Purification, characterization, and crystallization of two types of lipase from Rhizopus niveus

The purification and some properties of two types of lipase (Lipase I and Lipase II) from Rhizopus niveus are described. The enzymes were purified to homogeneity by column chromatographies on DEAE-Toyopearl (1 pass) and CM-Toyopearl (2 passes). Lipase I consists of two polypeptide chains [a small peptide with sugar moiety (A-chain) and a large peptide of molecular weight 34,000 (B-chain)]. Lipase II has a molecular weight of 30,000 consisting of a single polypeptide chain. Lipase I appeared to be converted to Lipase II by limited proteolysis by a specific protease a small amount of which is in the culture supernatant from Rh. niveus, because one of the peptides formed has the same N-terminal sequence and C-terminal amino acid as Lipase II, as well as the molecular mass estimated by SDS-PAGE. Lipase I had a pH optimum of 6.0-6.5 and a temperature optimum of 35 degrees C, while, for Lipase II these values were pH 6.0 and 40 degrees C. Both enzymes were obtained in the crystalline state using the hanging drop method of vapor diffusion and PEG as the precipitating agents.

Epitope mapping of bovine serum albumin using monoclonal antibodies coupled with a photoreactive crosslinker

Antigenic determinants (epitopes) on bovine serum albumin (BSA) to anti-BSA monoclonal antibodies (mAbs) were assessed by means of photoaffinity labeling. Anti-BSA mAbs, AB3 and AB6, were modified with an 125I-labeled photoreactive crosslinker, sulfosuccinimidyl 2-(p-azidosalicylamido)ethyl-1,3'-dithiopropionate (SASD) and then bound with BSA. The complex yielded was irradiated with UV light to facilitate covalent binding of the modified mAb with BSA. Reduction of the product with 2-mercaptoethanol revealed that radioactivity of 125I-SASD was specifically introduced into BSA, probably near the mAb combining site(s). The radiolabeled or native BSA was digested with V8 protease and the peptides produced were assessed for their amino acid sequence, the radiolabeled amino acids contained, and their reactivity to mAb. The results indicated that AB3 mAb recognized an epitope in the region of Ala-537 to Asp-554 on a linear part of the BSA molecule, whereas AB6 mAb probably recognized an epitope of the assembled form present in a peptide of Asp-299 to Glu-338.

Intravascular bronchioloalveolar tumor with skin metastases

Intravascular bronchioloalveolar tumor (IVBAT) is a rare pulmonary tumor that occurs in the younger age groups. In the present article, we describe a patient who manifested systemic growth after the resection of the primary tumor. Skin metastasis, which has never been reported, is histologically examined.

[Chemical control of gene expression]

Expression of specific genes can be controlled by some compounds (gene expression modifiers) which can be divided into two categories, i.e.; (a) compounds which directly bind to nucleic acids having specific sequences and (b) compounds which bind specific transcription factors (including nuclear receptors) or related factors. Recent results on the structural development and mechanistic studies into the gene expression modifiers, mainly retinoids, phorbol ester, hemin, antisense molecules, and thalidomide analogs, have been reviewed. Some of these gene expression modifiers elicit cell differentiation inducing, tumor promoting, and biological response modifying activities. Development of more potent and/or more specific gene expression modifiers might be useful in cancer chemotherapy.

[Effect of epinephrine added to spinal anesthesia with lidocaine and tetracaine]

The effect of epinephrine added to the solution of lidocaine and tetracaine for spinal anesthesia was investigated in patients undergoing elective surgery of lower extremities. Thirty patients received 3ml of 2% lidocaine and 0.4% tetracaine and 30 patients received the solution with 0.1 mg of epinephrine added. A lumbar puncture was performed at the L2-3 interspace, using a midline approach with a 25-gauge spinal needle. Mean highest level of pinprick analgesia was Th6.1 without epinephrine and Th4.4 with epinephrine, and mean time for regression to Th10 was 2.3 hours without epinephrine and 3.6 hours with epinephrine. Progression of analgesia level was significantly faster and prolongation of duration was significant greater after adding epinephrine. No severe complications were found in any patients. We concluded that adding 0.1 mg of epinephrine to 3 ml of 2% lidocaine and 0.4% tetracaine could produce clinically useful prolongation of spinal analgesia.

