Oral complications of Type 1 diabetes mellitus in a non-smoking population

Type 1 diabetes mellitus (T1DM) is a complex metabolic condition that results in hyperglycemia due to insulin deficiency (Daneman, 2006). Diabetes has a range of effects on almost every system in the body including the kidneys, the eyes, the cardiovascular system, the genito-urinary system, the gastro-intestinal system and the nervous system (Daneman, 2006). The effects of this ondition are widespread and have a significant impact both on life expectancy and the quality of life of individuals suffering from diabetes (Scottish Diabetes Survey Monitoring Group, 2011). The impact of diabetes on oral health has been investigated over many decades, however, the conclusions have been varied and study design has not always been adequate (Mealey et al., 2006; Khader et al., 2006; Chávarray et al., 2009). Research presented in this thesis is largely the result of a cross-sectional clinical study examining the oral cavities of non-smoking T1DM patients, funded by the Chief Scientist Office of the Scottish Government. The clinical part of the study took place between January 2006 and May 2009 in Glasgow Dental Hospital. Chapter one provides an introduction and narrative review on the subject of T1DM, periodontal disease, and the various other reported oral manifestations of diabetes mellitus. The methods for measuring general and oral health related quality of life outcomes are also discussed. Chapter one reveals some of the inadequacies of studies nvestigating the link between T1DM and oral disease to date and ontextualises the studies presented in this thesis. Chapter two presents the main periodontal findings of a large cross-sectional study. 112 non-diabetic subjects and 203 subjects with type 1 diabetes were examined. 203 diabetic patients were divided into well controlled and poorly controlled groups based on their average blood sugar levels over the previous two years. 169 were poorly controlled. (PCD). Those with T1DM, (especially those with poor glycaemic control) had a greater extent and severity of periodontitis than those without diabetes. There was also some evidence that never smoking T1DM patients were more likely to have periodontal disease than non-diabetic subjects. The odds ratio (OR) was 1.43 [0.74 to 2.75] (p = 0.29) for all T1DM patients and 1.58 [0.75 to 3.33] (p = 0.23) for PCD. This difference remained even after the multivariable analysis took into account age, gender and lifestyle including: body mass index of the subject; whether they had smoked in the past; whether they attended a dentist; their level of education and how deprived the area they lived in was. Chapter three presents an analysis of the impact of age, HbA1c, and duration on the expression of periodontal disease in T1DM subjects. Cross-tabulations and multivariable logistic regression analysis was performed on the periodontal data from T1DM subjects and non-diabetic subjects in order to determine the relationship between age, HbA1c and duration, and periodontitis. Diabetic subjects developed periodontitis at a younger age than non-diabetes subjects. This will represent a significant impact on life time dental service provision for subjects affected at a young age. The relationship between HbA1c and severe periodontitis is not a simple one. It is possible that unknown factors confound the relationship between glycaemic control and periodontitis. There was no relationship between duration of diabetes and periodontitis when age was controlled for. Chapter four presents the results of a small study investigating biomarkers of bone turnover in patients with and without T1DM and in patients with and without periodontitis. Patients with T1DM had higher levels of osteoprotegerin an osteoprotective molecule that normally leads to a reduced propensity for bone loss. T1DM patients were also shown to have reduced levels of biomarkers of bone formation (osteocalcin). It is possible that a reduced capacity for bone repair and regeneration may account for the increase levels of periodontitis seen in T1DM. Further prospective studies would be required to confirm this hypothesis. Chapter five investigated the level of caries and oral mucosal abnormalities in T1DM. There was little difference in caries indicators or in oral mucosal lesions between the groups. There was no difference in the bacterial microflora and in the level of resistance to antibiotics found in this cohort. T1DM patients, however, did have an increase in the symptoms of dry mouth, an increased density of candida colonisation and reduced salivary flow rates.Chapter six reports the data derived from the oral health questionnaire, including the Oral Health Impact Profile -14 (OHIP-14) and the Audit of Diabetes Dependent Quality of Life (ADDQOL©). Patients with T1DM, despite having increased levels of periodontal disease, reduced salivary flow rates and increased symptoms of xerostomia did not have higher OHIP scores by any measure. The reasons for this apparently negligible impact of oral disease or oral health related quality of life are discussed. The OHIP-14 was shown to have construct validity in this population although the correlations were relatively weak and the differences were small. It is possible that patients with T1DM do not consider the impact of their oral health to be a significant problem in light of their other on-going medical issues. This finding requires further in-depth investigation of the psychology behind this apparent reduced impact. This is the first study of its kind to examine the oral and dental health of non-smoking type 1 diabetic patients. The conclusions from the clinical data support the view that patients with T1DM should be targeted with oral and dental health advice. Encouragingly the prevalence of periodontitis was lower in well controlled diabetic subjects suggesting that the effect of T1DM on the oral cavity can be ameliorated by good glycaemic control even though logistic regression analysis did not show a linear relationship. It is important that health rofessionals work together in order to prevent and manage the oral complications of T1DM in the same way that there are preventive and screening programmes for other diabetic complications. The pathogenesis behind the increased prevalence and severity of periodontal disease in T1DM requires further study.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Caratterizzazione di Batteri Vibrio harveyi irradiati con luce UV e raggi X

