Development of multiple AI pipelines that predict neoadjuvant chemotherapy response of breast cancer using H&E-stained tissues

In recent years, the treatment of breast cancer has advanced dramatically and neoadjuvant chemotherapy (NAC) has become a common treatment method, especially for locally advanced breast cancer. However, other than the subtype of breast cancer, no clear factor indicating sensitivity to NAC has been identified. In this study, we attempted to use artificial intelligence (AI) to predict the effect of preoperative chemotherapy from hematoxylin and eosin images of pathological tissue obtained from needle biopsies prior to chemotherapy. Application of AI to pathological images typically uses a single machine-learning model such as support vector machines (SVMs) or deep convolutional neural networks (CNNs). However, cancer tissues are extremely diverse and learning with a realistic number of cases limits the prediction accuracy of a single model. In this study, we propose a novel pipeline system that uses three independent models each focusing on different characteristics of cancer atypia. Our system uses a CNN model to learn structural atypia from image patches and SVM and random forest models to learn nuclear atypia from fine-grained nuclear features extracted by image analysis methods. It was able to predict the NAC response with 95.15% accuracy on a test set of 103 unseen cases. We believe that this AI pipeline system will contribute to the adoption of personalized medicine in NAC therapy for breast cancer.

Printable PICN Composite Mechanically Compatible with Human Teeth

Polymer-infiltrated ceramic network (PICN) composites are mechanically compatible with human enamel, and are therefore promising dental restorative materials. Fabrication technology for PICN composites used in tooth restorative material has been established through computer-aided design/computer-aided manufacturing (CAD/CAM) milling, however, to date, has not been successfully developed using 3-dimensional (3D) printing. This study aimed to develop a 3D-printable PICN composite as a restorative material. The PICN composite was fabricated using a specific method based on 3D printing. A 3D-printable precursor slurry containing a high concentration of silica nanoparticles was produced and 3D-printed using stereolithography (SLA). The 3D-printed object was sintered to obtain a nano-porous object, and subsequently infiltrated and polymerized with resin monomer. Three different fabrication condition combinations were used to produce the 3D-printed PICN composites, which were characterized based on microstructure, mechanical properties, inorganic content, physicochemical properties, and overall shrinkage. The 3D-printed PICN composites were also compared to 2 commercially available CAD/CAM composite blocks, namely a PICN composite and a dispersed-filler composite. The 3D-printed PICN composites exhibited a nano-sized dual-network structure comprising a silica skeleton with infiltrated resin. The 3D-printed PICN composite exhibited a similar Vickers hardness to enamel, and a similar elastic modulus to dentin. The 3D-printed PICN composite exhibited comparable flexural strength (>100 MPa) to the CAD/CAM block, and acceptable water sorption and solubility for practical use. Further, the 3D-printed model-crown underwent isotropic shrinkage during sintering without fatal deformation. Overall, the potential of this 3D-printable PICN composite as a restorative material with similar mechanical properties to human teeth was successfully demonstrated.

Usefulness of peripheral-pressure-directed balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

Background

Balloon pulmonary angioplasty (BPA) in expert center may be considered in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are technically non-operable for pulmonary endarterectomy. BPA based on objective quantitative methods has not been established. The endpoint at BPA sessions has not been clarified yet.

Objectives

The purpose of this study was to investigate the usefulness of BPA according to peripheral pressure measured by pressure wire or catheter.

Methods

This study included consecutive 143 CTEPH who underwent cardiopulmonary exercise test with right heart catheterization after BPA. All patients were divided into 2 groups such as angio-guided (n=47) group or pressure-guidedgroup (n=96). In pressure-guided group, the pulmonary arterial pressure (PAP) proximal and distal to the target lesion and the ratio of the 2 pressures were measured by the pressure wire or catheter. the endpoint was determined to when the pressure ratio of distal to proximal pressures was >0.7 to 0.8 finally. The dilation was stopped when the distal mean PAP after each dilation reached 35 mm Hg and when the baseline mean PAP was >35 mm Hg. Changes of hemodynamic parameters such as PAP and pulmonary vascular resistance (PVR) from baseline, and mean PAP and PVR at peak oxygen consumption, and pulmonary arterial pressure – cardiac output (PA-CO) slope were compared between two groups. All data except changes of hemodynamics from baseline were expressed by median [25th percentile-75th percentile]. Changes of hemodynamics from baseline were expressed by average [95% confidence interval]

Results

The median age and male were 66 [56–72] years old and 35. There were no significant differences in number of sessions and dilated vessels between two groups (Angio-guided group vs. Pressure-guided group: 4 [3–6] vs. 4 [3–5], P>0.05; 19 [12–22] vs. 17 [13–22], P>0.05). Changes of PAP and PVR from baseline in pressure-guided group was significantly higher than in angio-guided groups (Angio-guided group vs. Pressure-guided group; ΔPAP: −19 [−20 to −17] vs. −20 [−21 to −20], P>0.05; ΔPVR: −6.0 [−6.3 to −5.7] vs. −6.6 [−6.8 to −6.3], P<0.01). Mean PAP and PVR at peak oxygen consumption (VO2) and PA-CO slope in pressure-guided group were significantly lower than in angio-guided group (Angio-guided group vs. Pressure-guided group; PAP at VO2: 43 [36–50] vs. 39 [34–43], P<0.05; PVR at VO2: 2.7 [1.9–4.5] vs. 2.2 [1.6–2.9], P<0.01; PA-CO slope: 3.8 [2.1–5.2] vs. 2.9 [1.9–4.0], P<0.05).

Conclusions

Peripheral-pressure-directed BPA can improve hemodynamics at rest and exercise more effectively.

Funding Acknowledgement

Type of funding source: None

REDUCTION IN AMBIENT GAMMA DOSE RATE FROM RADIOCESIUM DUE TO SNOW COVER

In the present study, variations in ambient gamma dose rate associated with snow cover were examined in a radioactive-contaminated site in Fukushima Prefecture, Japan. The ambient gamma dose rates decreased with increasing snow depth. The reduction trends were different between fresh snow (0.1-0.2 g/cm3) and granular snow (0.3-0.4 g/cm3) depending on snow density. Snow cover water content (snow water equivalent) calculated from snow depth and density was a key parameter governing the reduction in the ambient gamma dose rate. The ambient gamma dose rates reduced to 0.6 and 0.5 at 4 g/cm2 and 8 g/cm2 of snow water equivalent, respectively. Based on gamma-ray flux density distributions, the ambient gamma dose rates from the primary gamma rays decreased more compared to those from scattered gamma rays due to snow cover.

