PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “POLYSACCHARIDES, BACTERIAL”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed1957

Strain differences in local hemorrhagic response (Shwartzman-like reaction) of mice to a single intradermal injection of bacterial polysaccharides.

A survey of inbred strains of mice was made to determine whether the phenomenon of dermal hemorrhagic necrosis, as described in rabbits by Shwartzman, could be elicited in mice by bacterial polysaccharide preparations of demonstrated activity in rabbits. The polysaccharide preparations used were obtained from cultures of S. marcescens, S. typhosa, Ps. aeruginosa, and H. pertussis. Ten of the strains tested were unreactive. Three strains of mice and one F(1) hybrid subline developed a hemorrhagic lesion at the site of injection of a single, relatively high intradermal dose of polysaccharide. Some increase in incidence of hemorrhagic lesions was obtained when the intradermal dose was followed in 24 hours by an intravenous injection. In the gross and microscopically, the skin lesion produced in mice resembled the Shwartzman reaction in rabbits. An adrenergic blocking agent, SY-28, and an anticoagulant drug, coumadin, both of which block the dermal Shwartzman reaction in rabbits, also blocked the hemorrhagic skin reaction in mice.

Animals↗
PubMed1995

Observation of the helical structure of the bacterial polysaccharide acetan by atomic force microscopy.

A method has been developed that has been found to give reproducible images of uncoated polysaccharides by Atomic Force Microscopy (AFM). Aqueous solutions of the polysaccharide are deposited as drops onto freshly cleaved mica surfaces, air dried, and then imaged under butanol. The method has been used to obtain images of the bacterial polysaccharide acetan. In regions within the deposited sample, where the molecules are aligned side-by-side, it has been possible to observe a periodic structure along the polysaccharide chain, attributable to the helical structure of acetan.

Acetobacter↗
PubMed1979

Bacterial polysaccharide synthesis: an experiment for the dental biochemistry laboratory.

A simple experiment is described for demonstrating the formation of a high molecular-weight polysaccharide from sucrose by a bacterial enzyme. The polysaccharide confers high viscosity on solutions. Dental students are encouraged to consider this as a component of the system leading to the formation of dental plaque and the initiation of carious lesions.

Biochemistry↗
PubMedDate not supplied

The bacterial polysaccharide tecogalan blocks growth of breast cancer cells in vivo.

The growth of supportive tissue during the progression of solid tumors is an absolute requirement for the nourishment of the tumor. The blockade of this proliferative response of normal tissues to the growing tumor should hence inhibit tumor progression. We have shown earlier, that the heparinoid pentosan polysulfate (PPS) can block tumor growth and neoangiogenesis induced by Kaposi's FGF as well as by other heparin-binding growth factors (HBGFs). We now report on the effects of a bacterial polysaccharide, tecogalan, on tumor xenografts of human breast cancer cells. Tecogalan inhibited FGF-dependent SW-13 cells in vitro very similarly to PPS. Growth factor-independent MDA-MB 231 cells were used in animal studies to assess the in vivo potential of tecogalan. Subcutaneous growth of tumors was inhibited by once weekly i.v. administration of tecogalan. PPS single weekly administration showed a similar effect. No gross side effects were observed. Based on our previous studies with these models, we conclude, that tecogalan acts by blocking HBGFs released from tumor cells. Interestingly, single weekly dosing of either PPS or tecogalan appears to be strikingly more efficacious than spreading the dose over several administrations. These findings with a novel compound, tecogalan, and a novel treatment regimen, PPS, suggests a different approach to planning of therapies with these types of drugs.

Adenocarcinoma↗
PubMed1999

Electron beam fragmentation of bacterial polysaccharides as a method of producing oligosaccharides for the preparation of conjugate vaccines.

End-group mediated conjugation of bacterial polysaccharides (PSs) to carrier proteins containing T-helper cell epitopes renders such polysaccharides immunogenic also in young infants. Optimal construction of such conjugate vaccines requires fragmentation of the PS prior to the coupling reaction. In the present study a general simple and inexpensive method for the fragmentation of PSs is presented. It is based on the irradiation of isolated PSs in an electron beam accelerator. Exposure of isolated pneumococcal capsular polysaccharides (PnPSs) to ionizing radiation resulted in their partial depolymerization in a radiation dose-dependent manner. Radiation, unlike sonication, generated PnPS fragments of molecular size lower than 50 kDa and as small as 1.5 kDa when high radiation doses were used. These PnPS fragments have terminal reducing groups that can be easily used for chemical activation and subsequent coupling to any chosen carrier protein. The radiation-produced PnPS fragments retained their antigenic epitopes, when compared to native, full-size PnPSs as determined by enzyme-linked immunoassay.

