Endoplasmic reticulum stress affects mouse salivary protein secretion induced by chronic administration of an α1-adrenergic agonist.

Stress stimulates both the sympathetic-adrenomedullary and hypothalamus-pituitary-adrenal axes. Activation of these axes results in the release of catecholamines, which in turn affects salivary secretion. Thus, repetitive stimulation of the α1-adrenergic receptor could be useful for studying the effects of chronic stress on the salivary gland. Salivary protein concentration and kallikrein activity were significantly lower in mice following chronic phenylephrine (PHE) administration. Chronic PHE administration led to significantly increased expression of the 78-kDa glucose-regulated protein, activating transcription factor 4, and activating transcription factor 6. Histological analyses revealed a decrease in the size of the serous cell and apical cytoplasm. These results suggest that repetitive pharmacological stimulation of the sympathetic nervous system elicits ER stress and translational suppression. In addition, PHE-treated mice exhibited a decrease in intracellular Ca2+ influx elicited by carbachol, a muscarine receptor agonist in the submandibular gland. The present findings suggest that chronic psychological, social, and physical stress could adversely affect Ca2+ regulation.

Microbicidal effect of 405-nm blue LED light on Candida albicans and Streptococcus mutans dual-species biofilms on denture base resin.

This study investigated: (1) the microbicidal effect of 405-nm blue LED light irradiation on biofilm formed by Candida albicans hyphae and Streptococcus mutans under dual-species condition on denture base resin, (2) the generation of intracellular reactive oxygen species (ROS) induced by irradiation, and (3) the existence of intracellular porphyrins, which act as a photosensitizer. Denture base resin specimens were prepared and C. albicans and S. mutans dual-species biofilms were allowed to form on the specimens. The biofilms were irradiated with 405-nm blue LED light and analyzed using the colony-forming unit assay, fluorescence microscopy, and scanning electron microscopy (SEM). Single-species biofilms of C. albicans and S. mutans formed on the specimens were irradiated with 405-nm blue LED light. After the irradiation, the intracellular ROS levels in C. albicans and S. mutans cells were measured. In addition, the level of intracellular porphyrins in C. albicans and S. mutans were measured. Irradiation for more than 30 min significantly inhibited the colony formation ability of C. albicans and S. mutans. Fluorescence microscopy revealed that almost all C. albicans and S. mutans cells were killed by irradiation. SEM images showed various cell damage patterns. Irradiation led to the generation of intracellular ROS and porphyrins were present in both C. albicans and S. mutans cells. In conclusion, irradiation with 405-nm blue light-emitting diode light for 40 min effectively disinfect C. albicans hyphae and S. mutans dual-species biofilms and possibly react with intracellular porphyrins resulting in generation of ROS in each microorganism.

Inhibitory effect of 405-nm blue LED light on the growth of Candida albicans and Streptococcus mutans dual-species biofilms on denture base resin.

We investigated whether irradiation with 405-nm blue LED light could inhibit the growth of not only single- but dual-species biofilms formed by Candida albicans and Streptococcus mutans on denture base resin and cause the alteration in gene expression related to adhesion and biofilm formation. C. albicans and S. mutans single-/dual-species biofilms were formed on the denture base specimens. The biofilms were irradiated with 405-nm blue LED light (power density output: 280 mW/cm2) for 0 (control) and 40 min. Dual-species biofilms were analyzed using CFU assay and fluorescence microscopy, and single-/dual-species biofilms were analyzed using alamarBlue assays and gene expression analysis. To assess the inhibitory effect of irradiation on dual-species biofilms, specimens after irradiation were aerobically incubated for 12 h. After incubation, the inhibition of growth was assessed using CFU assays and fluorescence microscopy. Data were analyzed using the Mann-Whitney U or Student's t test (p < 0.05). Irradiation produced a significant inhibitory effect on biofilms. Fluorescence microscopy revealed that almost all C. albicans and S. mutans cells were killed by irradiation, and there was no notable difference in biofilm thickness immediately after irradiation and after irradiation and incubation for 12 h. alamarBlue assays indicated the growth of the biofilms was inhibited for 12-13 h. The expression of genes associated with adhesion and biofilm formation-als1 in C. albicans and ftf, gtfC, and gtfB in S. mutans-significantly reduced by irradiation. Irradiation with 405-nm blue LED light effectively inhibited the growth of C. albicans and S. mutans dual-species biofilms for 12 h.

