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2.
J Anim Sci ; 95(1): 279-290, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28177370

ABSTRACT

Heat stress (HS) may result in economic losses to pig producers across the USA and worldwide. Despite significant advancements in management practices, HS continues to be a challenge. In this study, an in-feed antibiotic (carbadox, CBX) and antibiotic alternatives ( [XPC], and [SGX] fermentation products) were evaluated in a standard pig starter diet as mitigations against the negative effects of HS in pigs. A total of 100 gilts were obtained at weaning (6.87 ± 0.82 kg BW, 19.36 ± 0.72 d of age) and randomly assigned to dietary treatments (2 rooms/treatment, 2 pens/room, 6 to 7 pigs/pen). After 4 wk of dietary acclimation, half of the pigs in each dietary group (1 room/dietary treatment) were exposed to repeated heat stress conditions (RHS; daily cycles of 19 h at 25°C and 5 h at 40°C, repeated for 9 d), and the remaining pigs were housed at constant thermal neutral temperature (25°C, [NHS]). Pigs subjected to RHS had elevated skin surface temperature ( < 0.05; average 41.7°C) and respiration rate ( < 0.05; 199 breaths per minute (bpm) during HS, and overall reduced ( < 0.05) BW, ADG, ADFI, and G:F regardless of dietary treatment. Independent of diet, RHS pigs had significantly shorter ( < 0.05) jejunum villi on d 3 and d 9 compared to NHS pigs. Heat stress resulted in decreased villus height to crypt depth ratio (V:C) in pigs fed with control diet with no added feed additive (NON) and CBX diets at d 3, whereas the pigs fed diets containing XPC or SGX showed no decrease. Transcriptional expression of genes involved in cellular stress (, , , ), tight junction integrity (, , ), and immune response (, , and ) were measured in the ileum mucosa. Pigs in all dietary treatments subjected to RHS had significantly higher ( < 0.05) transcript levels of and , and an upward trend ( < 0.07) of mRNA expression. RHS pigs had higher ( < 0.05) transcript levels of and in NON diet, in XPC and CBX diets, and in SGX diet compared to the respective diet-matched pigs in the NHS conditions. Neither RHS nor diet affected peripheral natural killer () cell numbers or NK cell lytic activity. In conclusion, pigs subjected to RHS had decreased performance, and supplementation with fermentation products in the feed (XPC and SGX) protected pigs from injury to the jejunum mucosa.


Subject(s)
Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Dietary Supplements , Swine/physiology , Animals , Anti-Bacterial Agents/pharmacology , Diet/veterinary , Female , Fermentation , Hot Temperature/adverse effects , Ileum/drug effects , Intestinal Mucosa/drug effects , Random Allocation , Stress, Physiological , Swine/immunology , Weaning
3.
Cochlear Implants Int ; 12(1): 10-20, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21756454

ABSTRACT

This study was undertaken to evaluate the musical sounds in cochlear implants (MuSIC) perception test, created to assess the music-listening abilities of cochlear implant (CI) users. Thirty-one unilateral MED-EL COMBI 40+/PULSARCI(100) users and a control group of 67 adults with normal hearing (NH) participated. The MuSIC test comprises six objective and two subjective modules employing approximately 2800 musical files recorded from non-synthesized instruments. A subset was used for comparing CI and NH participants' results. CI and NH participants performed significantly differently on: pitch discrimination, melody discrimination, chord discrimination, instrument detection, and instrument identification. No significant difference in performance was seen on the subtests of rhythm discrimination or dissonance rating and emotion rating. The MuSIC test was found to be a valuable tool for assessing music perception in CI users and NH participants, whether investigating one aspect of music perception in depth or conducting a broad survey of music perception.


