Increased systemic levels of inflammatory mediators following one-stage full-mouth scaling and root planing.

BACKGROUND AND OBJECTIVE: Full-mouth scaling and root planing (FM-SRP) acts as a potent inflammatory stimulus immediately after treatment; however, systemic inflammation typically improves in the long term. The contribution of FM-SRP to systemic biological and acute-phase responses is largely unknown. The purpose of this prospective intervention study was to assess the systemic and local biological responses after FM-SRP. MATERIAL AND METHODS: Thirty-one patients with generalized moderate-to-severe chronic periodontitis received 1-stage FM-SRP. Measurement of clinical parameters and body temperature as well as collection of subgingival plaque, peripheral blood and gingival crevicular fluid was performed before and after treatment 2 or 3 times. Quantification of periodontopathic bacteria in the sulcus and measurement of corresponding serum IgG titers were performed. Systemic and local inflammatory markers such as endotoxin, high-sensitive C-reactive protein (hs-CRP) and 6 inflammatory cytokines were assessed using high-sensitivity assays. RESULTS: Compared to baseline values, FM-SRP resulted in a substantial improvement in clinical parameters (P < .05), lower bacterial counts (P < .01) and a significant decrease of IgG titers against Porphyromonas gingivalis (P < .001) 6 weeks after treatment. Comparing baseline parameters to those at 1 day post-treatment, there was a statistically significant elevation in body temperature (P = .007). In addition, a 5-fold increase in hs-CRP (P < .001), a remarkable increase in interferon-γ (P < .001) and a slight increase in interleukin (IL)-12p70 (P = .001) were detected in serum samples. In the gingival crevicular fluid, marked increases in hs-CRP (P < .001), IL-5 (P = .001), IL-6, IL-12p70 and tumor necrosis factor-α (P < .001 for the latter 3 markers) were noted 1 day after treatment. Endotoxin levels were below measurable limits for most time points. CONCLUSION: FM-SRP resulted in clinical and microbiological improvement 6 weeks post-treatment, but produced a moderate systemic acute-phase response including elevated inflammatory mediators 1 day post-treatment.

Assessing the progression of chronic periodontitis using subgingival pathogen levels: a 24-month prospective multicenter cohort study.

BACKGROUND: The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients. METHODS: This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis. RESULTS: Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708). CONCLUSIONS: The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24-mo prospective multicenter cohort study.

BACKGROUND AND OBJECTIVE: A diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability. MATERIAL AND METHODS: A total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test. RESULTS: Of the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790). CONCLUSIONS: It is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

Altered gene expression in leukocyte transendothelial migration and cell communication pathways in periodontitis-affected gingival tissues.

BACKGROUND AND OBJECTIVE: Gene expression is related to the pathogenesis of periodontitis and plays a crucial role in local tissue destruction and disease susceptibility. The aims of the present study were to identify the expression of specific genes and biological pathways in periodontitis-affected gingival tissue using microarray and quantitative real-time RT-PCR analyses. MATERIAL AND METHODS: Healthy and periodontitis-affected gingival tissues were taken from three patients with severe chronic periodontitis. Total RNAs from six gingival tissue samples were used for microarray analyses. Data-mining analyses, such as comparisons, gene ontology and pathway analyses, were performed and biological pathways with a significant role in periodontitis were identified. In addition, quantitative real-time RT-PCR analysis was performed on samples obtained from 14 patients with chronic periodontitis and from 14 healthy individuals in order to confirm the results of the pathway analysis. RESULTS: Comparison analyses found 15 up-regulated and 13 down-regulated genes (all of which showed a change of more than twofold in expression levels) in periodontitis-affected gingival tissues. Pathway analysis identified 15 up-regulated biological pathways, including leukocyte transendothelial migration, and five down-regulated pathways, including cell communication. Quantitative real-time RT-PCR verified that five genes in the leukocyte transendothelial migration pathway were significantly up-regulated, and four genes in the cell communication pathway were significantly down-regulated, which was consistent with pathway analysis. CONCLUSION: We identified up-regulated genes (ITGB-2, MMP-2, CXCL-12, CXCR-4 and Rac-2) and down-regulated genes (connexin, DSG-1, DSC-1 and nestin) in periodontitis-affected gingival tissues; these genes may be related to the stimulation of leukocyte transendothelial migration and to the the impairment of cell-to-cell communication in periodontitis.

