scholarly journals Microcapsules on Streptococcus mutans Serotypes by Electron Microscopy

1977 ◽  
Vol 56 (2) ◽  
pp. 166-176 ◽  
Author(s):  
Ella M. Grenier ◽  
R.H. Gray ◽  
W.J. Loesche ◽  
W.C. Eveland
Keyword(s):  
Electron Microscopy ◽  
Streptococcus Mutans ◽  
Fluorescent Antibody ◽  
Immune Serum ◽  
Rabbit Serum ◽  
Indirect Fluorescent Antibody ◽  
Bacterial Strains ◽  
Capsular Material

Extracellular microcapsules have been demonstrated on cells of most serotypes of Streptococcus mutans by electron microscopy, using bacterial strains of the various serotypes and peroxidase labeled or unlabeled immune serum. A correlation was noted between the amount of capsular substance on the strains of S mutans examined and degree of antigenicity as expressed by the indirect fluorescent antibody (FA) title. A serotype d strain was shown to lose both antigenicity as determined by the FA reaction and capsular material as seen by electron microscopy with repeated in vitro passage. When 10% unheated rabbit serum was added to the medium, antigenicity and capsular material were restored.

scholarly journals The anti-adherence effect of Lippia sidoides Cham: extract against microorganisms of dental biofilm

2013 ◽  
Vol 15 (1) ◽  
pp. 41-46 ◽  
Author(s):  
A.C.L. Albuquerque ◽  
M.S.V. Pereira ◽  
D.F. Silva ◽  
L.F. Pereira ◽  
F.A.C. Viana ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
Folk Medicine ◽  
Tooth Surface ◽  
Bacterial Strains ◽  
Lippia Sidoides ◽  
Dental Biofilm ◽  
Scientific Exploration ◽  
Infectious Origin ◽  
In Vitro Simulation

Most illnesses affecting the oral cavity are proven to have infectious origin. Several categories of chemical agents have been used in the chemical control of dental biofilm through strategies that aim at reducing bacterial adhesion and inhibiting the growth and the proliferation of microorganisms on the tooth surface. The use of plants in folk medicine and in Dentistry, as well as the spread of successful cases, has led to scientific exploration, resulting in chemical-pharmacological knowledge of thousands of plants. The present study aimed to evaluate the anti-adherence activity of Lippia sidoides Cham., comparing the results with those of 0.12% chlorhexidine by means of an in vitro simulation of dental biofilm. The studied bacterial strains were Streptococcus mutans, Streptococcus sanguinis and Lactobacillus casei, main responsible for the biofilm adherence. The studied extract was effective in inhibiting the adherence of Streptococcus mutans up to a concentration of 1:16, compared to Chlorhexidine. Lippia sidoides Cham extract showed anti-adherence effect on the major microorganisms responsible for dental biofilm consolidation.

Dipetalonema viteae: ultrastructural study on the in vitro interaction between rat macrophages and microfilariae in the presence of IgE antibody

Parasitology ◽  
1981 ◽  
Vol 82 (1) ◽  
pp. 55-62 ◽  
Author(s):  
M. A. Ouaissi ◽  
A. Haque ◽  
A. Capron
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ultrastructural Study ◽  
Peritoneal Macrophages ◽  
Immune Serum ◽  
Sequence Of Events ◽  
Transmission Electron ◽  
Dipetalonema Viteae ◽  
In Vitro Interaction

SUMMARYThe in vitro interaction between rat peritoneal macrophages and Dipetalonema viteae microfilariae in the presence of amicrofilaraemic rat immune serum was studied by transmission electron microscopy. The probable sequence of events leading to the killing of D. viteae microfilaria by macrophages is as follows. (a) Rat peritoneal macrophages in the presence of amicrofilaraemic rat immune serum adhere to the parasite surface, (b) the macrophages extend their pseudopodia around the parasite, (c) the ‘lysosome-like’ granules discharge their contents on to the parasite surface, (d) the lytic activity of these products begins at the parasite surface and (e) subsequent breaking of the microfilarial cuticle occurs, exposing the parasite intracellular material.