Variation in Activities of Non-Plasmin Fibrinolytic Proteinase and Plasminogen-Activator in the Lung and Spleen Induced by Bacterial Endotoxin in Rats with Special Reference to the Effects of MD-805

The behavior of direct fibrinolytic (non-plasmin) proteinase activity and plasminogen-activator activity in the lung and spleen was investigated in rats after a single intravenous injection of bacterial endotoxin, and the influence of thrombin inhibitors on the effects of the endotoxin was assessed.

The non-plasmin fibrinolytic activitiy was markedly increased following a decrease of plasminogen-activator in the lung. In addition, variations in hematological parameters, i.e. a decrease of platelet count, fibrinogen level and antithrombin III, and an increase of blood urea nitrogen and euglobulin fibrinolytic activity, were induced by the injection, indicating the occurrence of disseminated intravascular coagulation.

In comparative studies on the effects of the endotoxin injection and thrombin infusion, in the lung and spleen an increase of fibrinolytic proteinase activity was induced in a similar manner; the plasminogen-activator activity in the lung was decreased by the endotoxin injection but not decreased by the thrombin infusion.

In prevention studies with heparin and MD-805, the latter was found to prevent the decrease of either fibrinogen or platelet count. However, the former failed to prevent the decrease of platelet count although that of the fibrinogen level was prevented. Heparin and MD-805 exerted no preventive effect on the endotoxin-induced variations of proteinase activity and plasminogen-activator activity in the lung.

Human Leukocyte Elastase-Like Proteinase Purified by Affinity Chromatography with Suc-L-Tyr-D-Leu-D-Val-pNA, and Its Identification with Human Spleen Fibrinolytic Proteinase

Elastase-like proteinase (ELP) extracted with 2 M NaClO4 from human leukocytes was purified by a new affinity chromatography technique with Suc-L-Tyr-D-Leu-D-Val-pNA, following delipidation, salting out and Sephadex gel chromatography. The purified preparation contained practically no chymotrypsin-like proteinase activity, and it was homogeneous on SDS polyacrylamide gel electrophoresis. The enzyme so purified readily degraded fibrin, fibrinogen, elastin and -Val type synthetic peptide substrates, such as Suc-L-Ala-L-Tyr-L-Leu-L-Val-pNA and Suc-L-Tyr-L-Leu-L-Val-pNA. A special increase in ELP activity by adding chaotropic ions was observed. The enzymatic properties of the ELP were very similar to those of spleen fibrinolytic proteinase (SFP). ELP and SFP were identified immunologically using mice antisera against purified ELP.

Analysis of structural components and molecular construction of soybean soluble polysaccharides by stepwise enzymatic degradation

Soybean soluble polysaccharides (SSPS) extracted from soybean cotyledons have a pectin-like structure. The core polysaccharides after treatments with four kinds of hemicellulases and a pectinase contained approximately equal numbers of L-rhamnose and D-galacturonate residues, suggesting the presence of the rhamnogalacturonan (RG) I structure consisting of the diglycosyl repeating unit, -4)-alpha-D-GalpA-(1-->2)-alpha-L-Rhap-(1-. The lengths of RG chains were calculated as approximately 15, 28, and 100 diglycosyl repeats. The RG components linked to each other by intervention of galacturonan (GN) chains, constituting the backbone of SSPS. All arabinose residues, which constitute 21% of total SSPS sugars, were found to be in side chains from RG regions, and this was also true for galactose residues, which constitute 50% of total sugars. Of arabinose residues, 94% are present as alpha-1,3- or alpha-1,5-arabinans, and 89% of galactose residues were present as beta-1,4-galactans. Galactan chains are modified with arabinose, xylose, fucose, and glucose at the sites close to the RG regions.

Application of electrolyzed acid water to sterilization of denture base part 1. Examination of sterilization effects on resin plate

Bactericidal activities of electrolyzed strong and weak acid waters for acrylic denture base resin were evaluated in order to discuss the applicability of these waters for sterilization of denture base. Only 1-minute immersion in the electrolyzed strong or weak acid water could completely eliminate the attached bacteria, Staphylococcus aureus 209P, on the resin plate. When the resin was relined with tissue conditioner, 5-minute immersion or 1- to 2-minute ultrasonic cleaning reduced the number of the bacteria from 10(5)/cm2 level to 10(1)/cm2 and no surviving bacteria could be detected after 10-minute treatment. These findings suggest that both the electrolyzed strong and weak acid waters are well applicable to the disinfectant for acrylic denture base showing excellent bactericidal activities in a significantly shorter treatment as compared with the conventional denture cleaning.

Preoperative evaluation of cardiopulmonary reserve with the use of expired gas analysis during exercise testing in patients with squamous cell carcinoma of the thoracic esophagus

OBJECTIVE

We evaluated the usefulness of analyzing expired gas during exercise testing for the prediction of postoperative cardiopulmonary complications in patients with esophageal carcinoma.

BACKGROUND DATA

Radical esophagectomy with 3-field lymphadenectomy is performed in patients with thoracic esophageal carcinoma but has a high risk of postoperative complications. To reduce the surgical risk, we performed preoperative risk analysis using 8 factors. Although hospital mortality was decreased when this risk analysis was used, severe cardiopulmonary complications still occurred.

METHODS

The study group consisted of 91 patients who had undergone curative esophagectomy with 3-field lymphadenectomy. The maximum oxygen uptake, anaerobic threshold, vital capacity, percent vital capacity, forced expiratory volume in 1 second, percent forced expiratory volume, V.(25)/HT, forced expired flow at 75% of forced vital capacity to height ratio (FEF(75%)/HT), forced expired flow at 50% to 75% of forced vital capacity ratio (FEF(50%)/FEF(75%)), percent diffusion capacity for carbon monoxide, and arterial oxygen tension were measured. Patients were divided into 2 groups on the basis of the presence or absence of postoperative cardiopulmonary complications.

RESULTS

Only the maximum oxygen uptake was significantly different between the 2 groups. All patients were grouped according to the value of the maximum oxygen uptake, and the occurrence of postoperative cardiopulmonary complications was calculated for each group. A cardiopulmonary complication rate of 86% was found for patients with a maximum oxygen uptake of less than 699 mL. min(-1). m(-2); for those with a value of 700 to 799 mL. min(-1). m(-2), the complication rate was 44%.

