The uncertainty in standardised sound power measurements: complying with ISO 17025

In the context of “testing laboratory” one of the most important aspect to deal with is the measurement result. Whenever decisions are based on measurement results, it is important to have some indication of the quality of the results. In every area concerning with noise measurement many standards are available but without an expression of uncertainty, it is impossible to judge whether two results are in compliance or not. ISO/IEC 17025 is an international standard related with the competence of calibration and testing laboratories. It contains the requirements that testing and calibration laboratories have to meet if they wish to demonstrate that they operate to a quality system, are technically competent and are able to generate technically valid results. ISO/IEC 17025 deals specifically with the requirements for the competence of laboratories performing testing and calibration and for the reporting of the results, which may or may not contain opinions and interpretations of the results. The standard requires appropriate methods of analysis to be used for estimating uncertainty of measurement. In this point of view, for a testing laboratory performing sound power measurement according to specific ISO standards and European Directives, the measurement of uncertainties is the most important factor to deal with. Sound power level measurement, according to ISO 3744:1994 , performed with a limited number of microphones distributed over a surface enveloping a source is affected by a certain systematic error and a related standard deviation. Making a comparison of measurement carried out with different microphone arrays is difficult because results are affected by systematic errors and standard deviation that are peculiarities of the number of microphones disposed on the surface, their spatial position and the complexity of the sound field. A statistical approach could give an overview of the difference between sound power level evaluated with different microphone arrays and an evaluation of errors that afflict this kind of measurement. Despite the classical approach that tend to follow the ISO GUM this thesis present a different point of view of the problem related to the comparison of result obtained from different microphone arrays.

Funzionalizzazione della mandibola dopo ricostruzione con lembo libero rivascolarizzato di fibula "single strut". Al di là del deficit di verticalità.

Obiettivi: Valutare la modalità  più efficace per la riabilitazione funzionale del limbo libero di fibula "single strut", dopo ampie resezioni per patologia neoplastica maligna del cavo orale. Metodi: Da una casistica di 62 ricostruzioni microvascolari con limbo libero di fibula, 11 casi sono stati selezionati per essere riabilitati mediante protesi dentale a supporto implantare. 6 casi sono stati trattati senza ulteriori procedure chirurgiche ad eccezione dell'implantologia (gruppo 1), affrontando il deficit di verticalità  della fibula attraverso la protesi dentaria, mentre i restanti casi sono stati trattati con la distrazione osteogenetica (DO) della fibula prima della riabilitazione protesica (gruppo 2). Il deficit di verticalità  fibula/mandibola è stato misurato. I criteri di valutazione utilizzati includono la misurazione clinica e radiografica del livello osseo e dei tessuti molli peri-implantari, ed il livello di soddisfazione del paziente attraverso un questionario appositamente redatto. Risultati: Tutte le riabilitazioni protesiche sono costituite da protesi dentali avvitate su impianti. L'età  media è di 52 anni, il rapporto uomini/donne è di 6/5. Il numero medio di impianti inseriti nelle fibule è di 5. Il periodo massimo di follow-up dopo il carico masticatorio è stato di 30 mesi per il gruppo 1 e di 38.5 mesi (17-81) di media per il gruppo 2. Non abbiamo riportato complicazioni chirurgiche. Nessun impianto è stato rimosso dai pazienti del gruppo 1, la perdita media di osso peri-implantare registrata è stata di 1,5 mm. Nel gruppo 2 sono stati riportati un caso di tipping linguale del vettore di distrazione durante la fase di consolidazione e un caso di frattura della corticale basale in assenza di formazione di nuovo osso. L'incremento medio di osso in verticalità è stato di 13,6 mm (12-15). 4 impianti su 32 (12.5%) sono andati persi dopo il periodo di follow-up. Il riassorbimento medio peri-implantare, è stato di 2,5 mm. Conclusioni: Le soluzioni più utilizzate per superare il deficit di verticalità  del limbo libero di fibula consistono nell'allestimento del lembo libero di cresta iliaca, nel posizionare la fibula in posizione ideale da un punto di vista protesico a discapito del profilo osseo basale, l'utilizzo del lembo di fibula nella versione descritta come "double barrel", nella distrazione osteogenetica della fibula. La nostra esperienza concerne il lembo libero di fibula che nella patologia neoplastica maligna utilizziamo nella versione "single strut", per mantenere disponibili tutte le potenzialità  di lunghezza del peduncolo vascolare, senza necessità  di innesti di vena. Entrambe le soluzioni, la protesi dentale ortopedica e la distrazione osteogenetica seguita da protesi, entrambe avvitate su impianti, costituiscono soluzioni soddisfacenti per la riabilitazione funzionale della fibula al di là  del suo deficit di verticalità . La prima soluzione ha preso spunto dall'osservazione dei buoni risultati della protesi dentale su impianti corti, avendo un paragonabile rapporto corona/radice, la DO applicata alla fibula, sebbene sia risultata una metodica con un numero di complicazioni più elevato ed un maggior livello di riassorbimento di osso peri-implantare, costituisce in ogni caso una valida opzione riabilitativa, specialmente in caso di notevole discrepanza mandibulo/fibulare. Decisiva è la scelta del percorso terapeutico dopo una accurata valutazione di ogni singolo caso. Vengono illustrati i criteri di selezione provenienti dalla nostra esperienza.

