Antimutagenic activity of extracts from anticancer drugs in Chinese medicine

The antimutagenic activities of extracts of 36 commonly used anticancer crude drugs from Chinese herbs were studied by using the Salmonella/microsomal system in the presence of picrolonic acid or benzo[a]pyrene to test whether they contain direct or indirect antimutagens. Each crude drug was extracted with boiling water for 2 h, the method which is commonly used by Chinese people to prepare the drug for oral intake. The extracts of Pteris multifida P. showed the highest antimutagenic activity against picrolonic acid-induced mutation. The extracts of 6 other different kinds of Chinese herbs were shown to have a moderate antimutagenic activity against picrolonic acid-induced mutation, and they are: Actinidia chinensis P., Artemisia lavendulaefolia DC. and Crotalaria sessiflora L., Prunella vulgaris L., Paris polyphylla S. and Ampelopsis brevipedunculata T. The extracts of Smilax china L., Prunella vulgaris L. and Actinidia chinensis P. were demonstrated to inhibit the mutagenicity of benzo[a]pyrene completely. The 12 other kinds of extracts of Chinese herbs which had a moderate antimutagenic activity against benzo[a]pyrene were: Pteris polyphylla S., Ampelopsis brevipedunculata T., Duchesnea indica F., Gossypium herbaceum L., Lithospermum erythrorrhizon SZ., Artemisia lavendulaefolia DC., Selaginella doederleinii H., Dianthus superbus L., Centipeda minima ABA., Curcuma zedoaria R., Marsdenia tenacissima WA. and Kalopanax septemlobus K. Among them, there were 5 kinds of crude drugs, Actinidia chinensis P., Artemisia lavendulaefolia DC., Prunella vulgaris L., Paris polyphylla S. and Ampelopsis brevipedunculata T., containing antimutagenic factors against both picrolonic acid- and benzo[a]pyrene-induced mutation.

Enhanced production of hepatitis B virus surface antigen in mouse C127 cell on a bovine papillomavirus-metallothionein vector

We have constructed a recombinant plasmid pCPS12 containing the hepatitis B viral surface antigen (HBsAg) gene linked to the mouse metallothionein promoter on a BPV-pML2 vector. Two stable clones S12-8 and S12-2, obtained by transfection of the mouse C127 cells with pCPS12 propagated in dam+ dcm+ and dam- dcm- Escherichia coli respectively, exhibited different types of response to 5-azacytidine (5-aza-CR) and cadmium (Cd) induction. In S12-8, the productivity of HBsAg was enhanced by 5-aza-CR or 5-aza-CR plus Cd, but not by Cd alone. In S12-2, the expression of HBsAg was not affected by 5-aza-CR but was induced by Cd in the presence or absence of 5-aza-CR. This suggests that methylation may be important in controlling the HBsAg expression and the inducibility of Cd in the transfectants.

The isolation and purification of pre-S2 containing hepatitis B virus surface antigen by chemical affinity chromatography

A simple, rapid, and efficient method was developed to isolate and purify pre-S2 containing HBsAgs from the plasma of a single chronic carrier of HBsAg (adw) by ammonium sulfate fractionation, hydroxyapatite column chromatography, and polymerized human serum albumin-affinity column chromatography. About 500 micrograms of pre-S2 containing HBsAg was obtained from 140 mL of plasma containing 4,200 micrograms of HBsAg. Two purified pre-S2 containing HBsAgs were analyzed by SDS-polyacrylamide gel electrophoresis and their molecular weights were determined to be 31,000 and 68,000 respectively. No significant amount of HBsAg or its derivative was detected in the final product.

