胶州湾放线菌的分离及其抗病原微生物的活性检测

采用涂布法,从胶州湾海泥样品中分离到224株放线菌菌株,并且从海水样品中分离到32株放线菌菌株。根据形态学特性,菌株被分成了7个组。同时利用杯碟法测定了它们的抗菌活性,其中约7％对金黄色葡萄球菌有活性,11％对八叠球菌有效,10％对大肠杆菌有效,11％对绿脓杆菌有效,2％对白色念珠菌有效,5％对隐球菌有效,6％对绿色产色链霉菌有效和6％对米赫毛霉有效。分离到的22％放线菌对所测定的病原微生物有抗性作用。我们的结果表明胶州湾放线菌能够产生对病原微生物有抗性作用的不同代谢物,这些代谢物可以作为筛选新颖天然产物的独特和丰富的资源。     

Booster vaccination against tetanus and diphtheria: insufficient protection against diphtheria in young and elderly adults

We have recently demonstrated that single shot vaccinations against tetanus and diphtheria do not lead to long-lasting immunity against diphtheria in elderly persons despite administration at 5 year intervals. In the present study we have immunized a group of young adults against tetanus and diphtheria to compare the pre- and 28 days post-vaccination immune responses in the young group with results of the same vaccination performed in an elderly group of a previous study. We also studied protection in both groups 5 years after vaccination. We compared antibody titers at all three time points and also analyzed the T cell responses in both age groups 5 years after vaccination.Before vaccination 9 % of the elderly persons were not protected against tetanus, and 48 % did not have protection against diphtheria. In the young group all participants were protected against tetanus, but 52 % were also unprotected against diphtheria before vaccination. 28 days after vaccination 100 % of all participants had protective antibody concentrations against tetanus and only a small percentage in each age group (<10 %) was unprotected against diphtheria. 5 years later, 100 % of both cohorts were still protected against tetanus, but 24 % of the young and 54 % of the elderly group were unprotected against diphtheria. Antibody concentrations against diphtheria measured by ELISA correlated well with their neutralizing capacity. T cell responses to tetanus and diphtheria did not differ between young and old persons. We conclude that booster vaccinations against tetanus and diphtheria according to present recommendations provide long-lasting protection only against tetanus, but not against diphtheria, independently of age. In elderly persons, the level of protection is even lower, probably due to intrinsic age-related changes within the immune system and/or insufficient vaccination earlier in life.     

Synthesis and in vitro microbiological evaluation of novel diethyl 6,6'-(1,4-phenylene)bis(4-aryl-2-oxo-cyclohex-3-enecarboxylates)

Novel bis cyclohexenone ester derivatives 14-19 were synthesized and characterized by their spectral data. In vitro microbiological evaluations were carried out for all the novel compounds 14-19 against clinically isolated bacterial and fungal strains. Compounds 15, 16, 18 against Staphylococcus aureus, 14, 15 against β-Haemolytic streptococcus, 15, 19 against Micrococcus luteus, 17, 18 against Salmonella typhii, 14, 17 against Shigella flexneri, 15 against Escherichia coli, 16 against Pseudomonas aeruginosa, 15, 18, 19 against Klebsiella pneumonia exhibited potent antibacterial activity at an minimum inhibitory concentration (MIC) value of 6.25 μg/ml, whereas compound 16 against Aspergillus flavus, 17 against A. niger, 16, 18 against Mucor indicus, 15, 17-19 against Microsporum gypseum revealed excellent antifungal activity at an MIC value of 6.25 μg/ml.     

