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Physicochemical properties of parenteral fat emulsions containing 20% triglyceride; Intralipid and Ivelip.

The paper describes an in-depth study of the parenteral fat emulsions, Intralipid 20% and Ivelip 20%. A large number of emulsion samples from separate containers and batches was sampled. The parameters measured were droplet size (both by photon correlation and laser diffraction), pH and zeta potential. These parameters were re-measured after the emulsions were subjected to a number of accelerated stability tests (freeze-thaw cycling, autoclaving and shaking). The results demonstrate that although the Intralipid is stable, it can show some variability between separate batches. The stability of Ivelip is high, and the variability between separate batches is extremely low.

Calcium↗

Parallel evaluation of serological tests applied in african trypanosomiasis: a WHO collaborative study.

Previously, the most commonly used serological tests for the indirect diagnosis of African trypanosomiasis were the indirect fluorescent antibody test, immunodiffusion test, and the determination of IgM levels in serum and cerebrospinal fluid. Recently, the capillary passive haemagglutination test and the enzyme-linked immunosorbent assay (ELISA) have been used in diagnosing trypanosomiasis. However, a parallel evaluation was needed to indicate the comparative diagnostic value of these various serological tests. A double-blind study conducted by WHO with the collaboration of three European and four African laboratories using well-documented serum samples provides a reasonable basis for determining in parallel the sensitivities of the various techniques.

Clinical Trials as Topic↗

Comparison of maternal and newborn serologic tests for syphilis.

OBJECTIVE: To compare the cord blood, newborn serum, and maternal serum for the diagnosis of congenital syphilis. DESIGN: Retrospective chart review. SETTING: Kings County Hospital Center, Brooklyn, NY. PATIENTS: Three hundred forty-eight mother-newborn pairs with positive syphilis serology. MEASUREMENTS AND RESULTS: One hundred fifteen newborns (33%) had rapid plasma reagin tests of cord blood that were nonreactive. Their mothers had positive serologic findings. There were 10% false-positive cord blood samples (cord blood rapid plasma reagin tests reactive, newborn serum rapid plasma reagin tests nonreactive) and 5% false-negative cord blood samples (cord rapid plasma reagin tests nonreactive, newborn serum rapid plasma reagin tests reactive). Thirty-three newborns had congenital syphilis. Seven newborns had cord titers fourfold higher than their mothers'; only four of these newborns had congenital syphilis. Maternal serology is superior to cord blood analysis for identifying newborns at risk of congenital syphilis.

False Negative Reactions↗

[Diagnostic valve of ELISA-IgG for trichinosis using Melcher's antigen].

An enzyme-linked immunosorbent assay (ELISA) for trichinosis using a Melcher's antigen was developed for the detection of IgG antibodies in 41 serum samples from patients confirmed or suspected to have trichinosis by strong clinical and epidemiological evidences. ELISA- IgG was compared with a precipitin test (PT), a bentonite floculation test (BFT) and an indirect hemagglutination test (IHAT). The cut-off value was determined using serum samples from 67 apparently healthy persons employing two serum dilutions (1:100 and 1:500) with three standard deviations (SD). The sensitivity of ELISA- IgG was 97.6% and 95.2% using serum dilutions of 1:100 and 1:500 respectively, whereas the values for the other tests were: PT (92.7%), BFT (63.4%) and IHAT(85.4%). According to MacNemar test, ELISA-IgG did not present statistical significance (p > 0.05) compared with PT and IHAT, whereas all of them were different compared with BHT (p > 0.01). In order to find out the specificity of ELISA-IgG, additional 124 serum samples from individuals with other parasitoses, such as cysticercosis (31), fascioliasis (17), hydatidosis (51) and toxocariasis (25) were also tested. ELISA-IgG presented a specificity of 99.5% with both serum dilutions. The positive predictive values were 97.6 and 97.5%, whereas the negative one were 99.5 and 99.0% for 1:100 and 1:500 serum dilutions respectively. The use of ELISA-IgG and Melcher's antigen in the diagnosis of human trichinosis is discussed.

Adult↗

Double diffusion in gel reactions with antigens insoluble in aqueous media.

Ethanol-soluble, but saline-insoluble antigens were prepared as saline suspensions and studied in double diffusion reactions in a soft agarose gel. Positive reactions were observed with syphilis and SLE sera tested against the Kahn antigen as well as against commercial cardiolipin reagents. Also, ethanol-soluble brain antigen was studied for organ-specific reactions with rabbit immune sera. It was shown that double diffusion in gel can be employed as an analytical procedure for studies on reactions of saline suspensions of ethanol-soluble antigens.

Animals↗

Anticardiolipin antibodies in eclampsia.

Twenty patients with eclampsia were studied for the presence of anticardiolipin antibodies by the standard microflocculation test (quantitative) used in the VDRL. Four out of 20 patients (20%) were positive for anticardiolipin antibodies. Anticardiolipin antibodies which are antiphospholipid antibodies by decreasing the prostacyclin production may damage the vascular endothelium and cause thrombosis in the vessels. Hence, the presence of anticardiolipin antibody in eclampsia may have association with antiphospholipid antibody syndrome described by Harris et al. (Lancet ii: 1211, 1983) and its central nervous system sequelae.

Adult↗

Relationship of phospholipid chemistry to serological reactivity in the Venereal Disease Research Laboratory slide test antigen.

