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Characteristics Of Conjugative R-Plasmids From Pathogenic Avian Escherichia Coli, Richard E. Wooley, Kathy R. Spears, Lisa K. Nolan, John Brown, Mark A. Dekich Jun 1992

Characteristics Of Conjugative R-Plasmids From Pathogenic Avian Escherichia Coli, Richard E. Wooley, Kathy R. Spears, Lisa K. Nolan, John Brown, Mark A. Dekich

Lisa K. Nolan

Three of four virulent avian Escherichia coli isolates transferred a single large molecular-weight R-plasmid to two recipient E. coli strains. Antibiotic resistances transferred included streptomycin (two isolates) and streptomycin-tetracycline-sulfa (one isolate). Production of colicin and siderophores, complement resistance, and embryo lethality present in the virulent isolates were not transferred to recipient organisms. From the results, it appears that the R-plasmids of these virulent avian E. coli are not associated with virulence.


Animal Model Of Human Disease: Bovine Leukocyte Adhesion Deficiency: Beta2 Integrin Deficiency In Young Holstein Cattle, Marcus E. Kehrli Jr., Mark R. Ackermann, Dale E. Shuster, Martin J. Van Der Maaten, Frank C. Schmalstieg, Donald C. Anderson, Bonnie J. Hughes Jun 1992

Animal Model Of Human Disease: Bovine Leukocyte Adhesion Deficiency: Beta2 Integrin Deficiency In Young Holstein Cattle, Marcus E. Kehrli Jr., Mark R. Ackermann, Dale E. Shuster, Martin J. Van Der Maaten, Frank C. Schmalstieg, Donald C. Anderson, Bonnie J. Hughes

Mark R. Ackermann

Leukocyte adhesion deficiency (LAD), is a rare, autosomal recessive disorder caused by a lack or partial absence of a family of leukocyte integrins, Mac-1, LFA-1, and p150,95.1 The leukocyte (32) integrins are glycoproteins essential for normal leukocyte-endothelial cell adherence and emigration. Affected children develop recurrent bacterial infections, persistent leukocytosis, severe hypoplasia of lymphoid tissues and isolated neutrophils, eosinophils, macrophages, and lymphocytes have abnormal function when tested in vitro. Most patients without bone marrow transplants die at an early age.


Use Of Rats To Compare Atrophic Rhinitis Vaccines For Protection Against Effects Of Heat-Labile Protein Toxin Produced By Pasteurella Multocida Serogroup D, J. R. Thurston, R. B. Rimler, Mark R. Ackermann, N. F. Cheville Jun 1992

Use Of Rats To Compare Atrophic Rhinitis Vaccines For Protection Against Effects Of Heat-Labile Protein Toxin Produced By Pasteurella Multocida Serogroup D, J. R. Thurston, R. B. Rimler, Mark R. Ackermann, N. F. Cheville

Mark R. Ackermann

Four bacterin-toxoid and three bacterin commercial vaccines against atrophic rhinitis were tested in rats for their capacity to immunize against the lethal and systemic effects of purified heat-labile protein toxin (D-toxin) produced by Pasteurella multocida serogroup D. Only one bacterin-toxoid vaccine stimulated sufficient immunity to prevent the death of all rats challenged with D-toxin. None of the vaccines prevented weight loss, leukocytosis or increases in serum complement titers in rats challenged with D-toxin. Rats provide an inexpensive animal model for testing the capacity of vaccines to generate antitoxic immunity against the lethal and systemic effects of D-toxin.


Comparison Of A Complement Resistance Test, A Chicken Embryo Lethality Test, And The Chicken Lethality Test For Determining Virulence Of Avian Escherichia Coli, Lisa K. Nolan, Richard E. Wooley, John Brown, Kathy R. Spears, H. W. Dickerson, Mark Dekich Jun 1992

Comparison Of A Complement Resistance Test, A Chicken Embryo Lethality Test, And The Chicken Lethality Test For Determining Virulence Of Avian Escherichia Coli, Lisa K. Nolan, Richard E. Wooley, John Brown, Kathy R. Spears, H. W. Dickerson, Mark Dekich

Lisa K. Nolan

Results with four pathogenic avian Escherichia coli isolates and one avirulent isolate in a complement resistance test, a chicken lethality test, and a chicken embryo lethality test were compared. Results of the complement resistance test with these isolates were highly correlated to results of the chicken lethality test of virulence. The chicken embryo test yielded results that were of a medium positive correlation with the chicken lethality results. The results of the complement resistance and chicken embryo lethality tests were highly correlated.


