[Challenges and strategies in the treatment of neovascular age-related macular degeneration]

Neovascular age-related macular degeneration (nAMD) is a leading cause of blindness in the elderly, and anti-vascular endothelial growth factor (VEGF) therapy is currently the primary treatment approach. However, the real-world effectiveness of nAMD treatment is not always satisfactory and faces various challenges. Frequent administration and follow-up burdens can lead to decreased patient compliance during long-term treatment, resulting in suboptimal outcomes. Some lesions exhibit poor or no response to anti-VEGF treatment, leading to difficulties in maintaining or even declining visual acuity. Factors such as lesion fibrosis and tissue atrophy can contribute to visual deterioration. Therefore, standardizing and individualizing treatment plans, along with enhancing comprehensive monitoring and management throughout the disease course, are crucial improvement measures. The evidence-based guidelines for diagnosis and treatment of age-related macular degeneration in China, released in 2023, provide guidance for standardized clinical diagnosis and treatment. Meanwhile, research and development of new drugs and administration methods are anticipated for the future.

[Investigation of serum surface active protein D and clara cell protein levels in workers exposed to silica dust in ferrous metal foundry]

Objective: To investigate the levels of serum surface active protein D (SP-D) and clara cell protein (CCl6) in workers exposed to black silica dust, and analyze its influencing factors. Methods: From July to September 2021, 174 workers in 37 positions exposed to silica dust in 5 ferrous metal foundry were investigated by cross-sectional research method. The exposure concentration of silica dust workers was obtained through occupational health field investigation and detection, and the general situation of the study subjects was obtained through questionnaire survey and peripheral blood was collected. Double antigen sandwich enzyme-linked immunosorbent assay (ELISA) was used to detect the concentrations of SP-D and CC16 in serum of workers. The mean values were compared by one-way ANOVA, and the influencing factors of SP-D and CC16 concentrations in serum were analyzed by ordered multiple logistic regression. Results: The time-weighted average concentration (C-TWA) of 174 workers exposed to silica dust (respirable dust) ranged from 0.09 mg/m(3)~3.58 mg/m(3), and the C-TWA overstandard rate of dust exposed workers was 32.18% (56/174) , with differences among workers in different positions (χ(2)=28.85, P<0.001) . The highest concentration of silica dust was (0.82±0.11) mg/m(3). Using C-TWA<50% OEL occupational exposure limit (OEL) as reference, serum SP-D concentration in workers with ≥50% OEL was increased (OR=4.95, 95%CI: 1.86~13.17, P=0.001) , while CC16 concentration was decreased (OR=0.15, 95%CI: 0.05~0.40, P<0.001) ; Serum CC16 concentration decreased in workers exposed to silica dust C-TWA≥OEL (OR=0.46, 95%CI: 0.28~0.98, P=0.043) . Compared with those with low occupational health literacy, the serum SP-D concentration of workers with high occupational health literacy decreased (OR=0.48, 95%CI: 0.25~0.92, P=0.027) and CC16 concentration increased (OR=2.09, 95%CI: 1.10-3.97, P=0.024) . Conclusion: When no abnormality was found in the physical examination of workers, the serum SP-D and CC16 concentration levels changed, and the change was related to the concentration of workers exposed to silica dust.

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

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

Surgical treatment of tethered cord syndrome showed promising outcome in young children with short duration

OBJECTIVE

Aside from the severity, surgical interventions for the treatment of neurological dysfunctions remain controversial. This study aimed to find factors predicting the benefits of tethered cord syndrome (TCS) surgery.

PATIENTS AND METHODS

80 children with TCS were included and followed up for pre- and post-operative factors along with neurophysiological analysis. Outcomes were assessed by univariate and multivariate analysis.

RESULTS

Surgical treatment not only improved preoperative signs and symptoms in 79% of TCS patients but it showed to be an efficient procedure for the occurrence of future neurological defects. Univariate analysis also revealed that surgical intervention in TCS children (age <1 year) can modulate filar lipoma location and cutaneous abnormalities three months after surgery. Neurophysiological assessment revealed only 5.0% of surgical complications in TCS patients. Two patients had cerebrospinal fluid leakage, and two cases of CNS infection were detected.

CONCLUSIONS

Surgical intervention is highly recommended for the prevention of neurological deficits in children with TCS. Electrophysiological monitoring revealed rare complications following the surgery.

[A meta-analysis on prevalence of primary angle-closure glaucoma in the middle-aged and elderly chinese population]

Objective: To evaluate the prevalence and relevant factors of primary angle-closure glaucoma (PACG) in the middle-aged and elderly (40 years old and above) Chinese population. Methods: Epidemiological literature (of English and/or Chinese language) on prevalence of PACG in China between 2000 and 2022 were retrieved from PubMed, Embase, Web of Science, CNKI, and Wanfang database. Two researchers conducted the process of document retrieval, inclusion, quality assessment and data extraction independently based on inclusion and exclusion criteria. Disagreement was resolved by consensus with a third researcher. The heterogeneity among studies was assessed by using the I² statistics, and a corresponding model was used for the meta-analysis. Subgroup analysis (gender, age, survey date, place of residence, diagnostic criteria, and temperature zone), as well as sensitivity analysis and publication bias analysis, were conducted. Results: Twenty-three studies were included in this research. Among them, eight were of high-quality and fifteen were of middle-quality. In the past 20 years, the PACG prevalence in middle-aged and elderly (40 years and older) Chinese population was 1.35% (95%CI:1.08% to 1.61%). Chinese women (1.40%) were more likely to have PACG than men (0.96%, P<0.01). The PACG prevalence had a positive correlation with age (P<0.01). The prevalence was similar between urban (1.3%) and rural (1.2%, P=0.61) areas. The PACG prevalence from studies in which the diagnostic criteria of PACG requested the symptom of vision or optic nerve damage (1.1%) was lower than that those without such requirement (1.7%, P<0.01). In mid-temperate zone, the prevalence was higher (1.7%, P=0.02). Conclusions: The PACG prevalence in middle-aged and elderly (40 years old and above) Chinese population was 1.35% in the last 20 years. The prevalence of PACG varies across age, regions, and other variations. This risk is higher in the elderly, women, and people in cold regions among Chinese population.

