A treatment planning comparison of photon stereotactic ablative radiotherapy and proton beam therapy for the re-irradiation of pelvic cancer recurrence.

BACKGROUND: Patients who experience a pelvic cancer recurrence in or near a region that received initial radiotherapy, typically have few options for treatment. Organs at risk (OAR) have often reached their dose constraint limits leaving minimal dose remaining for standard re-irradiation (reRT). However, photon based stereotactic ablative radiotherapy (SABR) has been utilised for reRT with promising initial results although meeting OAR constraints can be challenging. Proton beam therapy (PBT) could offer an advantage. MATERIALS AND METHODS: SABR plans used for treatment for ten pelvic reRT patients were dosimetrically compared to PBT plans retrospectively planned using the same CT and contour data. PBT plans were created to match the CTV dose coverage of SABR treatment plans with V100% ≥95%. An 'as low as reasonably achievable' approach was taken to OAR tolerances with consideration of OAR dose from the initial radiation (using equivalent dose in 2 Gy fractions). RESULTS: Dosimetric comparison of relevant OAR statistics showed a decrease in OAR dose using PBT over SABR in all patients, with equivalent target coverage. The largest statistically significant reduction was seen for the colon D0.5 cm3 with a median reduction from 13.1 Gy to 5.9 Gy. There were statistically significant dose reductions in the median dose to small bowel, sacral plexus and cauda equina. CONCLUSION: PBT has the potential for significant dose reductions for OARs in the pelvic reRT setting compared to SABR. However, it remains unclear if the magnitude of these OAR dose reductions will translate into clinical benefit.

Three decades of occupational individual monitoring at the University of São Paulo.

As the ionizing radiation to which workers are exposed is related to possible harmful biological effect, its dose evaluation gains relevance. Although the effects of low doses are still controversial, the radiation protection authorities assume that any dose of ionizing radiation is potentially harmful to the human health and adopt the linear non-threshold model for the dose-effect relation. The Dosimetry Laboratory of the Institute of Physics of the University of São Paulo performs the external individual monitoring of workers exposed to X- and gamma-rays since 1981, with the technique of thermoluminescence. Currently, ~500 badges are provided to the university professionals mostly working in research laboratories and hospitals. Data of individual annual dose equivalent collected from 1995 to 2015 and the performance of the monitoring service are presented in this paper.

Genomic duplication in Dyggve Melchior Clausen syndrome, a novel mutation mechanism in an autosomal recessive disorder.

BACKGROUND: Dyggve Melchior Clausen syndrome (DMC) is a severe autosomal recessive skeletal dysplasia associated with mental retardation. Direct sequencing of genomic DNA has identified causative mutations in the gene Dymeclin (chromosome 18q12-21), with the majority predicting the generation of a truncated protein product. OBJECTIVE: To carry out molecular genetic studies in three DMC kindreds. RESULTS: Two novel nonsense mutations and two complex genomic duplication events resulting in exon repetition were identified. CONCLUSIONS: Exon dosage assessment or mRNA analysis, in addition to direct genomic DNA sequencing, should be employed in the investigation of DMC affected individuals. Genomic duplication may be the causative mutation mechanism in other autosomal recessive disorders.

Activating and inactivating mutations in the human GNAS1 gene.

GNAS1 on chromosome 20 is a complex locus, encoding multiple proteins, of which G(s)alpha, the alpha-subunit of the heterotrimeric stimulatory G protein G(s), is of particular interest clinically. Amino acid substitutions at two specific codons lead to constitutive activation of G(s)alpha. Such gain-of-function mutations are found in a variety of sporadic endocrine tumors and in McCune-Albright syndrome, a sporadic condition characterized by multiple endocrine abnormalities. Heterozygous loss of G(s)alpha function results in the dominantly inherited condition, Albright hereditary osteodystrophy (AHO). Here we present a review of published GNAS1 mutations and report 19 additional mutations, of which 15 are novel. A diverse range of inactivating mutations has been detected, scattered throughout the gene but showing some evidence of clustering. Only one, a recurring 4 bp deletion in exon 7, could be considered common among AHO patients. The parental origin of the mutation apparently determines whether or not the patient shows end-organ resistance to hormones such as parathyroid hormone. G(s)alpha is biallelically expressed in all tissues studied to date and thus there is no direct evidence that this transcript is imprinted. However, the recent identification of other imprinted transcripts encoded by GNAS1 and overlapping G(s)alpha, together with at least one imprinted antisense transcript, raises intriguing questions about how the primary effect of mutations in GNAS1 might be modulated.

