Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0043352 (xerostomia)
 4,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To assess the role of reduced salivary flow and intraoral pH on gram-negative bacterial colonization of the oropharynx, we studied in vitro Klebsiella adherence to normal human buccal epithelial cells at various pH values and to buccal cells from patients with pathological xerostomia (decreased saliva flow). Reduced pH significantly increased adherence of Klebsiella pneumoniae 84 to normal buccal epithelial cells (P less than 0.001). In contrast, two clinical isolates of K. oxytoca showed no significant pH-dependent change in adherence. A corollary of this was that patients with pathological xerostomia had significantly increased adherence of K. pneumoniae 84 to their buccal epithelial cells as compared with normal controls (P less than 0.01). These results suggest that reduced salivary flow and the concomitant reduction of intraoral pH may predispose patients to bacterial colonization with K. pneumoniae.
 ...
PMID:Effect of decreased salivation and pH on the adherence of Klebsiella species to human buccal epithelial cells. 675 12

This study aimed at investigating the oral colonization of aerobic and facultatively anaerobic gram-negative rods and cocci in head- and neck-irradiated, dentate, xerostomic individuals. Subjects were recruited from a nasopharyngeal carcinoma clinic and were segregated into group A: <60 years (n=25, 48+/-6 years, 5+/-5 years post-irradiation) and group B: >or=60 years (n=8, 67+/-4 years, 2+/-2 years post-irradiation) and were compared with age- and sex-matched normal individuals, group C: <60 years (n=20, 44+/-12 years) and group D: >or=60 years (n=10, 70+/-3 years). Selective culture of the oral rinse samples was carried out to isolate, quantify and speciate (using API 20E kit) aerobic and facultatively anaerobic gram-negative rods and cocci recovery. All test subjects were put under comprehensive oral and preventive care for 3 months, and 12 group A and 5 group B subjects were recalled for reassessment of aerobic and facultatively anaerobic gram-negative rods and cocci colonization. All identical isolates, pre- and post-hygienic care, were phenotypically (Vitek, Hazelwood, MA and antibiogram profile) and genotypically (pulsed-field gel electrophoresis) evaluated. The aerobic and facultatively anaerobic gram-negative rods and cocci isolated from the first round oral rinse samples included: Acinetobacter, Neisseria, Chryseomonas, Flavimonas, Pseudomonas, Citrobacter, Enterobacter, Escherichia, Klebsiella, Flavobacterium and Weeksella species. The aerobic and facultatively anaerobic gram-negative rods and cocci isolation rate was high for irradiated individuals, and they were 64/25% and 100/80% for groups A/C and B/D, respectively. Recovery of aerobic and facultatively anaerobic gram-negative rods and cocci and Klebsiella pneumoniae subsp. pneumoniae in oral rinse samples were found to be significantly more prevalent in the irradiated subjects (groups A and B). Enterobacteriaceae were more frequently isolated from oral rinse samples of aged irradiated subjects (group B vs D, P<0.05), where the quantity of Citrobacter freundii (colony-forming units/ml oral rinse) was also significantly elevated. The isolation rate of aerobic and facultatively anaerobic gram-negative rods and cocci after hygienic care remained unchanged; 3 of 12 and 3 of 5 of the recalled subjects from groups A and B, respectively, harbored same aerobic and facultatively anaerobic gram-negative rods and cocci species. However, only two pairs of K. pneumoniae subsp. pneumoniae, sequentially isolated from same patients in group B, were found to be identical by pulsed-field gel electrophoresis. This may be due to reinfection of the microbes from the same source or permanent colonization. In conclusion, irradiation-induced xerostomia seems to favor frequent, repeated, transient intraoral colonization of aerobic and facultatively anaerobic gram-negative rods and cocci.
 ...
PMID:Oral colonization of aerobic and facultatively anaerobic gram-negative rods and cocci in irradiated, dentate, xerostomic individuals. 1116 32