Characterization of monoclonal antibodies against (1R,2R)-cyclohexanediamine platinum(II)-DNA adduct

Two monoclonal antibodies raised against Pt(II)(1R,2R-cyclohexanediamine)-DNA were prepared, and the specificity of the monoclonal antibodies against Pt(II)(cyclohexanediamine)-DNA derivatives was determined by competitive enzyme-linked immunosorbent assay. The binding affinity of the monoclonal antibodies is apparently influenced by the cyclohexanediamine moiety of Pt(II)(cyclohexanediamine)-DNA adducts, but the monoclonal antibodies can not bind to the low molecular analogue, Pt(II)(1R,2R-cyclohexanediamine)-d(GpG), which is the intrastrand binding model compound of Pt(II)(1R,2R-cyclohexanediamine)-DNA. Therefore, the monoclonal antibodies recognize the macromolecular parts, including DNA duplex, in addition to the cyclohexane moieties of the platinum complexes on Pt(II)(cyclohexanediamine)-DNA adducts.

Structural analysis of the L-methionine gamma-lyase gene from Pseudomonas putida

The gene encoding L-methionine gamma-lyase from Pseudomonas putida was cloned and the primary structure of the enzyme was deduced from its nucleotide sequence. The L-methionine gamma-lyase gene was expressed in Escherichia coli. The amino acid sequences of BrCN-digested peptides agreed with the corresponding parts of the L-methionine gamma-lyase sequence determined from the gene structure. The polypeptide is composed of 398 amino acid residues with a calculated molecular weight of 42,626, corresponding to the subunit of the homotetrameric enzyme. The deduced amino acid sequence of L-methionine gamma-lyase only showed extensive homology with other well known alpha,gamma-elimination and/or gamma-replacement pyridoxal 5'-phosphate-dependent enzymes, such as cystathionine gamma-lyase, cystathionine gamma-synthase, and O-acetylhomoserine O-acetylserine sulfhydrylase, that participate in the biosynthesis of sulfur amino acids. However, the deduced essential cysteine residue of L-methionine gamma-lyase was not conserved in these enzymes. We confirmed the presence of a part of an open reading frame in the 3'-flanking region of the L-methionine gamma-lyase gene, which showed high homology with the N-terminal region of pyruvate dehydrogenase (lipoamide) from E. coli, suggesting that it participates in the degradative pathway for L-methionine together with L-methionine gamma-lyase.

[Castleman's lymphoma presenting marked bronchial obstruction and compression of the great vessels: a case report]

A 24-year-old Caucasian male from Chile developed mediastinal Castleman's lymphoma, hyaline-vascular type, occupying from upper pre-tracheal to sub-carinal region, severely compressing the trachea, left main bronchus, pulmonary artery, and pericardium. Bronchofiberscopy demonstrated complete obstruction of the left main bronchus and the severe telangiectasis of the mucosa. The patient complained of the stridor and shortness of breath. The left thoracotomy had been performed in Chile, but unsucceeded in extirpation because of the adherence and the hypervascularity of the tumor. After 24 Gy irradiation, we performed the right thoracotomy and succeeded in extirpation of the tumor. It was the key for success that we could approach from right side under left sided unilateral ventilation. Castleman's lymphoma is not a rare disease, but the manifestation due to the bronchial obstruction is uncommon. So we present this case and review the literatures.

Reaction of (1R,2S,3S)-3-methylcyclohexanediamineplatinum(II) with DNA: isolation and characterization of the platinum-nucleotide adducts by means of HPLC and NMR spectroscopy

Reaction products of calf thymus DNA with (1R,2S,3S)-3-methylcyclohexanediamineplatinum (abbreviated as Pt(RSS-dach)Cl2) were investigated by enzymatic degradation of the platinated DNA and subsequent HPLC analysis. Five platinated adducts involving d(GpG), d(ApG) and (dG)2 residues were identified by HPLC after complete digestion using deoxyribonuclease I, nuclease P1, and alkaline phosphatase. The adducts with d(GpG) and d(ApG) consisted of two geometrical isomers, because Pt(RSS-dach)Cl2 lacks a C2 symmetry element. The d(GpG) and d(ApG) adducts were intrastrand compounds crosslinked between the N7 atoms of the adjacent purine bases. The two d(GpG) adducts were most abundant and comprised more than 65% of all the platinated adducts. The relative ratio of the two d(GpG) isomers was 3:2 for reaction with DNA, whereas the ratio was 1:1 for reaction with a single stranded oligonucleotide. The detailed structure of the two d(GpG) adducts is also described based on NMR spectroscopic data.