CONCLUSIONS

The maximum oxygen uptake obtained by expired gas analysis during exercise testing correlates with the postoperative cardiopulmonary complication rate. On the basis of these results, esophagectomy with 3-field lymphadenectomy can be safely performed in patients with a maximum oxygen uptake of at least 800 mL. min(-1). m(-2).

Production of a new hybrid anthracycline 4-O-methylepelmycin by heterologous expression of dnrK in epelmycin-producing Streptomyces violaceus

A new hybrid anthracycline antibiotic was produced by heterologous expression of dnrK encoding carminomycin 4-O-metyltransferase in an epelmycin-producing Streptomyces violaceus. pMK100 was constructed by insertion of Steptomyces peucetius dnrK gene in Steptomyces-expression vector pIJ6021 and introduced to the epelmycin producer. The transformant produced a hybrid anthracycline antibiotic together with host epelmycins when cultured in antibiotic production medium in the presence of thiostrepton. The hybrid anthracycline was determined to be 7-O-L-rhodosaminyl-4-O-methyl-epsilon-rhodomycinone (4-O-methylepelmycin D). However, the attempts on production of hybrid 4-O-methylaclarubicin and 4-O-methyl-1-deoxyobelmycin by the transformants of aclarubicin and 1-deoxyobelmycin producers with pMK 100 were unsuccessful.

[Colorectal cancer in spouses of colorectal cancer patients]

Married couples share home environments and life style for years. In the case of colorectal cancer, an association with insulin resistance was reported. We determined the presence of the insulin-resistance syndrome (IRS, 1 or more of the following: body mass index of > 25 kg/m2, diabetes, or hyperlipidemia) in 84 colorectal cancer patients, of whom 61 patients (73%) had IRS. The incidence of the distal colorectal cancer, which has been declining in the United States, was significantly higher in the IRS group than in the non-IRS group (75.4 vs 52.2%, p = 0.0400). Some mechanisms may promote the progression of mucosal lesions to invasive cancers in the distal colorectum. There were no significant differences with respect to the age (64.6 +/- 9.4 vs 64.3 +/- 11.3 yr, p = 0.8298), height (159 +/- 9 vs 157 +/- 8 cm, p = 0.1375), and body mass index (22.2 +/- 3.6 vs 22.4 +/- 2.7 kg/m2, p = 0.6364) between the patients and their spouses. In 84 couples in whom colorectal cancer develops at least in one may then not illustrate the nursery rhyme: "Jack Sprat could eat no fat, His wife could eat no lean...". The spouses had been married for an average of 38 years, and in 30 spouses who had been followed in a colorectal cancer screening, 5 developed colorectal cancer. To diminish the incidence of colorectal cancer in Japan, we might advise screening colonoscopy to the spouses of colorectal cancer patients, or déjà vu all over again?

Effects of bacterial glyceroglycolipid M874B on growth and TPA-induced differentiation of HL60 cells

Bacterial monogalactosyldiacylglycerol M874B (MGDAG), which protects against oxygen radicals, was found to increase the growth of the human promyelocytic leukemia cell HL60 when added to the cell culture, but suppresses the 12-O-tetradecanoyl phorbol-13-acetate-induced differentiation. Analogous MGDAG, S365B had weak, but similar effects. These activities were not observed with analogous plant glyceroglycolipids and diacylglycerol.

Chemical structure of nuclear proteins which are phosphorylated during meiotic maturation of starfish oocytes

Oocytes of the starfish, Asterina pectinifera, are arrested at the G2 phase of meiosis I and possess a prominent germinal vesicle in which maternal stores of nuclear proteins which are destined for use primarily by the early embryo are stored. Germinal vesicle breakdown and subsequent oocyte maturation is triggered by activation of the p34(cdc2)/cyclin B complex, which is present as the preform in the cytoplasm. The aim of the present study was to identify and biochemically characterize in vivo substrates of the kinase. Two nucleic acid binding nuclear proteins designated NAAP1 and NAAP2 were found, both of which contain 345 amino acid residues with pI 3. 6 and which serve as substrates. The only difference between the two proteins was in the primary amino acid sequence at position 51, which is Asn in NAAP1 but Thr in NAAP2. NAAPs are phosphorylated in vivo during oocyte maturation but not at the meiotic G(2) stage. NAAPs are phosphorylated in vitro by the cdc2 kinase on the same site as in vivo. Although there are other evolutionarily conserved consensus sequences for phosphorylation by mitotically active cdc2 kinase in NAAPs and NAAP-derived fragments containing the sequences were efficiently phosphorylated in vitro, these sites in the intact NAAPs were not phosphorylated either in vivo or in vitro. These results suggest that the tertiary structure of NAAPs affects the target specificity of the cdc2 kinase.

A new type of glycoglycerolipids from Corynebacterium aquaticum

A new type of glycoglycerolipids, S361A and S365A, were obtained from Corynebacterium aquaticum strains, S361 and S365, newly isolated from soils, and were identified as (2R)-1-[alpha-glucopyranosyl-(1alpha-3)-(6O-acyl-alpha-manno pyranosyl)]-3-O-acylglycerol and (2R)-1-[alpha-mannopyranosyl-(1alpha-3)-(6-O-acyl-alpha-mannopyran osyl)]-3-O-acylglycerol, respectively. S365A was identical to a novel glycoglycerolipid recently isolated from some bacteria, but S361A was a new analog having a glucosylmannosyl in place of the dimannosyl group. Our results indicate that this sn-2 lysotype of glyceroglycolipids may be widely distributed in bacteria.

Protective effects of bacterial glyceroglycolipid M874B against cell death caused by exposure to heat and hydrogen peroxide

It was revealed by bioassay using sodA and katA mutants of Bacillus subtilis that the bacterial monogalactosyldiacylglycerol M874B, previously characterized as an alkyl peroxyl radical scavenger, was also capable of protecting cells from death caused by heating and exogenous H2O2. Chemical assays using the Fenton reaction and xanthine-xanthine oxidase revealed that M874B could quench hydroxyl radicals but not superoxide anions. Wheat monogalactosyldiacylglycerol, but neither digalactosyldiacylglycerol nor synthetic diacylglycerol, also had the same activities as those of M874B, although it was less efficient than M874B. These results suggest that monogalactosyldiacylglycerols such as M874B are a new type of oxygen radical scavengers capable of quenching some reactive oxygen species.