[Clinical report of hoding cricoarytenoid joint reduction with visual laryngoscope under intravenous anesthesia]

Objective: To investigate the reduction effect of hoding cricoarytenoid joint reduction with visual laryngoscope under intravenous anesthesia. Methods: The therapeutic effects of 40 patients with arytenoid dislocation(AD)treated by closed reduction in the single center from January 2020 to September 2021 were retrospectively analyzed, including 21 males and 19 females, median age 48 years. The etiology, symptoms, preoperative evaluation methods, reduction mode, reduction times, and the recovery of arytenoid cartilage movement and sound after reduction were evaluated and analyzed. Results: All patients had obvious hoarseness and breath sound before treatment. Under stroboscopic laryngoscope or electronic nasopharyngoscope, different degrees of vocal cord movement disorder and poor glottic closure can be seen. There were 28 cases of left dislocation, 9 cases of right dislocation and 3 cases of bilateral dislocation. The etiology of dislocation of cricoarytenoid joint: 25 cases (62.5%) of tracheal intubation under general anesthesia were the most common causes, was as follows by laryngeal trauma, gastroscopy, cough, vomiting and so on. Among them, 28 cases of reduction were initially diagnosed in our department, and 12 cases were diagnosed later after failure of reduction treatment. Of the 40 patients, 6 underwent reduction 24 hours after dislocation; 18 cases from 3 days to 1 month; 7 cases from 1 to 3 months; 6 cases were reset in 3~6 months; Over 6 months in 3 cases. After one reduction, 10 cases (10/40, 25%) recovered normal pronunciation, 14 cases (14/40, 35%) recovered normal pronunciation after two reduction, 10 cases (10/40, 25%) recovered normal pronunciation after three times, 2 cases (2/40, 5%) recovered normal pronunciation after four times, and 1 case (2.5%) recovered normal pronunciation after five times. Thin slice CT scan of larynx and cricoarytenoid joint reconstruction showed the types of AD: subluxation in 37 cases (92.5%) and total dislocation in 3 cases; 28 cases of left dislocation, 9 cases of right dislocation and 3 cases of bilateral dislocation; 29 cases (72.5%) had posterior dislocation and 11 cases (27.5%) had anterior dislocation. All patients were treated by intravenous anesthesia with arytenoid cartilage clamped by cricoarytenoid joint reduction forceps under visual laryngoscope. The curative effect was evaluated by stroboscopic laryngoscope and/or voice analysis at 1-2 weeks after operation. The vocal cord movement returned to normal and the pronunciation was good in 37 cases (92.5%). Conclusions: Hoding cricoarytenoid joint reduction with the vision laryngoscope under intravenous anesthesia is easy to operate and the reduction effect is more stable. It is a effective method for AD.

[Expression and diagnostic value of macrophage inflammatory protein-3α in patients with hepatitis B-related acute-on-chronic liver failure]

Objective: To screen serum protein markers and evaluate their diagnostic application value in hepatitis B-related acute-on-chronic liver failure (HBV-ACLF). Methods: Serum samples of patients with HBV-ACLF, chronic hepatitis B (CHB) and normal healthy volunteers (n = 5/group) were determined by cytokine antibody chip in line with the Chinese Diagnostic Standards Study for HBV-ACLF (COSSH-ACLF) cohort. The differentially expressed proteins significance were identified by microarray analysis and prediction. The preliminary serological markers of HBV-ACLF were screened for diagnosis. The potential markers were determined by enzyme-linked immunosorbent assay (ELISA), area under the receiver operating characteristic curve (AUROC) analysis and liver tissue immunohistochemistry for the diagnosis of HBV-ACLF. Student t-test or Mann-Whitney U test were used to compare the continuous measurement data between the two groups, and analysis of variance and Kruskal-Wallis test were used to compare the continuous measurement data between multiple groups. Results: Cytokine antibody chip preliminary screening results showed that the expression levels of these six cytokines, namely, macrophage inflammatory protein 3α (MIP-3α), hepatocyte growth factor, E-selectin, osteopontin, growth differentiation factor 15 and carcinoembryonic antigen-related cellular adhesion molecule 1 were significantly increased in the HBV-ACLF group. Among them, the expression level of MIP-3α was significantly higher in the HBV-ACLF group (99.6 times higher than CHB group and 146.9 times higher than healthy volunteers' group, respectively, P < 0.0001) as validated by serum ELISA in 132 HBV-ACLF cases, 91 CHB cases and 72 healthy volunteers. AUROC analysis showed that the high expression of MIP-3α could be used as a marker to distinguish patients with HBV-ACLF from CHB. The AUROC was 0.995 (95% CI: 0.990 ~ 1.000), with sensitivity and specificity of 95.5% and. 98.9%, respectively. Immunohistochemistry showed that MIP-3α was positively expressed in HBV-ACLF-derived liver tissues, and negatively expressed in CHB-derived liver and normal liver tissues. Conclusion: Serum MIP-3α level is closely related to the pathological characteristics of HBV-ACLF. Therefore, it may be used as a potential serological marker for the diagnosis of HBV-ACLF.

Enzymatic acylation of lutein with a series of saturated fatty acid vinyl esters and the thermal stability and anti-lipid oxidation properties of the acylated derivatives

Lutein was enzymatically acylated with saturated fatty acid vinyl esters of different lengths of carbon chain (C₆ -C₁₄ ) under the action of Candida antarctica lipase B (Novozyme 435). The acylation reaction was optimized by considering substrate molar ratio, reaction solvent, type of enzyme, and reaction time. The highest yield (88%) was obtained using the Novozyme 435 to catalyze the acylation reaction of lutein and vinyl decanoate (lutein/vinyl decanoate molar ratio of 1/10) for 16 h in methyl tert-butyl ether. Ten lutein esters were synthesized, isolated, and purified, which were characterized by Fourier-transform infrared spectroscopy, high-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy. We found that the acylation of lutein improved its antioxidant capacity in lipid system and thermal stability. Our study extended the potential application of lutein in lipophilic food, cosmetic, and pharmaceutical industries. Practical Application: Enzyme acylation of lutein improved its antioxidant capacity in lipid system and thermal stability, extended its potential application in food, cosmetic, and pharmaceutical industries. In addition, our study also provided a new perspective and cognition for the further development and utilization of lutein.

[PD-1/PD-L1 expression and its interaction with interferon-γ in Toxoplasma gondii-infected mice at middle and late pregnancy]

OBJECTIVE

To explore the dynamic expression of programmed cell death-1 (PD-1) and its ligand PD-L1 at the maternal-fetal interface of mice post-infection with Toxoplasma gondii at early pregnancy and examine its interaction with interferon-γ (IFN-γ).

