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At least 307 records · Page 17Linked to original sources
PubMed1978

Characterization of Pasteurella multocida isolates from the nares of healthy rabbits with pneumonia.

Pasteurella multocida was isolated from 42 of the 135 (31%) deep nasal swabs from clinically healthy conventional rabbits supplied by two vendors. The prevalences were significantly different among sex, age, and sources. The females and adults had higher prevalences when compared to males and juveniles, respectively. One vendor's rabbits had a prevalence of 41% while the other had 20%. Biochemically, only 24% of the 42 isolates decarboxylated L-ornithine, and 55% produced indol. All isolates were sensitive in vitro to several of the commonly used antibiotics, but most isolates were resistant to lincomycin, streptomycin, and sulfonamides. Typing with a hyaluronidase inhibition test revealed that 28 of the 42 (67%) isolates were type A. Type A was the major type isolate, whether the samples came from healthy rabbits or from rabbits with pyogenic lesions. The acriflavine flocculation test showed that two of the 42 (5%) isolates were type D. Although none of the 42 isolates were positive to both hyalurondase and acriflavine tests, 12 of the 42 (29%) isolates were negative to both tests, indicating that these isolates were not typeable by these two methods. The demonstration of more than one capsular type of Pasteurella multocida in rabbits indicates the need for more extensive studies on this important rabbit pathogen.

Acriflavine↗
PubMed1989

[The liver and rheumatoid arthritis].

The present paper deals with the relation of rheumatoid arthritis to hepatic diseases. Rheumatoid arthritis is regarded as a general disease though the predominant articular symptoms are also accompanied by changes in other organs. Rheumatoid arthritis includes distinct dysproteinemia conditioning the positivity of the flocculation tests. This dysproteinemia is not identical with that found in hepatic diseases. The level of serum mucoproteids in case of liver damage is always lower and in rheumatoid arthritis higher. The elevated mucoprotein level makes the serum more resistant to flocculation, but his protective influence is only restricted and the flocculation cannot even be prevented by the considerably higher mucoproteid level of pronounced dysproteinemia. The specific nature of hepatic involvement could not be proved so far.

Arthritis, Rheumatoid↗
PubMed1989

Visuwell Reagin, a non-treponemal enzyme-linked immunosorbent assay for the serodiagnosis of syphilis.

A urease-based enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of reagin antibodies in serum. Visuwell Reagin (ADI Diagnostics Inc., Rexdale, Ontario, Canada) is a non-treponemal screening test for the serodiagnosis of syphilis which has the benefits of large batch testing, automatability, and objective interpretation of results. Unheated, undiluted sera are incubated in 96-well microtiter plates coated with a modified cardiolipin-lecithin-cholesterol antigen. Antibody bound to the plate is detected by an anti-human immunoglobulin G-urease conjugate. The procedure consists of three steps, with a total test time of 60 min. Visuwell Reagin ELISA was compared with the Venereal Disease Research Laboratory (VDRL) test and the reagin screening test (RST) with the following results. For ELISA versus the VDRL test, the sensitivities for untreated syphilis (n = 37) were 97.3% for both ELISA and the VDRL test, the confirmatory positive values (n = 79) were 84.8% for ELISA and 72.2% for the VDRL test, and the specificities for normal samples (n = 1,327) were 98.8% for ELISA and 99.5% for the VDRL test. For ELISA versus RST, the sensitivities for untreated syphilis (n = 57) were 94.7% for ELISA and 87.7% for RST, the confirmatory positive values (n = 26) were 96.2% for ELISA and 92.3% for RST, and the specificities for normal samples (n = 1,891) were 99.6% for ELISA and 99.3% for RST. The overall concordance values of ELISA with VDRL test and RST were 96.7 and 97.9%, respectively. The specificity of ELISA compared with that of RST may be underestimated, since confirmatory data were not available for all apparent false-positive samples. Visuwell Reagin had increased sensitivity and similar specificity compared with flocculation tests.

Antibodies↗
PubMed1986

Treponemal antibody-absorbent enzyme immunoassay for syphilis.