Ultraviolet spectrometric determination of neutral monosaccharides by HPLC with ethanolamine

The reaction between ethanolamine and sugars in a borate solution gave intense UV absorption at 310 nm. By adding ethanolamine in the mobile phase, simple and sensitive ion-exchange HPLC of sugar-borate complexes was achieved. This method can be used to measure as little as 100 pmole of seven monosaccharides from pectic polysaccharides.

Molecular characterization of a novel nucleolar protein in starfish oocytes which is phosphorylated before and during oocyte maturation

In response to 1-methyladenine, a maturation-inducing substance, starfish oocytes undergo reinitiation of meiosis with germinal vesicle breakdown through activation of p34cdc2-cyclin B, which results in the dispersal of the nucleolus. Little information has been elucidated thus far on nucleolar proteins that are phosphorylated by p34cdc2-cyclin B during meiotic maturation. Here, we describe a novel nucleolar protein of the starfish Asterina pectinifera oocyte, which is designated ANO39 and which is phosphorylated during meiotic maturation. A full-length ANO39 cDNA of 2106 base pairs encodes a polypeptide of 346 amino acids having a calculated Mr of 39 005. The amount of ANO39 is kept nearly constant during oocyte maturation and embryogenesis up to the midgastrula stage. The transcript encoding ANO39 was present in growing oocytes but not in full-grown ones, as evidenced by Northern blot hybridization. Ser145 is specifically phosphorylated when ANO39 is incubated in vitro with purified starfish p34cdc2-cyclin B. This phosphorylation site corresponds to that is phosphorylated during meiotic maturation in vivo. Immunoblot analysis using phosphoserine145-specific antibody as a probe revealed that some populations of ANO39 of the immature oocytes at the G2 stage have been already phosphorylated on Ser145 and Ser145 is maximally phosphorylated during meiotic maturation.

The cadherin-like protein is essential to specificity determination and cytotoxic action of the Bacillus thuringiensis insecticidal CryIAa toxin

The Bacillus thuringiensis CryIAa toxin binds a cadherin-like protein (BtR175) on the brush-border membranes of the Bombyx mori midgut columnar cells, which are the targets. By introducing the BtR175 gene with a baculovirus, Spodoptera frugiperda Sf9 cells expressed BtR175 protein on the cell membrane and became susceptible to the CryIAa toxin. The toxin bound the cadherin repeat adjacent to the membrane and made a pore that passed inorganic ions, causing the cell to swell and burst. This was not observed with a BtR175 variant lacking the toxin-binding site. This in vitro experiment mimicked the specific insecticidal action of the toxin in vivo well.

The differential effects of aspirin on platelets, leucocytes and vascular endothelium in an in vivo model of thrombus formation

Unanswered questions remain with regard to the therapeutic use of aspirin and the selective inhibition of thromboxane A2 and prostacyclin in platelets and endothelial cells. In the present study, the effects of aspirin on platelets and endothelial cells in vivo were examined using a helium-neon (He-Ne) laser-induced thrombosis model. Single intravenous injections of aspirin at concentrations of more than 0.5 mg/kg body weight mediated a dose dependent inhibition of thrombus formation in arterioles but not in venules. This antithrombotic effect was optimum after 15 min and declined after 90 min. Potent antithrombotic activity in arterioles was manifest at doses of 2.5 mg/kg to 50 mg/kg, and initial inhibition of thrombogenesis in vivo was most pronounced at high doses. Oral aspirin also inhibited thrombus formation in arterioles but not in venules, although the antithrombotic effects were delayed and prolonged. Maximum inhibition of ex vivo, collagen induced platelet aggregation by aspirin was observed approximately 180 min after intravenous injection. The results demonstrated that, although aspirin might have differential effects on platelets and endothelial cells, potent antithrombotic activity was manifest in arterioles at all concentrations. The findings suggest that the concept of the aspirin dilemma might be ignored for therapeutic purposes in many clinical circumstances. The antithrombotic effects of aspirin were unchanged in granulocyte-depleted animals, indicating that leucocyte-related mechanisms including neutrophil superoxide anion production did not modulate the potency of aspirin in this model.

Surgical treatment of lower rectal cancer with sphincter preservation using handsewn coloanal anastomosis

The present study was designed to evaluate the technical feasibility and oncologic results of performing handsewn coloanal anastomosis (CAA). A total of 46 patients treated for lower rectal cancer using CAA were retrospectively studied, and the oncologic results were compared with those of 105 patients treated with abdominoperineal resection (APR). CAA was performed in patients who had both good mobility of the tumor and a distal clearance margin of more than 1.0 cm. No significant difference was noted in the mortality rates following the two operations (CAA 2.2% vs APR 1.9%). Pelvic recurrence was detected in two patients (4.5%) after CAA and in six patients (7.2%) after APR. The 5-year survival rate after CAA was 79.2% and that after APR was 72.6%. No significant difference was noted in the incidence of pelvic recurrence or the survival rates between the two operations. These results show that CAA could be an excellent reconstructive option in the treatment of lower rectal carcinoma for selected patients.

Cloning, sequencing, and expression of the Bombyx mori receptor for Bacillus thuringiensis insecticidal CryIA(a) toxin

Bacillus thuringiensis strains produce insect-specific Bt toxins. Bt CryIA(a) toxin binds to a 175-kDa glycoprotein (BtR175) on the microvillus membranes of columnar cells in the Bombyx mori midgut and causes lysis of the cells. BtR175 was purified, and its cDNA was cloned. The cDNA encodes a newly identified 193.3-kDa preproprotein form of BtR175 that includes nine extracellular cadherin repeats, a 23.5-kDa membrane-proximal domain, a membrane-spanning region, and a 13.6-kDa cytoplasmic domain. Spodoptera frugiperda cells transfected with a recombinant baculovirus DNA carrying the cDNA produced a 175-kDa protein that reacted with anti-BtR antibodies and the Bt CryIA(a) toxin.