METHODS

A total of 20 mice at day 0 of pregnancy were randomly assigned into 4 groups, including the 12-day pregnancy control group (12 dpn group), 12-day pregnancy and infection group (12 dpi group), 18-day pregnancy control group (18 dpn group) and 18-day pregnancy and infection group (18 dpi group), respectively. On the 6th day of the pregnancy, mice in the 12 dpi and 18 dpi groups were injected intraperitoneally with 150 tachyzoites of the T. gondii PRU strain, while mice in the 12 dpn and 18 dpn groups were injected with the same volume of PBS. All mice in the four groups were sacrificed on 12th and 18^th day of the pregnancy, and the number of placenta and fetus was counted and the weight of placenta and fetus was measured. Then, the placental and uterine tissues of the pregnant mice in each group were sampled for pathological examinations. The mRNA expression of PD-1, PD-L1, T. gondii surface antigen SAG-1 and IFN-γ genes was quantified using a quantitative real-time PCR (qPCR) assay, and the correlation between PD-1 and IFN-γ expression was examined. In addition, the 12 dpn group, 12 dpi group, 18 dpn group, 18 dpi group, PBS negative control of the 12 pdi group and PBS negative control of the 18 dpi group were assigned, and the PD-1 expression was determined in the uterine and placenta tissues of the pregnant mice.

RESULTS

Adverse pregnant outcomes were seen in mice in the 12 dpi and 18 dpi groups, including placental dysplasia and fetal maldevelopment, and the placental weights and fetal body weights were significantly lower in mice in the 12 dpi and 18 dpi groups than those in the 12 dpn and 18 dpn groups (t = 5.52, 11.44, 12.63 and 11.67, all P < 0.01). The histopathological examinations showed that the decidua and junctional regions of the placental tissues were loosely connected in the 12 dpi and 18 dpi groups, and a large number of inflammatory cells infiltration and congestion were seen in the placental and uterine tissues. qPCR assay detected significant differences in PD-1, PD-L1, IFN-γ and SAG-1 expression in the placental and uterine tissues among the 12 dpn, 12 dpi, 18 dpn and 18 dpi groups (F = 22.48, 51.23, 9.61, 47.49, 16.08, 21.52, 28.66 and 238.90, all P < 0.05), and the PD-1, PD - L1, IFN - γ and SAG - 1 expression was all significantly higher in the placental and uterine tissues of mice in the 12 dpi group than in the 12 dpn group (all P values < 0.05). The PD-1 and PD-L1 expression was significantly lower in the placental tissues of mice in the 18 dpi group than in the 18 dpn group (all P values < 0.05), and the IFN-γ and SAG-1 expression was significantly higher in the placental and uterine tissues of mice in the 18 dpi group than in the 18 dpn group (all P values < 0.05), while the PD-1 and PD-L1 expression was significantly lower in the placental and uterine tissues of mice in the 18 dpi group than in the 12 dpi group (all P values < 0.05). Immunohistochemical staining showed PD-1 expression in the inflammatory cells of the placental tissues of mice in the 12 dpi group, and no apparent PD-1 expression in the 18 dpi group, while strongly positive PD-1 expression was found in the uterine epithelium of mice in the 12 dpi group, and mildly strong expression was in the 18 dpi group. In addition, the IFN-γ mRNA expression was positively correlated with the PD-1 mRNA expression in placental (r_s = 0.99, P < 0.01) and uterine tissues of mice in the 12 dpi group (r_s = 0.97, P < 0.01) and in placental (r_s = 0.82, P < 0.01) and uterine tissues of mice in the 18 dpi group (r_s = 0.81, P < 0.01).

CONCLUSIONS

Following T. gondii infection at early pregnancy, the PD-1 and PD-L1 expression shows a remarkable rise at middle pregnancy and a reduction at late pregnancy in placental and uterine tissues of mice, which appears the same tendency with IFN-γ expression during the same time period, and PD-1 expression positively correlates with IFN-γ expression. The dynamic expression of PD-1 and PD-L1 on the maternal-fetal interface of mice may be mutually mediated by IFN-γ induced by T. gondii infection.

Enzymatic acylation of rutin with benzoic acid ester and lipophilic, antiradical, and antiproliferative properties of the acylated derivatives

Rutin (3',4',5,7-tetrahydroxy-flavone-3-rutinoside) was enzymatically acylated with benzoic acid and its esters (methyl benzoate and vinyl benzoate) using Thermomyces lanuginosus lipase (Lipozyme TLIM). The acylation reaction was optimized by varying the reaction medium, reaction temperature, acyl donor, substrate molar ratio, and reaction time. The highest conversion yield (76%) was obtained in tert-amyl alcohol (60 °C, 72 hr) using vinyl benzoate (molar ratio of 1:10) as acyl donor. The acylation occurred at the 2'''-OH and 4'''-OH of the rhamnose unit and the 2''-OH position of the glucose moieties. Three novel rutin acylated derivatives (compounds 1-3) were purified and characterized by HR-MS and 1D and 2D NMR spectroscopy. We found that acylation significantly improved lipophilicity, capacity to inhibit lipid peroxidation, anticancer capacity and substantially maintained the antioxidant activity of rutin. This research provides important insights in the acylation of flavonoids with different glycosyl moieties. PRACTICAL APPLICATION: In this study, three novel rutin derivatives were successfully synthesized and the highest conversion yield (76%) was obtained by reacting the rutin and vinyl benzoate at molar ratio of 1:10 in tert-amyl alcohol for 72 hr at 60 °C. Introducing a benzoic acid substituent into rutin molecule significantly improved their lipophilicity and inhibition of lipid peroxidation in lipophilic system. Furthermore, this study demonstrated that acylation significantly improved anticancer capacity and substantially maintained the antioxidant activity.

[Study on the mechanisms of the intestinal tight-junction destruction caused by Blastocystis hominis infection in rats]

OBJECTIVE

To explore the mechanism of the intestinal barrier damage caused by Blastocystis hominis infections in rats.

METHODS

Thirty SD rats were randomly divided into the control group, and the 1-, 3-, 6- and 9-week-infection groups, of 6 rats in each group. Rats in each infection group were orally infected with B. hominis trophozoites at a density of 2 × 10⁸ parasites per rat, and the control group was given an equal volume of phosphate buffered saline solution. The 7-hour urine samples were collected 1, 3, 6 and 9 weeks post-infection for the measurement of the intestinal permeability. Then, rats were sacrificed using the cervical dislocation method, and the cecum specimens were collected for the detection of the intestinal epithelial cell permeability. The expression of tight junction-related Occludin and Claudin - 1 genes and apoptosis-related Bcl - 2 and Bax genes was quantified in cecum epithelial cells using the real-time fluorescent quantitative PCR (qPCR) assay, and cell apoptosis was detected in the rat cecum using the TdT-mediated dUTP nick-end labeling (TUNEL) assay.

RESULTS

The median urinary lactolose to mannitol ratios were 0.29, 0.72, 0.44, 0.46 and 0.38 in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 12.09, P < 0.05). B. hominis invasion and epithelial injury were observed in intestinal epithelial cells of rats infected with B. hominis, and transmission electron microscopy displayed the destruction of tight junctions between intestinal epithelial cells. The relative expression of Occludin, Claudin-1, Bcl-2 and Bax genes was 1.04, 0.62, 0.71, 0.68 and 0.96; 1.03, 0.61, 0.63, 0.76 and 0.86; 1.08, 0.70, 0.75, 0.74 and 1.03; and 1.00, 1.57, 1.33, 1.35 and 1.10 in the control group and the 1-, 3-, 6- and 9-week-infection groups, respectively, and all differences were statistically significant (F = 2.86, 2.85, 3.37 and 4.45, all P values < 0.05). The median number of positive staining cells were 1.00, 13.00, 9.00, 3.50 and 1.00 in rat cecum specimens in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 22.95, P < 0.01).

