[Preliminary measurement and analysis of the condylar movement envelope surface parameters in healthy adults]

Objective: To measure and analyze parameters of the three-dimensional (3D) model of the condylar movement envelope surface (ES) and provide a reference for the design of the temporomandibular prosthesis. Methods: Thirty-four healthy adults aged (25.4±2.8) years were recruited from the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology as subjects. There were 9 males and 25 females, most of them were university students and others outside the university have received undergraduate education or above. Condylar movement ES were obtained using the previous method on the 3D trajectory of condyle. The simulations of condylar movement were projected according to opening movements, protrusion movements, and lateral movements respectively. The total area of the ES and the area proportions of models formed by above different mandibular movements were measured and calculated. The adults' head and maxillofacial 3D models reconstructed by cone beam CT were registered with ES in Geomagic Studio. The inner and outer poles of the condyle, the corrective sagittal axis of the ES, and the median sagittal plane (MSP) were calibrated in registration models using Geomagic Studio, and the parameters were measured as follows: the anteroposterior and medialateral diameters of the condyle, the anteroposterior diameters and the transverse diameters (anterior, middle and posterior parts) of the ES, the angles between the corrective sagittal axis of the ES and MSP (ES-MSP). Pearson correlation analysis was performed by SPSS 24.0. Results: The total area of the ES was (760±133) mm², the opening movement part accounted for (63.3±15.2)%, the protrusion movement part accounted for (14.9±9.6)%, the lateral movement part accounted for (21.8±13.3)%. Parameter measurements were as follows: mediolateral diameters of condyle was (19.8±2.3) mm; anteroposterior diameter of the ES was (21.2±3.1) mm, the transverse diameters (anterior, middle and posterior parts) of the ES were (20.6±2.4), (20.4±2.4), (22.0±2.6) mm, respectively; the transverse diameters of the ES were about 2 mm larger than that of the condyle. The angle between the corrective sagittal axis of ES and the MSP was 6.8°±6.2°. The coefficient of variation (CV) in these parameters showed: CV of the transverse diameters (anterior, middle and posterior parts) of the ES and mediolateral diameter of the condyle were 0.98, 0.99, 0.93, respectively (P<0.001). CV of aera of ES and mediolateral diameter of the condyle was 0.64 (P=0.002). CV of aera of ES and anteroposterior diameter of ES was 0.62 (P=0.004). Conclusions: The 3D envelope surface model formed by mandibular opening movements accounted for the largest proportion of the ES. The corrective sagittal axis of the ES was at an angle to the MSP, the transverse diameters (anterior, middle and posterior parts) of the ES were approximately 2 mm larger than the mediolateral diameter of the condyle, the transverse diameters (anterior, middle and posterior parts) of the ES were highly positively correlated with the mediolateral diameter of the condyle.

Antimicrobial peptide MPX attenuates LPS-induced inflammatory response and blood-testis barrier dysfunction in Sertoli cells

Orchitis accounts for a high proportion of male animal reproductive disorders. Hence, it is urgent to identify drugs for the prevention and treatment of orchitis. Antimicrobial peptides (AMPs) are currently recognized as one of the most promising alternatives to antibiotics. However, the protective effects of AMPs on lipopolysaccharide (LPS)-induced orchitis have not been reported. In this study, we developed an LPS-induced orchitis model in which primary bovine Sertoli cells were used as model cells. MPX was indicated to effectively reduce the inflammatory response of Sertoli cells. MPX attenuated the gene expression of the proinflammatory cytokines TNF-α, IL-6 and IL-1β by suppressing the MAPK pathway, especially the phosphorylation of p38 and ERK. MPX also decreased the oxidative stress response caused by LPS and upregulated Occludin and Claudin-1 expression, thereby maintaining the integrity of the blood-testis barrier. Moreover, we found that MPX inhibited apoptosis in Sertoli cells. In a mouse model, we found that MPX significantly inhibited the disruptive effects of LPS, reducing seminiferous epithelium damage, vacuolations, hyperplasia, and apoptosis in spermatogenic cells and rescuing spermatogenesis. In addition, the expression of inflammatory factors such as IL-1β, IL-18, IL-6 and TNF-α was decreased after MPX treatment in the mouse testes. MPX had no effect on other organs in mice, indicating its safety. This study was undertaken to investigate how MPX regulates the inflammatory response in Sertoli cells and provide a reference for the clinical prevention and treatment of male animal orchitis.

