Efficacy evaluation of a bivalent subunit vaccine against classical swine fever virus and porcine circovirus type 2

Classical swine fever virus (CSFV) and porcine circovirus type 2 (PCV2) are two of the most devastating and economically significant pathogens affecting pig populations worldwide. Administration of a combination of vaccines against swine pathogens has been demonstrated to be as efficacious as the administration of single vaccines. In this study, we developed and tested a novel bivalent subunit vaccine against CSFV and PCV2. The safety and efficacy of this vaccine were demonstrated in mice and specific pathogen-free (SPF) piglets. In addition to investigating the serological responses after immunization, challenge studies with both viruses were also conducted. The results showed that this CSFV/PCV2 bivalent vaccine elicited a high level of neutralizing antibodies against both viruses and provided protection in challenge studies. In conclusion, the CSFV/PCV2 bivalent vaccine is safe and effective against CSFV or PCV2 challenge.

Effects of Composition Type and Activator on Fly Ash-Based Alkali Activated Materials

The compressive strengths of fly ash-based alkali-activated materials (AAM), produced using various activators of only sodium hydroxide, were measured. Fly ash-based AAM specimens, produced by mixing different kinds of fly ash and ground granulated blast-furnace slag (GGBFs) with an activator containing only sodium hydroxide, were cured at ambient temperature, and then placed in air for different numbers of days. The short- and long-term compressive strengths and shrinkage of fly ash-based AAM were measured and compared to one another. The effects of type of fly ash, alkali-equivalent content, GGBFs replace percentage, and ages on the compressive strengths and shrinkage of fly ash-based AAM were investigated. Even when different fly ash was used as the raw material for AAM, a similar compressive strength can be achieved by alkali-equivalent content, GGBFs replaces percentage. However, the performance of shrinkage due to different types of fly ash differed significantly.

[CCAAT/enhancer binding protein δ inhibits invasion and metastasis of liver cancer by regulating M1 type macrophages polarization]

Objective: To explore the regulation of macrophage polarization and its effects on liver cancer invasion, metastasis and apoptosis by CCAAT/enhancer binding protein δ (CEBPD). Methods: THP-1 stable transfected cells with knockdown CEBPD (shCEBPD) and negative control shNC were constructed by lentviral transfection technique. THP-1 transfected cells were induced into macrophages, lipopolysaccharide (LPS) and interferon γ(IFNγ) by phorbol 12-tetradecanoate 13-acetate (PMA), and then the polarized macrophages were further induced to M1 type. The quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect M1 type macrophage related interleukin 1β (IL-1β) genes, IL-6, tumor necrosis factor α (TNFα), and inducible nitric oxide synthase (iNOS) mRNA expression level. Flow cytometry was used to detect M1 macrophage-specific surface marker CD80 expression levels. M1-induced macrophages were co-cultured with liver cancer MHCC97H cells using Transwell non-contact small sized co-culture dishes. MHCC97H cells invasion and metastasis were detected by Transwell and scratch assay under co-culture conditions, and the MHCC97H cells apoptosis was detected by flow cytometry. Results: The mRNA expression levels of M1 macrophage marker genes iNOS, TNFα, IL-6 and IL-1β in THP-1 derived macrophages were decreased after CEBPD knockdown. M1 macrophage-specific surface marker CD80 expression levels were decreased (23.7% ± 2.1% and 62.5% ± 2.0%, t = 9.58, P < 0.05). THP-1 were co-cultured with MHCC97H in shCEBPD and shNC group, respectively. Compared with shNC group, the invasion [(158.0 ± 3.5) and (75.0 ± 4.5), t = 39.87, P < 0.01] and metastatic ability (54.6% ± 1.5% and 24.3% ± 1.0%, P < 0.01) of MHCC97H cells co-cultured in shCEBPD group were stronger and the apoptosis rate was reduced [(9.4% ± 1.0%) vs. (23.7% ± 1.2%), t = 12.68, P < 0.01]. Conclusion: CEBPD can inhibit the invasion and metastasis and increase the apoptosis by amplifying M1 type macrophages polarization in liver cancer cells.

Geometry-Based Camera Calibration Using Closed-Form Solution of Principal Line

Camera calibration is a crucial prerequisite in many applications of computer vision. In this paper, a new geometry-based camera calibration technique is proposed, which resolves two main issues associated with the widely used Zhang's method: (i) the lack of guidelines to avoid outliers in the computation and (ii) the assumption of fixed camera focal length. The proposed approach is based on the closed-form solution of principal lines with their intersection being the principal point while each principal line can concisely represent relative orientation/position (up to one degree of freedom for both) between a special pair of coordinate systems of image plane and calibration pattern. With such analytically tractable image features, computations associated with the calibration are greatly simplified, while the guidelines in (i) can be established intuitively. Experimental results for synthetic and real data show that the proposed approach does compare favorably with Zhang's method, in terms of correctness, robustness, and flexibility, and addresses issues (i) and (ii) satisfactorily.

Clincopathological characteristics and treatment outcomes of oral leukoplakia by carbon dioxide laser excision in the elderly patients

Background

Older age is one of the factors associated with malignant transformation of oral leukoplakia (OL). The purpose of this study is to analyze the clincopathological features and treatment outcomes of OL in the elderly patients.

Methods

The demographic data and histopathological results of the patients (age ≥ 65) who received carbon dioxide laser surgery for OL from 2002 to 2017 were analyzed statistically.

Results

There were 53 males and 16 females, with a mean age 71.2 ± 4.9. The follow‐up time was 42.5 ± 35.2 months. In the univariate analysis, morphology, pathology, and area were found to be factors associated with postoperative recurrence. Among these factors, pathology and area were the independent predictive factors for recurrence in the multivariate logistic regression model. Malignant transformation occurred in 8 of 69 patients (11.6%).

Conclusions

The pathological high‐risk dysplasia and area of OL were the two prognostic factors for postoperative recurrence.

Stimulation of Proliferation and Migration of Mouse Macrophages by Type B CpG-ODNs Is F-Spondin and IL-1Ra Dependent

Macrophage proliferation and migration are important for many facets of immune response. Here we showed that stimulation of macrophages with type B CpG oligodeoxynucleotides (CpG-B ODNs) such as CpG-ODN 1668 increased the production of anti-inflammatory cytokine interleukin 1 receptor antagonist (IL-1Ra) in a TLR9- and MyD88-dependent manner. The CpG-B ODNs-induced IL-1Ra increased macrophage migration and promoted macrophage proliferation by down-regulating the expression of a cell cycle negative regulator, p27 to increase cell population in the S phase. The induction of IL-1Ra by CpG-B ODNs was F-spondin dependent. Knockdown of F-spondin and IL-1Ra decreased CpG-B ODNs-induced macrophage migration whereas overexpression of IL-1Ra increased migration of those cells. These findings demonstrated novel roles for F-spondin and IL-1Ra in CpG-B ODNs-mediated cell proliferation and migration of macrophages.

