A report of oral extramedullary acute myeloid leukaemia (AML) in an 8-year-old girl with newly diagnosed AML-M4Eo

Acute myeloid leukaemia (AML), characterized by proliferation of immature neoplastic myeloid cells, is uncommon in childhood. We present a case of an 8-year-old girl with AML-M4Eo who had an extramedullary leukaemic tumour in the oral cavity.

Orbital abscess as a complication of odontogenic infection. A case report and review of the literature

Orbital abscess is a rare complication of odontogenic infection. This report describes a case of an orbital abscess in a 42-year-old HIV-seropositive woman who developed this condition as a complication by direct spread via the maxillary sinus of a dento-alveolar abscess of the maxillary first premolar, resulting in the loss of her eye.

The association between human herpes viruses and periodontal disease, part 2

The role of herpesviruses in the aetiopathogenesis of periodontal diseases is uncertain. While their role in the initiation and progression of periodontal disease has not been established, the increased levels of herpesvirus gene products in periodontally diseased sites--compared to that in clinically healthy sites--and their association with elevated levels of periodontopathic bacteria points to a possible coactive role of the herpesviruses with the bacteria. The available data regarding the relationship between herpesviruses and the periodontal disease status, as well as the possible mechanisms that might enable herpesviruses to influence the pathogenesis of periodontal diseases, are discussed.

Necrotizing gingivitis of Kaposi sarcoma affected gingivae

Necrotizing gingivitis and oral Kaposi sarcoma are common concomitants of HIV infection and both are regarded as indicators of HIV infection. Their simultaneous appearance in an HIV seropositive subject therefore, should be relatively common; but other reports documenting such cases could not be found. This article documents an uncommon case of necrotizing gingivitis superimposed on Kaposi sarcoma-affected gingiva, occurring in a patient with chronic periodontitis. The nature of necrotizing gingivitis and Kaposi sarcoma and the possible differential diagnosis of the periodontal attachment loss are discussed.

Tooth mobility after periodontal surgery

Changes in tooth mobility after surgical crown lengthening procedures were examined with a modern electro-mechanical instrument (Periotest) in a total of 37 teeth in 14 patients between the ages of 18 and 55 years. Seven teeth were incisors, three canines, thirteen pre-molars and fourteen were molars. Periotest values, probing depths, bleeding indices and plaque indices were recorded after the initial preparation stage of the periodontal treatment, and further Periotest values and plaque and bleeding indices were recorded at intervals up to 3 months after surgery. In each category of teeth there was a progressive increase in tooth mobility starting immediately after surgery and peaking about the seventh day. The mobility then declined steadily to approach the base line again at about 3 months. There were statistically significant differences in mobility after surgery between tooth types (p < 0.01). Gender and age did not significantly affect the values. The pattern of post-surgical tooth mobility can be closely correlated with the known biological events of post-surgical healing.

Encephalotrigeminal angiomatosis

We report an unusual case of encephalotrigeminal angiomatosis in which the facial and oral angioma was bilateral, and several teeth were congenitally absent. The developmental nature of the anomaly is reviewed. Encephalotrigeminal angiomatosis is commonly referred to as the Sturge-Weber syndrome, after Sturge and Weber who first described this affliction in 1879. The main clinical features of this syndrome are 1. venous angiomatosis of the leptomeninges of the cerebral-cortex, usually unilaterally 2. ipsilateral facial angiomatosis that often follows in outline the distribution of the trigeminal nerve (Fig 1) 3. ipsilateral gyriform calcification of the cerebral cortex 4. epileptic convulsions (contralateral focus) or other seizures 5. ocular defects (choroidal angioma, glaucoma hemianopia) 6. mental retardation 7. contralateral hemiplegia 8. obesity 9. oral mucosal and gingival involvement. Other less typical features are 1. association with hypomelanosis of 1 to 10 2. leptomeningeal angioma contralateral to the facial nevus 3. leptomeningeal angioma without facial vascular naevus 4. association with gastro intestinal hemorrhage 5. paranasal sinus enlargement. This syndrome that affects males and females equally, is a rare congenital disorder, apparently hamartomatous in nature, from persistence of a primitive embryonal vascular plexus. During the sixth week of intra-uterine life this plexus develops around the cephalic portion of the neural tube and under the ectoderm in the region destined to become facial skin. In the Sturge-Weber syndrome, the vascular plexus fails to regress, as is normal during the ninth week, resulting in angiomatosis of the related tissues. Variation in the degree of persistence or regression of the vascular plexus accounts for unilaterality or bilaterality of involvement, and also for an incomplete syndrome in which the leptomeninges, but not the facial tissues are affected. Leptomeningeal angiomatosis is the primary abnormality of encephalotrigeminal angiomatosis, all other features of the syndrome probably being secondary to this. Calcification of the cortex is a poorly understood phenomenon which may result from stasis of blood in the angioma, associated with altered local metabolism. Epilepsy and other neurological seizures, and mental retardation are probably, in their turn, secondary to the cortical calcification. The most striking clinical feature of the Sturge-Weber syndrome is the facial vascular naevus which generally follows the distribution of innervation of one or more divisions of the trigeminal nerve, whence the term encephalotrigeminal angiomatosis. However, the naevus may be more extensive, down the neck and even onto the chest. The oral tissues underlying the affected facial tissues are invariably also angiomatous and may be considerably enlarged as a result. Alterations in eruption of teeth have also been noted. Histologically, affected soft tissues are very vascular, resembling a pyogenic granuloma or a capillary, or cavernous hemangioma. Yukna, Cassingham and Carr noted that affected bone was partially replaced by a delicate fibrous tissue containing thin-walled vascular spaces. Neither inflammatory cells, nor fatty or haemopoietic marrow was noted.