An enzyme immunoassay for the diagnosis of syphilis (ELISA-SY) was developed with solid-phase extracts of Treponema pallidum, specimen diluent containing Reiter treponeme absorbent, and three 30-min incubations. The ELISA-SY results were determined in comparison with a standardized positive control and reported as a percentage of strong positive control. In tests with 1,005 serum samples from a venereal disease clinic and other sources, 98.2% agreement was found with fluorescent treponemal antibody-absorption (FTA-ABS) results, and 98.3% agreement was found with T. pallidum passive hemagglutination (PHA) findings. Only 1 of 29 sera originally considered to be biologically false-positive by ELISA-SY; the latter specimen was also positive by PHA and FTA-ABS tests performed in our laboratories. Serum samples from clinically diagnosed syphilitics (16 primary-stage isolates, 7 secondary-stage isolates, and 3-latent-stage isolates) were all positive by ELISA-SY, FTA-ABS, and PHA. Serum samples from 51 newborns suspected of having syphilis on the basis of positive cardiolipin flocculation tests showed 98% agreement of ELISA-SY results with FTA-ABS and PHA findings. Sera from all 61 patients with a variety of autoimmune and other diseases known to be associated with biologically false-positive reactions for syphilis were negative by this ELISA-SY. The specificity of the ELISA procedure for T. pallidum antibody was also confirmed immunologically by blocking experiments.

Antibodies↗
PubMed1999

Preparation and in vitro characterization of HSA-mPEG nanoparticles.

Surface modified human serum albumin (HSA) nanoparticles with a size of approximately 150 nm in diameter were prepared from a PEG-HSA conjugate, methoxy-polyethylene glycol modified human serum albumin (HSA-mPEG) using a coacervation method and crosslinked with glutaraldehyde. The zeta-potential of the surface modified nanoparticles was significantly lower than that of unmodified HSA nanoparticles. The existence of a hydrated steric barrier surrounding the nanoparticles was confirmed by electrolyte and pH induced flocculation tests. The surface modified nanoparticles showed a reduced plasma protein adsorption on the particle surface compared with unmodified particles.

Animals↗
PubMed2003

Application of organic polymeric flocculants in centrifugal dewatering of oil refinery sludge.

In order to evaluate the applicability of the organic polymeric flocculants (OPF) in the treatment of oil refinery sludge, experiments were conducted to show that OPF have better performance of flocculation than inorganic flocculants. Both the anionic and cationic OPF have satisfactory flocculation efficiency in oil sludge treatment, but the latter are more cost-efficient. Among the over 20 types of flocculants tested, 2 OPF (CPAM-2 and HPAM-2) were selected as the treatment agents, based on their good treatment performances, oil-resistance and economic feasibility. It was demonstrated in the industrial-scale centrifugal dewatering experiments that the application of either CPAM-2 or HPAM-2 could achieve high treatment efficiency of the oil sludge dewatering and reduce the COD of centrifugal liquid to less than 1000 mg/L.

Accidents↗
PubMed2004

[Effect of growth phase on the flocculation of algal cells using clays].

Four different growth phases, late lag phase, middle logarithmic phase, late logarithmic phase and early senescence phase of Microcystis aeruginosa 469 were studied for their surface hydrophobicity (xylene-water system) and surface charge (Zeta potential), followed by flocculation tests with sepiolite of 0.2 g/L. The results showed that the values of hydrophobicity were 64%, 48%, 58% and 70%, and the algal removal efficiencies after 60 min were 97%, 87%, 81% and 99% respectively, indicating a good relationship between surface hydrophobicity and removal efficiency (R = 0.7-0.8), but not the surface charge. Surface hydrophobicity and removal efficiency for the algal cells of Microcystis aeruginosa both varied with growth phase in a sequence of senescence phase > lag phase > logarithmic phase.

Aluminum Silicates↗
PubMed1979

Comparison of enzyme-linked immunosorbent assay and passive hemagglutination method for quantification of antibodies to lipopolysaccharide and tetanus toxoid in rats.