Efficient diagnosis of Sjögren's syndrome to reduce the burden on patients.

OBJECTIVE: The purpose of this study was to investigate the procedures for efficiently diagnosing Sjögren's syndrome to reduce patient burden. METHODS: This study analyzed data from 254 Japanese patients diagnosed with Sjögren's syndrome out of 4967 who visited our clinic complaining of xerostomia. RESULTS: Of the 254 Sjögren's syndrome patients, 140 fulfilled the criteria proposed by the Committee on Sjögren's Syndrome of the Ministry of Health and Welfare of Japan, 228 fulfilled the criteria proposed by the American-European Consensus Group, and 69 fulfilled the criteria proposed by the American College of Rheumatology. Numbers of definitive cases varied with each set of criteria. Logistic regression analysis was used to analyze useful examination items for definitive diagnosis of Sjögren's syndrome, demonstrating that anti-Ro/SSA (odds ratio (OR), 7.165), lip biopsy (OR, 4.273), sialography (OR, 2.402), and ANA (OR, 0.678) correlated significantly with definitive diagnosis of Sjögren's syndrome. CONCLUSIONS: These results suggest that the following diagnostic procedure for Sjögren's syndrome would reduce burden on patients. When clinicians choose examination items for diagnosing Sjögren's syndrome, they should first select which criteria to use. Then, to minimize the number of examination items, examinations should be performed in order of anti-SSA antibody, lip biopsy, and parotid gland sialography.

Efficacy of Fungiflora Y staining for the diagnosis of oral erythematous candidiasis.

OBJECTIVE: The purpose of this study was to investigate the efficacy of Fungiflora Y staining (fluorescent stain) for the diagnosis of erythematous candidiasis. SUBJECTS AND METHODS: This study enrolled 48 patients who were diagnosed with erythematous candidiasis and who underwent fungal culture and microscopic examination of a smear specimen stained with CytoQuick (modification of the Giemsa stain) and Fungiflora Y. Fungiflora Y staining was observed using a portable fluorescent microscope (CyScope(®)). The sensitivity, specificity and positive and negative predictive values were calculated using fungal culture as the gold standard test. Accuracy was calculated, and the difference between the CytoQuick and Fungiflora Y groups was examined using contingency tables and the chi-square test. RESULTS: The sensitivity and specificity of the CytoQuick stain was 0.51 and 0.91, respectively; the positive predictive value was 0.95, and the negative predictive value was 0.36. The sensitivity and specificity of the Fungiflora Y stain was 0.84 and 1.0, respectively; the positive predictive value was 1.00, and the negative predictive value was 0.65. The accuracy of Fungiflora Y (0.88) was superior to that of CytoQuick (0.60) (p = 0.0052). CONCLUSIONS: Microscopic examinations of smear specimens using a combination of Fungiflora Y staining and the CyScope(®) portable fluorescent microscope was found to be useful for the diagnosis of oral erythematous candidiasis.

Inhibition of pilocarpine-induced saliva secretion by adrenergic agonists in ICR mice.

