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The effect of ascorbic acid deficiency on leukocyte phagocytosis and killing of actinomyces viscosus.

The ascorbic acid content of guinea pig leukocytes is reduced by a factor of 16:1 between normal and scorbutic guinea pigs. Ascorbic acid deficiencies do not appear to affect phagocytic activity but do change leukocyte morphology. A deficiency of this vitamin appears to significantly interfere with the in vitro bactericidal effectiveness of circulating leukocytes against ingested, cell-associated, and extracellular bacterial cells of the oral pathogen, Actinomyces viscosus. Leukocytes from scorbutic guinea pigs killed 13% of ingested and cell-associated Actinomyces viscosus compared to 83% killed by normal leukocytes by both acridine orange staining and viable count. Degranulation resulted in extracellular killing in normal but not scorbutic leukocytes. This decreased bactericidal activity can be reversed by adding supplements of the vitamin to the diet of scorbutic animals. Chemotactic responses were much lower in vivo and absent in vitro in scorbutic leukocytes. The acridine orange staining technique is an excellent indicator of leukocyte health. This study supports the important role for ascorbic acid in leukocyte function and also discusses its probable protective and bactericidal activities related to oral pathogens.

Actinomyces↗

A study of in vitro attachment of Streptococcus sanguis and Actinomyces viscosus to saliva-treated titanium.

This study examined the initial attachment of Streptococcus sanguis G9-B and Actinomyces viscosus T14V to saliva-treated powdered enamel and titanium surfaces. Using an in vitro adherence model, significantly lower numbers of Actinomyces viscosus T14V bound to the saliva-treated titanium surface when compared to that of the similarly treated enamel. The binding of Streptococcus sanguis G9-B to titanium or enamel did not vary significantly. A comparison of the percentage of cells bound to the titanium surface revealed that S sanguis cells attached in significantly higher numbers when compared to the A viscosus cells.

Actinomyces↗

Cytologic changes associated with vaginal pessary use. With special reference to the presence of Actinomyces.

The cytopathology of Papanicolaou smears from 23 postmenopausal women with vaginal pessaries is described. The following alterations, when seen in the smear of an elderly postmenopausal woman, were found to be strongly suggestive of pessary use: cytologic atypia in the form of severe inflammatory changes in squamous cells, atypical metaplasia, and reparative changes with a background pattern of acute inflammation and prominent superficial maturation of the squamous cells. A notable additional finding in 13 of the 23 patients was the presence of filamentous organisms resembling Actinomyces and morphologically similar to organisms recently described and specifically identified as Actinomyces in patients with intrauterine devices.

Actinomyces↗

Coaggregation between Actinomyces viscosus with Streptococcus pyogenes and Streptococcus agalactiae.

Interbacterial coaggregation between Actinomyces viscosus indigenous to the human mouth and Streptococcus pyogenes and Streptococcus agalactiae was studied. Fifteen of twenty-six strains of Streptococcus pyogenes and thirteen of thirty-one Streptococcus agalactiae showed a coaggregation with Actinomyces viscosus strain. The results show that the coaggregation mechanism required calcium and was dependent on pH. Some coaggregations were inhibited by 0.06 M. lactose and by 1 M. NaCl.

Actinomyces↗

[Pulmonary Actinomyces-viscosus infection].

The isolation of Actinomyces viscosus from the pleural fluid of a patient with pleuro-pneumonia and empyema is described. This is believed to be the first human Actinomyces viscosus infection in Switzerland.

Actinomyces↗

[New actinomycin from Actinomyces sp. No. 2].

A new actinomycin was isolated from a mixture of actinomycins formed by Actinomyces sp. No. 2, an organism producing auranthin, an actinomycetous antibiotic. The peptide chains of the new actinomycin contain such amino acids as threonine, valine, proline and sarcosine in a ratio of 2 : 4 : 2 : 2. N-Methyl-valine characteristic of all actinomycins is replaced in position 5 of both pentapeptide chains of the new actinomycin by valine. The new actinomycin is actinomycin D undermethylated in position 5 by valine. When the growing culture of Actinomyces olivobrunneus producing actinomycin D was exposed to sulfadimesine, an inhibitor of biological methylation, production of actinomycin D0 (sarcosine replaced by glycine in one of the pentapeptide chains) markedly increased, which indicated impairment of the glycine residue methylation. Still, no impairment of the valine residue methylation in position 5 of the pentapeptide chains was observed an no actinomycin with N-methyl-valine replaced by valine was formed.

Actinomyces↗

Mitogenic activity of Actinomyces viscosus. I. Effects on murine B and T lymphocytes, and partial characterization.