Synthesis, characterization and application of green seaweed mediated silver nanoparticles (AgNPs) as antibacterial agents for water disinfection

2018 ◽  
Vol 78 (1) ◽  
pp. 235-246 ◽  
Author(s):  
D. Dixit ◽  
D. Gangadharan ◽  
K. M. Popat ◽  
C. R. K. Reddy ◽  
M. Trivedi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Antibacterial Agents ◽  
Bacterial Count ◽  
Water Disinfection ◽  
Bacterial Strains ◽  
Vis Spectroscopy ◽  
Green Seaweed

Abstract A simple and eco-friendly method for the synthesis of hybrid bead silver nanoparticles (AgNPs) employing the aqueous extract derived from natural and renewable source namely tropical benthic green seaweed Ulva flexuosa was developed. This route involves the reduction of Ag+ ions anchored onto macro porous methacrylic acid copolymer beads to AgNPs for employing them as antibacterial agents for in vitro water disinfection. The seaweed extract itself acts as a reducing and stabilizing agent and requires no additional surfactant or capping agent for forming the AgNPs. The nanoparticles were analyzed using high-resolution transmission electron microscopy, UV–Vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and inductively coupled plasma optical emission spectroscopy. The study elucidates that such biologically synthesized AgNPs exhibit potential antibacterial activity against two Gram positive (Bacillus subtilis, Staphylococcus aureus) and two Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacterial strains tested. The bacterial count in treated water was reduced to zero for all the strains. Atomic force microscopy was performed to confirm the pre- and post-state of the bacteria with reference to their treatment with AgNPs. Attributes like facile environment-friendly procedure, stability and high antibacterial potency propel the consideration of these AgNPs as promising antibacterial entities.

The source, release and specificity of proteolytic enzyme activity produced by Anisakis simplex larvae (Nematoda: Ascaridida) in vitro

1984 ◽  
Vol 58 (3) ◽  
pp. 175-185 ◽  
Author(s):  
Bernard E. Matthews
Keyword(s):  
Enzyme Activity ◽  
Proteolytic Enzyme ◽  
Fluorescent Antibody ◽  
Anisakis Simplex ◽  
Excretory System ◽  
Indirect Fluorescent Antibody ◽  
Continuous Synthesis ◽  
Proteolytic Enzyme Activity ◽  
Third Stage

ABSTRACTIndirect fluorescent antibody techniques and incubation of sectioned and ligatured larvae have been used to locate the source of azocoll-positivc secretions within the oesophagcal glands of third-stage Anisakis simplex larvae. The “excretory” system, previously suggested as a source of invasive enzymes, docs not seem to be involved. The proteolytic enzyme has trypsin-like properties and evidence is presented for its continuous synthesis during in vitro storage.

Antibacterial Activity In Vitro of the Developed Glass Ionomer Cements

2011 ◽  
Vol 493-494 ◽  
pp. 375-380
Author(s):  
Joanna Karaś ◽  
Andrzej Roman Olszyna ◽  
Ewa Zaczyńska ◽  
Anna Czarny ◽  
Krzysztof Szamałek
Keyword(s):  
Antibacterial Activity ◽  
Streptococcus Mutans ◽  
Initial Period ◽  
Control Culture ◽  
Fluoride Release ◽  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
Bacterial Strains ◽  
Daily Amount

The purpose of the study was to identify the influence of the amount of fluoride release from glass ionomer cements on survival of bacterial strains responsible for the development of secondary caries. All developed cements had an antibacterial impact on the strains used in the study. The study demonstrated that the cements exhibit greater antibacterial activity againstStreptococcus mutansthanStreptococcus sanguinis. The numbers of bacteria count in cultures on the developed cements were approximately 10 times lower compared to the control culture after 24 h, 48 h, 72 h and 7 days. The developed cements had initially (1-2 days) greater antibacterial impact against the strains used in the study,which corresponds to the greatest daily amount of fluoride released from the cements. Following the initial period, the antibacterial activity of all the cements remained roughly at the same level.

scholarly journals STUDIES ON PNEUMOCOCCUS GROWTH INHIBITION

1924 ◽  
Vol 40 (4) ◽  
pp. 467-485 ◽  
Author(s):  
Oswald H. Robertson ◽  
Richard H. P. Sia
Keyword(s):  
Growth Inhibition ◽  
Protective Action ◽  
Immune Serum ◽  
Rabbit Serum ◽  
In Vitro Test ◽  
High Dilution ◽  
Protective Properties ◽  
Growth Inhibitory ◽  
Vitro Test

Using the method described in an earlier publication for testing the growth-inhibitory and bactericidal activity of serum-leucocyte mixtures for the pneumococcus, a study has been made of the action of antipneumococcus serum added to the serum and leucocytes of the rabbit, which alone lack the power to inhibit pneumococcus growth. It was found that the additiori of relatively small quantities of immune serum to a mixture of rabbit serum and washed rabbit leucocytes conferred on this mixture marked growth-inhibitory and pneumococcidal powers. The effect of the immune serum was found to be quantitative in nature. Beyond a certain point progressive dilution of the serum resulted in a corresponding decrease in the degree of growth inhibition, but this property of the immune serum did not disappear until a high dilution was reached. The leucocytes were also found to exert their effect quantitatively. Within certain limits the number of pneurnococci killed was dependent on the quantity of them present. Tests comparing the action of immune serum in the rabbit serum-leucocyte tubes with their protective action in mice showed a close parallelism between these two effects; that is to say, an immune serum showing marked protective properties for mice was likewise effective in high dilution in the in vitro test, and vice versa.

