Molecular characterization of a plasmid isolated from Riemerella anatipestifer

Sixty strains of Riemerella anatipestifer were isolated from ducks and geese with infectious serositis in Taiwan. Sixty per cent of the isolates (36/60) contained a 3.9 b plasmid, 12% (7/60) contained 6.5 b and 16 b plasmids, 5% (3/60) contained 2.9, 16 and 18 b plasmids and 13% contained no plasmid (14/60). The 3.9 b plasmid (designated as pCFC1) was completely sequenced to determine if it encoded virulence factors. pCFC1 was 27% G-C and had four large open reading frames (ORF). Two of the ORFs (designated as VapD1 and VapD2) encoded proteins that shared 80, 83, 69 and 67 (VapD1) and 50, 48, 21 and 20% (VapD2) identity with virulence-associated proteins of Actinobacillus Actinomycetemcomitans, Dichelobcater nodosus, Haemophilus influenzae and Neisseria gonorrheae, respectively. pCFC1 also had an ORF (designated as RepAl) that encoded a protein with approximately 30% identity to the RepA proteins of Neisseria gonorrhoeae, Campylobactor hyointestinalis and Pseudomonas aeroginosa. The region upstream of the RepA ORF had an A-T-rich region that was followed by four 21 bp perfect and one 20 bp imperfect direct repeat. The fourth ORF (designated as RepA2) encoded a protein with a region that was 44% homologous to the Helicobactor pylori replication protein.     

Comparison of antigen expression on normal urothelial cells in tissue section and tissue culture

Antigenic characterization of urothelial cells cultured from normal adult ureter was performed. These cells were cultured using a simplified isolation and culture technique and a commercially available serum-free medium. The cells growing in these cultures had epithelioid morphology and normal quantities of DNA. The antigen expression on these cultured normal urothelial cells was evaluated using a panel of monoclonal antibodies: 5G6.4, AN43, URO-5, anti-keratin and anti-blood group antibodies, and 425 (anti-epidermal growth factor receptor). Lower levels of anti-A and AN43 binding on cultured cells were observed than are seen on urothelial cells in sections of normal ureter, while the binding of anti-blood group H, 5G6.4, and URO-5 was unchanged. Binding of anti-epidermal growth factor receptor antibody 425 was improved if the cells were grown in medium lacking epidermal growth factor. These results confirm the urothelial origin of these cultured urothelial cells but indicate that some antigenic differences between cultured normal urothelial cells and urothelial cells in situ in the normal ureter exist.     

谷参肠安胶囊长期毒性试验

本文报告谷参肠安胶囊大鼠长期毒性试验,结果表明,谷参肠安胶囊对动物的一般状况,体重增长、外周血象、肝肾功能及病理组织学检查等未见明显毒性。     

A study of the relationship between ambient lead and blood lead among lead battery workers

 Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories. Received: 28 May 1996/Accepted: 30 August 1996     

Photoinactivation of bladder tumor cells by methylene blue: study of a variety of tumor and normal cells

Human bladder cancer cell lines, J82, Yen-87, Shen-87 and Zoa-88, and murine bladder cancer cell lines, MBT-2 and M1660, were used as target cells for dye-sensitized photoinactivation study in using methylene blue. Normal fibroblast cells, FB-1 and FB8490, were used as control group. The cytoplasmic activity of lactic dehydrogenase, soft agar clonogenic assay, and in vivo tumor growth, survival rate and tumor taking rate with or without photoinactivation were monitored and compared between different cell lines. Efficacy of photoinactivation was time-related and more than 90 per cent of cytotoxicity could be obtained within 60 minutes of illumination. The plateau of cytotoxicity curve could be achieved after staining for 30 minutes by methylene blue under the same illumination time. Normal fibroblasts had the same features with cancer cells. Photoinactivation of tumor cells showed significant inhibition of tumor growth and tumor taking rate in experimental animals. Survival rate was also significantly prolonged in the animals with tumor cells receiving photoinactivation. These results suggest that methylene blue-sensitized photoinactivation may be useful as an adjuvant photochemotherapy for superficial bladder cancer.     

