[Research status and outlook of deep learning in oral and maxillofacial medical imaging]

Artificial intelligence, represented by deep learning, has received increasing attention in the field of oral and maxillofacial medical imaging, which has been widely studied in image analysis and image quality improvement. This narrative review provides an insight into the following applications of deep learning in oral and maxillofacial imaging: detection, recognition and segmentation of teeth and other anatomical structures, detection and diagnosis of oral and maxillofacial diseases, and forensic personal identification. In addition, the limitations of the studies and the directions for future development are summarized.

[Research status and outlook of deep learning in oral and maxillofacial medical imaging]

Artificial intelligence, represented by deep learning, has received increasing attention in the field of oral and maxillofacial medical imaging, which has been widely studied in image analysis and image quality improvement. This narrative review provides an insight into the following applications of deep learning in oral and maxillofacial imaging: detection, recognition and segmentation of teeth and other anatomical structures, detection and diagnosis of oral and maxillofacial diseases, and forensic personal identification. In addition, the limitations of the studies and the directions for future development are summarized.

[Artificial intelligence in medical application: problems and legal countermeasures]

Artificial intelligence (AI) is widely used in the current medical field at home and abroad, including medical imaging, auxiliary diagnosis, drug research and development, health management, disease prediction and other fields, but its "autonomy" and "unknownness" have brought great challenges to the current legal system, especially the subject positioning of AI medical care and the identification of legal responsibilities. We should effectively analyze the development trend of the future role of AI medical care, put forward countermeasures in advance at the legal level to prevent problems before they occur targeting the problems of AI medical development, in order to promote the effective regulation of the application of AI medical care, and thus ensure its healthy development in China.

[Minimally invasive enucleation for benign and low-grade malignant pancreatic tumors: an analysis of 60 cases]

Objective: To investigate the safety and feasibility of minimally invasive pancreatic tumor enucleation. Methods: The clinicopathological data of 60 patients with minimally invasive pancreatic tumor enucleation admitted to the Department of Pancreatic Surgery of Fudan University Cancer Center from November 2019 to August 2021 were retrospectively analyzed. There were 17 males and 43 females,with age of (50.0±13.2)years(range: 23 to 73 years). Tumors were located in the head of pancreas in 40 cases(66.7%),neck and tail of pancreas in 20 cases(33.3%). Patients were divided into robotic group(n=25) and laparoscopic group(n=35) according to surgical methods. The measurement data were compared by t-test or Mann-Whitney U test, and the categorical data were compared by χ² test or Fisher exact probability method. The influencing factors of postoperative pancreatic fistula were analyzed by univariate and multivariate Logistic regression. Results: All patients successfully completed tumor enucleation without conversion to laparotomy. The operation time was (183.5±67.3)minutes(range:90 to 410 minutes). Twelve patients(20.0%) underwent stent placement and pancreatic duct repair during operation. The removal time of abdominal drainage tube after operation was (24.7±22.9)days(range:2 to 113 days). The tumor diameter in the robotic group was larger than that in the laparoscopic group((3.5±0.9)cm vs. (2.9±0.7)cm,t=-2.825,P=0.006). The incidences of postoperative biochemical fistula and grade B pancreatic fistula were 20.0%,22.9% and 36.0%,51.4%,respectively(χ²=2.289,P=0.318). There were no grade C pancreatic fistula,lymphatic fistula,biliary fistula,delayed gastric emptying,secondary operation and perioperative death in both groups. Multivariate logistic regression analysis was performed on the occurrence of clinically related pancreatic fistula(above grade B). The results showed that the increase of body mass index(OR=1.285,95%CI:1.053 to 1.569,P=0.014),the larger diameter of the tumor(OR=3.703,95%CI:1.465 to 9.360,P=0.006) and intraoperative pancreatic duct repair(OR=7.889,95%CI:1.471 to 42.296,P=0.016) were independent risk factors,whereas robotic surgery(OR=0.168,95%CI:0.036 to 0.796,P=0.025) was a protective factor. No case of pancreatin dependent dyspepsia and new onset diabetes mellitus was observed. Conclusions: Minimally invasive tumor enucleation is feasible in the treatment of benign and low-grade pancreatic tumors. The incidence of pancreatic fistula is high in the short term after operation,but serious complications are rare. The robot assisted system can reduce the risk of postoperative pancreatic fistula and has more advantages in dealing with larger diameter tumors because of clearer surgical vision and more accurate operation.

[Effect of laparoscopic surgery for pancreatic cancer after neoadjuvant chemotherapy]

Objective: To evaluate the safety and feasibility of laparoscopic surgery after neoadjuvant chemotherapy for pancreatic cancer. Methods: Clinical data of 8 patients underwent laparoscopic surgery after neoadjuvant chemotherapy for pancreatic cancer at Fudan University Shanghai Cancer Center from September 2019 to June 2020 were reviewed retrospectively. There were 5 males and 3 females,aged from 47 to 72 years old. All patients underwent abdominal enhanced CT and PET-CT before operation to accurately evaluate the tumor stage and exclude distant metastasis. Results: Neoadjuvant chemotherapy with AG regimen(gemcitabine 1 000 mg/m² and albumin bound paclitaxel 125 mg/m²) was received for 2 to 6 cycles before surgery. All 8 patients successfully completed the operation,including 5 cases of pancreaticoduodenectomy,2 cases of radical antegrade modular pancreatosplenectomy(RAMPS),and 1 case of total pancreatectomy. No conversion to laparotomy or laparoscopic assisted surgery. The operation time was 240 to 450 minutes,the blood loss was 100 to 500 ml,the postoperative length of stay was 10 to 16 days. During the follow-up period up to December 31, 2020, there was 1 case suffered grade B pancreatic leakage and abdominal infection. The numbers of resected lymph nodes were 9 to 31. All patients received R0 resection. The follow-up times were 4.5 to 9.5 months. One patient underwent RAMPS was diagnosed as liver metastasis after 2 months of the operation,and the other 7 patients still survived without tumor recurrence. Conclusion: Minimally invasive surgery of pancreatic cancer after neoadjuvant chemotherapy is safe and feasible in experienced pancreatic minimally invasive centers.

Polymorphism, expression and structure analysis of key genes in the ovarian steroidogenesis pathway in sheep (Ovis aries)

Background

Litter size is an important factor that significantly affects the development of the sheep industry. Our previous TMT proteomics analysis found that three key proteins in the ovarian steroidogenesis pathway, STAR, HSD3B1, and CYP11A1, may affect the litter size trait of Small Tail Han sheep.

Objective

The purpose of this study was to better understand the relationship between polymorphisms of these three genes and litter size.

Material and Method

Sequenom MassARRAY detected genetic variance of the three genes in 768 sheep. Real‐time qPCR of the three genes was used to compare their expression in monotocous and polytocous sheep in relevant tissues. Finally, bioinformatics analysis predicted the protein sequences of the different SNP variants.

Result

Association analysis showed that there was a significant difference in litter size among the genotypes at two loci of the CYP11A1 gene (p < 0.05), but no significant difference was observed in litter size among all genotypes at all loci of the STAR and HSD3B1 genes (p > 0.05). However, STAR expression was significantly different in polytocous and monotocous sheep in the pituitary (p < 0.01). Tissue‐specific expression in the ovary was observed for HSD3B1 (p < 0.05), but its expression was not different between polytocous and monotocous sheep. Bioinformatics analysis showed that the g.33217408C > T mutation of CYP11A1 resulted in major changes to the secondary and tertiary structures. In contrast, gene polymorphisms in STAR and HSD3B1 had minimal impacts on their protein structures.

