Immunotoxic Effects of MPT-IP Containing 60% Methylparathion in Mice

1992 ◽  
Vol 11 (1) ◽  
pp. 11-16 ◽  
Author(s):  
L. Institóris ◽  
Olga Siroki ◽  
S. Tóth ◽  
I. Dési
Keyword(s):  
Antibody Titre ◽  
Time Course ◽  
Serum Antibody ◽  
Industrial Product ◽  
Experimental Conditions ◽  
Small Doses ◽  
Serum Antibody Titre

The effects of a single large and repeated small doses of MPT-IP (the industrial product used to produce Wofatox EC 50) containing 60% methylparathion, on the humoral and cellular immunoreactivity of CFLP mice were investigated. Administration of a single LD50/2 dose 3 d prior to immunization caused a 40% increase in the number of splenic PFC on the 5th day but no significant increase in serum antibody titre on the 7th day after immunization. Treatment for 4 weeks with an LD50/40 dose resulted in a 100% increase in splenic PFC, also not associated with a change in serum antibody titre. Under the same conditions and LD50/20 dose had no effect on these parameters. Neither the single large nor the repeated small doses had any effect on the intensity or time course of a DTH reaction. The results show that MPT-IP has an immunotoxic potential in mice under certain experimental conditions.

scholarly journals A graded-dose study of inactivated, surface antigen influenza B vaccine in volunteers: reactogenicity, antibody response and protection to challenge virus infection

1983 ◽  
Vol 90 (1) ◽  
pp. 107-115 ◽  
Author(s):  
A. Goodeve ◽  
C. W. Potter ◽  
A. Clark ◽  
R. Jennings ◽  
G. C. Schild ◽  
...  
Keyword(s):  
Hong Kong ◽  
Virus Infection ◽  
Antibody Response ◽  
Antibody Titre ◽  
Serum Antibody ◽  
Influenza B ◽  
Challenge Virus ◽  
Antibody Titres ◽  
Dose Study ◽  
Serum Antibody Titre

SUMMARYOne hundred and nineteen volunteers were divided into five groups, and each volunteer inoculated subcutaneously with an aqueous subunit B/Hong Kong/73 vaccine containing 40, 20, 10, or 5 μg of HA or saline alone in a 0·5 ml volume. The incidence of reactions was recorded 24 h after inoculation. One month following immunization the serum HI antibody to B/Hong Kong/73 virus was measured; each volunteer was inoculated intranasally with live, attenuated influenza B (RB77) virus; and the incidence of infection by the challenge virus was determined by HI antibody response.The results showed that the incidence of reactions to all doses of vaccine were relatively low, the severity mild, and the duration short. However, the incidence of reactions was highest for those given 40 μg HA and least for those given 5 μg HA. The serum HI antibody responses to vaccine showed a dose-response relationship. For volunteers given 40 μg HA, 22 (96%) showed a fourfold rise in antibody titre and all volunteers had antibody titres of > 40 following immunization: for volunteers given 5 μg HA the g.m.t. increased from 16·6 to 86·1; and for those given 10 and 20 μg HA the response was intermediate. Following challenge, the lowest incidence of infection was seen in volunteers given the highest dose of vaccine. However, all doses of vaccine induced some protection against challenge virus infection, and the incidence of infection was directly related to the serum antibody titre at the time of challenge. The 50% protection titre of serum HI antibody was estimated as 15 to 20.

Bullous pemphigoid: serum antibody titre and antigen specificity

1995 ◽  
Vol 4 (6) ◽  
pp. 372-376 ◽  
Author(s):  
Hendri H. Pas ◽  
Marcelus C. J. M. Jong ◽  
Marcel E Jonkman ◽  
Klaas Heeres ◽  
Ida J. Slijper-Pal ◽  
...  
Keyword(s):  
Bullous Pemphigoid ◽  
Antibody Titre ◽  
Serum Antibody ◽  
Antigen Specificity ◽  
Serum Antibody Titre

Immunological Studies on Experimental Infection of Pigs with Ascaris suum Goeze, 1782. V.—The Antibody Response to the Oral Administration of Third- and Fourth-Stage Larvae

1964 ◽  
Vol 38 (1-2) ◽  
pp. 159-170 ◽  
Author(s):  
L. F. Taffs
Keyword(s):  
Oral Administration ◽  
Antibody Titre ◽  
Serum Antibody ◽  
Antibody Concentration ◽  
Fourth Stage ◽  
Sharp Rise ◽  
Maximum Serum ◽  
Saline Extract ◽  
Faecal Egg Count ◽  
Serum Antibody Titre