[The expression of clock gene CLOCK and its clinical significance in nasopharyngeal carcinoma]

Objective: To explore the relationship between expression levels of CLOCK mRNA and protein and the clinical characteristics of patients with nasopharyngeal carcinoma. Methods: The frozen tissue specimens from 33 patients with nasopharyngeal carcinoma in the Affiliated Tumor Hospital of Guizhou Medical University from 2018 to 2019 were collected. Seventeen cases of tissue specimens from patients with nasopharyngeal chronic inflammation in the Affiliated Hospital of Guizhou Medical University in 2019 were collected. From 2008 to 2014, 68 cases of formalin-fixed paraffin-embedding (FFPE) nasopharyngeal carcinoma tissue and 37 cases of FFPE nasopharyngeal chronic inflammation tissue were collected from the Affiliated Tumor Hospital of Guizhou Medical University. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) were used to detect the mRNA and protein expression levels of CLOCK. The nasopharyngeal carcinoma cells including CNE1, CNE2, 5-8F and the normal nasopharyngeal epithelial cell NP69 were cultured. qRT-PCR was used to detect the expression level of CLOCK mRNA in each cell line at the time points of ZT2, ZT6, ZT10, ZT14, ZT18 and ZT22. The cosine method was used to fit the rhythm of CLOCK gene in nasopharyngeal carcinoma. The protein expression of CLOCK protein was detected by using immunohistochemical method in 68 cases of nasopharyngeal carcinoma and 37 cases of nasopharyngeal chronic inflammation tissue. Survival was analyzed by Kaplan-Meier method and Log rank test, and the influencing factors was analyzed by Cox regression model. Results: The expression levels of CLOCK mRNA in CNE1, CNE2 and 5-8F cells (0.63±0.07, 0.91±0.02 and 0.33±0.04, respectively) were lower than that in NP69 cell (1.00±0.00, P<0.05). The expression levels of CLOCK protein in CNE1, CNE2 and 5-8F cells (0.79±0.06, 0.57±0.05 and 0.74±0.10, respectively) were lower than that of NP69 cells (1.00±0.00, P<0.05). The expressions of CLOCK mRNA in nasopharyngeal carcinoma cells including CEN1, CNE2, 5-8F and normal nasopharyngeal epithelial cell NP69 were different at different time points, with temporal fluctuations. The fluctuation periods of CLOCK mRNA in CNE1, CNE2, 5-8F, and NP69 cells were 16, 14, 22 and 24 hours, respectively. The peak and trough times were ZT10: 40 and ZT18: 40, ZT10 and ZT3, ZT14: 30 and ZT3: 30, ZT12: 39 and ZT0: 39, respectively. CLOCK mRNA and protein expression levels in nasopharyngeal carcinoma tissues (0.37±0.20 and 0.20±0.26, respectively) were lower than those in nasopharyngeal chronic inflammation tissues (1.00±0.00 and 0.51±0.41, respectively, P<0.05). The 1, 3, and 5-year survival rates of patients in the CLOCK protein high expression group (CLOCK protein expression level ≥ 0.178) were 96.2%, 92.1%, and 80.1%, respectively, which were higher than those in the low expression group (CLOCK protein expression level <0.178, 92.9% , 78.6% and 57.1%, respectively, P=0.009). The 1, 3, and 5-year progression-free survival (PFS) rates of patients in the CLOCK protein high expression group were 96.2%, 87.8%, and 87.7%, respectively, which were higher than those in the low expression group (92.7%, 82.2%, and 70.8%, respectively, P=0.105). Compared with the low-expression group (100.0%, 96.9%, and 90.0%, respectively), the 1, 3, and 5-year recurrence-free survival rates of patients in the CLOCK protein high expression group (100.0%, 95.7%, and 95.7%, respectively) were not statistically significant (P=0.514). Compared with the low-expression group (92.7%, 82.2%, and 79.3%), the 1, 3, and 5-year survival rates without metastasis in the CLOCK protein high expression group (96.2%, 92.0%, and 92.0%, respectively) were not statistically significant (P=0.136). CLOCK protein expression and T stage were independent prognostic factors of overall survival (P<0.05). Conclusions: The expression of CLCOK is downregulated in the nasopharyngeal carcinoma cell and nasopharyngeal carcinoma tissues. Clock gene CLOCK is rhythmically expressed in the nasopharyngeal carcinoma cells and normal nasopharyngeal epithelial cells. Compared with normal nasopharyngeal epithelial cells, the fluctuation period of CLOCK in nasopharyngeal carcinoma cells is shortened. The overall survival of patients in the CLOCK protein high expression group is better than that of low expression group. The expression of CLOCK protein is an independent influencing factor for overall survival. CLOCK gene may be a potential tumor suppressor gene in the nasopharyngeal carcinoma.

Application of Convolutional Neural Network in Identifying Different Levels of Isokinetic Exercise Efforts

Objective To develop a convolutional neural network （CNN） that can identify isokinetic knee exercises moment of force-time diagrams under different levels of efforts. Methods The 200 healthy young volunteers performed concentric isokinetic right knee flexion-extension reciprocating exercises with maximal effort as well as half the effort at angular velocities of 30°/s and 60°/s twice, respectively, with an interval of 45 min. The moment of force-time diagrams were collected. The 200 subjects were randomly divided into the training set （140 subjects） and the testing set （60 subjects）. The moment of force-time diagrams from subjects in the training set were used to train CNN model, and then the fully trained model was used to predict types of curves from the testing set. Random sampling of subjects along with subsequent development of models were performed 3 times. Results Under the circumstances of isokinetic knee exercises with maximal effort and half the effort, 2 400 moment of force-time diagrams were produced, respectively. Classification accuracy rates of the CNN models after the 3 trainings were 91.11%, 90.49% and 92.08%, respectively, and the average accuracy rate was 91.23%. Conclusion The CNN models developed in this study have a good effect on differentiating isokinetic moment of force-time diagrams of maximal effort exercises from those made with half the effort, which can contribute to identifying levels of efforts exerted by subjects during isokinetic knee exercises.

