Clonal heterogeneity in human esophageal squamous cell carcinomas on DNA analysis

Cancers are thought to arise through multistep accumulation of somatic mutations in the progeny of a single cell. Multiple mutations may induce molecular intratumor heterogeneity. Therefore, we examined molecular clonal heterogeneity in esophageal squamous cell carcinomas. Twenty-four esophageal squamous cell carcinomas and associated lymph node metastases were examined for microsatellite alterations, and abnormalities of the p53 and transforming growth factor-beta type II receptor (TGF-beta RII) genes. There were eight cases (33%) showing different patterns of loss of heterozygosity in primary tumors and metastatic lymph nodes with microsatellite markers. On the other hand, the abnormalities of p53 were identical in all these cases. No mutation was detected in the simple repeated sequences of the TGF-beta RII gene. These results indicate that molecular clonal heterogeneity exists in esophageal squamous cell carcinomas. Therefore, care is necessary in preoperative genetic diagnosis using biopsy samples.

[Clinical evaluation of sulbactam/cefoperazone for lower respiratory tract infections. Correlation between the efficacy of sulbactam/cefoperazone and beta-lactamase]

The efficacy and safety of sulbactam/cefoperazone (SBT/CPZ) were evaluated in 42 patients with respiratory tract infections, including pneumonia (29 patients) and lower respiratory tract infections (5 patients). Overall clinical efficacy rates (excellent + good) were 79% in pneumonia and 80% in respiratory tract infections in 34 patients evaluated for clinical efficacy. It was excellent that the clinical efficacy rate was 92% in mild and moderate pneumonia. Pathogens isolated from sputa were 31 strains, including 8 strains of Pseudomonas aeruginosa, 7 of Streptococcus pneumoniae, 3 of Staphylococcus aureus and 3 of Haemophilus influenzae. Since the isolates were eradicated in 18 strains, replaced in 3, unchanged in 2 and unknown in 8, the overall eradication rate was 91%. The eradication rates were 89% in beta-lactamase producing strains and 100% in beta-lactamase positive sputum, and excellent or good in 19 (83%) of 23 patients with beta-lactamase negative sputum. The eradication rate was 88% in 5 patients with beta-lactamase positive sputum. One patient experienced a moderate rash. Abnormal laboratory test values were observed in 10 patients (26.3%), but these abnormalities were mild and transient. These results suggested that SBT/CPZ was effective and safe for the treatment of respiratory tract infections caused by beta-lactamase producing as well as beta-lactamase non-producing bacteria.

Increased Deoxycytidine Kinase mRNA Level After Treatment with Interleukin-3

Pretreatment of IL-3 to Kasumi-1 human acute myeloid leukemia cells enhanced 1-B-D-arabinofuranosyl cytosine (ara-C) cytotoxicity 1.2. to 1.4-fold (median 1.3). To clarify the mechanism of interleukin-3 (IL-3) on ara-C cytotoxicity, we investigated the level of deoxycytidine kinase mRNA with the competitive polymerase chain reaction method and enzyme activities, the incorporation of [(3)H] ara-C into DNA and intracellular ara-cytidine triphosphate (CTP) levels with high-performance liquid chromatography and analyzed cell cycles. The level of deoxycytidine kinase mRNA showed a fourfold increase (88.3 plus minus 4.33 amol &mgr;g of total RNA) at 3 days after treatment with IL-3 compared to control (20.3 plus minus 4.33 amol &mgr;g). After IL-3 treatment, ara-C incorporation into the DNA was increased to 1.33 to 1.83-fold (median, 1.73-fold). The G0/G1 late-phase and S-phase percentages of cells were increased from 28.99 to 78.73% in the IL-3 treatment group as compared to control. These results indicate that IL-3 pretreatment increases the level of deoxycytidine kinase mRNA and ara-C incorporation into the DNA and also increases ratios of G0/G1 late-phase and S-phase subsequent to an enhancement of ara-C cytotoxicity against leukemia cells.

