Regulation of PGC-1α of the Mitochondrial Energy Metabolism Pathway in the Gills of Indian Medaka (Oryzias dancena) under Hypothermal Stress

Ectothermic fish exposure to hypothermal stress requires adjusting their metabolic molecular machinery, which was investigated using Indian medaka (Oryzias dancena; 10 weeks old, 2.5 ± 0.5 cm) cultured in fresh water (FW) and seawater (SW; 35‱) at room temperature (28 ± 1 °C). The fish were fed twice a day, once in the morning and once in the evening, and the photoperiod was 12 h:12 h light: dark. In this study, we applied two hypothermal treatments to reveal the mechanisms of energy metabolism via pgc-1α regulation in the gills of Indian medaka; cold-stress (18 °C) and cold-tolerance (extreme cold; 15 °C). The branchial ATP content was significantly higher in the cold-stress group, but not in the cold-tolerance group. In FW- and SW-acclimated medaka, the expression of genes related to mitochondrial energy metabolism, including pgc-1α, prc, Nrf2, tfam, and nd5, was analyzed to illustrate differential responses of mitochondrial energy metabolism to cold-stress and cold-tolerance environments. When exposed to cold-stress, the relative mRNA expression of pgc-1α, prc, and Nrf2 increased from 2 h, whereas that of tfam and nd5 increased significantly from 168 h. When exposed to a cold-tolerant environment, prc was significantly upregulated at 2 h post-cooling in the FW and SW groups, and pgc-1α was significantly upregulated at 2 and 12 h post-cooling in the FW group, while tfam and nd5 were downregulated in both FW and SW fish. Hierarchical clustering revealed gene interactions in the cold-stress group, which promoted diverse mitochondrial energy adaptations, causing an increase in ATP production. However, the cold-tolerant group demonstrated limitations in enhancing ATP levels through mitochondrial regulation via the PGC-1α energy metabolism pathway. These findings suggest that ectothermic fish may develop varying degrees of thermal tolerance over time in response to climate change. This study provides insights into the complex ways in which fish adjust their metabolism when exposed to cold stress, contributing to our knowledge of how they adapt.

[Predictive value of serum lactate dehydrogenase on prognosis of patients with paraquat poisoning]

Objective: To investigate the predictive value of serum lactate dehydrogenase (LDH) in the prognosis of patients with paraquat (PQ) poisoning, and to provide evidence for early prognosis assessment. Methods: In February 2022, 50 patients with PQ poisoning who completed serum LDH detection admitted to the Department of Emergency Medicine, the First Affiliated Hospital of Wenzhou Medical University from January 2012 to December 2021 were selected as the observation group, and 50 healthy physical examination personnel were randomly selected as the control group. Patients with PQ poisoning were divided into survival group and death group according to the prognosis, and the differences of blood routine routine, liver and kidney function and other indicators in the first admission between the two groups were compared. Multivariate logisitic regression model was established, ROC curve was drawn, and the influencing factors of prognosis of patients with PQ poisoning were analyzed. Results: Compared with the control group, the white blood cell count (WBC), total bilirubin (TBil), alanine aminotransferase (ALT), aspartate aminotransferase (AST), LDH, glucose (GLU) and creatinine (Cr) in observation group were significantly increased, while albumin (ALB) and total cholesterol (TC) were significantly decreased (P<0.05). Univariate analysis showed that WBC, elevated LDH (>247 U/L), TBil, ALT, AST and Cr were significantly different between PQ poisoning survival group and death group (P<0.05). Multivariate logisitic regression analysis showed that elevated serum LDH was an independent risk factor for the prognosis of PQ poisoning patients (OR=9.95, 95%CI: 1.34-73.82, P=0.025). The area under the ROC curve of LDH was 0.811 (95%CI: 0.692-0.930). When the cut-off value was 340 U/L, the sensitivity was 0.889 and the specificity was 0.719. Log-rank test showed that there was a statistically significant difference in survival rate between the normal LDH group and the elevated LDH group (P=0.001) . Conclusion: Serum LDH has a good predictive value in evaluating the prognosis of patients with PQ poisoning. Elevated LDH is a risk factor for poor prognosis of patients with PQ poisoning.

[Dietetic Materia Medica (Yue Fu Shi Wu Ben Cao) : The rise of Dietetic Materia Medica in the Edo Period in Japan]

Food was believed to have some medicinal properties apart from its everyday sustenance in Japan in the Edo period (1603-1867). The dietetic materia medica then became a knowledge system in Japan with reference of the knowledge system of traditional Chinese materia medica, following some related books published.Dietetic Materia Medica (Yue Fu Shi Wu Ben Cao) was written by Nagoya Genyi as the pioneer work on dietetic materia medica in the Edo period. The book was divided into two volumes. The first one involved a total of 290 types of dietetic materia medica and 167 types of botanical medicines (grains, vegetables, aquatic plants, fungi, fruits, and herbs). The second volume included 123 types of animal medicines (fish,meso, poultry and animal sections). Its author, Nagoya Genyi, was the first doctor to link food with clinical treatment in Japan. He mainly focused on disease treatment in terms of specific classification and exposition. In this sense, the book was characteristic of materia medica rather than its museum properties. The content of the book showed the writing style and the medical tendency of the early food materia medica in the Edo period. Researching this book can help in understanding the compilation of dietetic materia medica represented by physicians in this period in Japan.

[XBP1 modulates hypoxia/reoxygenation injury in mouse renal tubular epithelial cells through TXNIP-NLRP3 signaling pathway]

Objective: To investigate the role and regulation mechanism of X box binding protein 1 (XBP1) for hypoxia/reoxygenation(H/R) injury in mouse renal tubular epithelial cells (TCMK-1) through thioredoxin interacting protein (TXNIP)-nucleotide-binding domain (NOD)-like receptor protein (TXNIP-NLRP3) signaling pathway. Methods: The cells were divided into 4 groups: si-NC group transfected with negative control siRNA (si-NC), si-XBP1 group transfected with siRNA targeting XBP1 (si-XBP1), si-NC+H/R group transfected with si-NC and exposed to H/R, and si-XBP1+H/R group transfected with si-XBP1 and exposed to H/R. The Annexin Ⅴ/PI double-staining method was used to detect cell apoptosis; The mitochondrial membrane potential (MMP) was determined by using JC-1 dye; The mitochondrial reactive oxygen species (mROS) was assessed by using MitoSOX™ dye. The interference efficiency of XBP1 was tested by Western blotting and quantitative real-time polymerase chain reaction. The expression levels of TXNIP, NLRP3 and IL-1β protein were detected by Western blotting. The colocalization of mitochondria and TXNIP was detected by double-labeling immunofluorescent staining. The intergroup difference was compared by using an independent samples t-test. Results: Compared with the si-NC group, more mROS, apoptosis and lower MMP were observed in si-NC+H/R group. Compared with the si-NC+H/R group, less apoptosis (12.08±0.51 vs 19.01±1.80, P<0.05), mROS (34.63±0.64 vs 48.17±1.84, P<0.01) and higher MMP (1.03±0.11 vs 0.45±0.08, P<0.05) were observed in si-XBP1+H/R group. Down-regulation of XBP1U (protein: 1.31±0.18 vs 0.23±0.02, P<0.01; mRNA: 1.12±0.07 vs 0.38±0.01, P<0.001) and XBP1S (protein: 1.13±0.17 vs 0.28±0.07, P<0.01; mRNA: 8.39±0.63 vs 2.45±0.22, P<0.001) inhibited expression of TXNIP (0.15±0.02 vs 0.04±0.01, P<0.01), NLRP3 (1.13±0.12 vs 0.51±0.12, P<0.05) and IL-1β (1.02±0.04 vs 0.19±0.06, P<0.001) during H/R. Meanwhile, TXNIP exhibited significantly much less colocalization with mitochondria in the si-XBP1+H/R group. Conclusion: Supression of XBP1 expression can effectively alleviate H/R-induced TCMK-1 cells injury, whose mechanism may be inhibition of TXNIP-induced NLRP3 inflammasome activation.

