Molecular cloning of the leuB gene from Bacteroides fragilis by functional complementation in Escherichia coli

Clones containing the Bacteroides fragilis leuB-complementing gene were isolated by screening of a B. fragilis genomic library constructed in Escherichia coli. One recombinant clone, designated pOT865, with the smallest DNA insert (4.5 kb) could complement three independent leuB mutations in E. coli and the leuB-complementing determinant in pOT865 was localized to a region of 1.5-kb DNA. The results of Southern blot analysis suggested that a single copy of the cloned gene was present in the B. fragilis genome. The cloned fragment appeared to contain a sequence that could function as promoter in E. coli and direct the synthesis of a 42-kDa protein. These results suggest that the cloned segment contains the structural gene for beta-isopropylmalate dehydrogenase (leuB).

Processing and secretion of Alzheimer's disease amyloid precursor protein

We studied in vivo expression and in vitro secretion of the Alzheimer's disease amyloid precursor protein (APP). The results indicate that secretion of APP is mediated by PKC and the initial step of the processing may occur in the acidic secretory granules of the glial cells. Our results suggest that a metabolic switch of APP in neural cells is critical in amyloid deposition.

[Management of advanced renal cell carcinoma: surgical treatment of metastasis]

The prognosis of advanced renal cell carcinoma, especially with metastatic lesions was very poor. We described the outcome of surgical treatment of advanced renal cell carcinoma with metastasis. From 1964 to 1992, 279 cases of renal cancer were treated in the Department of Urology, the Center for Adult Diseases, Osaka. Sixty four cases were with distant metastasis (M1 case) and 55 cases were recurrent after radical nephrectomy (M0-M1 case). Among these 119 cases with distant metastasis, 50 cases were treated by surgical resection. Indication of surgical resection was first to obtain surgical complete regression (sCR), second to improve quality of life (QOL). Lung metastases from 14 patients (M1, 5 cases; M0-M1, 9 cases) were resected. The survival of patients with unilateral lung metastases was significantly better than that of patients with bilateral lung metastases. Bone metastases from 18 patients (7 cases to obtain sCR, 11 cases to improve QOL) were resected. The prognosis of patients with bone metastasis was very poor, and more than a 3-year survival was seen in only patients histopathologically with grade 1. QOL improvement was observed in 9 of 11 patients (82%). Solitary adrenal metastasis showed a relatively good prognosis. Surgical resection of brain metastasis was performed only to improve QOL, because all patients had other metastases. Lymph node metastasis showed in general poor prognosis. Six cases with tumor thrombus extending into inferior vena cava nephrectomized under extracorporeal circulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Complete sequence of the Bacteroides fragilis YCH46 neuraminidase-encoding gene

The nucleotide sequence of the Bacteroides fragilis neuraminidase-encoding gene (nanH) and its flanking regions was determined. The B. fragilis nanH open reading frame (ORF) of 1632 nucleotides encoded a neuroaminidase of 544 amino acid residues with a calculated molecular mass of 59.51 kDa. The amino acid sequence at the N-terminus of the deduced protein exhibited the common features of procaryotic signal sequences. The Asp box sequence, Ser-X-Asp-X-Gly-X-Thr-Trp, which is conserved among bacterial neuraminidases, was found at five positions in the deduced amino acid sequence. A single transcription start point was identified 88 nucleotides upstream of the nanH ORF. Northern blot analysis using an internal nanH probe revealed a single mRNA species with a length of 1.8 kb that could encode just the neuraminidase.

Cloning and expression of the Bacteroides fragilis YCH46 neuraminidase gene in Escherichia coli and Bacteroides uniformis

A neuraminidase-encoding gene nanH of Bacteroides fragilis strain YCH46 was cloned into the cosmid vector pHC79. The nanH gene was subcloned from the cosmid and was located within a 2.2-kb XhoI-KpnI fragment. Southern hybridization experiments demonstrated that the gene was present as a single copy on the bacterial chromosome. Neuraminidase activity expressed in the initial Escherichia coli clone was approximately 3600-fold lower than that expressed in B. fragilis YCH46. However, when nanH was transferred from E. coli to B. uniformis by mobilization of a shuttle plasmid, the transconjugant expressed 1100-fold higher activity than the E. coli donor did. These results suggest that modes of nanH expression in E. coli and Bacteroides are heterologous.