Animals↗
PubMed1991

Oral immunization with bacterial polysaccharide and adjuvant enhances antigen-specific pulmonary secretory antibody response and resistance to pneumonia.

Nosocomial pneumonia, often due to Pseudomonas aeruginosa, occurs frequently after haemorrhage and trauma, and contributes to the increased incidence of morbidity and mortality in this clinical setting. In order to determine if enhancement of bacterial antigen-specific secretory IgA (sIgA) titres in the lungs can increase resistance to P. aeruginosa pneumonia following haemorrhage, we investigated oral immunization strategies, using bacterial polysaccharides (levan, from Aerobacter levanicum, and P. aeruginosa polysaccharide type I) and adjuvant (cholera toxin and the B-subunit of cholera toxin), capable of increasing bacterial polysaccharide-specific pulmonary secretory antibody titres. Oral co-administration of 1000 micrograms levan and 10 micrograms cholera toxin resulted in increased titres of levan-specific sIgA in lung lavages and increased numbers of levan-specific pulmonary plasma cells, but no changes in serum anti-levan titres. Similarly, oral co-administration of 1000 micrograms P. aeruginosa polysaccharide and 10 micrograms cholera toxin produced increased anti-P. aeruginosa polysaccharide titres in lung lavages. Significant decreases in anti-levan pulmonary sIgA titres and in numbers of levan-specific pulmonary plasma cells were found when oral immunization with levan and cholera toxin was performed 4 days following haemorrhage, but not if the mice were immunized 8 h after blood loss. Although haemorrhage markedly increased the susceptibility of mice to P. aeruginosa pneumonia, significant protection from mortality could be achieved through oral immunization with 1000 micrograms P. aeruginosa polysaccharide and 10 micrograms cholera toxin 8 h after haemorrhage. These results demonstrate that haemorrhage induces marked alterations in bacterial antigen-specific pulmonary B-cell responses, which contribute to the increased susceptibility to infection in this setting.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1992

Evaluation of bacterial polysaccharide immune globulin for the treatment or prevention of Haemophilus influenzae type b and pneumococcal disease.

A human hyperimmune globulin termed bacterial polysaccharide immune globulin (BPIG) has been prepared from plasma donors immunized with Haemophilus influenzae type b (Hib), pneumococcal, and meningococcal vaccines. At a dose of 0.5 ml/kg, BPIG increased levels of antibody to Hib by greater than 0.15 microgram/ml within 4-6 h and by 2-4 micrograms/ml at 72 h. Thereafter, antibody declined, with a mean half-life of 27 days. BPIG treatment of Apache infants did not impair their active antibody responses to concurrently administered diphtheria-tetanus-pertussis or Hib oligosaccharide-diptheria CRM197 conjugate vaccines. In high-risk Apache infants, BPIG given at 2, 6, and 10 months of age provided significant protection from invasive Hib infection during infancy. Thus, BPIG may have utility in the prevention of Hib infections in high-risk patients who cannot be immunized adequately with Hib conjugate vaccines.

Antibodies, Bacterial↗
PubMed2001

Structure of the O-specific polysaccharide of Proteus vulgaris O4 containing a new component of bacterial polysaccharides, 4,6-dideoxy-4.

A high-molecular-mass O-specific polysaccharide was obtained by mild acid degradation of Proteus vulgaris O4 lipopolysaccharide followed by GPC. The polysaccharide was studied by chemical methods along with 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, H-detected 1H,13C HMQC, and 1H,13C HMBC experiments. Solvolysis of the polysaccharide with trifluoromethanesulfonic (triflic) acid resulted in a GlcpA-(1 --> 3)-GlcNAc disaccharide and a novel amino sugar derivative, 4,6-dideoxy-4-[N-[(R)-3-hydroxybutyryl]-L-alanyl]amino-D-glucose [Qui4N(HbAla)]. On the basis of the data obtained, the following structure of the tetrasaccharide repeating unit of the O-specific polysaccharide was established: --> 4)-beta-D-GlcpA-(1 --> 3)-beta-D-GlcpNAc-(1 --> 2)-beta-D-Quip4N(HbAla)-(1 --> 3)-alpha-D-Galp-(1 -->. This structure is unique among the O-specific polysaccharides, which is in accordance with classification of the strain studied in a separate Proteus serogroup.