Polymorphisms in the promoter region of the porcine antiviral MX1 and MX2 genes.

The porcine MX1 and MX2 promoters were characterized in this study. Sequencing of the 332-bp MX1 promoter region identified 15 substitutions and insertions at three positions in 21 pigs from 15 breeds, in which nine genotypes were classified. Among the nine genotypes, no statistically significant differences in the promoter activities were observed after interferon (IFN-alpha 2b) treatment of transiently transfected cells containing constructs with luciferase reporter plasmids. The 341-bp MX2 promoter region contained regulatory sequences for ISRE, GC box, Sp1 and AP-1, as well as a TATA box. Nucleotide sequences of the MX2 promoter region revealed four substitutions and one deletion, in which six genotypes were classified. Among the six genotypes, a statistically significant difference (P < 0.05) in MX2 promoter activities after IFN-alpha 2b treatment was detected in transiently transfected cells.

Expression of neprilysin in periodontitis-affected gingival tissues.

OBJECTIVE: Although the pathogeneses of Alzheimer's disease (AD) and periodontal diseases have overlapping features, including ageing and chronic inflammation, the association between AD and periodontitis remains unclear. To explore the pathogenesis of periodontitis, a comprehensive gene expression/transcriptome analysis in periodontitis-affected gingival tissues found that the AD pathway was significantly up-regulated in periodontitis-affected gingival tissues. AD-related genes, amyloid beta precursor protein (APP), interleukin-1 beta and compliment 1QA, were significantly elevated in periodontitis. In the present study, balance between mRNA expression of APP and a potent amyloid degradation enzyme, neprilysin (NEP), as well as protein localisation of APP and NEP were analysed. DESIGN: Eighteen periodontitis-affected and 18 clinically healthy control gingival tissues were taken from patients with severe chronic periodontitis or undergoing tooth extraction. Total RNA was purified and used for quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR). The localisation of APP and NEP was analysed by immunohistochemistry (IHC). RESULTS: Both APP and NEP genes were up-regulated in periodontitis-affected gingival tissues. APP-expressing macrophages and NEP-expressing neutrophils and fibroblasts, reflecting inflammatory stages, were detected in inflamed gingival tissues by IHC. CONCLUSION: The up-regulation of APP and NEP mRNA levels in periodontitis-affected gingival tissues compared with healthy controls was confirmed by qRT-PCR analyses. Since NEP is one of the primary enzymes that degrades amyloid beta, increased NEP mRNA levels in periodontitis may act as an inhibitor of amyloid beta accumulation in gingival tissues, balancing increased APP mRNA expression. However, NEP has several effects including degradation of vasoactive substances; therefore, further sresearch is needed.

Mechanism of impaired left ventricular wall motion in the diabetic heart without coronary artery disease.

OBJECTIVE: To elucidate whether impairment of the myocardial free fatty acid (FFA) metabolism and small vessel abnormalities in the myocardium are etiologic or contributory factors of myocardial dysfunction in patients with NIDDM without any significant coronary artery disease. RESEARCH DESIGN AND METHODS: We performed myocardial imaging with 123I-labeled beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP), a branched analog of FFA, and dipyridamole-infusion 201thallium scintigraphy (Dip) in nine patients who demonstrated left ventricular wall motion abnormalities without any significant coronary artery disease and in fifteen control cases. As an index of myocardial FFA metabolism, the heart-to-mediastinum count ratio (H/M) of BMIPP was calculated from the mean count in the regions of interest at the heart and the upper mediastinum. RESULTS: Nine patients with reduced wall motion documented by left ventriculography (LVG), (hypokinetic group) demonstrated significantly lower BMIPP uptake (2.1 +/- 0.2, mean +/- SD) than fifteen patients with normal wall motion (normokinetic group) (2.3 +/- 0.2, P < 0.05). Regional ventricular wall motion observed by LVG, regional BMIPP uptake, and regional redistribution phenomenon (RD) were evaluated for five regions of the left ventricle: anterior, septal, apical, lateral, and inferoposterior regions. Wall motion was abnormal in 24 out of 120 regions. Regional BMIPP uptake was reduced in 47 regions. RD in Dip was observed in 23 regions. In regional analysis, the existence of defect in the BMIPP image showed significant correlation with wall motion abnormality (P < 0.01), but there was no significant relationship between the RD in Dip and regional wall motion abnormality (P = 0.16). Myocardial biopsy specimens obtained from the right ventricle of 20 patients showed no pathologic changes, with the exception of two patients. CONCLUSIONS: Our findings suggest that impairment of myocardial FFA metabolism rather than small vessel abnormalities in the myocardium is responsible for modest left ventricular dysfunction in patients with diabetes.