Clinical characteristics of narrow-band imaging of oral erythroplakia and its correlation with pathology

Background

To analyze the clinical application of endoscope with narrow-band imaging (NBI) system in detecting high-grade dysplasia, carcinoma in situ, and carcinoma in oral erythroplakia.

Methods

The demographic, histopathological data, and NBI vasculature architectures of patients receiving surgical intervention for oral erythroplakia were retrospectively reviewed and analyzed statistically.

Results

A total of 72 patients, including 66 males and 6 females, with mean age of 54.6 ± 11.2 years, were enrolled. The odds ratio of detecting high-grade dysplasia, carcinoma in situ, and carcinoma by twisted elongated morphology and destructive pattern of intraepithelial microvasculature was 15.46 (confidence interval 95 %: 3.81–72.84), and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 80.95 %, 78.43 %, 60.71 %, 90.91 %, and 79.17 %, respectively, which were significantly better than other two established NBI criteria (p < 0.001).

Conclusions

Twisted, elongated, and destructive patterns of intraepithelial papillary capillary loop of NBI images are indicators for high-grade dysplasia, carcinoma in situ, and invasive carcinoma in oral erythroplakia.

Outcome of excision of oral erythroplakia

Oral erythroplakia is a precancerous lesion with high malignant potential, and resection is the recommended treatment. We designed a retrospective study to analyse the outcome of treatment in patients who had operations for oral erythroplakia. A total of 84 patients (74 men and 10 women, mean (SD) age 54 (12) years, range 29-83) were enrolled. Histopathologically the diagnoses were invasive carcinoma (n=3), dysplasia/carcinoma in situ (n=61), and squamous hyperplasia (n=20), and all patients were treated by carbon dioxide laser excision. There was no postoperative malignant transformation, but invasive carcinoma found after initial excision (n=3) was treated by further radical excision. The mean (SD) follow-up period was 46 (29) months (range 1-124), The postoperative recurrent rate was 14/84 (16.7%). The area of oral erythroplakia was the only factor associated with postoperative recurrence on univariate analysis, and was also the only independent factor that predicted postoperative recurrence in multivariate logistic regression analysis. An area exceeding 80 mm2 had the best predictive value (sensitivity=0.71, specificity=0.67) with a 5.1 times increased risk (odds ratio=5.1, CI 95% 1.45 to 18.05, p=0.01) of recurrence. Laser excision is effective for oral erythroplakia that is still confined to dysplasia of any degree, with low morbidity. The area of oral erythroplakia is a predictive factor for postoperative recurrence.

Abstract A100: Fibrillar human serum albumin suppresses ovarian cancer metastasis by targeting β1 integrin and its downstream FAK signaling pathways

Due to the high mortality caused by frequent relapse and metastasis in patients with ovarian cancer, advances in treatment remain necessary. In this study, we developed a chromatographical process which converted native protein human serum albumin (HSA) into a water-soluble nano-fibrillar protein structure and aimed to explore the potential inhibitory effect of fibrillar HSA (F-HSA) on ovarian tumor metastasis. Transwell migration assay, western blotting and gelatin zymography were used to investigate the effects of F-HSA in vitro. Its effects in vivo were evaluated in orthotopic and metastatic xenograft mouse models established using an SKOV3 ovarian cancer cell line that stably expressed green fluorescent protein and luciferase. The fibrillar structure of converted HSA was verified by transmission electron microscopy and Thioflavin T (ThT) fluorescence assay. Treatment with F-HSA decreased the viability, migration and invasion of several ovarian cancer cell lines in vitro. F-HSA bound to β1 integrin receptor to increase PTEN phosphorylation and decrease phosphorylation of FAK and Akt. The inhibitory effect of F-HSA on invasive ability of SKOV3 cells was associated with decreases in phosphorylation of Raf and Erk as well as changes in Crk phosphorylation leading to down-regulation of Rac and MMP2 activities. Orthotopic and metastatic xenograft mouse models showed that F-HSA treatment suppressed tumor growth and metastasis and prolonged survival of SKOV3-bearing mice. These results suggest that F-HSA may have great potential for development as a novel therapeutic agent for metastatic and drug-resistant ovarian cancer.

Citation Format: Tai-An Chen, Shao-Wen Hung, Yu-Ching Chang, Chih-Yuan Chen, Hsin-Ying Hsieh, Chi-Ming Liang, Shu-Mei Liang. Fibrillar human serum albumin suppresses ovarian cancer metastasis by targeting β1 integrin and its downstream FAK signaling pathways. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr A100.

Recombinant viral protein VP1 suppresses HER-2 expression and migration/metastasis of breast cancer

Breast cancer is one of the most common cancers in women worldwide and metastasis is the major cause of breast cancer death. Development of new therapeutic agents for inhibiting breast cancer metastasis is therefore an urgent need. We previously demonstrated that recombinant DNA-derived viral capsid protein VP1 (rVP1) of foot-and-mouth disease virus-induced apoptosis of MCF-7 breast cancer cells in vitro. Here, we investigated whether rVP1 exhibits any inhibitory effects on migration/metastasis and human epidermal growth factor receptor 2 (HER-2), a well-known biomarker for poor prognosis of breast cancer. The effects of rVP1 on cancer cell migration/invasion and metastasis were evaluated using Transwell migration assay and animal cancer models of metastasis. Western blotting, RT-PCR, flow cytometry, immunohistochemistry, and immunofluorescence staining techniques were used to investigate the effects of rVP1 on HER-2 and signal transduction mediators. Non-cytotoxic concentrations of rVP1-induced mesenchymal-epithelial transition and significantly suppressed AP-2α and HER-2 expression as well as the migration and invasion of a variety of breast cancer cell lines in a β1-integrin-dependent manner in vitro. Gross and histopathologic examinations showed that rVP1 also suppressed metastasis of several breast cancer cell lines, including HER-2-overexpressing SK-BR-3 and BT-474 cells to lung, liver, or peripheral lymph node in orthotopic allograft/xenograft murine models. In addition, rVP1 significantly prolonged survival in breast cancer-bearing mice. Notably, no apparent side effects of rVP1 were detected, as shown by normal complete blood count levels and serum biochemistry profiles, including AST, ALT, BUN, and creatine. This study demonstrates that rVP1 suppresses the migration, invasion, and metastasis of breast cancer cells via binding to β1 integrin receptor and down-regulation of AP-2α and HER-2 expression. The effectiveness of rVP1 on inhibiting migration/metastasis of breast cancer and HER-2 expression suggests that it may be suitable for serving as potential therapeutics for metastatic breast cancer particularly HER-2-overexpressing cancer.