CONCLUSIONS

B. hominis infection may cause an increase in the rat intestinal permeability through triggering the apoptosis of intestinal epithelial cells to destroy the tight junction between intestinal epithelial cells, thereby destroying the intestinal barrier function.

[Research progress of neural precursor cells-expressed developmentally down-regulated protein-8 in liver diseases]

Neural precursor cells-expressed developmentally down-regulated protein-8 (NEDD8) is one of the important members of the ubiquitin family, which plays an important role in maintaining cell stability, cell cycle regulation, signal transduction, transcription, and translation, DNA repair, and tumorigenesis through covalently bound substrates (also known as neddylation modification). In recent years, studies have found that the dysfunction of NEDD8 and its related enzymes is common in liver diseases, and is widely involved in the biological processes of hepatitis, liver fibrosis, proliferation, invasion, apoptosis and autophagy of liver cancer cells. This article focuses on the research progress of NEDD8 in liver diseases.

A novel bacteriocin BM1029: physicochemical characterization, antibacterial modes and application

AIM

Bacteriocins with antimicrobial activity are considered as potential natural bio-preservatives to control the growth of food spoilage bacteria. The aim of this work was to characterize a novel bacteriocin BM1029 discovered from Lactobacillus crustorum MN047 and evaluate its antibacterial mechanism.

METHODS AND RESULTS

Bacteriocin BM1029 was purified by cation-exchange chromatography and reversed-phase chromatography. Antibacterial activity assay showed that BM1029 is antagonistic against both Gram-positive and Gram-negative bacteria. Furthermore, it was found that BM1029 showed low haemolysis with high stability to the pretreatment with different temperatures, pH and surfactants. Moreover electron microscopy and flow cytometry suggested that BM1029 inhibit indicator strains by damaging the cell envelope integrity. Cell cycle assay suggested that BM1029 arrested cell cycle in R-phase.

CONCLUSION

The novel bacteriocin BM1029 showed high bactericidal activity against Escherichia coli and Staphylococcus aureus through a cell envelope-associated mechanism.

SIGNIFICANCE AND IMPACT OF THE STUDY

Application of BM1029 inhibited the growth of indicator strains on beef meat storage at 4°C suggesting that this bacteriocin is promising to be used as a novel preservative in food processing and preservation.

[Advances in research on cell fate determinant Numb regulating liver cancer]

Liver cancer is one of the most common malignant tumors in China, ranking fifth in malignant tumors and the third in tumor-related deaths. As a membrane-related protein, the asymmetric distribution of cell fate determinant Numb plays a key role in cell differentiation. Research reports that Numb may be closely associated to the occurrence and development of tumors. Recently, scholars have gradually valued its important role in liver cancer. This article briefly reviews the structure of Numb molecule, relationship between Numb and tumorigenesis, the molecular mechanism of Numb-regulated tumors, and the role of Numb in the development of liver cancer.

[A concentration-response observation of hydromorphone combined with ropivacaine in labor analgesia]

Objective: To investigate the median effective dose (ED(50)) of hydromorphone and the appropriate concentration of ropivacaine combined with hydromorphone in epidural labor analgesia. Methods: One hundred and forty nulliparous women undergoing labor selected for delivery with epidural analgesia were enrolled in our hospital from January to June 2016. The first of top 50 women received 0.12% ropivacaine plus 20 μg/ml hydromorphone complex solution, then sequential women were used the modified sequential method to determine the ED(50) and ED(95) of hydromorphone. The other 90 women were randomly divided and receieved 0.08% ropivacaine and 15 μg/ml hydromorphone(H1 group), 0.10% ropivacaine and 15 μg/ml hydromorphone (H2 group), 0.12% ropivacaine and 15 μg/ml hydromorphone (group H3) respectively for epidural labor analgesia. In the course of labor, block levels of epidural analgesia, the Bromage scores, analgesia scores and fetal heart rate-uterine concraction were monitored. In addition, onset time of anesthesia, labor time, mode of delivery, cases of increased oxytocin using, neonatal Apgar score, incidence of nausea and vomiting, itching and fetal heart reduction were recorded. Results: The ED(50) and ED(95) values of hydromorphone were 10.49 (95% CI: 8.89-11.79) and 15.15 (95% CI: 13.25-22.25) μg/ml respectively. The onset time in group H1 was significantly longer than those in group H2 and H3((14.23±3.82) , ( 11.32±2.16), (10.83±2.56)min, respectively), the difference was statistically significant (t=5.854, 6.212, all P<0.05). Analgesic VAS score at 30, 60 and 90 min time points in H1 group was significantly higher than that in H2 group and H3 group (all P<0.05). VAS score at withdrawal in H1 group was significantly higher than that in group H3 ( (3.25±0.75) vs (0.27±0.12) ), the difference was statistically significant ( t=9.314, P<0.05). VAS scores at the fourth, fifth, sixth contractions after analgesia in H1 group were significantly higher than those in H2 and H3 groups (all P<0.05). The incidence of motor nerve block in group H3 was higher than that in group H1 and group H2 (26.67%, 6.66%, 3.33%, respectively), the difference was statistically significant (χ(2)=6.413, 4.320, all P<0.05). Conclusions: 0.10% ropivacaine combined with 15 μg/ml hydromorphone has a good analgesic effect, slight motor block, high safety and worthy clinical application for labor analgesia.

[Determination of 1-hydroxy-2-butanone in urine by gas chromatography]

Objective: To establish a method for the determination of 1-hydroxy-2-butanone in urine by gas chromatography. Methods: Urine samples were acidified with hydrochloric acid, and then stored in the refrigerator . After thawing under natural conditions, urine volume of 2.0 ml was extracted by C₁₈ solid phase, using methanol volume of 2.0 ml elution, detected by gas chromatography with FID detector and quantified by external standard method. Results: The measurement range of method is 0.986 ~32.88 μg/ml, correlation coefficient (r) =0.999 7, detection limit is 0.13 μg/ml; The recovery is 88.1% ~92.2% ; The precision is 1.4% ~3.2%. Conclusion: This method has a high sensitivity and simple processing. All technical indicators can meet the requirements of the determination method.