Class-specific antibodies to Streptococcus mutans in human serum, saliva and breast milk.

Previous techniques used for the detection and quantitation of antibodies in body fluids may be inappropriate where only small volumes are available, or may not be sensitive enough to detect low levels of specific antibodies. An indirect ELISA technique has successfully been employed to estimate class-specific antibody levels to Streptococcus mutans in serum and secretions in a group of mothers and their neonates, and an attempt has been made to relate such levels to the presence or absence of active caries in the mothers. A high maternal serum IgG antibody level appears to exert a protective effect against dental caries. Antibody levels in maternal saliva and colostrum/breast milk showed no differences between the 2 groups. The presence of active caries in mothers was associated with an elevated IgA antibody level in neonatal saliva. Although ELISA permitted the detection of low levels of antibody in the small volumes of neonatal saliva collected, a further increase in sensitivity and specificity of the assay would be advantageous.

SHH mutation is associated with solitary median maxillary central incisor: a study of 13 patients and review of the literature.

Solitary median maxillary central incisor (SMMCI) or single central incisor is a rare dental anomaly. It has been reported in holoprosencephaly (HPE) cases with severe facial anomalies or as a microform in autosomal dominant HPE (ADHPE). In our review of the literature, we note that SMMCI may also occur as an isolated finding or in association with other systemic abnormalities. These anomalies include short stature, pituitary insufficiency, microcephaly, choanal atresia, midnasal stenosis, and congenital nasal pyriform aperture stenosis. SMMCI can also be a feature of recognized syndromes or associations or a finding in patients with specific chromosomal abnormalities. We performed a molecular study on a cohort of 13 SMMCI patients who did not have HPE. We studied two genes, Sonic Hedgehog (SHH) and SIX3, in which mutations have been reported in patients showing SMMCI as part of the HPE spectrum. A new missense mutation in SHH (I111F), segregating in one SMMCI family, was identified. Our results suggest that this mutation may be specific for the SMMCI phenotype since it has not been found in the HPE population or in normal controls. Published 2001 Wiley-Liss, Inc.

Prevalence and intraoral distribution of Candida albicans in Sjögren's syndrome.

An imprint culture technique has been employed to study the prevalence and intraoral distribution of Candida albicans in 16 patients with Sjögren's syndrome and in 16 healthy controls matched for age, sex, and dental status. The prevalence and intraoral density of C. albicans was found to be significantly higher at almost all sites in the Sjögren's patients than in the controls. The distribution of candida was also altered, being significantly higher in the floor of the mouth and anterior labial sulcus in the Sjögren's group. There was an approximate inverse relationship between candida populations and rate of salivary flow. Mean candida densities were found to be significantly higher in those Sjögren's patients with detectable serum rheumatoid factor in the serum. However, patients with primary Sjögren's syndrome had significantly higher mean candida densities compared with patients with secondary Sjögren's syndrome.

Candidal infections and populations of Candida albicans in mouths of diabetics.

The prevalence of oral candidosis and the frequency of isolation of Candida albicans and its density and distribution have been determined in the mouths of 50 patients with diabetes mellitus and 50 healthy volunteers matched for age, sex, dental status and smoking habits. Three of the diabetic patients were found to have a chronic oral candidosis. According to an imprint culture technique, the oral carrier rate and density of C albicans were both higher in the diabetic group as a whole than in the control subjects. Smoking was associated with an increased prevalence of the yeast in diabetes mellitus. Diabetics wearing dentures had higher candidal density than those without a prosthesis. No differences in candidal status could be detected according to the degree of control of diabetes, mode of treatment, duration of diabetes or the patient's age. Local factors such as smoking and the presence of dentures, particularly when worn continuously, interact with diabetes mellitus in promoting candidal colonisation of the mouth. Attention to these predisposing factors could reduce the incidence of thrush in diabetics.