Deoxycytidine kinase mRNA levels in leukemia cells with competitive polymerase chain reaction assay

Deoxycytidine kinase (dCyd kinase) is important for the phosphorylation of several different nucleoside antimetabolites. To understand the significance of dCyd kinase levels in chemotherapy, dCyd kinase mRNA levels were evaluated in several cells with a quantitative competitive polymerase chain reaction (PCR) assay. dCyd kinase catalytic activity and intracellular ara-CTP production were also compared with the levels of dCyd kinase mRNA. The assay was able to show: (i) that dCyd kinase catalytic activity and dCyd kinase mRNA levels were correlated in cells; (ii) that dCyd kinase mRNA levels were more sensitive in lower levels of 10 amol/micrograms of total RNA; and (iii) in cytosine arabinoside (ara-C)-resistant cells, both dCyd kinase mRNA levels and intracellular ara-CTP levels were lower compared with levels in sensitive cells. The PCR assay for dCyd kinase mRNA could be useful in the selection and monitoring of patients treated with nucleosides that are activated by this enzyme.

A case of prolonged human parvovirus B19 DNA-emia associated with polyclonal B cell activation

The current paper reports an 8 year old girl with arthralgia and polyclonal B cell activation induced by human parvovirus B19 infection (HPV B19). The infection was diagnosed by the presence of the virus genome in sera. The patient presented with transient arthritis in the wrist, ankle joint and neck and elevation of immunoglobulin IgM antibodies to HPV B19 and rubella, antibodies to Mycoplasma and antistreptolysin O but without the typical clinical features of erythema infectiosum. The polyclonal B cell activation was paralleled by the presence of the virus genome of HPV B19 in sera. In some children with arthralgia, it is important to examine the genomes of viruses that may cause arthritis as well as the antibody titers to the viruses.

Characteristics of Epstein-Barr virus-associated gastric carcinoma with lymphoid stroma in Japan

BACKGROUND

Gastric carcinoma with lymphoid stroma (GCLS), known to have a more favorable prognosis than ordinary gastric carcinoma, has been suggested to be closely associated with the Epstein-Barr virus (EBV). However, there are many clinicopathologic problems that remain unsolved.

METHODS

In 21 patients, 26 GCLS lesions and 4 non-GCLS intramucosal adenocarcinomas that developed synchronously or metachronously with GCLS were examined for EBV involvement by in situ hybridization (ISH) and were analyzed clinicopathologically. In addition, nine patients who had advanced gastric carcinoma with massive liver metastases, who showed good response to chemotherapy and had prolonged survival, were examined for the presence or absence of EBV-associated GCLS.

RESULTS

On ISH with EBV-encoded small RNAs, diffuse hybridization signals were noted in 22 (84.6%) of 26 GCLS. Hybridization signals were also noted in all four non-GCLS adenocarcinomas accompanying GCLS. As a result, hybridization signals were noted in nine of ten cancerous lesions in four cases of synchronous multiple cancers and in all five cancerous lesions in two cases of metachronous multiple cancers. Long term survivors with liver metastases included two patients with EBV-associated GCLS.

CONCLUSION

Approximately 84.6% of GCLS were related to EBV. EBV-associated GCLS constitutes one-half of the EBV-infected stomach cancers in our institution. The complete response and long term survival after conventional chemotherapy of two patients with Stage IV GCLS suggests that this form of gastric carcinoma may be especially sensitive to this treatment. The identification of EBV-associated synchronous multicentric cancers of both GCLS and non-GCLS type suggests that EBV infection may be an early event in the induction process of these tumors.

Characteristics of Epstein-Barr virus-associated gastric carcinoma with lymphoid stroma in Japan

BACKGROUND

Gastric carcinoma with lymphoid stroma (GCLS), known to have a more favorable prognosis than ordinary gastric carcinoma, has been suggested to be closely associated with the Epstein-Barr virus (EBV). However, there are many clinicopathologic problems that remain unsolved.

METHODS

In 21 patients, 26 GCLS lesions and 4 non-GCLS intramucosal adenocarcinomas that developed synchronously or metachronously with GCLS were examined for EBV involvement by in situ hybridization (ISH) and were analyzed clinicopathologically. In addition, nine patients who had advanced gastric carcinoma with massive liver metastases, who showed good response to chemotherapy and had prolonged survival, were examined for the presence or absence of EBV-associated GCLS.

RESULTS

On ISH with EBV-encoded small RNAs, diffuse hybridization signals were noted in 22 (84.6%) of 26 GCLS. Hybridization signals were also noted in all four non-GCLS adenocarcinomas accompanying GCLS. As a result, hybridization signals were noted in nine of ten cancerous lesions in four cases of synchronous multiple cancers and in all five cancerous lesions in two cases of metachronous multiple cancers. Long term survivors with liver metastases included two patients with EBV-associated GCLS.

