Surgical procedures at the maxillary sinuses and upper cheek teeth controlled by the c-arch technique

Deckblatt-Impressum persönlicher Dank Inhaltsverzeichnis Abkürzungsverzeichnis Einleitung Literaturübersicht Eigene Untersuchungen Diskussion Zusammenfassung Summary Literaturverzeichnis Anhang Danksagung Lebenslauf SelbständigkeitserklärungBackenzahnerkrankungen beim Pferd stellen eine häufig auftretende Problematik in der Veterinärmedizin dar. Die auftretenden Veränderungen an den Molaren und Prämolaren sind in der Regel irreversibel. Oft sind Backenzähne so massiv geschädigt, dass eine Extraktion unumgänglich ist. Bei Infektionen kommt es häufig zum Übertreten der bestehenden Entzündung auf den Alveolarknochen. Dieser wird zerstört und ein Übergriff auf die Oberkieferhöhle wird möglich. Muss ein Backenzahn schließlich entfernt werden, sind verschiedene Techniken bekannt: die orale Extraktion, die laterale Bukkotomie sowie die Repulsions- methode. Jede dieser Techniken besitzt ihre Vor- und Nachteile und ist nicht in jedem Fall anwendbar. Für die Wahl der Operationstechnik ist eine genaue Diagnostik notwendig. Während die laterale Bukkotomie als jüngste Methode hauptsächlich für die Prämolaren geeignet ist, findet die orale Extraktion, als älteste und einfachste Methode, sowohl bei alten Pferden mit kurzen Zahnwurzeln und/oder stark geschädigten Backenzähnen, als auch bei jungen Pferden zur Entfernung persistierender Milchzähne Anwendung. Die langen, fest in der Alveole verankerten Zahnwurzeln in Kombination mit dem geringen Öffnungswinkel des Pferdemaules machen eine orale Extraktion eines Backenzahnes oft unmöglich. Die Repulsionsmethode durch die eröffnete Oberkieferhöhle ist ebenfalls eine sehr alte Methode. Die Eröffnung der Oberkieferhöhle kann entweder mittels Trepanation oder Knochenflap-Technik geschehen. Die Schwierigkeit dieser Technik liegt in der Lagebestimmung der Zahnwurzel des zu extrahierenden Zahnes. Die Lage der Zahnwurzel muss von außen auf einer gedachten Linie nach (Günther, et al., 1967) bestimmt werden. Denn oberhalb des bestimmten Lagepunktes der Zahnwurzel wird die Kieferhöhle eröffnet und der Stempel blind aufgesetzt. Diese nur ungenaue Bestimmung kann zu fatalen Folgen für den Patienten führen, da eine Schädigung oder gar Entfernung des benachbarten Zahnes möglich ist. Ebenfalls kann es, durch massive Krafteinwirkung auf den Zahnstempel, zur Zerstörung der Alveole oder des Gaumendaches kommen. Anders ist es bei einer Zahnextraktion unter Anwendung der intraoperativen Durchleuchtung mit Hilfe der C-Bogen-Technik. Hier besteht für den Operateur während des gesamten chirurgischen Eingriffs die Möglichkeit alle seine operativen Handlungen zu kontrollieren. So ist unter anderem die exakte Identifikation des zu entfernenden Zahnes möglich, sowie eine ständige Kontrolle der Platzierung des Instrumentariums. Um die Zahnwurzeln der Backenzähne bei der intraoperativen Durchleuchtung exakt beurteilen zu können, muss eine möglichst überlagerungsfreie Darstellung der einzelnen Zahnreihen gelingen. Dazu muss der C-Bogen in einem Winkel von 115° für die rechte und 245° für die linke Backenzahnreihe an den Pferdekopf heran gefahren werden. Zusätzlich ermöglicht die intraoprative Durchleuchtungs- kontrolle eine Überprüfung der Alveole direkt im Anschluss an die Zahnextraktion auf vollständige Entfernung des Zahnes. Befinden sich noch Fragmente im Zahnfach, können diese sofort entfernt werden, ohne, dass eine erneute Vollnarkose notwendig wird. Verbleibende Zahnreste behindern den Granulationsvorgang im Zahnfach massiv. Durch den Abstoßungsprozess entstehen Fistelkanäle, welche eine erneute chirurgische Entfernung in Narkose notwendig machen. Wie die Auswertung der stationären Patientenkartei bestätigt, resultiert aus dieser verbesserten Operationstechnik ein Vermeiden der obengenannten intraoperativen Komplikationen und es wird eine bessere Genesung für den Patienten gewährleistet. Um die Zahnwurzeln der Backenzähne exakt beurteilen zu können, muss eine möglichst überlagerungsfreie Darstellung der einzelnen Zahnreihen gelingen, dazu muss der C-Bogen in einem Winkel von 115° für die rechte und 245° für die linke Backenzahnreihe an den Pferdekopf heran gefahren werden. Durch eine Serie von Röntgenaufnahmen, die während einer Zahnextraktion gemacht wurde, soll die gute Darstellbarkeit mit Hilfe der C -Bogen-Technik demonstriert werden. Ziel dieser Dissertation ist es, das operative Handling und die Genauigkeit der C-Bogen-Navigation bei chirurgischen Eingriffen an den Oberkieferhöhlen und backenzähnen