Evaluation of a novel immunochromatographic device for rapid and accurate clinical detection of Porphyromonas gingivalis in subgingival plaque.

UNLABELLED: An important goal for the improved diagnosis and management of infectious and inflammatory diseases, such as periodontitis, is the development of rapid and accurate technologies for the decentralized detection of bacterial pathogens. The aim of this prospective multicenter study was to evaluate the clinical use of a novel immunochromatographic device with monoclonal antibodies for the rapid point-of-care detection and semi-quantification of Porphyromonas gingivalis in subgingival plaque. Sixty-three patients with chronic periodontitis and 28 periodontally healthy volunteers were subjected to clinical and microbiological examinations. Subgingival plaque samples were analyzed for the presence of P. gingivalis using a novel immunochromatography based device DK13-PG-001, designed to detect the 40k-outer membrane protein of P. gingivalis, and compared with a PCR-Invader method. In the periodontitis group, a significant strong positive correlation in detection results was found between the test device score and the PCR-Invader method (Spearman rank correlation, r=0.737, p<0.0001). The sensitivity, specificity, and positive and negative predictive values of the test device were 96.2%, 91.8%, 90.4% and 96.7%, respectively. The detection threshold of the test device was determined to be approximately 10(4) (per two paper points). There were significant differences in the bacterial counts by the PCR-Invader method among groups with different ranges of device scores. With a cut-off value of ≥0.25 in device score, none of periodontally healthy volunteers were tested positive for the subgingival presence of P. gingivalis, whereas 76% (n=48) of periodontitis subjects were tested positive. There was a significant positive correlation between device scores for P. gingivalis and periodontal parameters including probing pocket depth and clinical attachment level (r=0.317 and 0.281, respectively, p<0.01). The results suggested that the DK13-PG-001 device kit can be effectively used for rapid, chair-side detection and semi-quantification of P. gingivalis in subgingival plaque. TRIAL REGISTRATION: UMIN Clinical Trials Registry (UMIN-CTR) UMIN000011943.

Quantification of systolic count increase in technetium-99m-MIBI gated myocardial SPECT.

UNLABELLED: This study was performed to clarify the validity of quantification of myocardial wall thickening by the count increase method using electrocardiography (ECG)-gated SPECT. METHODS: We performed a phantom study to examine the quantification of this method and to clarify the relationship between the changes of relative counts and objective size (such as myocardial wall) under various conditions. In addition, in volunteers, the percent count increase (%CI) was analyzed in left ventricular segments based on circumferential profile curve analysis by ECG-gated SPECT with 99mTc-MIBI (methoxyisobutyl-isonitrile), and it was compared with the regional systolic wall thickness (%Th) assessed by echocardiography during low-dose dobutamine infusion. RESULTS: In our phantom study, the relative count changes were correlated linearly with the object size only within less than 20 mm. Recovery coefficient curves were influenced by acquisition parameters such as type of collimator, diameter of camera rotation, counts and photon scattering. In ECG-gated SPECT, the %CI value was increased gradually at each stage after dobutamine infusion, in relation to the increase of the %Th seen on echocardiography, although there are significant large deviations between these two parameters. CONCLUSIONS: In this study, quantitative analysis based on the %CI in ECG-gated SPECT may underestimate regional wall thickening. These data should be considered in the evaluation of the %CI as an index of myocardial function.

Abnormal iodine-123-MIBG images in healthy volunteers.