scholarly journals THE EFFECT OF ANTIBODY ON INTRACELLULAR PARASITISM OF SALMONELLA TYPHIMURIUM IN MONONUCLEAR PHAGOCYTES IN VITRO

1959 ◽  
Vol 110 (5) ◽  
pp. 715-730 ◽  
Author(s):  
Justus Gelzer ◽  
Emanuel Suter
Keyword(s):  
Salmonella Typhimurium ◽  
Gamma Globulin ◽  
Fluorescent Antibody ◽  
Immune Serum ◽  
Mononuclear Phagocytes ◽  
Fluorescent Antibody Technique ◽  
Antibody Technique ◽  
Long Time ◽  
Infected Cells

The effect of antibody on the fate of Salmonella typhimurium within mononuclear phagocytes (MN) of rabbits was studied in vitro. Monocytes and bacteria were incubated either in absence or presence of antibody. After 45 minutes during which phagocytosis occurred infected cells were washed to remove extracellular bacilli and free antibody. The cells were then reincubated in a medium without addition of antibody, and the interaction between the MN and bacteria was followed, correlating bacterial viability and the morphology of the mixture. The following results were obtained. The anti-Salmonella antibody was not bactericidal even in presence of complement and did not enhance phagocytosis. Regardless of whether antibody was present or absent during phagocytosis, the bacteria appeared to multiply within the cells. When no antibody was present during phagocytosis the infected cells were severely damaged within a few hours of incubation, and extensive extracellular multiplication was dominating. When antibody was present during phagocytosis MN packed with bacteria persisted for a long time. Little or no extracellular growth occurred. It was possible to demonstrate the presence of the antibody within the infected MN, using the fluorescent antibody technique. The antibody appeared as a coat around the bacteria. Antibody entered the cells only during phagocytosis, presumably attached to the bacteria. The active factor of the immune serum was found in the gamma globulin fraction and reacted specifically with the somatic antigen of Salmonella typhimurium. The antiflagellar portion of the antiserum was not involved in the phenomenon described. It is concluded that this antibody protects monocytes against the effect of intracellularly located Salmonella.

scholarly journals FURTHER OBSERVATIONS ON THE PHENOMENA ENCOUNTERED IN ATTEMPTING TO TRANSMIT VARICELLA TO RABBITS

1924 ◽  
Vol 39 (6) ◽  
pp. 777-802 ◽  
Author(s):  
Thomas M. Rivers ◽  
William S. Tillett
Keyword(s):  
Whole Blood ◽  
Vaccine Virus ◽  
Immune Serum ◽  
Intradermal Injection ◽  
Passive Immunity ◽  
Rabbit Serum ◽  
Intravenous Injections ◽  
Vesicle Fluid ◽  
Immune Rabbit

1. The intradermal method of inoculating Virus III, a hitherto unknown filterable virus producing lesions in rabbits, gives more reliable results than those obtained by smearing the virus on the scarified skin. 2. Virus III, heated 10 minutes at 55°C., will not produce visible reactions in the skin of rabbits. 3. Virus III passes through Berkefeld N and V filters. 4. The data obtained so far indicate that the best method of preserving Virus III in an active state is to filter the testicular emulsions containing the virus, add glycerol to the filtrate up to 40 per cent of the total volume, seal with vaseline, and store on ice. 5. Viable Virus III produces a definite immunity in rabbits which persists for at least 6 months. The immunity follows intradermal, intratesticular, intravenous, intracerebral, or intranasal inoculations of the virus. 6. A single intradermal injection of Virus III, which has been killed by heat, will not produce a demonstrable immunity in rabbits. 7. No passive immunity to Virus III could be demonstrated in rabbits which had received intravenous injections of 5 to 10 cc. of immune rabbit serum 24 hours previously. 8. Immune rabbit serum neutralizes Virus III either in vitro, or locally in a rabbit's skin when the immune serum and the virus are injected into the same part of the skin at or about the same time. 9. Three strains of the virus under investigation are immunologically identical. 10. Virus III and vaccine virus are immunologically distinct. 11. Virus III and the virus of symptomatic herpes are immunologically distinct. 12. No passive immunity to Virus III could be demonstrated in rabbits which had received intravenous injections of 5 to 10 cc. of serum or whole blood from patients convalescent from varicella. 13. Sera from two normal adults and from fourteen patients convalescent from varicella did not neutralize Virus III in vitro. 14. Rabbits could not be actively immunized against Virus III by injections of whole blood, vesicle fluid, or nasal washings from patients with varicella. 15. Four of twenty sera collected from stock rabbits of different ages, 20 per cent, neutralized Virus III in vitro. The animals whose sera neutralized Virus III failed to show a reaction at the site of intradermal inoculations with the same virus. About 15 per cent of 200 young stock rabbits (1,800 gm.) used in routine transfers were found to be refractory to Virus III, as evidenced by a failure to react to intradermal inoculations of the virus. 16. No susceptibility to Virus III was observed in guinea pigs, mice, or monkeys. 17. A volunteer who had never suffered from varicella experienced no general reaction and only a mild local one following an intradermal inoculation of Virus III. A volunteer who had had chicken-pox in childhood experienced a moderate general action, viz., fever, headache, backache, and general malaise, and also a moderate local reaction, viz., redness, swelling, tenderness, and pain, following an intradermal inoculation of Virus III. 18. The study of the immunological reactions has failed to bring any evidence that the virus under investigation bears an etiologic relationship to varicella.

