Potential pathogenic mechanisms of periodontitis associated pregnancy complications.

During normal pregnancy, maternal hormones and locally acting cytokines play a key role in regulating the onset of labor, cervical ripening, uterine contraction, and delivery. Maternal infections during pregnancy have been demonstrated to perturb this normal cytokine and hormone-regulated gestation, sometimes resulting in preterm labor, preterm premature rupture of membranes, and preterm low birth weight (PLBW), i.e., < 2,500 g and < 37 weeks of gestation. Our research focus has been to determine whether periodontal infections can provide sufficient challenge to the mother to trigger PLBW. New experiments from 48 case-control subjects have measured gingival crevicular fluid (GCF) levels of PGE(2) and IL-1-beta to determine whether mediator levels were related to current pregnancy outcome. In addition, the levels of 4 periodontal pathogens were measured by using microbe-specific DNA probes. Results indicate that GCF-PGE(2) levels are significantly higher in PLBW mothers, as compared with normal birth weight (NBW) controls (131.4 +/- 21.8 vs. 62.6 +/- 10.3 [mean +/- SE ng/mL], respectively, at P = 0.02). Furthermore, within primiparous PLBW mothers, there was a significant inverse association between birth weight (as well as gestational age) and GCF-PGE(2) levels at P = 0.023. These data suggest a dose-response relationship for increasing GCF-PGE(2) as a marker of current periodontal disease activity and decreasing birth weight. Microbial data indicate that 4 organisms associated with mature plaque and progressing periodontitis--bacteroides forsythus, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Treponema denticola--were detected at higher levels in PLBW mothers, as compared to NBW controls. These data suggest that biochemical measures of maternal periodontal status and oral microbial burden are associated with current PLBW.

Development of in vivo gene therapy for hearing disorders: introduction of adeno-associated virus into the cochlea of the guinea pig.

Gene therapy is currently being used to treat many disorders including cancer, viral infection and the degenerative and fatal diseases of the cardiovascular and the central nervous systems. However, the potential use of gene therapy for alleviation of hearing impairment has not been investigated despite the absence of effective therapy for most forms of inherited hearing disorders. The purpose of this study was to assess the feasibility of introducing genetic material directly into the peripheral auditory system using adeno-associated virus (AAV) as the transfection vector and Hartley guinea pigs as the animal model. Approximately 10(5) particles of AAV containing the bacterial beta-galactosidase (beta-gal) sequence with Ad 2 major late promoter were infused into the cochlea of the animal with the aid of an osmotic minipump. Animals were killed after 2 weeks. Two Hartley guinea pigs with intracochlear saline infusion and four unoperated (nonperfused) animals served as negative controls. Both, the infused and the contralateral, non-infused cochleae were harvested from each animal, decalcified, and embedded in paraffin. Sections, 8 microns in width, were cut from the embedded cochleae and assayed for beta-gal expression via immunohistochemistry. Animals perfused with AAV showed intense immunohistochemical reactivity in the spiral limbus, spiral ligament, spiral ganglion cells and the organ of Corti in the perfused cochlea and a much weaker staining but with similar pattern in the contralateral ear. Cochleae from saline-infused and unoperated animals were devoid of the DAB stain. This study demonstrates for the first time in vivo expression of a foreign gene within the mammalian inner ear resulting from its localized, AAV-mediated introduction. The ability to introduce and stably express exogenous genetic material in the peripheral auditory system will have both experimental and therapeutic benefits. These results lay the groundwork for future studies assessing the potential use of gene therapy for alleviation of hearing impairment.

Is pre-operative patient assessment effective? A prospective trial of 100 patients.