We have encountered two healthy volunteers with significant reductions of myocardial [123I]MIBG (metaiodobenzylguanidine) uptake and rapid clearance. In one of these subjects (a 31-yr-old man), we performed additional examinations to clarify the mechanism of the abnormal myocardial MIBG uptake. There was no abnormality on orthostatic test, maximal exercise test (bicycle ergometer) or in plasma norepinephrine concentration. Nevertheless, power spectral analysis (PSA) of heart rate variability revealed that the percent low frequency component (%LF), an index of sympathetic nerve activity, was increased. Furthermore, [123I]MIBG scintigraphy after oral administration of an alpha 2 agonist (guanabenz acetate; 4 mg) demonstrated that myocardial uptake and clearance of MIBG returned to normal, as did the %LF. These results suggest that reduced uptake and rapid clearance of myocardial MIBG in this subject was strongly related to the increased release of norepinephrine from sympathetic nerve terminals due to augmented sympathetic activity. This subject illustrated that unsuspected, subclinical variants of normal or abnormal sympathetic functions may pose a diagnostic pitfall in interpretating myocardial MIBG images.

Myocardial iodine-123-metaiodobenzylguanidine images and autonomic nerve activity in normal subjects.

UNLABELLED: We studied the relationship between myocardial [123I]metaiodobenzylguanidine (MIBG) uptake and autonomic nerve activity in normal subjects. METHODS: MIBG scintigraphy and power spectral analysis (PSA) of heart rate variability were performed simultaneously in 15 normal subjects. Anterior planar images and SPECT images were taken at five and two points after the injection of [123I]MIBG, respectively. In 10 of 15 subjects, 201TI myocardial SPECT was performed immediately after MIBG scintigraphy. RESULTS: The heart/upper mediastinum MIBG uptake ratio in the planar image obtained at 240 min (r = 0.64, p < 0.01) and the washout rate of MIBG in the heart between 15 min and 240 min (r = 0.51, p < 0.05) showed significant correlation with the percentage of low frequency component of PSA (percent LF), an index of sympathetic nerve activity. Regional MIBG uptake in the inferior wall normalized by individual maximal uptake among all pixels was significantly correlated with the high frequency component of PSA, an index of parasympathetic nerve activity (r = -0.58, p < 0.05) and with mean R-R interval in a resting ECG (r = -0.82, p < 0.001) but did not correlate with percent LF, percent uptake of 201TI in the inferior wall or the liver/heart uptake ratio. CONCLUSION: These results indicate that myocardial MIBG uptake correlates with sympathetic nerve activity in normal subjects. Our data indicate that heterogeneous MIBG distribution in the left ventricle is a physiologic rather than artifactual phenomenon and may be related to vagal tone rather than sympathetic nerve activity.

Structure of the pig sterol 14alpha-demethylase (CYP51) gene and its expression in the testis and other tissues.

A cDNA coding sterol 14alpha-demethylase (CYP51), which was isolated from a pig liver cDNA, contained a 1,512 bp open reading frame and a 758 bp 3'-untranslated region. The deduced amino acid sequence was 94% identical to those of human and rat CYP51s. The pig CYP51 gene spanned about 21 kb and was divided into 10 exons. The sites of exon-intron junctions were completely identical to those in the human and rat CYP51 genes. Five GC boxes, but not a TATA box, were found in the 5'-flanking region of the gene, and cyclic AMP and sterol responsive elements were also found in this region. The main transcription start site determined with the 5'-RACE method with poly(A)(+) RNA from the liver and testis was located at 143 nucleotides upstream from the initiation codon in both tissues. Northern blot analysis revealed that an approximately 2.4 kb mRNA, which is produced through the use of a polyadenylation signal (AATAAA) located at 740 nucleotides downstream of the stop codon, was expressed in all the tissues examined in pigs: The mRNA levels were much higher in the liver and testis than in the kidney, lung, and epididymis. Furthermore, after the onset of spermatogenesis, a smaller size of mRNA (about 1.8 kb) was found in the testis but not in the epididymis. The 1.8 kb mRNA was produced through the use of an unusual polyadenylation signal (AAGAAA) located at 28 nucleotides downstream of the stop codon.

Proteolytic zymograms of Staphylococcus hyicus subsp. hyicus isolated from pigs, chickens and cows.

The extracellular proteases of Staphylococcus hyicus subsp. hyicus were assayed by a zymogram showing caseinolysis and gelatinolysis. Four bands were associated with caseinolysis or with gelatinolysis. The patterns shown by strains isolated from pigs, chickens and cows were compared; isolates from pigs differed from those isolated from chickens or cows but strains isolated from diseased and healthy pigs could not be differentiated.

Myocardial metabolism of 123I-BMIPP in patients with hypertrophic cardiomyopathy: assessment by radial long-axis SPET.