Discussion

This may explain why the CYP11A1 variant impacted litter size while the others did not. The single nucleotide polymorphism of the CYP11A1 gene would serve as a good molecular marker when breeding to increase litter size in sheep. Our study provides a basis for further revealing the function of the ovarian steroidogenesis pathway in sheep reproduction and sheep breeding.

[Application of portable electroencephalograph in patients with epilepsy and establishment of medical platform]

Objective: To provide a portable electroencephalograph that can facilitate long-term monitoring of epilepsy patients outside the hospital, and establish a medical platform for epilepsy data monitoring and treatment. Methods: From June 2018 to October 2019, twenty-nine patients from Huashan Hospital (superior hospital) and Jing'an District Central Hospital (subordinate hospital) of Fudan University were enrolled in the study. Among them, twenty-eight cases were diagnosed with epilepsy and 1 case was epileptic seizure. Electroencephalogram (EEG) was collected by portable electroencephalograph once a week and followed up for three months. The seizure frequency, seizure form, medication type, EEG lead number and positive rate were recorded. Patients' medical records and EEG data were uploaded to the cloud database to build a medical alliance platform. Doctors of different levels of hospitals couldobtain diagnosis and achieve resource sharing based on the platform. The data was statistically analyzed using SPSS 18.0. Results: The EEG data collected by the portable electroencephalograph hadfewer artifacts, complete sleep cycle, and could record the interictaldischarges. Twenty-nine patientsunderwent a total of 148 EEG monitoring during the three-month follow-up. Eighty-five cases of epileptic discharges were detected, and the EEG positive rate was 57.4%. The positive rate of EEG in patients with generalized seizures (84.9%) was higher than that in patients with focal seizures (42.1%) (P<0.01); the positive rate of EEG in patients with 2-3 antiepileptic drugs and patients with frequent seizures within three months were also higher (P<0.05). Doctors in the superior hospital in the platform make diagnosis and treatment suggestions according to the above data. Elevenseizure-free patients and four patients with fewer seizures and discharges were diverted to the community hospital for follow-up. Fourteen patients with poor seizure control and/or continuous epileptic discharges were diverted to the superior hospitalto adjust the medication. Doctors of subordinate hospital acquired the diagnosis and treatment suggestions through the platform, and then strengthened the daily care and follow-up. Conclusion: Combined with a portable electroencephalograph, the current study establishs a medical platform for patients with epilepsy to achieve long-term monitoring and rational use of medical resources.

[MRI histogram texture analysis of lateral pterygoid muscle in patients with temporomandibular disorders]

Objective: To evaluate the functional changes of lateral pterygoid muscle (LPM) in the patients with temporomandibular disorders (TMD) using histogram texture analysis. Methods: A total of 28 TMD patients, including 15 males and 13 females, aged (26.2±12.1) years (15-62 years), were enrolled in the outpatient clinic of Department of Radiology, Hainan Hospital of Chinese PLA General Hospital from May 2016 to April 2020. At the same time, 13 volunteers with normal temporomandibular joint [6 males and 7 females, aged (23.5±3.3) years (20-30) years] were recruited. All participants were performed with temporomandibular joint MRI scan, and the subjects were classified into 3 groups according to the disc displacement: TMD with disc without displacement (TMD-DwoD), TMD with disc displacement without reduction (TMD-DDwoR) and NC with disc displacement without reduction (NC-DwoD) for each temporomandibular joint. The area, signal intensity, coefficient of variation (CV) of mean signal intensity and histogram texture of the superior belly of LPM (SBLPM) and inferior belly of LPM (IBLPM) were measured using regions of interests. Results: The area of SILPM presented significantly smaller in TMD-DwoD [(67.36±30.23) mm²] compared with that in NC-DwoD [(91.42±45.01) mm²] (P<0.05) and in TMD-DDwoR group [(72.27±37.53) mm²] (P>0.05). The mean signal intensity of SBLPM was identified significantly higher in TMD-DwoD (304.20±29.90) and TMD-DDwoR (315.06±40.20) compared with that in NC-DwoD (269.79±25.54) (P<0.05). The CV of mean signal intensity of SBLPM presented significantly higher in TMD-DwoD (8.89±2.60) compared with that in NC-DwoD (6.76±1.82) and TMD-DDwoR (7.63±1.62) (P<0.05). The skew and kurtosis showed no significantly differences among three groups for SBLPM (P>0.05). The mean signal intensity and CV for IBLPM presented significantly higher in TMD-DwoD (286.69±23.48 and 9.96±2.24, respectively) and TMD-DDwoR (275.98±30.55 and 10.25±1.96, respectively) compared with that in NC-DwoD (243.56±17.04 and 8.49±1.94, respectively) (P<0.05). The skewness showed significantly lower in TMD-DwoD (0.90±0.94) and TMD-DDwoR (0.73±0.97) compared with that in NC-DwoD (1.40±1.03) (P<0.05). The area and kurtosis for IBLPM showed no significant differences among three groups (P>0.05). Conclusions: The MR histogram texture analysis could primarily be considered as a tool to evaluate the LPM function in TMD patients.

[Three-dimensional quantitative evaluation of condylar bone remodeling of temporomandibular joint based on cone-beam CT imaging]

Objective: To establish a three-dimensional （3D） quantitative measurement and evaluate the condylar bone remodeling of temporomandibular joint (TMJ). Methods: Pre-and post-treatment cone-beam CT (CBCT) data were obtained from 41 patients ［10 males, 31 females, mean age of (19.7±4.4) years (12-30 years old)］, who visited the Center for TMD and Orofacial Pain, Peking University School and Hospital of Stomatology from November 2014 to August 2019, and diagnosed with acute disc displacement without reduction or disc displacement with reduction, with intermittent locking and treated by manual disc reduction followed by anterior repositioning splint. First, condylar bone remodeling was evaluated according to the number of "double contour image" and qualitatively classified as no remodeling (no double contour image), partial remodeling (1-4 double contour images) and remarkable remodeling (5-6 double contour images). Then, condylar bone remodeling was quantitatively evaluated by CBCT based 3D measurement: segmenting condylar images using a semi-automatic method of the manually preliminary mark combined with watershed algorithm, reconstructing the surface models, superimposing the pre-and post-treatment condylar images and finally calculating the volumetric differences of condyle and condylar head, respectively. Results: The Kappa values of two-dimensional (2D) qualitative evaluation were 0.66-0.87, and 3D quantitative measurements of condyle and condylar head volume were also reliable, with the intraclass correlation coefficient (ICC) values of intra-observer 0.998/0.941 and inter-observer 0.999/0.942 respectively. The volumetric increment of the condyle and condylar head after treatment was (41.7±90.2) mm³ and (62.8±70.9) mm³, respectively. Eighty-two condyles were divided into three sub-groups: no remodeling (21), partial remodeling (20) and remarkable remodeling (41). Ranking of the volumetric increment of the condyle and condylar head after treatment was as follows: remarkable remodeling group>partial remodeling group>no remodeling group (P<0.05). Conclusions: The 3D quantitative measurement for evaluating condylar bone remodeling had excellent consistency and reliability, which was consistent with the qualitative classification for condylar bone remodeling. The condylar head as a region of interest was more sensitive to the volumetric changes.