Microscopical observations on immune precipitates formedin vitroon the surface of hymenolepid tapeworms

Parasitology ◽  
1994 ◽  
Vol 109 (2) ◽  
pp. 243-248 ◽  
Author(s):  
D. Hoole ◽  
J. Andreassen ◽  
D. Birklund
Keyword(s):  
Electron Microscopy ◽  
Immune Serum ◽  
Culture Vessel ◽  
Serum Antibodies ◽  
Secretory Products ◽  
Hymenolepis Microstoma

SUMMARYFour-day-old worms of the tapewormsHymenolepis microstoma,H. diminutaandH. nanaand newly excystedH. microstomawere exposed in vitro at 37 °C to immune serum from mice infected for 4–1 2 weeks withH. microstoma. Worms were fixed for electron microscopy after intervals of 5 min to 96 h. Within 10–15 min an homogeneous precipitate occurred between the microtriches of 4-day-oldH. microstomaandH. nana, while on some areas ofH. microstomathe precipitate extended distal to the microthrix border and contained small vesicles (30 nm in diameter) and shed microtriches. InH. diminutaprecipitates were not found until 2 h post-incubation. The thickness of the precipitate and the number of small vesicles and shed microtriches increased with time after incubation. Since a similar precipitate occurred on worms kept in complement-depleted immune serum, antibodies alone may induce immune damage. The precipitate on newly excystedH. microstomalacked microthrix fragments. After 48 h an extensive precipitate was found protruding from the rostellar glands on someH. microstoma, and within the culture vessel. Antibodies may therefore be complexing with tapeworm secretory products.

Aerosol Q Fever Infection of the Nude Mouse

1981 ◽  
Vol 18 (5) ◽  
pp. 672-683 ◽  
Author(s):  
W. C. Hall ◽  
J. D. White ◽  
R. A. Kishimoto ◽  
R. E. Whitmire
Keyword(s):  
Electron Microscopy ◽  
Nude Mice ◽  
Q Fever ◽  
Fluorescent Antibody ◽  
Fluorescent Antibody Technique ◽  
Indirect Fluorescent Antibody ◽  
Antibody Technique ◽  
Athymic Nude Mice ◽  
Antibody Titers ◽  
Morphologic Changes

Athymic nude mice and euthymic littermate controls were exposed to 104 Coxiella burnetii organisms by small-particle aerosol. Antibody response with and without 2-mercaptoethanol treatment of serum was determined at various intervals after infection and serial kills were done to determine morphologic changes in both mouse phenotypes. Total antibody titers determined by the indirect fluorescent antibody technique to phase I and phase II C. burnetii were identical for both groups of mice. Microagglutinin titers determined on days 28 and 33 were abolished by 2-mercaptoethanol treatment of serum from both phenotypes, indicating that the antibody probably resided in the IgM fraction. Microscopically, the reaction to C. burnetii infection was similar in nude and euthymic mice on days 7 and 14. Later, the number and size of lesions attributable to Q fever diminished in euthymic mice. Infection was progressive in nude mice, with macrophage infiltration of most tissues, especially spleen and liver. Numerous rickettsiae were seen by immunofluorescence and electron microscopy in phagocytic vesicles of macrophages, many of which were dilated, giving the macrophage a vacuolated appearance. Results suggest that clearance of C. burnetii infection in mice is dependent upon thymus-derived lymphocytes.

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