Identification of Bombyx mori midgut receptor for Bacillus thuringiensis insecticidal CryIA(a) toxin

As part of a study of the mechanism by which Bacillus thuringiensis insecticidal crystal protein acts, a Bombyx mori receptor to the CryIA(a) toxin specific for lepidopterans was examined. Histological examination showed that the toxin acted on the brush-border membrane of the midgut columnar cells and broke its infolding structure, causing cell lysis. The membrane vesicles were purified, and a 175-kDa protein binding the toxin was found that accounted for some 0.015% of membrane proteins. The protein, designated BtR175, was a glycoprotein that reacted with concanavalin A. Anti-BtR antibodies inhibited the binding of toxin to membrane vesicles in vitro and decreased the effect of the toxin to silkworms in vivo. BtR175, although found in the gut, was not found in fat bodies, integument, or silk glands. These results indicated that BtR175 was the receptor protein for the insecticidal toxin. Proteins (137 and 107 kDa) binding the CryIA(a) toxin also were found in the gut membranes of Tenebrio moritor larvae, a coleopteran not sensitive to the toxin. The specificity of the toxin could not be explained only in term of the existence of its binding protein.

Purification and characterization of Bombyx mori chitinases

Two isozymes of chitinase (EC 3.2.1.14) were purified from the fifth-instar larvae of Bombyx mori by chromatography on DEAE-Cellulofine A-500, hydroxylapatite, Butyl-Toyopearl 650M, and Fractogel EMD DEAE 650 (M). These two isozymes were glycoproteins with different apparent molecular masses of 65 and 88 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimum pHs of the 65 and 88 kDa chitinases were 5.5 and 6.5, respectively, towards a short substrate, N-acetylchitopentaose (GlcNAc5), whereas their high activities were observed in a wide pH range between 4 and 10 towards a longer substrate, glycolchitin. Steady-state kinetic analysis of these chitinases was performed using a series of N-acetylchitooligosaccharides (GlcNAcn, n = 2-6) and glycolchitin as the substrates. Kinetic parameters for both chitinases could be obtained in the hydrolysis of glycolchitin, but not in that of N-acetylchitooligosaccharides because of strong substrate inhibition. Both chitinases similarly hydrolysed N-acetylchitooligosaccharides except for GlcNAc2 as follows: GlcNAc3 to GlcNAc plus GlcNAc2, GlcNAc4 to two molecules of GlcNAc2, GlcNAc5 to GlcNAc2 plus GlcNAc3, and GlcNAc6 to GlcNAc2 plus GlcNAc4 as well as two molecules of GlcNAc3. These results suggest that these chitinases are endo-type hydrolases, and preferred the longer-chain N-acetylchitooligosaccharides. With respect to activity, the 65 kDa chitinase was 1.7-fold more active than the 88 kDa chitinase with regard to the initial velocity in the reaction of 0.1 mM N-acetylchitooligosaccharides (GlcNAcn, n = 3-6), whereas in the overall reaction of glycolchitin (kcat/K(m)), the 88 kDa chitinase was four times more active than the 65 kDa chitinase. Regarding the affinity (1/K(m)) to glycolchitin, the affinity of the 88 kDa chitinase was 5.8-fold higher than that of the 65 kDa chitinase. The protein amino acid and gene nucleotide sequences were partly determined. Both N-terminal amino acid sequences of the 65 and 88 kDa chitinases were identical as ADSRARIVXYFSNWAVYRPG. The partial amino acid (113 amino acids) and nucleotide sequences (278 nucleotides) analysed from a mixture of 65 and 88 kDa chitinases included the two conserved regions of the family of 18 glycosyl hydrolases. All these results suggest that the B. mori chitinases are similar to Manduca sexta chitinase in primary structure and kinetic behaviour, and may be involved in the initial and intermediate stages of chitin degradation.

Surgical treatment for patients with pulmonary metastases after resection of primary colorectal carcinoma

BACKGROUND

The optimum treatment for patients with pulmonary metastases from colorectal carcinoma is still controversial.

METHODS

To evaluate the results of pulmonary resection in 22 patients with pulmonary metastases after resection of primary colorectal carcinoma, patients' characteristics were examined retrospectively. Eighteen patients had a solitary metastatic lesion and four had two lesions.

RESULTS

Postthoracotomy recurrence occurred in 17 of the 22 patients (77.3%), and showed no correlation with the type of pulmonary resection. In 11 patients with a solitary lesion of less than 3.0 cm in greatest dimension, the 3- and 5-year postthoracotomy survival rates (PTSR) were 71.6% and 36.8%, respectively. Six of these patients received two or more thoracotomies for pulmonary recurrence. The 3-year PTSR for seven patients with a solitary lesion greater than or equal to 3.0 cm was 19.0%, and for the four patients with two lesions, 25.0%. A significant difference was noted in the survival rate according to both number and size of the metastatic lesions (P < 0.05).

CONCLUSIONS

The number and size of metastatic lesions appear to be important prognostic determinants. Repeated thoracotomy can prolong survival for selected patients.

Quantification of leucocyte elastase and cathepsin G in plasma by a simple method: effect of elastase in plasma levels of D-dimer and thrombomodulin

The purpose of this study was to determine levels of leucocyte elastase and cathepsin G in the plasma of patients in various pathological states, in which plasma increases or decreases in coagulation and fibrinolytic factors were seen. Simple methods were developed to measure the leucocyte proteinases and the results were correlated with conventional assays of coagulation and fibrinolytic factors. The total number of patients and total number of plasma samples examined were 340 and 1292, respectively. No correlation was observed between the plasma levels of elastase and cathepsin G, and plasminogen, fibrinogen and leucocyte counts. There was a weak overall correlation, however, between the leucocyte proteinases and each of the four parameters: D-dimer, thrombomodulin, antithrombin III and platelet count. There was a strong correlation between leucocyte proteinases and D-dimer and thrombomodulin in those patients with plasminogen levels within the normal range. Increased D-dimer levels, as well as plasmin, may suggest that elevated leucocyte proteinases contribute to elevated fibrinolytic mechanisms in these instances.

Pulmonary capacity in lung cancer patients prior to lung resection--comparison of the unilateral pulmonary artery occlusion test with expired gas analysis during exercise testing

We attempted to determine if expired gas analysis during exercise testing has equal value to the unilateral pulmonary artery occlusion test (UPAO). Sixty-four lung cancer patients were evaluated. We performed UPAO and measured mean pulmonary artery pressure (PPA) and cardiac output (C.O.) 15 min later, and calculated total pulmonary vascular resistance (TPVR). Expired gas analysis during exercise testing was performed, and the maximum oxygen consumption per unit body surface area (VO2max/m2) and the anaerobic threshold (AT/m2) were calculated. The patients were divided into two groups according to the PPA as follows: Group PPA(L) and Group PPA(H), and the TPVR as follows: Group TPVR(L) and Group TPVR(H). Comparative studies of the mean values of VO2max/m2 and AT/m2 were performed between the two groups. VO2max/m2 was significantly higher in Group PPA(L) than in Group PPA(H). VO2max/m2 was significantly higher in Group TPVR(L) than in Group TPVR(H). TPVR and VO2max/m2 showed no significant correlation, but a weak negative quadratic correlation with the equation y = 2276-246.6 logx was found. This result led a minimal acceptable levels for lung resection of Vo2max/m2 of 650 ml/min/m2 corresponding to the TPVR levels of 700 dyne.sec.cm5/m2.