3'poly-G-tailed ODNs inhibit F-spondin to induce cell death and neurite retraction in rat embryonic neurons

The effects and mechanism of action of oligodeoxyribonucleotides containing CpG motif (CpG-ODNs) on neuron cells are largely unexamined. Here, we found that CpG-A ODNs but not other types of CpG-ODNs induced neurite retraction and cell apoptosis of rat embryonic neurons in a TLR9-independent manner. These effects of CpG-A ODNs were primarily due to the poly-guanosine at the 3' terminus (3'G-ODNs). Pull-down analysis showed that 3'G-ODNs associated with transcription factor Y-BOX1 (YB-1) to facilitate the translocation of YB-1 into the nucleus via the nuclear localizing sequence of YB-1. YB-1 then interacted with the promoter of F-spondin directly at -45 and -1,375 sites as demonstrated by chromatin immunoprecipitation (ChIP) analysis. Binding of YB-1 to F-spondin promoter resulted in downregulation of F-spondin expression. Overexpression of F-spondin rescued the cell death and neurite retraction induced by 3'G-ODNs in embryonic neuron cells. Taken together, these findings suggest that 3'G-ODNs enhance nucleus YB-1 to inhibit F-spondin leading to cell death and neurite retraction of embryonic neuron cells.

Clinical appraisal of endoscopy with narrow-band imaging system in the evaluation and management of homogeneous oral leukoplakia

PURPOSE

To evaluate the clinical usefulness of endoscopy with a narrow-band imaging (NBI) system for the evaluation and management of homogeneous oral leukoplakia.

METHODS

The chart records, morphology of vascular architecture of NBI, and histopathology of patients with homogeneous leukoplakia were retrospectively reviewed and analyzed.

RESULTS

A total of 160 patients, with an average age of 50.96 ± 10.25 years, were enrolled. In 35 cases of thin leukoplakia, only intraepithelium papillary capillary loop (IPCL) type I was shown by NBI, and only squamous hyperplasia was revealed pathologically. In 125 cases of thick leukoplakia, IPCL type I was found in 94, IPCL type II in 29, and IPCL type III in 2. The Kendall rank correlation between pathology and NBI images was significant (p < 0.0001).

CONCLUSIONS

The dichotomous classification of homogeneous leukoplakia by NBI is meaningful, and endoscopy with the NBI system is a promising tool for the evaluation and management of homogeneous oral leukoplakia.

Use of endoscopy with narrow-band imaging system in evaluating oral leukoplakia

BACKGROUND

The purpose of this study was to analyze the relationship between clinical features of oral leukoplakia using endoscopy with broadband white light, narrow-band imaging (NBI) illumination, and histopathology, and to discuss the clinical relevance of the NBI system.

METHODS

Clinicopathologic data of patients receiving biopsy or excision after endoscopic examination for leukoplakia from April 2009 to December 2010 were reviewed and analyzed statistically.

RESULTS

A total 154 patients, 130 men and 24 women (average age, 52.60 ± 10.86 years) were enrolled. The correlation between intraepithelium papillary capillary loop (IPCL) classification and stepwise increased severity of pathology (Pearson's r = .88, R(2) = 0.78) was significantly better than that of broadband white light images (p < .001).

CONCLUSIONS

Flexible endoscopy can enhance detailed inspection of oral cavity mucosa and can be a powerful tool for examining oral leukoplakia. The IPCL patterns shown by NBI system can be helpful in detecting oral leukoplakia with higher grade dysplasia or invasive carcinoma.

Recombinant VP1, an Akt inhibitor, suppresses progression of hepatocellular carcinoma by inducing apoptosis and modulation of CCL2 production

Background

The application of viral elements in tumor therapy is one facet of cancer research. Recombinant capsid protein VP1 (rVP1) of foot-and-mouth disease virus has previously been demonstrated to induce apoptosis in cancer cell lines. Here, we aim to further investigate its apoptotic mechanism and possible anti-metastatic effect in murine models of hepatocellular carcinoma (HCC), one of the most common human cancers worldwide.

Methodology/Principal Findings

Treatment with rVP1 inhibited cell proliferation in two murine HCC cell lines, BNL and Hepa1-6, with IC₅₀ values in the range of 0.1–0.2 µM. rVP1 also induced apoptosis in these cells, which was mediated by Akt deactivation and dissociation of Ku70-Bax, and resulted in conformational changes and mitochondrial translocation of Bax, leading to the activation of caspases-9, -3 and -7. Treatment with 0.025 µM rVP1, which did not affect the viability of normal hepatocytes, suppressed cell migration and invasion via attenuating CCL2 production. The production of CCL2 was modulated by Akt-dependent NF-κB activation that was decreased after rVP1 treatment. The in vivo antitumor effects of rVP1 were assessed in both subcutaneous and orthotopic mouse models of HCC in immune-competent BALB/c mice. Intratumoral delivery of rVP1 inhibited subcutaneous tumor growth as a result of increased apoptosis. Intravenous administration of rVP1 in an orthotopic HCC model suppressed tumor growth, inhibited intra-hepatic metastasis, and prolonged survival. Furthermore, a decrease in the serum level of CCL2 was observed in rVP1-treated mice.

Conclusions/Significance

The data presented herein suggest that, via inhibiting Akt phosphorylation, rVP1 suppresses the growth, migration, and invasion of murine HCC cells by inducing apoptosis and attenuating CCL2 production both in vitro and in vivo. Recombinant protein VP1 thus has the potential to be developed as a new therapeutic agent for HCC.

Postoperative recurrence as an associated factor of malignant transformation of oral dysplastic leukoplakia

PURPOSE

To evaluate the clinically associated factors of malignant transformation in patients who received laser surgery for oral dysplastic leukoplakia.

PROCEDURES

The clinicopathological data of patients receiving laser surgery for dysplastic leukoplakia from 2002 to 2008 and HPV genomic DNA extracted from paraffin-embedded specimens were analyzed statistically.

RESULTS

A total 114 patients, 90 males and 24 females with an average age of 49.7 ± 12.2 years were enrolled. The follow-up period ranged from 1.07 to 7.43 years (mean 3.4 ± 1.3 years). Thirteen cases had malignant transformation (11.4%). Multiple-focus lesions, non-homogeneous leukoplakia, high-grade dysplasia and recurrence after laser treatment were significant factors in univariate analysis. Multivariate analysis showed that recurrence (relative risk = 9.40) was the independent prognostic factor for malignant transformation.

CONCLUSIONS

Recurrence after laser treatment is an independent prognostic factor predicting malignant transformation of dysplastic oral leukoplakia.

Corn stunt spiroplasma: isolation, cultivation, and proof of pathogenicity

A spiroplasma isolated from corn infected with corn stunt disease has been successfully cultivated in vitro. Acid formation was associated with its growth in liquid medium, and fried egg-shaped or granulated colonies developed on solid agar medium. Healthy leafhopper vectors injected with or allowed to feed on isolates from various serial passages through liquid medium were able to transmit the corn stunt agent to healthy corn plants, inducing typical corn stunt disease in the plants. The spiroplasma was reisolated and cultivated from such diseased plants and was indistinguishable morphologically from the original isolates. These results provide the first definite proof that the corn stunt disease is caused by the corn stunt spiroplasma.

High-dose bisacodyl plus water lavage compared with oral sodium phosphate as bowel preparation for outpatient colonoscopy

BACKGROUND

The aim of this prospective study was to compare the efficacy and patient compliance of an oral high dose of bisacodyl plus water lavage and oral sodium phosphate in adults undergoing elective colonoscopy.