Characterization of mouse monoclonal antibody B1.4 reactive with human invasive bladder cancer and some other malignant tumors but not with normal urinary epithelium

Immunohistochemical analysis by indirect immunoperoxidase staining demonstrated that monoclonal antibody (mAb) B1.4 derived from a mouse immunized with a bladder cancer cell line EJ-1 was reactive with a high proportion of high-grade and invasive bladder tumors, but not with the majority of low-grade and superficial bladder tumors, or normal urinary epithelium. Among 71 primary bladder tumors classified by pathological grading, positive stainings were observed in 1 of 34 tumors (3%) of grade 1, 8 of 20 tumors (40%) of grade 2 and 14 of 17 tumors (82%) of grade 3. When the tumors were classified by pathological staging, positive stainings were observed in only 8 of 54 (15%) superficial tumors of stages Ta and T1, but in 15 of 17 (88%) invasive tumors of stages T2 and T3. mAb B1.4 showed restricted positive stainings with normal tissues including renal glomerulus, vascular endothelium, squamous epithelium of esophagus, glandular epithelium of prostate, and epithelium of pancreatic acinar gland and minute duct, while positive stainings were observed in a range of tumor tissues other than bladder tumor. Mixed hemadsorption assays with a panel of cell cultures showed also that the antigen recognized by mAb B1.4 was expressed on a range of tumor cell lines. These findings suggest that the antigen recognized by mAb B1.4 may appear after malignant transformation, and be an indicator of malignant potential of bladder cancer.

The efficiency of solvent extraction of mutagenic compounds in particulates exhausted from a small diesel engine

Organic materials were extracted from particulates exhausted from a small diesel engine (displacement 269 ml) by the ultrasonic extraction method with three different solvent systems, methanol, dichloromethane and a 4:1 (v:v) mixture of benzene and ethanol. These solvent-extracted materials were tested for mutagenic activity by the Ames Salmonella/microsome assay system using Salmonella typhimurium strains TA98, TA100, TA98NR and TA98/1,8-DNP6. The concentrations of 1-nitropyrene (1-NP) and 1,6-dinitropyrene (1,6-diNP) in these extracted materials were also measured after nitroreduction by high pressure liquid chromatography. The methanol-extracted and benzene-ethanol-extracted materials showed the lowest and the highest mutagenic activity, respectively. The methanol-extracted, dichloromethane-extracted and benzene-ethanol-extracted materials induced 260, 1,570 and 3,240 His+ revertants per plate per mg of extracted materials, respectively, from strain TA98 in the absence of S9 mix. These materials showed decreased mutagenicity for strains TA98NR and TA98/1,8-DNP6, indicating that the particulates in the diesel engine exhaust contained 1-NP and diNPs. Actually, the amount of 1-NP and 1,6-diNP in the methanol-extracted, dichloromethane-extracted and benzene-ethanol-extracted materials were 17.0 and 0.03 ng, 37.5 and 0.97 ng, and 71.3 and 1.03 ng per mg of extracted materials, respectively, accounting for 11.9 and 3.2%, 4.4 and 17.3%, and 4.0 and 8.9%, respectively, of the total mutagenicity of the extracted materials. From these results it is concluded that a mixture of benzene-ethanol (4:1, v/v) is the most suitable solvent for extraction of organic matter containing nitrated polycyclic aromatic hydrocarbons such as NPs from particulates in diesel engine exhaust.