CONCLUSION

Approximately 84.6% of GCLS were related to EBV. EBV-associated GCLS constitutes one-half of the EBV-infected stomach cancers in our institution. The complete response and long term survival after conventional chemotherapy of two patients with Stage IV GCLS suggests that this form of gastric carcinoma may be especially sensitive to this treatment. The identification of EBV-associated synchronous multicentric cancers of both GCLS and non-GCLS type suggests that EBV infection may be an early event in the induction process of these tumors.

Heterogeneous effects of G-CSF and GM-CSF on cell growth and ara-C cytotoxicity in childhood leukemias which express myeloid markers

It is uncertain if acute lymphoblastic leukemia (ALL) cells expressing myeloid makers can respond to granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF). We investigated the effects of G-CSF (0.01 microgram/ml) and GM-CSF (0.01 microgram/ml) on [3H]thymidine (TdR) uptake, and the cytotoxicity of 1-beta-D-arabinofuranosylcytosine (ara-C) in leukemia cells from 17 pediatric patients. ALL cells without myeloid markers did not respond to G-CSF or GM-CSF. On the other hand, these cytokines enhanced the [3H]TdR uptake and cell growth, not only of AML cells but also of ALL cells expressing myeloid antigens. However, G-CSF and GM-CSF did not always enhance the growth inhibitory effect of the cell cycle specific drug ara-C when the cells were co-cultured with the drug. There was no relationship between cell growth and the amount of [3H]TdR incorporation or the intracellular ara-CTP level. These results indicate the heterogeneous effects of G-CSF and GM-CSF on cell growth and ara-C sensitivity in childhood leukemia cells.

On the EEG component waves of multi-infarct dementia seniles

Component waves of EEGs led from the F3-A1, C3-A1, O1-A1, and O2-A2 scalp regions of 24 multi-infarct dementia seniles (MID) patients (ages 58 to 85 years, average 73.3 years) and eight to 19 normal, healthy, adult (NA) subjects were obtained by autoregressive component analysis. Some differences in the component waves were demonstrated between the two groups of subjects. (1) The characteristics of the EEG component waves, including the natural, damping, and resonance frequencies, their power, regularity, etc. were determined, and compared between MID patients and NA subjects. (2) No significant difference was found between male and female patients in the occurrence rate of 11 types of component waves. (3) On the average, the alpha wave frequency was lower in MID patients. (4). Slow alpha waves (7.5 to 9.4 Hz) of MID patients were superior to those of NA subjects, whereas typical alpha waves (9.5 to 11.4 Hz) were inferior to those of NA subjects. (5) The power of alpha waves in the F3-A1 and C3-A1 regions of MID patients was superior to that of NA subjects, whereas the result was reversed in the O1-A1 and O2-A2 regions. However, there was less regularity of alpha waves in all regions among MID patients. (6) The theta wave frequency in all regions was higher in MID patients than in NA subjects. (7) Both the power and regularity of theta waves of MID patients were superior to those of NA subjects in all regions. (8) The average number of delta waves that appeared in the O1-A1 and O2-A2 regions was larger in MID patients than in NA subjects. EEG were led from the F3-A1, C3-A1, O1-A1, and O2-A2 scalp regions of multi-infarct dementia seniles (MID) patients, who had sleep disorders, such as reversed day-time sleep patterns or irregular sleep-wake patterns, frequently accompanied by behavior disorders, such as wandering, violent behavior, and/or delirium. Examination by the method of EEG pattern discrimination revealed some differences in EEG component waves in comparison with normal, healthy, adult (NA) subjects.

K-ras point mutations in cancerous and noncancerous biliary epithelium in patients with pancreaticobiliary maljunction

BACKGROUND

Pancreaticobiliary maljunction (PBM), an anomalous union of the pancreatic duct with the common bile duct, has frequently been shown to be associated with biliary carcinoma. However, the mechanism of carcinogenesis is unknown.

METHODS

Mutations of the K-ras oncogene were examined in cancerous and noncancerous biliary tract epithelium of 20 patients with PBM by an extraction of DNA from surgically resected histologic specimens. DNA was analyzed by a polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) method and direct sequencing.