Comparison of anticonvulsant effect of ethanol against NMDA-, kainic acid- and picrotoxin-induced convulsions in rats

The anticonvulsant effect of ethanol against N-methyl-D-aspartic acid-(NMDA), kainic acid-, and picrotoxin-induced convulsions was studied in rats. Ethanol (2 g/kg, ip) offered protection against these agents, and it was most effective against picrotoxin and least effective against kainic acid. MK801, NMDA receptor antagonist, also provided protection against these agents. However, it was most effective against NMDA and least effective against kainic acid. Ineffective doses of MK801 (0.1 mg/kg, ip) and ethanol (0.5 g/kg, ip), when administered concurrently, had a facilitatory anticonvulsant effect, thereby providing protection against mortality following severe convulsions induced by NMDA or picrotoxin, but not against kainic acid. The protective effect of ethanol against NMDA- and kainic acid-induced neurotoxicity, in contrast to picrotoxin-induced toxicity, was not reversed by imidazodiazepine, Ro 15-4513, an ethanol antagonist. Furthermore, Ro 15-4513 did not produce any proconvulsant effect with NMDA or kainic acid. These findings suggested that the anticonvulsant actions of ethanol may be attributed to its ability to antagonize NMDA-mediated excitatory responses and facilitate the GABAergic transmission.     

Enhanced antitumor activity and selectivity of lactoferrin-derived peptides.

A number of peptide analogs derived from the N-terminal alpha-helical region of bovine lactoferrin (LFB 14-31), were designed in order to investigate how deviating numbers and positions of positively charged residues and numbers of aromatic residues affected their activity against prokaryotic, normal and transformed eukaryotic cells. Most of the LFB derivatives were highly active against both Escherichia coli and Staphylococcus aureus. The peptides were more active against the tumor cell lines MethA, HT-29 and MT-1 than normal eukaryotic cells. The peptides that were most active against the tumor cell lines had all cationic residues concentrated in one sector of the helical structure. These peptides were less selective against the tumor cell lines than against normal fibroblasts. Quantitative structure-activity relationship studies showed that certain structural parameters affected toxicity against the tumor cell lines more than against fibroblasts. Peptides encompassing these parameters were slightly less active against tumor cells, but gained significant selectivity.     

Cysteine chloromethyl and diazomethyl ketone derivatives with potent anti-leukemic activity

A series of cysteine diazomethyl- and chloromethyl ketone derivatives has been synthesized and evaluated against human B-lineage (Nalm-6) and T-lineage (Molt-3) acute lymphoblastic leukemia cell lines. The chloromethyl ketone compounds showed potent cytotoxicity against these cell lines, with IC50 values in the low micromolar range. The best compounds were N-acetyl-S-dodecyl-Cys chloromethyl ketone (IC50 = 2.0 microM against Nalm-6, 2.3 microM against Molt-3) and N-acetyl-S-trans,trans-farnesyl-Cys chloromethyl ketone (IC50 = 3.0 microM against Nalm-6 and 1.4 microM against Molt-3).     

Antileishmanial dinitroaniline sulfonamides with activity against parasite tubulin

Novel dinitroaniline sulfonamides based on the herbicide oryzalin 3 were synthesized and evaluated for activity against the parasitic protozoan Leishmania donovani and against leishmanial tubulin, the putative antiparasitic target of oryzalin. A subset of these compounds possess more activity against both Leishmania and the target protein in vitro. Compound 20 displays improved potency against leishmanial tubulin and is 13.4-fold more active against L. donovani axenic amastigotes than oryzalin.     

Sensitivity and Resistance to Growth Promoting Agents in Animal Lactobacilli

The minimal inhibitory concentrations of 11 growth promoting agents were determined by agar-dilution method against 113 strains of lactobacilli isolated from caeca of pigs, cattle and poultry. Only Lactobacillus acidophilus strains were susceptible to avoparcin and all strains were resistant to copper sulphate. Resistance was noted in cattle and poultry strains against bacitracin, in pig strains against virginiamycin, and in pig and poultry strains against nitrovin. Resistance against carbadox, flavomycin, lincomycin, oleandomycin, spiramycin and tylosin was noted in strains from all three host species.     

Enhancing Blockade of Plasmodium falciparum Erythrocyte Invasion: Assessing Combinations of Antibodies against PfRH5 and Other Merozoite Antigens

No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC₅₀ values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte-binding antigens such as PfRH4, to inhibit the growth of a homologous P. falciparum clone. A combination of antibodies against PfRH4 and basigin, the erythrocyte receptor for PfRH5, also potently inhibited parasite growth. This methodology provides the first quantitative evidence that polyclonal vaccine-induced antibodies can act synergistically against P. falciparum antigens and should help to guide the rational development of future multi-antigen vaccines.     

Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid

Inhibition of 12 mammalian isoforms of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), CA I-XIV, with a series of phenols was investigated. The inhibition profile by phenols of these CAs was distinct from those of the sulfonamides and their isosteres, the main class of clinically used inhibitors. Phenol and some of its 2-, 3- and 4-substituted derivatives incorporating hydroxy-, fluoro-, carboxy-, amino-, cyano- and acetamido-moieties were generally effective low micromolar CA inhibitors, with inhibition constants in the range of 9.8-4003 microM against CA I, of 0.090-870 microM against CA II, of 0.71-885 microM against CA III, of 9.5-809 microM against CA IV, of 8.7-867 microM against CA VA, of 4.2-649 microM against CA VB, of 11.4-658 microM against CA VI, of 9.1-1359 microM against CA VII, of 8.8-517 microM against CA IX, of 4.1-598 microM against CA XII, of 12.2-697 microM against CA XIII and of 10.1-49.8 microM against CA XIV, respectively. The different mechanisms of inhibition by phenols as compared to sulfonamides, and their diverse inhibition profile for these mammalian isozymes, makes this class of derivatives of great interest for the design of compounds with selectivity and/or specificity for some of the medicinal chemistry targets belonging to this enzyme family.     

Regulation of cellular immune response against autologous human melanoma. I. Evidence for cell-mediated suppression of in vitro cytotoxic immune response

The potential existence of down-regulation of cytotoxic immune response against an autologous human melanoma line was investigated as a possible explanation for cytotoxic unresponsiveness against the autologous melanoma cells. The melanoma cell line, PJ-M, was established and lymph node resident lymphocytes (LNL) were isolated from a lymph node which was partially infiltrated with the melanoma cells. Autologous peripheral blood lymphocytes (PBL) were sensitized in in vitro co-culture (IVC) against radiated PJ-M cells in the presence or absence of PJ-M-sensitized LNL and enriched suppressor (OKT8+) or inducer (OKT4+) LNL populations, and were assayed for cytotoxicity in a 4-hr 51Cr-release microcytotoxicity assay. Significant cytotoxic response against PJ-M could be generated in the PBL, but not in the LNL. The addition of sensitized, unfractionated LNL, OKT8+, or OKT4+ LNL populations abrogated cytotoxic response in the PBL against PJ-M. The suppression of cytotoxic response was induced selectively against the PJ-M targets, because IVC of PBL in the presence of the sensitized LNL did not affect the generation of polyclonal cytotoxic alloreactivities, nor did they abrogate the generation of cytotoxic response against allogeneic targets in IVC against the corresponding allogeneic targets. These results suggest the possibility that cytotoxic immune response against the autologous melanoma cells might have been suppressed by the individual's own immunoregulatory circuit.     

Histamine-sensitizing Factor, Mouse-protective Antigens, and Other Antigens of Some Members of the Genus Bordetella

The three species of the genus Bordetella-B. pertussis, B. parapertussis, and B. bronchiseptica-have many antigens in common. Studies on representative strains of these species have shown that there are only a few specific antigens in each species. Whole-cell vaccines and extracts from B. pertussis contained specific mouse-protective antigen and a histamine-sensitizing factor. In addition, whole-cell vaccines and some saline extracts protected mice against intracranial challenge with B. bronchiseptica. Cells and a saline extract of B. parapertussis also protected against B. bronchiseptica but not against B. pertussis. Whole cells of B. bronchiseptica protected against B. bronchiseptica, but only one of three saline extracts protected against this challenge. Neither whole cells nor saline extracts from B. bronchiseptica protected against B. pertussis. The antigen in B. pertussis responsible for cross-protection against B. bronchiseptica was less resistant to heat than the protective antigen in B. bronchiseptica. Since histamine-sensitizing factor was not detected in B. bronchiseptica or B. parapertussis cells or extracts, this factor is not required to protect mice against B. bronchiseptica challenge. Whether B. pertussis vaccines protected against B. bronchiseptica by a nonspecific mechanism was not established, but it is clear that the specific antigen responsible for protection against B. pertussis was found only in B. pertussis and not in B. bronchiseptica or B. parapertussis.     