Analysis of AP-1 function in cellular transformation pathways

To understand the role of endogenous AP-1 activity in cellular transformation induced by oncogenes, we have made use of a fos mutant (supfos-1) and a jun mutant (supjun-1), either of which can function as a transdominant inhibitor of AP-1-mediated transcriptional regulation. Chicken embryo fibroblasts (CEF) infected with a series of transforming retroviruses were doubly infected with retrovirus carrying supfos-1 or supjun-1, and suppression of cellular transformation was monitored in terms of reversion to normal cellular morphology or acquisition of anchorage-dependent growth. Cellular transformation induced by several exogenously expressed transforming genes of the fos or jun family was efficiently suppressed, as expected. CEF transformed by v-src, v-yes, v-fps, c-Ha-ras, and N-terminally truncated c-raf were also induced to revert to the normal phenotype by these transdominant mutants, suggesting that functional transcription factor AP-1 activity is essential for the cellular transformation induced by these oncogenes. The suppression is not attributable to nonspecific inhibition of cellular proliferation, because CEF transformed by v-ros or v-myc were not induced to revert to the normal phenotype. We next analyzed changes in all known components of chicken AP-1 induced by v-src, c-Ha-ras, or activated c-raf transformation. The levels of both Fra-2 and c-Jun expression were elevated two- to fourfold, and hyperphosphorylation of Fra-2 was also observed. We further showed that Fra-2-c-Jun heterodimer is mainly responsible for the elevated AP-1 DNA-binding activity in these transformed cells, and we propose that this heterodimer play a crucial role in the transformation induced by these oncogenes.

Comparative studies on Borrelia afzelii isolated from a patient of Lyme disease, Ixodes persulcatus ticks, and Apodemus speciosus rodents in Japan

The genospecies Borrelia afzelii was isolated from a patient of Lyme disease in Hokkaido, Japan, for the first time, by culturing the minced erythema lesion in BSK II medium. Two analytical methods, rRNA gene restriction fragment length polymorphism (RFLP) and polymerase chain reaction (PCR) using the specific primer set to amplify the 16S rRNA gene, revealed that this clinical isolate belongs to the group of B. afzelii. In our culture collection of spirochetes, part of the isolates from Ixodes persulcatus ticks, and from Apodemus speciosus rodents, were also classified as B. afzelii. These results strongly suggest that the agent pathogenic to humans is maintained in "rodent-tick" transmission cycle.

Characterization of a cytotoxic factor produced by rat bladder cancer cell line: its identity to TNF alpha

Clone C19 derived from a rat bladder cancer cell line BC31ad constitutively released cytotoxic factor RCF. The serum-free C19-conditioned medium was partially purified by DEAE-Sephacel, Sephacryl S-200 and MonoQ-FPLC chromatographies to the specific activity of 6.4 x 10(6) U/mg protein (LM assay). RCF was a 17-kDa protein with pI 4.6-5.0. Anti-RCF serum neutralized the cytotoxic activity of rat and mouse, but not human, tumor necrosis factor-alpha (TNF alpha) as well as RCF. The partial amino acid sequence of RCF was homologous with the sequence 43-58 of rat TNF alpha. RCF and rat TNF alpha showed a similar cytotoxic spectrum against several tumor cells. Furthermore, they induced a marked proliferation of mouse T cells in combination with a suboptimal dose of ConA or anti-CD3 antibody, however, human TNF alpha almost not. Taken together, RCF was substantially regarded as rat TNF alpha.