RESULTS

An abnormally mobilized DNA band was detected not only in cancerous epithelium but also in hyperplastic, metaplastic, and inflammatory epithelium of the gallbladder and/or common bile duct in patients with PBM. Among the biliary epithelium of patients with PBM, point mutation of K-ras oncogenes were detected in 4 of 5 (80%) cancerous epithelium, 7 of 12 (58%) hyperplastic and metaplastic epithelium, and 8 of 18 (44%) inflammatory epithelium, whereas no point mutation of the K-ras oncogene was detected in the gallbladder epithelium in 3 control patients without PBM. Direct sequence analysis of the K-ras oncogene revealed the mutation at codon 12 substituting the wild-type glycine (GGT) for aspartic acid (GAT) in all cancerous lesions of patients with PBM. Simultaneous two-point mutations from the wild-type glycine (GGC) to arginine (CGC) at codon 13 associated with the mutation at codon 12 were also found in one case of gallbladder carcinoma and one case of bile duct carcinoma.

CONCLUSIONS

K-ras gene mutation is involved in the carcinogenesis of biliary tract epithelium in patients with PBM, and appears to be a high risk factor for carcinogenesis of the biliary tract.

Oxygen equilibrium properties of chromium (III)-iron (II) hybrid hemoglobins

Cr(III)-Fe(II) hybrid hemoglobins, alpha 2(Cr) beta 2(Fe) and alpha 2(Fe) beta 2(Cr), in which hemes in either the alpha- or beta-subunits were substituted with chromium(III) protoporphyrin IX (Cr(III)(PPIX), were prepared and characterized by oxygen equilibrium measurements. Because Cr(III)PPIX binds neither oxygen molecules nor carbon monoxide, the oxygen equilibrium properties of Fe(II) subunits within these hybrids can be analyzed by a two-step oxygen equilibrium scheme. The oxygen equilibrium constants for both hybrids at the second oxygenation step agree with those for human adult hemoglobin at the last oxygenation step (at pH 6.5-8.4 with an without inositol hexaphosphate at 25 degrees C). The similarity between the effects of the Cr(III)PPIX and each subunits' oxygeme on the oxygen equilibrium properties of the counterpart Fe(II) subunits within hemoglobin indicate the utility of Cr(III)PPIX as a model for a permanently oxygenated heme within the hemoglobin molecule. We found that Cr(III)-Fe(II) hybrid hemoglobins have several advantages over cyanomet valency hybrid hemoglobins, which have been frequently used as a model system for partially oxygenated hemoglobins. In contrast to cyanomet heme, Cr(III)PPIX within hemoglobin is not subject to reduction with dithionite or enzymatic reduction systems. Therefore, we could obtain more accurate and reasonable oxygen equilibrium curves of Cr(III)-Fe(II) hybrids in the presence of an enzymatic reduction system, and we could obtain single crystals of deoxy-alpha 2(Cr) beta 2(Fe) when grown in low salt solution in the presence of polyethylene glycol 1000 and 50 mM dithionite.

Characteristics of Epstein-Barr virus-associated gastric carcinoma with lymphoid stroma in Japan

BACKGROUND

Gastric carcinoma with lymphoid stroma (GCLS), known to have a more favorable prognosis than ordinary gastric carcinoma, has been suggested to be closely associated with the Epstein-Barr virus (EBV). However, there are many clinicopathologic problems that remain unsolved.

METHODS

In 21 patients, 26 GCLS lesions and 4 non-GCLS intramucosal adenocarcinomas that developed synchronously or metachronously with GCLS were examined for EBV involvement by in situ hybridization (ISH) and were analyzed clinicopathologically. In addition, nine patients who had advanced gastric carcinoma with massive liver metastases, who showed good response to chemotherapy and had prolonged survival, were examined for the presence or absence of EBV-associated GCLS.

RESULTS

On ISH with EBV-encoded small RNAs, diffuse hybridization signals were noted in 22 (84.6%) of 26 GCLS. Hybridization signals were also noted in all four non-GCLS adenocarcinomas accompanying GCLS. As a result, hybridization signals were noted in nine of ten cancerous lesions in four cases of synchronous multiple cancers and in all five cancerous lesions in two cases of metachronous multiple cancers. Long term survivors with liver metastases included two patients with EBV-associated GCLS.

CONCLUSION

Approximately 84.6% of GCLS were related to EBV. EBV-associated GCLS constitutes one-half of the EBV-infected stomach cancers in our institution. The complete response and long term survival after conventional chemotherapy of two patients with Stage IV GCLS suggests that this form of gastric carcinoma may be especially sensitive to this treatment. The identification of EBV-associated synchronous multicentric cancers of both GCLS and non-GCLS type suggests that EBV infection may be an early event in the induction process of these tumors.

