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PubMed2006

Ventricular peritoneal shunt infection resulting from group B streptococcus.

OBJECTIVE: To report, to our knowledge, the first case of a ventricular peritoneal shunt infection by group B streptococcus occurring in infancy. DESIGN: Descriptive case report. SETTING: Neonatal intensive care unit in a tertiary referral military hospital. PATIENT: A 3-month-old, former preterm infant with a case of postoperative ventricular peritoneal shunt infection by group B streptococcus occurring in infancy. INTERVENTIONS: The infant's shunt infection was treated with a prolonged course of antibiotics, shunt removal, and eventual shunt replacement. He developed a persistently enlarging third ventricular region cyst, which ultimately required endoscopic surgical fenestration. MEASUREMENTS AND MAIN RESULTS: Currently, at 25 months of age, the patient has some moderate developmental delays but is otherwise healthy and making progress with no evidence of any recurrent infection CONCLUSIONS: Group B streptococcus should be considered as a potential pathogen in ventricular peritoneal shunt infections in infants even outside of the immediate neonatal period. Providers caring for infants should be especially cognizant of the potential risk for nosocomial infections in former premature neonates, especially following high-risk surgical procedures. Prompt recognition of ventricular peritoneal shunt infections and management to include early shunt removal and appropriate antibiotic coverage are recommended in an effort to optimize outcome.

Cross Infection↗
PubMed2005

Cytotoxicity potential and genotypic characterization of Escherichia coli isolates from environmental and food sources.

The presence of Escherichia coli isolates in the environment is a potential source of contamination of food and water supplies. Moreover, these isolates may harbor virulence genes that can be a source of new forms of pathogenic strains. Here, using multiplex PCR, we examined the presence of virulence gene markers (stx1, stx2, eaeA, hlyA) in 1,698 environmental isolates of E. coli and 81 isolates from food and clinical sources. The PCR analysis showed that approximately 5% (79 of 1,698) of the total environmental isolates and 96% (79 of 81) of the food and clinical isolates were positive for at least one of the genes. Of the food and clinical isolates, 84% (68 of 81 isolates) were positive for all four genes. Of the subset of environmental isolates chosen for further analysis, 16% (13 of 79 isolates) were positive for stx2 and 84% (66 of 79 isolates) were positive for eaeA; 16 of the latter strains were also positive for hlyA. The pathogenic potentials of 174 isolates (81 isolates from food and clinical sources and 93 isolates from environmental sources) were tested by using a cytotoxicity assay based on lactate dehydrogenase release from Vero cells. In general, 97% (79 of 81) of the food and clinical isolates and 41% (39 of 93) of the environmental isolates exhibited positive cytotoxicity. High cytotoxicity values correlated to the presence of stx genes. The majority of hly-positive but stx-negative environmental isolates also exhibited a certain degree of cytotoxicity. Isolates were also tested for sorbitol utilization and were genotyped by ribotyping and by repetitive extragenic palindromic PCR (REP-PCR) as potential means of quickly identifying virulent strains from the environment, but none of these methods could be used to distinguish cytotoxic environmental isolates. Only 31% of the isolates were negative for sorbitol fermentation, and none of the isolates had common ribotypes or REP-PCR fingerprints. This study suggests that overall higher cytotoxicity values correlated with the production of stx genes, and the majority of hly-positive but stx-negative environmental isolates also exhibited a certain degree of cytotoxicity. This study demonstrated that there is widespread distribution of potentially virulent E. coli strains in the environment that may be a cause of concern for human health.

Animals↗
PubMed1997

Comparative analysis of immunoglobulin A1 protease activity among bacteria representing different genera, species, and strains.