The aim of the present study was to clarify the effects of the adrenoceptor agonist isoproterenol (IPR) on saliva secretion stimulated by the muscarinic receptor agonist pilocarpine (PILO) in mice. Mice were injected with either 0.5 mg/kg, i.p. PILO alone or simultaneously with 2 mg/kg, i.p., IPR to evaluate the inhibitory effects of adrenoceptor agonists on saliva secretion. The mechanisms underlying changes in saliva flow rate were evaluated by histological examination of aquaporin 5 (AQP5) and saliva flow rate using the adenylate cyclase (AC) inhibitor SQ22536 (0.25 mg per mouse, s.c.), which was administered 30 min prior to PILO and/or IPR. Saliva volume decreased significantly in the mice treated simultaneously with PILO + IPR compared with that in mice treated with PILO alone. Changes in the intracellular localization of AQP5 were seen in PILO + IPR-treated mice, and those changes were reversed by SQ22536 pretreatment. In addition, the decreased salivary flow rate in the PILO + IPR-treated mice was partially restored by SQ22536 pretreatment. There were no significant changes in intracellular calcium or ATP levels among the groups. The results of the present study suggest the existence of an inhibitory effect of the sympathetic nervous system on parasympathetic-stimulated salivary secretion from the salivary gland.

Grapefruit seed extract effectively inhibits the Candida albicans biofilms development on polymethyl methacrylate denture-base resin.

This study aimed to investigate the cleansing effects of grapefruit seed extract (GSE) on biofilms of Candida albicans (C. albicans) formed on denture-base resin and the influence of GSE on the mechanical and surface characteristics of the resin. GSE solution diluted with distilled water to 0.1% (0.1% GSE) and 1% (1% GSE) and solutions with Polident® denture cleansing tablet dissolved in distilled water (Polident) or in 0.1% GSE solution (0.1% G+P) were prepared as cleansing solutions. Discs of acrylic resin were prepared, and the biofilm of C. albicans was formed on the discs. The discs with the biofilm were treated with each solution for 5 min at 25°C. After the treatment, the biofilm on the discs was analyzed using a colony forming unit (CFU) assay, fluorescence microscopy, and scanning electron microscopy (SEM). In order to assess the persistent cleansing effect, the discs treated with each solution for 5 min were aerobically incubated in Yeast Nitrogen Base medium for another 24 h. After incubation, the persistent effect was assessed by CFU assay. Some specimens of acrylic resin were immersed in each solution for 7 days, and changes in surface roughness (Ra), Vickers hardness (VH), flexural strength (FS), and flexural modulus (FM) were evaluated. As a result, the treatment with 1% GSE for 5 min almost completely eliminated the biofilm formed on the resin; whereas, the treatment with 0.1% GSE, Polident, and 0.1% G+P for 5 min showed a statistically significant inhibitory effect on biofilms. In addition, 0.1% GSE and 0.1% G+P exerted a persistent inhibitory effect on biofilms. Fluorescence microscopy indicated that Polident mainly induced the death of yeast, while the cleansing solutions containing at least 0.1% GSE induced the death of hyphae as well as yeast. SEM also revealed that Polident caused wrinkles, shrinkage, and some deep craters predominantly on the cell surfaces of yeast, while the solutions containing at least 0.1% GSE induced wrinkles, shrinkage, and some damage on cell surfaces of not only yeasts but also hyphae. No significant changes in Ra, VH, FS, or FM were observed after immersion in any of the solutions. Taken together, GSE solution is capable of cleansing C. albicans biofilms on denture-base resin and has a persistent inhibitory effect on biofilm development, without any deteriorations of resin surface.

[Duration of action of silodosin (KMD-3213) against phenylephrine-induced increase in intraurethral pressure in rats].

The duration of action of Silodosin (KMD-3213) against the phenylephrine-induced increase in intraurethral pressure in urethane-anesthetized rats was compared with that of tamsulosin hydrochloride. Silodosin, tamsulosin, or vehicle was orally administered to fasted male rats. Then, under urethane anesthesia, a cannula was inserted into the prostatic urethra. Phenylephrine, at a dose of 30 microg/kg, was infused (infusion rate: 36 ml/h; infusion time: 100 s/kg) via the femoral vein at 12 h, 18 h, or 24 h after administration of the study drug, and the intraurethral pressure in the prostate region was measured. Although the plasma silodosin concentration would have resolved within a few hours, silodosin significantly inhibited the phenylephrine-induced increase in intraurethral pressure (versus the vehicle-treated group) at 12 h, 18 h, and 24 h after its oral administration (at doses of 100 microg/kg and above, 1000 microg/kg and above, and 3000 microg/kg, respectively). On the other hand, tamsulosin hydrochloride showed no inhibitory action at 24 h after its oral administration at doses up to 3000 microg/kg. Thus, silodosin inhibits the phenylephrine-induced increase in intraurethral pressure for a longer time than tamsulosin hydrochloride.