Effects of thyroid hormone on carbonic anhydrase I concentration in human erythroid burst-forming unit-derived cells

Individuals with hyperthyroidism exhibit red blood cell concentrations of carbonic anhydrase I (CAI) that reflect the integrated serum thyroid hormone concentration over the preceding few months. Furthermore, T3, at a physiological free concentration, decreases the CAI concentration in human erythroleukemic YN-1 cells. The effect of T3 on CAI concentration in burst-forming unit-erythroid (BFU-E)- derived cells, obtained by culturing peripheral blood mononuclear cells with various cytokines, including erythropoietin, has now been investigated. BFU-E-derived cells contained a high concentration of CAI (mean +/- SE, 4.8 +/- 0.8 x 10(-12) mol/10(6) cells; n = 8). The CAI in BFU-E-derived cells was immunologically identical to that present in mature red blood cells. T3 decreased the CAI concentration in BFU-E-derived cells in a dose-dependent manner (28%, 47% and 75% decreases at 3 x 10(-10), 1 x 10(-9), and 3 x 10(-9) mol/liter T3, respectively). These results suggest that BFU-E-derived cells may be used to study the effect of T3 on human red blood cell CAI. This system may prove useful in the tissue diagnosis of resistance to thyroid hormone.

Gene cloning and characterization of Pseudomonas putida L-methionine-alpha-deamino-gamma-mercaptomethane-lyase

Methionine dependency has been reported in cancer cell lines and primary tumors. Thus, L-methionine deprivation might have potential value for the treatment of human cancers with a methionine requirement. L-Methionine-alpha-deamino-gamma-mercaptomethane-lyase has been reported to decrease plasma methionine levels and to inhibit tumor growth in experimental animals but has not been studied extensively because sufficient homogeneous enzyme was not available. In this study, we cloned the L-methioninase gene from Pseudomonas putida and isolated pure and abundant recombinant enzyme. Both L-methionine and L-cysteine in culture medium were completely degraded by 1 unit/ml purified enzyme. Two hundred and fifty units/kg L-methioninase administered i.v. to mice yielded 0.7 unit/ml of plasma concentration and lowered total plasma sulfur-containing amino acids by more than 75%. Although sensitivity to enzymatic methionine depletion differed among cell lines, leukemia cell lines were generally more sensitive than solid tumor cell lines. The availability of pure recombinant L-methioninase will allow in vivo studies on the antitumor activity and the potential toxicity of enzymatic methionine depletion.

Immunolocalizations of human gelatinase (type IV collagenase, MMP-9) and TIMP (tissue inhibitor of metalloproteinases) in normal epidermis and some epidermal tumors

The matrix metalloproteinases (MMPs) MMP-2 and MMP-9 (gelatinases) have been suggested as serving an important role in cleaving the basement membrane structure. Tissue inhibitors of metalloproteinases TIMPs (particularly TIMP-1) are known to inhibit MMPs. Based on this background, we raised monoclonal antibodies against human gelatinase (MMP-9) and human recombinant TIMP (TIMP-1), and immunostained these two components in skin from patients with squamous cell carcinoma (SCC), Bowen's disease (BD) and keratoacanthoma (KA). MMP-9 showed positive staining mainly in the granular layer of normal epidermis. In some cases of SCC and BD, MMP-9 showed positive staining in the dysplastic lesions even in the basal layer. TIMP showed a thorough positivity in normal epidermis. Unstained regions with this antibody were observed in SCC and BD. These results suggest that an altered staining pattern for MMP-9 and TIMP may be closely related to the malignant transformation of SCC and BD.

EPR study of NO complex of bd-type ubiquinol oxidase from Escherichia coli

The heme axial ligands of bd-type ubiquinol oxidase of Escherichia coli were studied by EPR and optical spectroscopies using nitric oxide (NO) as a monitoring probe. We found that NO bound to ferrous heme d of the air-oxidized and fully reduced enzymes with very high affinity and to ferrous heme b595 of the fully reduced enzyme with low affinity. EPR spectrum of the 14NO complex of the reduced enzyme exhibited an axially symmetric signal with g-values at g = 2.041 and g = 1.993 and a clear triplet of triplet (or a triplet of doublet for the 15NO complex) superhyperfine structure originating from a nitrogenous proximal ligand trans to NO was observed. This EPR species was assigned to the ferrous heme d-NO complex. This suggests that the proximal axial ligand of heme d is a histidine residue in an anomalous condition or other nitrogenous amino acid residue. Furthermore, the EPR line shape of the ferrous heme d-NO was slightly influenced by the oxidation state of the heme b595. This indicates that heme d exists in close proximity to heme b595 forming a binuclear center. Another axially symmetric EPR signal with g-values at g(parallel) = 2.108 and g(perpendicular) = 2.020 appeared after prolonged incubation of the reduced enzyme with NO and was attributed to the ferrous heme b595-NO complex.