Immunoglobulin A1 (IgA1) proteases cleaving human IgA1 in the hinge region are produced constitutively by a number of pathogens, including Haemophilus influenzae, Neisseria meningitidis, Neisseria gonorrhoeae, and Streptococcus pneumoniae, as well as by some members of the resident oropharyngeal flora. Whereas IgA1 proteases have been shown to interfere with the functions of IgA antibodies in vitro, the exact role of these enzymes in the relationship of bacteria to a human host capable of responding with enzyme-neutralizing antibodies is not clear. Conceivably, the role of IgA1 proteases may depend on the quantity of IgA1 protease generated as well as on the balance between secreted and cell-associated forms of the enzyme. Therefore, we have compared levels of IgA1 protease activity in cultures of 38 bacterial strains representing different genera and species as well as strains of different pathogenic potential. Wide variation in activity generation rate was found overall and within some species. High activity was not an exclusive property of bacteria with documented pathogenicity. Almost all activity of H. influenzae, N. meningitidis, and N. gonorrhoeae strains was present in the supernatant. In contrast, large proportions of the activity in Streptococcus, Prevotella, and Capnocytophaga species was cell associated at early stationary phase, suggesting that the enzyme may play the role of a surface antigen. Partial release of cell-associated activity occurred during stationary phase. Within some taxa, the degree of activity variation correlated with degree of antigenic diversity of the enzyme as determined previously. This finding may indicate that the variation observed is of biological significance.

Bacteria↗
PubMed1996

Bacterial colonization as a potential source of nosocomial respiratory infections in two types of spirometer.

The potential risk of spirometers in the transmission of respiratory infections has not been yet established. We performed a prospective cross-sectional study to determine the rate of colonization of a water-sealed spirometer and a pneumotachograph, and the potential risk of cross-transmission of microorganisms to patients using each of these devices. Fifty four patients (aged 51 +/- 18 (mean +/- SD) yrs) were included in the study. All of them had undergone forced spirometry with bronchodilator response by means of the water-sealed spirometer (n = 36) or the pneumotachograph (n = 18). None had a clinically apparent respiratory infection at the time of the study. Routine hygiene measures for respiratory equipment were performed before the study protocol. Samples for microbiological cultures of different parts both of the water-sealed spirometer (proximal and distal tubing, bell and water-bell) and pneumotachograph (proximal and distal tubing) were taken daily before and after the usual series of lung function tests during a 5 day period. Pharyngeal swab cultures were obtained before spirometry and 7 days later in each subject. Thirty six out of a total of 40 (90%) culture samples from the water-sealed spirometer showed microbial growth compared to 4 out of 30 (13%) samples obtained from the pneumotachograph (p < 0.0001). Significant colonization of the water-sealed spirometer was apparent after the third day of the study. The microorganisms most frequently isolated were penicillium sp. (62%), Pseudomonas fluorescens (32%), and Burkholderia cepacea (48%). Distal tubing, water and water-bell were the parts of the water-sealed spirometer that showed higher colonization counts (> or = 10(4) colony-forming units (cfu).mL-1). No transmission sequence of potentially pathogenic microorganisms from equipment to patients or vice versa could be demonstrated. In summary, the water-sealed spirometer frequently became colonized by microorganisms. The potential hazard of such equipment as reservoirs of microorganisms suggests a need for the implementation of new hygiene measures for their maintenance.

Bacterial Infections↗
PubMed1983

A comparison of pathogens and contaminants based on the number of positive blood cultures in a set.

A total of 2766 positive blood cultures, from the Veterans Administration Medical Center in Oklahoma City (1961-1981) were evaluated to determine the relationship of organism, pathogenicity and number of cultures (blood culture bottles) positive. Most patients had 2-4 blood cultures drawn. Organisms which are usually considered as nonpathogenic (Bacillus, Propionibacterium) were mostly found in only one of the cultures. Whereas those microorganisms which are considered pathogenic were most often found in two or more cultures. Organisms like Staphylococcus epidermidis are the most difficult to classify because they can be either pathogenic or contaminant. If an organisms which is normally considered a nonpathogen is found in two or more cultures, it should be considered as a potential pathogen until proven otherwise.

Bacteria↗
PubMed1996

Continuing investigation and controversy regarding risk of transmission of infection via dental handpieces.

Current epidemiologic evidence indicates that infectious diseases, specifically blood-borne pathogens such as hepatitis B, hepatitis C and HIV, are not transmitted from patient to patient via dental instruments. However, ongoing laboratory investigations suggest that potential pathogens may be retained within dental handpieces, creating a theoretical risk of cross infection. Controversy regarding certain laboratory study results and the clinical implications of these studies continues. Guidelines and regulations for infection control should be rational, and based on a realistic response to a documented risk. Dental professionals should be aware of continuing research focusing on these issues.

Blood-Borne Pathogens↗
PubMedDate not supplied

Local pathogenic bacteria in allergic rhinitis: a novel concept of its pathogenesis.