Characterization of the complete mitochondrial genome of Corvus corone orientalis

In this study, the complete mitochondrial genome of Corvus corone orientalis was assembled through next-generation sequencing data. This circular mitochondrial genome of C. corone orientalis is 16,947 bp in length and has a base composition of A (30.8%), T (24.7%), C (29.9%), and G (14.5%), demonstrating a bias of higher AT content (55.5%) than GC content (44.5%). The mitochondrial genome contains a typically conserved structure among bird mitogenomes, encoding 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNA), two ribosomal RNA genes (12S rRNA and 16S rRNA), and a control region (D-loop region). Except ND6, all other PCGs were located on the H-strand. ATP8 gene and ATP6 gene were overlapped by 8 bp. The whole mt genome of C. corone orientalis and other Corvoidea mitogenomes (24 species, in total) were used for phylogenetic analysis. The result indicated C. corone orientalis has the closest relationship with Corvus cornix cornix (NC_024698) and clustered within clade of genus Corvus.

Characterization of the complete mitochondrial genome of band-rumped Storm-petrel, Hydrobates castro

In this study, the complete mitochondrial genome of band-rumped Storm-petrel, Hydrobates castro, was determined through sequencing of PCR fragments. The complete mitochondrial genome of H. castro was 17,065 bp in length and encoded 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and two ribosomal RNA genes. The overall nucleotide composition is: 30.4% A, 24.5% T, 30.9% C, and 14.2% G, with a total G + C content of 45.1%. By phylogenetic analysis using Bayes method, H. castro showed the closest relationship with the white-faced storm petrel (Pelagodroma marina).

[Value of LSR and ADCs in differential diagnosis of hilar and mediastinal lymph nodes in lung cancer]

Objective: To evaluate the value of minimum ADC(ADC(min))and mean ADC(ADC(mean)), lesion to spinal cord signal intensity ratio (LSR) in diagnosis of metastatic hilar and mediastinal lymph nodes in patients with lung cancer. Methods: A total of 34 patients (89 lymph nodes) pathologically diagnosed as lung cancer were enrolled into this study who were examined in the Second Affiliated Hospital of Nantong University from January 2016 to June 2017. All patients underwent MRI scan 1 week before surgery or endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The short-axis diameter, ADC(mean) and ADC(min) of lymph nodes were measured and recorded respectively by two radiologists.The signal intensity of lymph nodes and spinal cord was also measured on DWI images (b=800 s/mm(2)). According to pathological findings, all lymph nodes were divided into metastasis group (58 lymph nodes) and non-metastasis group(31 lymph nodes). An independent sample t-test was used to compare the differences between the two groups of short-axis diameter, LSR, ADC(mean) and ADC(min) between two groups.The diagnostic performance of short-axis diameter, LSR, ADC(mean) and ADC(min) was analyzed by ROC curves. Results: There were significant differences in short-axis diameter, ADC(mean), ADC(min) and LSR values between two groups (all P<0.01). The short-axis diameter and LSR of the metastatic group were higher than that in non-metastasis group, while ADC(mean) and ADC(min) in metastatic group were lower than that in non-metastasis group.The ROC curve analysis showed that ADC(mean), ADC(min) and LSR achieved excellent but comparable diagnostic performance with an AUC of 0.977, 0.972 and 0.941, respectively (P<0.05). While the short-axis diameter of lymph nodes demonstrated poor diagnosis performance with an AUC of 0.798 (P<0.05). The thresholds of short-axis diameter, ADC(mean), ADC(min) and LSR were 9.86 mm, 1.88×10(-3) mm(2)/s, 1.57×10(-3) mm(2)/s and 0.80, respectively.Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for ADC(mean) were 96.6%, 90.3%, 94.9%, 93.3% and 94.4%, respectively, and those for ADC(min) were 98.3%, 90.3%, 95.0%, 96.6% and 94.4%, respectively, those for LSR were 91.4%, 90.3%, 94.6%, 84.8% and 89.9%, respectively, while those for short-axis diameter were 79.3%, 71.0%, 83.6%, 64.7% and 76.4%, respectively.There were significant differences in the area under the ROC curve between short-axis diameter and LSR, short-axis diameter and ADC(mean), short-axis diameter and ADC(min) (P<0.05). But there was no significant difference in the area under ROC curve between LSR and ADC(mean), LSR and ADC(min), ADC(mean) and ADC(min) (P>0.05). Conclusion: LSR, ADC(min) and ADC(mean) are the reliable parameters for the differentiation of metastatic and non-metastatic lymph nodes in lung cancer patients, and have good performance.