[Evaluation of brain volume changes in patients with painful temporomandibular disorders using voxel-based morphometry]

Objective: To evaluate the altered brain volume of the patients with painful temporomandibular disorders (TMD) using voxel-based morphometry (VBM). Methods: One hundred forty-six TMD patients ［age (36.8±15.8) years, male/female=44/102］ and 193 normal controls (NC) ［age (43.3±15.6) years, male/female = 92/101］ were performed with 3 dimensional brain structural images at 3.0 T MR scanner from November 2011 to December 2019 in Department of Radiology, Hainan Hospital and General Hospital of Chinese PLA. The brain structural images were segmented into gray matter, white matter and cerebrospinal fluid, and the gray matter images were performed with two-samples t-test with total intracranial volume, age and gender as covariates. Results: The gray matter volume (GMV) presented significantly higher in TMD group ［(632.4±65.4) ml］ than that in NC group ［(596.1±76.3) ml］ (t=4.70, P<0.05). The brain regions with increased GMV for TMD located in left inferior temporal gyrus, bilateral fusiform gyrus, bilateral middle temporal gyrus and right lingual gyrus compared with NC. Conclusions: The temporal lobe was the targeting brain region for TMD patients with increased GMV, which should further be investigated to elucidate the neuromechanism.

[To evaluate the disk position of the temporomandibular joint using calcium suppressed spectral-based CT images in the patients with temporomandibular disorder]

Objective: To evaluate the application of calcium suppressed (CaSupp) spectral CT technique in evaluating disk position and measuring the thickness of the posterior band of temporomandibular joint (TMJ). Methods: The twenty-three temporomandibular disorder patients [mean age 23(12~62) years, male/female=14/9] were performed with oblique sagittal and coronal proton density weighted imaging (PDWI) and spectral CT scans from February to July, 2019 in Department of Radiology, Hainan Hospital of General Hospital of Chinese PLA, and 45 TMJ joints were evaluated. The subjects were classified into two groups according to the scanning modalities: MRI measurement group and CaSupp spectral-based CT group. The CaSupp technique were applied with the spectral-based CT images and CaSupp images were generated. The oblique sagittal and coronal CaSupp imaged were reformatted by perpendicular to the long axis of the condyle. The TMJ disk positions were evaluated on oblique sagittal and coronal images, and the maximal disk thickness were measured on the oblique sagittal images. Results: The joint position was basically consistent on MRI and CaSupp images for the 45 TMJ joints. The intra-class coefficient value was 0.843 (0.712, 0.914) for the measurement of the posterior band of the TMJ disk between MRI and CaSupp images. Bland-Altman presented that the [95.6% (43/45)] points with the difference located in the 95% agreement interval. Wilcoxon paired text demonstrated that there was no significant different for the thickness of the posterior band between MRI [2.57 (1.76, 3.65) mm] and CaSupp images [2.67 (1.74, 4.56) mm] (P=0.07). Conclusions: The CaSupp spectral-based CT could be used to evaluated the TMJ disk position and the thickness of the posterior band.

[MRI observation of condylar location and morphology in the patients with temporomandibular disc displacement]

Objective: To evaluate the mandibular condylar location and morphology in the temporomandibular joint disorders. Methods: One hundred thirty-seven TMD patients (age 37.5±16.1 years, male/female=39/98) were performed with MRI scan for temporomandibular joint (TMJ) from November, 2011 to April, 2019 in Department of Radiology,Hainan Hospital of General Hospital of Chinese PLA and General Hospital of Chinese PLA. The patients were classified into 3 groups according the disc displacement: disc without displacement (DWoD) (185 TMJ), disc displacement with reduction (DDWR) (17 TMJ) and disc displacement without reduction (DDWoR) (72 TMJ). The location (anterior position, central position and posterior position) and morphology (oval shape, flat shape and beaklike shape) of the condylar head were observed on the sagittal PDWI, and the long and short axes were measured on the axial T2WI. Another groups were classified into 3 subgroups according to the disc displacement of bilateral TMJ: bilateral normal disc location (biND) (74 cases), unilateral disc displacement (uniDD) (40 cases) and bilateral disc displacement (23 cases). The inter-condyle angle was measured on the axial T2WI. Results: There was no significant difference for the location of condylar head among DWoD, DDWR and DDwoR groups (χ(2)=7.435, P=0.115). The rate for flat condylar shape was significantly higher in DWoD group [83.9%(115/137)] than that in DDWoR group [50.7%(34/67)], and the rate for beaklike condylar shape was significantly lower in DWoD group [16.1%(22/137)] than that in DDWoR group [49.3%(33/67)] (χ(2)=23.521, P<0.001). The length of long axis presented significantly longer in DWoD group [(17.2±2.4) mm] than that in DDWR group [(15.4±2.0) mm] and that in DDWoR group [(14.7±2.7) mm] (P<0.05). The length of short axis presented significantly longer in DWoD group [(7.3±1.2) mm] than that in DDWR group [(6.5±1.3) mm] and that in DDWoR group [(6.1±1.4) mm] (P<0.05). The inter-condyle angle presented significantly larger in biND group (136°±13°) and uniDD group (132°±14°) than that inbiDD group (124°±17°) (P<0.05). Conclusions: The mandibular condylar morphology changes significantly presented in the patients with temporomandibular disc displacement for the temporomandibular disorders.

[Peripheral small airway dysfunction differences between idiopathic pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension]

Objective: To investigate the peripheral small airway dysfunction differences between idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Methods: Impulse oscillmetory system testing (IOS) and pulmonary function testing (PFT) were performed in IPAH and CTEPH patients and 30 healthy control group. We also carried out a subgroup analysis depending on their medical history of airway diseases. Results: We included 42 IPAH and 47 CTEPH patients (with or without airways disease: 8 vs. 34 and 17 vs. 34, respectively). Compared with CTEPH patients, IPAH patients were younger but had more serious pulmonary vessel resistance and mean pulmonary arterial resistance. Compared with IPAH patients, CTEPH patients had significant impaired peripheral small airway dysfunction with decreased of MEF(50) (% pred), MMEF(75/25) evaluated by PFT and R5-R20, Δ R5-R20 and AX measured by IOS [10.6(2.0, 33.0) vs. 2.5(-5.0, 16.5); 22.1(14.0, 32.6) vs. 15.5 (7.0, 23.2); 7.64(4, 18.6) vs. 6(3, 11) respectively, all P<0.05]. Subgroup analysis revealed there were no significant peripheral small dysfunction differences in IPAH patients with or without airway diseases. CTEPH patients had a higher proportion of airway diseases and more serious peripheral dysfunction than IPAH patients with airway diseases. Compared with control healthy group, peripheral airway dysfunction was more obvious even in IPAH and CTEPH patients without airway diseases. Conclusion: Compared with IPAH, CTEPH patients were older, but had better hemodynamics and a higher proportion of airway diseases. The peripheral airway dysfunction were more serious in CTEPH patients without airway diseases than IPAH patients without airway diseases and healthy controls group.