To elucidate the metabolism of free fatty acid in the myocardium of hypertrophic cardiomyopathy (HCM), SPET was performed with 123I-15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP), an analogue of free fatty acid, and with 201Tl in nine patients with HCM and eight healthy volunteers who acted as controls. For quantitative analysis of the apical area, a radial long-axis tomogram was reconstructed every 6 degrees after short-axis tomography. The relative regional uptake (RRU, %) in each segment was obtained by normalizing to the maximal value among all segments. The 3-h washout rate was calculated both for BMIPP and for 201Tl. The ratio of the RRU of BMIPP to that of 201Tl was significantly lower in the apical and antero-septal regions compared with other walls (P < 0.01) in the patients with HCM, whereas uptake of both BMIPP and 201Tl in the controls was homogeneous and there was a significant correlation between them. The coefficient of variation (CV) in all segments in the HCM patients was significantly higher (P < 0.01) than that of the controls both BMIPP and 201Tl, indicating inhomogeneous uptake of BMIPP in the HCM patients. The washout rate of BMIPP over 3 h was significantly higher in the patients with HCM (mean +/- S.D. 26.3 +/- 7.3%) than the controls (18.3 +/- 7.5%, P < 0.05). The ratio of segmental washout rate of BMIPP to that of 201Tl in the HCM patients was increased, especially in the septum and apex.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical value of lung uptake of iodine-123 metaiodobenzylguanidine (MIBG), a myocardial sympathetic nerve imaging agent, in patients with chronic heart failure.

This study investigated the clinical value of I-123 MIBG pulmonary accumulation and washout in patients with chronic heart failure (CHF). Nineteen patients with CHF and 15 normal volunteers (NL) were included. The uptake ratio of heart to mediastinum (H/M), that of lung fields to mediastinum (L/M), and washout rate (WR) of the heart and lung fields were calculated in anterior planar images and compared with results of echocardiography and cardiac catheterization. In the CHF group, the lung uptake in delayed images increased and lung WR was decreased, suggesting pulmonary endothelial lesions. Furthermore, there was a negative correlation between right and left lung WR and pulmonary arterial diastolic pressure (PA(D)) and pulmonary arterial systolic pressure (PA(s)) in the CHF group. Since the WR of MIBG reflected PA, it may be used as an index of severity of cardiac dysfunction.

Prognosis of hypertrophic cardiomyopathy: assessment by 123I-BMIPP (beta-methyl-p-(123I)iodophenyl pentadecanoic acid) myocardial single photon emission computed tomography.

123I-BMIPP (beta-methyl-iodophenyl pentadecanoic acid) has shown unique properties for potential use in assessing myocardial metabolism. Previous basic and clinical studies demonstrated that the disturbances of myocardial metabolism precede the occurrence of myocardial perfusion abnormalities by using 201Tl in hypertrophic myocardium. The present study was therefore undertaken to determine whether or not 123I-BMIPP myocardial SPECT is useful in predicting the prognosis of hypertrophic cardiomyopathy (HCM) in 65 patients in 6 facilities. There were 33 patients with non-obstructive HCM, 12 with obstructive HCM, 12 with apical HCM and 8 with dilated-phase HCM. Fasted patients at rest received an intravenous injection of 111 MBq of 123I-BMIPP. Twenty to thirty minutes later, myocardial SPECT was carried out. The BMIPP severity score (BMIPP SS) was evaluated semiquantitatively by using representative short axial SPECT images. We followed up the incidence of cardiac events for a mean period of 3.0 +/- 0.6 years. Cardiac events occurred in 13 patients. Of these, 11 developed heart failure and 6 died (4 from heart failure and 2 from sudden death). The BMIPP SS in the dilated-phase HCM was significantly lower than that for the nonsurvivors. The BMIPP SS was particularly high in patients with fatal heart failure. Furthermore, there was a close negative correlation between the BMIPP SS and percent fractional shortening measured by echocardiography (r = -0.49). Finally, the mortality over the three years increased according to the extent of the BMIPP SS. In conclusion, these results indicate that BMIPP SS is useful in evaluating the severity of HCM. We conclude that 123I-BMIPP is a valuable metabolic tracer in predicting the outcome of HCM.