Characterization of the complete mitochondrial genome of Notospermus geniculatus

In this study, the complete mitochondrial genome of Notospermus geniculatus, was recovered through Illumina sequencing data. This complete mitochondrial genome of N. geniculatus is 15,180 bp in length and has a base composition of A (14.4%), T (41.3%), C (14.6%), G (29.6%), demonstrating a bias of higher AT content (55.7%) than GC content (44.2%). The mitochondrial genome contains a typically conserved structure among Lineidae mitogenomes, encoding 13 protein-coding genes (PCGs), 23 transfer RNA genes (tRNA), 2 ribosomal RNA genes (12S rRNA and 16S rRNA), and a control region (D-loop region). All PCGs were located on the H-strand. ND4L gene and ND4 gene were overlapped by 6 bp. The whole mt genome of N. geniculatus and other Protostomia mitogenomes (17 species, in total) were used for phylogenetic analysis. The result indicated N. geniculatus has the closest relationship with Lineus viridis (FJ839919.1) and clustered within Heteronemertea Clade, which representing a distinct order.

Characterization of the complete mitochondrial genome of three-spined stickleback, Gasterosteus aculeatus

In this study, the complete mitochondrial genome of three-spined stickleback, Gasterosteus aculeatus, was determined through sequencing of PCR fragments. The complete mitochondrial genome of G. aculeatus was 16,543 bp in length and encoded 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and two ribosomal RNA genes. The overall nucleotide composition is: 27.0% A, 28.4% T, 27.4% C, and 17.2% G, with a total G + C content of 44.6%. By phylogenetic analysis using ML method, G. aculeatus showed the closest relationship with the blackspotted stickleback (Gasterosteus wheatlandi).

Characterization of the complete mitochondrial genome of short-tailed field vole, Microtus agrestis

In this study, the complete mitochondrial genome of short-tailed field vole, Microtus agrestis, was determined through sequencing of PCR fragments. The complete mitochondrial genome of M. agrestis was 16,538 bp in length and encoded 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and two ribosomal RNA genes. The overall nucleotide composition is: 15.7% A, 27.5% T, 25.5% C, and 31.4% G, with a total G + C content of 56.9%. By phylogenetic analysis using Bayesian method, M. agrestisa showed the closest relationship with the southern vole (Microtus rossiaemeridionalis).

Characterization of the complete mitochondrial genome of Cassin's auklet, Ptychoramphus aleuticus

In this study, the complete mitochondrial genome of Cassin’s auklet, Ptychoramphus aleuticus, was determined using Illumina sequencing. The complete mitochondrial genome of P. aleuticuss was 16,524 bp in length and encoded 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and 2 ribosomal RNA genes. The overall nucleotide composition is: 30.8% A, 24.4% T, 30.6% C, and 14.2% G, with a total G + C content of 44.8%. By phylogenetic analysis using ML method, P. aleuticuss clustered with two Synthliboramphus species that belong to Alcidae.

Characterization of the complete mitochondrial genome of cape elephant shrew, Elephantulus edwardii

In this study, the complete mitochondrial genome of cape elephant shrew, Elephantulus edwardii, was determined through sequencing of PCR fragments. The complete mitochondrial genome of E. edwardii was 16,552 bp in length and and encoded 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and two ribosomal RNA genes. The overall nucleotide composition is: 32.7% A, 29.5% T, 25.0% C, and 12.9% G, with a total G+C content of 37.9%. By phylogenetic analysis using Bayesian method, E. edwardii showed the closest relationship with another Elephantulus speceis (Genbank accession: AB096867.1).

[Current status and prospect of photodynamic therapy in laryngeal diseases]

Laryngeal diseases are closely related to the swallowing and speech function of the patients.Protecting and restoring laryngeal function, while curing lesions, is vital to patients' quality of life.Photodynamic therapy (PDT) is a minimally invasive method which is widely used in the treatment of tumor, precancerous lesions, and inflammatory diseases.In recent years, it has been shown to have a protective effect on normal structures. This article reviews the clinical outcomes of laryngeal diseases treated with PDT since 1990 in order to evaluate its efficacy and significance. The complete remission rate of early-stage laryngeal tumors and precancerous lesions after PDT is 77.6%(249/321), and a promising effect on recurrent laryngeal papillomatosis has been observed thus far. The prolonged adverse effects of the first-generation photosensitizers have limited the application of PDT. With the improvement of photosensitizers and treatment strategies, PDT promises to be a safe, effective, and minimally invasive treatment method for laryngeal diseases.