Subject(s)
Auditory Perception/physiology , Cochlear Implants , Music , Pitch Perception , Acoustic Impedance Tests , Adult , Aged , Case-Control Studies , Cochlear Implantation/methods , Confidence Intervals , Electric Stimulation/methods , Female , Humans , Male , Middle Aged , Multivariate Analysis , Pitch Discrimination , Reference Values , Sensitivity and Specificity , Statistics, Nonparametric
4.
Theriogenology ; 76(2): 351-60, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21496897

ABSTRACT

The objectives were to determine whether the amount of porcine circovirus type 2 (PCV2) shed in semen increased in boars experimentally coinfected with Mycoplasma hyopneumoniae (MHYO), and whether PCV2 vaccination of boars prior to PCV2 exposure reduced PCV2 viremia and virus shedding in semen. Twelve specific-pathogen-free PCV2- and MHYO-naïve boars were randomly and equally assigned to one of four groups. Six boars were vaccinated against PCV2 (VAC) on Day 0; three PCV2 vaccinated and three non-vaccinated boars were inoculated with MHYO on Day 21, and all boars were challenged with PCV2 on Day 35. The four treatment groups included PCV2-Infected (I), VAC-PCV2-I, MHYO-PCV2-Coinfected (CoI), and VAC-MHYO-PCV2-CoI. Semen, blood swabs, feces, and serum samples were collected weekly until Day 70. All vaccinated boars had seroconverted to PCV2 by Day 35. Between Days 28 and 35, MHYO boars developed moderate respiratory disease, characterized by coughing, respiratory distress, mucopurulent nasal discharge and loss of body condition. One MHYO-PCV2-CoI boar died on Day 50. Boars in the PCV2-I and MHYO-PCV2-CoI groups had significantly higher PCV2 DNA loads in blood swabs than the remaining boars. Moreover, PCV2 vaccination significantly reduced the incidence and amount of PCV2 shedding in semen and feces. In summary, although concurrent MHYO infection did not influence PCV2 shedding patterns, coinfection of boars with PCV2 and MHYO resulted in severe clinical disease and viral shedding was significantly decreased by PCV2 vaccination.


Subject(s)
Circoviridae Infections/veterinary , Circovirus/immunology , Pneumonia of Swine, Mycoplasmal , Semen/virology , Swine Diseases/prevention & control , Vaccination/veterinary , Animals , Circoviridae Infections/complications , Circoviridae Infections/prevention & control , Circovirus/genetics , DNA, Viral , Male , Mycoplasma hyopneumoniae , Swine , Swine Diseases/microbiology , Swine Diseases/virology , Viral Load , Viral Vaccines , Virus Shedding
5.
Adv Otorhinolaryngol ; 67: 70-80, 2010.
Article in English | MEDLINE | ID: mdl-19955723

ABSTRACT

AIMS: This study compared the music perception abilities of 13 electric acoustic stimulation (EAS) users with two control groups: unilateral cochlear implant (CI) users and normal-hearing (NH) listeners. METHODS: Groups were matched according to age and musical experience before hearing loss (HL) and tested using the Musical Sounds in Cochlear Implants (Mu.S.I.C.) test. RESULTS: No difference was found on rhythm perception, chord discrimination, dissonance rating, and emotion rating subtest performance between groups. Mean frequency discrimination scores were significantly better in EAS participants than in CI participants and not significantly worse than in NH participants. However, the EAS and CI groups scored similarly (significantly worse than NH participants) on both instrument detection and identification. Results for EAS participants were not significantly worse when the hearing aid component was removed. Frequency of listening to music before HL was negatively correlated with EAS participants' frequency discrimination scores, though singing and playing an instrument appeared to have no effect. EAS participants who indicated many reasons for listening to music and who listen to many genres after implantation scored higher on instrument detection and instrument identification. Better results on these two subtests were correlated with EAS participants' better postoperative auditory thresholds at 250 and 500 Hz. CONCLUSIONS: Though EAS participants performed better on music perception testing (though not timbre-based tasks) than CI participants, their scores did not reach the level of NH participants. This indicates that acoustic hearing in the low frequencies is helpful for music perception, though not the only important factor.