Vergleichende computergestützte funktionsmorphologische Analyse an Molaren cercopithecoider Primaten

Die Analyse funktioneller Zusammenhänge zwischen Ernährung und Zahnmorphologie ist ein wichtiger Aspekt primatologischer und paläontologischer Forschung. Als überdauernder Teil des Verdauungssystems geben Zähne die bestmöglichen Hinweise auf die Ernährungsstrategien (ausgestorbener) Arten und eine Fülle weiterer Informationen. Aufgrund dessen ist es für die wissenschaftliche Arbeit von größter Bedeutung, die Zähne so detailliert und exakt wie möglich in ihrer gesamten Struktur zu erfassen. Bisher wurden zumeist zweidimensionale Parameter verwendet, um die komplexe Kronenmorphologie von Primatenmolaren vergleichend zu untersuchen. Die vorliegende Arbeit hatte das Ziel, Zähne verschiedener Arten von Altweltaffen mittels computerbasierter Methoden dreidimensional zu erfassen und neue Parameter zu definieren, mit denen die Form dieser Zähne objektiv erfasst und funktionell interpretiert werden kann. Mit einem Oberflächen-Scanner wurden die Gebisse einer Stichprobe von insgesamt 48 Primaten von fünf verschiedenen Arten eingescannt und mit Bildverarbeitungsmethoden so bearbeitet, dass dreidimensionale digitale Modelle einzelner Backenzähne zur Analyse vorlagen. Es wurden dabei sowohl Arten ausgewählt, die eine für ihre Gattung typische Ernährungsweise besitzen - also Frugivorie bei den Cercopithecinen und Folivorie bei den Colobinen - als auch solche, die eine davon abweichende Alimentation bevorzugen. Alle Altweltaffen haben sehr ähnliche Molaren. Colobinen haben jedoch höhere und spitzere Zahnhöcker, dünneren Zahnschmelz und scheinen ihre Zähne weniger stark abzukauen als die Meerkatzen. Diese Beobachtungen konnten mit Hilfe der neuen Parameter quantifiziert werden. Aus der 3D-Oberfläche und der Grundfläche der Zähne wurde ein Index gebildet, der die Stärke des Oberflächenreliefs angibt. Dieser Index hat bei Colobinen deutlich höhere Werte als bei Cercopithecinen, auch bei Zähnen, die schon stark abgekaut sind. Die Steilheit der Höcker und ihre Ausrichtung wurden außerdem gemessen. Auch diese Winkelmessungen bestätigten das Bild. Je höher der Blätteranteil an der Ernährung ist, desto höher sind die Indexwerte und umso steiler sind die Höcker. Besonders wichtig war es, dies auch für abgekaute Zähne zu bestätigen, die bisher nicht in funktionelle Analysen miteinbezogen wurden. Die Ausrichtung der Höckerseiten gibt Hinweise auf die Kaubewegung, die zum effizienten Zerkleinern der Nahrung notwendig ist. Die Ausrichtung der Höcker der Colobinen deutet darauf hin, dass diese Primaten flache, gleitende Kaubewegungen machen, bei denen die hohen Höcker aneinander vorbei scheren. Dies ist sinnvoll zum Zerschneiden von faserreicher Nahrung wie Blättern. Cercopithecinen scheinen ihre Backenzähne eher wie Mörser und Stößel zu verwenden, um Früchte und Samen zu zerquetschen und zu zermahlen. Je nachdem, was neben der hauptsächlichen Nahrung noch gekaut wird, unterscheiden sich die Arten graduell. Anders als bisher vermutet wurde, konnte gezeigt werden, dass Colobinen trotz des dünnen Zahnschmelzes ihre Zähne weniger stark abkauen und weniger Dentin freigelegt wird. Dies gibt eindeutige Hinweise auf die Unterschiede in der mechanischen Belastung, die während des Kauvorgangs auf die Zähne wirkt, und lässt sich gut mit der Ernährung der Arten in Zusammenhang bringen. Anhand dieser modellhaften Beobachtungen können in Zukunft ausgestorbene Arten hinsichtlich ihrer Ernährungsweise mit 3D-Techniken untersucht werden.