[The clinical effect of static staple in the treatment of lateral metatarsal neck fracture]

Objective: To investigate the clinical effect of static staple in the treatment of metatarsal neck fracture. Methods: The clinical data of 34 patients with the 2(nd) to 5(th) metatarsal neck fracture admitted to the Department of Orthopaedic Surgery, Tianjin Fifth Central Hospital from January 2017 to December 2018 were retrospectively analyzed.Seventeen patients were treated with static staple and 17 with retrograde Kirschner wire.In solustaple group, there were 11 males, 6 females, aged 34.6 years (range: 21 to 50 years), 10 cases on the right side, 7 cases on the left side.In retrograde Kirschner wire group, there were 12 males and 5 females, aged 36.2 years (range: 23 to 53 years), 9 on the right and 8 on the left.The fracture healing time was recorded and the postoperative complications were counted.The American Orthopedic Foot and Ankle Society Score (AOFAS) forefoot score, visual analogue scale (VAS), and the active flexion and extension range of metatarsophalangeal joints were measured to compare the clinical efficacy of the two groups.The data were compaired by t test, non-parametric or χ(2) test. Results: All patients were followed up for 14.2 months (range: 12 to 17 months).All the fractures were healed and there was no statistically significant difference between solustaple group and retrograde Kirschner wire group in fracture healing time ((11.2±2.1) week vs.(11.5±3.1) week, t=0.030, P=0.743).There was no statistically significant difference between VAS (1.00 (1.00) vs.1.00 (1.50) M(Q(R)), Z=-0.443, P=0.658) and AOFAS scores(90.9±5.3 vs. 88.6±6.1, t=1.174, P=0.249) at the last follow-up. The difference in active dorsiflexion((35.1±4.3)° vs.(31.2±6.4)°, t=2.055, P=0.048) and flexion range of motion ((34.7±4.5)° vs. (30.2±5.3)°, t=2.681, P=0.011) between the two groups was statistically significant. One case of open fracture in the Solustaple group had local skin necrosis, and three patients had metatarsal pain after weight-bearing walking. Four patients in the retrograde Kirschner wire group developed metatarsalgia after weight-bearing walking, and two patients developed mild dorsal extension contracture and joint pain. Conclusions: The treatment of the 2(nd) to 5(th) metatarsal neck fracture by static staple is minimally invasive and firmly fixed. It can effectively reduce the complications of tendon and joint adhesion, and is beneficial to the fracture healing and joint function recovery.

[A preliminary study of serum marker alpha-enolase in the diagnosis of hepatocellular carcinoma]

Objective: To investigate the diagnostic value of serum α-enolase (ENO1) in the primary hepatocellular carcinoma. Methods: From May 2012 to March 2017, 163 cases with liver diseases who met the inclusion and exclusion criteria were admitted to the Infectious Diseases Department of the General Hospital of Ningxia Medical University. Among them, 28 cases were of chronic hepatitis B (CHB), 31 cases with liver cirrhosis (LC), 104 cases with hepatocellular carcinoma (HCC), and 18 healthy volunteers (NC). Patient data and serum samples were collected and liver disease related indicators were measured to detect ENO1 levels with enzyme-linked immunosorbent assay (ELISA). The measured indicators were expressed in median. Mann-Whitney U nonparametric test was used to analyze the differences between the data. A Spearman's correlation analysis was used for bivariate correlation analysis. The sensitivity and specificity of ENO1 and alpha-fetoprotein in the diagnosis of liver cancer were analyzed by ROC curve. Results: Serum level of ENO1 in CHB group, LC group and HCC group was significantly higher than normal group. Serum level of ENO1 in HCC group was higher than CHB group (P = 0.001) and LC group (P < 0.01). Area under the curve (AUC) for serum ENO1 and alpha-fetoprotein were 0.782 (cut-off value 75.96, P = 0.000 1) and 0.800 (cut-off value 27.02, P = 0.000 1), respectively. There was a positive correlation between ENO1 and AFP (P = 0.001). The combined detection had significantly improved the detection efficiency (AUC = 0.835). Serum ENO1 was statistically significant (P < 0.05) in HCC tumor size (AUC = 0.663), tumor metastasis (AUC = 0.681), TNM stage (AUC = 0.710, stage I vs. II), and Edmondson grade (AUC = 0.685) (P < 0.05) and the elevated levels of ENO1 had significantly reduced (P < 0.05) the survival time. Conclusion: ENO1 can be a new candidate marker for the diagnosis of early stage HCC and its progression.

Cortisol regulation of Na+, K+-ATPase β1 subunit transcription via the pre-receptor 11β-hydroxysteroid dehydrogenase 1-like (11β-Hsd1L) in gills of hypothermal freshwater milkfish, Chanos chanos

Hypothermal stress changes the balance of osmoregulation by affecting Na⁺, K⁺-ATPase (Na-K-ATPase) activity or inducing modulation to epithelium permeability in fish. Meanwhile, cellular concentrations of cortisol can be modulated by the pre-receptor enzymes 11β-hydroxysteroid dehydrogenase 1 and 2 (11β-Hsd1 and 2). In fish, increasing levels of exogenous cortisol stimulate Na⁺ uptake via specific interaction with cortisol. This study investigated cortisol effects on expression of Na-K-ATPase subunit proteins and activity in gills of milkfish under hypothermal stress and revealed that the plasma cortisol contents as well as gill 11β-hsd1l and na-k-atpase β1 mRNA abundance were decreased in fresh water (FW) milkfish. Meanwhile, in the seawater (SW) milkfish, the plasma cortisol contents and gill 11β-hsd1l and na-k-atpase β1 mRNA abundance was increased under hypothermal stress. On the other hand, the abundance of 11β-hsd2 mRNA increased in both FW and SW. In addition, 11β-hsd1l expression increased in FW milkfish but decreased in SW milkfish after cortisol injection. Accordingly, the results that gill Na-K-ATPase activity of FW milkfish was affected by environmental temperatures as well as cortisol-dependent Na-K-ATPase β1-subunit levels might be due to increased expression of 11β-hsd1l that elevated intracellular cortisol contents. In hypothermal SW milkfish, decreasing abundance of Na-K-ATPase β1 protein due to reduced expression of 11β-hsd1l was found after cortisol injection. Thus, under hypothermal stress, 11β-HSD1L in FW milkfish gills was used to modulate cortisol and the following effects on increasing the transcription of Na-K-ATPase β1 protein.