Actinomyces viscosus homogenate (AVIS) contins substance(s) which cause spleen cells from conventional and germfree mice to undergo increased DNA synthesis. This mitogenic effect is primarily on B cells since spleen cells from nude mice or T-depleted spleen cells from conventional mice respond as strongly as conventional (T + B) spleen cells. Mouse thymocytes do not respond mitogenically to AVIS. It is unlikely that the mitogenic acitivity is due to the presence of LPS, since A. viscosus is Gram-positive and is not known to have an LPS cell wall component. Also, AVIS is not inactivated by polymyxin B, as are some preparations of LPS, and C3H/HeJ mouse splenocytes respond strongly to AVIS but not to LPS. The activity is heat stable, is not lost upon dialysis, and is not affected by lysozyme. Mitogenic activity is partially lost when AVIS is digested with nonspecific bacterial protease or treated with metaperiodate. Sodium hydroxide treatment completely abolishes mitogenic activity. Actinomycotic lesions are characterized by a long-tern inflammatory response involving a dense plasma cell infiltrate. We suggest that B cell mitogens form Actinomyces may play a role in the elicitation of the plasma cell component of these lesions.

Actinomyces↗

[Effect of the nutrient medium composition on biotin biosynthesis by an Actinomyces species 313-152 culture].

The effect of the composition of the nutrient medium on the biosynthesis of biotin by the culture Actinomyces species 313-152 was investigated. This microorganism can synthesize biotin on simple and complex media. The biotin synthesis is stimulated by oleic acid and Tween-80 utilized by the culture as a carbon source. The exogenous biotin added at concentrations of 1 x 10(-8) M to 1 x 10(-6) M to the medium containing fodder yeast hydrolyzate and Tween-80 did not inhibit the synthesis by the culture Actinomyces species 313-152.

Actinomyces↗

Microbiological study of mycetoma patients from Bombay with special reference to actinomyces immunofluorescence.

17 of the 21 clinically diagnosed mycetoma and actinomycosis cases studied yielded positive cultures. Foot, leg, inguinal region, chest wall, jaw and scalp were the affected sites. 15 of the patients were from Bombay, 13 of them had infection due to Nocardia species and 2 had Actinomyces israelii infection. The other two patients from South India had Madurella mycetomi infection. N.brasiliensis was commonest isolate (8). Other isolates were N.asteroides (2), N.pelletieri (2), N.caviae (1) and A.israelii (2). A direct fluorescent antibody test to detect actinomyces was used in selected cases (4). Two of whom gave positive immunofluorescence with A.israelii FITC labeled globulin, in primary smears as well as in cultures.

Actinomyces↗

Biochemical and ribotypic comparison of Actinomyces pyogenes and A pyogenes-like organisms from liver abscesses, ruminal wall, and ruminal contents of cattle.

OBJECTIVE: To isolate Actinomyces pyogenes and A pyogenes-like (APL) organisms from the ruminal wall and ruminal contents of cattle and compare them with isolates from liver abscesses from the same animals, using ribosomal DNA restriction fragment length polymorphism analysis or ribotyping. PROCEDURE: Specimens of liver abscesses, ruminal walls, and ruminal contents were collected from 59 cattle at slaughter. All beta-hemolytic, pinpoint colonies that were gram positive, pleomorphic rod-shaped, and catalase negative, and that hydrolyzed casein and gelatin were presumptively identified as A pyogenes and were characterized biochemically, using an identification kit. The isolates that resembled A pyogenes but fermented mannitol or raffinose, or both, were called APL organisms. Isolates from the ruminal wall and ruminal contents were compared with liver abscess isolates from the same animal by use of ribotyping. RESULTS: Actinomyces pyogenes and APL organisms were isolated more frequently from the ruminal wall than from ruminal contents. Ruminal isolates of A pyogenes and APL had biochemical characteristics similar to those of the isolates from liver abscesses. Among 6 sets of isolates (4 A pyogenes and 2 APL), 2 isolates from liver abscesses had ribopatterns identical to the corresponding ruminal wall isolates. Also, the APL organisms isolated from the ruminal content matched with the corresponding liver abscess isolates for both sets of specimens tested. CONCLUSIONS: The ruminal wall may be the niche for A pyogenes and APL organisms in the rumen. The genetic similarity, on the basis of ribotyping among isolates from liver abscesses, the ruminal wall, and ruminal contents of the same animal suggests that A pyogenes and APL organisms that cause liver abscesses originate from the rumen.

Abscess↗

[Pulmonary actinomycosis: caused by Actinomyces odontolyticus?].

Primary pulmonary actinomycosis is a purulent bronchopulmonary disease mimicking tuberculosis. The histological lesions contain characteristic yellow granules. The organism most frequently responsible for the disease is Actinomyces israeli. We report the first case to our knowledge where Actinomyces odontolyticus seems to be involved.

Actinomycosis↗

Necrotizing pneumonia caused by mixed infection with Actinobacillus actinomycetemcomitans and Actinomyces israelii: case report and review.

Actinobacillus actinomycetemcomitans is an important cause of human pulmonary infections, either alone or with Actinomyces species. It may be critical to isolate Actinobacillus in patients with pulmonary infection for selection of an effective antimicrobial regimen. Clindamycin has superseded penicillin as the sole antimicrobial drug for anaerobic bacterial necrotizing pneumonia and abscess. In the case presented herein, therapy with clindamycin failed to halt worsening necrotizing pneumonia or to prevent hematogenous dissemination. After clindamycin-resistant A. actinomycetemcomitans in addition to Actinomyces israelii were isolated, the patient was treated with penicillin, ciprofloxacin, and cefazolin and was ultimately cured.