Left partial anomalous pulmonary venous connection found during a lobectomy for lung cancer: report of a case

We report herein the case of a 68-year-old man in whom a partial anomalous pulmonary venous connection (PAPVC) was found during an operation for primary lung cancer. The preoperative clinical findings did not suggest a vascular shunt, and intraoperatively the anomalous vein was seen to drain only from the left upper lobe into the left innominate vein. The lower pulmonary vein connected normally, and there was no atrial septal defect nor any other anomalous condition. A left upper lobectomy with ligation of the anomalous connected vein was performed uneventfully. This type of PAPVC is extremely rare, and is especially noteworthy because there were no clinical signs.

Surgical treatment for patients with pulmonary metastases after resection of primary colorectal carcinoma

BACKGROUND

The optimum treatment for patients with pulmonary metastases from colorectal carcinoma is still controversial.

METHODS

To evaluate the results of pulmonary resection in 22 patients with pulmonary metastases after resection of primary colorectal carcinoma, patients' characteristics were examined retrospectively. Eighteen patients had a solitary metastatic lesion and four had two lesions.

RESULTS

Postthoracotomy recurrence occurred in 17 of the 22 patients (77.3%), and showed no correlation with the type of pulmonary resection. In 11 patients with a solitary lesion of less than 3.0 cm in greatest dimension, the 3- and 5-year postthoracotomy survival rates (PTSR) were 71.6% and 36.8%, respectively. Six of these patients received two or more thoracotomies for pulmonary recurrence. The 3-year PTSR for seven patients with a solitary lesion greater than or equal to 3.0 cm was 19.0%, and for the four patients with two lesions, 25.0%. A significant difference was noted in the survival rate according to both number and size of the metastatic lesions (P < 0.05).

CONCLUSIONS

The number and size of metastatic lesions appear to be important prognostic determinants. Repeated thoracotomy can prolong survival for selected patients.

Purification of a chitooligosaccharidolytic beta-N-acetylglucosaminidase from Bombyx mori larvae during metamorphosis and the nucleotide sequence of its cDNA

Three beta-N-acetylglucosaminidase (catalyzing hydrolysis of p-nitrophenyl-beta-D-GlcNAc) were purified from the integument tissue of Bombyx mori larvae during metamorphosis into pupae. The largest enzyme (66 kDa by SDS-PAGE, 126 kDa by gel-filtration chromatography) reacted with chitooligosaccharides to produce GlcNAc. A full-length cDNA encoding this chitooligosaccharidolytic beta-GlcNAcase was isolated. Based on the amino acid sequence deduced from the nucleotide sequence, the pre-beta-GlcNAcase was found to consist of 596 amino acid residues including a characteristic signal peptide of 23 residues and have an M(r) of 68,212. Homoloyg search and limited proteolytic digestion showed that the enzyme has a C-terminal 58-kDa catalytic domain very similar to that of human lysosomal beta-hexosaminidase that is responsible for hydrolyzing gangliosides. Two other enzymes (composed of 58-kDa and 48-kDa polypeptides, respectively) did not hydrolyze chitooligosaccharides, and were not proteolytic fragments from the largest enzyme judged by amino acid sequencing analyses. Natural substrates for the beta-GlcNAcases are unknown.

[The simultaneous evaluation of preoperative cardiopulmonary functions of esophageal cancer patients in the analysis of expired gas with exercise testing]

By analyzing expired gas with exercise testing, we examined the relationship between test results and postoperative cardiopulmonary complications. The analysis was evaluated for its accuracy and reliability in comparison with general pulmonary function tests including spirometry, flow volume curves, diffusing capacity and arterial blood gas analysis. Enrolled were 52 of patients admitted between a period from 1991 to 1993 for thoracic esophageal cancer, who underwent a radical operation of right thoracolaparotomy. Patients were divided into two groups according to postoperative cardiopulmonary complications; one with complications (group C, n = 11) and the other without complication (group NC = 41). The two groups were compared in maximum oxygen consumption (VO2 max)/m2, anaerobic threshold (AT)/m2, VC/m2, %VC, FEV1.0/m2, V25/m, V50/V25, %DLCO and PaO2. In the results, there were significant differences between the two groups only in VO2 max/m2 (p < 0.001), AT/m2 (p < 0.001), and V50/V25 (p < 0.05), while there were no significant differences between the two groups in VC/m2, %VC, FEV1.0/m2, FEV1.0%, V25/m, %DLCO or PaO2. The above results suggest that analysis of expired gas with exercise testing is able to measure easily both cardiac and pulmonary reserve forces, which conventional pulmonary function tests are unable to do, and is evaluating surgical indications for esophageal cancer patients and predicting postoperative cardiopulmonary complications.

[Pre-operative screening tests for lung cancer using the analysis of expired gas with exercise testing--principally VO2 max/m2]

The analysis of expired gas with exercise testing was conducted preoperatively with lung cancer patients in order to examine the relationship between maximum oxygen consumption (VO2 max) and postoperative complications, determining the cut-off of VO2 max/m2. The usefulness of the test as a preoperative screening test for both pulmonary ventilation and circulation was evaluated in comparison to pulmonary ventilation tests with spirometry and pulmonary circulation tests with Swan-Ganz catheter. Preoperative VO2 max/m2 was calculated from VO2 max in 111 patients with lung cancer who underwent lobectomy of more than one lobe. Also preoperatively conducted were pulmonary ventilation tests by spirometry and pulmonary circulation tests using the Swan-Ganz catheter to measure VC, %VC, FEV1.0, FEV1.0%, mean pulmonary arterial pressure (PPA) and cardiac output coefficient (C.I.). Form theses measurements, VC/m2, FEV1.0/m2 and total pulmonary vascular resistance (TPVR) were calculated. After the cut-off values of VO2 max/m2 were set tentatively at three stages, 600, 650 and 700 ml/min/m2 based on the incidence of postoperative complications, the 111 patients were divided into two groups in each cut-off value; one with VO2 max/m2 greater than the cut-off value and the other less than the cut-off value. Comparison of measurements obtained by spirometry between the two groups disclosed significant differences (p < 0.001) in VC/m2, %VC and FEV1.0/m2 in all cut-off values. Similarly, comparison of measurements obtained using the Swan-Ganz catheter between the two groups yielded significant differences (p < 0.05 to p < 0.01) in PPA and TPVR in all cut-off values.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino acids and peptides. XXXVII. Synthesis of stereoisomeric nonapeptides corresponding to sequence 41-49 of eglin c and examination of their inhibitory activity against human leukocyte cathepsin G and alpha-chymotrypsin