METHODS

A total of 276 patients were randomized to receive an oral high-dose bisacodyl preparation (6 tablets of 5mg bisacodyl) plus water lavage (2 L of water) or an oral sodium phosphate (NaP) preparation (90 mL in divided doses). All endoscopic procedures were conducted in the afternoon. The endoscopist was blinded to the preparation the patient had received and graded the quality of colon cleansing as excellent, good, fair, poor, or failed. Patients' demographic data, indications for the procedure, and colonoscopic findings were recorded and compared.

RESULTS

Significantly improved (p < 0.001) bowel preparation after NaP compared with bisacodyl plus water lavage was reported. The completion rate of colonoscopy was significantly lower (p < 0.001) in the bisacodyl group (70.6%) than in the NaP group (92.9%). The detection of polyps was significantly increased (p = 0.017) in the NaP group (43.1%) compared with the bisacodyl group (27.1%). A procedural indication of constipation was an independent predictor of failed preparation in the bisacodyl group (odds ratio, 4.8; 95% confidence interval, 1.9-12.0; p < 0.001).

CONCLUSION

The quality of bowel preparation with oral NaP was better than that with bisacodyl plus water lavage.

Effect of intravenous albumin on endotoxin removal, cytokines, and nitric oxide production in patients with cirrhosis and spontaneous bacterial peritonitis

OBJECTIVE

In patients with cirrhosis and spontaneous bacterial peritonitis (SBP), the use of intravenous albumin has been shown to prevent deterioration of renal function and to decrease the mortality rate, but the mechanisms remain unclear. The purpose of this study was to characterize the mechanisms of action of albumin with the focus on endotoxin and cytokines.

MATERIAL AND METHODS

Thirty patients with SBP were divided into two groups. Group 1 received antibiotics and albumin infusion (20% 50 cc every day for 3 days) and Group 2 received antibiotic treatment only. Twenty-four cirrhotic patients with sterile ascites were enrolled in Group 3 and received albumin infusion (20% 50 cc every day for 3 days). Plasma and ascitic fluid concentrations of endotoxin, nitric oxide products (NOx), tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 were analyzed before and after treatments, respectively.

RESULTS

Combination therapy of albumin and antibiotics can significantly (p<0.01) reduce plasma levels of TNF-alpha and IL-6, and ascitic fluid levels of endotoxin, TNF-alpha and IL-6 in cirrhotic patients with SBP. Without the addition of albumin to an antibiotic regimen, the plasma and ascitic fluid levels of NOx increased significantly in patients with SBP (p=0.005 and p=0.004, respectively).

CONCLUSIONS

The results confirm that the beneficial effects of albumin are related to the reduction of the levels of TNF-alpha and NOx in both plasma and ascitic fluid. The infusion of albumin continuously for 3 days in addition to antibiotic treatment at the time of SBP detection is recommended as an effective therapy for patients with cirrhosis and SBP.

A randomized, controlled trial of banding ligation plus drug therapy versus drug therapy alone in the prevention of esophageal variceal rebleeding

BACKGROUND & AIMS

Both medications with beta-blockers and isosorbide-5-mononitrate and endoscopic variceal ligation have been proven plausible in the prevention of variceal rebleeding. However, the relative efficacy and safety of the combined treatment for preventing rebleeding remains unresolved.

METHODS

Patients with history of esophageal variceal bleeding were enrolled. Emergency ligation was performed in patients with acute variceal bleeding. After hemodynamic stability, eligible patients were randomized to either the Medication group, using nadolol plus isorsorbide-5-mononitrate, or the Combined group, receiving banding ligation in addition to medications. Patients in the two groups with rebleeding from esophageal varices were treated with band ligation. The end points were rebleeding from varices or death.

RESULTS

After a median follow up of 23 months, recurrent upper gastrointestinal bleeding developed in 51% in the Medication group and 38% in the Combined group (P = 0.21). Recurrent bleeding from esophageal varices occurred in 26 patients (43%) in the Medication group and in 16 patients (26%) in the Combined group (P = 0.07). Recurrent bleeding from gastroesophageal varices occurred in 48% of Medication group and 28% of Combined group (P = 0.05). The frequency of adverse effects and mortality rates were similar between both groups (P = 0.28).

CONCLUSIONS

Combined ligation with medications was marginally more effective than medication alone in the prevention of gastroesophageal variceal rebleeding with similar adverse effects and mortality.

Treatment of wide-based epiglottic cyst by microdebrider

Epiglottic cyst is not an unusual disease in the larynx. Although it is usually a benign lesion, airway problems may occur due to a large cyst. Surgical excision is usually the treatment of choice, with low recurrence. Because of the limited view and mobility of laryngoscopes, there is sometimes difficulty in the procedure of excision or marsupialization, especially in wide-based epiglottic cysts. The microdebrider has been widely used in treatment of otolaryngological diseases, and specialized blades were designed for laryngeal lesions. We report the use of a microdebrider for treatment of wide-based epiglottic cysts in six patients. The follow-up period ranged from five months to 62 months without recurrence. One hand-powered instrument provided a clear surgical field for precise removal of the cyst and synchronized suction, and increased mobility of the laryngoscope held in the other hand. In comparison to traditional microinstrumentation and carbon dioxide laser, the microdebrider offered a rapid and effective alternative in treatment of wide-based epiglottic cyst.

Improved survival in patients receiving medical therapy as compared with banding ligation for the prevention of esophageal variceal rebleeding

Both medical therapy and endoscopic variceal ligation (EVL) have proven to be comparable in the prevention of variceal rebleeding. However, the long-term results are still lacking. Our previous study enrolled 121 patients with history of esophageal variceal bleeding and randomized to receive EVL (EVL group, 60 patients) or drug therapy, nadolol plus isosorbide-5-mononitrate (N+I) (N+I group, 61 patients) to prevent variceal rebleeding. The EVL group received ligation regularly until variceal obliteration. The N+I group received N+I during the study period. Patients were followed for up to 8 years. After a median follow-up of 82 months, recurrent upper gastrointestinal bleeding developed in 28 patients (47%) in the EVL group and 49 patients (80%) in the N+I group (P = 0.001). Recurrent bleeding from esophageal varices occurred in 18 patients (30%) in the EVL group and 39 patients (64%) in the N+I group. The actuarial probability of rebleeding from esophageal varices was lower in the EVL group (P = 0.001). A total of 42 patients of the EVL group and 30 patients of the N+I group died (P = 0.013). The multivariate Cox analysis indicated that age, serum albumin, presence of encephalopathy, and treatment were the factors predictive of mortality.

CONCLUSION

Our long-term follow-up study showed that combination of N+I therapy was inferior to banding ligation in the reduction of variceal rebleeding, but with enhanced survival.

Clinical trial: percutaneous acetic acid injection vs. percutaneous ethanol injection for small hepatocellular carcinoma--a long-term follow-up study

BACKGROUND

The long-term outcome of percutaneous acetic acid injection (PAI) and percutaneous ethanol injection (PEI) for treating small hepatocellular carcinoma (HCC) remains unclear.

AIM

To compare the long-term outcome of PAI vs. PEI for treating small HCC.