Alterations of specific and nonspecific binding of monoclonal antibody by introduction of acidic and hydrophobic groups

AB-6 monoclonal antibody (mAb) against bovine serum albumin (BSA) was coupled with beta-alanine or n-propylamine using a heterobifunctional cross-linking reagent, N-(epsilon-maleimidocaproyloxy)succinimide (EMCS) and a linker, poly-L-cysteine to introduce acidic or hydrophobic groups into the mAb. The mAb molecules coupled with beta-alanine at lower than 1:16 molar ratios and those coupled with n-propylamine at 1:14 retained the original reactivity to BSA but modification with higher amounts of beta-alanine or n-propylamine decreased the reactivity. In contrast, nonspecific bindings of AB-6 mAb to a plastic culture plate and tumor (MDA-MB-453) cells were decreased by modification with beta-alanine and increased by n-propylamine. These results suggested that introduction of acidic groups, and hydrophobic groups to antibody leads to fluctuations in the non-specific binding of antibody.

Protein kinase C-dependent and -independent mechanisms of dense granule exocytosis by human platelets

We examined the mechanisms of ATP release by human platelets using Ro-31-7549, a specific inhibitor of protein kinase C. Ro-31-7549 almost completely inhibited TPA-induced platelet aggregation and ATP release at 5-10 microM in washed platelets and in platelet-rich plasma. However, it suppressed thrombin- and U46619-induced ATP release by only 48% and 21%, respectively, and had little effect on aggregation in washed platelet suspensions containing serum or in platelet-rich plasma. The addition of GRGDS to prevent aggregation inhibited this residual thrombin-induced release by 53% and the residual U46619 release by 100% in the presence of Ro-31-7549. In washed platelet suspensions free of serum or plasma, Ro-31-7549 almost completely inhibited the ATP release and partially suppressed the aggregation induced by these agonists. These results suggested that there are protein kinase C-dependent and -independent mechanisms for ATP release by human platelets and that activation of the latter mechanism may depend on aggregation and plasma factors.

Retinobenzoic acids. 6. Retinoid antagonists with a heterocyclic ring

Several candidate retinoid antagonists were designed on the basis of the ligand superfamily concept and synthesized. Retinoidal activities of these benzimidazole and benzodiazepine derivatives were examined by assay of differentiation-inducing activity on human promyelocytic leukemia cell line HL-60. The parent benzimidazole derivative, 4-(5,6,7,8-tetrahydro-5,5,8,8- tetramethylnaphth-[2,3-d]imidazol-2-yl)benzoic acid (7a), and related compounds with a small alkyl group instead of the hydrogen on the nitrogen (1N) atom of the imidazole ring exhibited retinoidal activity, and the potency strongly depended on the bulkiness of the substituent. The compounds having a phenyl or benzyl group on the nitrogen lacked differentiation-inducing activity on HL-60 cells and acted as antagonists to the potent retinoid 4-[(5,6,7,8-tetrahydro-5,5,8,8- tetramethyl-2-naphthalenyl)carbamoyl]benzoic acid (Am80). Among the compounds possessing a seven-membered heterocyclic ring as a linking group, 4-(5H-7,8,9,10-tetrahydro-5,7,7,10,10- pentamethylbenzo[e]- naphtho[2,3-b][1,4]diazepin-13-yl)benzoic acid (16) also exhibited the antagonistic activity. The binding abilities of these compounds to retinoic acid receptors alpha and beta were consistent with their potency for the inhibition of HL-60 cell differentiation induced by the retinoid Am80.

Binding of serum albumin on tumor cells and characterization of the albumin binding protein

The binding of bovine (BSA) and human serum albumin (HSA) to the surface of human and mouse tumor cells in vitro was examined by flow cytometry using monoclonal antibodies against these albumins. Both isologous and heterologous types of albumin bound firmly on several lines of human and mouse tumor cells. The cell-bound albumin was removable by protease (actinase) treatment or by culture in albumin-free medium for more than 2 days, but not by simple washing. The amount of albumin capable of binding to the tumor cell surface differed among the 9 tumor cell lines tested. As determined with radioiodinated BSA, about 2.6 x 10(6) BSA molecules/cell could bind to MDA-MB-453 human mammary cancer cells, which exhibit high binding capacity as to BSA. A unique peptide having a molecular weight of 18 kDa was detected on gel electrophoresis in extracts of tumor cells or normal aortic endothelial cells which had been treated with radioiodinated, photocross-linker-labeled BSA or HSA, followed by UV-irradiation. This peptide was also immuno-precipitated with an anti-BSA or anti-HSA monoclonal antibody. With both methods, the yield of the peptide was decreased by previous addition of an excess amount of unlabeled BSA or HSA. These findings indicated that the 18-kDa peptide expressed on both normal aortic endothelial cells and tumor cells is a principal serum albumin-binding protein, and that this protein binds both BSA and HSA.

