Nasser Haghighat

Evaluation of the levels of oral Candida in patients with Sjögren's syndrome

OBJECTIVE The purpose of this study was to investigate the levels of oral Candida in patients with Sjögrens syndrome METHODS The Candida count and salivary flow rate of patients with Sjögrens syndrome were compared with those of healthy control subjects. Candida cultures were obtained from oral rinses. The numbers of colony-forming units were determined through use of the Spiral System. RESULTS The mean Candida count of patients with Sjögrens syndrome was 1672 +/- 1455 colony-forming units per mL; the count of healthy control subjects was 0.00 colony-forming units per mL. The mean salivary flow rate of patients with Sjögrens syndrome was significantly lower than that of healthy control subjects (0.16 +/- 0.13 mL/min/gland vs 0.55 +/- 0.24 mL/min/gland, respectively; p = 0.0001). However, Spearman rank correlation analyses did not reveal a significant correlation between salivary flow rate and Candida count (in colony-forming units per mL) among patients with Sjögrens syndrome. CONCLUSIONS Alteration in the oral microbial flora in patients with Sjögrens syndrome may be enhanced by the reduction in salivary output.

Salivary electrophoresis in the diagnosis of Sjögren's syndrome

OBJECTIVE The purpose of this study was to investigate the potential use of salivary electrophoresis for the diagnosis of Sjögrens syndrome. METHODS Salivary protein profiles of 43 patients and 39 healthy control subjects were compared on three different gel electrophoresis systems: sodium dodecylsulfate-polyacrylamide gel electrophoresis, anionic polyacrylamide gel electrophoresis, and immobilized pH gradient gel electrophoresis (isoelectric point, 3.5-5.0). RESULTS Most of the patients with Sjögrens syndrome exhibited an electrophoretic profile that was different from that of the healthy control subjects. Among the three gel electrophoresis systems examined, the immobilized pH gradient system appeared to be the most reliable for Sjögrens syndrome. Tests of accuracy revealed that the immobilized pH gradient system exhibits high specificity (97%), sensitivity (95%), positive predictive value (97%), and negative predictive value (95%) in the diagnosis of Sjögrens syndrome. CONCLUSIONS Our results suggest that salivary electrophoresis is a potentially useful test for the diagnosis of Sjögrens syndrome.

A pilot study on the effect of radiation on calmodulin in rat submandibular salivary glands

Xerostomia and loss of salivary gland secretion is one of the most common complications of the radiation treatment of head-and-neck malignancies. The secretory mechanism in the salivary glands can be modulated by the concentration of intracellular Ca2+. Calmodulin is a calcium-binding protein that is widely distributed in nature and is involved in regulating intracellular calcium. In this study the effect of radiation on the concentration of calmodulin in rat salivary glands was investigated. Fourteen rats were divided into three groups: R1 (n = 4) and R2 (n = 5) received a single dose of 15 Gy and group C (n = 5) received no radiation. R1 and R2 animals were killed at weeks 2 and 10 post-irradiation, respectively. The submandibular glands were removed, homogenized and their total calmodulin was determined. The mean calmodulin concentrations were 6.4+/-1.1 microg/gland for controls, 14.1+/-3.7 microg/gland for R1 and 68.2+/-14.4 microg/gland for R2. Kruskal-Wallis ANOVA revealed a significant increase in the concentration of calmodulin following irradiation (p = 0.003). The relationship between this increase and the loss of salivary gland function is not yet clear.