BACKGROUND: It is still unclear to what extent microorganisms are involved in the pathogenesis of allergic rhinitis. OBJECTIVE: Therefore, we examined the mucosal colonization with potential pathogenic bacteria (PPB) of the nasal cavity in allergic and nonallergic subjects. METHODS: In an open prospective study of 389 office workers (297 men, mean age 42.5 years, and 92 women, mean age 36.7 years), bacterial swabs were taken selectively from both nasal cavities. Standard skin tests for various aeroallergens and negative control tests were conducted in parallel in these subjects. RESULTS: In the 389 subjects, we found positive skin tests in 58 (15%); 37 of these revealed a high level of sensitivity, whilst the other 21 persons had low to moderate levels. Ninety percent of the 58 sensitive persons had PPB in their nasal cavity while only 36% (119) of the remaining 331 subjects with negative skin tests were shown to have PPB in nasal cultures (p < 0.001). Sixty-four percent of the sensitized subjects with PPB were found to have more than 2 PPB species and a positive correlation with the intensity of the skin reaction. In contrast, only 18% (22) of the 119 nonallergic test persons with PPB had more than 1 PPB species. CONCLUSIONS: This finding of an unusually high frequency of nasal PPB in subjects with positive skin tests to aeroallergens may indicate an involvement of PPB in the pathogenesis of allergic rhinitis. Yet, further data are still lacking to support this novel concept.

Adult↗
PubMed2001

Differences in the susceptibility of American white shrimp larval substages (Litopenaeus vannamei) to four vibrio species.

The rapid expansion of commercial culture of penaeid shrimp is threatened by Vibrio diseases affecting survival and growth. These opportunistic microorganisms are considered part of the normal ecosystem of penaeid shrimp and cause diseases only under conditions that favor them over the host. Shrimp larvae show different susceptibility to these pathogenic agents. In the present work, we report on a comparative study of the susceptibility of all American white shrimp (Litopenaeus vannamei) larval substages to four potentially pathogenic Vibrio species (V. harveyi, V. parahaemolyticus, V. alginolyticus, and V. penaeicida). Strains of these bacterial species were used to infect nauplii, protozoea I-III, mysis I-III, and postlarvae 1 by immersion challenge at 10(3), 10(5), or 10(7) cfu mL(-1) for 30 min. V. alginolyticus infection had no significant effect on survival rate, compared to control, in all shrimp larvae and at all doses tested. Shrimp larvae infected with V. alginolyticus showed a high survival rate compared to other Vibrio species at the three dose levels. V. penaeicida produced a significant mortality effect (P < 0.01) in all shrimp substages and only in postlarvae 1 at low infection dose (10(3) cfu mL(-1)). V. harveyi and V. parahaemolyticus induced significant mortality rates (P < 0.01) only at high doses in shrimp larvae. In summary, shrimp larvae demonstrated an age susceptibility that depends on the Vibrio species and dose level.

Animals↗
PubMed1989

Keratinophilic fungi on sheep hairs from the West Bank of Jordan.

The mycoflora of the hair in 285 sheep from the West Bank of Jordan was analysed and the frequency of occurrence and the relative importance value for different fungal species found were calculated. Ninety six species which belong to 36 genera were isolated. Forty one of these species were either well-known agents of animal and human mycoses (Trichophyton verrucosum, T. mentagrophytes, Microsporum nanum, M. canis, and others), or have been isolated from human and animal lesions (Arthroderma cuniculi, A. curreyi, Chrysosporium tropicum, Acremonium kiliense, Aphanoascus fulvuscens, Aspergillus versicolor, Paecilomyces lilacinus, Scopulariopsis brevicaulis, and others). These pathogenic fungi comprised 75.4% of all fungi recovered from the hair of sheep. This animal seems to represent an adequate reservoir for several dermatophytes and several potentially pathogenic fungi.

Animals↗
PubMedDate not supplied

Eikenella corrodens as a cause of recurrent and persistent infections of the head and neck.

Four patients had Eikenella corrodens infections involving the head and neck in different ways. The organism is discussed as a pathogen in mixed infections and as the predominant organism in other processes. As part of the resident microflora of mucous membrane surfaces, it is an important potential pathogen in a number of otolaryngologic clinical settings. Careful microbiological culturing and susceptibility testing reveal the causative organism and guide the antibiotic therapy.