Subject(s)
Acoustic Stimulation/methods , Auditory Perception/physiology , Auditory Threshold/physiology , Cochlear Implants , Electric Stimulation/methods , Hearing Loss/physiopathology , Music , Adult , Aged , Follow-Up Studies , Hearing Loss/therapy , Humans , Middle Aged , Prognosis
6.
Viral Immunol ; 22(3): 173-80, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19435413

ABSTRACT

In this study, pigs were injected with a nonreplicating human adenovirus type 5 vector expressing porcine interferon-alpha (Ad5-pIFN-alpha) and then challenged with porcine reproductive and respiratory syndrome virus (PRRSV) to determine whether the presence of increased levels of IFN-alpha would decrease viral replication and/or disease. Groups of 10 pigs each were inoculated with Ad5-pIFN-alpha and not challenged, Ad5-pIFN-alpha and challenged with PRRSV 1 d later, or inoculated with a control adenovirus that does not express IFN-alpha (Ad5-null) and challenged 1 d later with PRRSV. IFN-alpha levels in all pigs inoculated with the Ad5-pIFN-alpha were elevated the day of challenge (1 d after inoculation), but were undetectable by 3 d after inoculation in the pigs that were not challenged with PRRSV. Pigs inoculated with Ad5-pIFN-alpha and challenged with PRRSV had lower febrile responses, a decreased percentage of lung involvement at 10 d post-infection, delayed viremia and antibody response, and higher serum IFN-alpha levels as a result of PRRSV infection, compared to pigs inoculated with Ad5-null and challenged with PRRSV. These results indicate that IFN-alpha can have protective effects if present during the time of infection with PRRSV.


Subject(s)
Adenoviridae/genetics , Interferon-alpha/biosynthesis , Interferon-alpha/immunology , Porcine Reproductive and Respiratory Syndrome/immunology , Porcine respiratory and reproductive syndrome virus/physiology , Virus Replication , Animals , Genetic Therapy/methods , Genetic Vectors , Interferon-alpha/blood , Interferon-gamma/blood , Lung/pathology , Porcine Reproductive and Respiratory Syndrome/pathology , Porcine Reproductive and Respiratory Syndrome/therapy , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Swine , Viremia
7.
Audiol Neurootol ; 14(5): 315-26, 2009.
Article in English | MEDLINE | ID: mdl-19372650

ABSTRACT

Music plays an important role in the daily life of cochlear implant (CI) users, but electrical hearing and speech processing pose challenges for enjoying music. Studies of unilateral CI (UCI) users' music perception have found that these subjects have little difficulty recognizing tempo and rhythm but great difficulty with pitch, interval and melody. The present study is an initial step towards understanding music perception in bilateral CI (BCI) users. The Munich Music Questionnaire was used to investigate music listening habits and enjoyment in 23 BCI users compared to 2 control groups: 23 UCI users and 23 normal-hearing (NH) listeners. Bilateral users appeared to have a number of advantages over unilateral users, though their enjoyment of music did not reach the level of NH listeners.


Subject(s)
Auditory Perceptual Disorders/psychology , Cochlear Implants , Hearing Loss, Bilateral/psychology , Hearing , Music/psychology , Acoustic Stimulation/psychology , Adult , Aged , Auditory Perceptual Disorders/therapy , Hearing Loss, Bilateral/therapy , Humans , Middle Aged , Patient Satisfaction , Pitch Perception , Surveys and Questionnaires , Time Perception , Young Adult
8.
Fetal Diagn Ther ; 24(3): 203-10, 2008.
Article in English | MEDLINE | ID: mdl-18753758

ABSTRACT

OBJECTIVE: To investigate the influence of several magnetic resonance imaging (MRI) sequences on amniotic fluid temperature and intrauterine sound pressure. MATERIAL AND METHODS: Temperature and sound pressure measurements during MRI (1.5 T) in pregnant ewes were done. Linear levels and third octave band spectra were compared. RESULTS: No significant changes in the temperature of amniotic fluid were observed. Intrauterine summation levels reached peak levels up to 103.0 dB(A) before starting the MRI sequence and levels up to 116.0 dB(A) during a real-time sequence. Evaluating the octave band spectra, peak levels did not exceed 100.0 dB(L). CONCLUSIONS: Our delimited data revealed no harm for the fetus by an increase in amniotic fluid temperature or hazards for the fetal auditory system by different MRI sequences.