Active tuning of directional scattering by combining magneto-optical effects and multipolar interferences

An efficient route is proposed to actively manipulate directional scattering based on magneto-optical (MO) effects and multipolar interferences with a coated MO cylinder. We demonstrate that the presence of an external magnetic field B contributes to breaking the degeneracy of multipoles and making them rotate. The rotated modes further interfere with each other, thus reshaping scattering profiles and introducing novel directional optical switching (OS) phenomena. As a result, we show that forward scattering (FS) and backward scattering (BS) can be flexibly altered by turning on or off the B for both s-polarization and p-polarization, and optical switching exhibits broadband performance as well. More specifically, the proposed nanostructure also operates robust and reliable functionalities when considering realistic MO materials with optical loss and dispersion; therefore, they are ideal candidates to develop reconfigurable, tunable and versatile optical devices.

Polarization management based on dipolar interferences and lattice couplings

We have achieved efficient polarization manipulations based on dipolar interferences and lattice couplings in one-dimensional cylindrical metalattices. First, we employ the scattering asymmetry factor g to quantify the directional scattering ability and find the maximum |g|_max=1/2 for a cylinder with effective excitations of electric and magnetic dipoles simultaneously. Further, the strong negative-g (gp = -0.38) for p-polarization and positive-g (gs = 0.68) for s-polarization are obtained within a narrow visible band using c-Si with experimental data. Inspired by the polarization-dependent phenomena, we design a metalattice-based linear polarizer considering lattice effects with an optimal particle arrangement. The metalattice performs near-perfect reflection for p-polarized waves but with zero reflection for s-polarized waves with large extinction ratios for transmission (17 dB) and reflection (24 dB). The perfect functionalities can be attributed to the near-field lattice couplings with dipolar interferences. And, we reveal that the polarization-dependent scattering coefficients, which are sensitive to the lattice period, can be largely tuned owing to lattice effects, therefore contributing to modifying far-field scattering patterns. More specifically, the proposed linear polarizers also show robust and reliable functionalities when considering lattice imperfections, the effects of system sizes, oblique incident angles, and the tunbility for different working wavelengths. The present study paves a way to stimulate many advanced practical implements based on multipolar interferences and lattice couplings.

[Preliminary study on the accuracy of infrabony root surface area of single-root teeth by periapical films]

OBJECTIVE

To explore the accuracy of periapical film in evaluating the infrabone root surface area of single-root teeth with different types of resorption of the alveolar bone.

METHODS

In this study, the medical records and imaging data of patients in Department of Periodontology of Peking University Hospital of Stomatology from January 2014 to December 2016 were retrospectively analysed. The involved teeth were divided into two groups: horizontal bone loss group and vertical bone loss group. Digital three-dimensional models of teeth were segmented from cone beam computed tomography (CBCT) data, and the percentage of the infrabone root surface area was measured. While the percentage of the residual alveolar bone was measured on the periapical films. The correlation of the two percentages were analyzed, and the differences between the two percentages of each group were compared.

RESULTS

Thirty-two patients and 79 single-root teeth were involved totally, in whom there were 25 men and 7 women, aged 26-60 years, and of which there were 41 teeth in the horizontal bone loss group and 38 teeth in the vertical bone loss group. The remaining alveolar bone height percentages were 45.13%-90.39% on the periapical films, and at the same time, the infrabone root surface area percentages were 36.27%-93.03% on CBCT. The residual alveolar bone height percentage of the horizontal bone loss group was not subject to normal distribution, so the residual alveolar bone height percentage and the infrabone root surface area percentage were analyzed by Wilcoxon matched pair rank test (P=0.382), and the result showed no statistically significant difference. The mean value of difference value of the two measurements was 0, and the consistency limit of 95 % was -9.7%-9.8%, between the clinical consistency limit (-15%-15%).The residual alveolar bone height percentage and the infrabone root surface area percentage of the vertical bone loss group were analyzed by paired T test (P< 0.001), and the result showed statistically significant difference. The mean value of difference value of the two measurements was 7.2 %, and the consistency limit of 95% was -13.1%-27.5%, beyond clinical consistency limit (-15%-15%).

CONCLUSION

For the teeth with horizontal bone loss, the proximal residual alveo-lar bone height reflected on the periapical films could show the infrabone root surface area relatively accurately. For the teeth with vertical bone loss, the periapical films could not show the degree of periodontal tissue loss accurately, and it would underestimate the extent of bone destruction usually, so CBCT might be taken to show the bone destruction condition of this type of teeth if necessary.

[The images of osteoarthrosis associated with anterior disc displacement without reduction detected by cone-beam CT]

Objective: To analyze the radiological characteristics of the condylar bone in patients with anterior disc displacement without reduction of temporomandibular joint using cone-beam CT (CBCT), and to further investigate the clinical factors possibly associated with the early-stage osteoarthritic changes. Methods: Two hundred and four individuals (≤30 years old) diagnosed as unilateral anterior disc displacement without reduction (disease duration≤1 year) were recruited. CBCT images of bilateral condyles were independently evaluated by two assessors and documented. Correlation between the early-stage osteoarthritic (OA) changes and gender, age, disease duration and mouth opening were analyzed using SPSS 21.0 software. Results: About sixty percent were presented with OA changes in the symptomatic joints, and most of them (47.1%) (96/204) were early-stage OA changes characterized by loss of continuity of articular cortex (Ⅰ) and/or surface erosion (Ⅱ). Logistics regression analyses indicated that disease duration (P =0.000) and mouth opening (P =0.002) were correlated significantly with early-stage OA changes. Conclusions: Disc displacement without reduction was closely related to OA occurrence. OA changes occurred in more than half of the patients after one month of the joint locked and more possibly in patients with increased mouth opening.

[Evolution and quality evaluation of Gardenia jasminoides(Zhizi) of successive ages]

In addition to its frequently-used antipyretic function, Gardenia jasminoides is also used in food or industrial dyeing. In ancient times, herbalists believed that the quality of Gardenia jasminoides for medical use was different from that for dye due to its different germplasm. Since the 1912, Gardenia jasminoides for dye was named "Shui(watery) Zhizi" in order to distinguish it from "Shan (hilly) Zhizi" . Henan was the earliest producing area for Gardenia jasminoides in ancient times, then after the Ming Dynasty, the producing area migrated to the Southern regions, including Jiangxi and Fujian Provinces. Nowadays, both provinces are the main producing area. The ancient herbal books paid great attention to the quality evaluation of officinal Gardenia jasminoides, which was mainly based on its appearance and the quality differences between wild and cultivated varieties. Since modern times, Gardenia jasminoides has been divided into different commodity specification levels according to the producing area, external properties and other elements, and its external properties are consistent with the ancient records. The germplasm, producing area, harvest and quality evaluation of Gardenia jasminoides in the herbal books of successive ages are sorted out, and the division elements of its commercial specification levels analyzed since modern times, thus providing a basis for present study on the commodity specification levels and the grading of the commercial specificity of Gardenia jasminoides.

[Disturbed sleep, anxiety and stress are possible risk indicators for temporomandibular disorders with myofascialpain]

OBJECTIVE

To explore the relationship betweensleep/psychological distress and temporomandibular disorders (TMD) and to discuss the possibility of disturbed sleep and psychological distress as risk indicators in relation to TMD in a Chinese population.