Transposon Mutagenesis Used To Study The Role Of Complement Resistance In The Virulence Of An Avian Escherichia Coli Isolate, Lisa K. Nolan, Richard E. Wooley, Richard K. Cooper Jun 1992

Transposon Mutagenesis Used To Study The Role Of Complement Resistance In The Virulence Of An Avian Escherichia Coli Isolate, Lisa K. Nolan, Richard E. Wooley, Richard K. Cooper

Lisa K. Nolan

The role of complement resistance in the virulence of an avian Escherichia coli isolate was examined with transposon mutagenesis. A suicide plasmid containing a kanamycin-encoding mini-transposon was used to transform a virulent complement-resistant avian E. coli isolate. A less resistant mutant was identified that contained a transposon insertion in a plasmid and in the chromosome. This loss of complement resistance was associated with a drop in virulence in an embryo assay. No other phenotypic changes were detected in the mutant. These results suggest that complement resistance is associated with the virulence of this organism.


Intestinal Adenocarcinoma Of The Ileocecal Junction In A Chicken, James R. Andreasen Jr., Claire B. Andreasen Jan 1992

Intestinal Adenocarcinoma Of The Ileocecal Junction In A Chicken, James R. Andreasen Jr., Claire B. Andreasen

Claire B. Andreasen

An 89-week-old male chicken was presented with signs of depression, emaciation, and weakness. At necropsy, a stricture was found at the ileocecal junction that resulted in blockage and dilation of the ileum proximal to the stricture. Histologically, neoplastic epithelial cells that contained mucin had invaded the intestinal wall and produced a fibrous connective tissue reaction. The lesion was diagnosed as scirrhous intestinal adenocarcinoma.


Light Microscopic And Ultrastructural Pathology Of Seminiferous Tubules Of Rats Given Multiple Doses Of Pasteurella Multocida Group D Protein Toxin, Mark R. Ackermann, James P. Tappe Jr., John R. Thurston, Richard B. Rimler, Dale E. Shuster, Norman F. Cheville Jan 1992

Light Microscopic And Ultrastructural Pathology Of Seminiferous Tubules Of Rats Given Multiple Doses Of Pasteurella Multocida Group D Protein Toxin, Mark R. Ackermann, James P. Tappe Jr., John R. Thurston, Richard B. Rimler, Dale E. Shuster, Norman F. Cheville

Mark R. Ackermann

Male Holtzman rats were given subcutaneous doses of a purified Pasteurella multocida group D heat-labile toxin on alternate days for up to 22 days. Rats were necropsied at 18 days or 36 days (14 days after last dose of toxin) or when moribund, and testicles were taken for histologic and ultrastructural examination. Other selected tissues, including liver and spleen, were taken for histologic examination. Histologically, testicular and splenic lesions occurred more consistently and at much smaller doses when compared with lesions in other target organs such as liver. Testicular and splenic lesions were present in all rats (6/6) given 0.8 …


Comparison Of A Quantitative Microtiter Method, A Quantitative Automated Method, And The Plate-Count Method For Determining Microbial Complement Resistance, Margie D. Lee, Richard E. Wooley, John Brown, Kathy R. Spears, Lisa K. Nolan, Emmett B. Shotts Jr. Dec 1991

Comparison Of A Quantitative Microtiter Method, A Quantitative Automated Method, And The Plate-Count Method For Determining Microbial Complement Resistance, Margie D. Lee, Richard E. Wooley, John Brown, Kathy R. Spears, Lisa K. Nolan, Emmett B. Shotts Jr.

Lisa K. Nolan

A quantitative microtiter method for determining the degree of complement resistance or sensitivity of microorganisms is described. The microtiter method is compared with a quantitative automated system and the standard plate-count technique. Data were accumulated from 30 avian Escherichia coli isolates incubated at 35 C with either chicken plasma or heat-inactivated chicken plasma. Analysis of data generated by the automated system and plate-count techniques resulted in a classification of the microorganisms into three groups: those sensitive to the action of complement; those of intermediate sensitivity to the action of complement; and those resistant to the action of complement. Although the …


Comparison Of Chicken Plasma And Guinea Pig Serum In A Quantitative Microtiter Method Of Determining Microbial Complement Resistance, Richard E. Wooley, John Brown, Kathy R. Spears, Lisa K. Nolan Dec 1991

Comparison Of Chicken Plasma And Guinea Pig Serum In A Quantitative Microtiter Method Of Determining Microbial Complement Resistance, Richard E. Wooley, John Brown, Kathy R. Spears, Lisa K. Nolan