Positive correlation of gene expression between branchial FXYD proteins and Na+/K+-ATPase of euryhaline milkfish in response to hypoosmotic challenges

FXYD proteins are crucial regulators of Na⁺/K⁺-ATPase (NKA), which plays an important role in ion exchange by providing the driving force for other ion-transporting systems in the osmoregulatory organs, including the gills. In milkfish (Chanos chanos), gill NKA has been widely investigated and found to alter its expression (both mRNA and protein) and activity in response to environmental salinity changes. However, the expression and roles of the regulatory proteins of NKA, the FXYD proteins, in milkfish gills upon salinity challenge is not yet clear. Hence, this study illustrated the potential roles of milkfish branchial FXYD proteins in modulating NKA expression via identification and tissue distributions of FXYD proteins, as well as the effects of salinity on expression of gill fxyd and nka mRNA. Six milkfish FXYD proteins (CcFXYD) were identified. In milkfish gill, gill-specific Ccfxyd11 was the predominant member, followed by Ccfxyd9 and Ccfxyd8. Upon hypoosmotic challenges, increases in gill Ccfxyd11, Ccfxyd8, Ccnka α1, and Ccnka β1 mRNA as well as significantly positive correlations were observed. Moreover, after acute salinity changes, expression of gill Ccfxyd11 and Ccnka was found to change with ambient salinity, and significant positive correlations were also exhibited between Ccfxyd11 and Ccnka α1. Overall, these results revealed close relationships between CcFXYD11 and CcNKA α1 in milkfish gills, highlighting the potential roles of CcFXYD11 in osmoregulation.

Shear-band affected zone revealed by magnetic domains in a ferromagnetic metallic glass

Plastic deformation of metallic glasses (MGs) has long been considered to be confined to nanoscale shear bands, but recently an affected zone around the shear band was found. Yet, due to technical limitations, the shear-band affected zone (SBAZ), which is critical for understanding shear banding and design of ductile MGs, has yet to be precisely identified. Here, by using magnetic domains as a probe with sufficiently high sensitivity and spatial resolution, we unveil the structure of SBAZs in detail. We demonstrate that shear banding is accompanied by a micrometer-scale SBAZ with a gradient in the strain field, and multiple shear bands interact through the superimposition of SBAZs. There also exists an ultra-long-range gradual elastic stress field extending hundreds of micrometers away from the shear band. Our findings provide a comprehensive picture on shear banding and are important for elucidating the micro-mechanisms of plastic deformation in glasses.

Metallic glasses deform along nanoscale shear bands, and while it is known that they affect the neighboring glass regions, exactly how is unclear. Here, the authors use magnetic force microscopy to atomically resolve the shear-band affected zone and show its effects extends much further than previously thought.

An assay of optimal cytochrome c oxidase activity in fish gills

Cytochrome c oxidase (COX) catalyzes the terminal oxidation reaction in the electron transport chain (ETC) of aerobic respiratory systems. COX activity is an important indicator for the evaluation of energy production by aerobic respiration in various tissues. On the basis of the respiratory characteristics of muscle, we established an optimal method for the measurement of maximal COX activity. To validate the measurement of cytochrome c absorbance, different ionic buffer concentrations and tissue homogenate protein concentrations were used to investigate COX activity. The results showed that optimal COX activity is achieved when using 50-100 μg fish gill homogenate in conjunction with 75-100 mM potassium phosphate buffer. Furthermore, we compared branchial COX activities among three species of euryhaline teleost (Chanos chanos, Oreochromis mossambicus, and Oryzias dancena) to investigate differences in aerobic respiration of osmoregulatory organs. COX activities in the gills of these three euryhaline species were compared with COX subunit 4 (COX4) protein levels. COX4 protein abundance and COX activity patterns in the three species occurring in environments with various salinities increased when fish encountered salinity challenges. This COX activity assay therefore provides an effective and accurate means of assessing aerobic metabolism in fish.

[Study on anemia and vitamin A and vitamin D nutritional status of Chinese urban pregnant women in 2010-2012]

Objective: To evaluate the prevalence of anemia and the nutritional status of vitamins A and D by analyzing hemoglobin, serum retinol, and serum 25-hydroxyvitamin D levels in Chinese urban pregnant women during 2010-2012. Methods: Data were obtained from the China Nutrition and Health Survey in 2010-2012. Using multi-stage stratified sampling and population proportional stratified random sampling, 2 250 pregnant women from 34 metropolis and 41 middle-sized and small cities were included in this study. Information was collected using a questionnaire survey. The blood hemoglobin concentration was determined using the cyanmethemoglobin method, and anemia was determined using the World Health Organization guidelines combined with the elevation correction standard. The serum retinol level was determined using high-performance liquid chromatography, and vitamin A deficiency (VAD) was judged by the related standard recommended by the World Health Organization. The vitamin D level was determined using enzyme-linked immunosorbent assay and vitamin D deficiency was judged by the recommendation standards from the Institute of Medicine of The National Academies. The hemoglobin, serum retinol, and serum 25-hydroxyvitamin D levels were compared, along with differences in the prevalence of anemia, VAD, and the vitamin D deficiency rate (including deficiency and serious deficiency). Results: A total of 1 738 cases of hemoglobin level, 594 cases of serum retinol level, and 1 027 cases of serum 25-hydroxyvitamin D were available for analysis in this study. The overall blood hemoglobin level (P(50) (P(25)-P(75))) was 122.70 (114.00-131.10) g/L; 123.70 (115.21-132.00) g/L for metropolis and 122.01 (113.30-130.40) g/L for middle-sized and small cities. The blood hemoglobin level of metropolis residents was significantly higher than that of middle-sized and small city residents (P=0.027). The overall prevalence of anemia was 17.0% (295/1 738). The overall serum retinol level (P(50) (P(25)-P(75))) was 1.61 (1.20-2.06) μmol/L; 1.50 (1.04-2.06) μmol/L for metropolis and 1.63 (1.31-2.05) μmol/L for middle-sized and small cities. The serum retinol level of metropolis residents was significantly higher than that of middle-sized and small city residents (P=0.033). The overall prevalence of VAD was 7.4% (47/639); 11.5% (33/286) for metropolis and 4.0% (14/353) for middle-sized and small cities. A significant difference was observed in the prevalence of VAD between metropolis and middle-sized and small city residents (P<0.001). The overall serum 25-hydroxyvitamin D level (P(50) (P(25)-P(75))) was 15.41 (11.79-20.23) ng/ml; 14.71 (11.15-19.07) ng/ml for metropolis and 16.02 (12.65-21.36) ng/ml for middle-sized and small cities. A significant difference was observed in the vitamin D level between metropolis and middle-sized and small city residents (P<0.001). The overall prevalence of vitamin D deficiency was 74.3% (763/1 027); A significant difference was observed in the prevalence of serious vitamin D deficiency between metropolis (30.64%(144/470)) and middle-sized and small city residents (26%(267/1 027))(P=0.002). There were no significant differences between blood hemoglobin level and the prevalence of anemia, VAD, and vitamin D deficiency. Conclusion: The prevalence of anemia in Chinese urban pregnant women improved from 2002 to 2012. The prevalence of vitamin D deficiency in pregnant women was generally more serious, while a certain percentage of women had VAD. The prevalence of VAD and serious vitamin D deficiency among pregnant women from metropolis was significantly higher than that of pregnant women from medium and small-sized cities.

