Expression of goat alpha-lactalbumin in Escherichia coli and its refolding to biologically active protein

A cDNA encoding the mature region of goat alpha-lactalbumin and the 3'-non-coding region was fused to cDNA of the N-terminal half of porcine adenylate kinase which had been placed under the control of the tac promoter in an expression vector in Escherichia coli. In addition, a methionine codon was inserted between the two cDNAs. When the plasmid carried the full-length 3'-non-coding region, little accumulation of the fused protein was observed. However, the deletion of two-thirds of the 3'-non-coding region produced significant expression of the fused protein in E. coli strain JM105. Since goat alpha-lactalbumin contains no methionine residue, the mature goat alpha-lactalbumin was isolated by CNBr digestion of the fused insoluble protein and refolded using thioredoxin. The homogeneous and biologically active goat alpha-lactalbumin was purified by Ca2+ ion-dependent hydrophobic chromatography.

Cloning and characterization of a cDNA encoding a rice 13 kDa prolamin

A cDNA library constructed from mRNAs obtained from developing rice endosperm was screened with a cDNA clone (lambda RM7) of highest frequency of occurrence (1.8%). The translation product directed by the mRNA which was hybrid-released from lambda RM7 cDNA in a wheat germ cell-free system showed a molecular size of 13 kDa when coexisting with the protein body fraction of developing maize endosperm. A polypeptide sequence composed of 156 amino acids was deduced from the nucleotide sequence. By comparison with the 19 N-terminal amino acids obtained from Edman degradation of the isolated rice 13 kDa prolamin fraction, the signal sequence was determined as consisting of 19 amino acids. The deduced polypeptide is rich in hydrophobic amino acids such as Leu and Val, and also in Gln, but lacks Lys. Hence, the amino acid composition is consistent with that of rice 13 kDa prolamin. By homology with previously reported cereal prolamins, only a single octapeptide sequence, Gln-Gln-Gln-Cys-Cys-Gln-Gln-Leu, which was observed in 15 kDa and 27 kDa zein, B- and gamma-hordein, alpha/beta- and gamma-gliadin, and gamma-secalin was conserved in the rice 10 kDa and 13 kDa prolamin. No repetitive sequences and/or sequences homologous to other cereal prolamins, except the above octapeptide, were observed for the mature 13 kDa prolamin polypeptide. The signal sequence region of the 13 kDa prolamin, however, shows homology of more than 65% in both the nucleotide sequence and the amino acid sequence with rice 10 kDa prolamin and maize zein.

Tumor accumulation mechanism of 99mTc-DL-homocysteine, a model compound for the development of tumor-imaging radiopharmaceuticals

To elucidate the tumor accumulation mechanism of 99mTc-DL-homocysteine (99mTc-Hcy), the role of mercaptalbumin, a carrier protein of 99mTc-Hcy in blood, was studied. 99mTc-Hcy bound to serum mercaptalbumin was carried to tumor tissue, efficiently adsorbed onto the cell surface, released from albumin, and taken up by the cells. An enlarged capillary permeability observed in tumor tissue played an important role in the transport process.

Comparison of alpha-helix stability in peptides having a negatively or positively charged residue block attached either to the N- or C-terminus of an alpha-helix: the electrostatic contribution and anisotropic stability of the alpha-helix

An estimation of the thermodynamic effects of a charged random coil, which is attached either to the N- or C-terminus of polyalanine, upon alpha-helix stability is attempted. A temperature-induced helix-coil transition of Ala20Lys20Phe and Lys20Ala20Phe was studied under various conditions of salt concentration and pH. By combining the results with previous ones for Ala20Glu20Phe and Glu20Ala20Phe, which have opposite electric charges to the present system [S. Ihara et al. (1982) Biopolymers 21, 131-145], the free energy of the coil to helix transition of the polyalanine block could be separated into two terms--one term for the electrostatic interaction of electric charges in the random-coil block with the alpha-helix dipole, and a second term for the intrinsic stability of the helix. The first term indicates the significance of the helix dipole-charge interactions, which affects the helix stability depending on the attaching side of the charged block and on the sign of the charges. This clearly shows the anisotropic stability of the alpha-helix. Furthermore, analysis of the dependence of these thermodynamic quantities on salt concentrations showed, assuming that the effect of the attached electric charges was symmetric (in other words, the absolute values of the electrostatic interaction terms were independent of the sign of electric charges), that the intrinsic stability of the alpha-helix was dependent on which side of the helix was attached to the random coil: a random coil attached to the N-terminus of the alpha-helix had little effect while that attached to a C-terminal significantly destabilized the helix.