Increase in the chemically-induced differentiation of human leukemia cell lines by tubulin disruptors

The effect of various structural/functional tubulin disruptors (including colchicine-type disruptors, vinblastine, rhizoxin, maytansine, peptide-type disruptors, and taxol) on the chemically induced differentiation of human leukemia cell lines (HL-60 and K562) was examined. As differentiation-inducing agents, 12-O-tetradecanoylphorbol-13-acetate (TPA) was used for the differentiation of both HL-60 and K562 to monocyte/macrophages, retinoids were used for the differentiation of HL-60 to mature granulocytes, and hemin was used for the erythroid differentiation of K562. All the tubulin disruptors investigated increased the chemically-induced differentiation of HL-60 and K562 cell lines to the cognate mature cell types, regardless of the nature of the differentiation.

Isolation and characterization of a novel hair follicle-specific gene, Hacl-1

We have isolated a hair-follicle-specific gene, termed hacl-1, from a cDNA library of ICR mouse skin. Hacl-1 is expressed specifically in skin, and its mRNA level is correlated with the active state of hair follicles in developmental and regenerative processes of hair. Its mRNA is approximately 1 kilobase pairs (kb). Its cDNA was completely co-linear with the genomic clone, indicating that the hacl-1 gene is composed of one exon. The hacl-1 gene has an open reading frame of 579 base pairs (bp). The deduced amino acid sequence showed six direct repeats of a decapeptide on the C-terminal side. The repetitive unit contains a CQP motif, which is present in repetitive peptide sequences of some hair- and epidermal-cell-specific proteins. In situ hybridization with a 3' untranslated region of the hacl-1 cDNA as a probe showed that hacl-1 was expressed specifically in the keratogenous zone of the cortical cells of the hair shaft. No other components of hair follicles or epidermis showed a positive signal. Thus, hacl-1 is a novel, hair-follicle-specific gene.

Pre-Kupffer like CD4/CD8 double positive mononuclear cells present in rat liver

Nonparenchymal cells isolated from Fischer rat liver were separated into subpopulations by passage through a nylon wool column and/or culturing in a plastic plate. Besides typical Kupffer cells, we detected a unique population of cells (called PKu cells) which were plastic adherent but did not spread on a short term culture, were nonadherent on nylon wool, and were nonphagocytic, as opposed to Kupffer cells. Both Kupffer cells and PKu cells expressed CD4 (recognized with W3/25 mAb), CD8 (OX-8), a NK cell antigen (3.2.3), and a monocyte antigen (OX-41), as assessed by flow cytofluorometry. However, the proportion of cells bearing high densities of CD8 and 3.2.3 antigens was much larger for PKu cells than for Kupffer cells. Reverse transcriptase-PCR analysis of CD8 mRNA revealed that PKu cells expressed the CD8 alpha chain but not the beta chain. When PKu cells were treated with phorbol 12-myristate 13-acetate (PMA), they exhibited spreading and phagocytic activities, and showed a similar morphology to Kupffer cells in the spread form. Moreover, PMA treatment decreased the high density of CD8 antigen on PKu cells. These findings indicated that PKu cells present in normal rat liver are precursors of Kupffer cells.