[The vitamin D nutritional status in Chinese urban women of child-bearing age from 2010 to 2012]

Objective: To evaluate the vitamin D nutritional status in Chinese women of child-bearing age by analyzing serum 25-hydroxyvitamin D level in 2010-2012. Methods: Data were obtained from the China Nutrition and Health Survey in 2010-2012. Using cluster sampling and proportional stratified random sampling, 1 514 women of child-bearing age (18-44 years old) from 34 metropolis and 41 small and medium-sized cities were included in this study. Demographic information was collected by questionnaire and serum 25-hydroxyvitamin D concentration was determined by radioimmunoassay, in accordance with the 2010 Institute of Medicine of the National Academies standards. We compared differences in vitamin D levels, specifically serious deficiency, lack of deficiency, insufficiency, and excess. Results: The overall serum 25-hydroxyvitamin D level of Chinese urban women of child-bearing age (P(50) (P(25)-P(75))) was 20.1 (15.1-26.3) ng/ml; minorities had a significantly higher serum 25-hydroxyvitamin D level of 22.0 (15.9-27.5) ng/ml compared with women of Han nationality (19.8 (14.9-26.2) ng/ml) (χ(2)=7.02, P=0.008). The proportions of women with serious deficiency, lack of deficiency, insufficiency, and excess vitamin D were 11.6% (n=175), 37.9% (n=574), 35.1% (n=531), and 0.3% (n=5), respectively. Only 15.1% (n=229) of women of child-bearing age had normal vitamin D nutritional status. No significant differences in vitamin D nutritional status were observed according to age, body mass index, city, nationality, educational level, marital status, or household income per capita (P>0.05). Conclusion: Most Chinese urban women of child-bearing age have poor vitamin D levels and require vitamin D supplementation.

[Study on vitamin A nutritional status of Chinese urban elderly residents in 2010-2012]

Objective: To assess the vitamin A nutritional status of the Chinese urban elderly population by analyzing serum retinol level in 2010-2012. Methods: Data were collected from the Chinese National Nutrition and Health Survey in 2010-2012. Using the multi-stage stratified cluster sampling method, serum samples from elderly residents aged ≥60 years old were obtained from 34 metropolis and 41 middle-sized and small cities. Demographic data were collected using a questionnaire survey. The serum retinol concentration was determined by high-performance liquid chromatography. Vitamin A deficiency (VAD) was determined using the World Health Organization guidelines. A total of 3 200 elderly residents were included in the study. The serum retinol levels and prevalence of VAD and marginal VAD were also compared. Results: The serum retinol concentration (P(50)(P(25)-P(75))) of Chinese urban elderly residents was 1.83 (1.37-2.39) μmoL/L. Compared with middle-sized and small cities (1.91 (1.47-2.48) μmol/L), the retinol level of senior citizens in metropolis (1.70 (1.25-2.25) μmol/L) was significantly lower (P<0.001). The serum retinol levels of elderly male (1.89 (1.37-2.47) μmoL/L) was significantly higher than that of female (1.80 (1.36-2.28) μmoL/L) (P=0.001). The serum retinol concentration was 1.87 (1.42-2.43), 1.78 (1.32-2.33), and 1.71 (1.24-2.24) μmol/L for 60-69, 70-79, and ≥80 years olds, respectively. The retinol level in elderly people ≥70 years olds was significantly lower than that of 60-69 years olds (P<0.001). The overall prevalence of VAD among Chinese urban elderly residents was 4.22% (135/3 200); 6.00% (81/1 350) for metropolis residents and 2.92% (54/1 850) for middle-sized and small city residents. The overall marginal VAD rate of Chinese urban elderly residents was 8.19% (262/3 200); 10.51% (142/1 350) for metropolis residents and 6.49% (120/1 850) for medium-sized and small city residents. The prevalence of VAD and marginal VAD for males was 3.87% (61/1 577) and 8.24% (130/1 577), respectively (P<0.05). The prevalence of VAD according to age group was 3.65% (72/1 975), 4.96% (50/1 008), and 5.99% (13/217), respectively(P=0.097). The prevalence of marginal VAD according to age group was 6.99% (138/1 975), 9.82% (99/1 008), and 11.52% (25/217), respectively(P=0.05). Conclusion: Chinese urban elderly residents showed various levels of VAD, although marginal VAD was quite common. As VAD was more common in metropolis residents and older residents, specific strategies should target these populations.

[The understanding of Epstein-Barr virus associated lymphoproliferative disorder]

In recent years, there are increasing articles concerning Epstein-Barr virus associated lymphoproliferative disorder (EBV+ LPD), and the name of EBV+ LPD is used widely. However, the meaning of EBV+ LPD used is not the same, which triggered confusion of the understanding and obstacles of the communication. In order to solve this problem. Literature was reviewed with combination of our cases to clarify the concept of EBV+ LPD and to expound our understanding about it. In general, it is currently accepted that EBV+ LPD refers to a spectrum of lymphoid tissue diseases with EBV infection, including hyperplasia, borderline lesions, and neoplastic diseases. According to this concept, EBV+ LPD should not include infectious mononucleosis (IM) and severe acute EBV infection (EBV+ hemophagocytic lymphohistiocytosis, fatal IM, fulminant IM, fulminant T-cell LPD), and should not include the explicitly named EBV+ lymphomas (such as extranodal NK/T cell lymphoma, aggressive NK cell leukemia, Burkitt lymphoma, and Hodgkin lymphoma, etc.) either. EBV+ LPD should currently include: (1) EBV+ B cell-LPD: lymphomatoid granulomatosis, EBV + immunodeficiency related LPD, chronic active EBV infection-B cell type, senile EBV+ LPD, etc. (2) EBV+ T/NK cell-LPD: CAEBV-T/NK cell type, hydroa vacciniforme, hypersensitivity of mosquito bite, etc. In addition, EBV+ LPD is classified, based on the disease process, pathological and molecular data, as 3 grades: grade1, hyperplasia (polymorphic lesions with polyclonal cells); grade 2, borderline (polymorphic lesions with clonality); grade 3, neoplasm (monomorphic lesions with clonality). There are overlaps between EBV+ LPD and typical hyperplasia, as well as EBV+ LPD and typical lymphomas. However, the most important tasks are clinical vigilance, early identification of potential severe complications, and treating the patients in a timely manner to avoid serious complications, as well as the active treatment to save lives when the complications happened.

Effect of the Fusarium toxins, zearalenone and deoxynivalenol, on the mouse brain

The aim of this study was to find effects of Fusarium toxins on brain injury in mice. We evaluated the individual and combined effect of the Fusarium toxins zearalenone and deoxynivalenol on the mouse brain. We examined brain weight, protein, antioxidant indicators, and apoptosis. After 3 and 5days of treatment, increased levels of nitric oxide, total nitric oxide synthase, hydroxyl radical scavenging, and malondialdehyde were observed in the treatment groups. This was accompanied by reduced levels of brain protein, superoxide dismutase (apart from the low-dose zearalenone groups), glutathione, glutathione peroxidase activity, and percentage of apoptotic cells. By day 12, most of these indicators had returned to control group levels. The effects of zearalenone and deoxynivalenol were dose-dependent, and were synergistic in combination. Our results suggest that brain function is affected by zearalenone and deoxynivalenol.

The Fusarium toxin zearalenone and deoxynivalenol affect murine splenic antioxidant functions, interferon levels, and T-cell subsets

This study aimed to evaluate the effects of the Fusarium toxin zearalenone (ZEA) and deoxynivalenol (DON) on splenic antioxidant functions, IFN levels, and T-cell subsets in mice. Herein, 360 mice were assigned to nine groups for a 12-day study. Mice were administered an intraperitoneal injection for 4 consecutive days with different concentrations of ZEA alone, DON alone, or ZEA+DON. Spleen and blood samples were collected on days 0, 3, 5, 8, and 12. Mice in each of the experimental groups showed dysreglated splenic antioxidant functions, IFN levels, and T-cell subset frequencies, suggesting that the immune system had been affected. The ZEA+DON-treated groups, especially the group that received a higher concentration of ZEA+DON (Group D2Z2), showed more obvious effects on the dysregulation of splenic antioxidant functions, IFN levels, and T-cell subsets. This finding suggested that DON and ZEA exerted synergistic effects.