Levobupivacain zur postoperativen Schmerztherapie bei Patienten mit Kniegelenksersatz - ein Vergleich mit Ropivacain

In der vorliegenden Arbeit wurde die postoperative analgetische Potenz von Levobupivacain mit derjenigen von Ropivacain nach Kniegelenkersatz an 60 Patienten (30 Patienten pro Gruppe) verglichen. Nach N. femoralis Katheteranlage und Einleitung einer Allgemeinanästhesie wurden die Patienten einer Kniegelenkersatzoperation unterzogen. Postoperativ erhielten die Patienten über eine PCA Pumpe für insgesamt 72 Stunden eine kontinuierliche Zufuhr des entsprechenden Lokalanästhetikums (5ml/h Levobupivacain 0,125% oder Ropivacain 0,2%), zusätzlich konnten über die PCA Pumpe Boli zu je 5ml des entsprechenden Lokalanästhetikums mit einer Sperrzeit von 30 Minuten angefordert werden. Der Lokalanästhetikaverbrauch sowie die Schmerzintensität (nach NRS) wurden bei Verlassen des Aufwachraumes sowie 24, 48 und 72 Stunden danach erfasst. Hinsichtlich der Anzahl der erhaltenen bzw. angeforderten Boli und des Gesamtvolumens in Millilitern zeigte sich kein statistisch signifikanter Unterschied. Auch die postoperative Schmerzintensität sowie der Opioidbedarf waren vergleichbar. Um diese vergleichbare Analgesie zu erreichen, benötigten Patienten der Ropivacain Gruppe, bezogen auf den Gesamtverbrauch in Milligramm, beinahe 70% mehr Lokalanästhetikum als Patienten der Levobupivacain Gruppe. Unter den Bedingungen dieser Studie ergab sich demnach für Ropivacain im Vergleich zu Levobupivacain eine deutlich geringere analgetische Potenz. Vor diesem Hintergrund relativieren sich generelle Aussagen hinsichtlich eines günstigeren Wirkprofils des Ropivacains.

Das chronische Postthorakotomie-Schmerzsyndrom: Eine vergleichende Untersuchung zweier Analgesieverfahren (PCEA und PCA+Ketamin)