Reduced expression of serum miR-204 predicts poor prognosis of gastric cancer

Deregulation of microRNAs (miRNAs) is implicated in the initiation and progression of gastric cancer (GC). Previous studies have demonstrated that miR-204 was downregulated in GC tissues. However, its expression profile in serum samples and its potential for clinical value remain unknown. Real-time PCR was performed to evaluate the expression level of serum miR-204 in patients with GC. The association between serum miR-204 expression level and the clinical outcome of GC was then investigated. Our results showed that the expression of miR-204 in serum samples from GC patients was significantly lower than that in the healthy controls (P < 0.01). Serum miR-204 expression level of GC patients was significantly upregulated after receiving surgical resection (P < 0.01). In addition, serum miR-204 was associated with lymph node metastasis (P = 0.016), tumor differentiation (P = 0.001), and TNM stage (P = 0.005). GC patients with low serum miR-204 expression had shorter overall survival than those with high serum miR-204 expression (P = 0.004). Multivariate analysis revealed that serum miR-204 expression level was an independent risk factor for this malignant disease (HR = 3.629, 95%CI = 2.828-8.146, P = 0.015). In conclusion, our findings indicate that serum miR-204 may be employed as a novel biomarker for monitoring the treatment response and predicting the prognosis of GC.

Impact of adherence to GOLD guidelines on 6-minute walk distance, MRC dyspnea scale score, lung function decline, quality of life, and quality-adjusted life years in a Shanghai suburb

We performed a 1-year cluster-randomized field trial to assess the effect of standardized management of chronic obstructive pulmonary disease (COPD) on lung function and quality of life (QOL) measures in patients in China. We used the Global Initiative for Chronic Obstructive Lung Disease (GOLD) treatment guidelines and assessed indexes including pulmonary function, QOL, quality-adjusted life years (QALY), Medical Research Council (MRC) dyspnea scale, 6-min walk distance (6-MWD), number of emergency visits, and frequency of hospitalization. Of a total of 711 patients with chronic cough and asthma, 132 were diagnosed as having COPD and 102 participated in this study [intervention group (N = 47); control group (N = 55)]. We found that adherence to GOLD guidelines had a perceivable impact on 6-MWD, MRC dyspnea scale score, and QOL. The average QALY increased by 1.42/person/year in the intervention group, but declined by 0.95/person/year in the control group. We conclude that standardized management improves disease severity, QOL, and QALY in COPD patients when treatment protocols adhere to GOLD guidelines.

First Report of Phomopsis longicolla Causing Leaf Spot on Soybean in China

During July 2012, leaf spots affecting 60% of the leaves were observed on soybean cultivar He Feng 60 in fields near Shenyang City, Liaoning Province, leading to 5 to 10% yield loss. The leaf spots were associated with the leaf margins and were irregularly shaped, with brown to black margins and surrounded by a thin, yellow halo. Often, several spots merged to form large necrotic areas, which contained numerous pycnidia on the underside of the leaf. Small pieces (5 mm²) were excised from the margin of diseased and healthy tissue, surface-sterilized in 70% ethanol solution for 30 s and 0.1% mercuric chloride solution for 1 min, washed in three changes of sterile distilled water, and transferred to plates containing potato dextrose agar (PDA). Cultures were maintained in an incubator at 25°C with a 12 h dark/light photoperiod for 5 to 7 days. On PDA, colonies were white with yellow areas, floccose, dense, and moderately fast growing, attaining a diameter of 3.9 mm after 5 days and 9.0 mm after 14 days. Finally, large black stromata appeared after 28 days at 25°C. The conidiomata pycnidia were black, stomatic, globose, length 83.6 to 232 μm, width 37.9 to 146.3 μm and produced α-conidia that were unicellular, hyaline, sometimes two-guttulate, length 4.75 to 8.25 μm, width 1.50 to 3.00 μm. β-Conidia were not observed. To confirm the morphological identification, the ribosomal internal transcribed spacers (ITS1-5.8S-ITS2) from isolates were sequenced (GenBank Accession No. KC460334). The PCR products were cloned into a pMD-19T Cloning Vector (Sangon Biotech, Shanghai, China). The clones were purified with TIANprep Mini Plasmid Kit (Tiangen Biotech, Beijing, China) to get the full-length ITS sequence. BLAST analysis of the isolates showed 100% nucleotide sequence identity with Phomopsis longicolla (AY745021). Four additional primer pairs-large subunit (NL1/NL4), beta-tublin gene (Bt2a/Bt2b), translation elongation factor 1α gene(EF1-728F/EF1-986R), and act gene(ACT-512F/ACT-783R) (1,2)-were amplified and sequenced as described above. The large subunit gene, β-tubulin gene, and translation elongation factor 1α gene from isolates were sequenced (Sangon Biotech). BLAST analysis indicated that the isolates had 100% nucleotide sequence identity with P. longicolla (AB107259, HQ333514, and AF398896). Because the act gene sequence of P. longicolla was not in the NCBI database, this sequence had 94% nucleotide sequence identity with P. cuppatea (JN230389). To fulfill Koch's postulates, five leaves on five healthy soybean plants were inoculated with a conidial suspension (10⁶/ml). Plants inoculated with sterile water served as the noninoculated controls. Plants were incubated in the greenhouse at 25°C. All the inoculated leaves developed pinhead spots on the leaves, gradually increasing to large brown spots. Spots were irregularly shaped, brown and necrotic in the center, and surrounded by a yellow halo. Black pycnidia appeared after 10 days, whereas the noninoculated control plants remained asymptomatic. P. longicolla was consistently recovered from all inoculated plants, except the control. Morphological description of isolates was similar to that of Hobbs (3). However, as described by Hobbs and others, P. longicolla conidiomata pycnidia have prominent necks more than 200 μm long, opening by apical ostioles; locules are uniostiolate or multiostiolate, globose, up to 500 μm wide. The pycnidia size of isolates by frozen section method was smaller than that of Hobbs. Based on morphological and sequence comparisons, the pathogen of leaf spot disease is caused by P. longicolla. This is the first reported leaf spot caused by P. longicolla on soybean in China. References: (1) T. Boekhou et al. Stud. Mycol. 38:75, 1995. (2) P. W. Crous et al. Stud. Mycol. 75:37, 2013. (3) T. W. Hobbs et al. Mycologia 77:535, 1985.

Brain and spinal tumour

This study reviewed the epidemiology of brain and spinal tumours in Sarawak from January 2009 till December 2012. The crude incidence of brain tumour in Sarawak was 4.6 per 100,000 population/year with cumulative rate 0.5%. Meningioma was the most common brain tumour (32.3%) and followed by astrocytoma (19.4%). Only brain metastases showed a rising trend and cases were doubled in 4 years. This accounted for 15.4% and lung carcinoma was the commonest primary. Others tumour load were consistent. Primitive neuroectodermal tumour (PNET) and astrocytoma were common in paediatrics (60%). We encountered more primary spinal tumour rather than spinal metastases. Intradural schwannoma was the commonest and frequently located at thoracic level. The current healthcare system in Sarawak enables a more consolidate data collection to reflect accurate brain tumours incidence. This advantage allows subsequent future survival outcome research and benchmarking for healthcare resource planning.