K-ras point mutations in cancerous and noncancerous biliary epithelium in patients with pancreaticobiliary maljunction

BACKGROUND

Pancreaticobiliary maljunction (PBM), an anomalous union of the pancreatic duct with the common bile duct, has frequently been shown to be associated with biliary carcinoma. However, the mechanism of carcinogenesis is unknown.

METHODS

Mutations of the K-ras oncogene were examined in cancerous and noncancerous biliary tract epithelium of 20 patients with PBM by an extraction of DNA from surgically resected histologic specimens. DNA was analyzed by a polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) method and direct sequencing.

RESULTS

An abnormally mobilized DNA band was detected not only in cancerous epithelium but also in hyperplastic, metaplastic, and inflammatory epithelium of the gallbladder and/or common bile duct in patients with PBM. Among the biliary epithelium of patients with PBM, point mutation of K-ras oncogenes were detected in 4 of 5 (80%) cancerous epithelium, 7 of 12 (58%) hyperplastic and metaplastic epithelium, and 8 of 18 (44%) inflammatory epithelium, whereas no point mutation of the K-ras oncogene was detected in the gallbladder epithelium in 3 control patients without PBM. Direct sequence analysis of the K-ras oncogene revealed the mutation at codon 12 substituting the wild-type glycine (GGT) for aspartic acid (GAT) in all cancerous lesions of patients with PBM. Simultaneous two-point mutations from the wild-type glycine (GGC) to arginine (CGC) at codon 13 associated with the mutation at codon 12 were also found in one case of gallbladder carcinoma and one case of bile duct carcinoma.

CONCLUSIONS

K-ras gene mutation is involved in the carcinogenesis of biliary tract epithelium in patients with PBM, and appears to be a high risk factor for carcinogenesis of the biliary tract.

Characterization of dp6troglycan-laminin interaction in peripheral nerve

Dystoroglycan is encoded by a single gene and cleaved into two proteins, alpha and beta-dystroglycan, by posttranslational processing. The 120kDa peripheral nerve isoform of alpha-dystroglycan binds laminin-2 comprised of the alpha 2, beta 1, and gamma 1 chains. In congenital muscular dystrophy and dy mice deficient in laminin alpha 2 chain, peripheral myelination is disturbed, suggesting a role for the dystroglycan- laminin interaction in peripheral myelinogenesis. To begin to test this hypothesis, we have characterized the dystroglycan-laminin interaction in peripheral nerve. We demonstrate that (1) alpha-dystroglycan is an extracellular peripheral membrane glycoprotein that links beta-dystroglycan in the Schwann cell outer membrane with laminin-2 in the endoneurial basal lamina, and (2) dystrophin homologues Dp116 and utrophin are cytoskeletal proteins of the Schwann cell cytoplasm. We also present data that suggest a role for glycosylation of alpha-dystroglycan in the interaction with laminin.

Comparison of Two Questionnaires on Respiratory Symptoms in a Nicaraguan Population: Value in Diagnosis of Chronic Bronchitis

