Aldosterone antagonists. 1. Synthesis and activities of 6 beta,7 beta:15 beta,16 beta-dimethylene steroidal spirolactones.

Several derivatives of the highly active aldosterone antagonists dihydrospirorenone (2) and spirorenone (3) were synthesized. The purpose of these efforts was to prepare compounds exhibiting reduced endocrinological properties with the same or better aldosterone antagonistic activity than that of spirorenone. The 1 alpha,2 alpha-methylene derivative 20 has a similar aldosterone antagonistic potency compared to that of spirorenone but does not show decreased endocrinological side effects. Other substituents as in compounds 4-11, 15-19, and 21 sharply decreased the aldosterone antagonistic activity of 2 or 3, respectively.

Aerosol exposure of pigs to viable or inactivated Actinobacillus pleuropneumoniae serotype 9 induces antibodies in bronchoalveolar lining fluids and serum, and protects against homologous challenge.

A dose-defined nose-only inhalation system for pigs was used to study the immunogenic and protective potentials of a single aerosol application of viable or killed Actinobacillus pleuropneumoniae serotype 9. Respiratory volumes were measured for each pig to calculate inhaled individual doses. Eight pigs inhaled 107 CFU A. pleuropneumoniae CVI 13261 reference strain for serotype 9. Another eight pigs received an identical dose of killed actinobacilli. After three weeks the pigs and nonexposed controls were challenged with 108 CFU of the homologous strain by aerosol. Bronchoalveolar lavage (BALF) in pigs was performed during the experiment to obtain lavage samples for assessment of local antibodies. Isotype-specific antibody responses in serum and BAL fluids were measured by ELISAs based on whole-cell antigens. The protective efficacy of aerosol immunization was evaluated by clinical and post-mortem examinations. The controls developed fever and severe pleuropneumonia, whereas previously exposed pigs had less fever and less extensive gross pulmonary lesions. After the first aerosol exposure pulmonary IgM, and IgG antibodies reactive with A. pleuropneumoniae increased significantly in both aerosol exposed groups. IgA in BALF and serum concentrations of each Ig class were significantly increased in the group exposed to viable bacteria when compared to the non-exposed controls. After aerosol challenge a pronounced increase of systemic and pulmonary IgA, IgM, and IgG antibodies was detected in both exposure groups. Aerosol application of whole-cell A. pleuropneumoniae bacterins induced similar protective effects against aerosol challenge infection as administration of an identical dose of viable bacteria. Inhalation of A. pleuropneumoniae may lead to asymptomatic carriers in some pigs that could spread the disease under field conditions.

Efficacy of an immunomodulating drug in immunodeficient and immunocompetent mice.

Bacillus subtilis culture filtrate (BSKR) was examined for its immunomodulating ability in the immunodeficient beige mouse and the immunocompetent Han:NMRI mouse strain. Following various application schemes the mice were challenged either subcutaneously with Escherichia coli or intranasally with Streptococcus pneumoniae. The mortality rates and the median of survival time were determined. Following subcutaneous application of BSKR Han:NMRI mice challenged with E. coli showed a decrease in mortality regardless of the application scheme. Using the beige mouse a protective effect was observed only after single applications of relatively low doses. Using Sc. pneumoniae as the challenge organism, a subcutaneous application of BSKR caused a decrease in mortality only if it was given on the day prior to infection. In both infection models the intranasal application of BSKR and/or of saline proved to be beneficial by either significantly decreasing the mortality or considerably increasing the survival time of beige and Han:NMRI mice.

Intestinal and serum antibody response in gnotobiotic piglets to oral immunization with Escherichia coli.