(S)-form of alpha-methyl-N(alpha)-phthalimidoglutarimide, but not its (R)-form, enhanced phorbol ester-induced tumor necrosis factor-alpha production by human leukemia cell HL-60: implication of optical resolution of thalidomidal effects

The rate of racemization of N(alpha)-phthalimidoglutarimide (thalidomide) was determined as its half life to be 566 min at pH 7.4/37 degrees C. This fast racemization of thalidomide resulted in no apparent difference between (S)- and (R)-forms of the compound on enhancing activity of phorbol ester-induced tumor necrosis factor (TNF)-alpha production by human leukemia HL-60 cells. Optically pure forms of structurally related analog of thalidomide, (S)- and (R)-alpha-methyl-N(alpha)-phthalimidoglutarimides (methylthalidomides), which do not racemize under the physiological condition, were prepared. Only (S)-form of methylthalidomide, but not its (R)-form, elicited TNF-alpha production-enhancing effect, suggesting that the (S)-isomer of thalidomide would be the active form in terms of thalidomidal biological response modifying effects.

The network properties of bipolar-bipolar cell coupling in the retina of teleost fishes

Retinal bipolar cells exhibit a center-surround antagonistic receptive field to a light stimulus (Werblin & Dowling, 1969; Kaneko, 1970), and thus constitute an early stage of spatial information processing. We injected Lucifer Yellow and a small biotinylated tracer, biocytin, into bipolar cells of the teleost retina to examine electrical coupling in these cells. Lucifer-Yellow coupling was observed in one of 55 stained bipolar cells; the coupling pattern was one injected bipolar cell and three surrounding cells. Biocytin coupling was observed in 16 of 55 stained bipolar cells, six of which were ON center and ten OFF center. Although biocytin usually coupled to three to six bipolar cells, some OFF-center bipolar cells showed strong coupling to more than 20 cells. The biocytin-coupled bipolar cells were morphologically homologous. Membrane appositions resembling gap junctions were found between dendrites and between axon terminals of neighboring bipolar cells. In the strongest biocytin-coupled bipolar cells, the contacts between bipolar cells and cone photoreceptor cells were examined after reconstruction of the dendritic trees of five well-stained, serially sectioned OFF-center bipolar cells. Each of these bipolar cells was in contact with different numbers of cones: 11 to 20 for twin cones and two to four for single cones. This implies that, although these bipolar cells belong to the same category, the signal inputs differ among bipolar cells. Numerical simulation conducted on a hexagonal array network model demonstrated that the electrical coupling of bipolar cells can decrease the difference in input (approximately 80%) without causing significant loss of spatial resolution. Our results suggest that electrical coupling of bipolar cells has the advantage of decreasing the dispersion of input signals from cones, and permits bipolar cells of the same class to respond to light with similar properties.

Ionic lead, a unique metal ion as an inhibitor for cytochrome P450IA2 (CYP1A2) expression in the rat liver

Male F344 rats were treated with lead nitrate, nickel chloride, cobalt chloride or cadmium chloride, and changes in the expression of cytochrome P450IA2 (CYP1A2) in the livers were assessed by enzymatical, immunochemical, and molecular biological methods. All ionic metals used significantly decreased total CYP amount in the liver microsomes. However, among ionic metals used only lead showed inhibitory effects on the microsomal activity for CYP1A2-dependent mutagenesis of aromatic amines and on the expression of mRNA and protein of the enzyme, indicating that ionic lead is a unique inhibitor for the expression of CYP1A2 enzyme in the rat liver.

DNA adduct formation of hepatocarcinogenic aromatic amines in rat liver: effect of cytochrome P450 inducers

F344 rats were treated with an i.p. injection of 2-amino-6- methyldipyrido[1,2-a:3',2'-d]imidazole (Glu P-1) or 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and examined for the formation of the DNA adduct in the liver. To examine the effect of pretreatment with a cytochrome P450 (CYP) inducer on the formation of DNA adduct, these rats were pretreated with 3-methylcholanthrene (MC; CYP1A1/1A2 inducer) or phenobarbital (PB; CYP2B inducer). Administration of Glu P-1 and 3-MeO-AAB gave 2 and 5 adducts, respectively, as determined by 32P-postlabeling assay. By Glu P-1 administration, pretreatment of rats with MC, but not with PB, increased the total amount of DNA adducts including 3 new adducts as minor products. In contrast, pretreatment of rats with PB increased the total amount of DNA adducts derived by 3-MeO-AAB. The increase of aromatic amine DNA adducts by pretreatment with a CYP inducer was proportional to the activity of induced CYP isozyme(s) responsible for the mutagenic activation of each aromatic amine.

