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At least 19 recordsLinked to original sources
PubMed2026

Lesion-specific oral microbiome signatures and predicted carcinogenic pathways in oral squamous cell carcinoma: a paired-site study in Pakistan.

BACKGROUND: Oral squamous cell carcinoma accounts for over 90% of oral neoplasms. Despite therapeutic advances, the lack of reliable, non-invasive biomarkers and delayed diagnosis continues to impede effective clinical management. By combining paired lesion and non-lesion sampling with predictive metagenomics analysis, our study addresses this gap and advances the current understanding of microbiome&#x2012;tumor interactions. METHODS: We analyzed 92 buccal swab samples from 39 OSCC patients and 14 healthy controls using 16S rRNA gene (V3-V4) sequencing. Taxonomic profiling was conducted using QIIME2 and SILVA/eHOMD databases, functional pathways were predicted using PICRUSt2, and hub taxa were identified through co-abundance network analysis. RESULTS: Microbial community structure differed significantly across lesion, non-lesion, and healthy sites (PERMANOVA, p&#x2009;=&#x2009;0.001). Lesions were enriched with Selenomonas infelix and Treponema vincentii, while healthy controls harbored Streptococcus oralis and Gemella haemolysans. Co-abundance network analysis revealed lesion-specific hub species, notably T. vincentii, strongly correlated with predicted activation of pyrimidine biosynthesis pathways (r&#x2009;=&#x2009;0.69, q&#x2009;<&#x2009;1E-6), suggesting predicted metabolic alterations in the tumor microenvironment. Non-lesion sites were also characterized by two hub species, Prevotella melaninogenica and Segatella oulorum. CONCLUSION: Our findings define a lesion-specific microbial signature of OSCC characterized by the depletion of health-associated taxa, enrichment of pro-inflammatory pathobionts, and predicted associations with metabolic pathways implicated in carcinogenesis. These alterations reflect a predicted functionally altered tumor microenvironment.

16S rRNA gene↗
PubMed1979

Anaerobic isolates in chronic recurrent suppurative otitis media. Treatment with carbenicillin alone and in combination with gentamicin.

Tympanocentesis was performed in 32 pediatric patients with chronic recurrent suppurative otitis media. The aspirate was cultured aerobically and anaerobically. Aerobes were isolated from ten patients (31.2%); anaerobes from one patient; and both aerobes and anaerobes from 21 patients (65.6%). There were 46 aerobic isolates. The aerobes commonly recovered were Pseudomonas aeruginosa (24 isolates) Proteus sp. (5) and Staphylococcus aureus (3). There were 32 anaerobes isolated including anaerobic gram-positive cocci (19 isolates) and Bacteroides sp., the latter of which included Bacteroides fragilis group and Bacteroides melaninogenicus (9). The patients were treated by parenteral carbenicillin 300 to 400 mg per kg per day given in four dosages administered for a period of 12 to 21 days (average 17 days). An aminoglycoside (gentamicin) was added in 15 patients. The clinical response was good in 17 patients and poor in 15. There were no side effects or adverse reactions noted during therapy. The above findings demonstrate the polymicrobial etiology of chronic recurrent suppurative otitis media and suggest that treatment directed against the aerobic and anaerobic isolates is efficacious in more than half of the cases.

Adolescent↗
PubMed1978

Pleuropulmonary lung infection by anaerobic bacteria.

Two patients with severe pleuropulmonary infection caused by non-sporing anaerobic bacteria are described. One had an empyema with foul-smelling pus and developed bacteraemia, and the other developed a lung abscess. Both were successfully treated with antibiotics and drainage, chest surgery being avoided. The successful diagnosis and treatment of these patients involved close liaison between clinical and laboratory staff.

Adult↗
PubMed1976

Bacteroides: an unusual cause of breast abscess.

Three cases of breast abscess from which the non-sporing anaerobe Bacteroides was isolated are described. This organism has apparently not previously been reported as a cause of abscess in a breast without underlying malignancy.