Subject(s)
Magnetic Resonance Imaging/adverse effects , Sheep/physiology , Sound , Temperature , Acoustics , Animals , Female , Fetus/physiology , Hearing/physiology , Pregnancy , Risk Assessment , Sound Spectrography
9.
Vet Microbiol ; 128(1-2): 36-47, 2008 Apr 01.
Article in English | MEDLINE | ID: mdl-18022332

ABSTRACT

Coinfection with two or more pathogens is a common occurrence in respiratory diseases of most species. The manner in which multiple pathogens interact is not always straightforward, however. Bordetella bronchiseptica and porcine respiratory coronavirus (PRCV) are respiratory pathogens of pigs whose relatives, B. pertussis and the SARS virus, cause respiratory disease in humans. In an initial experiment, the effect of coinfection of PRCV and B. bronchiseptica was examined in thirty, 4-week-old pigs (10 pigs/group) that were infected with either PRCV or B. bronchiseptica, or both PRCV and B. bronchiseptica. An additional 10 pigs served as sham infected controls. Five pigs from each group were euthanized at 4 and 10 days post-infection. Gross and histopathological lung lesions were more severe in the coinfected group as compared to the groups infected with B. bronchiseptica or PRCV alone. In order to investigate the potential role of proinflammatory cytokines in disease severity after coinfection, a second experiment was performed to examine cytokine transcription in alveolar macrophages from single and dually infected pigs. A total of 48 pigs were divided equally into groups as above, but 4 pigs from each group were euthanized at 1, 4 and 10 days post-infection. Coinfected pigs showed a greater and more sustained transcription of proinflammatory cytokines, especially IL-6 and MCP-1, than pigs infected with either PRCV or B. bronchiseptica alone. Thus, there appears to be a synergistic effect between PRCV and B. bronchiseptica with regards to proinflammatory cytokine transcription that may partially explain the increased severity of pneumonia in coinfected pigs.


Subject(s)
Bordetella Infections/veterinary , Bordetella bronchiseptica , Coronavirus Infections/veterinary , Porcine Respiratory Coronavirus , Respiratory Tract Infections/veterinary , Swine Diseases/pathology , Animals , Bordetella Infections/complications , Bordetella Infections/pathology , Bordetella bronchiseptica/isolation & purification , Coronavirus Infections/complications , Coronavirus Infections/pathology , Cytokines/analysis , Cytokines/biosynthesis , Cytokines/genetics , Gene Expression/immunology , Lung/immunology , Lung/pathology , Macrophages, Alveolar/chemistry , Macrophages, Alveolar/immunology , Porcine Respiratory Coronavirus/isolation & purification , Random Allocation , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/pathology , Respiratory Tract Infections/virology , Swine , Swine Diseases/microbiology , Swine Diseases/virology , Time Factors
10.
Vet Microbiol ; 125(3-4): 284-9, 2007 Dec 15.
Article in English | MEDLINE | ID: mdl-17624695

ABSTRACT

This experiment was designed to determine whether a Bordetella bronchiseptica mutant that does not produce dermonecrotic toxin (DNT) is still capable of predisposing pigs to infection with toxigenic Pasteurella multocida. Three groups of pigs were initially inoculated intranasally with a wild type B. bronchiseptica that produces DNT, an isogenic mutant of B. bronchiseptica that does not produce DNT, or PBS. All pigs were then challenged intranasally with a toxigenic strain of P. multocida 4 days later. P. multocida was recovered infrequently and in low numbers from pigs initially inoculated with PBS, and no turbinate atrophy was present in these pigs. P. multocida was isolated in similar numbers from the pigs initially inoculated with either the wild type or the DNT mutant of B. bronchiseptica, and turbinate atrophy of a similar magnitude was also seen in pigs from both of these groups. Thus, although the DNT has been shown to be responsible for much of the pathology seen during infection with B. bronchiseptica by itself, infection with non-DNT-producing strains can still predispose to secondary respiratory infections with P. multocida.