Lisa K. Nolan

Y. A quantitative microtiter method using chicken plasma is described for determining the degree of complement resistance or sensitivity of avian Escherichia coli isolates. Results obtained with the microtiter method using chicken plasma were compared with results obtained using commercially available standardized guinea pig serum as the source of complement. The test organisms consisted of five isolates of E. coli isolated from chickens. Three isolates were from flocks with colisepticemia; one was from a flock with omphalitis; and one isolate was a non-pathogenic control. Data were accumulated from the five avian E. coli isolates incubated at 35 C with either …


Bronchiolar Metaplasia And Ulex Europaeus Agglutinin I (Uea-I) Affinity In Mycoplasma Hyopneumoniae-Infected Lungs Of Six Pigs, Mark R. Ackermann, M. C. Debey, B. M. Debey Nov 1991

Bronchiolar Metaplasia And Ulex Europaeus Agglutinin I (Uea-I) Affinity In Mycoplasma Hyopneumoniae-Infected Lungs Of Six Pigs, Mark R. Ackermann, M. C. Debey, B. M. Debey

Mark R. Ackermann

Mycoplasma hyopneumoniae adheres to the cilia and apical plasma membrane of cells that line the trachea, bronchi, and bron ch ioles. Colonization result s in ciliostasis and peribronchial and peribronchi olar nod ular aggregates of lymphocytes and plasma cells.">Altho ugh adhesion-receptor interaction s between the organism and respiratory epithelial cells have been examined, little attention has been given to the morphologic and phenotypic changes that may occur in cells lining bron chioles during infection. In this study, we describe morphologic cha nges and differenc es in lectin staining patt ern s in the bron chi oles from lungs of …


Experimental Model Of Atrophic Rhinitis In Gnotobiotic Pigs, Mark R. Ackermann, R. B. Rimler, J. R. Thurston Oct 1991

Experimental Model Of Atrophic Rhinitis In Gnotobiotic Pigs, Mark R. Ackermann, R. B. Rimler, J. R. Thurston

Mark R. Ackermann

To study the pathogenesis of atrophic rhinitis, gnotobiotic pigs (n = 6) were inoculated intranasally with a sterile sonicate of a toxigenic strain of Bordetella bronchiseptica (0.16 mg of protein per ml) at 5 days of age, and they were then inoculated intranasally with 1 ml (5,250 CFU/ml) of a live, toxigenic strain of Pasteurella multocida at 7 days of age. Pigs were necropsied at 2, 5, 9, 14, 21, and 28 days postinoculation; those pigs necropsied after 5 days had developed turbinate atrophy. Other gnotobiotic pigs received the following inoculation protocols: (i) a sterile sonicate of a nontoxigenic strain …


Colonization Of The Pharyngeal Tonsil And Respiratory Tract Of The Gnotobiotic Pig By A Toxigenic Strain Of Pasteurella Multocida Type D, Mark R. Ackermann, N. F. Cheville, J. E. Gallagher Jul 1991

Colonization Of The Pharyngeal Tonsil And Respiratory Tract Of The Gnotobiotic Pig By A Toxigenic Strain Of Pasteurella Multocida Type D, Mark R. Ackermann, N. F. Cheville, J. E. Gallagher

Mark R. Ackermann

Seven-day-old gnotobiotic pigs were inoculated intranasally with Pasteurella multocida and euthanatized 2, 5, 9, and 14 days after inoculation. Tissues from the oropharynx and respiratory tract of pigs were cultured quantitatively and analyzed microscopically. Pigs remained afebrile and alert, except one that died of acute fibrinopurulent pneumonia. Pasteurella multocida was isolated in greatest numbers from the pharyngeal tonsils, but only in low numbers from turbinate, trachea, lung, spleen, and liver. Significant histologic changes were limited to the tonsil. Infected pigs developed mild tonsillitis with lymphocytic hyperplasia, and accumulation of cell debris and bacteria in crypts. Capsular antigens of P. multocida, …


Lectin Histochemistry Of Trachea And Lung Of Healthy Turkeys (Meleagris Gallopavo) And Turkeys With Pneumonia, Mark R. Ackermann, N. F. Cheville, P. G. Detilleux May 1991

Lectin Histochemistry Of Trachea And Lung Of Healthy Turkeys (Meleagris Gallopavo) And Turkeys With Pneumonia, Mark R. Ackermann, N. F. Cheville, P. G. Detilleux