Transcriptomic Analysis of Metabolic Pathways in Milkfish That Respond to Salinity and Temperature Changes

Milkfish (Chanos chanos), an important marine aquaculture species in southern Taiwan, show considerable euryhalinity but have low tolerance to sudden drops in water temperatures in winter. Here, we used high throughput next-generation sequencing (NGS) to identify molecular and biological processes involved in the responses to environmental changes. Preliminary tests revealed that seawater (SW)-acclimated milkfish tolerated lower temperatures than the fresh water (FW)-acclimated group. Although FW- and SW-acclimated milkfish have different levels of tolerance for hypothermal stress, to date, the molecular physiological basis of this difference has not been elucidated. Here, we performed a next-generation sequence analysis of mRNAs from four groups of milkfish. We obtained 29669 unigenes with an average length of approximately 1936 base pairs. Gene ontology (GO) analysis was performed after gene annotation. A large number of genes for molecular regulation were identified through a transcriptomic comparison in a KEGG analysis. Basal metabolic pathways involved in hypothermal tolerance, such as glycolysis, fatty acid metabolism, amino acid catabolism and oxidative phosphorylation, were analyzed using PathVisio and Cytoscape software. Our results indicate that in response to hypothermal stress, genes for oxidative phosphorylation, e.g., succinate dehydrogenase, were more highly up-regulated in SW than FW fish. Moreover, SW and FW milkfish used different strategies when exposed to hypothermal stress: SW milkfish up-regulated oxidative phosphorylation and catabolism genes to produce more energy budget, whereas FW milkfish down-regulated genes related to basal metabolism to reduce energy loss.

Fine mapping and characterization of a novel dwarf and narrow-leaf mutant dnl1 in rice

Plant height is one of the most important agronomic traits of rice (Oryza sativa). Dwarf mutants are ideal materials for research on the mechanisms of regulation of rice plant height. We examined a new dwarf and narrow-leaf mutant dnl1. Phenotypic analysis showed that the dnl1 mutant has a thinner culm and more tillers, but the number of grains per panicle, the seed setting rate and the grain weight of dnl1 mutant were found to be significantly lower than in the wild-type. Based on scanning electron microscopic observations, the number of cells in the y-axis in internodes was significantly lower than in the wild-type. In phytohormone induction experiments, dnl1 was gibberellic acid-insensitive. The expression of some genes involved in the gibberellins metabolic pathways was affected in the dnl1 mutant, based on the real-time PCR analysis, suggesting that the dnl1 gene likely plays a role in gibberellin metabolic pathways. Genetic analysis showed that the dwarf and narrow leaf phenotype is controlled by a novel single recessive gene, here referred to as the dwarf and narrow leaf 1 (dnl1), which is located within the region between markers Ind12-11 and RM8214 on the short arm of chromosome 12. By means of fine-mapping strategy, the dnl1 gene was localized within an interval of 285.75 kb physical distance. These results will be useful for dnl1 gene cloning and to improve our understanding of the molecular mechanisms involved in the regulation of growth and development of rice.

A tubular segmented-flow bioreactor for the infection of insect cells with recombinant baculovirus

A continuous process of insect cell (S f9) growth and baculovirus infection is tested with the sequential combination of a CSTR and a tubular reactor. A tubular infection reactor enables continuous introduction of baculovirus and therefore avoids the 'passage effect' observed in two-stage CSTR systems. Moreover, a tubular reactor can be used to test cell infection kinetics and the subsequent metabolism of infected insect cells. Unlike batch and CSTR culture, cells in a horizontally positioned tubular reactor settle due to poor mixing. We have overcome this problem by alternately introducing air bubbles and media and by maintaining a linear velocity sufficient to keep cells suspended. This article addresses the development of the tubular reactor and demonstrates its use as an infection system that complements the two-stage CSTR.

Delayed progressive restenosis of the supraclinoid internal carotid artery treated with percutaneous transluminal angioplasty in a patient with aneurysmal subarachnoid hemorrhage

Typically occurring between 3 days and 3 weeks post-hemorrhage, cerebral vasospasm in the acute stage after aneurysmal subarachnoid hemorrhage is a major contributor to the morbidity and mortality associated with patient outcomes, despite advances in aneurysm treatment and vasospasm management. Though incompletely understood, cerebral vasospasm is well described in the immediate post-hemorrhage patient. Less detailed descriptions exist of delayed or progressive restenosis after aneurysmal subarachnoid hemorrhage and resultant vasospasm. We report a case of delayed progressive supraclinoid internal carotid artery restenosis treated with angioplasty 10 weeks after initial hemorrhage.

A stereotactic method for the three‐dimensional registration of multi‐modality biologic images in animals: NMR, PET, histology, and autoradiography

The objective of this work was to develop and then validate a stereotactic fiduciary marker system for tumor xenografts in rodents which could be used to co-register magnetic resonance imaging (MRI), PET, tissue histology, autoradiography, and measurements from physiologic probes. A Teflon fiduciary template has been designed which allows the precise insertion of small hollow Teflon rods (0.71 mm diameter) into a tumor. These rods can be visualized by MRI and PET as well as by histology and autoradiography on tissue sections. The methodology has been applied and tested on a rigid phantom, on tissue phantom material, and finally on tumor bearing mice. Image registration has been performed between the MRI and PET images for the rigid Teflon phantom and among MRI, digitized microscopy images of tissue histology, and autoradiograms for both tissue phantom and tumor-bearing mice. A registration accuracy, expressed as the average Euclidean distance between the centers of three fiduciary markers among the registered image sets, of 0.2 +/- 0.06 mm was achieved between MRI and microPET image sets of a rigid Teflon phantom. The fiduciary template allows digitized tissue sections to be co-registered with three-dimensional MRI images with an average accuracy of 0.21 and 0.25 mm for the tissue phantoms and tumor xenografts, respectively. Between histology and autoradiograms, it was 0.19 and 0.21 mm for tissue phantoms and tumor xenografts, respectively. The fiduciary marker system provides a coordinate system with which to correlate information from multiple image types, on a voxel-by-voxel basis, with sub-millimeter accuracy--even among imaging modalities with widely disparate spatial resolution and in the absence of identifiable anatomic landmarks.

Decreased efficiency of gamma-ray-induced DNA double-strand break rejoining in malignant transformants of human bronchial epithelial cells generated by alpha-particle exposure

PURPOSE

To investigate the cytogenetic changes and DNA double-strand break (DSB) rejoining of transformed cell lines generated from human bronchial epithelial cells by alpha-particle exposure.

MATERIALS AND METHODS

Transformed cell lines were derived from the HPV 18-immortalized human bronchial epithelial cell line BEP2D generated by 1.5 Gy of alpha-particles emitted by a 238Pu source. Two cell lines, BERP35T1 and BERP35T4, were investigated. Karyotypes were analyzed by trypsin/Giemsa banding. Cell survival was estimated by colony assay. PFGE was used to detect the DNA DSB. mRNA expression was analyzed by RT-PCR.

RESULTS

Abnormal chromosomes 2 and 12 with elongated long arm and deletions of chromosomes 2, 12, 13 and 17 were observed in the transformed cell lines. BERP35T4 showed a much higher proportion of polyploid cells (40.5%) compared with parental BEP2D cells and the BERP35TI cell line (5%). BERP35T1 and BERP35T4 showed a markedly lower capacity for rejoining of gamma-ray-induced DNA DSB and increased radiosensitivity compared with parental BEP2D cells. The analysis of mRNA levels revealed a 2.5- to 6.5-fold down-regulated expression of the DNA repair genes XRCC-2, XRCC-3 and Ku80 in BERP35T1 and BERP35T4 cells.