Inhibition of tumor cell growth by low-boiling-point-saturated fatty acids isolated by molecular distillation and reversed phase liquid chromatography of hydrolysates of uncytotoxic wool grease secreted from sheep sebaceous gland

We showed that massive growth of mouse Ehrlich ascites carcinoma (EAC) cells was not inhibited by wool grease secreted from the sheep sebaceous gland, whereas wool fatty acids separated by saponification of wool grease was growth-inhibitory. We then fractionated wool fatty acids into 9 fractions using molecular distillation (80-200 degrees C; 1 x 10(-2) mmHg) and found a marked antitumor activity in a low-boiling-point (< 80 degrees C) fraction (MW 200-300; C10-C20), which was further separated by reversed phase liquid chromatography on an octadecylisilica gel column, resulting in 5 fractions. The second most hydrophobic fraction (C8Si-4) obtained was the most growth-inhibitory to EAC cells cultured or implanted into mice, more marked than the antitumor glycopeptide bleomycin. C8Si-4 was suggested to be a mixture of a normal-chain C16-saturated fatty acid and two branched-chain kinds of saturated C16-iso- and C19-anteiso-fatty acids without hydroxyl groups according to gas chromatography-mass spectrographic analysis. Thus low-boiling-point saturated fatty acid moieties in some wool grease molecules were shown to become growth-inhibitory in vitro and in vivo only after released in the free acid form by esterolysis.

Young children's naive theory of biology

This article aimed at investigating the nature of young children's naive theory of biology by reviewing a large number of studies conducted in our laboratories. More specifically, we tried to answer the following five critical questions. What components does young children's knowledge system for biological phenomena (or naive biology) have? What functions does it have in children's lives? How is it acquired in ontogenesis? How does its early version change as children grow older? Is it universal across cultures and through history? We propose that young children's biological knowledge system has at least three components, that is, knowledge needed to specify the target objects of biology, ways of inferring attributes or behaviors of biological kinds, and a non-intentional causal explanatory framework, and that these three constitute a form of biology, which is adaptive in children's lives. We also claim that the core of naive biology is acquired based on specific cognitive constraints as well as the general mechanism of personification and the resultant vitalistic causality, but it is differently instantiated and elaborated through activity-based experiences in the surrounding culture.

MEN type 1 associated with mediastinal carcinoid producing parathyroid hormone, calcitonin and chorionic gonadotropin

A 34-year-old Japanese woman was admitted to our hospital with a mediastinal tumor. Laboratory data showed high levels of calcitonin (CT), human chorionic gonadotropin (hCG) and parathyroid hormone (PTH) in the serum. Surgery was performed, but the tumor could not be completely resected. The patient died in the 10th postoperative month due to systemic metastasis and cachexia. At autopsy, diffuse parathyroid hyperplasia and multiple islet cell tumors of the pancreas were found. A pathological diagnosis of multiple endocrine neoplasia (MEN) type 1 associated with mediastinal atypical carcinoid tumor was made. Immunohistochemical study indicated the tumor cells of the mediastinum to be positively stained for hCG beta but not for PTH or CT. The tumor tissue contained significantly high levels of CT, PTH and whole hCG. This is the first case report on MEN type 1 associated with mediastinal carcinoid tumor producing PTH, CT and hCG beta.

Transformation of the acidophilic heterotroph Acidiphilium facilis by electroporation

We constructed a cloning vector for use in the acidophilic heterotroph Acidiphilium facilis. The vector pAH101 (8.8 kb) was constructed from a 6.1 kb restriction fragment of the Acidiphilium plasmid pAH1 and a pUC19 carrying a beta-lactamase gene. The antibiotic resistance gene was efficiently expressed in A. facilis. Several factors which influenced the transformation efficiency were optimized, resulting in a transformation efficiency of up to 3 x 10(3) transformants per microgram of plasmid DNA at a field strength of 10 kV/cm with a 7.0 ms pulse.

Young children's understanding of the mind-body distinction

A experiments investigated children's understanding of the mind-body distinction. Children of ages 4 and 5 recognized not only the differential modifiability of changeable versus unchangeable human properties and bodily versus mental properties, but also the independence of activities of bodily organs from a person's intention (Experiment 1). When presented 3 types of causal explanations (i.e., intentional, vitalistic, mechanical), 6-year-olds chose most often as most plausible for bodily functions vitalistic explanations (i.e., those ascribing the phenomena to a relevant bodily organ's initiative and effortful engagement in activity); 8-year-olds chose the vitalistic explanations second most often, following mechanical ones (Experiment 2). However, 6-year-olds, as well as 8-year-olds and adults, did not always choose vitalistic explanations over intentional explanations (Experiment 3); whereas they tended to prefer vitalistic explanations for biological phenomena, they predominantly accepted intentional ones for psychological phenomena (Experiment 3A). These results suggest that children as young as 6 years of age have acquired a form of biology as an autonomous domain which is separate from that of psychology.