Das chronische Postthorakotomie Schmerzsyndrom: Eine vergleichende Untersuchung zweier Analgesieverfahren (PCEA und PCA+Ketamin)rnrnFragestellung: Chronische Schmerzen im Narbenbereich nach Thorakotomien sind ein bekanntes und häufiges Problem. Die Prävalenz des chronischen Postthorakotomie Schmerzsyndroms sechs Monate postoperativ liegt zwischen 52% und 75%. Die Epiduralanästhesie gilt zurzeit als das beste Analgesieverfahren für Thorakotomiepatienten in Bezug auf das Auftreten akuter und chronischer Postthorakotomieschmerzen. In dieser Studie wurde untersucht, ob sich die Epiduralanästhesie (PCEA) und ein opioidbasiertes, systemisches Analgesieverfahren mit der zusätzlichen intravenösen Applikation von Ketamin, einem NMDA-Rezeptorantagonisten, (PCA+Ketamin) in der Prävalenz des chronischen Postthorakotomiesyndroms unterscheiden, oder ob beide Verfahren gleichwertig sind.rnrnMaterial u. Methoden: Es wurden die Datensätze von 173 Patienten, bei denen eine elektive Thorakotomie durchgeführt wurde, retrospektiv an Hand vorliegender Schmerzprotokolle erfasst. Ausgewertet wurden das durchgeführte Analgesieverfahren, die deskriptiven Daten der Patienten (Alter, Geschlecht, Hauptdiagnose, Zeitraum bis zur Nachbefragung), das postoperative Schmerzniveau der ersten beiden Tage, eventuelle Komplikationen und die Patientenzufriedenheit. Durch ein telefonisches Interview wurden die Patienten in einem Zeitraum von 6 bis 24 Monaten postoperativ zum aktuellen Schmerzniveau befragt.rnrnErgebnisse: Die beiden Analgesieverfahren PCEA (135 Patienten) und PCA+Ketamin (38 Patienten) unterscheiden sich signifikant in Bezug auf das Patientenalter, die Hauptdiagnose und das Schmerzniveau am 1. und 2. postoperativen Tag unter Belastung. Es konnte kein signifikanter Unterschied im Auftreten des chronischen Schmerzsyndroms nachgewiesen werden, allerdings gibt es einen deskriptiven Trend zu einer erhöhten Auftretenswahrscheinlichkeit des Postthorakotomiesyndroms in der Epiduralanästhesiegruppe (PCEA: 37,8% vs. PCA+Ketamin 23,7%).rnrnSchlussfolgerung: Die Ketamingabe zur PCA hat möglicherweise einen protektiven Effekt bezüglich der Prävalenz des Postthorakotomie Schmerzsyndroms. Auch wenn die Wirkungsweise des Ketamins auf den chronischen Postthorakotomieschmerz unklar ist, konnte in dieser Studie kein Unterschied in Bezug auf das Auftreten des chronischen Schmerzsyndroms zwischen den beiden Analgesiegruppen PCEA und PCA + Ketamin nachgewiesen werden. Unter Umständen könnte sogar ein Vorteil des PCA + Ketaminschemas gegenüber der Epiduralanästhesie bezüglich des Auftretens des Postthorakotomie Schmerzsyndroms bestehen. Dieser mögliche Vorteil sollte in weiteren Studien überprüft werden.rn

Investigation of different shellac grades and improvement of release from air suspension coated pellets

Shellac is the purified product of the natural polymer Lac. Shellac types, from different origins and with different ages, all purified by the solvent extraction process were compared in this study. Their physicochemical properties acid value, glass transition temperatures, color numbers and molecular sizes were determined. Metoprolol tartrate pellets were coated by air suspension coating with these different grades of shellac. Two coating levels 20% w/w and 25% w/w were applied and then subjected to in vitro dissolution testing. Enteric resistance was achieved for all tested brands for the two coating levels. At pH 6.8, 7.2 and 7.4, significant variations were obvious between the brands. rnMoreover the molecular size of shellac has a pronounced effect in that shellac types with larger molecular size show a higher and faster release than others, while the one with the smaller molecular size show the opposite effect on the release of metoprolol.rnIn this study commercially available ready for use aqueous shellac solutions (SSB AQUAGOLD), which are based on shellac SSB 57 (Dewaxed Orange Shellac, Bysakhi-Ber type refined in a solvent extraction process), with different manufacturing dates were used. rnTo improve the enteric coating properties of films from aqueous shellac solutions, different aqueous polymeric solutions of hydroxypropyl methylcellulose (HPMC), hydroxypropyl cellulose (HPC), carboyxmethyl cellulose (CMC), gum arabic and polysaccharides (Pullulan®) were used. These water soluble polymers will act as pore formers to enhance drug release from pellets coated with the combination of shellac and these polymers. The influence of these polymers on the gloss of the shellac films, mechanical properties of the films and drug release from metoprolol tartrate pellets were studied.rnThe potential of ethanol to alter the rate of drug release from shellac coated pellets was assessed by using a modified in vitro dose dumping in alcohol (DDA) method and the test concluded that shellac coated dosage forms can be co-administered with alcohol beverages containing ≤ 5% with no effect of alcohol on the shellac coat.rnPellets coated with shellac sodium salts, showed higher release rates than pellets coated with shellac as ammonium salt forms. rn