Mark R. Ackermann

Thirteen lectins were used to characterize lectin-binding specificity of glycoconjugates on sections of formalin-fixed lung and trachea from seven normal turkeys, two turkeys with acute pneumonia, and two turkeys with chronic pneumonia. Neuraminidase was used to digest sialic acid residues. One N-acetylgalactosamine-binding lectin and two N-acetylgalactosamine/galactose-binding lectins stained the apical membrane and cytoplasm of multifocal cells that lined air atria and hyperplastic granular cells. Other lectins in these groups stained ciliated cells of the trachea and bronchi and air capillary epithelial cells. Sialic acid residues were on apical surfaces of ciliated and nonciliated tracheal and bronchial lining cells, air capillary …


Immunity Induced In Rats Vaccinated With Toxoid Prepared From Heat-Labile Toxin Produced By Pasteurella Multocida Serogroup D, J. R. Thurston, R. B. Rimler, Mark R. Ackermann, N. F. Cheville, J. M. Sacks Apr 1991

Immunity Induced In Rats Vaccinated With Toxoid Prepared From Heat-Labile Toxin Produced By Pasteurella Multocida Serogroup D, J. R. Thurston, R. B. Rimler, Mark R. Ackermann, N. F. Cheville, J. M. Sacks

Mark R. Ackermann

Rats were vaccinated with a toxoid (D-toxoid) prepared from purified heat-labile toxin (D-toxin) produced by Pasteurella multocida serogroup D. Vaccination of rats with D-toxoid prevented death and other effects of D-toxin (hepatic necrosis, development of elevated leukocyte counts, lymphopenia, neutrophilia, and elevated complement titers) that occurred in phosphate buffered saline (PBS)-vaccinated control rats.


Evaluation Of Chicken Heterophil Adherence, Claire B. Andreasen, Kenneth S. Latimer, W. L. Steffens Jan 1990

Evaluation Of Chicken Heterophil Adherence, Claire B. Andreasen, Kenneth S. Latimer, W. L. Steffens

Claire B. Andreasen

Adherence of chicken heterophils was evaluated at 37 C using preconstructed columns containing various weights of nylon fiber (75 mg, 100 mg, or 125 mg) and whole blood anticoagulated with sodium heparin or 10% disodium ethylenediamine tetraacetic acid (EDTA). Additionally, 50-mg and 75-mg nylon fiber columns incubated at 41 C were used to evaluate heterophil adherence at an increased temperature. The mean percent adherence for heparin-anticoagulated blood applied to 75-mg, 100-mg, and 125-mg nylon fiber columns at 37 C was 76%, 92% and 97.4%, respectively. Samples applied to 50-mg and 75-mg columns at 41 C had adherence values of 27% …


Organ Hypertrophy And Responses Of Colon Microbial Populations Of Growing Swine To High Dietary Protein, James S. Dickson, Wilson G. Pond, Vincent H. Varel, Friday O. I. Anugwa, Gary S. Ross Jan 1990

Organ Hypertrophy And Responses Of Colon Microbial Populations Of Growing Swine To High Dietary Protein, James S. Dickson, Wilson G. Pond, Vincent H. Varel, Friday O. I. Anugwa, Gary S. Ross

James S. Dickson

Thirty-two castrated male crossbred growing pigs (average initial wt 26.9 kg) were used to determine the effect of a high level of dietary protein (37%) compared with a normal level of protein (15%) on enterobacteria and Campylobactersp. inhabitation in the large intestine and on visceral organ hypertrophy and the interrelationships between these two factors. Pigs were kept in pairs (eight pens of two pigs/diet) and fed their respective diets ad libitum. Eight pigs (two pens of two pigs fed each diet) were killed at wk 4, 8. 12 and 16 without fasting. Fecal samples were obtained every 2 wk from …


Separation Of Turkey Heterophils From Blood Using Two-Step Ficoll-Hypaque Discontinuous Gradients, Kenneth S. Latimer, Ingrid M. Kircher, Claire B. Andreasen Jan 1989

Separation Of Turkey Heterophils From Blood Using Two-Step Ficoll-Hypaque Discontinuous Gradients, Kenneth S. Latimer, Ingrid M. Kircher, Claire B. Andreasen

Claire B. Andreasen

A method is presented to separate turkey heterophils from anticoagulated whole blood using two-step Ficoll-Hypaque discontinuous gradients and ammonium chloride lysis of contaminating erythrocytes. Heterophils can be isolated from multiple blood samples within 3 to 4 hours. Using this technique, 66.4 +- 18.4% (mean +- standard deviation) of blood heterophils were harvested. Final cell isolates averaged 96.0 +- 2.9% heterophils with few contaminating eosinophils (2.5 +- 2.3%) or basophils (1.6 +- 1.8%). Cell viability, as determined by trypan blue dye exclusion, was 98.0 +- 1.4%.