A nonapeptide, H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OH, corresponding to sequence 41-49 of eglin c inhibited leukocyte cathepsin G and alpha-chymotrypsin with Ki values of 2.2 x 10(-5) and 7.2 x 10(-6) M, respectively, although eglin c itself inhibited leukocyte elastase, cathepsin G and alpha-chymotrypsin with Ki values of 6.0 x 10(-9), 5.5 x 10(-9) and 2.5 x 10(-9) M, respectively. The inhibitory activity of the nonapeptide decreased following incubation with cathepsin G due to the cleavage of the Leu45-Asp46 peptide bond. Therefore, Leu45 and/or Asp46 were replaced with D-amino acids and the inhibitory activities of the resultant nonapeptides were examined. Their inhibitory activities against cathepsin G and alpha-chymotrypsin were much weaker than those of the all-L-type nonapeptide, suggesting that the amino acids at the active site, Leu45 and Asp46 are required to be in the L-configuration for potent activity.

Pharmacokinetic behaviour in polymorphonuclear leucocytes of N,N-dimethylcarbamoylmethyl alpha,2-dimethyl-5H-[1]benzopyrano[2,3-b]- pyridine-7-acetate (Y-23023), a new prodrug type of anti-inflammatory agent, and indomethacin after oral administrations in rats

N,N-Dimethylcarbamoylmethyl alpha,2-dimethyl-5H-[1]- benzopyrano[2,3-b]pyridine-7-acetate (Y-23023) is a prodrug developed as a new non-steroidal anti-inflammatory drug (NSAID). Y-23023 is rapidly hydrolysed to an active metabolite, alpha,2-dimethyl-5H-[1]benzopyrano[2,3-b]pyridine-7-acetic acid (M1) following its absorption and then exhibits a strong anti-inflammatory activity. We have examined the pharmacokinetic behaviour in polymorphonuclear leucocytes (PMNs) of M1 and of indomethacin after oral administration to rats of Y-23023 and indomethacin, respectively. Y-23023 was rapidly absorbed, producing a mean Cmax (1.13 micrograms mL-1) of M1 after 1 h in plasma. Indomethacin was less rapidly absorbed, producing a mean Cmax (3.38 micrograms mL-1) after 3 h in plasma. The mean AUC of M1 and indomethacin in plasma were 5.45 micrograms h mL-1 and 22.49 micrograms h mL-1, respectively. The mean tmax, Cmax and AUC of M1 in PMNs were 1 h, 11.1 ng (41 pmol)/10(8) cells and 58.6 ng (164 pmol) h/10(8) cells, respectively. The same parameters for indomethacin in the PMNs were 3 h, 15.4 ng (57 pmol)/10(8) cells and 95.2 ng (266 pmol) h/10(8) cells, respectively. The PMNs/plasma ratio of M1 was about 2.8 times that of indomethacin. These results indicate that the association of M1, an active metabolite of Y-23023, from blood to the PMNs is greater than that of indomethacin.

The inhibitory effect of sulfated schizophyllans and related oligosaccharides on coagulation and fibrinolysis

Sulfated schizophyllans and sulfated oligosaccharides were prepared and their inhibitory effects on coagulation and fibrinolysis were examined. Some sulfated schizophyllans, which had a sulfur content of more than 10%, prolonged prothrombin time (PT) and thrombin time (TT). Interestingly, some sulfated schizophyllans and related oligosaccharides were able to inhibit plasmin toward fibrinolysis and amidolysis.

[Evaluation of the exercise capacity recovery process after lung cancer surgery by exercise test and expire gas analysis]

This study was conducted to evaluate the numerical changes and the recovery process in exercise capacity over time, and to establish new criteria that will objectively evaluate the recovery in exercise capacity after lung surgery using an expired gas analysis incorporating an exercise test. The subjects consisted of 47 patients that underwent curative resection (only lobectomy) for lung cancer in the four years from 1989 to 1992 that were able to undergo expired gas analysis incorporating an exercise test before and after surgery. The expired gas analysis were performed within one week prior to surgery and over a period from 14 to 449 days after surgery, maximum oxygen consumption (VO2max) and anaerobic threshold (AT) measured, and the VO2max/m2 and AT/m2 were calculated as an index by dividing by the body surface area (m2). In addition, in order to examine the changes in exercise capacity after surgery, the presurgical values were used as 100, and the rate of change after surgery found. These rate were divided into the following measuring times, and the postsurgical changes over time analyzed. The postsurgical measuring times were divided into five groups from 14-30 days (n = 11), from 31-90 days (n = 25), from 91-180 days (n = 8), from 181-270 days (n = 19), and greater than 271 days (n = 8) after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

[Prediction of performance status after pneumonectomy]

To predict performance status (P.S.) following pneumonectomy, patients with lung carcinoma underwent pre-surgical pulmonary function tests with spirometry and unilateral pulmonary artery occlusion test (UPAO test). Between 1980 and 1991, twenty-nine patients who had survived more than six months after surgery were selected for the study. These patients were divided into two groups according to P.S. measured at six months after surgery: 16 patients with P.S. 0 to 1 were in Group A, and 13 patients with P.S. 2 to 3 were in Group B. The results of the following tests obtained prior to surgery were compared for the two groups to predict post-surgical P.S.; vital capacity (VC), VC/m2, forced expiratory volume in 1 second (FEV1.0), FEV1.0/m2, predicted VC/m2 and predicted FEV1.0/m2 calculated with residual pulmonary segments, mean pulmonary arterial pressure (PPA) before UPAO and 15 minutes after UPAO, total pulmonary vascular resistance (TPVR) before and during UPAO, and rate of changes in PPA and TPVR. Results obtained were as follows: Group B demonstrated significantly higher TPVR (p < 0.05) before the UPAO, PPA (p < 0.05) and TPVR (p < 0.002) during UPAO, and rate of change in TPVR (p < 0.02) than those in Group A. There were no significant differences between the two groups for other test results. From these results, lowering of post-surgical P.S. might be predicted when the TPVR during UPAO was 350 dyne.sec.cm-5/m2 or more.

