1)) occurred.

CONCLUSION

Increase of PGI2 from VEC by Pol was involved in its (Pol's) inhibition effect of platelet aggregation.

Complex interactions at a GC-rich domain regulate cell type-dependent activity of the ornithine decarboxylase promoter

Regulation of ornithine decarboxylase (ODC) is critical to the control of cellular growth, differentiation, and carcinogenesis. A GC-rich region in the ODC promoter contains two overlapping protein binding sites that interact to regulate basal level expression in some cell types. A perfect binding motif for transcription factor Sp1 (CCCCGCCCC) is located at nucleotides -114 to -106 relative to the site of transcriptional initiation, binds strongly to purified Sp1 protein, and forms several complexes when incubated with nuclear extracts. Only one of these complexes is recognized by Sp1-specific antibody. A new protein-binding motif (GCCCCTCCCC, located at -110 to -100) partially overlaps with the Sp1 site and analyses by DNase I protection showed that a new protein ("NF-ODC1") and the Sp1-like proteins interact with the ODC promoter in a mutually exclusive manner. Mutation of the NF-ODC1 binding motif strongly enhanced ODC promoter strength in some cell types, but had little or no influence in others. The effect of mutating the Sp1 site also varied with cell type. These cell type specificities did not correlate with the levels of Sp1 and NF-ODC1 binding activities in nuclear extracts. These results show that regulation of the ODC promoter by the Sp1 family is cell type-specific and modulated by a negative effector that we have termed NF-ODC1.

The sartorius myocutaneous island flap

The vascular supply to the distal part of sartorius m. was studied in 37 limbs by dissection under magnification and after black ink and latex injections. The muscle or myocutaneous island flap pedicled on the saphenous artery (SA) is supplied by a retrograde circulation through anastomoses of the SA with the perforating branches of the posterior tibial artery and the medial inferior genicular artery. Three different vascular patterns were defined. Retrograde injection also showed good perfusion of the SA. The flap is useful for covering around the knee, the proximal and middle thirds of the lower leg, and the end of the amputation stump. Raising of the flap has not resulted in any functional or cosmetic defect. Eighteen operations have so far been performed, six using the muscle island flap and twelve using the myocutaneous island flap, and all survived completely.

[The effect of low doses of recombinant human erythropoietin on renal anemia in predialysis patients with chronic renal failure]

Subcutaneous (s.c.) administration of recombinant human erythropoietin (rHuEPO) has been proven to be effective in anemia of predialysis patients with chronic renal failure (CRF). However, the optimal dosage and frequency of administration have not been established. We use low dose (< 100U.kg-1.w-1) of s.c. rHuEPO to treat renal anemia in two groups (group A: n = 18, twice a week; group B; n = 14, once a week) of nondialytic CRF patients. Hb and Hct gradually increased 1-3 months aftes rHuEPO treatment in the two groups. The incidence of hypertension, one of the main side effects, was lower (4/18 in Group A, 4/14 in Group B) than that reported in the literature. These results showed that either twice weekly or once weekly s.c. injection of low dose rHuEPO is effective and there will be less side effects treating predialysis patients with CRF.

Characterization of amelogenin mRNA from secretory- and maturation-stage rat incisor enamel

Amelogenins are extracellular matrix proteins expressed at the secretory and the maturation stages of enamel formation. To characterize amelogenin transcripts from these two stages, rat incisor enamel-organ mRNA was hybridized to a mouse amelogenin cDNA. Northern analysis of the mRNA showed four amelogenin transcripts at the secretory stage. Two of these were larger than previously described, and would code for high molecular-weight amelogenins (> 40 kDa). These transcripts were similar in size to at least three bovine amelogenin mRNAs. At the maturation stage, one transcript slightly smaller than the major amelogenin transcript from the secretory stage was apparent. These differences may indicate a selective splicing of amelogenin mRNA in the maturation stage as compared to the secretory stage of enamel development.

Multiple DNA elements responsible for transcriptional regulation of the ornithine decarboxylase gene by protein kinase A

Transcription of the ornithine decarboxylase (ODC) gene is rapidly elevated by activation of protein kinase A (PKA). The additive influence of three cis-acting elements is responsible for this regulation in an adrenal carcinoma cell line. Two sites, CRE2 at -48 base pairs (bp) relative to the start of transcription and CRE3 at +95 bp, are identical to the core motif of the cAMP-responsive element (CRE) of the somatostatin gene and are conserved in the mouse, rat, and human ODC genes. Mutation of CRE2 resulted in a substantial decrease in basal promoter activity, as well as a 5-fold decrease in inducibility of the ODC promoter by PKA. CRE3 did not contribute to the basal activity of the ODC promoter, but mutation of this site resulted in a 2-fold decrease in inducibility by PKA. Deletion of a 45-bp sequence (GC-box) located 5' of CRE2, also resulted in a 2-fold decrease in inducibility of the ODC promoter. DNase I protection revealed the presence of protein binding at CRE2, the TATA box, and the GC-box of the ODC promoter. Mutation of CRE2 resulted in loss of protection of this sequence, as well as the 3' extension of the footprint over the TATA box, without affecting interactions at the GC box. Antibodies to the well characterized CRE-binding protein CREB recognized proteins binding to CRE2, suggesting that binding of CREB, or an antigenically related protein, is important for the activity of CRE2. Additionally, recombinant CREB bound to a DNA probe containing the CRE2 sequence.