[Impacts of early metoprolol intervention on connexin 43 and phosphorylated connexin 43 expression in rabbits with experimental myocardial infarction]

Objective: To investigate the early intervention effects of metoprolol on connexin 43(Cx43) and phosphorylated Cx43 (p-Cx43) expression in rabbits with post myocardial infarction. Methods: A total of 24 adult male New Zealand white rabbits were divided into sham group (n=6), early treatment group(n=6), routine treatment group(n=6), and myocardial infarction group(n=6) with a randomized block design blocked by weight. Myocardial infarction was induced by left anterior descending coronary artery (LAD) ligation. Rabbits in sham group received similar surgical procedure without LAD ligation. Metoprolol (12.5 mg/kg dissolved in 2 ml distilled water) was applied to rabbits in early treatment group and routine treatment group per gavage immediately after recovery from anesthesia and at 24 hours after myocardial infarction, respectively, then treated daily for 40 days. Rabbits in sham group and myocardial infarction group received 2 ml distilled water per gavage daily for 40 days. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) level were detected by automatic biochemistry analyzer after 6 hours in all rabbits. Ventricular fibrillation threshold (VFT) was measured in vivo by bipolar pacing electrodes at 40 days. Cx43 and p-Cx43 distribution in ventricular tissue was detected by immunofluorescence analyses. Cx43 and p-Cx43 protein level in ventricular tissue was determined by Western blot. Results: (1) Plasma LDH ((851.7±85.9)U/L vs. (332.3±39.6)U/L, P<0.01) and CK ((1 192.7±105.3)U/L vs. (462.3±65.6)U/L, P<0.01) were significantly higher in myocardial infarction group than in sham group (both P<0.01). (2) VFT was significantly lower in myocardial infarction group than that in sham group ((470.0±91.0) beats per minute vs. (683.3±60.9) beats per minute, P<0.05), and VFT was significantly higher in early treatment group ((633.3±43.2) beats per minute) and routine treatment group ((645.0±30.8) beats per minute) than in the myocardial infarction group (both P<0.05). (3) Immunofluorescence analyses showed that Cx43 was mainly localized in the intercalated disk, which was perpendicular to the cell long axis with linear arrangement, and less lateral distribution in sham group, early treatment group and routine treatment group, which was significantly different as the case in the myocardial infarction group. The expression of p-Cx43 in myocardial infarction group was less than in sham group, which was significantly upregulated in in early treatment group and routine treatment group when compared with myocardial infarction group, and expression of p-Cx43 was significantly higher in early treatment group than in routine treatment group. (4)The p-Cx43/Cx43 ratio of protein was significantly lower in myocardial infarction group than in sham group (0.165±0.011 vs. 0.363±0.046, P<0.05), and significantly higher in early treatment group (0.720±0.063) and routine treatment group (0.364±0.030) than in myocardial infarction group (both P<0.05), and this ratio was significantly higher in early treatment group than in routine treatment group (P<0.05). Conclusion: Metoprolol treatment, especially the early metoprolol treatment (within 24 hours after LAD ligation), could significantly improve VFT by ameliorating the distribution and dephosphorylation of myocardial Cx43 in rabbits with experimental myocardial infarction.

Development of an enzyme-linked immunosorbent assay for detection of clopidol residues in chicken tissues

BACKGROUND

Clopidol is mainly used for the prevention and treatment of coccidiosis, which poses a serious potential hazard to public health, in veterinary medicine. The aim of this study was to prepare monoclonal antibodies (mAbs) against clopidol (CLOP) and develop an immunoassay for detecting CLOP residues in chicken tissues. After derivation, CLOP hapten was conjugated to carrier proteins to synthesize the artificial antigen, and immunized Balb/C mice were employed to screen mAbs.

RESULTS

A sensitive hybridoma named C1G3 was screened out and two indirect competitive enzyme-linked immunosorbent assay (icELISA) standard curves were established. For the traditional two-step assay the linear range was from 0.06 to 98 ng mL(-1) , with half-maximal inhibitory concentration (IC50 ) and limit of detection (LOD) values of 2.76 ng mL(-1) and 0.03 ng mL(-1) respectively, while the rapid one-step icELISA had a working range from 0.08 to 102 ng mL(-1) , with IC50 and LOD values of 3.52 ng mL(-1) and 0.03 ng mL(-1) respectively. It was also indicated that a 10-fold dilution in chicken muscles gave an inhibition curve almost the same as that obtained in phosphate-buffered saline. When applied to spiking tests in chicken samples, the correlation coefficient (R(2) ) between concentrations added and measured was 0.9534.

CONCLUSION

The results of this study suggest that the immunoassay described is a promising alternative for screening CLOP residues in biological matrices and is suitable for routine diagnostics.

Damaging effects of water-borne cadmium chloride on DNA of lung cells of immature mice

We investigated the effects of cadmium on lung cell DNA in immature mice. The mice were randomly divided into four groups: control group, low-dose group (1/100 LD(50)), middle-dose group (1/50 LD(50)), and high-dose group (1/25 LD(50)); they were supplied with cadmium chloride or control water for 40 days. Lung cells collected from sacrificed mice were used to evaluate the extent of DNA damage by comet assay. The ratio of tailing cells, DNA tail length, DNA comet length, DNA tail moment, DNA olive tail moment, and percentage of DNA in the comet tail were measured. The rate of tailing lung cells exposed to cadmium increased significantly; the low-concentration group had significantly (P < 0.05) higher rates, and the middle- and high-concentration groups had higher (P < 0.01) rates compared to the control. DNA tail length, DNA comet length, DNA tail moment, and DNA olive tail moment all increased with the increase in cadmium doses, but compared with those of the control group, no significant differences in low-dose group were found (P > 0.05), and the differences in middle- and high-dose groups were all highly significant (P < 0.01). The degree of DNA damage also increased with the increase of the cadmium concentrations. We conclude that cadmium significantly increases DNA damage in lung cells of immature mice in a dose-dependent manner.