Comparison of identification methods for oral asaccharolytic Eubacterium species.

Thirty one strains of oral, asaccharolytic Eubacterium spp. and the type strains of E. brachy, E. nodatum and E. timidum were subjected to three identification techniques--protein-profile analysis, determination of metabolic end-products, and the API ATB32A identification kit. Five clusters were obtained from numerical analysis of protein profiles and excellent correlations were seen with the other two methods. Protein profiles alone allowed unequivocal identification.

An improved medium for isolation of Streptococcus mutans.

A medium based upon tryptone, yeast extract, cystine (TYC) agar and incorporating bacitracin and sucrose has been evaluated for selective isolation of Streptococcus mutans. The effect of varying the concentrations of sucrose and bacitracin on the recovery of two standard strains was investigated. Growth of S. mutans NCTC 10449 was significantly inhibited by increasing concentrations of sucrose but was not affected by bacitracin; the reverse was seen with S. sobrinus strain 6715. The best compromise between recovery of the streptococci and growth of other organisms was obtained with a final sucrose concentration of 20% and bacitracin 0.2 units/ml. In comparison with three other selective media, this medium gave the highest recovery rate of standard strains, indicating that it is superior to mitis-salivarius bacitracin (MSB) agar for the recovery of S. mutans from saliva.

Solitary fibrous tumour of the oral cavity: report of two cases.

The solitary fibrous tumour is an uncommon, benign neoplasm of adults involving the pleura. It is now recognised to occur in extrapleural sites. Only a limited number of cases have been reported in the oral cavity. This paper reports two further cases, which presented as clinically benign masses in the palate and buccal mucosa respectively.

Persistence of IgA in neonatal saliva following breast feeding.

Breast milk antibodies have been shown to persist in the mouths of neonates for some hours following feeding. The decrease in concentration following a feed probably reflects the flushing action of salivary flow combined with swallowing.

Hereditary gingival fibromatosis associated with hearing loss and supernumerary teeth--a new syndrome.

Hereditary gingival fibromatosis can occur as an isolated trait or as part of a syndrome. We report on three generations of one family featuring an autosomal dominant syndrome with variable expression of gingival fibromatosis with associated hearing deficiencies, hypertelorism, and supernumerary teeth. We propose that this represents a new syndrome within the spectrum of those including gingival enlargement.

Amelogenesis imperfecta phenotype-genotype correlations with two amelogenin gene mutations.

Amelogenin, the predominant matrix protein in developing dental enamel, is considered essential for normal enamel formation, but its exact functions are undefined. Mutations in the AMELX gene that encodes for amelogenin protein cause X-linked amelogenesis imperfecta (AI), with phenotypes characterized by hypoplastic and/or poorly mineralized enamel. Eight different AMELX deletion and substitution mutations have been reported to date. The purpose here was to evaluate the genotype and phenotype of two large kindreds segregating for X-linked AI. Phenotypically affected males in family 1 had yellowish-brown, poorly mineralized enamel; those in family 2 had thin, smooth, hypoplastic enamel. Heterozygous females in both kindreds had vertical hypoplastic grooves in their enamel. DNA was obtained from family members; exons 1-7 of AMELX were amplified and sequenced. Mutational analysis of family 1 revealed a single-base-pair change of A-->T at nucleotide 256, resulting in a His-->Leu change. Analysis of family 2 revealed deletion of a C-nucleotide in codon 119 causing a frameshift alteration of the next six codons, and a premature stop codon resulting in truncation of the protein 18 amino acids shorter than the wild-type. To date, all mutations that alter the C-terminus of amelogenin after the 157th amino acid have resulted in a hypoplastic phenotype. In contrast, other AMELX mutations appear to cause predominantly mineralization defects (e.g. the mutation seen in family 1). This difference suggests that the C-terminus of the normal amelogenin protein is important for controlling enamel thickness.

Multisite point-of-care potassium testing for patient-focused care.