Two polyhydroxylated steroids from the Chinese soft coral Sinularia microclavata

Two polyhydroxylated steroids have been isolated from the South China Sea soft coral Sinularia microclavata, and their structures were established as 24-methylenecholestane-1 alpha,3 beta,5 alpha,6 beta-tetrol and 1 alpha,3 beta,5 alpha-trihydroxy-24-methylenecholestan-6-one from spectral evidence and from comparison with two reference compounds, numersterol A and 24-methylenecholestane-1 alpha,3 beta,5 alpha,6 beta, 25-pentol, which were isolated from the soft corals, Simularia numerosa and Sarcophyton glaucum, respectively.

Mechanism of the reaction catalyzed by mandelate racemase. 2. Crystal structure of mandelate racemase at 2.5-A resolution: identification of the active site and possible catalytic residues

The crystal structure of mandelate racemase (MR) has been solved at 3.0-A resolution by multiple isomorphous replacement and subsequently refined against X-ray diffraction data to 2.5-A resolution by use of both molecular dynamics refinement (XPLOR) and restrained least-squares refinement (PROLSQ). The current crystallographic R-factor for this structure is 18.3%. MR is composed of two major structural domains and a third, smaller, C-terminal domain. The N-terminal domain has an alpha + beta topology consisting of a three-stranded antiparallel beta-sheet followed by an antiparallel four alpha-helix bundle. The central domain is a singly wound parallel alpha/beta-barrel composed of eight central strands of beta-sheet and seven alpha-helices. The C-terminal domain consists of an irregular L-shaped loop with several short sections of antiparallel beta-sheet and two short alpha-helices. This C-terminal domain partially covers the junction between the major domains and occupies a region of the central domain that is filled by an eight alpha-helix in all other known parallel alpha/beta-barrels except for the barrel domain in muconate lactonizing enzyme (MLE) [Goldman, A., Ollis, D. L., & Steitz, T. A. (1987) J. Mol. Biol. 194, 143] whose overall polypeptide fold and amino acid sequence are strikingly similar to those of MR [Neidhart, D. J., Kenyon, G. L., Gerlt, J. A., & Petsko, G. A. (1990) Nature 347, 692]. In addition, the crystal structure reveals that, like MLE, MR is tightly packed as an octamer of identical subunits. The active site of MR is located between the two major domains, at the C-terminal ends of the beta-strands in the alpha/beta-barrel domain. The catalytically essential divalent metal ion is ligated by three side-chain carboxyl groups contributed by residues of the central beta-sheet. A model of a productive substrate complex of MR has been constructed on the basis of difference Fourier analysis at 3.5-A resolution of a complex between MR and (R,S)-p-iodomandelate, permitting identification of residues that may participate in substrate binding and catalysis. The ionizable groups of both Lys 166 and His 297 are positioned to interact with the chiral center of substrate, suggesting that both of these residues may function as acid/base catalysts.(ABSTRACT TRUNCATED AT 400 WORDS)

Activation of p34cdc2 kinase by cyclin A

Functional clam cyclin A and B proteins have been produced using a baculovirus expression system. Both cyclin A and B can induce meiosis I and meiosis II in Xenopus in the absence of protein synthesis. Half-maximal induction occurs at 50 nM for cyclin A and 250 nM for cyclin B. Addition of 25 nM cyclin A to activated Xenopus egg extracts arrested in the cell cycle by treatment with RNase or emetine activates cdc2 kinase to the normal metaphase level and stimulates one oscillatory cell cycle. High levels of cyclin A cause marked hyperactivation of cdc2 kinase and a stable arrest at the metaphase point in the cell cycle. Kinetic studies demonstrate the concentration of cyclin A added does not affect the 10 min lag period required for kinase activation or the timing of maximal activity, but does control the rate of deactivation of cdc2 kinase during exit from mitosis. In addition, exogenous clam cyclin A inhibits the degradation of both A- and B-type endogenous Xenopus cyclins. These results define a system for investigating the biochemistry and regulation of cdc2 kinase activation by cyclin A.