Lo studio dei batteri sottoposti a stimolazioni dovute all'ambiente è di estremo interesse per impli-cazioni strutturali, meccanicistiche ed evolutive. Bat-teri luminescenti evoluti in determinati ambienti han-no sviluppato particolari risposte e il loro comporta-mento può fornire informazioni sulla funzione e sulla produzione dell‟enzima luciferina. Per esaminare l'in-terazione con radiazione UV, in condizioni controlla-te di laboratorio sono stati utilizzati ceppi batterici foto-luminescenti appartenenti alla specie Vibrio har-veyi campionati da una grotta costiera con elevato contenuto di radon che genera radiazioni ionizzanti. La sopravvivenza dei ceppi batterici è stata analizza-ta, alla luce e al buio, a seguito di una varietà di trat-tamenti genotossici tra cui esposizione alle radiazioni UV. I ceppi sono stati irradiati mediante una lampada germicida. I risultati hanno dimostrato che la maggior parte dei ceppi esibiscono un basso tasso di sopravvi-venza dopo l'esposizione ai raggi UV. Tutti i ceppi dopo esposizione a luce visibile e ai raggi UV hanno mostrato una forte capacità di fotoriattivazione. Que-sta capacità era inaspettata, poiché questi batteri sono stati prelevati da un ambiente buio in assenza raggi UV. Questo porta ad ipotizzare che la fotoriattivazio-ne in questi batteri potrebbe essere stata sviluppata dagli stessi per riparare le lesioni del DNA provocate anche da radiazioni diverse dall‟UV (ad esempio, raggi X) e che i batteri luminescenti potrebbero usare la luce da essi emessa per effettuare la fotoriattivazio-ne. L'elevata capacità di fotoriattivazione dei batteri è stata anche confermata dai risultati di deconvoluzio-ne. La deconvoluzione è stata applicata agli spettri di emissione che ha evidenziato la presenza di diversi picchi. La presenza del picco nel visibile è in grado di controllare l'enzima fotoliasi

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Application of XeCl308nm excimer laser radiation to mutagenesis of industrial microorganisms.

(UV) lamps are widely used in mutagenesis-selection protocols. Nevertheless, since the eighties, due to the development of excimer lasers, new frontiers in the study of UV applications have been opened. It has been established that the presence of an intact SOS response system is required for the mutagenic effect of UV254 nm. The exposure to UV254 nm radiation is not mutagenic for Escherichia coli mutants lacking the RecA protein, the regulator of the SOS response.We have recently demonstrated that at variance with the UV254 nm mutagenesis, the UV308 nm mutagenesis by XeCl308 nm excimer laser is RecA-independent. This suggests that the UV308 nm might be mutagenic also in microorganisms naturally lacking the SOS response. In this study, we have developed an innovative mutagenesis protocol based on a homemade XeCl308 nm excimer laser and have demonstrated its efficiency on mutagenesis of Nonomuraea American type culture collection 39727, an industrial strain producing an antibiotic, which is relatively refractory to UV254 nm radiation-induced mutagenesi

Association of a luminous Vibrio sp., taxonomically related to Vibrio harveyi, with Clytia linearis (Thornely, 1900) (Hydrozoa, Cnidaria)

A previously unknown association between a luminous Vibrio sp., taxonomically related to the species Vibrio harveyi and a common member of the shallow/mid water communities of the Mediterranean Sea, the hydrozoan Clytia linearis is described. All the specimens of C. linearis observed under blue light excitation showed both a natural luminescence appearing as a series of fine dots due to clytin, and a clear fluorescence on the external side of the perisarc around the colonies due to the presence of luminous bacteria. Luminous bacteria were isolated from the surface of C. linearis, their phenotypic characterization as isolates was performed by several morphological, biochemical, and cultural tests, completed with 16S rDNA sequence analysis. All the isolates were referred to a Vibrio sp. taxonomically related to V. harveyi. The association of the V. harveyi-related species with C. linearis, as already suggested for another hydroid, Aglaophenia octodonta, could be explained with the activity of these bacteria of feeding on the chitinous structures present in these hydroids. Moreover, the adhesion of the luminous bacterium (here referred to as Vibrio sp. CL1) on C. linearis may contribute to the survival of this Vibrio species in the marine environment providing a suitable growth habitat