Passive protection against rotavirus-induced diarrhea by monoclonal antibodies to surface proteins vp3 and vp7.

Monoclonal antibodies directed against two rotavirus surface proteins (vp3 and vp7) as well as a rotavirus inner capsid protein (vp6) were tested for their ability to protect suckling mice against virulent rotavirus challenge. Monoclonal antibodies to two distinct epitopes of vp7 of simian rotavirus strain RRV neutralized RRV in vitro and passively protected suckling mice against RRV challenge. A monoclonal antibody directed against vp3 of porcine rotavirus strain OSU neutralized three distinct serotypes in vitro (OSU, RRV, and UK) and passively protected suckling mice against OSU, RRV, and UK virus-induced diarrhea. The role of vp3 in eliciting protection against heterotypic rotavirus challenge should be considered when developing a vaccine with cloned rotavirus genes. Alternatively, immunization with a reassortant rotavirus containing vp3 and vp7 from two antigenically distinct rotavirus parents might protect against diarrhea induced by two or more rotavirus serotypes.     

Effect of selected anthelmintics on three common helminths in the brown pelican (Pelecanus occidentalis)

The effect of selected anthelmintics (albendazole, fenbendazole, piperazine dihydrochloride and clorsulon) against three major helminths (Contracaecum multipapillatum, Mesostephanus appendiculatoides, and Phagicola longus) were studied in 29 brown pelicans (Pelecanus occidentalis). Albendazole and fenbendazole were highly effective against all three parasites. Clorsulon had moderate effect against M. appendiculatoides and poor effect against C. multipapillatum and P. longus. Piperazine dihydrochloride had no effect against these helminths.     

Synthesis, spectral analysis and in vitro microbiological evaluation of novel ethyl 4-(naphthalen-2-yl)-2-oxo-6-arylcyclohex-3-enecarboxylates and 4,5-dihydro-6-(napthalen-2-yl)-4-aryl-2H-indazol-3-ols

A series of ethyl 4-(naphthalen-2-yl)-2-oxo-6-arylcyclohex-3-enecarboxylates 8-14 and 4,5-dihydro-6-(naphthalen-2-yl)-4-aryl-2H-indazol-3-ols 15-21 were synthesised and characterised by their spectroscopic data. In vitro microbiological evaluations were carried out for all the newly synthesised compounds 8-21 against clinically isolated bacterial and fungal strains. Compounds 9, 12 and 20 against Staphylococcus aureus, 10, 12, 20 against β-haemolytic streptococcus, 11, 17 against Bacillus subtilis, 12, 16 and 20 against Vibreo cholerae, 13, 16 against Escherichia coli, 13, 16, 18, 19 against Salmonella typhii, 12, 18 against Shigella flexneri, 10 against Salmonella typhii, 10, 13, 17, 18 against Aspergillus flavus, 12, 17, 21 against Aspergillus niger, 12, 15, 17, 18, 20 against Mucor, Rhizopus and Microsporeum gypsuem exhibit potent antimicrobial activity.     

Primary antisera against selected steroids or proteins and secondary antisera against gamma-globulins--an available tool for studies of reproductive processes

This paper presents characteristics of different polyclonal antisera raised against several steroid and protein antigens: 1/ primary antisera against steroid hormones: estradiol-17beta (anti-E2), estrone (anti-E1), testosterone (anti-T), androstendione (anti-A4), cortisol (anti-F) and corticosterone (anti-B); 2/ primary antisera against porcine luteinizing hormone (anti-pLH) and against different forms of porcine pregnancy associated glycoproteins (anti-pPAG) - proteins produced by chorionic tissue; 3/ secondary monovalent antisera raised against rabbit gamma-globulins (Sm-r); 4/ secondary polyvalent antisera against rabbit, pig and quinea pig gamma-globulins mixed at a ratio 1:1:1 (Sp-rpq). All antisera described in the paper present sufficient quality to be routinely used in various RIA, ELISA or Western determinations in physiological and clinical studies of reproductive processes. The antisera against steroid hormones and pLH are available on request.     