Production and characterisation of monoclonal antibodies against 19-Nortestosterone

OBJECTIVE

To produce anti-19-Nortestosterone (NT) monoclonal antibodies and identify their immunological characteristics.

METHODS

Hybridomas were prepared by fusing NS0 mouse myeloma cells with splenocytes isolated from immunized BALB/c mice. Noncompetitive and competitive indirect ELISA were employed to screen positive cell clones. A caprylic acid ammonium sulphate (CAAP) method was used to purify NT mAb, and the Batty saturation method was used to determine the affinity constant (Kaff).

RESULTS

Five hybridoma cell lines, named NT-1, NT-2, NT-3, NT-4, and NT-5, were identified and their corresponding mAbs were of the IgG(1) isotype with a k light chain. The Kaffs of all mAbs were between 2.6 and 4.7 × 10(9) L/mol. The titers and IC(50) values of purified ascite fluids were in the range of (0.64-2.56) × 10(5) and (0.55-1.0) ng/mL, respectively. Of all the cross-reacting steroids, (-NT was the most reactive with the mAbs at 62% with NT-1 mAb and 64% with NT-2 mAb. Negligible cross-reactivity (<0.01%) with other steroids was observed.

CONCLUSION

The establishment of these hybridomas allows the potential development of a rapid test kit, and may provide an alternative method for the detection of NT residues in food producing animals.

Effect of ultrasonic and alkaline pretreatment on sludge degradation and electricity generation by microbial fuel cell

Both ultrasonic and alkaline pretreatment of excess sewage sludge were investigated to enhance organic degradation and electricity generation from sludge by the subsequent microbial fuel cell (MFC). The ultrasonic pretreatment showed that the degree of sludge disintegration was directly related to the energy input, ultrasonic density and duration. Alkaline pretreatment demonstrated that more soluble organic matters were released from the sludge with more NaOH dose and longer reaction time, and the degree of sludge disintegration within 30 min accounted for 45-76% of that for 24 h. When ultrasonic and alkaline pretreatment were combined, the released chemical oxygen demand (COD) was higher than those with ultrasonic or alkaline pretreatment alone. Ultrasonic and alkaline (pH=11) pretreatment could enhance electricity generation from sludge by the subsequent MFC, resulting in more degradation of total COD (TCOD) and volatile solids (VS). Slight change in power output from the MFC was observed due to the higher soluble chemical oxygen demand (SCOD) in the pretreated sludge. By using the combined ultrasonic and alkaline pretreatment of sludge, the removal efficiencies of TCOD and VS were increased from 27.1% to 61.0% and 35.2% to 62.9% in comparison with raw sludge, respectively, and the power output in MFC was slightly increased from 10.3 W/m(3) to 12.5 W/m(3).

Pharmaceutical residues in wastewater treatment works effluents and their impact on receiving river water

Various pharmaceutical residues are being discharged from wastewater treatment works (WTW) effluents, the impact of which on river water quality is of high relevance to environmental risk assessment. The concentrations of eleven pharmaceutical compounds were determined in three WTWs in England, and the river Ouse receiving effluents from Scaynes Hill WTW. Results show that five compounds propranolol, sulfamethoxazole, carbamazepine, indomethacin and diclofenac were detected in all wastewater and river water samples, with carbamazepine showing the highest concentrations (up to 2336 ng L(-1)) in WTW influent. Different compounds were removed to different extent in the WTWs, varying from 43 to 92%, with the highest performance obtained by the WTW with tertiary treatment (sand filtration). The pharmaceutical residues from Scaynes Hill WTW were eventually discharged into the river Ouse, causing an elevation in their concentrations downstream of the outfall. This was confirmed by the good agreement between measured concentrations and those predicted by a simple dilution model.

Continuous electricity production from leachate in a novel upflow air-cathode membrane-free microbial fuel cell

In this study, a novel microbial fuel cell, i.e. upflow air-cathode membrane-free microbial fuel cell (UAMMFC) was reported and its performance in electricity generation from original leachate was examined. The experimental results demonstrated that the UAMMFC could continuously generate electricity from leachate (0.3V; REX=150 Omega) for an operational period of time (50 h). The maximum volumetric power reached 12.8 W/m3 at current density of 41 A/m3 (93 Omega). NH4+-N elimination from the leachate was shown to be a consequence of electrochemistry-independent oxidation occurred in the MFC. Increasing organic loading rate from 0.65 to 5.2 kgCOD/m3 d resulted in a decrease of overall Coulombic efficiency (CE) from 14.4% to 1.2%. The low CE obtained here should be attributed to severe oxygen diffusion from the open-to-air cathode.