beim Pferd zu demonstrieren. Die Einsatzmöglichkeiten dieser Methode im Bereich der Oberkieferhöhlen und backenzähne soll erläutert werden. Außerdem wird deutlich, dass die häufig auftretenden intraoperativen Komplikationen bei der Durchführung des retrograden Ausstempelns vermieden und diese historische Methode somit verbessert werden kann. Dies wurde durch Eigenversuche an Schlachtpferdeköpfen erprobt und anhand einer Auswertung der stationären Patientenkartei bewiesen.Dental diseases present a frequently appearing problem in equine medicine. The appearing changes at the molar and premolar teeth are normally irreversible. Often the molars are so massively damaged, that an extraction is unavoidable. Infections lead frequently to the encroachment of the existing infection to the alveolar bone, which will be destroyed and an encroachment of the inflammation on the maxillary sinus becomes possible. Must a molar finally be removed, different techniques are known: the oral extraction, the lateral buccotomy as well as the Repulsion. Each of these techniques owns their before- and disadvantages and therefore not each technology is applicable in each case. For the choice of the surgical technique an exact diagnostic is necessary. While the lateral buccotomy is suitable as latest method, mainly for the premolar teeth, oral extraction, as oldest and simplest method, applies only at old horses with short roots and/or greatly damaged teeth, as well as at the removal of persistent temporary teeth of young horses. Long roots firmly with the alveolus connected in combination with the limited oral access of the equine mouth makes an oral extraction of premolar and molar teeth often impossible. The repulsion through the opened maxillary sinus is likewise a very old method. The opening of the maxillary sinus can happen either by means of trepanation or bone- flap. The difficulty of this technology is situated in the determination the root of the tooth, which should be extracted, because the position of the root must be seted from external face of the equine head on a remembered line after Guenther, et al. (1967). Because above the certain position of the root the maxillary sinus is opened and the punch is put on it blindly. This only inaccurate determination can lead to fatal consequences for the patient, because a damage or maybe a removal of the adjacent tooth is possible. Likewise, through the excessive force which is influencing on the dental punch, the alveolus or the palatine bone might be destructed. The case is different by tooth extraction with application of the intraoperative illumination with the C-arch. This offers the surgeon during the whole surgical procedure the possibility to controll all his operative acts. So among others an exact identification of the tooth which should be removed is possible, as well as the permanent control of the placement of the instrumentarium. By the intraoperative fluoroscopy controll the alveolus can be checked immediately following the tooth extraction on complete removal. If still fragments are found in the tooth socket, these could be removed immediately, without, a renewed general anesthetic. Retained tooth fragments disturb the granulation in the dental socket massively. The remaining dental rests appear fistulation, which make a renewed surgical removal in anaesthesia necessary. The evaluation of the stationary patients confirm, that an improved surgical technique results in avoiding of the above- mentioned intraoperative complications, thus guaranteed a better recovery for the patient. To be able to judge the roots of the molars exactly, the superimpositon of the contralateral dental arcades must be prevented. To reach this the C-arch must be driven in an angle of 115 degree for the right and 245 degree for the left dental arcade at the equine head. A serie of x-rays was made during a tooth extraction, to demonstrate the very good representation which would reached with the help of the C-arch-technology. The aim of this theses is, to demonstrate the operative handling and precision of the C-arch navigation by surgery at the maxillary sinuses and premolar and molar teeth at the horse and to illustrate the possibilities of using from this method in the area of the equine upper jaw. Moreover becomes clear, that the frequently appearing of intraoprative complications, which appear by the accomplishment of retrograde repulsion could be avoided and thus this process can be improved. This was tested with heads of slaughterhorses and poved with an evaluation of the stationary patients