Proposta di sottotitolazione in italiano del film "Я шагаю по Москве" (1963)

Il tema del mio elaborato finale è la sottotitolazione del film “A passeggio per Mosca” di Georgij Danelija (1963), un noto regista russo. I suoi film più famosi sono “Мимино” (Mimino) e “Осенный марафон” (“Maratona d’autunno”). L’attore protagonista del film è Nikita Michalkov, famoso attore e regista, nonché personaggio controverso della vita culturale russa; il suo film più famoso è “Утомлённые солнцем” (“Sole ingannatore”). I personaggi più anziani furono interpretati da attori famosi quali Rolan Bykov, attore di teatro, e Vladimir Basov, regista e attore straordinariamente versatile. I ruoli principali, invece, furono affidati ad attori meno noti: Aleksej Loktev e Evgenij Steblov, che si dedicarono entrambi al teatro per gran parte della propria vita, e Galina Pol’skich, che divenne una grande attrice di film drammatici. Straordinari sono anche il lavoro dell’operatore cinematografico Vadim Jusov e quello del compositore Andrej Petrov. Il film suscitò diverse impressioni nel pubblico e nella critica e fu accolto positivamente da Chruščёv: presto sarebbe diventato un simbolo del “Disgelo”, un periodo in cui Chruščёv effettuò un’opera di destalinizzazione dell’URSS: il clima era quindi più disteso, sebbene vi fosse un malcontento diffuso a causa dell’economia fallimentare dello Stato. La canzone finale, che contribuì al successo del film, esprime perfettamente quest’atmosfera spensierata, che pervade anche Mosca, la vera protagonista del film. Della capitale vengono inquadrati i luoghi più importanti: tra questi il parco Gorkij, la metropolitana e il GUM. Tradurre i sottotitoli del film non è stato facile. In particolare, ho incontrato difficoltà nel tradurre alcune particelle russe che non hanno un equivalente in italiano e battute in cui erano presenti importanti riferimenti culturali. Il lavoro a cui mi sono dedicata con più impegno è stato la traduzione della canzone finale: desideravo che i sottotitoli italiani fossero in rima e conservassero il significato dei versi originari.

Teeth restored using fiber-reinforced posts: in vitro fracture tests and finite element analysis

In dentistry the restoration of decayed teeth is challenging and makes great demands on both the dentist and the materials. Hence, fiber-reinforced posts have been introduced. The effects of different variables on the ultimate load on teeth restored using fiber-reinforced posts is controversial, maybe because the results are mostly based on non-standardized in vitro tests and, therefore, give inhomogeneous results. This study combines the advantages of in vitro tests and finite element analysis (FEA) to clarify the effects of ferrule height, post length and cementation technique used for restoration. Sixty-four single rooted premolars were decoronated (ferrule height 1 or 2 mm), endodontically treated and restored using fiber posts (length 2 or 7 mm), composite fillings and metal crowns (resin bonded or cemented). After thermocycling and chewing simulation the samples were loaded until fracture, recording first damage events. Using UNIANOVA to analyze recorded fracture loads, ferrule height and cementation technique were found to be significant, i.e. increased ferrule height and resin bonding of the crown resulted in higher fracture loads. Post length had no significant effect. All conventionally cemented crowns with a 1-mm ferrule height failed during artificial ageing, in contrast to resin-bonded crowns (75% survival rate). FEA confirmed these results and provided information about stress and force distribution within the restoration. Based on the findings of in vitro tests and computations we concluded that crowns, especially those with a small ferrule height, should be resin bonded. Finally, centrally positioned fiber-reinforced posts did not contribute to load transfer as long as the bond between the tooth and composite core was intact.