cDNA cloning of an mRNA encoding a sulfur-rich 10 kDa prolamin polypeptide in rice seeds

Using a rice maturing seed pUC9 expression library, we isolated a cDNA clone corresponding to 10 kDa sulfurrich prolamin by immunoscreening. A longer cDNA clone was obtained from a λgtll library by plaque hybridization using this (32)P-labeled cDNA as a probe. A polypeptide sequence composed of 134 amino acids was deduced from the nucleotide sequence. A 24 amino acid signal peptide was assigned by computer calculation for the membrane spanning region and Edman sequencing of the purified mature polypeptide. Remarkably, 20% of methionine and 10% of cysteine were found in the mature polypeptide as well as high contents of glutamine, and hydrophobic amino acids. Part of the amino acid sequence was homologous with a conserved cysteine-rich region found in other plant prolamins. Two repeats of amino acid sequence were found in the polypeptide.

[Application of a nonisotopic southern hybridization method for sex determination from bloodstains found in criminal spots]

Bloodstains collected from criminal spots were submitted to the nonisotopic Southern hybridization (NISH) method for sex identification (Kobayashi et al., J. Forens. Sci., 33, 613-620, 1988). A RNA probe, transcripted from a Y-chromosome specific DNA sequence (Nakahori et al., Nucl. Aci. Res., 14, 7569-7580), was used for this series of investigations. Among the 95 bloodstain specimens studied, in which the sex of each was previously known, 54 (88.5%) of 61 male stains were appropriately determined to be male by the NISH method, and 28 (82.4%) of 34 female bloodstain specimens were estimated to be female. The sex of the 13 remaining stain specimens were unable to be determined by this method, but no specimen was erroneously misidentified. With regard to 12 specimens, in which the sex of each was unknown at the time of the NISH test, 5 were determined as being male and 3 were estimated as being female, though the sex of the remaining 4 specimens could not be determined. The causes in the stains that made determination impossible were analyzed using patterns of ethidium bromide fluorescence of electrophoresed gel and/or NISH, and it was concluded that this could be due to an insufficient quantity of extracted DNA (12 cases), the resistance against a restriction enzyme (EcoRI) (3 cases), and the depolymerization of the Y-chromosome specific fragment (2 cases).

Intensification of tumor affinity of 99mTc-DL-homocysteine by cooperative use of SH-containing compounds

The enhancement of tumor-specific distribution was investigated on 99mTc-DL-homocysteine (99mTc-Hcy), a possible tumor-imaging agent. In vitro HPLC analysis showed that 99mTc-Hcy did not bind to nonmercaptalbumin but to mercaptalbumin in blood. When glutathione, homocysteine or cysteine, which converts albumin from the mercapto- to nonmercapto-form, was intravenously injected into 99mTc-Hcy predosed mice bearing Ehrlich solid tumor, the SH-containing compounds did not affect the radioactivity distribution in tumor, but decreased that in blood to less than half that of untreated animals. In vitro gel filtration analysis showed that glutathione released 99mTc-Hcy from albumin. Free 99mTc-Hcy produced in blood by the treatment was rapidly excreted into urine. These results suggest that the combination of 99mTc-Hcy and SH-containing compounds is useful for tumor-imaging.