Migration behavior of alkylphenols, bisphenol A and bisphenol S studied by capillary electrophoresis using sulfated beta-cyclodextrin.

An application of capillary electrophoresis (CE) using sulfated beta-cyclodextrin (SCD) has been investigated for separating alkylphenols with different chain lengths, as well as bisphenol A and bisphenol S. In the absence of SCD in running buffer, all the phenols migrated at the same velocity as the electroosmotic flow (EOF), whereas the addition of SCD effectively led to the baseline separation of alkylphenols on the basis of the difference in the abilities to bind into the hydrophobic cavity of CD. The host-guest binding constants between analyte phenols and SCD were evaluated from Benesi-Hildebrand plots of the data obtained by two independent methods, CE and UV-visible measurements, demonstrating that the greater the hydrophobicity of the phenols, the larger the binding constants. The effects of organic solvents on the resolution for alkylphenols and bisphenols were also examined. This system using SCD was effective for the separation of 4-octylphenol and 4-nonylphenol isomers having longer alkyl chains.

Effect of physical defenses of the respiratory tract on the development of pneumonia in pigs inoculated endobronchially with Actinobacillus pleuropneumoniae.

Seven pigs inoculated endobronchially with Actinobacillus pleuropneumoniae (App) serotype 1 developed acute and subacute necrotizing pleuropneumonia. When treated with high doses of atropine (0.25 mg per kg) and/or xylocaine spray using a bronchoscope, which suppressed mucus secretion and ciliary activity, the pigs showed severe pleuropneumonia and 2 treated pigs died within 36 hr after inoculating 320 colony forming units (CFU)/2ml of App serotype 1. Histopathologically, their lungs had alveolar and interlobular edema and intravascular fibrinous thrombosis. In the surviving pigs, the lymph nodes had App antigens in the germinal centers corresponding closely with activated follicular dendritic cells and increased in the number of IgG- and IgM-containing cells. The bacterial antigens were also observed as small sized granules in the cytoplasm of bronchoalveolar macrophages. These findings suggest that the attachment of App to the mucosal surface may be crucial in the development of pneumonic lesions.

Pathologic observations of pigs intranasally inoculated with serovar 1, 4 and 5 of Haemophilus parasuis using immunoperoxidase method.

Nineteen, 7- to 13-week-old pigs were inoculated intranasally with different strains of Haemophilus parasuis (serovar 1, 4 and 5), and the pathological lesions induced by each strain were compared. Eleven of thirteen pigs inoculated with either strain Nagasaki (serovar 5) or No. 4 (serovar 1) died between days 1 to 6 after inoculation, and had septicemic lesions, meningitis, or polyserositis. One of six pigs inoculated with strain SW124 (serovar 4) died with polyserositis, another one recovered after illness, and the remaining four pigs remained in good health. Five of the septicemic pigs had thrombi at many organs. Endotoxin was detected in the plasma of 10 pigs in the acute stage of infection. Using the immunoperoxidase technique, H. parasuis antigen was detected in lesions of infected pigs. In the serosal lesions the bacterial antigen was found mainly in the cytoplasm of infiltrating neutrophils and macrophages and appeared as degenerated bacteria and/or lytic bacterial material in dilated phagosomes. Many of the bacteria in the blood vessels of pigs with septicemic lesions were also degenerated. Although H. parasuis was reisolated from nasal secretions of infected pigs, the bacterial antigen could not be detected in the nasal cavities of these pigs. No lesions were observed in the parenchyma of the lung. However, H. parasuis antigen was detected in the tonsil of infected pigs.

Pathogenicity of Haemophilus parasuis serovars 4 and 5 in contact-exposed pigs.

The pathogenicities of Haemophilus parasuis strains SW124 (serovar 4) and Nagasaki (serovar 5) were examined by contact-exposure of specific pathogen-free (SPF) pigs. Ten pigs were divided into three groups. Two of four pigs in the first group were inoculated intranasally (IN) with 2 x 10(8) CFU of strain SW124, and the other two pigs were mingled with these IN-exposed ones. All the four pigs were subclinically infected in this group. The four pigs of the second group were likewise exposed to strain Nagasaki (two IN-inoculated pigs with 3 x 10(8) CFU of strain Nagasaki). All four pigs in this group died of Glässer's disease. Two pigs kept as controls showed neither abnormality nor positive H. parasuis isolation.