Subject(s)
Bordetella Infections/veterinary , Bordetella bronchiseptica/metabolism , Pasteurella Infections/veterinary , Pasteurella multocida/physiology , Rhinitis, Atrophic/veterinary , Swine Diseases/microbiology , Animals , Animals, Newborn , Bacterial Toxins/biosynthesis , Bordetella Infections/microbiology , Bordetella bronchiseptica/genetics , Colony Count, Microbial , Lung/microbiology , Nasal Cavity/microbiology , Palatine Tonsil/microbiology , Pasteurella Infections/microbiology , Rhinitis, Atrophic/microbiology , Swine , Trachea/microbiology , Transglutaminases/biosynthesis , Virulence Factors, Bordetella/biosynthesis
11.
Cochlear Implants Int ; 4 Suppl 1: 25-6, 2003 Dec.
Article in English | MEDLINE | ID: mdl-18792166
13.
Am J Vet Res ; 62(4): 521-5, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11327458

ABSTRACT

OBJECTIVE: To determine effects of intranasal inoculation with porcine reproductive and respiratory syndrome virus (PRRSV) or Bordetella bronchiseptica on challenge with nontoxigenic Pasteurella multocida in pigs. ANIMALS: Seventy 3-week-old pigs. PROCEDURE: In experiment 1, pigs were not inoculated (n= 10) or were inoculated with PRRSV (10), P. multocida (10), or PRRSV followed by challenge with P. multocida (10). In experiment 2, pigs were not inoculated (n = 10) or were inoculated with B. bronchiseptica (10) or PRRSV and B. bronchiseptica (10); all pigs were challenged with P. multocida. Five pigs from each group were necropsied 14 and 21 days after initial inoculations. RESULTS: Pasteurella multocida was not isolated from tissue specimens of pigs challenged with P. multocida alone or after inoculation with PRRSV. However, in pigs challenged after inoculation with B. bronchiseptica, P. multocida was isolated from specimens of the nasal cavity and tonsil of the soft palate. Number of bacteria isolated increased in pigs challenged after coinoculation with PRRSV and B. bronchiseptica, and all 3 agents were isolated from pneumonic lesions in these pigs. CONCLUSIONS AND CLINICAL RELEVANCE: Infection of pigs with B. bronchiseptica but not PRRSV prior to challenge with P. multocida resulted in colonization of the upper respiratory tract and tonsil of the soft palate with P. multocida. Coinfection with PRRSV and B. bronchiseptica predisposed pigs to infection of the upper respiratory tract and lung with P. multocida. Porcine reproductive and respiratory syndrome virus and B. bronchiseptica may interact to adversely affect respiratory tract defense mechanisms, leaving pigs especially vulnerable to infection with secondary agents such as P. multocida.


Subject(s)
Bordetella Infections/veterinary , Bordetella bronchiseptica/pathogenicity , Pasteurella Infections/veterinary , Pasteurella multocida/pathogenicity , Porcine Reproductive and Respiratory Syndrome/microbiology , Porcine respiratory and reproductive syndrome virus/pathogenicity , Swine Diseases/microbiology , Animals , Bacteremia , Bordetella Infections/complications , Bordetella Infections/microbiology , Lung/microbiology , Lung/pathology , Nasal Cavity/microbiology , Palate, Soft/microbiology , Palatine Tonsil/microbiology , Pasteurella Infections/complications , Pasteurella Infections/pathology , Random Allocation , Swine , Swine Diseases/virology , Viremia
14.
Infect Immun ; 69(4): 2137-43, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11254568

