Bacteremic pneumococcal pneumonia in one American City: a 20-year longitudinal study, 1978-1997.

A surveillance of bacteremic pneumococcal pneumonia was conducted in Huntington, West Virginia, from 1978 to 1997 to investigate case-fatality rates, incidence of disease, capsular types, and antibiotic usage. Our study population comprised consecutive inpatients admitted to the hospitals in Huntington, West Virginia, and included 45 children younger than 15 years and 328 adults. All blood isolates were serotyped by capsular swelling procedures; clinical characteristics, treatment, and outcome for all patients were abstracted from hospital charts. The overall case-fatality rate was 20.3%, with most deaths occurring among adults older than 50 years. Case-fatality rates peaked at 37.7% among patients 80 years of age and older. Only 1 of 45 (2.2%) children died. Case-fatality rates declined in each successive 5-year period, from 30.2% in 1978-1982 to 15.6% in 1993-1997. In that same period, incidence rates increased severalfold among children younger than 4 years to 44.5 cases per 100,000 population and among adults 70 years and 80 years of age and older to 38.5 and 76.2 cases per 100,000, respectively. Of the 34 serotypes isolated, 10 accounted for two thirds of the cases of pneumonia: 1, 4, 9, 14, 3, 6, 12, 5, 23, and 19 (in rank order). Chronic renal disease and arteriosclerotic heart disease increased the risk of death. Treatment regimens that included a macrolide and a penicillin or cephalosporin resulted in the lowest case-fatality rate in adults older than 50 years: 6% in 1993-1997. In conclusion, as bacteremic pneumococcal pneumonia evolved over time, the case-fatality rate decreased, its incidence increased, predominant capsular types changed, and treatment regimens that included a macrolide resulted in the lowest fatality rates.

Lack of effect of boar seminal vesicle fluid immunosuppressor factor on embryo development.

The effects of an immunosuppressive factor (ISF) isolated from boar seminal vesicle fluid on in vitro and in vivo mouse development were investigated. It was found that the zona pellucida of porcine and mouse oocytes pre-incubated with ISF reacted in indirect immunofluorescence with antibodies against ISF. Further results indicated that the boar ISF had no effect on embryo development.

Reactivities of a monoclonal antibody directed against an immunosuppressive molecule in boar seminal plasma.

Using a monoclonal antibody (LIS-4) to an immunosuppressive factor isolated from boar vesicular gland secretion it was determined that this gland secretes a tissue-specific immunosuppressive molecule that is absorbed onto the acrosome of spermatozoa during ejaculation. Absorption of the immunosuppressive molecule onto murine embryos at the 2-, 4-, 8-cell, morula and blastocyst stages in vitro was evaluated by indirect immunofluorescence. In vivo absorption was detected on the zona pellucida of murine embryos obtained from oviducts injected with the immunosuppressive molecule. Immunofluorescence revealed that the immunosuppressive molecule was not absorbed onto murine embryos after solubilization of the zona pellucida. There was no effect of the antibody to the immunosuppressive molecule on the ability of boar spermatozoa to penetrate the porcine zona pellucida.

Characterization of a new porcine differentiation antigen involved in the proliferative response to mitogens.

The cytotoxic monoclonal antibody (Mab) LIL 13 reacts with a widely distributed antigen that is expressed on 80-95% of swine peripheral blood mononuclear cells (PBMC) and a variety of lymphoid cell types. Using indirect immunofluorescence (IIF) the positive cells (75-100%) were divided between the bright, intermediate and dull populations. The remaining negative cell population contained B-cells, T-cells and probably null cells. Mab LIL 13 did not react with swine major histocompatibility complex (MHC) class I antigens (SLA) and did not inhibit E-rosette formation. Reactivity of LIL 13 with leukocyte function antigen 1 (LFA-1) was excluded by competitive IIF and cytotoxicity tests with cross-reacting anti-human CD 18 or anti-swine LFA-1-specific antibodies. Mab LIL 13 and complement treatment severely reduced mitogen-induced proliferative response to phytohaemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM) and lipopolysaccharide (LPS) (90-100%). In the absence of complement, LIL 13 partially reduced proliferation of cells by interfering with the capability of mitogens to bind to the corresponding surface receptor (LIL 13 followed by mitogens), and partially inhibited mitogenic proliferative response following post-treatment (mitogens followed by LIL 13). Biochemical analysis of the antigen using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed bands of approximately 180-190 kDa and 46-50 kDa under reducing conditions and 200 kDa and 46-50 kDa under nonreducing conditions.

Emergence of penicillin-resistant invasive pneumococci in a single American community.