CONCLUSION

The karyotypic changes of chromosomes 2, 12, 13 and 17 and the deficiency of DSB rejoining could be related to the malignant transformation processing of BEP2D cells initiated by alpha-particle exposure.

The measurement of three dimensional dose distribution of a ruthenium-106 ophthalmological applicator using magnetic resonance imaging of BANG polymer gels

The BANG (MGS Research Inc., Guilford, CT) polymer gel has been used as a dosimeter to determine the three-dimensional (3D) dose distribution of a ruthenium-106 (Ru-106) ophthalmologic applicator. An eye phantom made of the BANG gel was irradiated with the Ru-106 source for up to 1 h. The phantom and a set of calibration vials were scanned simultaneously in a GE 1.5 T MR imager using the Hahn spin-echo pulse sequence with a TR of 2000 ms and two TEs of 20 ms and 100 ms. The T(2) values were evaluated on a pixel-by-pixel basis using custom-built software on a DEC alpha workstation and converted to dose using calibration data. Depth doses and isodose lines of the Ru-106 eye-plaque were generated. It is concluded that the BANG gel dosimetry offers the potential for measuring the 3D dose distributions of an ophthalmologic applicator, with high spatial resolution and relatively good accuracy.

O(6)-Methylguanine-DNA methyltransferase promoter hypermethylation shifts the p53 mutational spectrum in non-small cell lung cancer

The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) removes mutagenic adducts from the O6 position of guanine, thereby protecting the genome against G to A transition mutations. MGMT is inactivated by promoter hypermethylation in many human cancers and has been associated with G to A mutations in K-ras in colorectal cancer. We hypothesized that MGMT promoter hypermethylation would be associated with an increase in G to A transitions in the p53 gene in non-small cell lung cancer (NSCLC). p53 mutations were detected by both dideoxy sequencing and p53 GeneChip analysis in 92 patients with primary NSCLC. Methylation of the promoter region of the MGMT gene was determined using methylation-specific PCR and was present in 27 of 92 (29%) tumors. Hypermethylation of the MGMT promoter was more common in adenocarcinoma than in other histological types of NSCLC and was also more common in poorly differentiated tumors. MGMT promoter hypermethylation was present significantly more often in tumors with a G to A mutation in p53 (9 of 14; 64%) than in tumors with other types of p53 mutations (11 of 41; 27%; P = 0.02) or in tumors with wild-type p53 (7 of 37; 18%; P = 0.006). MGMT promoter hypermethylation was also strongly associated with G to A transitions at CpG sites. Inactivation of the MGMT gene by promoter hypermethylation alters the pattern of p53 mutation in NSCLC.

Profiling of differentially expressed cancer-related genes in esophageal squamous cell carcinoma (ESCC) using human cancer cDNA arrays: overexpression of oncogene MET correlates with tumor differentiation in ESCC

PURPOSE

To examine the global gene expression of cancer-related genes in esophageal squamous cell carcinoma (ESCC) through the use of Atlas Human Cancer Array membranes printed with 588 well-characterized human genes involved in cancer and tumor biology.

EXPERIMENTAL DESIGN

Two human ESCC cell lines (HKESC-1 and HKESC-2) and one morphologically normal esophageal epithelium tissue specimen from the patient of which the HKESC-2 was derived were screened in parallel using cDNA expression arrays. The array results were additionally validated using semiquantitative PCR. The overexpression of oncogene MET was studied more extensively for its protein expression by immunohistochemistry in the two ESCC cell lines and their corresponding primary tissues and 61 primary ESCC resected specimens. Sixteen of these 61 ESCC cases also had available the corresponding morphologically normal esophageal epithelium tissues and were also analyzed for MET expression. The clinicopathological features associated with overexpression of the MET gene were also correlated.

RESULTS

The results of cDNA arrays showed that 13 cancer-related genes were up-regulated > or =2-fold (CDC25B, cyclin D1, PCNA, MET, Jagged 2, Integrin alpha3, Integrin alpha6, Integrin beta4, Caveolin-2, Caveolin-1, MMP13, MMP14, and BIGH3) and 5 genes were down-regulated > or =2-fold (CK4, Bad, IGFBP2, CSPCP, and IL-1RA) in both ESCC cell lines at the mRNA level. Semiquantitative RT-PCR analysis of 9 of these differentially expressed genes, including the MET gene, gave results consistent with cDNA array findings. The immunostaining results of the expression of MET gene showed that MET was overexpressed in both ESCC cell lines and their corresponding primary tumors at the protein level, validating the cDNA arrays findings. The results of the clinical specimens showed that the MET gene was overexpressed in ESCC compared with normal esophageal epithelium in 56 of 61 cases (92%). Moreover, the overexpression of MET protein was more often seen in well/moderately differentiated than in poorly differentiated ESCC.

CONCLUSIONS

Multiple cancer-related genes are differentially expressed in ESCC, the oncogene MET is overexpressed in ESCC compared with normal esophageal epithelium, and its protein overexpression correlates with tumor differentiation in ESCC.

Effect of MOI ratio on the composition and yield of chimeric infectious bursal disease virus-like particles by baculovirus co-infection: deterministic predictions and experimental results

Virus-like particles (VLPs) are empty particles consisting of virus capsid proteins that closely resemble native virus but are devoid of the native viral nucleic acids and therefore have attracted significant attention as noninfectious vaccines. A recombinant baculovirus, vIBD-7, which encodes the structural proteins (VP2, VP3, and VP4) of infectious bursal disease virus (IBDV), produces native IBD VLPs in infected Spodoptera frugiperda insect cells. Another baculovirus, vEDLH-22, encodes VP2 that is fused with a histidine affinity-tag (VP2H) at the C-terminus. By co-infection with these two baculoviruses, hybrid VLPs with histidine tags were formed and purified by immobilized metal affinity chromatography (Hu et al., 1999). Also, we demonstrated that varying the MOI ratio of these infecting viruses altered the extent of VP2H incorporated into the particles. A dynamic mathematical model that described baculovirus infection and VLP synthesis (Hu and Bentley, 2000) was adapted here for co-infection and validated by immunofluorescence labeling. It was shown to predict the VLP composition as a dynamic function of MOI. A constraint in the VP2H content incorporated into the particles was predicted and shown by experiments. Also, the MOI ratio of both infecting viruses was shown to be the major factor influencing the composition of the hybrid particles and an important factor in determining the overall yield. ELISA results confirmed that VP2H was exhibited to a varied extent on the outer surface of the particles. This model provides insight on the use of virus co-infection in virus-mediated recombinant protein expression systems and aids in the optimization of chimeric VLP synthesis.

Identification of differentially expressed genes in esophageal squamous cell carcinoma (ESCC) by cDNA expression array: overexpression of Fra-1, Neogenin, Id-1, and CDC25B genes in ESCC

PURPOSE

This study aims to identify differentially expressed genes in esophageal squamous cell carcinoma (ESCC) through the use of a membrane-based cDNA array.

EXPERIMENTAL DESIGN

Two newly established human ESCC cell lines (HKESC-1 and HKESC-2) and one corresponding to a morphologically normal, esophageal epithelium tissue specimen, prospectively collected from the HKESC-2-related patient, were screened in parallel using a cDNA expression array containing gene-specific fragments for 588 human genes spotted onto nylon membranes.