Prevalence and characterization of hippurate-negative Campylobacter jejuni in King County, Washington

A total of 593 strains of thermophilic Campylobacter species were isolated either from humans with diarrhea or from poultry in King County, Washington. Of these strains, 98 (52 hippurate-positive strains and all 46 of the hippurate-negative strains) were selected for further phenotypic characterization and genetic classification. Hippurate hydrolysis, the test typically used to differentiate Campylobacter jejuni and C. coli, did not always correlate with the genetic classification. All hippurate-positive strains were classified as C. jejuni. Of the hippurate-negative strains, 20% were C. jejuni, 78% were C. coli, and 2% were C. laridis. Assuming that the remaining hippurate-positive strains were all C. jejuni, then hippurate-negative C. jejuni represented a small percentage (9 of 556 or 1.6%) of C. jejuni strains but a significant percentage (9 of 46 or 20%) of hippurate-negative strains. This finding suggests that hippurate hydrolysis should not be used as the sole criterion for differentiating thermophilic Campylobacter species, particularly when describing the disease states associated with these organisms.

Hepatitis type B virus DNA in patients receiving hemodialysis: correlation with other HBV serological markers

Possible presence of hepatitis type B virus (HBV) was assessed in 239 end-stage renal failure patients who were receiving long-term maintenance hemodialysis (average 30.8 months; duration: 1-94 months), and who had not shown any other symptom of HBV infection. Their HBV serological markers, including HBV DNA, were evaluated together with those of normal control individuals. HBV surface antigen (HBsAg) was detected in 42 of the 239 dialysis patients, 15 of whom also positive for HBV DNA (mean +/- SD = 56.2 +/- 23.7 pg/100 microliters of serum). HBV DNA was also found in 22 of the 197 (11.2%) dialysis patients who were negative for HBsAg, with an average of 36.2 +/- 19.0 pg/100 microliters of serum. This rate of detecting HBV DNA in HBV seronegative dialysis individuals was significantly higher than the rate of 1.83% found among healthy HBsAg(-) individuals. Among these 22 dialysis patients who were HBsAg(-) but HBV DNA(+), 15 were found to possess antibodies against HBsAg (anti-HBs) and/or antibody against HBV e antigen (anti-HBe). These data suggested that the absence of serum HBV antigen or the presence of antibodies against HBV markers might not be sufficient to identify possible HBV infection in immunocompromised hosts such as hemodialysis patients.

Deoxyribonucleic acid hybridization analysis for the detection of urogenital Chlamydia trachomatis infections in women

The presence of Chlamydia trachomatis-related deoxyribonucleic acid sequences in endocervical specimens of 317 women was analyzed by deoxyribonucleic acid hybridization techniques with deoxyribonucleic acid from C. trachomatis used as probes. Samples from 56 of 172 high-risk patients (32.6%) and 16 of 145 low-risk patients (11.0%) contained C. trachomatis-related deoxyribonucleic acid sequences. Direct detection of chlamydial antigen with enzyme-linked immunoassay on the same patients yielded positive rates of 26.3% and 7.3% for the high- and low-risk patients, respectively. C. trachomatis culture confirmed 86.3% of deoxyribonucleic acid-positive results and 84.0% of antigen-positive results. The overall sensitivities of chlamydial deoxyribonucleic acid and antigen assays were 91.7% and 68.8%, respectively, whereas the specificities were 95.3% and 94.7%. Results also suggested that the test of the C. trachomatis deoxyribonucleic acid correlated better with the female urogenital chlamydial infections than did the antigen test of C. trachomatis. The combined results of higher sensitivity in detecting the microorganism and better correlation with disease activity may make the deoxyribonucleic acid hybridization test a useful tool for the early and accurate diagnosis of C. trachomatis infections in female patients.