Comparing expectations and experiences of care for sexually transmitted infections in general practice: a qualitative study

Background A key aim of England's National Strategy for Sexual Health is to extend high-quality sexual health services in primary care. Objectives To explore the expectations and experiences of men and women who initially presented at their general practice with a suspected sexually transmitted infection in order to identify areas where change could improve service delivery. Methods Semi-structured interviews were carried out in six general practices and two genitourinary medicine (GUM) clinics in Brent primary care trust (London) and Bristol (southwest England). Patients within general practice, and GUM patients who had initially attended general practice were eligible to participate. Interview transcripts were analysed using thematic analysis. Results 49 patients (29 women, 20 men) were interviewed. Patients approaching their GP practice typically expected written referral or in-house care, but this expectation was often not met. Absence of formal referral, lack of information and perceived avoidance of sexual health matters by practitioners were commonly cited as reasons for disappointment. However, a dedicated service within general practice met expectations well. Conclusion Purchasers and providers of all general practice services should ensure that any patient consulting in primary care with a suspected sexually transmitted infection can either receive appropriate care there, or a formal and supported referral to a specialised GUM clinic or primary care service.

Testing for sexually transmitted infections in general practice: cross-sectional study

Background Primary care is an important provider of sexual health care in England. We sought to explore the extent of testing for chlamydia and HIV in general practice and its relation to associated measures of sexual health in two contrasting geographical settings. Methods We analysed chlamydia and HIV testing data from 64 general practices and one genitourinary medicine (GUM) clinic in Brent (from mid-2003 to mid-2006) and 143 general practices and two GUM clinics in Avon (2004). We examined associations between practice testing status, practice characteristics and hypothesised markers of population need (area level teenage conception rates and Index of Multiple Deprivation, IMD scores). Results No HIV or chlamydia testing was done in 19% (12/64) of general practices in Brent, compared to 2.1% (3/143) in Avon. In Brent, the mean age of general practitioners (GPs) in Brent practices that tested for chlamydia or HIV was lower than in those that had not conducted testing. Practices where no HIV testing was done had slightly higher local teenage conception rates (median 23.5 vs. 17.4/1000 women aged 15-44, p = 0.07) and served more deprived areas (median IMD score 27.1 vs. 21.8, p = 0.05). Mean yearly chlamydia and HIV testing rates, in practices that did test were 33.2 and 0.6 (per 1000 patients aged 15-44 years) in Brent, and 34.1 and 10.3 in Avon, respectively. In Brent practices only 20% of chlamydia tests were conducted in patients aged under 25 years, compared with 39% in Avon. Conclusions There are substantial geographical differences in the intensity of chlamydia and HIV testing in general practice. Interventions to facilitate sexually transmitted infection and HIV testing in general practice are needed to improve access to effective sexual health care. The use of routinely-collected laboratory, practice-level and demographic data for monitoring sexual health service provision and informing service planning should be more widely evaluated.

Variation in partner notification outcomes for chlamydia in UK genitourinary medicine clinics: multilevel study

Objectives To compare different ways of measuring partner notification (PN) outcomes with published audit standards, examine variability between clinics and examine factors contributing to variation in PN outcomes in genitourinary medicine (GUM) clinics in the UK. Methods Reanalysis of the 2007 BASHH national chlamydia audit. The primary outcome was the number of partners per index case tested for chlamydia, as verified by a healthcare worker or, if missing, reported by the patient. Control charts were used to examine variation between clinics considering missing values as zero or excluding missing values. Hierarchical logistic regression was used to investigate factors contributing to variation in outcomes. Results Data from 4616 individuals in 169 genitourinary medicine clinics were analysed. There was no information about the primary outcome in 41% of records. The mean number of partners tested for chlamydia ranged from 0 to 1.5 per index case per clinic. The median across all clinics was 0.47 when missing values were assumed to be zero and 0.92 per index case when missing values were excluded. Men who have sex with men were less likely than heterosexual men and patients with symptoms (4-week look-back period) were less likely than asymptomatic patients (6-month look-back) to report having one or more partners tested for chlamydia. There was no association between the primary outcome and the type of the health professional giving the PN advice. Conclusions The completeness of PN outcomes recorded in clinical notes needs to improve. Further research is needed to identify auditable measures that are associated with successful PN that prevents repeated chlamydia in index cases.

Parenteral nutrition does not improve postoperative recovery from radical cystectomy: results of a prospective randomised trial

After radical cystectomy, patients are in a catabolic state because of postoperative stress response, extensive wound healing, and ileus.