Research progress in the use of ferrate(VI) for the environmental remediation

The aim of this paper is to review the research progress of using ferrate(VI) in following fields of environmental remediation: (1) water disinfection; (2) degradation of synthetic organic pollutants; (3) treatment of emerging organic pollutants; (4) oxidation of inorganic pollutants; (5) removing humic substance; (6) wastewater treatment and disinfection; and (7) sewage sludge treatment. Whilst the superior performance of potassium ferrate(VI) as an oxidant/disinfectant for the environmental remediation has been demonstrated in various recent researches, challenges have existed to the implementation of ferrate(VI) technology in full-scale water, wastewater and sewage sludge treatment owing to either the instability property of a ferrate(VI) solution or a high preparation cost of a solid ferrate(VI). In addition to this, there are some fundamental issues which have not yet been studied thoroughly which are crucial for the implementation of ferrate(VI)-these lead to the future research work recommended by this paper.

Removal of boron (B) from waste liquors

This paper explores the use of electrocoagulation to remove boron from waste effluent in comparison with alum coagulation. In treating model test wastes, greater boron removals were achieved with electrocoagulation at low doses than conventional alum coagulation when reaction was undertaken for the same conditions (pH 8.5, and initial boron concentration was 500 mg/L). Al electrocoagulation can achieve good boron removal performance (68.3%) at a dose of 2.1 (as molar ratio of Al:B, and for current density of 62.1 A/m2), while alum coagulation can only achieve the maximum boron removal of 56% at a dose of 2.4. Also, Al electrocoagulation can remove 15-20% more boron than alum coagulation for the same dose compared in the treatment of both model test wastes and industry effluent. The estimation of running costs shows that to achieve 75% boron removal from industry waste effluent, i.e. removing 150 g of boron from 1 m3 of effluent, electrocoagulation was 6.2 times cheaper than alum coagulation. The economic advantage of electrocoagulation in the treatment of boron-containing waste effluent is thus significant.

Occurrence and treatment trials of endocrine disrupting chemicals (EDCs) in wastewaters

This study demonstrates that both synthetic and natural endocrine disrupting chemicals (EDCs) (e.g., bisphenol A, estrone and 17beta-estradiol) were found in the crude wastewaters from two wastewater treatment works (WwTWs). Conventional biological processes can lower EDCs concentrations to several tens to hundreds ngl(-1). Since natural EDCs (e.g., estrone and 17beta-estradiol) have biological activity and adverse impact on the environment at extremely low concentrations (several tens of ngl(-1)), further treatment after conventional biological processes is required. Preliminary trials with ferrate(VI) and electrochemical oxidation process demonstrated that both processes can effectively reduce EDCs to very low levels, ranging between 10 and 100ngl(-1), but the former is more effective than the latter to reduce COD concentration in wastewater for given studying conditions.

A survey of endocrine disrupting chemicals in sewage and a preliminary treatment trial

This paper demonstrates that synthetic endocrine disrupting chemicals (EDCs) (e.g. bisphenol-A) and natural EDCs (e.g. estrone and 17beta-estradiol) were found in the crude sewage from two sewage treatment works. Conventional biological processes can lower EDC concentrations to several hundred nanograms per litre. Because natural EDCs (e.g. estrone and 17beta1-estradiol) have biological activity and an adverse impact on the environment at extremely low concentrations (several tens of nanograms per litre), and because the existing wastewater/sewage treatment processes are not adequate to reduce natural EDC concentrations lower than 100 ng L(-1), further treatment after conventional biological processes is required. Preliminary trials with ferrate (VI) and electrochemical oxidation processes demonstrated that the former is more effective than the latter in reducing EDC concentrations, and that both the processes can effectively reduce EDCs to very low levels, ranging between 20 and 100 ng L(-1).

Isolation, characterization and expression of 11beta-hydroxysteroid dehydrogenase type 2 cDNAs from the testes of Japanese eel (Anguilla japonica) and Nile tilapia (Oreochromis niloticus)

The Japanese eel (Anguilla japonica) and Nile tilapia (Oreochromis niloticus) 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) cDNAs were isolated from their respective testes cDNA libraries. The cDNAs predict two peptides of 436 and 406 amino acid residues that share about 42% homology with mammalian 11beta-HSD type 2 proteins. Analysis of the tissue distribution pattern by RT-PCR reveals that 11beta-HSD2 is expressed in a wide variety of tissues in tilapia, with higher expression in kidney and gill of both sexes, and with the highest expression in testis. 11beta-Dehydrogenase activity of the eel 11beta-HSD2 was confirmed by demonstrating the conversion of cortisol to cortisone by the recombinant protein after transient expression of this cDNA clone in COS-1 cells. Bands of approximately 2.7 and approximately 3.8 Kb were detected in Northern blot of eel and tilapia testes respectively, which is consistent with the cloned cDNA sizes of the two species. Northern blot analysis also revealed that the expression of the eel testis 11beta-HSD2 gene could be induced by human chorionic gonadotropin (hCG) injection, implying a role of 11beta-HSD2 in hCG-induced 11-ketotestosterone production and spermatogenesis in the Japanese eel.