Animals↗
PubMed1996

Bacterial polysaccharide synthesis and gene nomenclature.

Gene nomenclature for bacterial surface polysaccharides is complicated by the large number of structures and genes. We propose a scheme applicable to all species that distinguishes different classes of genes, provides a single name for all genes of a given function and greatly facilitates comparative studies.

Computer Communication Networks↗
PubMed1988

Prevention of pneumococcal otitis media in chinchillas with human bacterial polysaccharide immune globulin.

Clinical and experimental observations suggest that immune globulin may prevent otitis media (OM) in children. We performed experiments in chinchillas to test the hypothesis that human bacterial polysaccharide immune globulin (BPIG) might prevent OM caused by Streptococcus pneumoniae. Animals were given BPIG or saline intraperitoneally on day 0. On day 3 the epitympanic bulla was inoculated with S. pneumoniae type 7F. All 12 saline-treated and none of 12 BPIG-treated animals developed pneumococcal OM by day 7 (P less than 0.0001). Bacteremia developed in 6 of 12 saline- and 0 of 12 BPIG-treated animals (P = 0.007). Death with pneumococcal OM occurred within 28 days in 5 of 12 saline- and 0 of 12 BPIG-injected animals (P = 0.02). A chinchilla-specific immunoassay was used to show that surviving saline-injected animals developed serum anticapsular antibody; BPIG-treated animals had no detectable response. At levels of anticapsular immunoglobulin G similar to those of human adults, BPIG given systemically prevented pneumococcal OM and disseminated infection in chinchillas. BPIG may be of value in preventing human bacterial infection and may also inhibit development of antibody if it affects local infection or colonization. Specific immunoglobulin G antibody may provide an important antibacterial defense of mucosal surfaces of the respiratory tract.

Animals↗
PubMed1980

Correlation between serum IgG-2 concentrations and the antibody response to bacterial polysaccharide antigens.

We measured serum concentrations of immunoglobulin classes and IgG subclasses in 53 patients who had completed treatment for Hodgkin's disease and in 10 healthy adults. We wished to determine the relation of these classes and subclasses to the subjects' antibody responses to bacterial polysaccharide and viral protein antigens. Mean levels of the IgG-2 subclass were significantly lower in patients treated with both radiation and chemotherapy than in controls (P less than 0.05). The level of IgG-2 before immunization correlated directly with the mean antibody response both to 11 pneumococcal antigens (r = 0.71, P less than 0.001) and to the Haemophilus influenzae Type b antigen (r = 0.40, P less than 0.01). The correlation between IgG-2 concentration and pneumococcal antibody response was also significant in the 10 healthy adults ( r = 0.70, P less than 0.05). The levels of no immunoglobulin class or subclass correlated significantly with antibody responses to influenza A/Victoria/75 and A/New Jersey/76 hemagglutinins, both of which are protein antigens. The serum concentration of IgG-2 appears to provide a marker for predicting the ability to produce antibodies to polysaccharide, but not viral protein, antigens.

Adult↗
PubMed1984

[Use of sodium nucleinate and its combinations with bacterial polysaccharides for preventing the nephrotoxic action of aminoglycoside antibiotics].

Possible prevention of the nephrotoxic effect of different doses of aminoglycoside antibiotics, such as monomycin, kanamycin and gentamicin was studied experimentally on chinchilla rabbits. Substances increasing the cell resistance (sodium nucleinate, prodigiosan and pyrogenal alone and sodium nucleinate combinations with the bacterial polysaccharides) were used. It was shown that sodium nucleinate prevented nephrotoxicity of the aminoglycosides in the doses 2.5 times higher than the therapeutic ones. The combined use of sodium nucleinate with pyrogenal or prodigiosan was most effective. It prevented the nephrotoxic effect of the antibiotics in the doses 5 times higher than the therapeutic ones.

Aminoglycosides↗
PubMed1994

Immune responses to bacterial polysaccharides: terminal epitopes are more immunogenic than internal structures.