Equine botulism and acute pasture myodystrophy: new soil-borne emerging diseases in Switzerland?

In Switzerland, the incidence of equine botulism and acute pasture myodystrophy have remarkably increased in the last five years. Equine fodder-borne botulism in Europe is most likely caused by Clostridium botulinum types C and D that produce the toxins BoNT/C and BoNT/D. Horses showing signs suggestive of botulism (muscle weakness and tremors, reduced tongue tone, slow chewing, salivation and difficulties swallowing, drooping eyelids, mydriasis), especially patients that have fed on suspect fodder (mostly haylage), must be treated with anti-serum as soon as possible.They also need intensive care, which is often difficult to provide and always expensive in the face of a guarded to poor prognosis. Therefore, prevention (high standards of forage quality and vaccination) is all the more important. Pasture myodystrophy is an acute disease with signs of rhabdomyolysis and lethality rate over 90%. It affects grazing horses under frosty, windy and rainy conditions. Preliminary results indicate that Clostridium sordellii and Clostridium bifermentans producing lethal toxin may play a role in pasture myodystrophy. Our efforts concentrate on developing a new subunit vaccine for equine botulism and understanding the ethiology and pathogenesis of pasture myodystrophy with the goal of improving prevention against these highly fatal diseases that present a significant risk to our horse population.

Extrinsic causes of erosion. Oral hygiene products and acidic medicines

Acidic or EDTA-containing oral hygiene products and acidic medicines have the potential to soften dental hard tissues. The low pH of oral care products increases the chemical stability of some fluoride compounds, favors the incorporation of fluoride ions in the lattice of hydroxyapatite and the precipitation of calcium fluoride on the tooth surface. This layer has some protective effect against an erosive attack. However, when the pH is too low or when no fluoride is present these protecting effects are replaced by direct softening of the tooth surface. Xerostomia or oral dryness can occur as a consequence of medication such as tranquilizers, anti-histamines, anti-emetics and anti-parkinsonian medicaments or of salivary gland dysfunction e.g. due to radiotherapy of the oral cavity and the head and neck region. Above all, these patients should be aware of the potential demineralization effects of oral hygiene products with low pH and high titratable acids. Acetyl salicylic acid taken regularly in the form of multiple chewable tablets or in the form of headache powder as well chewing hydrochloric acids tablets for treatment of stomach disorders can cause erosion. There is most probably no direct association between asthmatic drugs and erosion on the population level. Consumers, patients and health professionals should be aware of the potential of tooth damage not only by oral hygiene products and salivary substitutes but also by chewable and effervescent tablets. Additionally, it can be assumed that patients suffering from xerostomia should be aware of the potential effects of oral hygiene products with low pH and high titratable acids.

What can be gained from comprehensive disaggregate surveillance? The Avon Surveillance System for Sexually Transmitted Infections

OBJECTIVE: To describe a new disaggregate surveillance system covering key diagnosed sexually transmitted infections in a UK locality. METHODS: The Avon System for Surveillance of Sexually Transmitted Infections (ASSIST) collects computerised person- and episode-based information about laboratory-diagnosed sexually transmitted infections from genitourinary medicine (GUM) clinics, the Avon Brook Clinic, and the Health Protection Agency and trust laboratories in primary care trusts in Avon. The features of the system are illustrated here, by describing chlamydia-testing patterns according to the source of test, age and sex, and by mapping the distribution of chlamydia across Bristol, UK. RESULTS: Between 2000 and 2004, there were 821,685 records of tests for sexually transmitted infections, with 23,542 positive results. The proportion of tests and positive results for chlamydia and gonorrhoea sent from general practice increased over time. Most chlamydia tests in both GUM and non-specialist settings were performed on women aged >25 years, but positivity rates were highest in women aged <25 years. The positivity rate remained stable between 2000 and 2004. Including data from all diagnostic settings, chlamydia rates were about twice as high as those estimated only from genitourinary clinic cases. CONCLUSIONS: The ASSIST model could be a promising new tool for planning and measuring sexual health services in England if it can become sustainable and provide more timely data using fewer resources. Collecting denominator data and including infections diagnosed in primary care are essential for meaningful surveillance.