Large for gestational age: dilemma of the infant of the diabetic mother

A retrospective analysis was undertaken of 128 pregnancies (131 infants) complicated by diabetes; 66 (51 per cent) were Class A and 62 (49 per cent) Class B-D-F-R. 53.9 per cent of all infants were large for gestational age (LGA) and there were no differences between the classes of diabetics. LGA infants occurred with equal frequency in those diabetic patients with pregnancy-induced or chronic hypertension. Congenital anomalies occurred in 9.7 per cent with 11/12 in Class A, B, or C. Major neonatal morbidity included: 1) hypoglycemia: two (3 per cent) Class A and 21 (32.8 per cent) insulin-dependent mothers (P less than 0.01); and 2) respiratory distress syndrome: seven (5.3 per cent) and all were in classes B-F (P less than 0.05). Modern management of diabetes in pregnancy has, for unknown reasons, increased the incidence of LGA infants.

Characterization of hepatitis B e antigen from human breast milk

Hepatitis B e antigen (HBeAg) but not surface antigen (HBsAg) was detected in 20% of the milk samples taken from HBsAg carrier mothers by radioimmunoassay. The density of milk e antigen particles was peaked at 1.32 g/ml in CsCl gradient ultracentrifugation. HBeAg was found in 1.33 M and 3.24 M (NH4) 2SO4 precipitates from breast milk but neither of HBeAg in both precipitates showed exactly identical with serum-derived e antigen. Five bands of polypeptides with molecular weight of 8,000, 21,500, 37,000, 53,000 and 68,000 daltons were seen after polyacrylamide gel electrophoresis from the milk e antigen. In addition, the IgA was shown significantly high in HBeAg positive milk.

Studies on Ricinus communis lectin--carbohydrate interaction by means of affinity electrophoresis

The affinity gel electrophoresis of lectins purified from the seeds of Ricinus communis was studied. The mobilities of lectins on the gel showed various degree of retardation with their affinity toward their macromolecular ligand-agarose. Ricinus agglutinin which possessed the strongest affinity was retarded strongly, ricin C, and ricin B moderately, and ricin A, weakly. The concentrations of free moving ligand-galactose to reduce the retardation were also correlated very well with the potencies of affinities of lectins toward the ligand. The Kd values calculated from the retardations were 4.32 microM, 18.32 microM, 28.13 microM and 52.88 microM for ricinus agglutinin, ricin C, ricin B and ricin A respectively. Affinity gel electrophoresis was found to be a simple and quick method for studying the interaction of lectins with their ligands.

Studies on the antitumor lectins isolated from the seeds of Ricinus communis (castor bean)

Three toxic proteins and one agglutinin were purified from the seeds of Ricinus communis by a simple and fast method using Sepharose 4-B affinity chromatography followed by Sephadex G-100 gel filtration. The weakly adsorbed ricins A and B were retarded and eluted with the buffer from the affinity chromatographic column, while ricin C and ricinus agglutinin had to be eluted with 0.1 M galactose. The molecular weights of ricins A, B, and C were about 62,000 and that of ricinus agglutinin was 120,000, estimated by amino acid compositions and SDS gel electrophoresis. They all possessed two non-identical subunits: A and B chains linked by one disulfide bond. Their LD50 values were 4, 28, 14 and 112 micrograms per kg body weight of mice for ricins A, B and C and ricinus agglutinin, respectively. The amino acid compositions of the three toxins and their A and B subunits were very similar, but not identical, while ricinus agglutinin showed a different composition. Ricin A is a newly isolated lectin which has a strong inhibitory effect on the growth of tumor cells. By using cell cultures, it was demonstrated that the tumor cells were more sensitive to lectin than non-transformed cells, and that this could be caused by the higher binding affinity of lectin to tumor cells than to non-transformed cells.