Features of head injury in a developing country--Taiwan (1977-1987)

Certain features of head-injured patients admitted to the Chang Gung Memorial Hospital in Taiwan during the period 1977 to 1987 were reviewed. The most common causes of injury were motorcycle accidents (56.3%) and street accidents with pedestrian injury (29.47%). The age groups with the greatest incidence of injury were aged 16-20 years, 21-25 years, and 25-30 years. The pedestrian group involving the highest incidence of injury was less than 10 years of age. Overall mortality was 17.26%. The injured pedestrian group had the highest mortality (19.1%). Initial clinical assessment was recorded using the Glasgow Coma Scale. Head-injured patients with a GCS less than 8 had a mortality in the injured pedestrian group of 46%, whereas the mortality rate in the motorcycle accident group was 41%. Additional features studied were time of occurrence of injury and pattern of injury. Information gathered from this study would suggest the need to establish a Head Injury Prevention Program in Taiwan. This of course implies major cooperation among the providers of health care delivery, the medical profession, legislators, and the government at all levels.     

Primary cutaneous rhabdomyosarcoma

We report an unusual case of primary cutaneous embryonal rhabdomyosarcoma presenting as a solitary skin lesion on the anterior chest of a 20-month-old child. The tumor was characterized by small, round to oval, poorly differentiated cells. Immunohistochemically, the tumor was negative for NSE, S-100 protein, LCA, and keratin but positive for muscle-specific actin, myoglobin, desmin, and vimentin, thus indicating the presence of myogenous differentiation. Ultrastructural analysis demonstrated thick and thin filaments. Special studies showed no evidence of a primary rhabdomyosarcoma in the patient at a more typical location, nor was there any evidence of metastases.     

Repeat hepatic resections for colorectal metastases

We identified 106 patients who had undergone complete resection of isolated colorectal hepatic metastases. Nine of these patients subsequently underwent repeat liver resections for isolated hepatic recurrences. The median follow-up for these patients was 21 months. One postoperative death was related to the second hepatectomy. At the time of last follow-up, five patients were alive and free of recurrent disease at 9, 19, 31, 50, and 67 months after their second hepatic resection. The remaining three patients were alive, but disease had recurred 11 months after resection in the first patient, 12 months after resection in the second, and 18 months after resection in the third. Among these three patients, two had solitary pulmonary nodules, which were resected, and one had unresectable liver disease. Our experience and a review of the literature suggest that repeat hepatic resection for isolated colorectal metastases can result in long-term survival in selected patients.     

Detection of RAS mutations in archival testicular germ cell tumors by polymerase chain reaction and oligonucleotide hybridization.

Preliminary studies of RAS mutational activation in human testicular germ cell neoplasms have yielded conflicting results. Whereas two studies of clinical material revealed a significant incidence of N- and KRAS mutations, two studies of a variety of germ cell lines failed to document RAS mutations. To clarify the incidence of RAS mutations in these tumors, we studied archival paraffin-embedded, formalin-fixed orchiectomy specimens from 25 nonseminomas (NSGCT), 18 seminomas (SEM), and one Leydig cell tumor. For 14 of the 44 neoplasms, DNA was also available from nonmalignant testis adjacent to the tumor. Six age-matched patients had testes removed because of nonmalignant disease and were studied as controls. Polymerase chain reaction (PCR) amplified the K-, N-, and HRAS 12, 13, and 61 codons of these specimens, and mutations were detected with mutation-specific oligonucleotide probe hybridization of Southern and slot blots. Four mutations were found in KRAS 12 (4/44;[9.1%]). One seminoma [1/18(5.6%)] contained the mutation GGT(GLY)----CGT(ARG), and three NSGCT [3/25(12%)] were found to have GGT(GLY)----GAT(ASP) mutations. One of the NSGCT mutations was detected in adjacent nonmalignant tissue, but the corresponding tumor did not contain any detectable mutation. No mutations were detected at KRAS 13 or 61, in NRAS or HRAS 12, 13, or 61, or in the control normal testes. PCR, slot blots, and hybridizations were performed twice by two separate investigators for confirmation of results. PCR-generated mutation-specific positive controls were created for all possible RAS mutations, and these along with wild-type DNA controls were integral to interpretation of the oligonucleotide mismatch hybridization assay. By using positive and negative controls, we have detected a relatively low incidence of RAS mutations in archival human testicular germ cell tumors.