Epidermal plasminogen activator inhibitor (PAI) is immunologically identical to placental-type PAI-2

Plasminogen activator inhibitor (PAI) purified from human epidermis [(1986) FEBS Lett. 408, 273-277] was immunologically identified as placental-type PAI-2. In both fibrinolytic and synthetic substrate assays inhibitory activity of epidermal PAI was neutralized by anti-PAI-2, but not by anti-endothelial type PAI-1. Immunoblotting technique confirmed that the purified epidermal PAI is reactive with anti-PAI-2, but not with anti-PAI-1. Consequently PAI in human epidermis was demonstrable by immunohistochemical technique.

Partial purification of plasma and tissue kallikreins in psoriatic epidermis

Human psoriatic scale extracts produced kinins from heated plasma (11.3 +/- 5.5 ng kinin/mg protein) and from purified low molecular weight (LMW) bovine kininogen (4.4 +/- 1.7 ng/mg). Sephacryl S-200 gel filtration of the extracts showed three peaks of kininogenase activity with Mr values of 90,000 (K-I), 65,000 (K-II), and 35,000 (K-III). Upon DEAE-Sepharose chromatography of the Sephacryl peaks, K-I activity was found in the nonadsorbed fraction and formed kinins only from heated plasma. Peak K-II activity was resolved into two peaks, K-IIa (in the nonadsorbed fraction), which formed kinins only from heated plasma, and K-IIb (in the adsorbed fraction), which formed kinins from both heated plasma and LMW bovine kininogen. K-III kininogenase activity appeared at the same position as K-IIb and also formed kinins from both substrates. Kininogenases K-I and K-IIa had the same Km value (0.3 mM) with Pro-Phe-Arg-p-nitroanilide(pNA), similar to that found with human plasma kallikrein. The Km value of K-IIb with Val-Leu-Arg-pNA (0.8 mM) was like that found for human salivary kallikrein, whereas K-III had a low affinity for this substrate. Like plasma kallikrein, K-I and K-IIa were inhibited by soybean trypsin inhibitor, but only weakly by aprotinin. In addition the kininogenase activity of both K-I and K-IIa was neutralized by adding antihuman prekallikrein immunoglobulin G (IgG). In contrast, K-IIb and K-III were strongly inhibited by aprotinin but not by soybean trypsin inhibitor, consistent with their being tissue kallikreins. It was confirmed that K-IIb and K-III shares antigenic determinant of urinary kallikrein.

Partial purification and characterization of cysteine proteinases in eccrine sweat

Attempts were made to purify and characterize cysteine proteinases in human eccrine sweat and further clarify their origin. Benzoyl-DL-arginine-beta-naphthylamide (BANA) and L-leucine beta-naphthylamide (LeuNA) hydrolases in thermally induced sweat were sequentially purified by Sephacryl S-200 chromatography and chromatofocusing, which yielded two major peaks of BANA hydrolase activity, BANA-I and BANA-II. Both enzymes are cysteine proteinases as evidenced by stimulation of enzymic activity by dithiothreitol and ethylenediaminetetraacetic acid and its inhibition by iodoacetic acid, (PCMB), and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)-butane (E-64). Unlike BANA-II, BANA-I showed an additional aminopeptidase activity, an affinity to concanavalin A-Sepharose but no affinity to organomercurial sepharose and failed to hydrolyze benzyloxycarbonyl-phenylalanyl-arginine 4-methyl 7-coumarylamide (Z-Phe-Arg-NMec), a specific substrate for cathepsin B, which is poorly sensitive to leupeptin [inhibitor constant (Ki) = 1 X 10(-5) M] and relatively heat resistant. These and other characteristics such as its isoelectric points (PI) (= 5.8) and the Km for Arg-NMec (0.1 mM) and BANA (0.71 mM) all support the possibility that BANA-I is closely related to cathepsin H. In contrast, BANA-II is sensitive to Zn2+, leupeptin (Ki = 5.5 X 10(-9) M), is not adsorbed by concanavalin A- (Con-A)Sepharose, but is bound to organomercurial sepharose. It has a specificity to Z-Phe-Arg-NMec but not to Arg-NMec, has the molecular weight of 27, PI of 5.2, the pH optima for BANA (6.0), and the Km for BANA of 3.3 mM and the Km for Z-Phe-Arg-NMec of 0.1 mM. These features resemble those of liver cathepsin B. Leupeptin-sensitive BANA hydrolase was observed in the glandular extract of isolated sweat glands, which was increased after stimulation with methacholine and isoproterenol in vitro. The data are consistent with the notion that cathepsins B- and H-like enzymes are present in eccrine sweat and the former may be derived from the sweat gland.