Genetic diversity in wild populations of Paulownia fortune

The genetic diversities of 16 Paulownia fortunei populations involving 143 individuals collected from 6 provinces in China were analyzed using amplified fragment length polymorphism (AFLP). A total of 9 primer pairs with 1169 polymorphic loci were screened out, and each pair possessed 132 bands on average. The percentage of polymorphic bands (98.57%), the effective number of alleles (1.2138-1.2726), Nei's genetic diversity (0.1566-0.1887), and Shannon's information index (0.2692-0.3117) indicated a plentiful genetic diversity and different among Paulownia fortunei populations. The genetic differentiation coefficient between populations was 0.2386, while the gene flow was 1.0954, and the low gene exchange promoted genetic differentiation. Analysis of variance indicated that genetic variation mainly occurred within populations (81.62% of total variation) rather than among populations (18.38%). The 16 populations were divided by unweighted pair-group method with arithmetic means (UPGMA) into 4 groups with obvious regionalism, in which the populations with close geographical locations (latitude) were clustered together.

[Geographic distribution and gene sequencing of Paragonimus westermani in some areas of Guangdong Province]

OBJECTIVE

To investigate the current distribution of Paragonimus westermani in Guangdong Province.

METHOD

Snails and crabs collected from mountain streams in regional survey sites were dissected to detect cercarial and metacercarial infections of P. westermani. Domestic cats and dogs artificially infected with the collected metacercariae were also dissected to detect adult worms of P. westermani. The COI and ITS2 gene sequences of those adult worms were compared with those of known Paragonimus specimen deposited in the GenBank.

RESULTS

All of the first intermediate hosts in five survey sites of Liangkou, Nankun, Mountain, Dadong, Muxi, Guowu, were identified as Semisulcospira libertina, whose cercariae infection rates were 0.33%, 0.15%, 0.058%, 0.10%, and 0.05%, respectively; the second intermediate hosts in above five sites were all identified as Sinopotamon denticulatum, whose metacercariae infection rates were 100%, 100%, 38.09%, 55.36%, and 65.26%, respectively. The numbers of metacercariae in the five sites were 79.4, 105.66, 9.16, 16.18, and 15.6 per positive crab, respectively, and 11.12, 7.87, 0.58, 0.69, and 0.85 per gram of crab, respectively. All the metacercariae were identical to those of P. westermani. Adult worms and eggs of P. westermani were found in both reservoir hosts of domestic cats and dogs infected artificially. By comparing the COI genes of five representative samples from each survey site with that of Paragonimus #AF219379.21, AF540958.1 from GenBank, we found out the homology to be 99%, 99%, 99%, 98%, and 99%, respectively. In addition, a comparison of the ITS2 gene sequences between the above five samples and Paragonimus #DQ836243.1, DQ351845.1, AB354217.1 from GenBank revealed 98%, 99%, 98%, 98%, and 98% gene homology, respectively.

CONCLUSION

Two ultra-high and three high endemic areas of P. westermani are discovered in Guangdong Province. No obvious differences were found among the types of P. westermani in the above five endemic areas.

[Investigation on spread and hazards of human parasites in Qushui Village, Suixi County, Zhanjiang City]

OBJECTIVE

To understand the transmission of human parasites in Qushui Village, Yangqing Town, Suixi County, Zhanjing City, Guangdong Province.

METHODS

The direct stool smear, floatation, Kato-Katz technique, and hookworm larva culture were used for the parasite infections. The questionnaire survey was applied for the hazards of parasites. The dissections on rats and snails were used for Angiostrongylus cantonensis infection.

RESULTS

Five parasites were found and the total infection rate was 10.75%. The infection rates of hookworm (Necator americanus), Ascaris lumbricoides and Trichuris trichiura were 6.07%, 1.87% and 1.87%, respectively, and the infection rates of Enterobius vermicularis and Tyroglyrhus farinae were both 0.47%. The infections were not correlated with the career and age but preferred to males. The densities of infections were slight. The rate of dermatitis caused by hookworm larvae was 69.23%. The infection rates of Angiostrongylus cantonensis were 16.66%, 13.04% and 10.00%, respectively in rats, Achatina fulica and Ampularum crossean.

CONCLUSION

The main species of human parasites are nematodes, with hookworm predominately, in Qushui Village, Suixi County. This area is the natural foci of Angiostrongylus cantonensis.

Rapid detection of H5 avian influenza virus by TaqMan-MGB real-time RT-PCR

Aims:  Real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) assay based on a TaqMan‐minor groove binder (MGB) probe was developed for the rapid detection of avian influenza virus subtype H5.

Methods and Results:  Conserved regions in the haemagglutinin genes of avian influenza viruses subtype H5 served as targets for the primers and TaqMan‐MGB probe design. Concentrations of primers and probe were optimized to improve the sensitivity and specificity of the reactions. A plasmid containing the haemagglutinin gene was constructed and in vitro transcribed for a quantitative assay of copy numbers of the target gene. The results revealed that the optimal concentration of primers and probe was 640 and 480 nmol l⁻¹, respectively. The threshold of 100 copies of target molecules could be detected. The linear range for detection was determined as 10² to 10⁸ molecules in reaction.

Conclusions:  It took less than 3 h to complete the detection from viral RNA extraction, with good sensitivity and repeatability.

Significance and Impact of the Study:  Real‐time RT‐PCR assay with MGB probe was an effective means for quick and quantitative laboratory detection and monitoring of H5 avian influenza viruses.

Phosphatidylinositol-3-OH Kinase (PI3K)/AKT2, activated in breast cancer, regulates and is induced by estrogen receptor alpha (ERalpha) via interaction between ERalpha and PI3K

We have shown previously that the AKT2 pathway is essential for cell survival and important in malignant transformation. In this study, we demonstrate elevated kinase levels of AKT2 and phosphatidylinositol-3-OH kinase (PI3K) in 32 of 80 primary breast carcinomas. The majority of the cases with the activation are estrogen receptor alpha (ERalpha) positive, which prompted us to examine whether AKT2 regulates ERalpha activity. We found that constitutively activated AKT2 or AKT2 activated by epidermal growth factor or insulin-like growth factor-1 promotes the transcriptional activity of ERalpha. This effect occurred in the absence or presence of estrogen. Activated AKT2 phosphorylates ERalpha in vitro and in vivo, but it does not phosphorylate a mutant ERalpha in which ser-167 was replaced by Ala. The PI3K inhibitor, wortmannin, abolishes both the phosphorylation and transcriptional activity of ERalpha induced by AKT2. However, AKT2-induced ERalpha activity was not inhibited by tamoxifen but was completely abolished by ICI 164,384, implicating that AKT2-activated ERalpha contributes to tamoxifen resistance. Moreover, we found that ERalpha binds to the p85alpha regulatory subunit of PI3K in the absence or presence of estradiol in epithelial cells and subsequently activates PI3K/AKT2, suggesting ERalpha regulation of PI3K/AKT2 through a nontranscriptional and ligand-independent mechanism. These data indicate that regulation between the ERalpha and PI3K/AKT2 pathway (ERalpha-PI3K/AKT2-ERalpha) may play an important role in pathogenesis of human breast cancer and could contribute to ligand-independent breast cancer cell growth.