METHODS

The standardized and validated self-reported Chinese version questionnaires including Pittsburgh sleep quality index (PSQI) and depression, anxietyandstress scales-21 (DASS-21) were used to measure sleep quality and psychological distress. A total of 755 TMD patients (172 males and 583 females)with a mean age (29.99 ± 13.60) years were included in the study. The patients were divided into 7 diagnostic groups based on the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), including Group I(exclusively myofascial pain), Group II(exclusively disc displacement), Group III (exclusively arthralgia or degenerative joint disease), Group IV (myofascial pain plus disc displacement), Group V (myofascial pain plus arthralgia or degenerative joint disease), Group VI (disc displacement plus arthralgia or degenerative joint disease) and Group VII (myofascial pain plus disc displacement plus arthralgia or degenerative joint disease). For statistical analysis, the patients were subsequently grouped into those with (181 patients) and without (574 patients) myofascial pain. Chi-square tests, independent-samples t test, partial correlation as well as stepwise Logistic regression analysis were used to analyze the data, using software SPSS 20.0 and P<0.05 was of significance.

RESULTS

The prevalence of moderate to (extremely) severe disturbed sleep and psychological distress was significantly higher in the myofascial pain group (27.1%, 28.7%, 60.8% and 32.0%) than in the non-myofascial pain group (disc displacement and arthralgia or degenerative joint disease, 11.1%, 10.1%, 27.4% and 11.0%, P<0.05).The comorbidity of self-reported disturbed sleep and psychological distress was significantly higher in the myofascial pain patients than those without myofascial pain (P<0.05). Stepwise logistic regression analysis demonstrated that disturbed sleep (OR=1.74), more specifically, subjective sleep quality (OR=1.69) and sleep disturbance (OR=1.63) respectively, anxiety (OR=3.14) and stress (OR=2.15) were possible risk indicators for myofascial pain, and the results were still significant even after controlling for age, sex, educational level, disease duration, sleep quality, depression, anxiety and stress respectively (P<0.05).

CONCLUSION

Disturbed sleep and psychological distress symptoms are common in TMD patients. Disturbed sleep, anxiety and stress are possible risk indicators for myofascial pain, compared with disc displacement and arthralgia or degenerative joint diseases.

[Disturbed sleep, anxiety and stress are possible risk indicators for temporomandibular disorders with myofascialpain]

OBJECTIVE

To explore the relationship betweensleep/psychological distress and temporomandibular disorders (TMD) and to discuss the possibility of disturbed sleep and psychological distress as risk indicators in relation to TMD in a Chinese population.

METHODS

The standardized and validated self-reported Chinese version questionnaires including Pittsburgh sleep quality index (PSQI) and depression, anxietyandstress scales-21 (DASS-21) were used to measure sleep quality and psychological distress. A total of 755 TMD patients (172 males and 583 females)with a mean age (29.99 ± 13.60) years were included in the study. The patients were divided into 7 diagnostic groups based on the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), including Group I(exclusively myofascial pain), Group II(exclusively disc displacement), Group III (exclusively arthralgia or degenerative joint disease), Group IV (myofascial pain plus disc displacement), Group V (myofascial pain plus arthralgia or degenerative joint disease), Group VI (disc displacement plus arthralgia or degenerative joint disease) and Group VII (myofascial pain plus disc displacement plus arthralgia or degenerative joint disease). For statistical analysis, the patients were subsequently grouped into those with (181 patients) and without (574 patients) myofascial pain. Chi-square tests, independent-samples t test, partial correlation as well as stepwise Logistic regression analysis were used to analyze the data, using software SPSS 20.0 and P<0.05 was of significance.

RESULTS

The prevalence of moderate to (extremely) severe disturbed sleep and psychological distress was significantly higher in the myofascial pain group (27.1%, 28.7%, 60.8% and 32.0%) than in the non-myofascial pain group (disc displacement and arthralgia or degenerative joint disease, 11.1%, 10.1%, 27.4% and 11.0%, P<0.05).The comorbidity of self-reported disturbed sleep and psychological distress was significantly higher in the myofascial pain patients than those without myofascial pain (P<0.05). Stepwise logistic regression analysis demonstrated that disturbed sleep (OR=1.74), more specifically, subjective sleep quality (OR=1.69) and sleep disturbance (OR=1.63) respectively, anxiety (OR=3.14) and stress (OR=2.15) were possible risk indicators for myofascial pain, and the results were still significant even after controlling for age, sex, educational level, disease duration, sleep quality, depression, anxiety and stress respectively (P<0.05).

CONCLUSION

Disturbed sleep and psychological distress symptoms are common in TMD patients. Disturbed sleep, anxiety and stress are possible risk indicators for myofascial pain, compared with disc displacement and arthralgia or degenerative joint diseases.

Study on the correlation between extracellular matrix protein-1 and the growth, metastasis and angiogenesis of laryngeal carcinoma

OBJECTIVE

To investigate the correlation between extracellular matrix protein-1 (ECM1) and the growth, metastasis and angiogenesis of laryngeal carcinoma.

MATERIALS AND METHODS

Forty-five samples with laryngeal benign and malignant tumors confirmed by pathology in Laiwu City People's Hospital from March 2006 to March 2011 were collected, in which there were 29 cases with laryngeal carcinoma and 16 with benign tumors. The expression of ECM1 and factor VIII-related antigens in patients with laryngeal carcinoma and those with benign tumors was respectively detected using immunohistochemical method, and the correlation between ECM1 staining grade and microvessel density (MVD) was analyzed.

RESULTS

In laryngeal carcinoma tissue, ECM1 was mainly expressed in cytoplasm, less in cytomembrane or intercellular substance. With abundant expression in the tissue of laryngeal benign tumors (benign mesenchymoma and hemangioma), ECM1 was primarily expressed in the connective tissue, which was different from the expression in laryngeal carcinoma tissue. The proportion of positive ECM1 staining (++) in patients with laryngeal carcinoma was dramatically higher than those with benign tumors (p<0.05), and that of strongly-positive ECM1 staining (+++) slightly higher. The results of Spearman nonparametric correlation analysis revealed that ECM1 staining grade in laryngeal carcinoma tissue had a significantly-positive correlation with MVD (r=0.866, p=0.000).

CONCLUSIONS

ECM1 expression in laryngeal carcinoma is closely associated with tumor cell growth, metastasis and angiogenesis, which can be considered as an effective predictor in the occurrence and postoperative recurrence of laryngeal carcinoma.

Isolation and analysis of α-expansin genes in the tree Anthocephalus chinensis (Rubiaceae)

Expansins are cell wall-associated proteins that induce wall extension and relax stress by disrupting noncovalent bonds between cellulose microfibrils and cross-linking glycan chains, thereby promoting wall creep. Anthocephalus chinensis is a very fast-growing economically important tree found mainly in South Asia. Sixteen cDNAs, designated AcEXPA1 to AcEXPA16 (GenBank accession Nos. FJ417847, JF922686-JF922700) with corresponding genomic DNA sequences (GenBank accession Nos. GQ228823, JF922701-JF922715), were isolated by amplifying conserved domain binding with genomic walking and RACE techniques from four differential growth tissues in A. chinensis. These α-expansin homologues were highly conserved in size and sequence; they had the same sequence structures as an N-terminal signal peptide, three exons and two introns. Their amino acid alignment showed that A. chinensis expansin genes are divided into three subgroups: A, B and C. This study is the first report on expansin genes from A. chinensis. It will be used for a tissue-specific expression model and for studying the relationship between expansin genes, growth rate and wood quality of the xylem in this fast-growing tree.