Presence of mucosa-specific DNA adduct in human colon: possible implication for colorectal cancer

DNA of normal mucosa and the adjacent muscular layer from 18 adults suffering from colorectal neoplasms was examined by 32P-post-labeling analysis in order to estimate the exposure of the human colon and rectum to environmental carcinogens. Colorectal DNA samples obtained from six newborns were also examined as a normal control because they were presumed to have been minimally exposed to environmental carcinogens. One common mucosa-specific DNA adduct was found in the normal colorectal wall in all adults at the level of 0.10-34.13 adducts/10(8) nucleotides (mean +/- SD: 3.64 +/- 7.92 adducts/10(8) nucleotides), however, these were absent from the newborns' colons. Although several common spots were present in the mucosa, muscular layer and newborn tissues, there was no muscular layer-specific DNA adduct. The relationship between the levels of the mucosa-specific DNA adduct in the non-cancerous part and the histological degree of malignancy was not significant. The presence of this mucosa-specific DNA adduct in adult colon suggests that the human colon is commonly exposed mainly to one environmental carcinogen. This carcinogen is supposed to originate from foods, because the incidence of colorectal carcinoma is closely linked to dietary habits and the mucosa-specific DNA adduct was not present in newborns who had never ingested food. The incidence of adult colonic cancer originating from its mucosa is high, while cases of muscular origin or in newborn colon are rare. Therefore, the mucosa-specific DNA adduct is presumably responsible for the development of colonic cancer of epithelial origin.

[Characterization of renal cell carcinoma: current topics]

This article reviewed relatively new findings of renal cancer concerning epidemiology, molecular and cytogenic analysis for carcinogenesis, and immunological analysis. In recent years, increasing numbers of renal cancer have been found incidentally by ultrasonography or computerized tomography. These incidental tumors were detected at earlier stages and the prognosis was improved. The incidence of renal cancers detected incidentally by ultrasonic mass survey in a restricted area (incidental cancer) was 0.06%, which is much higher than the incidence of clinical renal cancers. Moreover, the incidence of renal cancers found in Japanese autopsy specimens (latent cancer) was 0.77%, which was extremely high. Moreover, the frequency of cancer multicentricity in kidneys removed for renal cancers was 0.07% by examining 100 kidneys. To investigate the biological characteristics of incidental and latent cancers including multicentric daughter tumors is a key point in determining the surgical indications. Specific oncogenes participating in the carcinogenesis of renal cancer have not been found so far, but c-myc oncogene was overexpressed in renal cancers. The deletion of 3 p chromosome was very often observed in renal cancers. The suppressor gene for carcinogens of renal cancer may be localized in 3p region. Renal cancer produced a transforming growth factor-alpha (TGF-alpha), which bound to epidermal growth factor receptor (EGFR) and upregulated the expression of EGFR and TGF-alpha. The autocrine loop of TGF-alpha and EGFR may stimulate the growth of renal cancer. Renal cancer patients had immunological reactions to autologous tumor cells in their sera, then renal tumors expressed class 1 (individually unique) antigens or class 2 (cancer shared) antigens. Immunological therapy may be useful for renal cancer. Finally, antiproliferative and antitumor effect of interferon alpha in renal cancer correlated reversely with the expression of F 33 antigen, which is expressed only in renal glomerulus and proximal tubule. We could discriminate the responder from the nonresponder for immunotherapy with interferon alpha. These findings could lead to the development of new modalities for renal cancer.

[Fluid, electrolyte, and acid-base disorders in liver cirrhosis]

The common disorders of fluid, electrolyte and acid-base metabolism observed in patients with liver cirrhosis are hyponatremia, hypokalemia, respiratory alkalosis, and metabolic acidosis, in addition to an excess accumulation of body fluids with edema and ascites formation. It has been suggested that an impaired renal sodium excretion in liver cirrhosis is caused by rather an increase in tubular sodium reabsorption than a decrease in glomerular filtration rate. In order to explain the pathophysiological mechanisms involved in initiating and maintaining sodium retention in cirrhosis, three hypotheses, namely, the "underfilling" hypothesis, the "overflow" hypothesis, and the "pepipheral arterial vasodilation" hypothesis have been proposed. However, neither of them could not fully account for the pathogenesis and pathophysiology of the avid renal sodium retention in cirrhosis. Although it is undoubted that the abnormal renal sodium handling in cirrhosis is mediated mainly by the sympathetic nervous system and the certain humoral agents such as renin-angiotensin-aldosterone system, atrial natriuretic peptide, prostaglandins, kallikein-kinin system, antidiuretic hormone and so on, the precise mechanism of the enhanced tubular sodium reapsorption induced via these factors is not well understood and still remains to be elucidated.