Restriction endonuclease Aor13HI from Acidiphilium organovorum 13H, a new isoschizomer of BspMII: purification and characterization

A restriction endonuclease, Aor13HI, an isoschizomer of BspMII, was purified to homogeneity from cell extracts of Acidiphilium organovorum strain 13H. The enzyme has a molecular mass of 60,000 daltons and consists of two subunits identical in molecular mass of 30,000 daltons. Aor13HI endonuclease, like BspMII, recognizes the palindromic six-base sequence 5'-TCCGGA-3', and cleaves between the T and C to produce a four-base 5' extension. Aor13HI is not inhibited by dam-dependent methylation. The isoelectric point of the enzyme is 5.7. Aor13HI activity was maximum at pH 7.5, 100 mM KCl, 7.5-10 mM MgCl2, and 55 degrees C. The enzyme was stable up to 60 degrees C. The N-terminal amino acid sequence (30 residues) of Aor13HI did not show any similarity with the sequence of other restriction endonucleases reported.

3-Isopropylmalate dehydrogenase from chemolithoautotroph Thiobacillus ferrooxidans: DNA sequence, enzyme purification, and characterization

3-Isopropylmalate dehydrogenase encoded by the Thiobacillus ferrooxidans leuB gene was purified to homogeneity from Escherichia coli cells harboring a recombinant plasmid containing the leuB gene. The native enzyme molecule is a dimer of molecular weight 38,000. The Km value for 3-isopropylmalate was estimated to be 26 microM and that for NAD+ 0.8 mM. The presence of K+ or NH4+ is essential for the enzyme reaction. The enzyme is activated about 4-fold by the addition of 1.0 mM Mg2+ or Co2+. The optimum pH and temperature for the activity are 9.0 and 60 degrees C, respectively. The properties of the enzyme are similar to those of the Salmonella typhimurium and Thermus thermophilus enzymes, except for substrate specificity. T. ferrooxidans 3-isopropylmalate dehydrogenase is able to utilize D- and L-malate as substrates in addition to 3-isopropylmalate. Sequencing of subcloned DNA revealed that the leuB gene consists of a 1,074 bp open reading frame and encodes 358 amino acid residues corresponding to the subunit (38,462 Da). The amino acid sequence of 3-isopropylmalate dehydrogenase from T. ferrooxidans and those of some heterotrophic microorganisms have high homology.

Bacteriological investigation of bile in patients with cholelithiasis

The microflora in bile from the gallbladder and common bile duct was investigated in 303 patients who underwent surgery for cholelithiasis. The purpose of this study was to identify current bacteria and bacterial casts in the biliary tract and also to analyze the relationship between bactericholia at the time of operation and postoperative infection. Bile cultures were positive in 38% of all patients, although a higher incidence of positive bile cultures occurred in patients over 70 years of age (77%), those with common duct stones (83%), those with pigment stones (65%), and those who underwent gastrectomy (71%). The predominant organisms were Escherichia coli (22%), Klebsiella (18%), and Enterococcus (15%). Obligate anaerobes were less frequently seen (4%), being found only in patients with pigment stones and always mixed with aerobes. Four patients developed postoperative infections (1.3%) which were all caused by biliary bacteria. The following two factors may contribute to this low incidence of postoperative infections: our policy of operating electively whenever possible, and the prophylactic use of antibiotics to which the organisms cultured from bile are sensitive.

Chemical compatibility of cefmetazole sodium with ranitidine hydrochloride during simulated Y-site administration

The stability of cefmetazole sodium and ranitidine hydrochloride was studied under conditions simulating administration via a Y-injection site into a primary infusion line. Cefmetazole sodium was reconstituted with both 0.9% sodium chloride injection (50 mL or 100 mL) and 5% dextrose injection (50 mL) to produce premixing concentrations of cefmetazole 10 and 20 mg/mL. Ranitidine hydrochloride injection was diluted with 50 mL 0.9% sodium chloride injection to give premixing concentrations of ranitidine 1 mg/mL. To simulate Y-site administration, 2 mL of cefmetazole was mixed with 2 mL of ranitidine in a 10-mL glass test tube. All study mixtures were prepared in triplicate and stored at room temperature (22-23 degrees C) under normal fluorescent room lighting. Samples of these admixtures were inspected for visual changes and tested for pH. The concentrations of two drugs were immediately determined by stability-indicating high-performance liquid chromatographic assay methods after mixing and at 1, 2, and 4 hours. No visual changes were observed. The pH in the admixtures was influenced by concentrations of the two drugs. The pH of each single-drug solution did not change during the study period. On the other hand, the pH of any admixtures of cefmetazole and ranitidine solutions prepared with 0.9% sodium chloride or 5% dextrose injection, decreased. Cefmetazole in any of the admixtures with ranitidine retained greater than 95% of its original concentration for 4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

[Detection of mediastinal lymph node metastasis from lung cancer with positron emission tomography (PET) using 11C-methionine]