A cascade of anoxic and oxic fluidized bed biofilm reactors for treatment of synthetic municipal wastewater

In this study, a cascade of anoxic and oxic fluidized bed biofilm reactors system was carried out to treat synthetic municipal wastewater. The parameters of the influent flow rates and C/N ratios were discussed. System performance was acceptable for chemical oxygen demand (COD), ammonia, and total nitrogen removal. A decrease of ammonia and total nitrogen removal efficiencies, however, was observed when the influent flow rates increased to 5.04 and 6.12 1 h(-1). Total nitrogen removal decreased at the influent C/N ratio of 3:1. The measured ratios of COD reduction in the anoxic column to nitrogen removal through nitrification-denitrification were 3.7, 3.5, 3.3, and 3.1 g COD/g(-1) N on average when the influent C/N ratios changed from 6:1 to 3:1. The observed sludge yield (Yobs) was 0.169 g VSS g COD(-1) because of perfect denitrification in the anoxic column and the relatively long solids retention time.

A peptide of foot-and-mouth disease virus serotype Asia1 generating a neutralizing antibody response, and an immunostimulatory peptide

The epitopes of the capsid of foot-and-mouth disease virus (FMDV) play important roles in the construction of highly immunogenic subunit vaccines. However few epitopes have been found for FMDV serotype Asia1. In this study we screened for epitopes of the VP1 and VP2 proteins of FMDV serotype Asia1 isolate, YNBS/58. Fragments consisting of amino acids 133-163 of VP1 and amino acids 1-33 of VP2 contained epitopes, and both induced lymphoproliferation in guinea pigs. Only the VP1 fragment induced neutralizing antibodies but the VP2 peptide dramatically increased the neutralizing antibody response induced by the VP1 peptide.

[Expression and significance of PTEN/PI3K signal transduction-related proteins in non-small cell lung cancer]

BACKGROUND & OBJECTIVE

PTEN/PI3K signal transduction pathway regulates cell proliferation and survival, and is closely associated with the development and progress of various tumors. However, the relationship between the function of this pathway with lung carcinoma has not been completely elucidated. This study was to investigate the expression and clinical significance of PTEN/PI3K signal transduction-related proteins, such as insulin-like growth factor-1 receptor (IGF-1R), PTEN and phosphatidylinositol 3-kinase (PI3K), in non-small cell lung carcinoma (NSCLC).

METHODS

The expression of IGF-1R, PTEN, and PI3K in 59 specimens of primary NSCLC, 19 specimens of metastatic lymph nodes, 16 specimens of para-cancerous hyperplastic lung tissues, and 7 specimens of normal lung tissues were detected by SP immunohistochemistry. The difference of positive rates of IGF-1R,PTEN and PI3K was evaluated by Chi-square test and Fisher's exact test.

RESULTS

The positive rates of IGF-1R, PTEN, and PI3K in NSCLC were 72.88%, 27.12%, and 84.75%, respectively. The positive rates of IGF-1R and PI3K were not associated with the clinicopathologic features of NSCLC (P>0.05). The positive rate of PTEN was highly associated with lymph node metastasis of NSCLC (P=0.009), but was not associated with pathologic type and differentiation grade of NSCLC (P>0.05). The positive rate of PTEN was significantly lower and that of PI3K was significantly higher in NSCLC and metastatic lymph node tissues than in para-cancerous hyperplastic and normal lung tissues (P<0.05). The expression of IGF-1R in NSCLC was positively correlated to that of PI3K (r=0.432, P=0.001); while the expression of PTEN was negatively correlated to that of PI3K (r=0.505, P<0.001).

CONCLUSION

Overexpression of IGF-1R and PI3K, and low expression of PTEN are closely correlated to the development, invasion and metastasis of NSCLC.

[Expression and mutation of Fas-associated death domain (FADD) gene in non-small cell lung cancer]

BACKGROUND & OBJECTIVE

Abnormal expression of Fas-associated death domain (FADD) protein, an important adapter in cell apoptosis signal conduction, may closely relate with tumorigenesis. This study was to detect expression and mutation of FADD gene in non-small cell lung cancer (NSCLC), evaluate its effect on development of NSCLC, and explore the mechanism.

METHODS

Polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) was used to detect FADD gene mutation in 62 specimens of NSCLC tissues and 13 specimens of adjacent non-cancerous lung tissues. Immunohistochemistry was used to detect its protein expression. In situ hybridization (ISH) was used to detect FADD mRNA expression in 30 of the 62 specimens of NSCLC tissues. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick labeling (TUNEL) was used to detect apoptotic cells in NSCLC tissues.

RESULTS

Of the 62 specimens of NSCLC tissues, 4 cases of stage N2 showed FADD gene mutation. Positive rate of FADD protein in NSCLC tissues was 80.6% (50/62), its protein level positively correlated with differentiation of NSCLC (rs=0.411, P<0.01). Protein level of FADD in NSCLC tissue was significantly higher than that in non-cancerous tissue (P<0.05). Positive rate of FADD mRNA in NSCLC tissue was 80.0%, its concordant rate with positive rate of FADD protein was 88.6% (P>0.05). Apoptotic cells were observed in all specimens of NSCLC, apoptosis indexes of the 4 cases with FADD gene mutation were lower than the mean level, although they showed positive expression of FADD protein. Protein level of FADD was positively related with cell apoptosis of NSCLC (rs=0.599, P<0.001).

CONCLUSIONS

FADD gene mutation exists in NSCLC, its mutation and abnormal expression might play a crucial role in carcinogenesis of NSCLC. Protein level of FADD closely correlates with cell apoptosis of NSCLC.

Recombinant bivalent vaccine against foot-and-mouth disease virus serotype O/A infection in guinea pig

In this study, two DNA fragments encoding amino acid (141-160)-(21-140)-(141-160) of the VP1 of FMDV (foot-and-mouth disease virus) serotype O and (138-160)-(21-40)-(138-160) of the serotype A FMDV were chemically synthesized. These two tandem-repeat fragments were ligated and transfected into prokaryotic expression vector pTrcHis A to construct pTH-O-A. The other vector called pTH-O-scIgG-A was constructed similarly only that the two tandem-repeat DNA fragments were linked by the bovine-IgG heavy chain coding sequence. Guinea pigs immunized with the two bivalent vaccines pTH-O-A and pTH-O-scIgG-A showed both specific antibody activity and T cell proliferation responses. FMDV challenge tests showed that 85% and 70% of guinea pigs vaccinated twice with 200 mg of the fusion protein of pTH-O-A were protected from FMDV serotype O and serotype A infection respectively. 70% and 57% of the guinea pigs immunized with the fusion protein of pTH-O-scIgG-A were protected from FMDV serotype O and serotype A infection respectively.

[Expression of P53, P63, and C-erbB-2 in endometrioid adenocarcinoma and their clinicopathological significance]

BACKGROUND & OBJECTIVE

Tumor suppressor gene p53 and oncogene C-erbB-2 are confirmed to have close relation with endometrioid adenocarcinoma (EC), few documents have been reported about their correlation. Its structural homology to p53, p63 has been considered as a tumor suppressor gene acompany with p53 mutation, but its suppressive nature has not been confirmed yet; reports about p63 expression in EC are rare. This study was designed to investigate the roles of p53, p63, and C-erbB2 in tumorigenesis and development of EC, and their correlation with clinicopathological features of EC.