Adjuvant and neoadjuvant chemotherapy for invasive bladder cancer

A total of 20 patients with primary invasive bladder cancer who underwent radical cystectomy received postoperative adjuvant chemotherapy using a CAP (cyclophosphamide, doxorubicin, and cisplatin) or modified M-VAC (methotrexate, vinblastine, pirarubicin, and cisplatin) regimen. In all, 16 of the patients were treated with CAP and 4 received the modified M-VAC regimen. Of the 20 patients, 17 had transitional-cell carcinoma with or without non-transitional-cell elements. All of the patients had tumors with a histological grade of G2 (6 cases) or G3 (14 cases). As for lymph-node metastasis, there were ten N0 cases, three N1 cases, six N2 cases, and one N3 case. Adjuvant chemotherapy was usually commenced 2 weeks after the surgery and was given every 3-4 weeks for two or three cycles. The 5-year survival rate of these 20 patients was 65.9%, whereas that of 49 patients who did not receive any adjuvant chemotherapy was 30.2%. Regarding toxicity, both of the adjuvant chemotherapy regimens used in this study were generally well tolerated. The most common toxic effects were gastrointestinal symptoms, alopecia, and myelosuppression. Another 19 patients with invasive transitional-cell carcinoma of the bladder received 2 or 3 cycles of neoadjuvant chemotherapy using the modified M-VAC or MEC (methotrexate, epirubicin, and cisplatin) regimen. Of 18 pathologically evaluable patients who underwent radical cystectomy or partial cystectomy, the stage was pT0 in 3 cases (17%), pTis in 3 (17%), pT1 in 3 (17%), and pT2 or higher in 9 (50%). The 4-year survival rate of 18 patients who received neoadjuvant chemotherapy was 71.5%. Regarding toxicity, one patient died of a bowel complication after surgery, and the complication was suggested to be drug-induced.

Mutagenicity and antimutagenicity of extracts of three spices and a medicinal plant in Thailand

Three kinds of spices (caraway, coriander and black pepper seeds) and a medicinal plant called 'tong tak' in Thai (Baliospermum axillar, a species of the spurge family) were fractionated into hot water, methanol and hexane extracts. These extracts were not mutagenic for Salmonella typhimurium strains TA98 and TA100 by the Ames assay. However, when the extracts were treated with nitrite, samples of the water and methanol extracts were mutagenic for strain TA100 without metabolic activation. The mutagenicity of the nitrite-treated methanol and hot water extracts of black pepper was highest (8380 and 22,200 His+ per 0.1 g of spice powder, respectively), and that of the nitrite-treated hot water extracts of caraway and tong tak was moderate. The hot water extracts were examined for their antimutagenic activity against mutagenicity induced by various carcinogens by the Ames assay, using the preincubation technique. The tested samples (equivalent to 1-2 mg of spice powder) reduced the mutagenicity induced by 2.7 nmole (397 ng) of N-methyl-N'-nitro-N-nitrosoguanidine by more than 84%, and that induced by dimethylnitrosamine (1.48 mg) or ICR-170 (10 ng) by 30-60%. However, they did not inhibit the mutagenic activity of 1-nitropyrene, 3-nitrofluoranthene, AF-2, methyl methanesulfonate, N-ethyl-N'-nitro-N-nitrosoguanidine, 2-aminoanthracene, 2-acetylaminofluorene, benzo[a]pyrene or IQ.