Two-dimensional thin-layer chromatography for the specific detection of hippurate hydrolysis by microorganisms

Glycine, one of the end products of hippurate hydrolysis by microorganisms, was detected by a rapid, specific technique utilizing two-dimensional thin-layer chromatography. A loopful of growth of each organism from its suitable agar medium was washed, suspended, and incubated with 0.1% sodium hippurate for 30 min at 37 degrees C. The supernatant of the incubated suspension from each organism was then dansylated, and the dansyl derivatives were separated by two-dimensional thin-layer chromatography on polyamide sheets. Glycine, a product of hippurate hydrolysis, was detected under UV light. This technique does not require prolonged incubation and was found to be more specific and reliable than the standard ninhydrin reaction. In addition, it is inexpensive and can be easily conducted in a clinical microbiological reference laboratory. By this method, 100% (22/22) of Campylobacter jejuni and 0% (0/9) of Campylobacter coli reference strains were positive. In addition, 100% (13/13) of group B streptococci, 100% (24/24) of group D streptococci, and 90% (18/20) of Gardenerella vaginalis clinical isolates were positive for hippurate hydrolysis. This method is useful for the identification to the species level of Campylobacter organisms and the biotyping of Gardnerella organisms and for the detection of hippurate hydrolysis by unknown microorganisms.

Antitumor lectin-trypsin inhibitor conjugate

Concanavalin A (Con A) and trypsin inhibitor isolated from Acacia confusa were covalently linked with N-succinimidyl-3-(2-pyridyldithio)propionate. Con A-A. confusa trypsin inhibitor (ACTI) conjugate covalently bound (Con A-ACTI) retained about 42% of the trypsin inhibitory activity present in the native ACTI and had a higher hemagglutinating activity than did the native Con A. Con A-ACTI had a greater resistance to tryptic digestion than did the mixture of Con A and ACTI. The conjugate entered sarcoma 180 tumor cells, whereas the free ACTI did not. A single dose of the conjugate injected ip into noninbred N:NIH(S) white mice bearing sarcoma 180 had a remarkable effect of increasing the survival of tumor-bearing mice, while the mixture of an equivalent dose of free Con A and ACTI was not effective.

Identification of anti-human IgG monoclonal antibodies and monoclonal antibodies with confined subclass reactivity

In a previous paper, 4 hybridoma cell lines (1B3, 2D5, 2A4 and 2B6) secreting antibodies against heavy chain of human IgG were reported. In this paper a more detailed study of these McAbs was introduced. First of all they were studied with double immunodiffusion test in agarose and it was demonstrated that they were reactive against 3 distinct antigenic determinants of human IgG. This result was also confirmed by ELISA competition test. These McAbs were further analysed for human IgG subclass proteins and it was found that 1B3 McAb gave positive reaction with all subclasses of IgG while the other 3 possessed confined subclass reactivity, i.e. McAb 2A4 did not react with IgG3 (called non-IgG3 McAb), and both McAbs 2D5 and 2B6 did not react with IgG4 (called non-IgG4 McAb). By agarose immunodiffusion test it was shown that: (i) Only transparent precipitation line was formed when McAb reacted with IgG antigen, however, in agarose containing 2% PEG-6000, the transparent precipitation line becomes opaque; (ii) When a mixture of two McAbs against the same antigenic determinants (2D5 and 2B6) was placed into the same well, the precipitation line remained transparent, but if they were not identical (2A4 and 2D5), then opaque precipitation line formed even in the absence of PEG. It was suggested that this phenomenon should be used for preliminary analysis for the identity among McAbs. The confined IgG subclass McAb may be used for the preparation and purification of IgG3 or IgG4 protein before specific McAb against IgG3 or IgG4 is obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation and Characterization of a Lectin from Edible Mushroom, Volvariella volvacea

A lectin was purified from edible mushroom, Volvariella volvacea by extraction with 5% cold acetic acid in the presence of 0.1% 2-mercaptoethanol, followed by ammonium sulfate fractionation, and DEAE-C-52 and CM-C-52 column chromatographies. The molecular weight was measured to be 26,000, and the lectin consisted of two non-identical subunits as demonstrated by gel filtration and polyacrylamide gel electrophoresis. The lectin does not contain half-cystine, methionine, or histidine. The LD50 of the lectin is 17.5 mg per kg body weight of mice. The lectin has a moderate inhibitory effect on the growth of tumor cells.