The working patterns of clinical postgraduate trainees are being scrutinised in preparation for the implementation of new, structured and shortened postgraduate specialist training programmes. Current practice in the National Health Service dictates, in all branches of surgery, the evaluation of elective admissions undergoing procedures under general anaesthetic by a junior trainee (SHO or HO) who then arranges the appropriate preoperative investigations. This doctor acts as a "generalist' in that he is primarily concerned with the patient's general fitness for the operation as well as with the specific condition to be treated. The anaesthetist also evaluates the patient prior to the operation. In his case his sole concern is to whether or not the patient is fit for a general anaesthetic. This prospective study investigated the extent of duplication in preoperative elective patient assessment by both the otolaryngology trainee and the anaesthetist in order to answer the question: are both assessments necessary? The medical records of 100 consecutive adult elective admissions to the Leicester Royal Infirmary Otolaryngology Department which provides inpatient services to a catchment population of 900,000 were reviewed. The case histories obtained by clinicians blind to the study were classified as positive or negative for relevant features. The case histories obtained by the otolaryngology trainee and anaesthetist showed a level of disagreement which was 9 per cent greater than chance. It appears that there is a low level of duplication in preoperative elective otolaryngology patient assessment and both otolaryngology trainee and anaesthetic examination are of value.

Identifying losing sites at periodontal reevaluation.

Our present method for clinical evaluation of marginal periodontal tissues involves examination for bleeding and suppuration and the measurement of probing depth. There is little doubt that this method provides useful guidelines for evaluation of the overall periodontal status of dentitions. On an individual-site basis, however, it has limitations in the identification of locations prone to disease progression. So far, there is no reliably clinical, microbiologic, or other method to predict or identify sites with disease activity (i.e., ongoing loss of attachment). Therefore, there are no clear guidelines for distinguishing between active and arrested lesions. A treatment resulting in a plaque-free mouth with nonbleeding and shallow probing depths throughout the dentition will reduce the risk of residual, active disease. Such a result, although desirable, is not realistic for many patients. Therefore, the clinician is faced with the delicate task of evaluating sites with various grades of involvement using current clinical methods of examination.

Tonsil surface and core cultures in recurrent tonsillitis: prevalence of anaerobes and beta-lactamase producing organisms.

The bacterial flora of the tonsil surface and core was compared in patients suffering from recurrent tonsillitis. Surface swabs and tonsil core tissues were received as paired samples from 50 patients admitted for elective tonsillectomy. Analysis of paired samples from individual patients revealed differences in the bacterial flora of the tonsil core and the tonsil surface. Of 366 aerobic isolates, 30% grew from the surface alone, 26% from the core only and 44% from both sites. Of 290 anaerobic isolates, 35% grew from the surface alone, 33% from the core only and 31% from both sites. The total number of isolates from surface and core samples was similar (average 9.2 and 8.8, respectively). The range of species isolated was also similar for both surface and core samples, as was the proportion of organisms producing beta-lactamase from each site (10.7% and 9.5%, respectively). Eighty-two percent of patients carried beta-lactamase-producing organisms on either the tonsil surface or in the core tissue. A surface swab does not reliably reflect the types of organisms present in the tonsil core in individual patients. Anaerobes are a major component of tonsil surface and core bacterial flora in patients with recurrent tonsillitis. The high carriage rate of beta-lactamase-producing organisms in the tonsils should be considered when selecting antimicrobial therapy for persistent or recurrent tonsillitis.

Salivary terminal duct carcinoma.

We report two cases of terminal duct carcinoma of the minor salivary glands. The histological features, biological behaviour, treatment and the long-term management are described.

Metabolic stridor: bilateral vocal cord abductor paralysis secondary to hypokalaemia?

A previously unreported association between bilateral abductor paralysis and hypokalaemia is reported in a patient presenting with stridor. Both the stridor and the bilateral abductor paralysis gradually resolved as the serum potassium was corrected. A casual link is suggested though the mechanism is unclear.

Congenital cholesteatoma presenting as a post-auricular mass.

Congenital cholesteatoma usually presents as either a conductive deafness or as a facial palsy. We report a case which presented as a post-auricular mass. It is important to recognize the possibility that the disease may present in this way when considering the management of such a mass.