ABSTRACT

One means by which Bordetella bronchiseptica scavenges iron is through production of the siderophore alcaligin. A nonrevertible alcaligin mutant derived from the virulent strain 4609, designated DBB25, was constructed by insertion of a kanamycin resistance gene into alcA, one of the genes essential for alcaligin biosynthesis. The virulence of the alcA mutant in colostrum-deprived, caesarean-delivered piglets was compared with that of the parent strain in two experiments. At 1 week of age, piglets were inoculated with phosphate-buffered saline, 4609, or DBB25. Two piglets in each group were euthanatized on day 10 postinfection. The remainder were euthanatized at 21 days postinfection. Clinical signs, including fever, coughing, and sneezing, were present in both groups. Nasal washes performed 7, 14, and 21 days postinoculation demonstrated that strain DBB25 colonized the nasal cavity but did so at levels that were significantly less than those achieved by strain 4609. Analysis of colonization based on the number of CFU per gram of tissue recovered from the turbinate, trachea, and lung also demonstrated significant differences between DBB25 and 4609, at both day 10 and day 21 postinfection. Mild to moderate turbinate atrophy was apparent in pigs inoculated with strain 4609, while turbinates of those infected with strain DBB25 developed no or mild atrophy. We conclude from these results that siderophore production by B. bronchiseptica is not essential for colonization of swine but is required for maximal virulence. B. bronchiseptica mutants with nonrevertible defects in genes required for alcaligin synthesis may be candidates for evaluation as attenuated, live vaccine strains in conventionally reared pigs.


Subject(s)
Bordetella bronchiseptica/pathogenicity , Hydroxamic Acids , Siderophores/physiology , Animals , Animals, Newborn , Bordetella Infections/etiology , Bordetella Infections/pathology , Lung/microbiology , Lung/pathology , Mutation , Nasal Cavity/microbiology , Swine , Virulence
15.
Am J Vet Res ; 61(8): 892-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10951978

ABSTRACT

OBJECTIVE: To examine effects of co-infection with porcine reproductive and respiratory syndrome virus (PRRSV) and Bordetella bronchiseptica in pigs. ANIMALS: Forty 3-week-old pigs. Procedure-30 pigs (10 pigs/group) were inoculated with PRRSV, B bronchiseptica, or both. Ten noninoculated pigs were control animals. RESULTS: Clinical signs, febrile response, and decreased weight gain were most severe in the group inoculated with both organisms. The PRRSV was isolated from all pigs in both groups inoculated with virus. All pigs in both groups that received PRRSV had gross and microscopic lesions consistent with interstitial pneumonia. Bordetella bronchiseptica was cultured from all pigs in both groups inoculated with that bacterium. Colonization of anatomic sites by B bronchiseptica was comparable between both groups. Pigs in the group that received only B bronchiseptica lacked gross or microscopic lung lesions, and B bronchiseptica was not isolated from lung tissue. In the group inoculated with B bronchiseptica and PRRSV, 3 of 5 pigs 10 days after inoculation and 5 of 5 pigs 21 days after inoculation had gross and microscopic lesions consistent with bacterial bronchopneumonia, and B bronchiseptica was isolated from the lungs of 7 of those 10 pigs. CONCLUSIONS AND CLINICAL RELEVANCE: Clinical disease was exacerbated in co-infected pigs, including an increased febrile response, decreased weight gain, and B bronchiseptica-induced pneumonia. Bordetella bronchiseptica and PRRSV may circulate in a herd and cause subclinical infections. Therefore, co-infection with these organisms may cause clinical respiratory tract disease and leave pigs more susceptible to subsequent infection with opportunistic bacteria.


Subject(s)
Bordetella Infections/veterinary , Bordetella bronchiseptica/pathogenicity , Porcine Reproductive and Respiratory Syndrome/pathology , Porcine respiratory and reproductive syndrome virus/pathogenicity , Agglutination Tests/veterinary , Animals , Antibodies, Bacterial/blood , Antibodies, Viral/blood , Body Temperature , Body Weight , Bordetella Infections/blood , Bordetella Infections/complications , Bordetella Infections/pathology , Bronchoalveolar Lavage/veterinary , Bronchoalveolar Lavage Fluid/virology , Colony Count, Microbial , Cough/veterinary , Enzyme-Linked Immunosorbent Assay/veterinary , Lung/microbiology , Lung/pathology , Lung/virology , Porcine Reproductive and Respiratory Syndrome/blood , Porcine Reproductive and Respiratory Syndrome/virology , Random Allocation , Swine , Trachea/microbiology , Trachea/pathology , Trachea/virology , Turbinates/microbiology , Turbinates/pathology , Turbinates/virology
16.
Vet Microbiol ; 73(1): 1-12, 2000 Apr 04.
Article in English | MEDLINE | ID: mdl-10731613