Purification of epidermal plasminogen activator inhibitor

A plasminogen activator inhibitor was purified from human cornified cell extract by DEAE-Sepharose, Sephacryl S-200, and high-performance liquid chromatographies on hydroxyapatite HPHT and anion-exchanger Mono Q at pH 7.2 and 8.0. The purified inhibitor showed Mr 43,000 and pI 5.2 50% inhibition of fibrinolytic activity (1.5 IU) of urokinase and tissue-type plasminogen activator was attained by 0.60 ng and 11.0 ng purified inhibitor, respectively. Synthetic substrate assay demonstrated slow tight-binding inhibition to both urokinase and tissue-type plasminogen activator. The inhibitor did not inactivate plasmin, thrombin, glandular kallikrein or trypsin.

Elastase activity in granulomatous inflammation in experimental murine leprosy

Proteolytic activity for [3H]elastin, pyro-Glu-Pro-Val-pNA(S-2484), and Suc-(Ala)3-pNA(AAApNA) was demonstrated in the bound fraction extracted with 2 M KSCN + 0.1% Triton X-100 from hypersensitivity-type murine lepromas in C57BL/6N mice, while elastase-inhibitor activity was separately observed in the soluble fraction extracted with a Tris-saline buffer. Sephacryl S-200 gel chromatography showed a peak of elastolytic activity with approximately 20,000 in molecular weight. The following DEAE-Sepharose chromatography demonstrated three fractions of elastolytic activity (E-I, II, III). The inhibitory profile showed that E-I is a thiol proteinase, while E-II and E-III belong to serine proteinase-type elastases. Both E-II and E-III showed different properties with neutrophil elastase or elastase secreted from cultured macrophages, but identical characteristics to membrane bound-type elastase of monocytes. A lower level of elastolytic activity was detected in the bound fraction of nonhypersensitivity-type murine lepromas in CBA/N mice, suggesting a more involvement of membrane bound-type elastase from monocytes/macrophages during the tissue remodelings of hypersensitivity-type granulomas.

A new mouse model of genetically transmitted polycystic kidney disease

The clinical and pathologic characteristics of the murine polycystic kidney were examined in a mutant cy/cy mouse found in the KK strain, which is known to be a diabetic strain. This cy/cy mutant appeared to resemble human adult polycystic kidney disease in clinical course and morphology although inheritance was an autosomal recessive trait. Histologic studies of early postnatal animals suggested that cystic alterations might occur in any part of a collecting tubule or nephron. The cy/cy mutant might be a useful model animal for further investigation of early morphologic alterations and progression of cystic disease.

Morphologic changes in the urinary bladder and stomach after long-term administration of sodium saccharin in F344 rats

The effects of long-term administration of sodium saccharin on the urinary bladder and stomach of F344 rats were investigated. Sixty-eight male F344 rats, aged 7 weeks at the beginning of the experiment, were maintained on diet supplemented with 5% sodium saccharin for 112 weeks. Animals were killed periodically and investigated for gross and microscopic lesions in the urinary bladder and stomach. Papillary or nodular hyperplasia was evident in the urinary bladder epithelium from 8 weeks onwards although no papillomas or transitional cell carcinomas developed. Lesions observed in the bladders of control animals fed the basal diet without the saccharin supplement were limited throughout the experiment to a few areas of simple hyperplasia. While no changes were apparent in the stomach of control animals, a 100% incidence of hyperkeratosis at the limiting ridge of the forestomach was observed after 80 weeks administration of saccharin, 5 of 20 animals also having papillomas. Furthermore, erosion was pronounced in the glandular stomach of saccharin-treated animals with 4 cases of atypical gland being observed. No histopathological lesions were apparent in the liver, kidneys or spleen of either control or experimental groups.