[Tuberculosis of the female urethra: a case report]

A 52-year-old female with the chief complaint of miction pain was referred for the examination of a urethral nodule. Physical inspection revealed the meatus to be reddish and swollen. The painless nodule (1 x 1 x 2 cm) was situated between the urethra and vagina on transvaginal examination. Chest X-ray, drip infusion pyelography (DIP) and urethrocystography (UCG) showed no evidence of tuberculosis. Bladder mucosa was normal on cystoscopy. Mycobacterium tuberculosis was not detected from urine or sputum. The nodule was resected along with a portion of the urethra. Histopathological examination revealed tuberculous granuloma of the urethra.

Urinary 1-hydroxypyrene as a marker of exposure to polycyclic aromatic hydrocarbons in environment

The concentrations of pollutants, especially polycyclic aromatic hydrocarbons (PAHs), originating from automobile emissions are high in areas around urban arterial roads. To investigate the possibility of using urinary 1-hydroxypyrene (1-POH) a metabolite of pyrene, as a marker for estimating the amount of human exposure to PAHs, both an animal experiment and an ecological correlation study were conducted. Rats were exposed to one of two sources of PAH: diesel engine emissions containing particulate matter and NO2 at average concentrations of 4.20 mg/m3 and 2.90 ppm, respectively, or, for the control group, air having the respective average concentrations of 0.01 mg/m3 and 0.02 ppm. The concentration of pyrene was 36 ng/mg in the particulate matter in the diluted diesel engine exhaust and 9.0 ng/g in the feed to the rats. Urinary 1-POH levels in the rats of the exposure group increased remarkably over those of the control group, 2.4 times as much by the 2nd week of exposure and 5.6 times by the 4th and 8th weeks. The ecological correlation study was conducted in 1988 and 1989 in two area of Tokyo along arterial roads (Meguro and Itabashi Wards) and in one suburban area (Higashiyamato City) to measure urinary 1-POH levels in elementary school children who lived in those areas. Urinary samples were collected in October in 1988, as well as in January, May, and July in 1989. Throughout the period of investigation, the schoolchildren in the highly NOx-polluted Meguro and Itabashi Wards showed significantly higher urinary 1-POH levels than the children in the less-polluted Higashiyamato City by a factor of 1.1-1.6. These results suggest that the urinary 1-POH level could be used as a good marker for estimating the amount of exposure of residents to PAHs.

Membrane cofactor protein (MCP, CD46) in seminal plasma and on spermatozoa in normal and "sterile" subjects

A sperm protein of molecular mass 43 kDa (the spermatozoa membrane cofactor protein, smMCP) and a seminal plasma protein of 60 kDa (ssMCP) were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting with four monoclonal antibodies (mAb) against membrane cofactor protein (MCP, CD46). These proteins served as factor I cofactors for the cleavage of methylamine-treated C3 (C3ma), the activity of which was blocked by M75, an MCP cofactor-activity-blocking mAb. Thus, these semen proteins are antigenic and functional homologous of MCP. On SDS-PAGE analysis these MCP migrated as single-band proteins which differed from the two-band forms of MCP expressed on other cells. smMCP was N-glycosylated but not O-glycosylated, while ssMCP was O-glycosylated: after deglycosylation of these proteins bands were detected at 38-40 kDa and 43 kDa on SDS-PAGE, respectively. These semen MCP are therefore, structurally different from the conventional MCP. ssMCP in both normal and "sterile" subject groups was determined by sandwich enzyme-linked immunosorbent assay. Seminal plasma in the two groups contained 250-700 ng/ml ssMCP. The difference between the two groups was marginal, although samples from normal subjects tended to show higher concentrations of ssMCP than samples from "sterile" subjects. No molecular difference was observed with ssMCP and smMCP in the two groups by SDS-PAGE/immunoblotting analysis. Immunohistochemical analysis suggested that MCP was positive in glandular epithelial cells and the lumen of the prostate, and in most intra-lumen cells of the testis. Using antibody M177, solubilized prostate and testis were analyzed by immunoblotting and compared with other cell MCP. The major band of MCP in the testis, but not in the prostate, was of 60 kDa, which aligned with ssMCP. No band of testis or prostate MCP, however, aligned with smMCP. ssMCP may be produced in the testis, while the origin of smMCP remains unknown. We hypothesize that ssMCP is important in the survival of spermatozoa, protecting them against local secretion of immunoglobulin and complement in the female genital tract, and that smMCP, which is expressed on acrosome-reacted spermatozoa, plays an essential role in the interaction of spermatozoa with oocytes.