[Increased ornithine decarboxylase activity is not essential for progesterone-induced Bufo oocyte maturation]

Ornithine decarboxylase (ODC) activity increases by 2 times in the process of progesterone-induced Bufo oocyte maturation (Table 1). Tumor promotor phorbol ester (PMA) is unable to affect both basal and stimulated ODC activity (Fig. 5) although it is capable of elevating the rate of steroid-induced maturation (Fig. 4). Spermine can inhibit significantly ODC activity of oocytes (Fig. 3). Hormone-stimulated ODC activity falls by 17% when Bufo oocytes are cultured in the alkaline Ringer's solution containing 5 mM spermine (pH 11.6) (Fig. 2). The period, however, is shortened by more than 50% during which the oocytes undergo GVBD (Fig. 1). Otherwise, spermine is found to repress ODC activity in dose dependent manner when microinjected in Bufo oocytes (Fig. 3). But oocytes undergo GVBD with a frequency of more than 80% when progesterone-induced increment of the enzyme activity is totally inhibited in the oocytes injected with approximately 50 nl 4.0 mM spermine. The conclusion may emerge from the above-stated results that increased ornithine decarboxylase activity is not essential for progesterone-induced Bufo oocyte maturation. In addition, ODC activity begins to increase rapidly when endogenous spermine level has been lowered to the largest extent in the maturation process. Therefore the endogenous spermine probably acts as a physiologically negative regulator of ODC activity since exogenous spermine inhibits seriously ODC activity of Bufo oocytes.

Influence of latent iron deficiency on generation of oxygen species in polymorphonuclear leucocytes

Measurement of luminol-dependent chemiluminescence (CL) was employed to estimate the generation of reactive oxygen species (ROS) in polymorphonuclear leukocytes (PMN) in patients with latent iron deficiency. There were no differences in the resting value of PMN CL among 20 patients with iron deficient erythropoiesis (2.92 + 0.38 number of pulses) and 20 normal controls (3.07 + 0.52; P greater than 0.05), but a significant decrease of peak value of PMN CL was observed in patients (45.82 + 7.41) as compared with controls (76.08 + 10.12; P less than 0.01). CL production by PMN in 6 patients with storage iron depletion was similar to that of 6 healthy controls. As a good correlation was found between the peak value of PMN CL and free erythrocyte protoporphyrin (FEP) level, increase of FEP could serve as a clinical indicator in the evaluation of decrease of ROS generation in PMN of patients with iron deficiency. Oral iron supplementation could effectively improve the impaired PMN ROS generation.

Characteristics of a cell line established from a Chinese patient with a squamous carcinoma of the uterine cervix

A new cell line, CC3/CUHK3, was established from a squamous carcinoma of the uterine cervix from a Chinese patient. Light microscopy of the cell line revealed keratin and electron microscopy demonstrated tonofilaments and desmosomes, thereby confirming its epithelial nature. The population doubling time of CC3/CUHK3, estimated from the exponential growth phase of the growth curve established from the cell line was 42 hours. When the tumour cells were inoculated into athymic mouse, a tumour, microscopically diagnosed as a well-differentiated carcinoma, developed. These cells are highly invasive in vitro.

[Various transformations of polycythemia vera]

90 cases of polycythemia vera (PV) were diagnosed and followed up more than 3 years in PUMC Hospital from 1957 to 1986. 15 cases (16.7%) had various transformations during their courses. 4 cases had more than one kind of transformation. As a rare event, one case transformed to chronic lymphocytic leukemia. For illustration, some typical cases were presented, and the related fetuses discussed.

[Proteins and proteinase-resistant polypeptides of delta-endotoxins from Bacillus thuringiensis and their insecticidal activity]

Proteins, solubility in alkaline buffer and proteinase-resistant polypeptides (PRP) of parasporal crystals (delta-endotoxin) from Bacillus thuringiensis were investigated. 19 sorts of crystals were divided into 7 types. Difference of crystalline proteins were coincident with their solubility and PRP. The characters of the protein, solubility and PRP were subspecies-specific basically, but in a few of crystals they were strain-specific. There was a closed relation between the biochemistry property of crystal protein and the toxicity in 2 species of insects. Crystal with protein of MW 130-138 kD kD or MW 130-138 kD and 60-65 kD, and PRP of MW 68-75 kD were high toxic in Bombyx mori (Lepidoptera), but most of them only showed weak or no toxicity in Culex fatigans (Diptera). Crystals containing more than 3 sorts of proteins with MW 15-138 kD in major protein and MW 35-75 kD in minor protein and PRP of 35-65 kD had very strong toxicity in Culex fatigans, but no toxicity in Bombyx mori. The construct of the crystal protein and the importance of the character in protein and PRP for the selection of expected strain and for the work of genetic engineering in Bacillus thuringiensis were discussed.