RESULTS

The results of cDNA expression array showed that 53 genes were up-regulated 2-fold or higher and 8 genes were down-regulated 2-fold or higher in both ESCC cell lines at the mRNA level. Semiquantitative RT-PCR analysis of a subset of these differentially expressed genes gave results consistent with cDNA array findings. Four of the differentially expressed genes that belong to the categories of oncogenes/tumor suppressor genes (Fra-1 and Neogenin) and cell cycle-related genes (Id-1 and CDC25B) were studied more extensively for their protein expression by immunohistochemistry. The two ESCC cell lines and their corresponding primary tissues, 61 primary ESCC resected specimens and 16 matching, morphologically normal, esophageal epithelium tissues were analyzed. The immunostaining results showed that Fra-1, Neogenin, Id-1, and CDC25B were overexpressed in both ESCC cell lines and their corresponding primary tumors at the protein level, validating the microarray findings. The results of the clinical specimens showed that the Fra-1 gene was overexpressed in ESCC compared with normal esophageal epithelium in 53 of 61 cases (87%), Neogenin in 57 of 61 cases (93%), Id-1 in 57 of 61 cases (93%), and CDC25B in 48 of 61 cases (79%). Furthermore, the expression of Fra-1, Neogenin, and Id-1 in ESCC correlated with tumor differentiation.

CONCLUSIONS

Overall, this study demonstrates that multiple genes are differentially expressed in ESCC and provides the first evidence that oncogenes Fra-1 and Neogenin and cell cycle-related genes Id-1 and CDC25B are overexpressed in ESCC.

From transforming growth factor-beta signaling to androgen action: identification of Smad3 as an androgen receptor coregulator in prostate cancer cells

Although transforming growth factor-beta (TGF-beta) has been identified to mainly inhibit cell growth, the correlation of elevated TGF-beta with increasing serum prostate-specific antigen (PSA) levels in metastatic stages of prostate cancer has also been well documented. The molecular mechanism for these two contrasting effects of TGF-beta, however, remains unclear. Here we report that Smad3, a downstream mediator of the TGF-beta signaling pathway, functions as a coregulator to enhance androgen receptor (AR)-mediated transactivation. Compared with the wild-type AR, Smad3 acts as a strong coregulator in the presence of 1 nM 5alpha-dihydrotestosterone, 10 nM 17beta-estradiol, or 1 microM hydroxyflutamide for the LNCaP mutant AR (mtAR T877A), found in many prostate tumor patients. We further showed that endogenous PSA expression in LNCaP cells can be induced by 5alpha-dihydrotestosterone, and the addition of the Smad3 further induces PSA expression. Together, our findings establish Smad3 as an important coregulator for the androgen-signaling pathway and provide a possible explanation for the positive role of TGF-beta in androgen-promoted prostate cancer growth.

Increase of androgen-induced cell death and androgen receptor transactivation by BRCA1 in prostate cancer cells

Although mutations of the breast cancer susceptibility gene 1 (BRCA1) may play important roles in breast and prostate cancers, the detailed mechanism linking the functions of BRCA1 to these two hormone-related tumors remains to be elucidated. Here, we report that BRCA1 interacts with androgen receptor (AR) and enhances AR target genes, such as p21((WAF1/CIP1)), that may result in the increase of androgen-induced cell death in prostate cancer cells. The BRCA1-enhanced AR transactivation can be further induced synergistically with AR coregulators, such as CBP, ARA55, and ARA70. Together, these data suggest that the BRCA1 may function as an AR coregulator and play positive roles in androgen-induced cell death in prostate cancer cells and other androgen/AR target organs.

Production of HIV-1 gp120 in packed-bed bioreactor using the vaccinia virus/T7 expression system

The HeLa cell-vaccinia virus system is an attractive method for producing recombinant mammalian proteins with proper post-translation modifications. This approach is especially important for the production of HIV-1 envelope glycoprotein, gp120, since more than half of its total mass is due to carbohydrates. A recombinant vaccinia virus/T7 RNA polymerase expression system was developed to express and produce large amounts of gp120 tagged with six histidine residues. In this system, the expressed T7 RNA polymerase from one virus drives the transcription of the gp120 encoded in the second virus. During the process development phase, the following parameters were studied: infection time, infection duration, multiplicity of infection, ratio of the two viruses, medium composition, and medium replacement strategy during the infection phase. The chosen production method was based on using the packed-bed bioreactor. The HeLa cells were immobilized on fibrous disks (Fibra-Cel) packed in an internal basket positioned in a vertically mixed bioreactor (Celligen Plus), and 25 g of carriers were packed in a 1.6-L (working volume) reactor. The process included a growth stage followed by a production stage. In the growth stage, the bed was perfused with a serum-containing medium, allowing the cells to grow to saturation, and in the production stage, done using serum-free medium, the cells were infected with the two recombinant viruses. The expressed protein was secreted, collected from the culture fluid, and purified. The specific production was found to be between 2 and 3 microg of protein/10(6) cells, and the volumetric production was around 10 mg/50 g carriers.

Mutational analysis of the PTEN/MMAC1 gene in primary oesophageal squamous cell carcinomas

AIM

To investigate whether PTEN/MMAC1 mutations play a role in the carcinogenesis of oesophageal squamous cell carcinoma.

METHODS

A panel of 33 primary oesophageal squamous cell carcinoma tumour samples and 20 corresponding morphologically normal tissues was examined for mutations in all nine exons of the PTEN/MMAC1 gene by means of polymerase chain reaction single strand conformational polymorphism analysis (PCR-SSCP) and direct DNA sequencing methods.

RESULTS

Only one of 33 oesophageal squamous cell carcinomas showed an aberrant SSCP band. Further sequencing analysis of this sample revealed an 802 -29 T-->C substitution in intron 7. PTEN/MMAC1 mutations were not found in the mutational "hot spot" in exon 5, even after direct sequencing of six oesophageal squamous cell carcinoma samples and three normal tissues. However, a deletion of one nucleotide T at position 492 +8 in intron 5 was seen in all samples.

CONCLUSION

These results suggest that PTEN/MMAC1 mutations do not play a major role in the carcinogenesis of oesophageal squamous cell carcinoma.

Enhancing yield of infectious Bursal disease virus structural proteins in baculovirus expression systems: focus on media, protease inhibitors, and dissolved oxygen

Structural proteins of the poultry pathogen, infectious bursal disease virus (IBDV), were expressed in the baculovirus/insect cell expression system. To date, several reports have indicated that animal virus structural proteins are expressed only at low yield in this system. In this article, several factors were examined to enhance yield. These include medium, dissolved oxygen level, and the addition (in vivo and in vitro) of protease inhibitors. Specifically, two media were compared, and SF-900 II was superior to Ex-Cell 401 for cell growth and IBDV protein expression. A cocktail of protease inhibitors including phenylmethyl sulfonyl fluoride (PMSF), leupeptin, and ethylenediamine tetraacetic acid (EDTA) minimized proteolysis in vitro. Also, aprotinin and pepstatin A deterred product degradation in vivo and increased the product yield nearly 2-fold. Finally, in 3 L bioreactors, a dissolved oxygen tension of 50% DO (air saturation) was optimal. Results demonstrated that several relatively simple adjustments to the baculovirus system significantly improved the yield of IBD virus structural proteins.