Methicillin-resistant Staphylococcus aureus ST398 in Humans and Animals, Central Europe

Isolates found in persons and animals in Germany and Austria show a genetic relationship

Genomic insights into the emergence and spread of international clones of healthcare-, community- and livestock-associated meticillin- resistant Staphylococcus aureus: Blurring of the traditional definitions

The evolution of meticillin-resistant Staphylococcus aureus (MRSA) from meticillin-susceptible S. aureus has been a result of the accumulation of genetic elements under selection pressure from antibiotics. The traditional classification of MRSA into healthcare-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) is no longer relevant as there is significant overlap of identical clones between these groups, with an increasing recognition of human infection caused by livestock-associated MRSA (LA-MRSA). Genomic studies have enabled us to model the epidemiology of MRSA along these lines. In this review, we discuss the clinical relevance of genomic studies, particularly whole-genome sequencing, in the investigation of outbreaks. We also discuss the blurring of each of the three epidemiological groups (HA-MRSA, CA-MRSA and LA-MRSA), demonstrating the limited relevance of this classification

Multiparametric determination of genes and their point mutations for identification of beta-lactamases

More than half of all currently used antibiotics belong to the beta-lactam group, but their clinical effectiveness is severely limited by antibiotic resistance of microorganisms that are the causative agents of infectious diseases. Several mechanisms for the resistance of Enterobacteriaceae have been established, but the main one is the enzymatic hydrolysis of the antibiotic by specific enzymes called beta-lactamases. Beta-lactamases represent a large group of genetically and functionally different enzymes of which extended-spectrum beta-lactamases (ESBLs) pose the greatest threat. Due to the plasmid localization of the encoded genes, the distribution of these enzymes among the pathogens increases every year. Among ESBLs the most widespread and clinically relevant are class A ESBLs of TEM, SHV, and CTX-M types. TEM and SHV type ESBLs are derived from penicillinases TEM-1, TEM-2, and SHV-1 and are characterized by several single amino acid substitutions. The extended spectrum of substrate specificity for CTX-M beta-lactamases is also associated with the emergence of single mutations in the coding genes. The present review describes various molecular-biological methods used to identify determinants of antibiotic resistance. Particular attention is given to the method of hybridization analysis on microarrays, which allows simultaneous multiparametric determination of many genes and point mutations in them. A separate chapter deals with the use of hybridization analysis on microarrays for genotyping of the major clinically significant ESBLs. Specificity of mutation detection by means of hybridization analysis with different detection techniques is compared

Complete Genome Sequences of Two Nosocomiicoccus ampullae Strains and a Growth-Adapted Mutant

Here, we present the circular and complete genome sequences of the Nosocomiicoccus ampullae isolate 19-00310 and type strain DSM 19163. To our knowledge, these represent the first complete, circular chromosomes in the entire genus. Sequencing of a growth-adapted mutant suggests iron availability as a factor for growth improvement.Peer Reviewe

Molecular Methods for Detection of Antimicrobial Resistance

ABSTRACT The increase in bacteria harboring antimicrobial resistance (AMR) is a global problem because there is a paucity of antibiotics available to treat multidrug-resistant bacterial infections in humans and animals. Detection of AMR present in bacteria that may pose a threat to veterinary and public health is routinely performed using standardized phenotypic methods. Molecular methods are often used in addition to phenotypic methods but are set to replace them in many laboratories due to the greater speed and accuracy they provide in detecting the underlying genetic mechanism(s) for AMR. In this article we describe some of the common molecular methods currently used for detection of AMR genes. These include PCR, DNA microarray, whole-genome sequencing and metagenomics, and matrix-assisted laser desorption ionization–time of flight mass spectrometry. The strengths and weaknesses of these methods are discussed, especially in the context of implementing them for routine surveillance activities on a global scale for mitigating the risk posed by AMR worldwide. Based on current popularity and ease of use, PCR and single-isolate whole-genome sequencing seem irreplaceable.</jats:p

New Investigations in the Environment, History and Archaeology of the Iraqi Hilly Flanks: Shahrizor Survey Project 2009-2011