[The development of a competency-based clinical performance examination model in maternity nursing for BSN graduates]

The purpose of the study was to establish a competency-based clinical performance examination model in maternity nursing for baccalaureate students. Action research was the main research methodology used in the study. A committee, consisting of nursing faculty, students and experienced obstetric nurses, was established to develop the model. Based on intensive literature reviews and standards of nursing practice in Taiwan, the first draft of the model, including the content and process, was created by the committee. The draft then was revised twice after expert review and pilot testing. The revised version of the model was formally implemented into the curriculum to examine the competencies of forty-one BSN students at the end of the perinatal nursing course. Responses from students, clinical examiners, clinical staff and clients were all gathered and integrated to refine the model. The model has content, expert and discriminative validity. The reliability of the model was proven by the high consistency in administration and scoring of the model among clinical examiners.

Human hepatocellular carcinoma is characterized by a highly consistent pattern of genomic imbalances, including frequent loss of 16q23.1-24.1

Comparative genomic hybridization (CGH) analysis was used to identify chromosomal imbalances in 52 human primary hepatocellular carcinomas (HCCs). The most prominent changes were gains of part or all of chromosome arms 8q (83% of cases) and 1q (73%) and loss of 16q (63%). Other commonly overrepresented sites were 5p, 7q, and Xq. Recurrent sites of DNA sequence amplification included 8q23--24 (five cases) and 11q13--14 (four cases). Other frequently underrepresented sites were 4q, 8p, 16p, and 17p. Taken collectively, these findings and data from other CGH studies of HCCs define a subset of chromosome segments that are consistently over- or underrepresented and highlight sites of putative oncogenes and tumor suppressor genes, respectively, involved in hepatocellular oncogenesis. Loss of heterozygosity analysis with a panel of polymorphic microsatellite markers distributed along 16q defined a minimal region of chromosomal loss at 16q23.1--24.1, suggesting that this region harbors a tumor suppressor gene whose loss/inactivation may contribute to the pathogenesis of many HCCs.

[Study on the relationship between microvascular density and prognosis in laryngeal cancer]

OBJECTIVE

To study the relationship between the microvascular density(MVD) and the prognosis in laryngeal cancer.

METHOD

Microvessel quantitation in 31 cases of laryngeal cancer was done with factor VIII-related antibody and SABC method.

RESULT

The quantitation of microvessels in laryngeal cancer were negative of histologic grade and type, but were significantly different (P < 0.05) between metastasis (10.23 +/- 0.78) and without metastasis(6.38 +/- 0.33) two years after operation.

CONCLUSION

The angiogenesis of laryngeal cancer is correlated with the lymph node metastasis and prognosis.

The suppression effect of light rare earth elements on proliferation of two cancer cell lines

To study the suppression effect of light rare earth elements (RE) on proliferation of two cancer cell lines. Two cancer cell lines PAMC82 and K562 were used to examine their colony-forming ability in soft agar, microtubule structure, calmodulin levels and regulation of some gene expressions by Northern blot analysis with and without treatment by RE. The results showed that on soft agar culture the colony-forming ability of human gastric cancer cell line PAMC82 treated by RE chloride decreased and the PAMC82 cell microtubule abnormal structure became normal. The calmodulin (CaM) levels decreased in human leukemia cells (K562) treated with cerium chloride and neodymium chloride. The Northern blot analysis revealed marked up-regulation of p53, p16(MTS1), p21 (WAF1) gene expressions in PAMC82 cells treated with lanthanum chloride and cerium chloride, as compared to control PAMC82 cells. The light rare earth elements studied have certain suppression effects on proliferation of cancer cells. This effect might be related to the decrease of calmodulin and up-regulation of some gene expressions in cancer cells.

[Effects of total flavones of metasequosia on left ventricular hypertrophy due to pressure overload in rats]

OBJECTIVE

To determine the preventive and regressive effects of total flavones of metasequosia (TFM) on left ventricular hypertrophy in rats.

METHOD

Left ventricular hypertrophy was inducedin by partial ligation of abdominal aorta. The rats were given ig TFM(4, 40, 400 mg.kg-1.d-1) for six weeks.

RESULT

TFM markedly reduced the HW/BW, LVW/BW, myofibril diameter and Ca2+ content in left ventricles but the systolic blood pressure (SBP) in rats wasn't obviously influenced.

CONCLUSION

TFM can prevent and reverse the left ventricular hypertrophy due to pressure overload in rats. The mechanism may be related to its calcium antagonistic properties.

Depth of anesthesia estimation and control

A fully automated system was developed for the depth of anesthesia estimation and control with the intravenous anesthetic, Propofol. The system determines the anesthesia depth by assessing the characteristics of the mid-latency auditory evoked potentials (MLAEP). The discrete time wavelet transformation was used for compacting the MLAEP which localizes the time and the frequency of the waveform. Feature reduction utilizing step discriminant analysis selected those wavelet coefficients which best distinguish the waveforms of those responders from the nonresponders. A total of four features chosen by such analysis coupled with the Propofol effect-site concentration were used to train a four-layer artificial neural network for classifying between the responders and the nonresponders. The Propofol is delivered by a mechanical syringe infusion pump controlled by Stanpump which also estimates the Propofol effect-site and plasma concentrations using a three-compartment pharmacokinetic model with the Tackley parameter set. In the animal experiments on dogs, the system achieved a 89.2% accuracy rate for classifying anesthesia depth. This result was further improved when running in real-time with a confidence level estimator which evaluates the reliability of each neural network output. The anesthesia level is adjusted by scheduled incrementation and a fuzzy-logic based controller which assesses the mean arterial pressure and/or the heart rate for decrementation as necessary. Various safety mechanisms are implemented to safeguard the patient from erratic controller actions caused by external disturbances. This system completed with a friendly interface has shown satisfactory performance in estimating and controlling the depth of anesthesia.