METHODS

Immunohistochemical technique was used to detect P53, P63, and C-erbB2 protein expression in 38 cases of EC, 23 cases of endometrial hyperplasia (EH), and 10 cases of benign proliferative endometrium (BPE).

RESULTS

(1) The positive rate of P53 in EC was 31.6%,significantly higher than those in EH and BPE (P < 0.05). P53 expression was associated with surgical pathologic stage, and depth of myometrial invasion in EC (P< 0.005), but was not associated with histological grade (P >0.05). (2) The positive rate of P63 in EC was 81.6%, significantly higher than those in EH and BPE (P < 0.005). P63 expression was not associated with histological grade, surgical pathologic stage, and depth of myometrial invasion in EC (P >0.05). (3) The positive rate of C-erbB-2 in EC was 23.2%, there was no significant difference compared with those in EH or BPE (P >0.05).C-erbB-2 expression was associated with surgical pathologic stage, and depth of myometrial invasion in EC (P< 0.001,P< 0.005),but was not associated with histological grade (P >0.05).(4) There was significantly positive correlation between P53 and P63 (r =0.443,P < 0.01)or C-erbB-2 (r =0.490,P < 0.005).

CONCLUSIONS

Both p53 and p63 are involved in carcinogenesis of EC; p63 may act as an oncogene in tumorigenesis of EC. The expression of P53 and C-erbB2 are related to the progression of malignant EC; P53 and C-erbB-2 co-expression may predict poor prognosis.

[Expression and pathobiological implication of hypoxia-inducible factor-1alpha in human colorectal carcinoma]

OBJECTIVE

To investigate the transcription level and protein expression of HIF-1alpha and VEGF in SW480 cell line and colorectal adenocarcinoma, and to determine whether HIF-1alpha plays a role in angiogenesis through its regulation of VEGF.

METHODS

HIF-1alpha mRNA expression was analyzed by in situ hybridization. HIF-1alpha and VEGF protein expressions were determined by immunochemical streptavidin/peroxidase (SP) in SW480 cells and colorectal carcinoma tissue samples and Western blot, using proteins extracted from SW480 cells. Tumor tissue microvessel density (MVD) was determined by CD34 immunostaining of colorectal carcinomas.

RESULTS

The levels of HIF-1alpha mRNA changed significantly in response to different oxygen concentrations and an addition of genistein in SW480 cells. Immunocytochemistry revealed that the levels of HIF-1alpha, VEGF protein expression in SW480 cells were significantly higher under hypoxia than those in nomoxia (P < 0.01, P < 0.05 respectively). However, addition of genistein, an inhibitor of HIF-1alpha, suppressed such responses to hypoxia. Western blot analysis showed that SW480 cells exposed to hypoxia expressed a high level of HIF-1alpha protein, compared to a weak expression in nomoxia. The addition of genistein in hypoxia suppressed the over-expression of HIF-1alpha. The positive rates of HIF-1alpha mRNA by in situ hybridization in colorectal adenomas and adenocarcinomas were 38.9% (7/18) and 67.7% (42/62), respectively. The percentage of HIF-1alpha mRNA positive cells varied significantly from colorectal adenomas to adenocarcinomas at different Duke stages (P < 0.05), and HIF-1alpha mRNA was higher in adenocarcinomas than in adenomas (P < 0.01). The positive rates of HIF-1alpha and VEGF protein expression in adenocarcinomas were 43.5% (27/62) and 37.1% (23/62), respectively. The expression of VEGF elevated as the Duke tumor staging increased. The conformation rate of HIF-1alpha and VEGF was 74.2% (46/62). MVD was significantly higher in HIF-1alpha and/or VEGF positive tumors than those without (P < 0.01 and P < 0.05 respectively). Among the four groups, i.e. HIF-1alpha+/VEGF+, HIF-1alpha+/VEGF-, HIF-1alpha+/VEGF- and HIF-1alpha-/VEGF-, the difference of MVD was highly significant (P < 0.01). HIF-1alpha expression was correlated significantly with VEGF expression and microvessel density.

CONCLUSIONS

These findings suggest hypoxia induces the expression of HIF-1alpha and VEGF in colorectal adenocarcinoma. HIF-1alpha may play an important role in angiogenesis and tumor progression by regulating the expression of VEGF in human colorectal carcinoma.

[Relationship between hMSH2 and FHIT gene expression in non-small cell lung cancer]

BACKGROUND & OBJECTIVE

Abnormality of FHIT gene has been proved to be frequent in certain malignant tumors closely related to environmental oncogenic factors, such as lung cancer. Foreign scholars have begun to explore the relationship between FHIT gene and other tumor suppressor genes, which are implicated in the pathogenesis of lung cancer. This study was designed to investigate the relationship between hMSH(2) and FHIT protein expression and to explore the correlation of hMSH(2) and FHIT protein expression with clinicopathologic features of lung cancer.

METHODS

Immunohistochemical analysis of hMSH(2) and FHIT protein expression in 40 lung cancer cases and 15 adjacent non-cancer lung tissues was performed; the positive rates of FHIT and hMSH(2) proteins were measured by image analysis system.

RESULTS

(1)The positive rates of FHIT and hMSH(2) proteins were 58.2% and 45.8% respectively in lung cancer tissues compared with 89.1% and 65.3% in non-cancer lung tissues. The expression levels of FHIT and hMSH(2) proteins were significantly lower in lung cancer tissues than that in non-cancer lung tissues (P< 0.01). (2)Reduced expression levels of both proteins were significantly related to tumor histology. The positive rate of the FHIT protein was 52.2% in squamous cell carcinoma compared with 63.4% in adenocarcinomas(P< 0.01), whereas the positive rate of the hMSH(2) protein was 35.6% in adenocarcinomas compared with 53.2% in squamous cell carcinoma(P< 0.01). (3)A correlation between FHIT reduced expression and lymph node metastasis was observed(P< 0.01). The positive rate of the FHIT protein was 54.1% in lung cancer tissues with metastasis compared with 60.5% in lung cancer tissues without metastasis. No association was found between hMSH(2) reduced expression and nodal metastasis(P >0.05). (4)Loss of FHIT protein correlated significantly with lasting and heavy smoking(P< 0.01). The positive rate of the FHIT protein was 53.1% in smoking group compared with 66.1% in non-smoking group. The reduction of hMSH(2) expression was not associated with smoking(P >0.05). (5)An inverse correlation was found between hMSH(2) reduced expression and FHIT protein loss (P< 0.01, RR=-0.54).

CONCLUSION

FHIT gene may be a negative regulatory gene of hMSH(2) gene, and play an important role in the inactivation mechanism of hMSH(2) gene.

[Expression of apoptosis and proliferation related genes in carcinogenesis of lung squamous cell carcinoma in rats]

BACKGROUND & OBJECTIVE

The activation of caspase-3 protein, located the downstream of apoptosis, is the key of cell apoptosis signal conduction. Caspase-3 is the most important performer in accelerating apoptosis in the caspase family. Much progress has been achieved in the study of caspase-3 and human non-small cell lung cancer. This study was designed to investigate the effect of cellular proliferation and apoptosis related genes caspase-3 and proliferating cell nuclear antigen (PCNA), and to seek whether they could be chosen as molecular biology markers for lung cancer.