Abscess↗
PubMed1977

Inhibition of phagocytosis in vitro by obligate anaerobes.

A variety of species of obligate anaerobes have been shown to interfere with the phagocytosis and killing of Proteus mirabilis and other aerobic bacteria in vitro. Although all the obligate anaerobes examined showed this activity, the effect was greatest with strains of Bacteroides melaninogenicus and B. fragilis. In contrast, none of the 36 aerobes tested acted in this way. These observations suggest that the presence of obligate anaerobes may be fundamental to the pathogenesis of some types of infections.

Bacteroides↗
PubMed1978

Abscesses of the frontal lobe of the brain secondary to covert dental sepsis.

The bacterial species found in pus aspirated from brain abscesses in two patients were typical of those found in dental sepsis. Subsequently apical-root abscesses were demonstrated in the upper jaws of both patients. This evidence strongly suggests that these cerebral abscesses were secondary to dental sepsis which could have spread from the teeth to the frontal lobes by several possible antaomical pathways.

Actinobacillus Infections↗
PubMed1979

The porphyrin pigmentation of subspecies of Bacteroides melaninogenicus.

Various subspecies of Bacteroides melaninogenicus differ in their pigmentation. Subsp. asaccharolyticus produces protohaem almost exclusively, subsp. intermedicus both protohaem and a smaller proportion of protoporphyrin, and subsp. melaninogenicus mainly protoporphyrin with a trace of protohaem. As a consequence young colonies can be differentiated by their red fluorescence in u.v. light (365nm): subsp. asaccharolyticus does not fluoresce, subsp. intermedicus shows a limited fluorescence, and subsp. melaninogenicus shows a bright fluorescence. The pigments were isolated as the dimethyl esters of protohaemin and of protoporphyrin and identified by electronic spectroscopy, mass spectrometry and comparisons by t.l.c. Incorporation of delta-aminolaevulinate into these pigments was not detected, nor was porphobilinogen formation observed. Subsp. melaninogenicus grown in the presence of [14C]protohaemin formed [14C]protoporphyrin. This appears to represent a novel biological demetallation.

Bacteroides↗
PubMed1979

Sphingolipid biosynthesis and vitamin K metabolism in Bacteroides melaninogenicus.

B. melaninogenicus provides a unique system for the study of the biosynthesis of an important group of lipids, the phosphosphingolipids. Sphingolipid biosynthesis can be repressed and induced by depletion and restoration of vitamin K. At least one enzyme involved in sphingolipid biosynthesis from the microorganism can be solubilized and so purified by conventional methods. Pathways involved in biosynthesis may differ from hitherto postulated pathways, for example, the incorporation of NH4+ into ethanolamine residue of ceramide phosphorylethanolamine. Moreover, the derivation of mutants defective in steps in sphingolipid biosynthesis would be of great value in these studies.

Animals↗
PubMedDate not supplied

Immunochemical characterization of surface antigens of Bacteroides melaninogenicus.

Major surface antigens of Bactmbrane complex by gentle methods, purified, and characterized immunochemically. A lipopolysaccharide (LPS) was found to be chemically distinct from the LPS of facultative gram-negative bacteria in that it lacked two core sugars, 2-keto-3-deoxyoctonate and heptose, as well as beta-hydroxymyristic acid, the predominant fatty acid in the lipid A moiety. The LPS was further atypical in that it had a very low level of biologic activity. A capsular polysaccharide was demonstrated morphologically by electron microscopy with ruthenium red staining and a ferritin-labeled antibody technique. This antigen was shown to be subspecies-specific by indirect immunofluorescence. Antibody to the capsular polysaccharide was measured by an enzyme-linked immunospecific assay. The presence of a relatively impotent LPS and a surface capsular antigen may partly explain the rarity of bacteremia and septic shock due to B. melaninogenicus subspecies asaccharolyticus and the common association of this organism with abscess formation.

Animals↗