Decreased accumulation and dephosphorylation of the mitosis-specific form of nucleophosmin/B23 in staurosporine-induced chromosome decondensation

Nucleophosmin/B23 is highly phosphorylated by cdc2 kinase during mitosis, and this phosphorylation most probably has a role in initiating and controlling the entry of cells into mitosis [Peter, Nakagawa, Doree, Labbe and Nigg (1990) Cell 60, 791-801]. In the present study, the protein kinase inhibitor staurosporine has been used to examine possible changes in nucleophosmin/B23 at mitosis in HeLa cells. Addition of staurosporine to HeLa cells already arrested at mitosis by nocodazole causes: (i) decreased accumulation of the mitosis-specific form of nucleophosmin/B23, (ii) dephosphorylation of nucleophosmin/ B23, (iii) redistribution of nucleophosmin/B23 to the cytosol, and (iv) concomitant decondensation of chromosomes. These results suggest that the mitosis-specific phosphorylated form of nucleophosmin/B23 may play a role in maintaining mitotic chromosomes in their condensed state.

The synthesis and biological activities of oligodeoxynucleotides that are covalently linked to psoralen at their 5' ends

Four oligodeoxynucleotides (15-mers), designated 13 through 16, and the corresponding conjugates, designated 17 through 20, in which psoralen was covalently linked to the 5' end of each oligonucleotide were synthesized. Compounds 16 and 20 contained a sequence that was complementary to part of the first four codons and the upstream sequence close to the ribosome-binding site of c-Ha-ras mRNA. Compounds 16 and 20 inhibited the growth of cells that had been transformed by the c-Ha-ras plasmid, with accompanying suppression of the expression of the activated c-Ha-ras oncogene. The antisense oligonucleotides 16 and 20 also appeared to cause partial reversion of the major phenotypic characteristics of transformed cells, which included inhibition of anchorage-independent growth. Compound 20, which contained psoralen, was a more efficient inhibitor of the growth of transformed cells than compound 16 without psoralen, a result that suggests psoralen might have increased the ability of the oligodeoxynucleotides to enter the cells.

Long-term exposure to chromium(VI) oxide leads to defects in sulfate transport system in Chinese hamster ovary cells

Chromium(VI) resistant Chinese hamster ovary (CHO) cell lines were established in this study by exposing parental CHO-K1 cells to sequential increases in CrO3 concentration. The final concentration of CrO3 used for selection was 7 microM for Cr7 and 16 microM for Cr16 cells. Cr16-1 was a subclone derived from Cr16 cells. Next, these resistant cells were cultured in media without CrO3 for more than 6 months. The resistance of these cells to CrO3 was determined by colony-forming ability following a 24-h treatment. The LD50 of CrO3 for chromium(VI) resistant cells was at least 25-fold higher than that of the parental cells. The cellular growth rate, chromosome number, and the hprt mutation frequency of these chromium(VI) resistant cells were quite similar to their parental cells. The glutathione level, glutathione S-transferase, catalase activity, and metallothionine mRNA level in Cr7 and Cr16-1 cells were not significantly different from their parental cells. Furthermore, Cr16-1 cells were as sensitive as CHO-K1 cells to free-radical generating agents, including hydrogen peroxide, nickel chloride, and methanesulfonate methyl ester, and emetine, i.e., a protein synthesis inhibitor. The uptake of chromium(VI) and the remaining amount of this metal in these resistant and the parental cell lines were assayed by atomic absorption spectrophotometry. Experimental results indicated that a vastly smaller amount of CrO3 entered the resistant cell lines than their parental cells did. A comparison was made of the sulfate uptake abilities of CHO-K1 and chromium(VI) resistant cell lines. These results revealed that the uptake of sulfate anion was substantially reduced in Cr7 and Cr16-1 cells. Extracellular chloride reduced sulfate uptake in CHO-K1 but not in Cr16-1 cells. Therefore, the major causative for chromium(VI) resistance in these resistant cells could possibly be due to the defects in SO4(2-)/C1- transport system for uptake chromium(VI).

[Amplification of oncogenes HER2, mdm-2 and myc in breast cancer determined by modified competitive PCR]

The amplification of oncogenes HER2, mdm-2 and myc was determined with a modified competitive PCR. The HER2, mdm-2 and myc genes were found to amplify in 5, 6 and 6 out of 15 patients with breast cancer respectively. The amplification of HER2 and mdm-2 correlated with advanced tumors and lymph node involvement respectively, indicating that the amplification of the oncogenes is a useful indicator for the prognosis of patients with breast cancer and for the study of the biological behaviors of tumors. This modified non-radioactive competitive PCR is simple to handle (even for DNA samples with low quantity and low quality), and accurate for measuring the copy numbers of genes.

Murine cytomegalovirus-associated pneumonitis in the lungs free of the virus

At 4 wk after intraperitoneal inoculation of murine cytomegalovirus (MCMV) in adult BALB/c mice, MCMV remained detectable only in the salivary glands. When T cells of these mice were activated by a single injection of anti-CD3 epsilon monoclonal antibody, mice died of interstitial pneumonitis at 24-48 h after injection, accompanied by elevation of serum levels of TNF-alpha and IFN-gamma. However, MCMV remained undetectable in the lungs during the period. Simultaneous injection of cyclosporin A reduced such effects of anti-CD3. In conclusion, although the presence of MCMV in the host may be required, MCMV-associated pneumonitis is not mediated by virus in the lung but probably by the cytokines released from T cells, of which responsiveness to stimulation via CD3 molecule has been presumably modified by MCMV infection.

Priming of immature thymocytes to CD3-mediated apoptosis by infection with murine cytomegalovirus

Cytomegalovirus (CMV) causes severe clinical manifestations in immunocompromised hosts; however, it remains unclear whether the virus itself is a cause of immunosuppression or whether it is involved as an opportunistic bystander pathogen. This study was performed to elucidate the effect of CMV infection on the host's immune system. The double-positive thymocytes of BALB/c mice inoculated with a sublethal dose of murine CMV (MCMV) were extensively depleted by a 10-micrograms amount of anti-CD3 monoclonal antibody, while such an amount was unable to induce any apparent elimination of thymocytes in noninfected mice. In immature thymocytes of infected hosts, a markedly high level of susceptibility to apoptosis induction was found on treatment with anti-CD3 monoclonal antibody. Analysis of the signal transduction pathway of such double-positive thymocytes demonstrated a profound elevation of the intracellular Ca2+ level after anti-CD3 stimulation, implying that this aberrant mobilization of Ca2+ plays a crucial role in the signaling pathway leading these cells to an extensive apoptosis. Examination of the thymus by PCR was able to detect a low copy number of MCMV DNAs in thymic stromal cells but none at all in thymocytes. Therefore, it is suggested that a mechanism which is not associated with virus replication within the cells exerts a critical effect on rendering the thymocytes highly apoptosis sensitive in hosts infected with MCMV.