Following the oral administration of third- and fourth-stage A. suum larvae, which had previously completed nine or ten days somatic migration in guineapigs, rabbits or a pig, six out of eight pigs showed a rise of serum antibody titre, as measured by the conglutinating complement absorption test using a saline extract of Ascaris worm as antigen. Four of these pigs had negative titres before infection, and in these animals antibodies were first detected between the 14th and 20th days. Maximum serum antibody concentration was reached between the 14th and 34th days of infection, and antibodies were detected for at least as long as 68 days.Larvae were recovered from the faeces on the 23rd and 29th days of infection, and in two pigs out of eight the larvae reached maturity, eggs first being seen in the faeces on the 42nd day.The results suggest that (1) Ascaris larvae, on their return to the intestine, release antigenic substances which are then absorbed by the gut wall to stimulate the production of antibodies; (2) the secondary antibody rise, which occurs about the sixth or seventh week of an infection with Ascaris eggs, is due to the absorption of this larval antigen; and (3) the moulting process (fourth moult) is not only an important stage for stimulating this further antibody production, but is also the time when maturing larvae are affected by the immune mechanisms of the host.On reinfection with Ascaris eggs the phenomenon of “self-cure” was noticed. A fall in the faecal egg count, which became negative on the 21st day, was accompanied by a sharp rise in antibody titre. An increase in the number of infertile eggs in the faeces, rising from 11% on the day of reinfection to 100% on the 14th day, was also observed.

scholarly journals The conglutination phenomenon. III. The conglutinating complement absorption test in experimental glanders

1947 ◽  
Vol 45 (4) ◽  
pp. 497-503 ◽  
Author(s):  
N. H. Hole ◽  
R. R. A. Coombs
Keyword(s):  
Oral Administration ◽  
Antibody Titre ◽  
Complement Fixation Test ◽  
Complement Fixation ◽  
Serum Antibody ◽  
Fixation Test ◽  
Absorption Test ◽  
Serum Antibodies ◽  
Serum Antibody Titre ◽  
Detectable Serum

1. Observations on the sera of ponies, taken at frequent intervals for 321 days after oral administration of P. mallei, are described.2. It was found that the conglutinating complement absorption test was more sensitive than the haemolytic complement fixation test as a means of diagnosis. It detected the antibodies earlier in the course of the disease and demonstrated their presence over a longer period of time.3. The possibility of another practical use of this reaction as an adjunct to the allergic test is considered. Ten days after an intradermo-palpebral test a pony, which had been previously sensitized and whose serum antibody titre at that time was below 10, developed a serum titre of over 160 as demonstrated by the conglutinating complement absorption test. Under similar circumstances 11 unsensitized ponies developed no detectable serum antibodies.

Studies on Tyzzer's Disease: Acquired Immunity Against Infection and Activation of Infection by Immunosuppressive Treatment

1979 ◽  
Vol 13 (2) ◽  
pp. 143-148 ◽  
Author(s):  
A. Schaich Fries
Keyword(s):  
Antibody Titre ◽  
Persistent Infection ◽  
Immunosuppressive Treatment ◽  
Acquired Resistance ◽  
Serum Antibody ◽  
Challenge Infection ◽  
Acquired Immunity ◽  
Serum Antibody Titre ◽  
Resistance To Infection ◽  
Immunofluorescence Antibody

Summary The correlation between serum antibody titre and resistance to challenge infection with Bacillus piliformis was studied in naturally infected mice, in experimentally infected but recovered mice, and in mice treated with antigen prepared from infected livers. Irrespective of the way in which the antibodies were acquired resistance to infection was found to be related to the immunofluorescence antibody titre found. Experimentally infected but recovered mice, as well as rats with persistent antibodies to Bacillus piliformis, were given prednisolone in order to activate a possible persistent infection. Bacillus piliformis was detected in the rats, but not in the mice.

A Simple Method for Estimation of Lipoxygenase and Cyclo-Oxygenase Pathways in Human Platelets - the Use of Thiobarbituric Acid Reaction

1980 ◽  
Vol 44 (02) ◽  
pp. 111-114 ◽  
Author(s):  
Hiroshi Takayama ◽  
Minoru Okuma ◽  
Haruto Uchino
Keyword(s):  
Time Course ◽  
Normal Values ◽  
Human Platelet ◽  
Thiobarbituric Acid ◽  
Human Platelets ◽  
Optimal Conditions ◽  
Experimental Conditions ◽  
Simple Method ◽  
Acid Reaction ◽  
Optimal Ph

SummaryTo develop a simple method for estimation of platelet lipoxygenase (PLO) and cyclo-oxygenase (PCO) pathways, the arachidonic acid (AA) metabolism of human platelet was investigated under various experimental conditions by the use of the thiobarbituric acid (TBA) reaction and a radioisotope technique. A TBA-reactive substance different from malondialdehyde (MDA) via PCO pathway was detected and shown to be derived from the PLO pathway. Since the optimal pH and time course of its formation were different from those of MDA formation via PCO pathway, PLO and PCO pathways were estimated by quantitating the TBA-reactive substances produced by the incubation of AA either with aspirin-treated platelets or with untreated ones, respectively, each under optimal conditions. Normal values expressed in terms of nmol MDA/108 platelets were 1.17±0.34 (M±SD, n = 31) and 0.79±0.15 (n = 31) for PLO and PCO pathways, respectively.

scholarly journals Role of Mammalian Auditory Cortex in the Perception of Elementary Sound Properties