Three decades ago, penicillin-resistant strains of Streptococcus pneumoniae were first reported. Since then, myriad penicillin resistant strains of S. pneumoniae have been identified worldwide and in the United States. No resistant or intermediate resistant strains have been reported in West Virginia because testing has not been done. Between 1983 and 1994, the authors' surveillance of invasive pneumococcal disease in metropolitan Huntington, West Virginia, identified 356 pneumococcal strains from blood and other usually sterile sites, including 110 strains belonging to serotypes 6, 9, 14, 19, and 23, the main serotypes exhibiting penicillin resistance. The authors tested these serotypes for penicillin susceptibility by the E-test. Sixteen (14.5%) strains of types 6, 9, 14, 19, and 23 exhibited intermediate resistance to penicillin. No highly resistant strains were identified. Most of the intermediate resistant strains of types 9, 14, and 23 were detected in epidemiologic years 1992-1994. The increasing number of intermediate resistant penicillin strains signals the need for routine testing of invasive pneumococcal strains for penicillin susceptibility and necessitates appropriate antibiotic usage.

Action of bull seminal vesicle ribonuclease on mouse leukaemic cells BP-8 and EL-4.

Bull seminal vesicle ribonuclease, when added in vitro to the suspension of ascitic leukaemic cells EL-4 and BP-8 for 2 hours at 37 degrees C and then transplanted to the abdominal cavities of mice, inhibitied the proliferation of these cells in vivo. When the temperature of the medium was decreased to 25 degrees C, AS RNase was bound to the leukaemic cell surfaces, but it exerted no inhibitory effect on BP-8 cells and showed a partial effect on EL-4 cells even after 24 hours. AS RNase administered to mice with leukaemic cells in diffusion chambers significantly decreased the number of cells inside the chambers as compared to the controls. The number of ascites cells was also significantly reduced after the injection of AS RNase for 1 week into mice with leukaemic cells implanted in the abdominal cavities. The reduction of cells in ascitic fluid did not cause a significant prolongation of survival of experimental mice. Only mice with transplanted BP-8 cells had significantly less cells in ascitic fluid and their survival was prolonged to 48 days in comparison with 25 days' survival in control mice after administration of pure AS RNase. In addition, AS RNase depressed the growth of solid tumours BP-8 and EL-4. AS RNase did not change the weight of body organs except the testes. Absorption experiments showed increased absorption of AS RNase by leukaemic cells BP-8 and EL-4 and by testes and spleen homogenates as compared with other body organs.

Action of A RNase and AS RNase on growth of cells in vitro.

The effect of bovine pancreatic A RNase and bull seminal vesicle AS RNase on proliferation of HeLa cells and LEP cells in vitro was studied. The ribonucleases were used in doses of 0.1, 1.0, 10.0, and 100.0 microgram per ml of medium and 100 000 inoculated cells. Proliferation was evaluated by the growth curves. Both in single and long-term experiments. A RNase in all doses used had no effect on cell proliferation, whereas AS RNase exerted inhibitory activity beginning with the dose of 10 microgram, and affected more markedly the LEP cells (a diploid non-malignant cell line) than the malignant heteroploid HeLa cells. When added to the cell suspension, AS RNase was shown by indirect immunofluorescence to bind to HeLa cell membranes in all phases of growth, whereas AS RNase was found on membranes of LEP cells only when they were derived from the log phase of growth.

Effect of native and modified bull seminal ribonuclease on tumour and testicular cells and phytohaemagglutinin-stimulated pig lymphocytes.

The carboxymethylated, oxidized and reduced forms of AS RNase inhibited transplantability and DNA synthesis of tumour cells BP-8 and EL-4 incubated in vitro. With tumour cells EL-4 the results under in vitro conditions did not not correspond to those obtained under the conditions in vivo. The survival of mice given injections of EL-4 cells and of the native and carboxymethylated AS RNase was only slightly prolonged. Mice that received intra-abdominally BP-8 cells and both carboxymethylated and oxidized and reduced forms of AS RNase survived two or three times longer than the controls. Succinylation and maleylation of AS RNase eliminated any antitumoral effect. Aspermatogenic activity of AS RNase was abolished by any modification of the molecule which had substantially reduced, or removed, the RNase activity. Neither native nor modified forms of AS RNase had an inhibitory effect on unstimulated pig lymphocytes. The DNA synthesis of PHA-stimulated lymphocytes was inhibited by the native and carboxymethylated AS RNase only. Bovine pancreatic A RNase had any inhibitory effect on neither tumour nor testicular cells.

Immunosuppressive effects of a synthetic polymer poly N-(2-hydroxypropyl)methacrylamide (Duxon).