In the past two decades, a dominant paradigm has been the main laboratory, which is often located far from the patient and characterized by slow response times. The invention of whole blood biosensors and the innovation of point-of-care testing have initiated a paradigm shift in diagnostic medicine that supports the trend toward patient-focused care. The objective of this study was to compare point-of-care potassium testing performed with a handheld potassium analyzer (STAT K, PDx Technologies Inc, Westlake Village, Calif) in the cardiac and intensive care units with potassium measurements obtained similarly in the main laboratory. Two critical care nurses performed point-of-care testing for critically ill patients. In a series of 56 specimens, the mean +/- SD potassium levels were 3.91 +/- 0.53 and 3.94 +/- 0.57 mmol/L when testing was performed at the bedside and in the main laboratory, respectively. The mean paired difference, -0.03 mmol/L, between point-of-care and main laboratory results was not statistically or clinically significant. Point-of-care potassium testing is accurate and precise, as well as clinically efficient for use in patient-focused care settings.

Frequency and density of yeasts in the mouths of malnourished children.

The prevalence and density of yeasts and Candida albicans on the buccal mucosa and dorsum of the tongue have been assessed in 106 children in Crossroads squatter camp, South Africa. They were divided into a malnourished and a control group on the basis of an age/weight chart. No differences were found in yeast prevalence and density in the two groups. However, malnourished children more frequently had a mucosal density of yeasts, and particularly C. albicans, exceeding the upper limit normally found in health, in the absence of clinical infection. Some evidence was found to suggest that yeast density might be influenced by sex as well as nutritional status.

Juvenile mandibular chronic osteomyelitis: a distinct clinical entity.

Sclerosing osteomyelitis of the mandible is an uncommon disease of unknown aetiology. A series of eight female children (6 to 12 years old) with a distinct mandibular inflammatory disease were studied. Each presented with pain and a recurrent soft tissue swelling overlying a predominantly unilateral mandibular enlargement. On imaging, this deformity demonstrated a mixture of patchy sclerosis and radiolucency. A raised erythrocyte sedimentation rate was the only consistent serological finding. Treatment varied from symptomatic control with non-steroidal anti-inflammatory medication, to surgical management that included decortication and contouring and, in one case, resection with reconstruction. A potential protocol for treatment of this disease is given. The early age of onset of the disease process and the uniformity of the features distinguish this condition from other groups of disorders that, previously, have been collectively designated as chronic diffuse sclerosing osteomyelitis. It is proposed that this inflammatory disease of mandibular bone, in the paediatric patient, should be regarded as a separate clinical entity: 'juvenile mandibular chronic osteomyelitis'.

Solitary median maxillary central incisor, short stature, choanal atresia/midnasal stenosis (SMMCI) syndrome.

This article describes a series of 21 consecutive cases, each involving a solitary median maxillary central incisor; the patients were seen in the Department of Dentistry or the Victorian Clinical Genetics Unit, Murdoch Institute, at the Royal Children's Hospital, Melbourne, from 1966 to 1997. The spectrum of anomalies and associated features present in these cases--solitary median maxillary central incisor, choanal atresia, and holoprosencephaly--is described, and the literature related to the features, including genetic studies in these conditions, is reviewed. We relate our findings in these cases to current knowledge of developmental embryology. It is hoped that the findings, together with our interpretation of them, will help to clarify understanding of solitary median maxillary central incisor syndrome. This syndrome was previously considered a simple midline defect of the dental lamina, but it is now recognized as a possible predictor of holoprosencephalies of varying degrees in the proband, in members of the proband's family, and in the family's descendants.

Massive giant cell epulis in a child with familial cyclic neutropenia.

A case of a boy with familial cyclic neutropenia and a large giant cell epulis is reported. The clinical management is described and the significance of the neutropenia in relation to subsequent infection of the epulis is discussed.

Clinico-pathological conference 2002.

INTRODUCTION: Six cases are reported, each presented at the 11th Biennial Congress of the International Association of Oral Pathologists as an instructive case for differential diagnosis on the basis of clinical, imaging or histological features. CLINICAL PICTURE: Case diagnoses included a large, possibly intraosseous, myofibroma presenting with an oral mass; Langerhans cell histiocytosis with facial skin lesions; an intraosseous vascular hamartoma of the maxilla with worrying radiological features; an unusual mixed radiolucency of the jaw caused by cemento-ossifying fibroma; an osteosarcoma of the posterior mandible causing a well-defined radiolucency and an intraoral squamous cell carcinoma in a child.