METHODS

From July 1998 to July 2004, 125 patients with small HCC were enrolled. Seventy patients receiving PAI and 55 patients receiving PEI were enrolled. There were no significant differences in the clinical characteristics between the two groups. Tumour recurrence and survival rates were assessed.

RESULTS

Mean follow-up time was 43 months. The local recurrence rate and new tumour recurrence rate were similar between the PAI and PEI groups. The PAI group had significantly better survival than the PEI group (P = 0.027). Multivariate analysis revealed that PAI was the significant factor associated with overall survival [PAI vs. PEI, RR: 0.639, 95% CI: (0.419-1.975), P = 0.038]. The treatment sessions required to achieve complete tumour necrosis were significantly fewer in the PAI group than in the PEI group (2.4 +/- 1.0 vs. 2.9 +/- 1.3, P = 0.018).

CONCLUSION

Percutaneous acetic acid injection required fewer treatment sessions than PEI and provided better survival after long-term follow-up.

Deep neck abscess: an analysis of microbial etiology and the effectiveness of antibiotics

The objective was to demonstrate the aerobic and anaerobic microbiology of deep neck space abscess and to analyze the coverage rate of different empiric antimicrobial agents. A retrospective review of hospitalized patients with deep neck abscess diagnosed at a tertiary-care, general hospital between April 2001 and October 2006. The study enrolled 100 patients. The bacterial cultures of 89 patients yielded positive results (89%). The predominant aerobes were viridans streptococci, Klebsiella pneumoniae, and Staphylococcus aureus. The predominant anaerobes included species of Prevotella, Peptostreptococcus, and Bacteroides. Five different combinations of empiric antibiotics, namely regimen 1: penicillin G and clindamycin and gentamicin, regimen 2: ceftriaxone and clindamycin, regimen 3: ceftriaxone and metronidazole, regimen 4: cefuroxime and clindamycin, and regimen 5: penicillin and metronidazole, were compared using the antimicrobial susceptibility of 89 cases. The coverage rates of regimens 1, 2, 3, 4, and 5 were 67.4%, 76.4%, 70.8%, 61.8%, and 16.9%, respectively. The coverage of regimen 5 was considerably worse than that of the other four regimens (p < 0.001). Regimen 2 was significantly better than regimen 4 (p < 0.001). Regimen 2 had better coverage than regimens 1 (p = 0.096) and 3 (p = 0.302), but the difference was not statistically significant. This study demonstrates the bacteriology of deep neck abscess and analyzes the coverage rate of different empiric antimicrobial agents. Regimens 1, 2, and 3 could be good candidates for empiric antibiotics. Pathogen-directed antimicrobial therapy should be adjusted after the culture results are obtained.

Polymorphisms of death pathway genes FAS and FASL and risk of premalignant gastric lesions

BACKGROUND

Tumorigenesis is a multistep process that begins with the abrogation of normal controls of apoptosis and cell proliferation, and the FAS receptor-ligand system is a key regulator of apoptosis. The aim of this study was to investigate whether functional polymorphisms of death pathway genes (FAS and FASL) are associated with the development of gastric atrophy and intestinal metaplasia.

PATIENTS AND METHODS

Genotypes in the promoter regions of the FAS (-1377G/A and -670A/G) and FASL (-844T/C) genes of 101 healthy individuals and 86 gastric cancer patients were determined by PCR-RFLP. Additionally, gastric histological changes were examined according to the updated Sydney System.

RESULTS

The carriage of FASL -844C allele significantly increased the risk of atrophy in the gastric corpus, with an adjusted odds ratio (OR) of 5.0 [95% confidence interval (CI), 1.5-6.8]. There were no gene-gene interactions among FASL -844T/C, FAS -1377G/A and FAS -670A/G polymorphisms in developing premalignant gastric lesions. In the 109 individuals with Helicobacterpylori infection, carrying the FAS -1377A allele was a protective factor for developing intestinal metaplasia in the antrum (OR, 0.3; 95% CI, 0.1-0.9), while carrying the FASL -844C allele was a risk factor for developing gastric atrophy in the corpus (OR, 9.4; 95% CI, 1.7-53.4).

CONCLUSION

FAS and FASL genotypes of the hosts are important determinants in the pathogenesis of gastric atrophy and intestinal metaplasia in H. pylori-infected individuals.

High-dose versus low-dose esomeprazole-based triple therapy for Helicobacter pylori infection

BACKGROUND

This prospective, randomized, controlled study was conducted to compare the efficacies of high-dose and low-dose esomeprazole-based triple therapies for Helicobacter pylori eradication in Taiwan.

MATERIALS AND METHODS

From January 2004 to June 2006, 240 H. pylori-infected patients were randomly assigned to undergo high-dose (40 mg b.d.) or low-dose (40 mg o.d.) esomeprazole combined with clarithromycin (500 mg b.d.) and amoxicillin (1 g b.d.) for one week. Follow-up endoscopy was performed at eight weeks after the end of treatment to evaluate the response to therapy.

RESULTS

Intention-to-treat analysis demonstrated no differences between eradication rates of high-dose and low-dose groups (92% vs. 90%, respectively, P > 0.05). Per-protocol analysis yielded comparable results (95% vs. 93%). Both groups exhibited similar frequencies of adverse events (13% vs. 11%) and drug compliance (96% vs. 93%). Multivariate analysis indicated that only good compliance (odds ratio: 10.3, 95% CI, 3.0-35.7) was an independent predictor of treatment success.

CONCLUSIONS

This work demonstrates that low-dose esomeprazole-based triple therapy yields a similar eradication rate as high-dose esomeprazole-based therapy in Taiwan. Since the cost of the low-dose regime is lower than that of the high-dose regime, low-dose esomeprazole-based triple therapy can reasonably be recommended for the first-line eradication of H. pylori for Taiwanese and probably most Asians.

Acute pancreatitis-associated acute gastrointestinal mucosal lesions: incidence, characteristics, and clinical significance

GOALS AND BACKGROUND

Dyspeptic symptoms are associated with acute pancreatitis, but some of them may be related to acute gastrointestinal mucosal lesions (AGML) and need acid-suppressive therapy. The aim of this prospective study was to investigate the incidence, characteristics, and clinical significance of acute pancreatitis-associated AGML.

STUDY

From January to December 2005, a total of 197 patients with acute pancreatitis were included. All patients underwent computed tomography to evaluate the severity of acute pancreatitis. They also underwent upper gastrointestinal endoscopy to detect any AGML in upper gastrointestinal tract. The clinical and laboratory data from patients with or without AGML were compared.

RESULTS

Of the 197 patients, 128 patients (65%) were found having AGML by endoscopy. The locations of AGML included esophagus (9), stomach (50), duodenum (33), combined esophagus and stomach (10), and combined stomach and duodenum (26). The incidence of AGML was more frequent in patients with male gender (P<0.01). There was no statistical significance in relationship between AGML presence and age, etiologies of pancreatitis, severity of pancreatitis according to computed tomography grading or Ranson's score, serum total bilirubin level, duration of stay, or mortality. There was also no statistical significance in relationship between AGML location and etiologies of pancreatitis.