Poly N-(2-hydroxypropyl)methacrylamide (Duxon) was studied as a substitute of blood plasma and was found to prolong significantly the survival of semiallogeneic skin grafts in mice and rats and to reduce MLC reactions of human lymphocytes. It did not inhibit the growth of lymphocytes and the growth of the fibroblast-like (diploid) or epithelioid (heteroploid) cell lines in tissue culture.

Immunogenetic studies in semi-inbred pigs.

Seventy-six siblings from 11 semi-inbred families of Landrace pigs (inbreeding coefficient 0.70-0.82) were used for transplantation of skin and renal allografts. The animals were selected with regard to the major histocompatibility complex SLA, alloantigenic systems SLB, SLC and blood groups. Using the test of the difference in mean level between two groups of observations, the influence of compatibility in the E blood group system on the survival of transplants was proved. The observed difference suggests that the E blood group complex or a linked locus behaves as a minor histocompatibility system. The induction of tolerance in piglets treated and non-treated with allogeneic sera from long-term liver recipients was also investigated. Large doses of sera did not exert any effect on skin graft survival.

Monoclonal antibodies specific for pig serum and cell surface IgM.

Two monoclonal antibodies were prepared which react specifically with pig serum immunoglobulin and with the population of B lymphocyte-bearing surface immunoglobulin. Comparison of our monoclonal antibodies with reagents specific for gamma, mu and alpha immunoglobulin chains in double immunodiffusion and immunoelectrophoresis revealed that the monoclonal antibodies recognise IgM in pig serum and mu chain or mu chain-like molecules on B lymphocytes. The monoclonal antibodies, designated LIG 2 and LIG 4, reacted positively with adult pig sera but not with fetal or precolostral sera or with sera from other animal species. LIG 2 and LIG 4 reacted with 15 per cent of cells from the peripheral blood lymphocyte population, 20.2 per cent of spleen cells and 20 per cent of lymph node cells, but did not react with pig erythrocytes, granulocytes or cells isolated from thymus, or with the lymphocytes of other species. Positive reactions were also found on lymphatic and intestinal tissue sections. No genetic polymorphism was found in the pig population revealed by the monoclonal antibodies. The monoclonal antibodies LIG 2 and LIG 4 may be useful for studying the pig immune system, especially as a standard reagent for measuring pig serum IgM and for the identification of positive B lymphocytes.

Development of a semi-inbred line of Landrace pigs. I. Breeding performance and immunogenetic characteristics.

During 15 years of inbreeding of pigs (Canadian Landrace) a semi-inbred line has been developed. The inbreeding coefficient (FX) is 0.84, which theoretically corresponds to between 8-9 generations of brother/sister matings. At the highest inbreeding level (0.84) the mean number of newborn piglets in the litter was 7.2 (5 litters, n = 36) including 5 stillborn (13.8%). The mean birth weight of the litter was 8.56 kg (5 litters, n = 31) the mean piglet birth weight was 1.23 kg and at the age of 21 days the mean weight of a litter was 33.24 kg with a mean piglet weight of 5.44 kg. During inbreeding, immunogenetic alloantigenic systems were investigated. Of 15 known erythrocyte systems, alleles of loci J, K, and of the most polymorphic system E, segregated. As to other immunogenetic systems (histocompatibility, leucocyte and allotypes) 2 SLA haplotypes (major histocompatibility complex) and 2 alleles of the SLC leucocyte system segregated. Allotransplants of the skin in SLA compatible siblings survived for a mean of 50.7 days (n = 77) compared with 10.8 days (n = 29) in non-inbred siblings. Tests of blastic transformation activated by T and B lymphocyte mitogens revealed a normal cell-mediated immune response. After immunization with some cell membrane alloantigens a normal humoral response was also recorded. All tested animals were halothane-resistant and tolerated a 10-min exposure to 5% without developing malignant hyperthermia. Depression due to inbreeding was manifested by a reduced reproductive ability (smaller number of piglets, frequent incidence of gonadal hypoplasia, diminution or loss of libido).

Identification of a variant subgroup A strain of respiratory syncytial virus.