Twenty-five patients with primary non-small cell lung cancer underwent the positron emission tomography (PET) using 11C-methionine to detect the mediastinal lymph node metastasis. We introduced the positron angiography to recognize precisely the anatomical orientation of the mediastinal lymph nodes. The 11C-uptake of the lymph node was expressed with distribution absorption ratio (DAR). A total 107 lymph nodes were examined. The average DAR in metastatic lymph nodes (n = 28) was 3.89 while that of non-metastatic nodes (n = 79) was 2.38 indicating a significant difference (p < 0.001). The most adequate threshold for detection of metastasis was 3.3 with sensitivity of 100%, and specificity of 87.3% and overall accuracy of 89.7%. Metastasis of squamous cell carcinoma was diagnosed more accurately than that of adenocarcinoma. Thus, PET using 11C-methionine may offer a new method to detect the mediastinal lymph node metastasis from lung cancer.

Stability of ranitidine hydrochloride with aztreonam, ceftazidime, or piperacillin sodium during simulated Y-site administration

The stability of ranitidine hydrochloride after being mixed with commonly used i.v. beta-lactam antibiotics and administered by simulated Y-site injection was studied. Solutions of ranitidine 1 mg/mL (as the hydrochloride salt), aztreonam 16.7 mg/mL, ceftazidime 20 mg/mL (with sodium carbonate), and piperacillin 30 mg/mL (as the sodium salt) were prepared by reconstitution in i.v. mini-bags. To simulate Y-site injection, 2 mL of ranitidine hydrochloride was mixed with 2 mL of each antibiotic in glass test tubes. These admixtures were prepared in triplicate and stored at room temperature under fluorescent light. Concentrations of each drug in each admixture were determined by stability-indicating high-performance liquid chromatography immediately and after one, two, and four hours. Aztreonam, ceftazidime, and piperacillin each retained more than 95% of the original concentration for at least four hours when mixed 1:1 with ranitidine. Ranitidine retained more than 90% of its original concentration for at least four hours when combined with each of the other drugs. Ranitidine 1 mg/mL (as the hydrochloride salt) and aztreonam 16.7 mg/mL, ceftazidime 20 mg/mL (with sodium carbonate), or piperacillin 30 mg/mL (as the sodium salt) were stable for at least four hours during simulated Y-site administration.

Cytosolic and intranuclear calcium signals in rat basophilic leukemia cells as revealed by a confocal fluorescence microscope

A confocal fluorescence microscope with an argon-ion laser (488 nm) and a He-Cd laser (325 nm) was used to study spatial heterogeneity of the calcium signals in rat basophilic leukemia 2H3 cloned cell line (RBL-2H3). After stimulation with antigen (2,4-dinitrophenol-conjugated bovine serum albumin), fluo-3-fluorescence intensities increased in individual RBL-2H3 cells with different lag times. Time-dependent profiles of the fluo-3-fluorescence intensities resembled closely the patterns of the sequential fluorescence-ratio images of fura-2, which were used to measure the intracellular free-calcium concentration ([Ca2+]i) in individual RBL-2H3 cells using a conventional fluorescence microscope. The present results obtained using the confocal fluorescence microscope showed spatial heterogeneities of fluo-3-fluorescence intensities, suggesting the existence of spatial heterogeneity of [Ca2+]i in RBL-2H3 cells. That is, the results showed that calcium signals first occurred transiently at pseudopodia in RBL-2H3 cells, then the signals transferred to the central parts of the cells. In addition, from the fluorescence images of co-loaded Hoechst 33342 (bisbenzimide H 33342, a DNA-specific probe) which were produced by excitation with a He-Cd laser, it was found that the fluorescence images of the nucleus were quite similar to those of the calcium signals mentioned above. This suggested that the receptor-mediated calcium signals were transferred not only to the cytoplasm but also to the nucleus.

A fluorescent molecular rotor probes the kinetic process of degranulation of mast cells

A confocal fluorescence microscope was used to study the exocytotic secretory processes of mast cells in combination with an fluorescent molecular rotor, 9-(dicyanovinyl)julolidine (DCVJ). DCVJ is known to be an unique fluorescent dye which increases its quantum yield with decreasing intramolecular rotation. Here, DCVJ-loaded peritoneal rat mast cells were stimulated with compound 48/80 and their fluorescence images were compared with fluorescence calcium images of fluo-3-loaded mast cells. Subsequent to transient increases in intracellular free calcium ion concentration, DCVJ fluorescence increased dramatically in the cytoplasm and formed a ring-like structure around the nucleus, suggesting the possibility that the dye bound to the proteins composing the cytoskeletal architecture. Furthermore, the increases of DCVJ fluorescence intensities were mostly blocked in the presence of cytochalasin D (10 microM). However, fluo-3 fluorescence intensities still increased after addition of compound 48/80.