Two types of dextran-protein conjugates can be produced depending on the size of dextran and the method chosen for coupling. Dextran of 4 x 10(4) molecular weight, randomly coupled to keyhole limpet hemocyanin evoked "incomplete" T cell-dependent (TD) immune responses. This atypical response only affected the dextran epitope since the response to the protein carrier was as expected for TD secondary immune responses. A second type of TD conjugates can be derived by coupling dextran (Dx) of 10(3) Da to the protein chicken serum albumin (CSA) via the reducing end (CSA-Dx-1). Immunization with CSA-Dx-1 induced the classical pattern of TD immune responses. Interestingly, immunization with CSA-Dx-1 favored the production of antibodies directed against terminal structures of the dextran molecule. These results were also confirmed at the hybridoma cell level. In contrast to other protein-dextran conjugates, CSA-Dx-1 was able to induce anti-dextran antibodies in CBA/N mice and in neonatal animals. We have interpreted these results to mean that conjugates exposing carbohydrate terminal nonreducing end structures could be more "physiological" and able to be recognized by helper T cells. This opens a new possibility for the production of vaccines against bacterial polysaccharides.

Animals↗
PubMed1987

Prevention of Haemophilus influenzae type b infections in high-risk infants treated with bacterial polysaccharide immune globulin.

Apache Indian infants have a high frequency of Haemophilus influenzae type b (Hib) and pneumococcal infections. Forty percent of Hib infections in these infants occur before the age of six months, when active immunization may not be protective. To evaluate the efficacy of passive immunization with a human hyperimmune globulin (bacterial polysaccharide immune globulin [BPIG]) prepared from the plasma of immunized adult donors, we randomly assigned 703 infants in a double-blind fashion to receive 0.5 ml of BPIG per kilogram of body weight (n = 353) or 0.5 ml of saline (n = 350) intramuscularly at 2, 6, and 10 months of age. Hib-antibody levels were significantly higher in BPIG recipients than in placebo recipients at 4, 6, and 10 months of age (P less than 0.001). During the first 90 days after BPIG or placebo injection, no Hib or pneumococcal infections were detected in the BPIG group, whereas seven Hib infections (six cases of bacteremia and one of meningitis) and four pneumococcal infections (bacteremia) were detected in the placebo group (P = 0.007 and 0.06, respectively). During the fourth month, one case of Hib meningitis and two cases of pneumococcal bacteremia developed in the BPIG group, whereas there were no Hib or pneumococcal infections in the placebo group. We conclude that BPIG given at four-month intervals provided significant protection against serious Hib disease for three months, and that in high-risk infants it might be used alone, perhaps at three-month intervals, or together with active immunization.

Antibodies, Bacterial↗
PubMed1986

Antibody response to pretreatment immunization and post-treatment boosting with bacterial polysaccharide vaccines in patients with Hodgkin's disease.

Overwhelming sepsis is a serious complication of staging splenectomy in Hodgkin's disease. To define an optimal immunization strategy, 51 patients received 14-valent pneumococcal, Haemophilus influenzae type b, and meningococcal group C vaccines before therapy and 2 to 12 months after completion of therapy. Natural antibody levels to bacterial polysaccharide antigens and the response to immunization were normal or only minimally impaired in patients with Hodgkin's disease compared with findings in healthy adults. The antibody response was not affected by the timing of immunization relative to splenectomy but was frequently impaired if chemotherapy was begun less than 10 days after immunization. Both post-immunization and "natural" antibody declines were significantly greater in patients with Hodgkin's disease than in healthy adults; the magnitude of the decline was related to the intensity of therapy. A spontaneous rebound in antibody concentrations was not seen during the 12 months after treatment. Booster immunizations of all three vaccines given during this period also failed to elicit an antibody increase.

Adolescent↗
PubMed1992

Modulation of the posthemorrhage bacterial polysaccharide antigen-specific antibody response by interleukins 2 and 4.

Abnormalities in immune response play a major role in the increased susceptibility to infection after hemorrhage and trauma. Several studies have shown decreased release in vitro of interleukin-2 (IL-2) following blood loss. To better define in vivo the interactions between T and B cells, as well as the effects of treatment with the T cell-derived cytokines IL-2 and IL-4, mice were injected with concanavalin A at predetermined times posthemorrhage, and the percentages and numbers of splenic plasma cells producing antibody to the bacterial polysaccharide antigen levan (from Aerobacter levanicum) were determined. Decreased numbers and percentages of levan specific splenic plasma cells were found in animals treated with concanavalin A both immediately and 2 to 4 days after hemorrhage. Treatment in vivo with recombinant IL-2, but not IL-4 or anti-IL-2 receptor antibodies, following blood loss was able to increase the numbers of levan specific plasma cells to levels as high or higher than those found in normal, unhemorrhaged animals, but was unable to affect the decreased percentage of levan specific splenic plasma cells. These results suggest that the use in vivo of IL-2 may restore bacterial antigen specific antibody responses to normal levels after blood loss.

Animals↗