Differential induction of androgen receptor transactivation by different androgen receptor coactivators in human prostate cancer DU145 cells

Recently identified androgen receptor (AR) coactivators were used in this study to determine whether the specificity of sex hormones and antiandrogens could be modulated at the coactivator level. We found that ARA70 is the best coactivator to confer the androgenic activity on 17beta-estradiol. Only ARA70 and ARA55 could increase significantly the androgenic activity of hydroxyflutamide, a widely used antiand rogen for the treatment of prostate cancer. None of the AR coactivators we tested could significantly confer androgenic activity on progesterone and glucocorticoid at their physiological concentrations (1-10nM). We also found that ARA70, ARA55, and ARA54, but not steroid receptor coactivator-1 (SRC-1) and Rb, could significantly enhance the delta5-androstenediol-mediated AR transactivation. Furthermore, in comparing the relative specificity of these coactivators to AR in DU145 cells, our results suggested that ARA70 has a relatively higher specificity and that SRC-1 can enhance almost equally well many other steroid receptors. Finally, our data demonstrated that AR itself and some select AR coactivators such as ARA70 or ARA54 could, respectively, interact with CBP and p300/CBP-associated factors that have histone acetyl-transferase activity for assisting chromatin remodeling. Together, our data suggest that the specificity of sex hormones and antiandrogens can be modulated by some selective AR coactivators. These findings may not only help us to better understand the specificity of the sex hormones and antiandrogens, but also facilitate the development of better antiandrogens to fight the androgen-related diseases, such as prostate cancer.

Telomerase activity and in situ telomerase RNA expression in oral carcinogenesis

To investigate the role of telomerase in oral carcinogenesis, we assayed telomerase activity in various oral tissues by a modified telomeric repeat amplification protocol (TRAP) analysis. Also, using digoxigenin-labeled probes, we measured the in situ expression of human telomerase RNA component (hTR) in paired oral squamous cell carcinomas (OSCC) and adjacent non-cancerous matched tissue (NCMT). We detected telomerase activity in three OSCC cell lines, but not in primary oral keratinocytes. In patient samples, most OSCC (36/42, 86%) and oral premalignant lesions (8/12, 67%) possessed telomerase activity. In addition, 6 of 27 (22%) NCMT contained weak telomerase activity. In situ hybridization showed that hTR was expressed in almost all OSCC (23/27, 85%) as well as in the majority of NCMT (20/25, 80%). In most cases, accumulation of hTR was observed both in the nucleus and cytoplasm of epithelial cells. A correlation between hTR expression and more advanced tumor grade was observed. The appearance of telomerase activation and hTR expression during oral carcinogenesis was different. This study indicates that the activation of telomerase is an early and frequent event in OSCC.

Chimeric infectious bursal disease virus-like particles expressed in insect cells and purified by immobilized metal affinity chromatography

Chimeric virus-like particles (VLPs) of infectious bursal disease virus (IBDV) were produced by coinfecting Spodoptera frugiperda (Sf-9) insect cells with two recombinant baculoviruses, vIBD-7 and vEDLH-22. vIBD-7 encodes VP2, VP3, and VP4 of the IBDV structural proteins. vEDLH-22 encodes VP2 with five histidine residues at the carboxy-terminus (VP2H). Coinfection produced hybrid VLPs composed of VP2, VP2H, and VP3. The additional histidine residues on VP2H enabled the efficient purification of VLPs based on immobilized metal affinity chromatography (IMAC). These results demonstrated that the VLPs formed are comprised of chimeric subunits with attached affinity ligands, and further, that sufficient His5 ligand was available for binding to the IMAC metal-chelating resin. Additionally, these novel particles were fully characterized for antigenicity by a series of monoclonal antibodies, and appeared identical to the two wild-type IBDV strains contributing subunits to the chimeric VLP. IMAC purification provides a promising low-cost and simple scheme to purify VLPs as vaccines.

Determination of the thermogenesis curves and studies of the thermodynamics and thermokinetics of seed germination

The thermogenesis curves of the germination of different rice and tree seeds were determined and studied by using a newly constructed microcalorimeter. The thermogenesis curves of the germination of the seeds demonstrate the existence of physiological triphasic patterns, which include imbibition, activation and growth stages in the germination process. The thermodynamics and thermokinetics of the main growth phase of the growth stage in the germination process have been studied. The growth heat effect (deltaH), the growth rate constant (k), the growth inhibitory factor (s) and deceleration rate constant (beta) have been determined and calculated, In addition, the experimental thermokinetic equations of the growth stage in the seed germination process have been established.

[Ultrastructural study of 14 cases of dermatofibrosarcoma protuberans]

14 cases of dermatofibrosarcoma protuberans (DFSP) were investigated with electron microscopy. Perineural cells, fibroblasts and primitive mesenchymal cells were found in all cases with perineural cells as the most prominent component. The findings suggest that DFSP is a tumor with heterogeneity, most probably arising from primitive dermal mesenchymal cells which have the potential for differentiation toward different cell lines, especially toward perineural cells.

Sister chromatid exchanges in lymphocytes of early cases of nasopharyngeal carcinoma and in 100 healthy subjects

Sister chromatid exchange rate was studied in 12 early diagnosed cases of nasopharyngeal carcinoma and in their paired controls. Exchange frequencies were also analyzed in 100 healthy subjects distributed in four regions of Hunan Province and correlated to nationality, age and sex. The incidence of sister chromatid exchange was significantly higher in the cancer patients than in the normal controls. No correlation was found between the frequency of sister chromatid exchange and region, nationality, age or sex.

Evidence for a major premutagenic ethyldeoxythymidine-DNA adduct in an in vivo system: N-nitroso-N-ethylurea-treated Salmonella typhimurium

Mutagenesis induced by N-nitroso-N-ethylurea (NEU) was assayed in four strains of Salmonella typhimurium which are known to be reverted to histidine prototrophy by mutations at A-T base pairs and by extragenic suppression. NEU-induced revertants were characterized for the presence of extragenic suppressors by their sensitivities to the histidine analogue, thiazolealanine. In strains carrying the plasmid, pKM101, only a small percentage of the revertants was due to suppressors, indicating that NEU gives rise to a major premutagenic adenine or thymidine-DNA adduct. In strains without plasmid, mutagenesis was much less efficient and resulted mainly from suppressors. Apparently error-prone DNA-repair plays an important role in mutagenesis via the A or T-DNA adduct in the plasmid-containing strains. Ethylmethanesulfonate (EMS), a mutagen known to form ethyladenines but not ethylthymidines, induced mutagenesis that resulted mainly from suppressors in all strains, and there was little inter-strain difference in the sensitivity to EMS. Since NEU, but not EMS, forms ethylthymidines in appreciable yield, and only NEU induced high percentages of revertants with mutations at A-T base pairs, it appears that at least one ethylthymidine is a major premutagenic adduct in NEU-induced mutagenesis.

Mutagenesis by N-nitroso compounds in Salmonella typhimurium TA102 and TA104: evidence for premutagenic adenine or thymine DNA adducts

Mutagenesis induced by the N-nitroso compounds: N-nitrosomethylurea, N-nitrosoethylurea, N-nitrosodi-n-propylamine and N-nitrosopyrrolidine was measured in Salmonella typhimurium TA100, TA102 and TA104. TA100 detects damage mainly at G-C base pairs while TA102 and TA104 can detect damage at A-T base pairs. In general all strains were similarly sensitive, except that TA104 was much less sensitive to high doses of N-nitroso-N-methylurea. In TA104 a significant percentage of the revertants induced by all agents except NMU resulted from point mutations at A-T base pairs, indicating that adenine or thymine DNA adducts are important premutagenic adducts formed by certain N-nitroso compounds.