Recent palaeoenvironmental, historical, and archaeological investigations, primarily consisting of site reconnaissance, in the Shahrizor region within the province of Sulaymaniyah in Iraqi Kurdistan are bringing to light new information on the region’s social and socio-ecological development. This paper summarises two seasons of work by researchers from German, British, Dutch, and Iraqi-Kurdish institutions working in the survey region. Palaeoenvironmental data have determined that during the Pleistocene many terraces developed which came to be occupied by a number of the larger tell sites in the Holocene. In the sedimentary record, climatic and anthropogenic patterns are noticeable, and alluviation has affected the recovery of archaeological remains through site burial in places. Historical data show the Shahrizor shifting between periods of independence, either occupied by one regional state or several smaller entities, and periods that saw the plain’s incorporation within large empires, often in a border position. New archaeological investigations have provided insight into the importance of the region as a transit centre between Western Iran and northern and southern Mesopotamia, with clear material culture links recovered. Variations between periods’ settlement patterns and occupations are also beginning to emerge

Diversity of Staphylococcus aureus Isolates in European Wildlife

Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle- associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock- associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation

Genome-Wide Association Studies for the Detection of Genetic Variants Associated With Daptomycin and Ceftaroline Resistance in Staphylococcus aureus

Background: As next generation sequencing (NGS) technologies have experienced a rapid development over the last decade, the investigation of the bacterial genetic architecture reveals a high potential to dissect causal loci of antibiotic resistance phenotypes. Although genome-wide association studies (GWAS) have been successfully applied for investigating the basis of resistance traits, complex resistance phenotypes have been omitted so far. For S. aureus this especially refers to antibiotics of last resort like daptomycin and ceftaroline. Therefore, we aimed to perform GWAS for the identification of genetic variants associated with DAP and CPT resistance in clinical S. aureus isolates. Materials/methods: To conduct microbial GWAS, we selected cases and controls according to their clonal background, date of isolation, and geographical origin. Association testing was performed with PLINK and SEER analysis. By using in silico analysis, we also searched for rare genetic variants in candidate loci that have previously been described to be involved in the development of corresponding resistance phenotypes. Results: GWAS revealed MprF P314L and L826F to be significantly associated with DAP resistance. These mutations were found to be homogenously distributed among clonal lineages suggesting convergent evolution. Additionally, rare and yet undescribed single nucleotide polymorphisms could be identified within mprF and putative candidate genes. Finally, we could show that each DAP resistant isolate exhibited at least one amino acid substitution within the open reading frame of mprF. Due to the presence of strong population stratification, no genetic variants could be associated with CPT resistance. However, the investigation of the staphylococcal cassette chromosome mec (SCCmec) revealed various mecA SNPs to be putatively linked with CPT resistance. Additionally, some CPT resistant isolates revealed no mecA mutations, supporting the hypothesis that further and still unknown resistance determinants are crucial for the development of CPT resistance in S. aureus. Conclusion: We hereby confirmed the potential of GWAS to identify genetic variants that are associated with antibiotic resistance traits in S. aureus. However, precautions need to be taken to prevent the detection of spurious associations. In addition, the implementation of different approaches is still essential to detect multiple forms of variations and mutations that occur with a low frequency.Peer Reviewe

First Report of a Methicillin-Resistant, High-Level Mupirocin-Resistant Staphylococcus argenteus

We describe the identification of a methicillin-resistant, high-level mupirocin-resistant Staphylococcus argenteus. The isolate (1801221) was characterized as t6675-ST2250-SCCmecIVc, and whole-genome sequencing revealed that the isolate possessed two plasmids. One plasmid (34,870 bp), designated p1_1801221 with rep23, harboured the mupirocin resistance (mupA) gene. The second plasmid (20,644 bp), assigned as p2_1801221 with rep5a and rep16, carried the resistance determinants for penicillin (blaZ) and cadmium (cadD). Phylogenetic analysis revealed that the isolate clustered with the European ST2250 lineage. The overall high similarity of both plasmids in S. argenteus with published DNA sequences of Staphylococcus aureus plasmids strongly suggests an interspecies transfer. The pathogenic potential, community and nosocomial spread, and acquisition of antibiotic resistance gene determinants, including the mupA gene by S. argenteus, highlight its clinical significance and the need for its correct identificationPeer Reviewe