In a comparative study, the enzyme-linked immunosorbent assay, using peroxidase labeled anti-rat immunoglobulin M and immunoglobulin G, and the passive hemagglutination test were applied to determine the primary and secondary antibody response to lipopolysaccharide and tetanus toxoid in rats. In the enzyme-linked immunosorbent assay, the antigens were bound to the wells of polystyrene microplates, tetanus toxoid directly, and lipopolysaccharide after complexing it with methylated bovine serum albumin. After incubation with dilutions of the rat sera, the amount of antibody bound to the solid phase was quantified by means of peroxidase-labeled anti-immunoglobulin. The specificity of the enzyme immunoassay was tested by absorption of the sera with their respective antigens. The enzyme-linked immunosorbent assay proved to be more sensitive than the hemagglutination reaction, except when titers were determined during the secondary response to tetanus toxoid. Besides its specificity and sensitivity, the enzyme-linked immunosorbent assay is a convenient method for measuring both immunoglobulin M and immunoglobulin G antibodies. At low serum dilutions of lipopolysaccharide antisera, inhibition of the reaction in the enzyme-linked immunosorbent assay occurred. This phenomenon could be prevented by heating the sera at 56 degrees C for 30 min. Lipopolysaccharide was immunogenic in rats over an extremely wide dose range (from 10 pg to 1 mg); the optimal immunogenic dose of lipopolysaccharide for young adult rats was 0.1 to 1,000 mug when administered intravenously, and that of tetanus toxoid was 5 to 10 lines of flocculation, as determined by the Ramon flocculation test.

Animals↗
PubMed2002

An epidemiologic study of trends in prevalence of rheumatoid factor seropositivity in Pima Indians: evidence of a decline due to both secular and birth-cohort influences.

OBJECTIVE: Previous population studies have suggested that both rheumatoid factor (RF) production and rheumatoid arthritis (RA) may be declining in occurrence, and both secular and birth-cohort influences have been implicated. Since Pima Indians have a very high incidence of RA and also have shown recent evidence of a decline in RA, this study evaluated the relative contributions of age, secular, and birth-cohort influences on RF seropositivity in the Pima Indian population. METHODS: RF data, as assayed by both the bentonite flocculation test (BFT) and the sheep cell agglutination test (SCAT), were available on 5,345 Pima Indians born between 1886 and 1975, who were surveyed at biennial intervals between 1966 and 1995. An age-period-cohort analysis was conducted using data on 18,295 examinations undertaken during the period of study. RESULTS: There was a decline in the proportion of positive test results for RF (titer > or = 1:32) by both BFT and SCAT, in both male and female subjects from 1966-1975 to the later decades of the study (1976-1985 and 1986-1995). Across all periods, by both assays, the crude proportion of positive titers increased with increasing age of the subjects. There was a very clear birth-cohort effect: the highest likelihood of seropositivity was in those individuals born around the end of the nineteenth century, with continuing decline in seropositivity up to the most recent birth cohort. A logistic regression analysis, adjusting for Pima heritage and sex, demonstrated a substantially greater influence of birth cohort than of calendar year on the frequency of RF positivity. CONCLUSION: In the Pima Indian population, environmental influences in early life are important predictors of the lifelong likelihood of RF positivity. This may have implications for understanding the epidemiology and etiology of RA.

Adolescent↗
PubMed1997

Preparation of surface-modified albumin nanospheres.

Surface-modified human serum albumin (HSA) nanospheres with a size of around 100 nm in diameter were prepared from poly(amidoamine)-poly(ethylene glycol) copolymer grafted human serum albumin (HSA-PAA-PEG) and poly(thioetheramido acid)-poly(ethylene glycol) copolymer grafted human serum albumin (HSA-PTAAC-PEG). The nanospheres were produced using a pH-coacervation method and cross-linked with glutaraldehyde. The cross-linking efficiency was affected by the type of albumin conjugate used. The zeta potential of the surface-modified nanospheres was significantly lower than that of unmodified particles. The existence of a hydrated steric barrier surrounding the nanospheres was confirmed by electrolyte- and pH-induced flocculation tests. The surface-modified nanospheres showed a reduced plasma protein adsorption on the particle surface compared with unmodified particles.

Adsorption↗
PubMed1994

Recognition ability and cytotoxicity of some oligosaccharidyl substituted beta-cyclodextrins.

This paper reports a chemico-enzymatic synthesis of beta-CD derivatives. The recognition properties of these derivatives were tested using flocculating yeast and isolated lectins. It was observed that the substitution of beta-cyclodextrins with galactose end arms induces the better recognition by a cell-linked galactose-specific lectin. The physicochemical effects of the beta-CD derivatives on membranes were estimated using red blood cells and the effects on the viability of yeast and human rectal tumor cells were appreciated by measuring the mitochondrial deshydrogenase activity. The substitutions of the beta-CD ring by sugar antennae decrease the negative physicochemical effects of the beta-CD, ie their hemolytic properties. However, these substitutions induce significant modifications of the biological properties of the molecules, particularly the cytotoxicity and the growth of eukaryotic cells.