Endothelin-converting enzyme-1 (ECE-1) is a downstream target of the homeobox transcription factor Nkx2-5

The homeobox transcription factor Nkx2-5 and the zinc metalloprotease endothelin-converting enzyme-1 (ECE-1) are essential for cardiac development. Here, we demonstrate for the first time a functional link between Nkx2-5 and ECE-1. In transiently transfected rat H9c2 cardiomyoblasts, the alternative promoters specific for ECE-1a, ECE-1b, and ECE-1c are activated by Nkx2-5 coexpression. Lack of a consensus sequence for Nkx2-5 binding within the ECE-1c promoter and mutational analyses of Nkx2-5 consensus sequences identified in the ECE-1a and ECE-1b promoters, respectively, reveal an indirect mechanism of activation that is supported by gel shift assays. Furthermore, we have evidence of an additional direct activation mechanism of the ECE-1b promoter by Nkx2-5. With the use of RNase protection assay, Northern blot, and real-time PCR, the activating effect of Nkx2-5 on mRNA expression of ECE-1 isoforms was confirmed in the chromatin context of H9c2 and endothelial EA.hy926 cells, respectively, by stable Nkx2-5 overexpression. The interaction presented in this work provides a possible explanation for distinct phenotypic aspects of patients carrying mutations in the Nkx2-5 gene and may also be of significance for the pathophysiology of heart failure.

Characterization of the c-specific promoter of the gene encoding human endothelin-converting enzyme-1 (ECE-1)

Human ECE-1 is expressed in four isoforms with different tissue distribution and its mRNA and protein levels are altered under certain pathophysiological conditions. To investigate the transcriptional regulation of ECE-1, we studied the regulatory region of ECE-1c, the major ECE-1 isoform. A genomic clone comprising the complete human ECE-1 gene including the putative ECE-1c-specific promoter was obtained. Up to 968 bp upstream of the putative c-specific translation initiation start codon and several serial deletion mutants were subcloned into a reporter vector and transfected into endothelial (BAEC, EA.hy926, ECV304) and epithelial (MDA MB435S, MCF7) cells, showing very strong promoter activity in comparison to the SV40 promoter and to the previously described ECE-1a and 1b promoters. Transfection of serial deletion mutants indicated two positive regulatory regions within the promoter (-142/-240 and -240/490) likely involved in binding GATA and ETS transcription factors. RNase protection assay (RPA) and 5'-RACE revealed multiple transcriptional start sites located at about -110, -140 and -350 bp. Site-directed mutagenesis demonstrated a crucial role for the E2F cis-element for basal ECE-1c promoter activity. Additionally, we found a correlation between isoform-specific ECE-1 mRNA levels and corresponding ECE-1a, 1b, 1c promoter activities.

Cloning and functional characterization of the bovine endothelin-converting enzyme-1a promoter

Endothelin-converting enzyme-1 (ECE-1) mRNA is expressed in three isoforms, termed a, b, and c, originating from alternative promoters. In cultured bovine aortic endothelial cells, we detected mRNA isoform expression of ECE-1a and ECE-1b/c, respectively. Investigating transcriptional mechanisms of bovine endothelial ECE-1a expression in more detail, we identified multiple transcription start sites localized 120-415 nucleotides upstream from the presumptive translation start codon by RNase protection assay and 5' RACE. Using luciferase reporter gene assays we found that 1.4 kb of the 5' untranslated region showed strong promoter activity in endothelial cells. Sequence analysis revealed 71% overall homology of the bovine ECE-1a promoter with its human homologue. The proximal 680 base pair promoter region was shown to contain cis elements that are sufficient for basal and serum-induced transcriptional activation.

Antibiotic prophylaxis in periodontal surgery. A retrospective study

Antibiotics are frequently used in periodontal and minor oral surgery to prevent complications. The potential disadvantages of antibiotic prophylaxis are well documented. This study compares the incidence of complications for procedures performed with and without antibiotic prophylaxis. The clinical records of 1499 patients who received treatment at a university teaching hospital were reviewed. 1078 surgical procedures were done on 596 patients. 895 surgical procedures were done without prophylactic antibiotics, with 17 complications (1.9 per cent). 183 procedures were done using antibiotic prophylaxis, with 1 complication (0.55 per cent). The difference between the incidences of complications in the two groups was not statistically significant (P < 0.001). In view of the questionable benefits and potential disadvantages of using antibiotics, their routine use during or following periodontal surgery must be questioned.