METHODS

3-Methylcholanthrene (MCA) and diethyinitrosamine (DEN) were used to induce lung squamous cell carcinoma by intra-left lobar-bronchial instillation in 50 Wistar rats. The other 10 rats instilled with iodized oil were regarded as control group. The expression of caspase-3 and PCNA were evaluated by SP immunohistochemistry during carcinogenesis. TUNEL(TDT-mediated dUTP nick end labeling) method was used to examine apoptotic cells.

RESULTS

For the rat bronchial epithelium cells in control group, precancerous lesions, and lung squamous cell carcinoma, positive coefficient values of caspase-3 protein were 3.10+/-0.99, 2.25+/-1.13, and 1.38+/-0.95 on average, respectively; the means of PCNA-labeling index (PCNA-LI)were 14.10+/-5.02, 28.13+/-8.72, and 41.88+/-14.24, respectively; the means of apoptotic index(AI) were 0.60+/-0.52, 2.06+/-0.85, and 2.26+/-1.14, respectively.Significant differences in caspase-3 protein expression were observed between bronchial epithelium in control group and lung squamous cell carcinoma (P< 0.01). Caspase-3 expression was showed stronger in precancerous lesions than that in lung cancer (P< 0.05). Low proliferation index and low AI were detected in rat bronchial epithelium region in control group,which were significant differences in precancerous lesions and lung cancer, respectively (P< 0.01). In 34 rats with lung squamous cell carcinoma, there was negative relationship between caspase-3 and PCNA-LI (r=-0.7306, P< 0.01), so did it in AI and PCNA-LI(r=-0.8127,P< 0.01), but there was no relationship between caspase-3 expression and AI(P >0.05).

CONCLUSION

Loss of caspase-3 expression may be associated with the development of lung squamous cell carcinoma in Wistar rats, but it is not associated with AI. PCNA-LI is an important marker for malignant progression of lung cancer.

[High-level production of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) by feb-batch culture of Alcaligenes eutrophus]

Fermentation strategies for production P (3HB-co-3HV) from glucose and propionic (or valeric) acid by Alcaligenes eutrophus were studied. During the culture, we controlled pH of the broth by feeding precusors of 3HV- propionic or valeric acid after Ammonia feeding stopped. When propionic acid were used as the precusor, for 50 hours, we obtained a cell dry weight, a P(3HB-co-3HV) concentration, a P(3HB-co-3HV) content and a 3HV fraction of 149.9 g/L, 124.9 g/L, 83.3% and 12.4 mol%, respectively, with a PHA productivity of 2.50 g h-1 L-1. When valeric acid were used as the precusor, for 45 hours, we obtained a cell dry weight, a P(3HB-co-3HV) concentration, a P(3HB-co-3HV) content and a 3HV fraction of 160.2 g/L, 119.0 g/L, 74.2% and 17.7 mol%, respectively, with a PHA productivity of 2.64 g h-1 L-1. Prior to this study, it hasn't been reported to obtain such high level productivity and 3HV fraction at the same time by Alcaligenes eutrophus.

Selectivity of intramuscular stimulating electrodes in the lower limbs

Intramuscular (IM) electrodes have been used safely and effectively for decades to activate paralyzed muscles in neuroprosthetic systems employing functional electrical stimulation (FES). However, the response to stimulation delivered by these and any type of electrode can be limited by a phenomenon known as spillover, in which the stimulus intended to produce a contraction in a particular muscle inadvertently activates another muscle, causes adverse sensation, or triggers undesired reflexes. The purpose of this retrospective study was to determine the selectivity of monopolar intramuscular stimulating electrodes implanted in the lower limbs of individuals with motor and sensory complete paraplegia secondary to spinal cord injury (SCI) and to catalog the most common electrode spillover patterns. The performance records of 602 electrodes from 10 subjects who participated in a program of standing and walking with FES in our laboratory over the past decade were examined. Sixty percent (358) of these electrodes were "stable" (i.e., stimulated responses were consistent during the first 6 months postimplant), and 32% of all stable electrodes (113) exhibited spillover as noted in clinical and laboratory records. Common spillover patterns for eight muscle groups were tabulated and analyzed in terms of their functional implications. The beneficial (activation of synergistic muscles) or deleterious (activation of compromising reflexes, antagonists, or adverse sensation) effects of spillover were highly context dependent, with several potentially useful spillover patterns in certain phases of gait becoming undesirable and limiting in others. Knowledge of the selectivity of intramuscular electrodes and the patterns of spillover they exhibit should guide surgeons and rehabilitationists installing lower-limb neuroprostheses during the implantation process and allow them to better predict the ultimate functional usefulness of the electrodes they choose.

[Improvement of nitrogen fixation efficiency and plasmid stability in Bradyrhizobium japonicum by the introduction of dctABD and parCBA/DE genes]

A recombinant plasmid pHN207 containing C4-dicarboxylic acid transport genes (dctABD) from Sinorhizobium meliloti, parCBA/DE genes from pTR102 and reporter genes luxAB from pDB30 was constructed by using pLAFR3 as the vector. The pHN207 was then introduced into the Bradyrhizobium japonicum TA11 and CB1809 by bi-parental mating. It was confirmed that parCBA/DE genes could increase the stability of pLAFR3 in the transconjugants under both free-living and symbiotic condition. The results of plant pot experiment indicated that the introduction of dctABD genes could significantly improve the symbiotic nitrogen fixation efficiency of TA11 and CB1809 with soybean varieties of Heilong 33, Ningzhen No. 1 and Yudou No. 1. Compared with the control, the shoot dry weight (biomass) and total nitrogen content of the plants tested were significantly increased.

[Effect of superoxide dismutase and diethyldithiocarbamate on the induction of squamous cell carcinoma of lung with methylcholanthrene in rats]

The squamous cell carcinoma of lung was induced with methylcholanthrene (MCA) in iodized oil in Wistar rats. During the development of the cancer, the animals were given superoxide dismutase (SOD) or its inhibitor diethyldithiocarbamate (DDC). In DDC group, 3 out of 50 rats developed cancer and 4 developed atypical hyperplasia of bronchial epithelium within 35 to 40 days. In SOD group, no cancer developed in all of the 52 rats, and only one had atypical hyperplasia in the lungs. Only one of 42 control rats had cancer and 2 rats had atypical hyperplasia of bronchial epithelium. The difference in cancer frequency between groups DDC and SOD was significant (P < 0.05). The results suggest that there is a synergism between DDC and MAC in the induction of lung cancer, while SOD can inhibit MCA-induced lung cancer development. The mechanism of the effect of SOD and DDC was discussed.

[Irreversible action of the opioid agonist alpha-CAM and its reaction with SH groups at opioid receptor binding sites]

7 alpha-Bis (beta-chloroethyl)amino-methyl-6,14-endoethenotetrahydrooripavine (alpha-CAM) was found to bind to opioid receptors irreversibly and react directly with sulfhydryl (SH) groups in P2 preparations of rat brain. The P2 preparations were pretreated as follows: protection of the SH groups at the opioid receptor binding sites by morphine or etorphine, and inactivation of the SH groups outside the binding sites by N-ethylmaleimide (NEM), followed by removal of the morphine or etorphine by washing. alpha-CAM was still able to bind the pretreated P2 preparations in an irreversible manner. The results indicate that the formation of covalent bonds between alpha-CAM and the SH groups of opioid receptor binding sites is possibly one of the biochemical mechanisms of the irreversible action of alpha-CAM.