Adolescent↗
PubMed2007

The effect of genetic background on the function of Saccharomyces cerevisiae mlh1 alleles that correspond to HNPCC missense mutations.

Germline mutations in the DNA mismatch repair (MMR) gene MLH1 are associated with a large percentage of hereditary non-polyposis colorectal cancers. There are approximately 250 known human mutations in MLH1. Of these, one-third are missense variants that are often difficult to characterize with regards to pathogenicity. We analysed 28 alleles of baker's yeast MLH1 that correspond to non-truncating human mutant alleles listed in online HNPCC databases, 13 of which had not been previously studied in functional assays. Using the highly sensitive lys2::InsE-A(14) reversion rate assay, we determined the MMR proficiency conferred by each allele in the S288c strain of Saccharomyces cerevisiae. Seven alleles conferred a null phenotype for MMR and eight others showed significant MMR defects, suggesting that all 15 are likely to be pathogenic in humans. In addition, we observed a strong correlation between these results, limited results from previous functional assays and clinical data. To test whether the potential pathogenicity of certain alleles depends on the genetic background of the host, we examined the mutation rates conferred by the mlh1 alleles in a second yeast strain, SK1, which is approximately 0.7% divergent from S288c. Many alleles displayed a difference in MMR efficiency between strain backgrounds with decreasing differences as the severity of the MMR defect increased. These findings suggest that genetic background can play an important role in determining the pathogenicity of MMR alleles and may explain cases of atypical colorectal cancer inheritance.

Adaptor Proteins, Signal Transducing↗
PubMed1998

Fiberoptic bronchoscopy in coronary care unit patients: indications, safety, and clinical implications.

STUDY OBJECTIVES: To evaluate the indications, safety, therapeutic impact, and outcome of fiberoptic bronchoscopy (FOB) in coronary care unit (CCU) patients. DESIGN: Retrospective review of all CCU patients undergoing FOB during a 6-year period. SETTING: Tertiary care university hospital. RESULTS: Among 8,330 patients admitted to the CCU; 40 (0.5%) patients underwent FOB to evaluate pulmonary abnormalities, most often (78%) to appraise clinically suspected pneumonia. Thirty-five (88%) patients were intubated and 21 (53%) had acute myocardial infarction (MI) before FOB. There were two major complications (bleeding, intubation) occurring within 24 h of FOB, one of which appeared due to the procedure. No episodes of chest pain or ischemic events were recorded and no significant increase in major complications was noted in MI patients (3% vs 5%). Patients having FOB within 10 days of MI had higher survival (79%) than those undergoing FOB later (29%) (p = 0.05). Seven different bacterial pathogens were isolated in 6 (15%) patients, probably reflecting prior empiric antibiotics in 32 (80%) patients. Therapy was changed in 64% of patients in whom a potential pathogen was identified. Despite alterations in treatment, patients with clinically suspected pneumonia and any organisms isolated by FOB had greater mortality (79% vs 31%, p = 0.003) than those with sterile FOB cultures. CONCLUSION: FOB may be diagnostically useful in the evaluation of pulmonary abnormalities in selected patients with acute cardiac disease, can be performed safely, and may influence management decisions. Positive bronchoscopy cultures often influence therapy but are associated with higher mortality, suggesting a lethal effect of nosocomial pneumonia in this subset of CCU patients. The risks of FOB must be weighed with the impact of FOB results on patient outcome, and its role requires further investigation.

Adult↗
PubMedDate not supplied

Comparison of mitogens from Mycoplasma pulmonis and Mycoplasma neurolyticum.

Studies on Mycoplasma pulmonis and Mycoplasma neurolyticum mitogenesis demonstrated that macrophages are not essential for the interactions of M. neurolyticum with B lymphocytes, whereas M. pulmonis that stimulates B and T lymphocytes depends on macrophages to fully exert its mitogenic effects. Membranes of both species carry the mitogenic as well as pathogenic potentials. However, M. neurolyticum major mitogens are biochemically distinct from those of M. pulmonis. Furthermore, M. pulmonis mitogenesis is directly correlated to the mycoplasmal-induced pathogenic effects, while no such correlation could be established with M. neurolyticum. It was, therefore, concluded that M. pulmonis and M. neurolyticum differ in the biochemical and biological natures of their mitogens.

