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AIMS: A number of previous studies have shown that plant extracts can inhibit formation of dental plaque. The ability of extracts of Rosmarinus officianalis L., Salvia officianalis L., unfermented cocoa, red grape seed and green tea to inhibit plaque bacteria, glucosyltransferase activity, glucan and plaque formation in an in vitro model using bovine teeth was examined. METHODS AND RESULTS: The antimicrobial activity of the plant extracts against oral bacteria was determined using a standard susceptibility agar dilution technique. Inhibition of growth and acid production from glucose and sucrose by Streptococcus mutans in liquid culture was investigated. Prevention of plaque formation on bovine teeth initiated by Strep. mutans was studied using an artificial mouth. The plant extracts inhibited the growth of oral bacteria and prevented acid production by Strep. mutans. Extracts inhibited glucosyltransferase activity and glucan production and inhibited adhesion to glass. Extracts of R. officianalis L. and S. officianalis L. at 0·25 mg ml(-1) reduced plaque growth by >80%. Green tea extract completely inhibited plaque formation but resulted in a greenish discolouration of the teeth which could not be removed by scrubbing. CONCLUSIONS: The plant extracts, particularly those from R. officianalis L. and S. officianalis L., inhibited glucosyltranferase activity, glucan production and plaque formation in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that the extracts of R. officianalis L. and S. officianalis L. may be useful as antiplaque agents in foods and dental preparations. Bovine teeth can be used as an alternative to hydroxyapatite for studies of plaque formation, but they need to be carefully sterilized before use.

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The minimum inhibitory concentrations (MIC) of commercially available and 70% aqueous propanone (P70) extracts from plants chosen for polyphenol content on Streptococcus mutans and other bacteria were determined using a standard susceptibility agar dilution technique to investigate their potential use as anticariogenic agents. The effects on adhesion of S. mutans to glass were also studied. The lowest MICs were for the P70 extracts of red grape skin (0.5 mg ml(-1)) and green tea and sloe berry skin (2 mg ml(-1)). The commercial extracts generally had a lower activity with a minimum MIC of 2 mg ml(-1) for tea extracts, grape seed extracts and Pynogenol (extract of maritime pine). All other extracts had MICs of > or = 4 mg ml(-1). Unfermented cocoa had greater antimicrobial activity than fermented cocoa and the activity of the fractionated extract increased with the extent of epicatechin polymerization. Epicatechin polymer had an MIC of 1 mg ml(-1) and an MBC of 64 mg ml(-1). Selected extracts were tested against other oral bacteria and showed activity against gram-positive organisms. P70 extracts of unfermented cocoa, epicatechin polymer fraction, green tea and red grape seed were bacteriostatic and prevented acid production when added at the MIC to cultures of S. mutans grown in a chemically defined medium supplemented with either glucose or sucrose. There was a reduction in viability which was greater when added to washed cells, but there were some viable cells after 24 h. The extracts also reduced adherence of S. mutans to glass.

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The purpose of this study was to examine the use of Chromocult agar medium for isolation and enumeration of Enterobacteriaceae from human faecal samples, to compare it to MacConkey agar and to evaluate its usefulness as a possible alternative selective medium in human faecal studies. The medium was shown to be effective in identifying Escherichia coli and coliforms in faeces without the need for extensive accompanying biochemical tests for confirmation of identity. A positive correlation (r=0.86) was found between the recovery of Enterobacteriaceae on the two media, and no significant difference (P>0.05) between overall mean bacterial counts for the whole study group or at different intervals of faecal collection were observed. Chromocult agar is an effective replacement for MacConkey agar in human faecal studies and has the advantage of differentiating E. coli from other coliforms.