Two questionnaires about respiratory symptoms were evaluated for reliability and ability to diagnose chronic bronchitis in a study population of 129 Nicaraguans (110 workers and 19 patients with chronic bronchitis). The first questionnaire (AQ) had symptom questions that were based on British Medical Research Council (MRC) questions, adapted to local Spanish. The second questionnaire (MRCQ) contained MRC symptom questions translated directly into Spanish. The reliability of the questions was measured in a test-retest procedure. The questionnaire-based diagnosis of chronic bronchitis was compared with the diagnosis made by a physician (for workers) or from the hospital records (for patients). The questions concerning symptoms in both questionnaires were of acceptable reliability. For the diagnosis of chronic bronchitis in workers, the AQ showed similar sensitivity, a somewhat higher specificity, and a substantially higher positive predictive value (90%) than the MRCQ (57%). Among the patients, the AQ identified 17 patients as positive (sensitivity 89%), while the MRCQ identified 15 (sensitivity 79%). respiratory questionnaire; reliability; chronic bronchitis; Nicaragua Hanley & Belfus, Inc. Int J Occup Environ Health 1077-3525 2 2 1996 April/June Chronic Exposure to Cigarette Smoke Inhibits the Stimulating Effects of Mineral Fibers on the Production of Tumor Necrosis Factor by Alveolar Macrophages of Rats 95 98 EN Yasuo Morimoto Department of Environmental Health Engineering, University of Occupational and Environmental Health, Japan 1-1, Iseigaoka, Yahatanishiku, Kitakyushu 807, Japan. Ziro Nambu Hajime Hori Tohru Tsuda Hiroshi Yamato Toshiaki Higashi Yasuyuki Yokosaki Masamitsu Kido Isamu Tanaka The objective of this study was to evaluate the chronic combined effects of mineral fibers and cigarette smoke on the production of tumor necrosis factor (TNF) by alveolar macrophages. The authors chronically exposed ten rats to cigarette smoke in vivo and measured the production of TNF by alveolar macrophages in the presence of mineral fibers in vitro. For smoke exposure, rats were divided into two groups. Five rats were exposed daily to a concentration of 10 mg/m(3) of cigarette smoke for six hours a day, five days a week, for four weeks, and five rats (control) were not exposed to smoke. A broncho-alveolar lavage was performed after the smoke exposure, and the recovered alveolar macrophages were incubated with either chrysotile or ceramic fibers on a microplate for 24 hours. TNF activity in the supernatant was determined by the L929 bioassay. When alveolar macrophages were not stimulated by mineral fibers, TNF production tended to be lower in smoke-exposed alveolar macrophages than in unexposed ones, although the difference was not significant statistically. When alveolar macrophages were stimulated in vitro by chrysotile or ceramic fibers, both fibers stimulated TNF production, but TNF production in smoke-exposed alveolar macrophages was lower than that in unexposed macrophages. These results revealed that long-term exposure to cigarette smoke inhibited the stimulating effect of mineral fibers on the production of TNF.

Infrared and EPR studies on cyanide binding to the heme-copper binuclear center of cytochrome bo-type ubiquinol oxidase from Escherichia coli. Release of a CuB-cyano complex in the partially reduced state

Cyanide-binding to the heme-copper binuclear center of bo-type ubiquinol oxidase from Escherichia coli was investigated with Fourier transform-infrared and EPR spectroscopies. Upon treatment of the air-oxidized CN-inhibited enzyme with excess sodium dithionite, a 12C-14N stretching vibration at 2146 cm-1 characteristic of the FeO3+ C=N CuB2+ bridging structure was quickly replaced with another stretching mode at 2034.5 cm-1 derived from the FeO2+ C=N moiety. The presence of ubiquinone-8 or ubiquinone-1 caused a gradual autoreduction of the metal center(s) of the air-oxidized CN-inhibited enzyme and a concomitant appearance of a strong cyanide stretching band at 2169 cm-1. This 2169 cm-1 species could not be retained with a membrane filter (molecular weight cutoff = 10,000) and showed unusual cyanide isotope shifts and a D2O shift. These observations together with metal content analyses indicate that the 2169 cm-1 band is due to a CuB.CN complex released from the enzyme. The same species could be produced by anaerobic partial reduction of the CN-inhibited ubiquinol oxidase and, furthermore, of the CN-inhibited cytochrome c oxidase; but not at all from the fully reduced CN-inhibited enzymes. These findings suggest that there is a common intermediate structure at the binuclear center of heme-copper respiratory enzymes in the partially reduced state from which the CuB center can be easily released upon cyanide-binding.

Cloning of the Mycoplasma capricolum gene encoding peptide-chain release factor

In Mycoplasma capricolum (Mc), a relative of Gram+ eubacteria with a high genomic A + T-content, the UGA codon is assigned to Trp instead of being a stop codon. We previously showed the lack of peptide-chain release factor (RF) activity in vitro responding to the UGA codon in this bacterium [Inagaki et al., Nucleic Acids Res. 21 (1993) 1335-1338]. To obtain more information on the translation termination mechanism of Mc, we isolated and sequenced the gene encoding RF. The deduced amino-acid sequence has no RF-2-specific + 1 frameshift site and shows 50 and 36% identity to Escherichia coli RF-1 and RF-2, respectively. We conclude that this gene encodes the putative RF-1 which would possess the conserved 'five-domain' structure of RF family found in various organisms.