Appearance of dark keratinocytes following intracutaneous injection of cholera toxin in mouse skin

Intracutaneous injection of cholera toxin (CT), exotoxin of Vibrio cholerae, induces epidermal hyperplasia in mice, rats, and hamsters. In the work reported here we found that, like other hyperplasiogenic compounds such as 12-O-tetradecanoylphorbol-13-acetate which are tumor promoters, CT induces dark basal keratinocytes (dark cells) in the epidermis of mice. These are distinct from other epidermal cells since they contain dense cytoplasm rich in ribosomes and tonofilaments. This was demonstrated by electron microscopy and by toluidine blue staining of paraffin- or Epon-embedded sections. They comprised 3.1% of interfollicular basal cells 24-64 h after injection of 1 ng CT as compared with 0.5% in saline-injected skin. It was found by autoradiography of paraffin sections that about 47.2% of dark cells were labeled with [3H]thymidine at these times, while under the same conditions, labeling indices of basal cells were about 30% at the peaks. These results are discussed in relation to tumor promotion in two-stage carcinogenesis of mouse skin.

Purification and characterization of keratin hydrolase in psoriatic epidermis: application of keratin-agarose plate and keratin-polyacrylamide enzymography methods

Keratin-agarose plate and keratin-polyacrylamide enzymography methods were developed to demonstrate proteolytic digestion of epidermal keratin. By applying these methods, keratin hydrolase was purified from Tris-buffered saline extract of psoriatic scales by 50% ammonium sulfate precipitation, passage through a lysine-Sepharose column, DEAE-Sepharose, Sephacryl S-200, high-performance cation-exchange chromatography on Mono S, and aprotinin-Sepharose affinity chromatography. The final preparation demonstrated a single protein band at molecular weight 30,000 judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Furthermore, in keratin-polyacrylamide slab gels, the purified enzyme preparation showed a translucent band at molecular weight 30,000, indicating keratin digestion. Keratin hydrolase digested reassembled epidermal keratin as well, whereas it had no effect on guinea pig hair keratin. The enzyme demonstrated a high level of hydrolytic activity on Ile-Pro-Arg-p-nitroanilide and other peptidyl arginine substrates, while it showed a low level of activity on Val-Leu-Lys-p-nitroanilide, and no activity on Arg-Pro-Tyr-p-nitroanilide, Glu-Pro-Val-p-nitroanilide, or Ala-Ala-Ala-p-nitroanilide. The keratin hydrolase was a serine proteinase, inactivated by diisopropylfluorophosphate, phenylmethylsulfonyl fluoride, tosyl-lysyl-chloromethyl ketone, antipain, leupeptin, soybean trypsin inhibitor, aprotinin, and p-aminobenzamidine. The keratinolytic activity was not detected in normal epidermal extract.

Plasminogen activator and plasminogen activator inhibitor associated with granulomatous inflammation: a study with murine leprosy

Plasminogen activator that is associated with the development of hypersensitivity granulomas (gPA) was partially purified from a saline soluble fraction of murine lepromas elicited in "resistant" mice, C57BL/6N. The gPA was shown to consist of two subspecies (23,000 and 48,000 in molecular weight) with essentially identical enzymologic properties. The gPA was found to be a relatively heat stable weakly alkaline serine proteinase with trypsin-like characteristics in the specificity for synthetic substrates and proteinase inhibitors. It showed a high affinity for H-D-Ile-Pro-Arg-pNA (Km = 1.4 X 10(-4) M) H-D-Val-Leu-Lys-pNA (Km = 5.2 X 10(-4) M), and L-pyroGlu-Gly-Arg-pNA (Km = 9.3 X 10(-4) M). The gPA did not demonstrate antigenic cross reaction with urokinase-type or tissue-type plasminogen activator. Two distinct enzymatic regulators of the gPA were also demonstrated in the saline soluble fraction of the hypersensitivity granulomas. The gPA and its regulation are assumed to be correlated with macrophage activation in the hypersensitivity granulomas.