CONCLUSIONS

Sixty-five percent of patients with acute pancreatitis complicate with AGML and may benefit by acid-suppressive therapy. The occurrence of AGML is significantly increased in male patients and is not an early predictor of severity in acute pancreatitis.

Migrating fish bone complicating a deep neck abscess

Deep neck infections are not uncommon; however, a migrating fish bone is seldom a cause of a deep neck abscess. Fish bones are a sharp foreign body and can penetrate the oropharynx or esophagus. However, this rarely occurs. We report a case of deep neck abscess resulting from the intracorporeal migration of a fish bone. Initial radiography and esophagoscopy of the neck were both negative; migration of the bone was ultimately documented by computed tomography. Surgical exploration was performed via a lateral neck incision, and the fish bone was successfully retrieved. Although fish bones are a rare etiology of deep neck abscesses, should be kept in mind when a patient has the history of fish bone ingestion.

Single daily amikacin versus cefotaxime in the short-course treatment of spontaneous bacterial peritonitis in cirrhotics

AIM: To compare the efficacy and safety of single daily amikacin vs. cefotaxime in the 5-d treatment of spontaneous bacterial peritonitis (SBP).

METHODS: Thirty-seven cirrhotic patients with SBP, 19 in group A and 18 in group B, were studied. Group A received 1 g of cefotaxime every 6 h, and group B received 500 mg of amikacin qd. Both antibiotics were administered up to 5 d and the responses were compared.

RESULTS: Infection was cured in 15 of 19 patients (78.9%) treated with cefotaxime and in 11 of 18 (61.1%) treated with amikacin. Four patients of the Cefotaxime group (21.1%) and five patients of the Amikacin group (27.8%) died. Two in each group (10.5% vs 11.1%) had renal impairment during study period. One in each group (5.3% vs 5.6%) may be considered to suffer from nephrotoxicity due to increased urinary β2-microglobulin concentration.

CONCLUSION: In this study, single daily doses of amikacin in the treatment of SBP in cirrhotics were not associated with an increased incidence of renal impairment or nephrotoxicity. However, a 5-d regimen of amikacin is less effective than a 5-d regimen of cefotaxime in the SBP treatment.

Assessment of the ability of Malassezia pachydermatis to stimulate proliferation of canine keratinocytes in vitro

OBJECTIVE

To investigate the direct interaction between canine keratinocytes and live Malassezia pachydermatis and thereby determine the role of these organisms in the pathogenesis of epidermal hyperplasia associated with Malassezia dermatitis in dogs.

SAMPLE POPULATION

Primary canine keratinocyte cultures established from skin samples obtained from clinically normal dogs.

PROCEDURE

The proliferative response of keratinocytes co-cultured with Malassezia organisms for 1, 2, or 3 days was assessed by use of direct manual counting (to determine the number of keratinocytes in both the monolayer and the medium) and immunohistochemical staining techniques involving antibodies against proliferating cell nuclear antigen (PCNA) and another cellular proliferation marker, Ki-67. The potential cytotoxic effect of Malassezia organisms was investigated by use of an apoptosis detection kit to label keratinocytes co-cultured with M. pachydermatis that underwent apoptosis.

RESULTS

No stimulatory effect of Malassezia organisms on canine keratinocyte proliferation was detected via cell counting and immunohistochemical techniques. However, there was a significant increase in dead keratinocytes in the medium with increasing numbers of Malassezia organisms in the co-culture. More apoptotic cells were observed in keratinocyte monolayers co-cultured with high numbers of M. pachydermatis than there were in monolayers cultured without Malassezia organisms, and the number increased after prolonged incubation.

CONCLUSIONS AND CLINICAL RELEVANCE

M. pachydermatis did not stimulate canine keratinocyte proliferation in vitro. The results suggested that the epidermal hyperplasia observed in dogs with Malassezia dermatitis is unlikely to be caused by a direct effect of the organism on the keratinocyte cell cycle, but is likely to involve other mechanisms.

Power microdebrider-assisted modification of endoscopic inferior turbinoplasty: a preliminary report

BACKGROUND

In this article, microdebrider-assisted modification of endoscopic inferior turbinoplasty is described. It has the advantage of superior visualization during elevation of the mucosal flap and allows precise tailoring of the resection to the needs of patients.

METHODS

From November 2001 to December 2002, 29 patients with chronic hypertrophic rhinitis treated with power endoscopic inferior turbinoplasty were available for follow-up examinations. Questionnaires and rhinomanometric studies were performed for subjective and objective evaluations. These patients were followed up for an average of 15.3 months after the operation.

RESULTS

The overall improvement in nasal obstruction was 91% in our study. Twenty-two patients received rhinomanometric studies 1 week preoperatively and 2 months postoperatively. The average nasal airflow was increased by 187 ml/min. In addition, complete relief of headaches was achieved. But the remission rates of persistent rhinorrhea and post-nasal dripping were less significant, at about 58% and 54%, respectively. Atrophic change and permanent synechiae had not yet been observed.

CONCLUSIONS

Power endoscopic turbintoplasty is a safe, simple, and effective method for the treatment of chronic hypertrophic rhinitis. It is especially handy in adjunct to endoscopic septoplasty or sinosurgery, and appears to provide a surgical choice of a minimally invasive technique. However, further study with a prospective design is needed to strengthen the evidence.

Risk factors for spontaneous bacterial empyema in cirrhotic patients with hydrothorax

BACKGROUND

Spontaneous bacterial empyema (SBEM) is a rare complication of portal hypertension. The characteristics and risk factors for SBEM are not well known. This study was performed to investigate the risk factors for SBEM in cirrhotic patients with hydrothorax.

METHODS

From July 1996 to December 1998, 862 cirrhotic patients were studied. All patients underwent chest radiography, abdominal sonography or computed tomography after admission to detect the existence of pleural effusion. Pleural fluid was obtained after thoracentesis and sent for analysis. The clinical and laboratory data from patients with sterile hydrothorax and from SBEM at the time of first episode were compared.

RESULTS

Seventeen patients had 26 episodes of SBEM during the study period, 56% (14 of 26) of these SBEM episodes were associated with spontaneous bacterial peritonitis (SBP) and 31% (8 of 26) were associated with bacteremia. The incidence of SBEM was 2% (17 of 862) in cirrhotic patients and 13% (17 of 132) in cirrhotics with hydrothorax. Patients with SBEM had a higher Child-Pugh score, lower serum albumin, prolonged prothrombin time, lower pleural fluid protein, and higher rate of associated SBP than patients with sterile hydrothorax. Multivariate analysis revealed that pleural fluid protein level (p = 0.0035) and presence of SBP (p = 0.0062) were predictive factors of SBEM. The hospitalization mortality rate of SBEM was 38%.

CONCLUSIONS

Patients with advanced liver disease, low pleural fluid protein level, or SBP are predisposed to SBEM. A diagnostic thoracentesis should be performed in cirrhotic patients with pleural effusion when infection is suspected or clinical deterioration occurs.