Animals↗
PubMed1996

Management of intra-abdominal infections. The case for intraoperative cultures and comprehensive broad-spectrum antibiotic coverage. The Canadian Intra-abdominal Infection Study Group.

OBJECTIVE: To test the hypothesis that comprehensive broad-spectrum empirical antimicrobial therapy is superior to limited-spectrum empirical antimicrobial therapy in intra-abdominal infections. DESIGN: Prospective, randomized, double-blinded study. SETTING: University-affiliated hospitals in Canada. PATIENTS: Two hundred thirteen patients with intra-abdominal infections and planned operative or percutaneous drainage. INTERVENTION: Limited-spectrum empirical antimicrobial therapy consisted of cefoxitin sodium, 2 g, intravenously, every 6 hours (n = 109). Comprehensive broad-spectrum empirical antimicrobial therapy consisted of a combination of imipenem and cilastatin sodium, 500 mg, intravenously, every 6 hours (n = 104). MAIN OUTCOME MEASURES: Failure to cure the intra-abdominal infection (persistence of infection or death). RESULTS: Of initial isolates, 98% were sensitive to imipenem plus cilastin sodium compared with 72% for cefoxitin. No difference was found in the failure rate between treatment groups. Among various reasons for failure (including technical), 12 of 80 patients in the limited-spectrum empirical antimicrobial therapy group had resistant organisms at a second intervention compared with 1 of 74 in the comprehensive broad-spectrum empirical antimicrobial therapy group (P < .003, chi 2). One death in the limited-spectrum empirical antimicrobial therapy group was due to autopsy-proved disseminated Pseudomonas aeruginosa (blood, peritoneum, lung, and pleural fluid) that was resistant to cefoxitin, and the other was associated with peritonitis due to cefoxitin-resistant Enterobacter cloacae. One death in the comprehensive broad-spectrum empirical antimicrobial therapy group was associated with peritonitis from Clostridium perfringens that was sensitive to imipenem plus cilastin sodium, and the other was associated with peritonitis from Pseudomonas aeruginosa that was resistant to imipenem plus cilastin sodium. CONCLUSION: Treatment failure of intra-abdominal infection may be due, in part, to the presence of resistant pathogens at the site of infection. Therefore, routine culture of these sites seems worthwhile and empirical therapy should be as comprehensive as possible and should cover all potential pathogens.

Abdomen↗
PubMed1985

Immunological and microbiological factors in the pathogenesis of atherosclerosis.

Among the several pathological events that lead to the formation of an atheromatous lesion, endothelial cell damage, smooth muscle cell proliferation, and foam cell formation, are considered as particularly significant. In this review we summarize data suggesting that immunological and microbial factors may cause, directly or indirectly, these pathological events. Binding of immunocomplexes to endothelial cells, phagocytic cells, platelets, or erythrocytes could be the starting point for a variety of circuits leading to endothelial cell cytotoxicity and to the release of a variety of mediators, including cell proliferative factors. Endothelial cell toxicity could also be induced, directly or indirectly, by endotoxin; however, the possibility that endotoxin and other microbial factors may induce abnormalities in lipid metabolism at the monocyte/macrophage level which eventually result in intracellular accumulation of cholesterol (particularly if cholesterol levels are elevated) is specially attractive as a potential pathogenic mechanism. The various pathologic pathways discussed in this review appear plausible on the basis of our current knowledge and point to the need to investigate the potential role of infectious processes, autoimmune reactions, and administration of antigenic compounds as possible risk factors for the development of atherosclerosis.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1996

Investigation of chronic diarrhoea in acquired immunodeficiency syndrome. A prospective study of 155 patients.