The local and systemic immune response to a formolized E. coli oral vaccine was investigated in 13 gnotobiotic piglets. Beginning at ten days of age animals received a daily dose of 10(10) or 10(11) bacteria, on ten consecutive days. Intestinal loop tests with one animal of each group on day 26 showed protection which was more pronounced in the animal dosed 10(10) bacteria compared with the other immunized piglet. Immunoglobulin class-specific antibodies to O and K antigens were determined by ELISA technique. In serum no IgG or IgA antibodies were found, whereas IgM-anti O149 antibodies in both immunized groups reached their highest level at day 4 of dosing and decreased thereafter. IgM-anti K88 antibodies were first detected at day 10 of dosing. Both immunized groups had comparable serum levels at days 20 and 30. Also in gut secretion the IgM antibody response was predominant, and higher levels were found in the 10(10) group than in the 10(11) group. IgG and IgA antibody response were also detected in secretion.

Prevalence of aerobic bacteria in bronchoalveolar lavage fluids from healthy pigs.

Fiberoptic bronchoscopy was performed in pigs to assess bacterial contamination of bronchoalveolar lavage fluids (BALF) obtained by use of the method and to determine the aerobic bacterial species in bronchoalveolar airways of healthy pigs. Bacterial contamination of BALF caused by insertion of the bronchoscope was evaluated, using a chromogenic bacterial tracer strain, and was found to be 0.22% of total colony-forming units (CFU), with range between 0 and 1.6%. A total of 164 pulmonary-healthy pigs from 6 closed herds were selected. The BALF obtained from these pigs were examined bacteriologically. Bacteria could not be isolated from 10.4% of all BALF; 5.5% of the BALF samples yielded pure cultures; and 84.1% yielded mixed aerobic bacterial growth. In BALF from 29.2% of the pigs, < or = 5 x 10(2) CFU of bacteria/ml were isolated. The total number of bacteria in BALF from 50% of the pigs varied between 5 x 10(2) and 10(3) CFU/ml; 10.4% of BALF samples contained between 10(3) CFU/ml and 5 x 10(3) CFU/ml. More than 1 bacterial species were isolated from a single lung lavage of 84.1% of the pigs. Up to 6 species were isolated from a single BALF sample. A total of 443 bacterial isolates were differentiated into 25 bacterial genera and species. Samples of BALF yielded staphylococci (67.6%: Staphylococcus hyicus from 13.4% of the samples and S aureus from 2.4%), alpha-hemolytic streptococci (49.4%), Escherichia coli (42.1%), non-hemolytic streptococci (26.2%), Klebsiella spp (18.3%), micrococci (12.8%), and Coryneformes (11.0%). Other bacterial species were found, but less frequently.(ABSTRACT TRUNCATED AT 250 WORDS)

[Direct detection of Actinobacillus (Haemophilus) pleuropneumoniae in the lungs of swine]. / Direkter Nachweis von Actinobacillus (Haemophilus) pleuropneumoniae in Lungen von Schweinen.

By means of cultural examination, coagglutination test (CT) and indirect fluorescent-antibody-technique (IFAT) a total of 199 lung specimens from necropsy pigs from Northwestern Germany with symptoms of pleuropneumonia was examined for Actinobacillus (Haemophilus) pleuropneumoniae (AP). The CT was used to detect type specific antigens in lung extracts and the IFAT was performed on tissue sections. Both tests were found to be specific. Detection and identification of AP by either test were successful in 68 of 199 lung specimens. AP was isolated out of 40 lungs, antigen detection by CT was successful in 40 and by IFAT in 65 lung samples. In 26.5% of the positive samples AP was demonstrated only by IFAT. In 4.4% of the positive specimens AP was demonstrated only by cultural examination, but the detected serovars were not accounted in IFAT and CT. In 44.1% of the positive specimens AP was isolated or detected by all three techniques. The predominating serovar was serovar 9 followed by 2 and 7. One field isolate could be identified as serovar 3 and another one as serovar 10. Furthermore one isolate was untypable. IFAT and CT were limited for detection of serovars 2, 7 and 9. Detection of multiple serovars in few lung samples was successful only by IFAT. Indirect fluorescent-antibody-technique was found to be more sensitive than coagglutination test and cultural examination. On the other hand CT was found to be less time consuming and easier to evaluate than other tests. By this, coagglutination test seems to be preferable in examining large numbers of lung samples.