Transformation of triploid bermudagrass (Cynodon dactylon x C. transvaalensis cv. TifEagle) by means of biolistic bombardment

A transformation system for triploid bermudagrass ( Cynodon dactylon x C. transvaalensis cv. TifEagle) was established with a biolistic bombardment delivery system. Embryogenic callus was induced from stolons and maintained on Murashige and Skoog's medium supplemented with 30 microM dicamba, 20 microM benzylaminopurine, and 100 mg/l myo-inositol. Using the hygromycin phosphotransferase ( hpt) gene as the selectable marker gene, we obtained 75 transgenic lines from 18 petri dishes bombarded. Integration of the hpt gene into genomic DNA and transcription of hpt was confirmed by Southern and Northern blot analyses, respectively. Through suspension culture screening, we obtained homogeneously transformed plants showing stable transcription of the hpt gene.

Failure of extracts from Malassezia pachydermatis to stimulate canine keratinocyte proliferation in vitro

Epidermal hyperplasia is one of the major histopathological features seen in dogs with Malassezia dermatitis. The aim of this study was to investigate the effects of extracts and culture supernatants from Malassezia pachydermatis on the proliferation of canine keratinocytes. Keratinocyte cultures were established from normal dog skin, and cell monolayers were co-cultured with Malassezia extracts (prepared either with or without protease inhibitors) and supernatants derived from organisms grown in liquid culture. The proliferation of keratinocytes was measured using a colourimetric assay. Neither the culture supernatants nor the Malassezia extracts had significant effects on the proliferation rate of canine keratinocytes, regardless of whether protease inhibitors were present or not. The results indicate that the epidermal hyperplasia seen in Malassezia dermatitis is unlikely to be caused directly by secretion of products from the organism.

Prophylactic antibiotics in cirrhotics with upper gastrointestinal hemorrhage: a prospective, controlled trial

BACKGROUND

Infections are a frequent complication in cirrhotics, and gastrointestinal bleeding may increase the infection rate. Nonabsorbable antibiotics or quinolone have been employed to decrease the incidence of infection. Since most of these studies were performed in western countries, it is still unclear whether this holds true in our Taiwan cirrhotic patients. Thus we conducted this study using a different formula of antibiotics to evaluate the efficacy of reducing infection rates in cirrhotics with upper gastrointestinal bleeding.

METHODS

From July 1999 to August 2000, all cirrhotic in-patients presenting with upper gastrointestinal bleeding but without infection were enrolled. The patients should not have received antibiotics within 2 weeks before admission and should have expected life expectance more than 7 days. Eligible patients who had received endoscopy within 12 hours of hospitalization were randomly allocated into 2 groups. Group A received intravenous cefazolin 1 gm every 8 hours started before endoscopy. After 3 days of prophylactic parenteral antibiotics, antibiotics were shifted to oral cephalexin of 500 mg every 6 hours for 4 days. Group B served as control subjects. All patients received chest X-ray, blood and urine cultures, and ascites culture and sputum culture if ascites and sputum were found. Patients were excluded when initial blood, urine or ascites culture was positive for bacterial growth.

RESULTS

Ninety-seven patients were included. Group A was comprised of 47 patients and Group B comprised of 50 patients. There was no significant difference in age, sex, Child-Pugh's score or initial hemoglobin between the 2 groups. Proved infection developed in 6 patients of Group B. By contrast, no proved infection was found in Group A. Three organisms belonged to gram-negative bacilli and 3 organisms were gram-positive cocci. The incidence of proved infection during hospitalization was 0% in Group A and 12.0% in Group B (p = 0.027). If possible infection cases (patient's body temperature more than 38 degrees C for more than 2 days) were included, the infection rate was 6.4% in Group A and 26% in Group B (p = 0.013). Infection-related mortality occurred in 2 patients in Group B, but none in Group A.

CONCLUSIONS

Our prophylactic antibiotic treatment proved safe and effective in reducing the infection rate in cirrhotics with upper gastrointestinal bleeding.

Identification of major allergens of Malassezia pachydermatis in dogs with atopic dermatitis and Malassezia overgrowth

We have previously shown that both atopic and normal dogs generate an IgG response to antigens of Malassezia pachydermatis. The aim of this study was to compare IgE responses to separated proteins of M. pachydermatis in 28 atopic dogs with Malassezia dermatitis and 22 clinically normal dogs using Western immunoblotting. Six different detection systems were evaluated in order to assess sensitivity and eliminate nonspecific binding and cross-reactivity. The protocol yielding the best results utilized a monoclonal mouse antidog IgE, an alkaline phosphatase conjugated goat antimouse IgG which had been passed through a canine IgG column 3 times, a chemiluminescent substrate and a digital imaging system. Proteins of 45, 52, 56 and 63 kDa were recognized by more than 50% of the atopic dog sera and thus represented major allergens. Only a minority of normal dogs showed faint IgE binding to these proteins. The results indicate that the majority of atopic dogs with Malassezia dermatitis have a greater IgE response than normal dogs, suggesting an IgE-mediated immune response may be clinically important in the pathogenesis of the disease.

Inhibition of caspase-3-like activity reduces glutamate induced cell death in adult rat retina

Retinal cell death induced by over-stimulation of glutamate receptors is related to the programmed cell death or apoptosis. However, little is known about the intracellular events that lead to this cell death process in the retina. In this study, we asked if caspase-3 family cysteine proteases regulate cell death in an explant culture of adult rat retina after exposure to excessive glutamate. Cells with DNA fragmentation were first detected in the ganglion cell layer 3 h after a brief exposure to 20 mM glutamate; whilst those in the inner nuclear layer were first observed 6 h after the glutamate lesion. Caspase-3-like activity, as indicated by immunostaining of the fractin antibody that recognizes actin fragments generated by caspase-3 family proteases, was seen 40 min after glutamate treatment. Staining was first detected in the ganglion cell layer and then in the inner nuclear layer, preceding the appearance of cells with DNA fragmentation in these layers. Colocalization study showed that all cells with DNA breaks were fractin positive, indicating that caspase-3 family activity was involved in the glutamate-induced cell death in the adult rat retina. Furthermore, DEVD-CHO, a tetrapeptide inhibitor for caspase-3 family members, reduced dramatically the fractin staining and significantly alleviated glutamate-induced cell death and DNA fragmentation in the ganglion cell layer and inner nuclear layer. Inhibitor for caspase-1-like activity, YVAD-CHO, neither reduced the fractin staining nor showed comparable neuroprotective effects to the retina. We conclude that glutamate-induced apoptotic cell death in adult rat retina is mediated by a specific activation of cysteine proteases related to the caspase-3 family, and an intervention to the caspase-3 proteases provides effective protection to retinal neurons against glutamate excitotoxicity.

The effects of endoscopic variceal ligation and propranolol on portal hypertensive gastropathy: a prospective, controlled trial

BACKGROUND

Endoscopic treatment of esophageal varices may accentuate portal hypertensive gastropathy. The impact of the combination of band ligation and propranolol on this condition remains unknown.