ABSTRACT

Bordetella bronchiseptica causes respiratory disease in swine, yet there are no studies examining the interaction of B. bronchiseptica with swine alveolar macrophages. A swine isolate of B. bronchiseptica was able to adhere to, and survive intracellularly in, swine alveolar macrophages, but the relative ability of the bacteria to accomplish these functions was dependent on its phenotypic phase and culture conditions. More bacteria were observed extracellularly as well as intracellularly by immunofluorescent staining when B. bronchiseptica was cultured at 23 degrees C as compared to 37 degrees C. However, more bacteria cultured at 37 degrees C were found surviving intracellularly after the macrophages were cultured with polymyxin B to kill extracellular bacteria. Similar results were seen in experiments performed with an isogenic Bvg(-) phase-locked mutant of B. bronchiseptica cultured at 37 or 23 degrees C, indicating that another temperature dependent mechanism in addition to bvg may play a role in adhesion and intracellular survival. B. bronchiseptica was cytotoxic for swine alveolar macrophages in the Bvg(+) phase only. The cytotoxicity of B. bronchiseptica for alveolar macrophages, and its ability to survive phagocytosis, are no doubt important to escape from immune clearance mechanisms and establish infection, and could leave the host susceptible to secondary respiratory pathogens.


Subject(s)
Bacterial Proteins/genetics , Bordetella Infections/veterinary , Bordetella bronchiseptica/pathogenicity , Macrophages, Alveolar/microbiology , Swine Diseases/microbiology , Transcription Factors/genetics , Animals , Antibodies, Bacterial/biosynthesis , Bacterial Adhesion/immunology , Bacterial Outer Membrane Proteins/immunology , Benzenesulfonates/chemistry , Bordetella Infections/immunology , Bordetella Infections/microbiology , Bordetella bronchiseptica/genetics , Bordetella bronchiseptica/immunology , Cells, Cultured , Cytochalasin D/chemistry , Fluorescent Dyes/chemistry , Gene Expression Regulation , Immunoblotting/veterinary , Macrophages, Alveolar/immunology , Mutation , Nucleic Acid Synthesis Inhibitors/chemistry , Polymyxin B/chemistry , Rabbits , Swine , Swine Diseases/immunology , Temperature , Virulence
18.
Am J Vet Res ; 60(8): 1022-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10451216

ABSTRACT

OBJECTIVES: To determine whether intrauterine inoculation of porcine reproductive and respiratory syndrome virus (PRRSV) interferes with conception and whether exposure to one strain of PRRSV provides protection against challenge-exposure (CE) with homologous or heterologous strains of PRRSV. ANIMALS: 40 gilts. PROCEDURE: Gilts were inoculated by intrauterine administration of a PRRSV isolate (NADC-8) at breeding. Inoculated and noninoculated gilts were exposed oronasally to homologous (NADC-8) or heterologous (European isolate) PRRSV during late gestation. Specimens from gilts and fetuses were tested against CE virus. Lack of virus in gilts indicated protective immunity for the dam, in fetuses indicated protection of gilt from reproductive losses, and in both groups indicated complete protection. RESULTS: In the homologous CE group, interval from inoculation to CE ranged from 90 to 205 days, and protection was complete. In the heterologous CE group, interval from inoculation to CE ranged from 90 to 170 days, and protection was incomplete. The CE virus was detected in gilts necropsied 134 to 170 days after CE and in a litter necropsied 170 days after CE. CONCLUSIONS: Homologous protection can be induced in gilts by exposure to live PRRSV. Heterologous protection from reproductive losses can be induced in gilts by exposure to live PRRSV; however, this protection is incomplete and may have a shorter duration than homologous protection. CLINICAL RELEVANCE: Exposure of swine to enzootic PRRSV will provide protection against homologous PRRSV-induced reproductive losses. Extent and duration of protection against heterologous PRRSV may be variable and dependent on antigenic relatedness of the virus strains used for inoculation and CE.