A total of 13 egg lecithins, 12 beef heart lecithins, and 15 beef heart cardiolipins were assayed for the ability to function in the Venereal Disease Research Laboratory microflocculation test, as well as for purity, fatty acid composition, free amines, metals, and products of oxidation. We found that the presence of peroxides and oxidation-related ultraviolet-absorbing chromophores showed a close inverse relationship to acceptable serological activity. The degree of purity of the lipids had only a slight influence on serological activity, whereas fatty acid composition, saturation, and configuration had none at all. We did not detect contaminating iron, copper, cobalt, nickel, or free amines in these lipids. We discuss the implications of our findings for improving the chemical standards for these lipids.

Antigens↗

Pathogenesis of acute avian malaria. II. Anemia mediated by a cold-active autohemagglutinin from the blood of chickens with acute Plasmodium gallinaceum infection.

A cold-active hemagglutinin for trypsinized human type "O" erythrocytes (CAH) from blood of chickens with acute Plasmodium gallinaceum malaria was found to be associated with 19 S and 7 S globulin fractions of malarious chicken blood, but cleavage with 2-mercaptoethanol indicated that it was primarily of the IgM class of antibody. In serologic tests CAH reacted with trypsinized erythrocytes, and anti-chicken globulin. It did not react with other of the antigens or antibodies detected in the blood of malarious chickens. When the absorbed and eluted CAH was injected into normal chickens it produced an anaphylactic-like shock and caused a 25% reduction in red blood cell counts within 48 hours. Plasma samples collected during this interval showed signs of hemolysis. Reactions of blood cells from the recipient birds with fluorescein conjugated anti-chicken globulin indicated that CAH reacted with erythrocytes. The absence of fluorescent activity 3 days after injection suggested that these erythrocytes had been removed from the circulation. When normal chickens were injected with trypsinized autologous blood cells, CAH was detected within 3 days. The agglutination test again was active at temperatures below 22 degrees C and was negative when tested at 37 degrees C. In these birds the appearance of CAH was accompanied by reductions in red blood cell counts and by hemolysis. The results of these experiments suggest that CAH was not stimulated by plasmodial parasite antigen, but rather by autoantigens, which appear to be common to heterologous animal species, and which were in some manner expressed by the presence of the intracellular parasites, or by trypsin treatment. The experiments further suggest that this autohemagglutinin was partially causal of malarial anemia. The presence of other anemia factor(s) was indicated by anemia following injection of plasma that had been absorbed free of CAH.

Agglutinins↗

Double diffusion in gel tests with Paul-Bunnell antibodies of infectious mononucleosis sera.

Double diffusion tests in gel were employed for studies of reactions between infectious mononucleosis sera and extracts of bovine, sheep and equine erythrocyte stromata. The extracts were obtained by ultrasonication of stromata prepared from trypsin-digested erythrocytes. The reaction with bovine stroma extract was composed, in many instances, of two lines. A single line was observed in reactions with sheep and equine stroma extracts. This line merged into a reaction of partial or complete identy with one of the lines formed with bovine stroma extract. Evidence was obtained that some infectioous mononucleosis sera may contain heterophile (Paul-Bunnell) antibodies belonging to IgG class in addition to those of IgM nature.

Animals↗

Serological evidence for syphilis in different population groups in Rwanda.

The prevalence of serological syphilis, based on qualitative VDRL slide test was studied in different population groups in Rwanda. A positive VDRL was found in 0.7% of female students of a social school, in 2.2% of male and female premarital consultants, in 3.2% of prenatal consultants, in 6.5% of soldiers, and in 27.9% of prostitutes. As the first groups were not exposed to venereal disease, VDRL reactivity due to biological false positive reaction or to yaws antecedents is estimated at 0.5 to 2%. Accordingly, VDRL reactivity due to syphilis is estimated at 1 to 2% in prenatal consultants, 5 to 6% in soldiers and 25 to 26% in prostitutes. It is concluded that syphilis is not yet an important public health problem except in certain promiscuous population groups in towns, as soldiers, migrant workers and prostitutes.

Adolescent↗

The potential role of custody facilities in controlling sexually transmitted diseases.

BACKGROUND: The National Commission on Correctional Health Care recommends that medical screening, including tests for syphilis and other sexually transmitted diseases, be performed by the 14th day after initial booking procedures. Because the average length of stay in detention is usually less than 14 days, most detainees are not screened or treated for asymptomatic communicable diseases. METHODS: In order to determine the incidence and prevalence of syphilis among those booked through a large county jail, a rapid screening procedure to test newly incarcerated inmates and treat those infected was implemented over a 3-week period. RESULTS: Among 6309 detainees eligible for testing during the 3-week period of the study, 129 (2%) were diagnosed with syphilis. During the preceding month when only those reporting symptoms or high-risk behaviors were screened, 20 cases were diagnosed. The sensitivity and predictive value of self-reported risk factors for syphilis infection were low. Among the first 110 diagnosed cases, 17 (15.5%) were released within 3 days and 86 (78%) were released within 6 days. CONCLUSIONS: If screening and treatment for syphilis are delayed until the 14th day after booking, the majority of infected inmates will be released prior to evaluation and treatment. Rapid screening and treatment for selected sexually transmitted diseases are likely to be an effective public health measure when implemented in custody settings.

Adolescent↗