Antiviral activity of south Brazilian medicinal plant extracts.

Brazilian plants are potential sources of useful edible and medicinal plants. Hydromethanolic extracts prepared from 54 medicinal plants used in folk medicine to treat infections were screened for antiviral properties against five different viruses (HSV-1, HSV-2, poliovirus type 2, adenovirus type 2 and VSV). Fifty-two percent of the plant extracts exhibited antiviral against one or more tested viruses. More specifically, 42.6% showed activity against HSV-1 (herpes simplex virus type 1), 42.6% against HSV-2 (herpes simplex virus type 2), 26% against poliovirus and 24% against VSV (vesicular stomatitis virus). None of the extracts was active against adenovirus. Trixis praestans (Vell.) Cabr. and Cunila spicata Benth. extracts were further characterized for antiviral activity.     

Several enzymic properties of the DNA-polymerase alpha complexes with antibodies

A highly specific rabbit antiserum against DNA polymerase alpha from regenerating rat liver (antigen AG 1) and an antiserum against the preparation of the enzyme proteolytic fragments possessing catalytic activity (antigen AG 2) were obtained. The enzyme neutralization test revealed that antibodies against AG 2 inhibit the DNA polymerase activity in a much stronger degree, than those against AG 1. Data from a kinetic analysis of the enzyme complexed with the antibodies against AG 1 suggest that the catalytic and binding sites for dNTP and free Mg2+ are altered. The value of apparent Km for activated DNA is unchanged in the DNA polymerase complexes with antibodies both against AG 1 and AG 2.     

Antibodies against outer membrane proteins in rabbit antisera prepared against Escherichia coli O26 K60.

Antibodies directed against the protein constituents of the outer envelope membrane of Escherichia coli O26 K60 were demonstrated in antisera elicited in rabbits against three different preparations of the bacterium. Outer membraned solubilized by sodium dodecyl sulphate were applied to the antisera in an interfacial precipitin test, followed by polyacrylamide gel electrophoretic analysis of the resulting immunecomplexes. Protein profiles showed a complete outer membrane protein pattern, indicating the antigenic character of these proteins. Antisera containing antibodies against outer membrane proteins and free of reactive antibodies against lipopolysaccharide showed relatively low agglutinating activities against the bacteria. The antibodies against the protein constituents of the outer membrane belong mainly to the 7S class immunoglobulins, as indicated by 2-mercaptoethanol treatment of the antisera.     

Comparative susceptibility to anthelmintics of Brugia pahangi in jirds infected by different methods

It is possible to infect jirds with Brugia pahangi by three methods. Infective larvae (L3) can be injected either intraperitoneally (ip), when adults develop in the peritoneal cavity, or sub-cutaneously (sc), when they develop in the lymphatics or the heart and blood vessels associated with the lungs. Alternatively adult worms which have been grown in the peritoneal cavities of jirds can be implanted into the peritoneal cavities of other jirds. This latter system has been widely used for screening for new filaricides. We have compared the activity of 9 macrofilaricidal compounds against these 3 types of infection. Mebendazole and albendazole were more active against implanted adults than against L3 induced adults in the peritoneal cavity. Oxibendazole, flubendazole, CGP24588A and oxfendazole were equally active against both types of worm. CGP20376, Mel Ga and Mel Ni were more active against adult worms derived from inoculated L3 than implanted worms. When comparing intra-lymphatic and ip adults (both derived from L3 infections and in the same jirds) albendazole and CGP20376 were active at the same levels against both types of infection. Mebendazole, flubendazole, oxfendazole, CGP24588A, Mel Ga and Mel Ni were more active against ip adults than intra-lymphatic adults. No drug was more active against intra-lymphatic adults than against adults.