Formation of mutagens in boiled pork extract

When boiled pork extract was heated under reflux at 102 degrees C for 4 hr mutagens, which were detected using Salmonella typhimurium strains TA98 and TA1538, were formed. The level of mutagenicity was dependent on the concentration of pork in the extract, the duration of boiling and on pH; the optimum pH for mutagen formation was found to be 9 to 11. Thin-layer chromatographic analysis showed that the mutagens formed in boiled pork extract were chromatographically distinguishable from benzo[a]pyrene and from the primary mutagenic pyrolysis products of tryptophan (3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole and of glutamic acid (2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole).

Induction of antitumor immunity by tumor cells treated with abrin

Abrin is known as a cytotoxic lectin. Immunization with Meth-A tumor cells which were treated in vitro with abrin induced a strong antitumor immunity in syngeneic BALB/c mice. The immunizing effect was stronger than that produced by an irradiated Meth-A tumor cell vaccine. Studies on the mechanisms of the immunizing effect with the abrin-treated tumor cells demonstrated that abrin acts as an immunoadjuvant. Furthermore, the regression of a growing Meth-A tumor was observed after abrin was injected into the tumor, while the induction of a strong antitumor immunity also occurred. It appears, therefore, that the antitumor effects of abrin are attributable to two kinds of activity: cytotoxicity and adjuvant activity.

Inhibitory effects of four isoabrins on the growth of sarcoma 180 cells

The four isoabrins were shown to be capable of inhibiting the growth of tumor cells in vivo when one-fifth of their median lethal dose was used. From the in vitro experiments, the doses required for 50% inhibition of protein biosynthesis are 3.2 pg, 45 ng, 32 ng, and 10 ng/ml for abrin-a, -b, -3, and -d, respectively. Except for abrin-b, a good correlation between the inhibitory effects of abrins on the tumor growth and protein biosynthesis was observed. These isoabrins show a moderate inhibitory effect on DNA biosynthesis.

Lectin derivatives of methotrexate and chlorambucil as chemotherapeutic agents

Methotrexate and chlorambucil, each covalently linked to either abrus agglutinin, abrin, ricinus agglutinin, ricin, or concanavalin A, were prepared. A single dose of the derivative injected ip into sarcoma 180-bearing noninbred N:NIH(S) white mice resulted in prolongation of the survival time and was more effective than an equivalent dose of free drug and lectin. Drug-lectin also showed a higher inhibitory effect on the DNA biosynthesis of the tumor cell than did an equivalent dose of the free drug and lectin.

Isolation of antitumor proteins abrin-A and abrin-B from Abrus precatorius

Two toxic proteins were purified from the seeds of Abrus precatorius by DEAE-A 50 and Sepharose 4B chromatography. One of them does not bind on the Sepharose 4B column (Abrin-b) and the other (Abrin-a) is eluted with 0.2 M galactose. The amino acid compositions and tryptic maps of these two proteins were similar, but not identical. The molecular weights estimated by SDS-gel electrophoresis were 67,000 for abrin-b as compared with 65,000 for abrin-a. In the presence of mercaptoethanol, both abrin-a and abrin-b gave rise to two bands. The lethal doses of abrin-a and abrin-b for mice recorded within 48 h were 10 and 25 microgram per kg of body weight respectively. Abrin-a at 0.8 microgram per ml concentration level agglutinated human 0-type erythrocytes, whereas abrin-b showed no such activity. Abrin-a at 5 microgram per ml concentration level agglutinated both the Sarcoma 180 cells and Ehrlich ascites tumor cells, but it required 150 microgram per ml for abrin-b. Both these two proteins at a sublethal dose could inhibit the growth of Ehrlich ascites tumor cells which were injected simultaneously with these proteins. 131I-abrin-a and 131I-abrin-b were able to bind Sarcoma 180 cells, and the binding of abrin-a could be inhibited by lactose, raffinose, galactose and rhamnose, but none of 15 sugars tested inhibited the binding of abrin-b.