METHODS

Patients with history of variceal bleeding were randomized to receive band ligation alone (control group, 40 patients) or a combination of band ligation and propranolol (propranolol group, 37 patients). Serial endoscopic evaluation of gastropathy was performed. Gastropathy was classified into 3 grades and scored as 0, 1, or 2.

RESULTS

Before endoscopic treatment, 17% of the control group and 22% of the propranolol group had gastropathy (p = 0.78). The occurrence of gastropathy after endoscopic treatment was significantly higher in the control group than in the propranolol group (p = 0.002). Serial endoscopic follow-up revealed that the mean gastropathy score was significantly higher in the control group than in the propranolol group (p < 0.05). In patients with gastropathy the gastropathy score reached a peak at 6 months after endoscopic treatment in both the control and propranolol groups (85% vs. 48%, respectively). After variceal obliteration, accentuation of gastropathy was significant in the control group (p < 0.01) but not in the propranolol group. Gastropathy was less likely to develop in patients who developed gastric varices. Esophageal variceal recurrence was not related to the development of gastropathy after variceal obliteration with banding. Only one patient in the control group bled from gastropathy.

CONCLUSION

Band ligation of esophageal varices may accentuate gastropathy, which in this study was partly relieved by propranolol.

Expression of engineered antibodies in plants: a possible tool for spiroplasma and phytoplasma disease control

ABSTRACT In an attempt to develop maize plants with resistance to corn stunt spi-roplasma (CSS), a single-chain Fv fragment (scFv) gene that was constructed from antibodies with strong inhibitory activity against CSS, was expressed in a cell line of maize. However, plants regenerated from this transgenic cell line showed no distinct resistance to CSS infection under the greenhouse conditions. The affinity and functionality of scFv in vivo and the locations of CSS and expressed scFv in maize could be a part of the contributing factors affecting this result. Progress of expressing antibodies in plants for plant pathogen resistance is also discussed.

Variation of the CGG repeat in FMR-1 gene in normal and fragile X Chinese subjects

The fragile X syndrome is believed to be caused by an expansion of a CGG trinucleotide repeat segment in the FMR-1 gene on the fragile X site of the long arm of the X-chromosome. To understand the variation of the CGG repeat in the FMR-1 gene in southern Chinese from the Hong Kong and Guangzhou area, we undertook the present study. A total of 83 normal and three fragile X subjects were examined. In the normal group, 16 distinct alleles, ranging in size from 272 bp to 332 bp with 17 to 37 CGG repeats were detected. A repeat size of 29 was the most frequent. Compared with data collected in the USA, the repeat size observed in this population was somewhat smaller. Whether this discrepancy is due to ethnic difference remains to be determined. The three fragile X patients examined in this study did not have a greatly expanded CGG segment. One of them may be a mosaic with one full and one premutation allele. The other two patients, although having clinical and cytological features of fragile X syndrome, had a CGG repeat size within normal range. To explain this, we infer that the mutation in these patients may be caused by other mechanisms, such as other types of FMR-1 mutation or mutation in another site. It is possible that the expansion of the CGG repeats may not be as frequent a cause of fragile X syndrome in southern Chinese as in other ethnic groups.

A novel method for cloning DNA of plant-pathogenic mycoplasmalike organisms

A novel method was developed for cloning the DNA from a representative of plant-pathogenic mycoplasmalike organisms (MLOs). This procedure utilized random amplified polymorphic DNA (RAPD) and basic recombinant DNA techniques. It consisted of amplification of total DNA from diseased plants using one oligonucleotide primer with arbitrary sequence and separation of RAPD products in agarose gels. Unique RAPD band(s) of MLO origin was (were) then recovered from the gel and cloned into the specifically designed vector pCR II. With this method, a DNA fragment of the SA2 isolate of grapevine yellows MLO was cloned. Southern blot hybridizations revealed that most of the DNA in the unique RAPD band was derived from MLO. Results from dot-blot hybridizations used for screening showed that approximately 60% of transformants harbored MLO-specific recombinant plasmids. Our approach is relatively simple, quite efficient, and not limited by the amount of diseased material available. It does not depend on DNA sequence information for primer design and does not rely on restriction endonucleases for cloning. In addition, it can be used directly for disease diagnosis and for differentiation of closely related MLOs. Our system may serve as a model for cloning DNAs of other fastidious plant pathogens.

Transcriptional activation of the c-myc oncogene in the T-47D mammary cancer cells by conditioned media from embryonic mouse fibroblasts (BALB/c-3T3). Effect of the antiestrogen ICI 164,384

The effects of the conditioned medium (CM) of embryonic mouse fibroblast (BALB/c-3T3) cells (clone A31) on the mRNA of the c-myc oncogene of the hormone-dependent T-47D mammary cancer cells were explored. After 6h incubation a significant stimulation of c-myc expression was observed with a 10% v/v concentration of CM, and the effect was even higher using a CM concentration of 30% v/v. It is suggested that this action of CM could be related to the stimulatory effect on proliferation and DNA synthesis induced by the CM, as was recently demonstrated for the T-47D cells. It was also observed that the antiestrogen ICI 164,384 (5 x 10(-6) M) can inhibit the stimulatory action of CM on c-myc expression. It is concluded that the fibroblast mouse embryonic cells contain and secrete factor(s) involved in the mechanism of proliferation of human hormone-dependent mammary cancer cells.

Identification and grouping of mycoplasmalike organisms associated with grapevine yellows and clover phyllody diseases based on immunological and molecular analyses

Immunofluorescent staining, dot blot hybridization, PCR, random amplified polymorphic DNA (RAPD) markers, and restriction fragment length polymorphism wee used to study the genetic relatedness among mycoplasmalike organisms (MLOs) associated with several geographically diverse grapevine yellows diseases (CA1, CH1, SA1, and SA2 from Bologna, Italy; GYU from Udine, Italy; GYR from Rome, Italy; and GYG from Germany). The relationship between these and MLOs associated with clover phyllody diseases in Italy (CPhB and CPhC) and Canada (CPhCa) was also examined. Two monoclonal antibodies reacted with MLOs of GYU-, CPhB-, and CPhC-infected periwinkles. Dot blot hybridization with two cloned GYU DNA fragments, GYD-1 and GYD-2 inserts, showed that both hybridized with DNAs of GYU-, CPhB-, and CPhC-infected periwinkles but not with those of GYR and CPhCa. In addition, GYD-1 insert hybridized with DNAs of CA1, CH1, SA1, SA2, and GYG. Three primer pairs were developed in PCR experiments for this study. By using primer set GYD2P1F and GYD2P1R, a 600-bp DNA fragment was amplified only when DNAs from GYU-, CPhB-, and CPhC-infected plants were used as templates. With the primer pair GYD2P1F and GYD2P2R, a 550-bp DNA fragment was amplified from GYU, CPhB, CPhC, and GYG. The primer pair GYD1P1F and GYD1P2R, on the other hand, could amplify all isolates, although the patterns of PCR products were not identical for all isolates.(ABSTRACT TRUNCATED AT 250 WORDS)