C3G, a guanine nucleotide-releasing protein expressed ubiquitously, binds to the Src homology 3 domains of CRK and GRB2/ASH proteins

CRK protein, together with GRB2/ASH and Nck proteins, belongs to the adaptor-type Src homology (SH)2-containing molecules, which transduce signals from tyrosine kinases. Here another guanine nucleotide-releasing protein (GNRP), C3G, has been identified as a CRK SH3-binding protein. The nucleotide sequence of a 4.1-kb C3G cDNA contains a 3.2-kb open reading frame encoding a 121-kDa protein, and antibodies against C3G have been shown to detect a protein of 130-140 kDa. The carboxyl terminus of C3G has a peptide sequence homologous to GNRPs for Ras, and the expression of this carboxyl terminus region suppresses the loss of CDC25 function in the yeast Saccharomyces cerevisiae. The C3G protein expressed in Escherichia coli binds to CRK and GRB2/ASH proteins. Mutational analysis of C3G assigns the SH3 binding region to a 50-amino acid region containing a proline-rich sequence. The mRNAs of both the C3G and CRK proteins are expressed ubiquitously in human adult and fetal tissues. The results of these studies suggest that the complex of CRK and C3G, or GRB2/ASH and C3G, may transduce the signals from tyrosine kinases to Ras in a number of different tissues.

Anatomical and histological re-examination of Appendices colli in the goat

Appendices colli (App. colli) were investigated by anatomical and histological methods in the goat. App. colli were composed of elastic cartilage located at central and the skin covering the cartilage, which included arterioles along the cartilage and nerve bundles. Three types of muscles connected to App. colli; superficial muscle bundles, a branch of the omohyoideus muscle, and a muscle arising from the pharyngeal raphe (appendico-pharyngeal muscle). The latter two muscles were connected to the root of the App. colli where the muscle fibers transformed into the perichondrium of the elastic cartilage. The appendico-pharyngeal muscle was innervated by branches from the glossopharyngeal nerve which were composed of myelinated nerve fibers. The subcutaneous area of the App. colli was supplied by cutaneous rami of the vagus and the second cervical nerves. The innervation and the musculature confirmed that the cartilage of the App. colli were derived from third and fourth branchial arches.

Simulation for the analysis of distorted pharmacodynamic data

A simulation study was conducted to compare the performance of alternative approaches for analyzing the distorted pharmacodynamic data. The pharmacodynamic data were assumed to be obtained from the natriurertic peptide-type drug, where the diuretic effect arises from the hyperbolic (Emax) dose-response model and is biased by the dose-dependent hypotensive effect. The nonlinear mixed effect model (NONMEM) method enabled assessment of the effects of hemodynamics on the diuretic effects and also quantification of intrinsic diuretic activities, but the standard two-stage (STS) and naive pooled data (NPD) methods did not give accurate estimates. Both the STS and the NONMEM methods performed well for unbiased data arising from a one-compartment model with saturable (Michaelis-Menten) elimination, whereas the NPD method resulted in inaccurate estimates. The findings suggest that nonlinearity and/or bias problems result in poor estimation by NPD and STS analyses and that the NONMEM method is useful for analyzing such nonlinear and distorted pharmacodynamic data.

Alternative splicing of bovine terminal deoxynucleotidyl transferase cDNA

Two cDNA fragments of terminal deoxynucleotidyl transferase, which contained new insertion sequences, were found from bovine thymus cDNA. One of the clones encoded 18 new amino acids and the other encoded 9 new amino acids. In the results of genomic structure analysis around the new insertion sequences, alternative splicing of the bovine terminal deoxynucleotidyl transferase gene was suggested.