Differences in susceptibility to sodium saccharin among various strains of rats and other animal species

Differences in the susceptibilities to sodium saccharin of the urinary bladder epithelium in various strains of rats and other animal species were examined. In Experiment 1, male ACI, Wistar, F344 and Sprague-Dawley rats were administered 5.0% sodium saccharin in the diet for 52 weeks. Rats were killed after weeks 12, 24, 36 and 52. In ACI rats, sodium saccharin induced not only preneoplastic lesions of the urinary bladder, but also tumors. However, in other strains it did not. The urinary bladder of ACI rats given sodium saccharin had the most marked lesions under scanning electron microscopy, with less marked changes in Wistar and F344 rats. Sprague-Dawley rats were resistant to sodium saccharin. In Experiment 2, male F344 rats, B6C3F1 mice, Syrian golden hamsters, and Hartley guinea pigs were given 5.0% sodium saccharin in the diet for 20 weeks. The animals were sacrificed sequentially. Rats developed urinary bladder lesions during the experiment, as detected by light microscopy and scanning electron microscopy. Increased DNA synthesis of the urinary bladder epithelium was detected in rats by autoradiography. However, mice, hamsters and guinea pigs were resistant to sodium saccharin. These results indicate that there are strain and species differences in the urinary bladder response to sodium saccharin.

Comparative study with two polar types of murine leprosy: an involvement of plasminogen activator and its possible regulating factor in the granulomatous tissue reaction

Enzymatic activities in a saline-extractable fraction from two polar types of murine lepromas were investigated using pyroglutamyl-glycyl-arginine-p-nitroanilide and plasminogen-rich, as well as plasminogen-free, fibrin plates. An inhibitor activity for urokinase was also measured. C57BL/6NJcl (immunologically high responder strain) mice inoculated with 2 X 10(8) Mycobacterium lepraemurium developed a localized lepromatous lesion after 4 weeks. The tissue extracts obtained after 4-6 weeks exhibited inhibition for urokinase (8.8 IU/mg protein), but no enzymatic activity. After 8-11 weeks, when the lepromas showed an ulcerative change, prominent peptide hydrolytic activity (84.8 nmol/mg/protein/ min) was demonstrated. The fibrin plate assay confirmed that plasminogen activator is predominantly involved (26.4 IU/mg protein). The proteolytic activation was apparently correlated with discharge of purulent materials containing the bacilli and subsequent limitation of leproma development. However, similar modulation of the fibrinolytic enzyme-inhibitor system was not shown in CBA/N mice (immunologically low responders). The tissue extracts showed a low level of urokinase inhibitor activity (1.9 IU/mg protein), but no peptidolytic or plasminogen activator activity. Consequently, lepromas were developed progressively until 25 weeks after infection and dissemination from the lepromatous lesion took place thereafter. In comparison with histologic findings, which revealed accumulation of lymphocytes and mononuclear cells in the peripheral zone of lepromatous lesions in the C57BL/ 6NJcl, but not in the CBA/N mice, a controlling mechanism of plasminogen activator in tissue is assumed to be involved in the development of the granulomatous tissue reaction.

Tumorigenicity of citrinin in male F344 rats

This study reports on the tumorigenicity of citrinin, a nephrotoxic mycotoxin. Male F344 rats were fed 0.1% citrinin in the diet for up to 80 weeks. The first renal tumor was seen grossly in a rat receiving citrinin which was killed at week 52. Histopathology of the kidneys showed renal adenomas in 35 of 48 (72.9%) rats that survived after 40 weeks. No renal tumors were seen in the control rats.