Biological activities of the intestinal microflora in mice treated with antibiotics or untreated and the effects of the microflora on absorption and metabolic activation of orally administered glutathione conjugates of K-region epoxides of 1-nitropyrene

To elucidate the effects of the intestinal microflora on absorption and activation of glutathione conjugates of 4,5-epoxy-4,5-dihydro-1-nitropyrene (1-NP 4,5-oxide) and 9,10-epoxy-9,10-dihydro-1-nitropyrene (1-NP 9,10-oxide), we investigated the biological activities of the microflora in specific-pathogen-free (SPF) mice and SPF mice treated with various antibiotics and established the methodology of antibiotic treatment to eliminate the intestinal microflora. Mice were given various kinds of antibiotics by intragastric gavage twice a day for five days. A mixture of antibiotics bacitracin (BC), neomycin (NM) and streptomycin (SM) was the most effective in reducing the various activities of the intestinal microflora. The treatment decreased the bacterial counts and the activities of enzymes of the intestinal contents cysteine conjugate beta-lyase (beta-lyase), beta-glucuronidase and nitroreductase which were derived from the intestinal microflora, but did not affect the activities of gamma-glutamyltransferase and aminopeptidase which were derived from host tissue cells. Furthermore, the treatment did not affect absorption of glucose from the intestinal tract, body weight or liver enzyme activities. The treatment with only an aminoglycoside antibiotic, kanamycin or NM, decreased neither the number of anaerobes in the intestine nor the beta-lyase or nitroreductase activities from the intestinal contents. Glutathione conjugates of [3H]-1-NP oxides were administered to two groups of ICR mice that had been treated with antibiotics (BC, NM, SM) or saline (control group) orally. The radioactivity in the blood increased and reached the maximum level 2 or 3 h after administration of the conjugates in the control group; however, that in the antibiotic-treated group was only slightly increased if at all. Excretion of [3H]-labeled metabolites into the urine was approximately 20% of the total dose in the control group, but it was < 2% in the antibiotic-treated group during 48 h. After 48 h, DNA in the lower intestinal mucosa was extracted and the DNA adducts were analyzed by the 32P-postlabeling method. Three new DNA adducts were detected in the lower intestinal mucosa of the control group but not of the antibiotic-treated group. These results suggest that the intestinal microflora plays an important role in absorption of the metabolites of glutathione conjugates of 1-NP oxides from the intestinal tract and activation of the metabolites in the intestine.

[Successful interferon therapy of renal cell carcinoma with tumor thrombus extending into the inferior vena cava--a case report]

It is a fact that there are few effective drugs available except for interferon for that treatment of renal cell carcinoma, and the efficacy rate of interferon is less than 10% even if multiple drug regimens are included. We have experienced a case of renal cell carcinoma in whom interferon therapy was successful in reducing the primary lesion and tumor thrombus extending into the inferior vena cava. A 57-year-old man was admitted to our department with a complaint of macroscopic hematuria. Computed tomography and magnetic resonance imaging revealed a right renal tumor and the tumor thrombus. Because of the past history of his myocardial infarction, a radical operation was considered risky. So we started interferon therapy. Four months after the start of interferon therapy, the primary lesion and the tumor thrombus markedly reduced in their size, and the clinical response was evaluated as partial response by response criteria for urological cancer treatment. Therefore, radical nephrectomy and tumor thrombectomy were performed with extracorporeal circulation. Histopathologically, necrosis and lymphocyte infiltration into the cancer cell focus were seen, and these immunologic reactions were considered at the affection of interferon. In some case, interferon therapy is a useful and safe in the treatment of the primary lesion of renal cell carcinoma, and further investigation must be studied.