BACKGROUND AND AIMS: The optimum diagnostic investigation for patients with acquired immunodeficiency syndrome (AIDS) and diarrhoea is not known. Often no pathogen is detected and it is unclear whether this is because pathogens are absent in some patients or the investigations used fail to detect them. The hypothesis that AIDS related diarrhoea is usually due to an infection, which can be identified by a simple diagnostic strategy based on the results of intensive investigation of a cohort of such patients, was investigated. METHODS: 155 patients with AIDS and chronic diarrhoea underwent contemporaneous examination of stools, duodenal, jejunal, and rectal biopsy specimens and duodenal aspirate for bacterial, protozoal, and viral pathogens. A decision tree analysis was used to determine the best sequential diagnostic strategy for clinicians. RESULTS: 128 of 155 patients investigated (83%) had at least one potential pathogen. The presenting clinical features could not predict the presence or site of the pathogens. Stool analysis identified the most pathogens (93 of 199, 47%). Rectal biopsy was essential for the diagnosis of cytomegalovirus and adenovirus. Duodenal biopsy was as helpful as jejunal biopsy and detected some treatable pathogens missed by other methods. Electron microscopy, impression smears, and duodenal aspirate yielded little extra information. If gut biopsy was reserved for patients without a stool pathogen, some treatable pathogens would have been missed. CONCLUSION: Most patients with AIDS and chronic diarrhoea have at least one gut pathogen, which can be identified by stool analysis and light microscopic examination of duodenal and rectal biopsies. Some pathogens will be missed unless all these investigations are done on all such patients.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Evolutional analysis in determining pathogenic versus nonpathogenic mutations of ATPase 6 in human mitochondriopathy.

Because mitochondrial ATPase 6 plays an important role in ATP synthesis, mutations affecting ATPase 6 can undoubtedly cause human diseases. In contrast, the ATPase 6 gene is known to be a fast-evolving gene and has generated enough polymorphisms to allow identity investigation for forensic casework. To investigate these seemingly opposite views, we analyzed amino acid sequences of ATPase 6 in at least 1,266 humans, 102 mammals, and 213 vertebrates. The result showed that the amino acids of human ATPase 6 could be divided into the following four groups. Amino acid residue 192 (affected by alteration at nt 9101) and 79 other residues were variable, and therefore substitutions of these residues would not be pathogenic. Amino acid residue 156 (affected by alteration at nt 8993) and 93 other residues were conserved in Homo sapiens, but not in Mammalia. Therefore, they were potentially pathogenic if altered. Function studies would be necessary to confirm their role in pathogenesis. Amino acid residue 217 (affected by alteration at nt 9176) and 9 other residues were conserved across all species, including S. cerevisiae and E. coli. Mutations involving these residues would be pathogenic, some of which might even be life threatening. The remainder (42 residues) were conserved in Mammalia, but not in yeast and E. coli. They were probably pathogenic if mutated. The classification proposed in this study may, therefore, provide an algorithm for a diagnostic approach when a newly identified change of ATPase 6 is suspected for human mitochondriopathy.

Adenosine Triphosphatases↗
PubMed1998

Immunization with Porphyromonas gingivalis cysteine protease: effects on experimental gingivitis and ligature-induced periodontitis in Macaca fascicularis.

Targeting bacterial virulence factors such as proteases for immunization may hold the key to limiting or preventing loss of attachment and alveolar bone in periodontal disease. This study examined the clinical, microbiological, and immununological responses following active immunization with a purified Porphyromonas gingivalis cysteine protease (porphypain-2) in the nonhuman primate (Nhp) Macaca fascicularis. One group of Nhp was immunized with porphypain-2 antigen while control Nhp received placebo injections. All Nhp were subjected to experimental gingivitis followed by ligature-induced periodontitis in a split-mouth design. An enzyme-linked immunosorbent assay demonstrated that immunization elicited a significantly elevated and specific IgG antibody response to both whole cell P. gingivalis (36-fold) and to porphypain-2 (194-fold). Checkerboard hybridization DNA analysis of subgingival plaque from ligated sextants demonstrated that 25% more Gram-negative anaerobic species became significantly elevated from baseline and at earlier timepoints in the control group than in the immununized group. Immunization with this protease did not suppress the emergence of P. gingivalis. Clinical indices showed few changes related to immunization. Alveolar bone density changes demonstrated a highly significant loss in ligated sextants compared to non-ligated sextants within the control group (P < 0.001), and a smaller but significant difference within the immunized group (P = 0.043). Comparison of ligated sextants only demonstrated more bone loss in the control group versus the immunized group (-13.07+/-9.51 versus -9.41+/-6.18; computer-assisted densitometric image analysis units +/- SD); the difference approached, but did not reach, significance. The results suggest that porphypain-2 may contribute to the pathogenic potential of the subgingival plaque microbiota in the Nhp model of ligature-induced periodontitis, and that active immunization with porphypain-2 appeared capable of altering this pathogenic response.

Absorptiometry, Photon↗