During epidemiologic surveillance of children with respiratory syncytial virus (RSV) disease in Huntington, W.Va., we identified seven strains of a new variant subgroup A RSV (subgroup A-Var) by their reactions in an enzyme immunoassay with two anti-F monoclonal antibodies (MAbs) specific for two epitopes, F1 and F4, generated against the subgroup B RSV. The prototype strain of subgroup A and all other subgroup A field strains from that epidemiologic year failed to react with these two subgroup B MAbs. Additional enzyme immunoassays with 18 subgroup B anti-F MAbs specific for 14 epitopes showed that subgroup A-Var strains also reacted with a MAb specific for the subgroup B F2 epitope. In a radioimmune precipitation assay, the molecular size of the subgroup A-Var F2 subunit of the fusion (F) protein clearly differed from those of both prototype strains of subgroup A and subgroup B RSV. The molecular size of the F2 subunit of subgroup A-Var (24 kDa) was intermediate between the size of the F2 subunit of subgroup A (25 kDa) and that of subgroup B (23 kDa). However, the molecular sizes of the F1 subunits of both subgroup A and subgroup A-Var were identical (54 kDa) and slightly larger than those of the F1 subunits of both subgroups B1 and B2 (53 kDa). These data suggest that subgroup A-Var may represent a distinct RSV A subgroup, analogous to subgroup B1 and B2 RSV, and it is the first-identified naturally occurring subgroup A RSV with an F protein different from that of the prototype A RSV.

A 20-year epidemiological study of pneumococcal meningitis.

We conducted a retrospective analysis of 55 community-acquired Streptococcus pneumoniae meningitis illnesses in Huntington, West Virginia, from 1978 to 1997. Fourteen (36.8%) of 38 adults and 2 (11.8%) of 17 children died. Serotypes 6, 23, 3, and 18 accounted for 20 (41.7%) of 48 strains available for serotyping. Of 40 strains available for antimicrobial susceptibility testing, 1 serotype 19 and 1 serotype 23 strain showed intermediate resistance and a second serotype 23 strain showed high resistance to penicillin; all three patients survived. The case-fatality rates among adults who received penicillin alone, gentamicin in combination, or vancomycin and cephalosporin together were 57.1%, 55.5%, and 60%, respectively, and among those who received chloramphenicol or a third-generation cephalosporin, they were 11.1% or nil, respectively. No child died who received chloramphenicol or vancomycin. Two (33%) of 6 children died who received a third-generation cephalosporin; both were critically ill when initially treated. No child and one adult had received pneumococcal vaccine prior to becoming ill.

Effect of antibodies to boar spermatozoa on fertility in sows and rabbits.

Immunization of sows with boar spermatozoa had no effect on the sows' fertility or on the number of liveborn young from the first pregnancy. An effect was not recorded until the second pregnancy, when the number of stillborn young increased. The total number of young in the litters was not reduced. Pig and rabbit antibodies to boar spermatozoa had no negative effect on the fertilizing capacity of rabbit spermatozoa. The intravenous administration of antibodies against boar spermatozoa to inseminated female rabbits did not affect their fertility. If the antibodies were injected intramuscularly 7 days before and 10 days after insemination, degenerating fetuses were found in the uterus of inseminated female rabbits. After immunizing sows with boar spermatozoa, specific cellular immune reaction was not demonstrated.

Evaluation of vaginal malodor and efficacy of treatment by high performance ion exchange chromatography.

High performance ion exchange chromatography was employed to evaluate the presence of short chain organic acids in the vaginal fluid of a woman troubled by persistent foul vaginal odor, but who did not have typical bacterial vaginosis. The vaginal secretions from this patient were collected on a weighed cotton swab and eluted into water and extracted by acidified ether. Salts of the acids were back-extracted into aqueous solution and chromatographed on an H-form resin column and compared to commercially available standards. A strikingly large amount of caproic acid was found. The caproic acid disappeared after metronidazole therapy, and a subsequent follow-up chromatogram showed a predominance of lactic acid. The success of this technique in evaluating the present case suggests that such a method may prove useful in other types of vaginal infection.

Effects of chlorhexidine gluconate douche on normal vaginal flora.

The effects of a 0.5% aqueous chlorhexidine gluconate (CHG) douche on the normal vaginal flora of twenty healthy nonpregnant volunteers were investigated. The douche was applied in a premeasured 180-ml quantity daily for 7 consecutive days. Specimens for aerobic and anaerobic culture of the vaginal flora were obtained on 3 occasions from each volunteer, once before and twice after CHG use. The culture results were analyzed qualitatively and quantitatively. A blood sample was also collected within 24 h of the last CHG application to determine serum CHG concentration. Lactobacillus spp., Gardnerella vaginalis and Staphylococcus epidermidis were the most prevalent aerobic bacteria at all phases of the study and Bacteroides spp. were the most prevalent anaerobes. The composition of the normal flora was essentially the same 30 days after the last dose as the pretreatment flora. Small amounts of CHG were detected in the serum of all but one subject. No untoward effects on the participants were observed. Candida albicans counts were slightly higher, but prevalence was not significantly increased at the end of the study.