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The purinergic regulation of ciliary activity was studied using small, continuously superfused explants of human nasal epithelium. The P2Y(2) purinoceptor (P2Y(2)-R) was identified as the major purinoceptor regulating ciliary beat frequency (CBF); UTP (EC(50) = 4.7 microM), ATP, and adenosine-5'-O-(3-thiotriphosphate) elicited similar maximal responses, approximately twofold over baseline. ATP, however, elicited a post-peak sustained plateau in CBF (1.83 +/- 0.1-fold), whereas the post-peak CBF response to UTP declined over 15 min to a low-level plateau (1.36 +/- 0.16-fold). UDP also stimulated ciliary beating, probably via P2Y(6)-R, with a maximal effect approximately one-half that elicited by P2Y(2)-R stimulation. Not indicated were P2Y(1)-R-, P2Y(4)-R-, or P2Y(11)-R-mediated effects. A(2B)-receptor agonists elicited sustained responses in CBF approximately equal to those from UTP/ATP [5'-(N-ethylcarboxamido)adenosine, EC(50) = 0.09 microM; adenosine, EC(50) = 0.7 microM]. Surprisingly, ADP elicited a sustained stimulation in CBF. The ADP effect and the post-peak sustained portion of the ATP response in CBF were inhibited by the A(2)-R antagonist 8-(p-sulfophenyl)theophylline. Hence, ATP affects ciliary activity through P2Y(2)-R and, after an apparent ectohydrolysis to adenosine, through A(2B)AR.

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Sinonasal undifferentiated carcinoma is a relatively rare and aggressive malignancy of the nose and paranasal sinuses. It is often difficult to distinguish from other poorly differentiated sinonasal malignancies. Since it was first described in 1986, advances have been made in the understanding of the histology and immunohistochemical markers of sinonasal undifferentiated carcinoma, but the treatment options and prognosis remain poor. Presenting signs and symptoms, patient demographics, risk factors as well as immunohistochemical findings are reviewed. While no treatment is standard for sinonasal undifferentiated carcinoma, several modalities and combinations including chemotherapy, radiation, and surgery have been used with varied success. The several case series reported are examined and future directions of therapy discussed.

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There are many known causes of vertigo, but many cases remain unexplained. Sound-induced, pressure-induced, or positional vertigo caused by bony dehiscence of the superior semicircular canal into the middle cranial fossa is a newly described etiology of vertigo. Three case studies of patients with CT evidence and surgical confirmation of bony dehiscence of the superior semicircular canal with variable presentations are described. The history, symptoms, CT findings, vestibular studies, and method of surgical repair are presented. Two patients had disabling vertigo and one had no vestibular symptoms. All underwent exploration via a middle cranial fossa approach with repair of the dehiscence. The bony dehiscence of the superior semicircular canal of the asymptomatic patient was identified and closed at the time of an encephalocele repair procedure. All patients did well postoperatively and both patients with vertigo improved. Bony dehiscence of the superior semicircular canal may cause vertigo or be asymptomatic and should be added to the differential diagnosis of vertigo.

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Gastroesophageal reflux disease (GERD) is the abnormal retrograde flow of gastric contents into the esophagus. While disorders of the esophagus related to GERD are fairly well characterized, supraesophageal symptoms may be nonspecific and easily missed. Fewer than half of the patients with otolaryngologic complications of reflux exhibit the classic findings of heartburn and regurgitation. GERD has been implicated in a broad range of disorders including laryngitis, chronic hoarseness, globus pharyngeus, laryngeal carcinoma, cricopharyngeal hypertension, Zenker's diverticulum, and chronic cough. A high index of suspicion is essential for timely diagnosis and treatment of the otolaryngologic manifestations of GERD.

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Neck dissection is a surgical procedure used in the diagnosis and treatment of head and neck cancer. The neck dissection involves excising the lymph nodes in specified regions of the neck with or without removing the sternocleidomastoid muscle, the internal jugular vein, and the spinal accessory nerve. The removal of cervical lymph nodes not only aids in staging the malignancy but also treats the nodal disease and dictates further treatment such as radiation therapy. Because of the proximity of vital structures, certain risks and complications are inherent to this operation. The prevention, recognition, and treatment of early and late complications of neck dissection are discussed.

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