Effect of long-term aerobic exercise on helium-neon-laser-induced thrombogenesis in rat mesenteric arterioles and platelet aggregation

We have previously investigated the antithrombotic effect of aerobic exercise in rat arterioles and venules under conditions of variable exercise load. In the present study, rats were subjected to constant exercise of 90% maximal oxygen uptake for 30 min, 5 times a week for 2, 4, 8 or 18 weeks. Thrombotic tendency was assessed by the He-Ne-laser-induced thrombus formation method. Platelet aggregation, platelet adhesion, whole blood clotting time, fibrinogen levels and blood cell count were also measured. The thrombotic tendency in arterioles decreased significantly after 18 weeks training, but not in venules. Thrombotic tendency increased slightly after 2 weeks training though the differences were not significant. A significant decrease in collagen-induced platelet aggregation was observed after 18 weeks training. The results demonstrated that long-term aerobic training decreased the thrombotic tendency in rat arterioles and that this was partly due to decreased platelet aggregability.

Bioavailability study of commercial sustained-release preparations of diclofenac sodium in gastrointestinal physiology regulated-dogs

The gastrointestinal (GI) physiology of beagle dogs was regulated with a combined-treatment of intramuscular pentagastrin (10 micrograms/kg x 2) and intravenous atropine sulfate (0.02 mg/kg x 1). Here, the gastric acidity, the gastric emptying time and the small intestinal transit time in the regulated-dogs were respectively around pH 2, 0.7h and 4h, approximating those in healthy humans. The superiority of the regulated-dogs over the intact dogs was confirmed in comparative bioavailability studies by using two classes of commercial preparations. Both the conventional tablet and the sustained-release capsule of diclofenac sodium exhibited simple and similar average plasma concentration-time curves of free diclofenac in the intact dogs, while the latter preparation is reported to reveal a bimodal plasma curve of the drug in healthy humans. The regulated-dogs, however, permitted a bimodal average plasma pattern of the drug for the capsules due to an approximation of the GI physiology between humans and these classes of the dogs. The combined-treatment of beagle dogs with pentagastrin and atropine sulfate seems to supply a useful animal model in predicting the absorption characteristics of the sustained-release preparations and poor water-soluble drugs.

Application of poly-L-lysine to purification of leukocyte cathepsin G by affinity chromatography

Poly-L-lysine with molecular masses of 3.3-290 kDa increased the amidolytic activities of leukocyte elastase and cathepsin G at low concentration, but had little effect on the activities of pancreatic elastase, alpha-chymotrypsin, plasmin and thrombin. Highly purified cathepsin G was obtained from column of EAH Sepharose 4B or Suc-L-Tyr-D-Leu-D-Val-pNA-Sepharose (affinity chromatography) by elution with poly-L-lysine solution (0.4 mg/ml, molecular weight (MW.) 290000 or 2.2 mg/ml, MW. 3300). Leukocyte elastase, adsorbed to Suc-L-Tyr-D-Leu-D-Val-pNA-Sepharose, was not eluted with poly-L-lysine solution. The amino acid composition of purified cathepsin G has been determined.

Antithrombotic effect of ticlopidine on He-Ne laser-induced thrombus formation in rat mesenteric microvessels

The inhibitory effects of ticlopidine and acetylsalicylic acid (ASA) on thrombus formation in rat mesenteric microvessels were studied. The results were compared with the effect of the drugs on platelet aggregation in citrated whole blood. He-Ne laser-induced thrombus formation in arterioles and in venules was significantly inhibited by 100 mg/kg ticlopidine. In contrast, a higher dose of ASA (300 mg/kg) was needed to inhibit thrombus formation and the effects of ASA were observed only in arterioles and not in venules. In addition, although the inhibition by ASA in arterioles was not strong it followed a dose-dependent manner, suggesting that the differential effect of ASA on platelets and endothelium may not be evident in vivo. Ticlopidine and ASA strongly inhibited ADP-induced whole blood platelet aggregation, but not collagen- or thrombin-induced platelet aggregation.

Determination of leukocyte elastase concentration in plasma and serum by a simple method using a specific synthetic substrate

The concentration of leukocyte elastase (ELP) in plasma and serum was determined by an amidolysis method using a specific synthetic substrate for ELP, Suc-Ala-Tyr-Leu-Val-pNA. Results were compared with those using ELISA. ELP levels in plasma from healthy donors were similar to those determined by ELISA; however, the levels in serum were lower than those determined by ELISA. Correlation coefficients of ELP levels in plasma and serum as measured by the two methods were 0.75 (amidolysis) and 0.90 (ELISA). On the other hand, the correlation coefficient between serum ELP by the two methods was 0.83. Half of the ELP levels in plasma from 150 patients and serum from 400 patients were significantly elevated when compared with those from healthy donors, and the ELP elevation determined by amidolytic assay correlated with some variables in blood, namely fibrin(ogen)-degraded products, fibrinogen, GOT, GPT, gamma-GTP, LDH and leucine aminopeptidase. Despite the fact that the amidolysis method detects the alpha 2-macroglobulin-ELP complex while ELISA detects the alpha 1-antitrypsin-ELP complex, a comparative study showed amidolysis to provide sufficiently sensitive measurement of both plasma and serum ELP.

Amino acids and peptides. XXX. Synthesis of eglin c (41-49) and eglin c (60-63) and examination of their inhibitory activity towards human leukocyte elastase, cathepsin G, porcine pancreatic elastase and alpha-chymotrypsin

H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OH and H-Thr-Asn-Val-Val-OH, which correspond to the sequences 41-49 and 60-63 of eglin c, respectively, were synthesized by a conventional solution approach using the newly developed 6-chloro-2-pyridyl ester method. The inhibitory activities of the above two peptides against human leukocyte elastase, cathepsin G, porcine pancreatic elastase and alpha-chymotrypsin were examined in comparison with those of the corresponding methyl esters.