[Application of BRL conditioned medium in ES cells culture]

AIM

To study the method of using BRL conditioned medium in ES cells culture.

METHODS

ES cells were cultured in BRL conditioned medium, MEF feeder layer, and BRL conditioned medium plus MEF feeder layer respectively. Both the numbers of ES cells and embryonic bodies and the differentiated cells around the ES cell colonies at certain stages were studied to find the differences of growing speed of ES cells in three culture mediums.

RESULTS

On promoting the growth and maintaining the undifferentiated state of ES cells at the early stage after recovery, the effects of BRL conditioned medium were less than those of MEF feeder layer and those of BRL conditioned medium plus MEF feeder layer (P < 0.01), and there was no difference between MEF feeder layer and BRL conditioned medium plus MEF feeder layer (P > 0.05).

CONCLUSION

ES cells should be cultivated on MEF feeder layer or in BRL conditioned medium plus MEF feeder layer at the early stage after recovering.

[The relationship between tongue and stability of complete mandibular denture]

OBJECTIVE

To explore the relationship between contour and functional movement of tongue and stability of complete mandibular denture.

METHODS

157 patients with middle to severe alveolar atrophy restored with complete mandibular denture were retrospectively reviewed. Of the patients, 139 cases had normal tongue, 11 had hypertrophic tongue, 2 had macroglossia and 5 had retrusive tongue. An appropriate impression position of tongue was obtained with limitation of lingual movement by individual tray with tongue orientation bar. In measurement of the vertical distance, the anterior wax rim did not contact with a small space. The mandible was used as the standard plane. The mandibular denture was first arranged. The occlusal plane of the mandible was 2-3mm inferior to the lingual margin at rest.

RESULTS

The patients were reexamined 1 month, 6 months and 1 year after rehabilitation with denture. 148 patients used the denture with satisfactory results. The tongue was mobile freely in accordance with the denture. Unsatisfactory results were present in 3 patients with hypertrophic tongue, 2 patients with macroglossia, 2 patients with retrusive tongue and 2 patients with severe mandibular alveolar atrophy.

CONCLUSION

The anatomic morphology and functional movement of tongue play an important role in the stability of the mandibular complete denture.

Removing arsenic from groundwater for the developing world--a review

This paper is principally concerned with summarising the experience to date of treating arsenic containing ground/surface water by oxidation, coagulation/precipitation and adsorption processes. Arsenic (As) has been verified through epidemiological evidence as one of the most carcinogenic and toxic substances in surface and ground water. Oxidation, coagulation/precipitation, and adsorption have been widely used in arsenic removal and the study results demonstrated that these technologies can remove arsenic from ground/surface water efficiently; the residual arsenic concentration in the effluent could be in the range of 5-10 pg/l, against the influent arsenic concentration in the range of 10-500 pg/l. However, these technologies need to be surveyed in order to validate the efficiency, cost and maintenance requirments by considering social and economic situations and the availability of the local resources in the developing world.

Eel (Anguilla japonica) testis 11beta-hydroxylase gene is expressed in interrenal tissue and its product lacks aldosterone synthesizing activity

A recombinant expression vector containing Japanese eel (Anguilla japonica) testis cytochrome P450(11 beta) (11beta-hydroxylase) cDNA was introduced into COS-1 cells. Enzymatic activity of the expressed P450(11 beta) for corticosteroid synthesis was analysed by incubating transfected cells with 14C-labelled 11-deoxycorticosterone or 3H-labelled deoxycortisol as substrates. Thin layer chromatography of incubation medium revealed that a high percentage of 11-deoxycorticosterone was converted into corticosterone and 11-dehydrocorticosterone but no aldosterone was detected. Similarly, deoxycortisol was converted into cortisol and cortisone. These results show that eel P450(11beta) does not possess significant aldosterone synthesizing activity. Northern blot analysis detected a 1.8 kb transcript of P450(11beta) using RNA extracted from interrenals of untreated Japanese eel but no hybridization signal was apparent using RNA extracted from brain, spleen, heart, muscle or testis. Immunohistochemistry using an antiserum against P450(11beta) also revealed strong immunostaining in interrenal cells.

Fish testicular 11beta-hydroxylase: cDNA cloning and mRNA expression during spermatogenesis

We isolated and characterized a cDNA encoding testicular 11beta-hydroxylase, cytochrome P450(11beta) from the Japanese eel (Anguilla japonica) testis. The cDNA contains an open reading frame that encodes a protein of 511 amino acids. The predicted amino acid sequence shares 38-48% homology with those of adrenal P450(11beta) from mammals and frog. Transient expression in COS 1 cells confirmed that the protein encoded by this cDNA had P450(11beta) activity. Northern blotting revealed a single 1.8 kb long transcript of P450(11beta). This transcript was not found in immature eel testes prior to an injection with human chorionic gonadotropin (hCG), but it was present in eel testes after hCG injection.