Design and synthesis of new mitochondrial cytotoxin N-thiadiazolylanilines that inhibit tumor cell growth

New N-thiadiazolylanilines were designed and synthesized to develop mitochondrial cytotoxins superior to SF 6847. The mitochondrial cytotoxin N-thiadiazolylanilines, TX-108 and TX-109, inhibited EMT6/KU mammary sarcoma cell growth at a low micromolar concentration. Their inhibitory activities were parallel to their mitochondrial cytotoxicity, such as uncoupling oxidative phosphorylation and inhibiting ATP synthesis. This report also supports the notion that the inhibition of tumor cell growth of inhibitor of protein tyrosine kinase AG17, which is identical to SF 6847, may be due to its mitochondrial cytotoxicity.

Environmental tobacco smoke and policies for its control

This study evaluated the effect of designated smoking areas in an office and the efficacy of air cleaners in a smoking room. The concentrations of suspended particulates (SP) were measured at 13 points in the office, including the smoking room, corridors around the smoking room, and a non-smoking office. The SP concentrations were between 0.52 to 1.31 mg/m3 in the smoking room, 0.06 to 0.22 mg/m3 in the corridors and 0.03 to 0.05 mg/m3 in the non-smoking office, respectively. The results showed that the area restriction on smoking in this office was successful, although an outflow of tobacco smoke was observed in the corridors. The SP concentration in the smoking room where three electrostatic air cleaners had been installed was monitored over 24 hours. The SP concentration due to tobacco smoke in the smoking room was much greater than the control concentration of SP in air-conditioned buildings in Japan, that is, not more than 0.15 mg/m3. The effectiveness of electrostatic air cleaners in closed smoking rooms is discussed.

Effects of a factor derived from polymorphonuclear leukocytes on the growth and collagen metabolism in normal and scleroderma skin fibroblast cultures

Effects of a factor (15 kDa) derived from polymorphonuclear leukocytes (PMNs) on the growth and collagen metabolism of normal and scleroderma skin fibroblasts in culture were investigated. Skin fibroblasts from papillary, reticular or whole dermis of 5 patients with scleroderma and 7 normal controls were cultured in the presence or absence of PMN factor. The factor affected skin fibroblasts, (i) to stimulate cell proliferation, (ii) to stimulate collagenase production as observed by its functional activity, but (iii) to suppress collagen production with little effect on collagen types at a stage before the translational level. Scleroderma fibroblasts were less susceptible to the factor than normal fibroblasts in terms of cell proliferation and protein synthesis including collagen. Stimulation of cell proliferation by the factor was higher with reticular cells than papillary cells, while stimulation of collagenase production was inversely high in papillary cells and little stimulation was noted with reticular cells. Suppression of collagen production was also eminent in papillary cells, compared with that in reticular cells. These results suggest that PMNs function at the inflammatory stage in shifting tissue metabolism to a catabolic phase by releasing a factor which stimulates connective tissue cells, and that decreased susceptibility of scleroderma cells and reticular cells to PMN factor may provide for a positive factor in the accumulation of collagen in the reticular dermis of scleroderma skin.

Biochemical properties of the monomeric mutant of human cathepsin E expressed in Chinese hamster ovary cells: comparison with dimeric forms of the natural and recombinant cathepsin E

Cathepsin E (CE) is the only known aspartic proteinase that exists as a homodimer consisting of two fully catalytically active monomers, which are covalently bound by a disulfide bond between two cysteine residues at the NH2-terminal region (Cys43 in human pro-CE). To understand the physiological significance of the dimer formation, the monomeric mutant of human CE was constructed by site-directed mutagenesis (Cys43 ->Ser43) and expressed in Chinese hamster ovary (CHO) cells. Immunolocalization of the mutant protein at both the light and electron microscopic levels revealed the monomeric CE to be associated predominantly with the endoplasmic reticulum and the non-lysosomal endocytic organelles. The cellular localization of the monomeric protein was compatible with that of the wild-type (dimeric form) of recombinant human CE expressed in the same cells. The monomeric protein was generated primarily as the 46-kDa pro-CE with a high-mannose-type oligosaccharide chain in the cells. In addition to the maximal activation at around pH 3.5, a substantial proportion of the monomeric pro-CE was converted to the mature form by incubation at pH 7 and 37 degrees C for 5 min. In contrast, the dimeric pro-CE was scarcely activated by treatment at pH7. Although catalytic properties of the in vitro-activated monomeric CE appeared to be indistinguishable from those of the dimeric forms of natural and recombinant CE, the monomeric form was more unstable to pH and temperature changes than these dimeric forms. These results indicate that the dimerization of CE is not necessarily required for proper folding to express activity, correct intracellular localization and carbohydrate modification, but that it may be essential to structurally stabilize the molecule in vivo.