2001 ◽  
Vol 85 (6) ◽  
pp. 2350-2358 ◽  
Author(s):  
Sanjiv K. Talwar ◽  
Pawel G. Musial ◽  
George L. Gerstein
Keyword(s):  
Auditory Cortex ◽  
Time Course ◽  
Auditory Evoked Potentials ◽  
Mammalian Species ◽  
Sound Intensity ◽  
Primary Auditory Cortex ◽  
Normal Hearing ◽  
Auditory Task ◽  
Experimental Conditions

Studies in several mammalian species have demonstrated that bilateral ablations of the auditory cortex have little effect on simple sound intensity and frequency-based behaviors. In the rat, for example, early experiments have shown that auditory ablations result in virtually no effect on the rat's ability to either detect tones or discriminate frequencies. Such lesion experiments, however, typically examine an animal's performance some time after recovery from ablation surgery. As such, they demonstrate that the cortex is not essential for simple auditory behaviors in the long run. Our study further explores the role of cortex in basic auditory perception by examining whether the cortex is normally involved in these behaviors. In these experiments we reversibly inactivated the rat primary auditory cortex (AI) using the GABA agonist muscimol, while the animals performed a simple auditory task. At the same time we monitored the rat's auditory activity by recording auditory evoked potentials (AEP) from the cortical surface. In contrast to lesion studies, the rapid time course of these experimental conditions preclude reorganization of the auditory system that might otherwise compensate for the loss of cortical processing. Soon after bilateral muscimol application to their AI region, our rats exhibited an acute and profound inability to detect tones. After a few hours this state was followed by a gradual recovery of normal hearing, first of tone detection and, much later, of the ability to discriminate frequencies. Surface muscimol application, at the same time, drastically altered the normal rat AEP. Some of the normal AEP components vanished nearly instantaneously to unveil an underlying waveform, whose size was related to the severity of accompanying behavioral deficits. These results strongly suggest that the cortex is directly involved in basic acoustic processing. Along with observations from accompanying multiunit experiments that related the AEP to AI neuronal activity, our results suggest that a critical amount of activity in the auditory cortex is necessary for normal hearing. It is likely that the involvement of the cortex in simple auditory perceptions has hitherto not been clearly understood because of underlying recovery processes that, in the long-term, safeguard fundamental auditory abilities after cortical injury.

scholarly journals Comparative biofilm assays using Enterococcus faecalis OG1RF identify new determinants of biofilm formation

2021 ◽  
Author(s):  
Julia L. E. Willett ◽  
Jennifer L. Dale ◽  
Lucy M. Kwiatkowski ◽  
Jennifer L. Powers ◽  
Michelle L. Korir ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Growth Medium ◽  
Biofilm Formation ◽  
Time Course ◽  
Opportunistic Pathogen ◽  
Genetic Determinants ◽  
Experimental Conditions ◽  
Biofilm Reactors ◽  
Biofilm Architecture ◽  
Biofilm Development

AbstractEnterococcus faecalis is a common commensal organism and a prolific nosocomial pathogen that causes biofilm-associated infections. Numerous E. faecalis OG1RF genes required for biofilm formation have been identified, but few studies have compared genetic determinants of biofilm formation and biofilm morphology across multiple conditions. Here, we cultured transposon (Tn) libraries in CDC biofilm reactors in two different media and used Tn sequencing (TnSeq) to identify core and accessory biofilm determinants, including many genes that are poorly characterized or annotated as hypothetical. Multiple secondary assays (96-well plates, submerged Aclar, and MultiRep biofilm reactors) were used to validate phenotypes of new biofilm determinants. We quantified biofilm cells and used fluorescence microscopy to visualize biofilms formed by 6 Tn mutants identified using TnSeq and found that disrupting these genes (OG1RF_10350, prsA, tig, OG1RF_10576, OG1RF_11288, and OG1RF_11456) leads to significant time- and medium-dependent changes in biofilm architecture. Structural predictions revealed potential roles in cell wall homeostasis for OG1RF_10350 and OG1RF_11288 and signaling for OG1RF_11456. Additionally, we identified growth medium-specific hallmarks of OG1RF biofilm morphology. This study demonstrates how E. faecalis biofilm architecture is modulated by growth medium and experimental conditions, and identifies multiple new genetic determinants of biofilm formation.ImportanceE. faecalis is an opportunistic pathogen and a leading cause of hospital-acquired infections, in part due to its ability to form biofilms. A complete understanding of the genes required for E. faecalis biofilm formation as well as specific features of biofilm morphology related to nutrient availability and growth conditions is crucial for understanding how E. faecalis biofilm-associated infections develop and resist treatment in patients. We employed a comprehensive approach to analysis of biofilm determinants by combining TnSeq primary screens with secondary phenotypic validation using diverse biofilm assays. This enabled identification of numerous core (important under many conditions) and accessory (important under specific conditions) biofilm determinants in E. faecalis OG1RF. We found multiple genes whose disruption results in drastic changes to OG1RF biofilm morphology. These results expand our understanding of the genetic requirements for biofilm formation in E. faecalis that affect the time course of biofilm development as well as the response to specific nutritional conditions.

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