Determination Of Chicken And Turkey Plasma And Serum Protein Concentrations By Refractometry And The Biuret Method, Claire B. Andreasen, Kenneth S. Latimer, Ingrid M. Kircher, John Brown Jan 1989

Determination Of Chicken And Turkey Plasma And Serum Protein Concentrations By Refractometry And The Biuret Method, Claire B. Andreasen, Kenneth S. Latimer, Ingrid M. Kircher, John Brown

Claire B. Andreasen

Plasma and serum protein concentrations were determined in chickens and turkeys by refractometry (with human and veterinary refractometers)and by the biuret method. Chicken and turkey serum protein values were significantly lower than respective plasma protein values according to both methods. Refractometer readings for both plasma and serum correlated closely with the results of the biuret test (r2 = 0.72 to 0.97). These findings indicate that plasma and serum protein values may be determined accurately in chickens and turkeys with a handheld refractometer.


Separation Of Avian Heterophils From Blood Using Ficoll-Hypaque Discontinuous Gradients, Claire B. Andreasen, Kenneth S. Latimer Jan 1989

Separation Of Avian Heterophils From Blood Using Ficoll-Hypaque Discontinuous Gradients, Claire B. Andreasen, Kenneth S. Latimer

Claire B. Andreasen

Rapid separation of avian heterophils from anticoagulated whole blood was achieved using Ficoll-Hypaque discontinuous gradients. An average of 14.4% of blood heterophils was harvested with a mean purity exceeding 99%. Heterophil viability, as determined by trypan blue dye exclusion, averaged 99.8%. The integrity of isolated heterophils was evaluated by cytochemical staining and ultrastructural examination. Cytochemical staining reactions of heterophils in whole blood and of isolated cell suspensions were similar. No ultrastructural abnormalities were observed. Using this procedure, viable intact heterophils were rapidly isolated from blood with an acceptable cell yield and purity for cell function studies.


Acute Fibrinopurulent Blepharitis And Conjunctivitis Associated With Staphylococcus Hyicus, Escherichia Coli, And Streptococcus Sp. In Chickens And Turkeys, N. F. Cheville, J. Tappe, Mark R. Ackermann, A. Jensen Sep 1988

Acute Fibrinopurulent Blepharitis And Conjunctivitis Associated With Staphylococcus Hyicus, Escherichia Coli, And Streptococcus Sp. In Chickens And Turkeys, N. F. Cheville, J. Tappe, Mark R. Ackermann, A. Jensen

Mark R. Ackermann

Multiple outbreaks of acute severe fibrinopurulent lesions of the eyelids occurred in chickens and turkeys. Lesions began as tiny foci of epidermal necrosis and ulceration and spread to involve the entire eyelid. Scabs overlying the epidermis contained large gram-positive cocci; lesser numbers of small cocci and gram-negative bacilli were in more superficial areas. Staphylococcus hyicus was isolated from birds in all stages of the disease. Escherichia coli and Streptococcus sp. were isolated only during severe stages; no anaerobic bacterial pathogens were isolated. Vasculitis and perivascular lymphocytic infiltrates in deep layers of the dermis suggested that a staphylococcal toxin may have …


Bovine Ileal Dome Lymphoepithelial Cells: Endocytosis And Transport Of Brucella Abortus Strain 19, Mark R. Ackermann, N. F. Cheville, B. L. Deyoe Jan 1988

Bovine Ileal Dome Lymphoepithelial Cells: Endocytosis And Transport Of Brucella Abortus Strain 19, Mark R. Ackermann, N. F. Cheville, B. L. Deyoe

Mark R. Ackermann

Ligated ileal loops of calves were inoculated with Brucella abortus and examined at 2, 4, 6, 10, and 24 hours post-inoculation. B. abortus was identified by light and electron microscopy using immunoperoxidase and antibody-coated colloidal gold techniques. B. abortus was detected in vesicles, phagolysosomes, and large vacuoles of lymphoepithelial cells. Numbers of intracellular bacteria decreased with time after inoculation. B. abortus was also seen between and below lymphoepithelial cells and free in the dome interstitium and intestinal lymph vessels. Neutrophils and macrophages in both epithelium and lamina propria contained intact or degraded bacteria within phagosomes, phagolysosomes, and multivesicular bodies. These …