Animals↗
PubMed1994

Preparation of sterically stabilized human serum albumin nanospheres using a novel Dextranox-MPEG crosslinking agent.

Human serum albumin (HSA) nanospheres with a size less than 200 nm in diameter were prepared using a modified coacervation method and crosslinking with methyl polyethylene glycol modified oxidized Dextram (Dextranox-MPEG) which created a sterically stabilizing polyethylene oxide surface layer surrounding the nanospheres. The crosslinking efficiency and the surface characteristics of glutaraldehyde and Dextranox-MPEG crosslinked HSA nanospheres were determined and compared. The zeta potential of the Dextranox-MPEG crosslinked particles was significantly lower than that of glutaraldehyde stabilized particles. The existence of a hydrated steric barrier surrounding the nanospheres was confirmed by an electrolyte and pH induced flocculation test. The Dextranox-MPEG crosslinked nanospheres showed a significantly reduced plasma protein adsorption on the particle surface compared with glutaraldehyde crosslinked nanospheres.

Chemistry, Pharmaceutical↗
PubMed1976

Serologic diagnosis of syphilis: an update.

Tests used in the serologic diagnosis of syphilis can be divided into two main groups: nontreponemal (reagin) tests and treponemal tests. The most widely used nontreponemal test is the Venereal Disease Research Laboratory (VDRL) slide test, and the standard treponemal test is the manual fluorescent treponemal antibody-absorption (FTA-ABS) test. These tests and other newer tests available for the serologic diagnosis of syphilis are reviewed, with emphasis placed on their current clinical usefulness.

Complement Fixation Tests↗
PubMed1978

Hydatid disease screening: Sanpete County, Utah, 1971-1976.

Between 1971 and 1976 approximately 20% (2,265) of the population of Sanpete County, Utah, was screened for hydatid disease (Echinococcus granulosus) by intradermal, indirect hemagglutination, and bentonite flocculation tests. Of 34 persons who had follow-up chest radiographs and radioisotope liver scans, 6 were found to have asymptomatic hepatic cysts. If a participant who had pulmonary cysts and negative screening tests were included, the prevalence of asymptomatic hydatid disease would be 3 per 1,000. During the same period, 82 (148 per 1,000) of 553 dogs successfully purged and examined had E. granulosus infections. Human cyst carriage was associated with dog ownership, particularly of infected dogs or in conjunction with sheep raising as the main livelihood. Combinations of immunodiagnostic tests were more efficacious in identifying cyst carriers than the tests used singly. Limitation of screening to high risk groups (e.g., sheep raisers with dogs) can reduce costs without reducing yield. Optimum management of the cyst carrier awaits further information on the natural history of asymptomatic hydatid disease.

Adolescent↗
PubMed1975

The differential diagnosis between intrahepatic cholestatic jaundice and viral hepatitis during pregnancy.

Clinical and laboratory findings from 15 patients with icteric viral hepatitis during pregnancy (VHP) and from 22 patients with intrahepatic cholestasis during pregnancy (CJP) were evaluated statistically in order to find out which parameters might help in order to find out which parameters might help in differentiating the two diseases. Diagnosis was established by needle liver biopsy in all cases. The following data were considered: history, physical examination, erythrocyte sedimentation rate (ESR) serum cholesterol, prothrombin time, total serum bilirubin, SGOT, SGPT, serum alkaline phosphatase, serum protein, serum flocculation tests, BSP blood clearance and serum HB Ag. Vomiting, high GOT and GPT serum levels, and serum HB Ag positivity suggest VHP diagnosis. Otherwise a severe itching with scratching lesions, high ESR, elevated total cholesterol and serum alkaline phosphatase values mainly if occurring in the later stage of pregnancy are consistent with CJP diagnosis. When clinical and laboratory data from a jaundiced pregnant female do not allow diagnosis, this can be established only on the basis of needle liver biopsy.

Alanine Transaminase↗