Subject(s)
Immunization/veterinary , Porcine Reproductive and Respiratory Syndrome/immunology , Porcine Reproductive and Respiratory Syndrome/prevention & control , Porcine respiratory and reproductive syndrome virus/immunology , Animals , Antibody Formation/immunology , Antigens, Viral/immunology , Breeding , Bronchoalveolar Lavage Fluid/virology , Cytopathogenic Effect, Viral , Female , Fetal Blood/virology , Immunization/methods , Male , Pregnancy , Swine
19.
FEMS Microbiol Lett ; 174(2): 225-9, 1999 May 15.
Article in English | MEDLINE | ID: mdl-10339812

ABSTRACT

The ability of nonmodulated Bvg+ phase cultures, temperature modulated Bvg- phase cultures, and a Bvg- phase-locked mutant of Bordetella bronchiseptica to colonize the rat upper respiratory tract was investigated. Initially, greater numbers of the temperature modulated Bvg- phase bacteria adhered to the nasal cavity of the rats. The temperature modulated Bvg- phase bacteria appeared to be quickly cleared to levels lower than the Bvg+ phase bacteria by 4 h after inoculation and stayed lower until 48 h after inoculation when colonization levels were equal to the Bvg+ phase bacteria. The level of colonization with the Bvg- phase-locked mutant of B. bronchiseptica was lower than both the nonmodulated Bvg+ phase and temperature modulated Bvg- phase cultures and declined over time during the experiment. These findings suggest that there may be increased adherence from an environmental phase to ensure bacteria survive initial clearance mechanisms until the switch to the Bvg+ phase occurs.


Subject(s)
Bordetella bronchiseptica/growth & development , Bordetella bronchiseptica/pathogenicity , Nasal Cavity/microbiology , Animals , Bacterial Adhesion , Bacterial Proteins/genetics , Cell Line , Macrophages/microbiology , Mice , Rats , Rats, Sprague-Dawley , Temperature , Virulence
20.
Laryngorhinootologie ; 77(12): 715-8, 1998 Dec.
Article in German | MEDLINE | ID: mdl-10036675

ABSTRACT

BACKGROUND: Factor XIII is known to play an important role in wound healing. In patients with head and neck carcinomas there is an accumulation of risk factors for factor XIII deficiency such as chronic liver disease, extensive tissue lesions, and high intraoperative blood loss. METHOD: Serum levels of factor XIII in 22 patients who had undergone tumor surgery for head and neck carcinoma were measured preoperatively and daily up to 1 week following surgery. Factor XIII was measured with the Berichrome assay as part of our routine laboratory studies. The results were correlated with preoperative pseudocholinesterase (PChe). Factor XIII was substituted for 3 days in 8 patients with persistent wound healing problems that did not improve after two weeks of conservative treatment. RESULTS: We found that PChe levels are a predictor for the development of factor XIII levels during this period. In patients (n = 14) with normal PChe, factor XIII levels reached 86% of the preoperative values 1 week after operation (group 1). In patients (n = 8) with low PChe, the levels reached only 65% (group 2). The rate of wound healing problems was higher in group 2 (6/8) than in group 1 (2/14). In 6 patients treated with factor XIII, the wounds healed within 3 to 7 days. In two cases revision operation was necessary. CONCLUSION: We conclude that the therapy with factor XIII may be successful in patients with wound healing problems. Further studies will be necessary to find out whether prophylactic substitution of factor XIII in patients with low preoperative pseudocholinesterase levels is useful.


Subject(s)
Carcinoma, Squamous Cell/surgery , Factor XIII/administration & dosage , Otorhinolaryngologic Neoplasms/surgery , Postoperative Complications/therapy , Wound Healing/drug effects , Adult , Aged , Butyrylcholinesterase/blood , Carcinoma, Squamous Cell/pathology , Factor XIII/physiology , Factor XIII Deficiency/enzymology , Factor XIII Deficiency/therapy , Female , Humans , Male , Middle Aged , Neck Dissection , Neoplasm Staging , Otorhinolaryngologic Neoplasms/pathology , Postoperative Complications/enzymology , Prognosis , Reoperation , Treatment Outcome , Wound Healing/physiology
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