Cellular localization of thiol-proteinase inhibitor in the epidermis of the newborn rat

Subcellular distribution of a thiol-proteinase inhibitor protein was determined in the epidermis of the newborn rat by light and electron microscopy. This protein was highly soluble in basal cells and concentrated on ribosomes in the perinuclear region. Solubility in Tris buffer decreased in granular and cornified cells in which the protein appeared on polysomes which were attached on other cellular structures such as dense homogenous deposits and tonofilaments. The protein also appeared to be deposited on the plasma membrane and became insoluble in Tris buffer at 37 degrees C, but solubilized in 1 M phosphate buffer. Location of the protein around keratohyalin granules or by the plasma membrane suggested that the inhibitor protein bound to cysteine-rich protein of the epidermis with or without forming a thiol-proteinase inhibitor complex. The thiol-proteinase inhibitor protein seems to contribute to epidermal cell differentiation at multiple points through changes in its solubility and subcellular localization from basal cells to cornified cells.

Chemical characterization, synthesis and distribution of proteinase inhibitor in newborn rat epidermis

A protein solubilized in Tris-HCl/saline buffer from keratinized cells of newborn rat epidermis exhibited inhibitor activity to papain and ficin, but not to trypsin, cathepsin D and pepsin. This protein was purified from keratinized cells as well as nonkeratinized and germinative cells by means of IgG affinity chromatography. The inhibitors extracted from all cell layers were immunologically identical and had a molecular weight of approximately 12,500 +/- 500. Since amino acid analysis showed that the inhibitor contains about 35 residues of glycine per mol, [3H]glycine was used to investigate synthesis of the protein. The inhibitor from nonkeratinized and germinative cells was radioactively labeled by 2 h after injection and appeared in keratinized cells by 48 h after injection. Indirect immunofluorescence microscopy demonstrated in situ distribution of the protein in the entire epidermis, and the protein localized by the plasma membrane in granular cells and diffusely in keratinized cells was shown to be insoluble in Tris-HCl saline buffer. The results indicate that a thiol-proteinase inhibitor is synthesized in epidermal cells during keratinization and is retained as part of the cytoplasmic structure

Synthesis and beta-adrenergic blocking action of a new thiazolylthiopropanolamine derivative

The synthesis of (+/-)-2-(3'-tert-butylamino-2'-hydroxypropylthio)-4-(5'-carbamoyl-2'-thienyl)thiazole hydrochloride is described. The new compound antagonized the cardiovascular effects, such as positive chronotropic, positive inotropic, or depressor arterial blood pressure responses, elicited by intravenous isoproterenol; it was 9--14 times as potent as propranolol in anesthetized open chest dogs. The oral administration of the compound reduced isoproterenol tachycardia in conscious dogs. It was about five times as potent as propranolol in this test, with maximal action after 1 hr, and its duration was significantly longer than that of propranolol.

Total synthesis of indole and dihydroindole alkaloids. XII. Selective functionalization of various bisindoles. Efficient syntheses of leurosine and related bisindole alkaloid derivatives

Studies involving selective functionalization of the indole unit in a number of bisindole alkaloids and related synthetic derivatives are described. These investigations include such reagents as tert-butyl hydroperoxide, which provides an efficient procedure for epoxidation of olefinic linkages, mercuric acetate, osmium tetroxide, and iodine under basic conditions and oxygenation under acidic conditions. Efficient syntheses of leurosine (8) and various novel vinblastine derivatives are developed.

Effect of iodoacetamide or Tween 60 on methylnitrosocyanamide carcinogenesis in rat glandular and forestomach

The effect of iodoacetamide or Tween 60 on carcinogenicity of methylnitrosocyanamide (MNC) in rats was examined. A significant increase in the incidence of the forestomach tumors (P less than 0.01) was observed in rats treated with MNC and iodoacetamide simultaneously. Moreover, there were 2 cases of glandular stomach tumors in rats treated with MNC and Tween 60 simultaneously. They were one well-differentiated adenocarcinoma and one polypoid hyperplasia. This result indicates that MNC under certain conditions is carcinogenic to the glandular stomach of rats in addition to the forestomach. Tween 60 might act by facilitating direct contact between MNC and the glandular stomach mucosa.