Actinobacillus Infections↗

Disseminated infection due to Actinomyces meyeri: case report and review.

Actinomyces meyeri is rarely isolated in cases of actinomycosis. We present a case of disseminated actinomycosis due to A. meyeri; the patient had an abscess of the lung, osteomyelitis of the tibia, and multiple skin abscesses. Cure was achieved with surgical debridement and administration of intravenous penicillin, followed by oral penicillin, for 1 year. A concomitant gram-negative bacillus, Actinobacillus actinomycetemcomitans, was also isolated. Review of the literature revealed only 26 well-documented cases of infection with A. meyeri. Male adults are mainly affected, and alcoholism is frequently the underlying condition in these patients. Associated bacteria were isolated in two-thirds of these cases. In contrast to other species of Actinomyces, A. meyeri often causes pulmonary infection and shows a tendency for hematogenous dissemination. Even though multiple organs are involved, the outcome for these patients is excellent when penicillin is administered for several months and surgical procedures are performed when necessary.

Abscess↗

Extensive Actinomyces naeslundii infection in a child.

A case of extensive Actinomyces naeslundii infection in a globally retarded patient is reported. To our knowledge, this uncommon Actinomyces species has not previously been described as a cause of widespread disease. Mental retardation and thoracic scoliosis were identified as features predisposing to infection.

Actinomycosis↗

Isolation of gram-positive rods that resemble but are clearly distinct from Actinomyces pyogenes from mixed wound infections.

Beginning in 1990, gram-positive rods resembling Actinomyces pyogenes were found with increasing frequency in mixed cultures from various infectious processes, most of them from patients with otitis, empyema, pilonidal cysts, perianal abscesses, and decubitus ulcers. Ribotyping and hybridization showed that these gram-positive rods could be divided into five groups not related to known Actinomyces species. Biochemical markers for reliable differentiation into these groups, however, could not be found. Therefore, naming new species is not warranted unless parameters are discovered that allow identification without DNA hybridization. These gram-positive rods have been isolated only in mixed cultures with anaerobes, Staphylococcus aureus, Streptococcus "milleri," enterococci, and gram-negative rods. Their exact role in these possibly synergistic infections needs further investigation.

Adult↗

Mixed fusobacterium and actinomyces pulmonary infection. Case report.

This is a report of a twelve-year-old black male who presents a history of left neck pain, left shoulder pain, weight loss and minimal fever. The admission diagnosis was a malignancy, supported by radiographic findings of consolidation of left lower and left upper lobes and periosteal new bone formation along the inferior aspects of the left second, third and fourth ribs. Open biopsy of the chest wall revealed a large abscess cavity. Subsequent cultures on anaerobic blood agar plates grew Actinomyces and Fusobacterium. The patient was treated with penicillin and improved clinically. This case emphasizes the need to culture tissue specimens for a wide array of organisms, including those not commonly seen today. A high index of suspicion is required for the diagnosis of anaerobic infections. Mixed anaerobic infections, including actinomyces, although uncommon in children, should be considered in the etiology of an intrathoracic mass.

Actinomycosis↗

Fusobacterium necrophorum and Actinomyces pyogenes associated facial and mandibular abscesses in blue duiker.

Anaerobic and aerobic cultures of facial and mandibular abscesses were made from 12 blue duiker (Cephalophus monticola fusicolor) housed at the Deer and Duiker Research Facility of the Pennsylvania State University (USA). Increases in concentrations of total protein and serum globulin occurred in all cases. Actinomyces pyogenes was isolated from nine animals. Fusobacterium necrophorum was present in eight and Bacteroides sp. was found in seven animals; other genera of isolated bacteria included: Streptococcus (from two animals), Lactobacillus (one), Staphylococcus (one) and Actinomyces (two). Eight (67%) of affected animals were less than or equal to 2 yr of age. Facial soft tissues and mandibles were the tissues most often affected. Tissues within the oral cavity were not affected at the time of presentation. A common finding, not reported in other host species with necrobacillosis, was the presence of nondestructive mandibular proliferation.

Abscess↗

Actinomyces and nocardia infections in immunocompromised and nonimmunocompromised patients.

A retrospective survey of nocardia and actinomyces infections in five local hospitals was conducted over a 3-year period in El Paso, Texas, a border city, in the southwestern United States. The medical records of 42 patients with suspected nocardiosis or actinomycosis were reviewed. One patient was diagnosed with actinomyces and 12 patients with nocardia. Microbiological data included morphologic characteristics, biochemical profile, and susceptibility testing. Predisposing factors included leukemia, renal insufficiency, renal transplant, and lymphoma. No predisposing factors were found in 67% (n = 8) of patients (including the patient with actinomycosis). Twenty-three percent (n = 3) of patients had disseminated disease without evidence of underlying disease or immunosuppression. The mortality and morbidity of these infections appeared to be low.

Actinomycosis↗