Oxcarbazepine antinociception in animals with inflammatory pain or painful diabetic neuropathy.

1. Diabetic neuropathy is one of the most frequent complications of diabetes mellitus. However, the mechanisms underlying these disorders are not yet well defined and it has been reported that currently available analgesics have hardly any ameliorating effect on painful diabetic neuropathy. 2. The purpose of the present study was to evaluate the antinociceptive effect of oxcarbazepine (OCBZ), a keto derivative of carbamazepine (CBZ), in animal models generally used in pain research and in rats and mice with streptozotocin (STZ)-induced diabetes. In addition, we compared the effect of OCBZ with those of CBZ, mexiletine and morphine. 3. Diabetes was induced by injection of STZ at a dose of 300 mg/kg (i.p.) in mice and 50 mg/kg (i.v.) in rats. Experiments were conducted 2 weeks after STZ injection and those animals with a serum glucose level above 400 mg/dL were used for data analysis. Antinociceptive effects of the drugs were evaluated by the paw withdrawal test (normal, STZ-induced diabetic and carrageenin-injected rats), tail-flick test (normal and STZ-induced diabetic mice) and nociceptive behaviour (formalin-injected mice). 4. In the present study, diabetic mice showed thermal hyperalgesia and diabetic rats exhibited mechanical hyperalgesia. From these results, the STZ-induced diabetic animals used in the present study were found to be suitable for research on painful diabetic neuropathy. In STZ-induced diabetic animals, the antinociceptive effects of OCBZ, CBZ and mexiletine were facilitated, whereas the effect of morphine was attenuated, compared with effects in normal animals. 5. Oxcarbazepine inhibited the formalin-induced biphasic pain responses and increased the nociceptive threshold in the case of carrageenin-induced hyperalgesia. In view of these results, inhibition of substance P-mediated pain transmission may be involved in the antinociceptive action of OCBZ. 6. These results indicate that OCBZ has an analgesic action and is a possible therapeutic agent for the treatment of neuropathic pain, such as occurs in painful diabetic neuropathy.

Effect of ozagrel, a selective thromboxane A2-synthetase inhibitor, on cerebral infarction in rats. Comparative study with norphenazone, a free-radical scavenger.

The effects of ozagrel (CAS 82571-53-7), a thromboxane A2-synthetase inhibitor, and norphenazone (CAS 89-25-8), a free-radical scavenger, on cerebral infarction were assessed using the suture-induced middle cerebral artery occlusion (MCAO) model and a microthrombosis model. In the former model, the middle cerebral artery was occluded for 2 h, and the infarction area and volume were evaluated 24 h after the start of reperfusion. In the latter model, microthrombosis were induced by two injections of sodium laurate (interval, 2 days) into the internal carotid artery, and the neurologic deficits were evaluated on the day afer the 2nd injection. Ozagrel at 3 mg/kg decreased both the area and volume of the cortical infarction after ischemia-reperfusion of the middle cerebral artery. Ozagrel also had suppressive effects on the neurologic deficits in the microthrombosis model. Norphenazone at 1 and 3 mg/kg had no clear effects in either model. Since the suture-induced MCAO model and the microthrombosis model are models for occlusion-reperfusion of the major cerebral arteries and lacunar infarction, respectively, these results suggest a highly beneficial effect of ozagrel in the clinical therapy for stroke.