Streptococcus pneumoniae antibiotikum rezisztenciájának geno- és fenotípusos felmérése = Geno-and phenotypic characterisation of antibiotic resistance of Streptococcus pneumoniae

A legfontosabb projekt az invazív pneumococcusok epidemiológiai felmérése volt. Ez az anyag majdnem teljesen készen áll, utolsó simítások után már csak a cikk megírása van hátra. Egy másik komoly projektbe is belekezdtünk, az óvodások orrában hordozott pneumococcusok epidemiológiai felmérésébe, mivel ilyen jellegű felmérés Magyarországon még nem történt, viszont a hordozók jelentik a fertőzés fő forrását. Mindkét téma szorosan összefügg a Prevenar védőoltás hazai bevezetésével (2005) és 2 év alatti gyerekek számára ingyenessé válásával (2008 október). A törzsek szerotipizálását egy általunk továbbfejlesztett protokol alapján végeztük, amelyben ötvözzük a hagyományos savós módszert egy PCR alapúval. A törzseknek kb. 3/4-ét sikerült így szerotipizálnunk, ami nagyon jó arány. A kapott eredmények szerint a Prevenar hazánkban a pneumococcus fertőzések kb. 53%-át védené csak ki, de ez is sokkal jobb, mintha egyáltalán nem lenne oltás. Még jobb lesz a két jövőbeni konjugált vakcina. A fluoroquinolon rezisztencia vizsgálatát során megállapítottuk, hogy egyelőre ugyan a rezisztencia kismértékű, de több jel is arra mutat, hogy ennek kiugrása várható. Érdemes lenne visszafogni a fluoroquinolonok légúti fertőzésekben való széleskörű használatát. Ezenkívül néhány metodikai fejlesztést is végeztünk, mint pl. a PFGE optimalizációja, a PFGE és MLST módszerek összehasonlítása, vagy az aktív szén tartalmú táptalajok használata, ami mind a labormunkát könnyíti meg. | The most important project was the epidemiological survey of invasive pneumococci. This is nearly completed now, only the puplication is left. We have started another big project: the epidemiological survey of pneumococci isolated from the nose of healthy children attending day-care centres. Such study has not been done in Hungary before, despite that carriers are the main source of an infection. Both projects are strictly linked with the introduction of Prevenar vaccine, and its free availability for children <2 years since October 2008. Serotyping of the strains was performed with the combination of the conventional method with antisera and PCR, developed by us. We managed to determine the serotype of about 78% of all isolates, which is a very good ratio. Our results show that the coverage of Prevenar is only about 53% for invasive infections, which is not too high, but still much better than having no vaccination at all. The two new conjugate vaccines will have better coverage rates. We have also thoroughly examined the fluoroquinolon resistance, and concluded that although resistance is still at low levels, but several signs point towards a possible sharp increase in the future. It would be advisable to suppress the wide usage of fluoroquinolones in respiratory tract infections. A few methodological studies, such as optimisation of PFGE, comparison of PFGE and MLST, or mixing charcoal into pneumococcal media can help in the everyday laboratory work

A konjugált pneumococcus vakcina hatásainak felmérése, invazív és multirezisztens Streptococcus pneumoniae izolátumok vizsgálata = Determining the effects of the conjugate pneumococcal vaccine, examination of invasive and multi-resistant Streptococcus pneumoniae isolates

2009 áprilisi ajánlott oltásként való bevezetése óta ugrásszerűen megnőtt a pneumococcus konjugált vakcina (Prevenar-7 és -13) átoltottsági aránya. A pályázat keretében lényegében a vakcinálás hatásait vizsgáltuk két különböző csoportban: súlyos fertőzésekből izolált (n=144), illetve egészséges óvodások orrában hordozott (n=324) törzsek esetében. Utóbbihoz eddig 856 kisgyereket szűrtünk le. Az összes izolátum (n=468) közül 441 esetben (=94,2%) sikerült a szerotípust meghatározni, ami kiemelkedően jó aránynak számít nemzetközi mértékkel mérve is. Ehhez hozzájárult egy jól működő szerotipizálási módszer kidolgozása, amely a hagyományos antiszérumos meghatározást ötvözi a PCR alapú detektálással. A hordozott törzsek esetében rendkívül izgalmas nyomon követni a vakcinálás hatására átrendeződő szerotípus eloszlást: a régi, világszerte gyakori típusokat (14, 19F, 23F, 18C, 6A/B) folyamatosan váltják fel az eddig egészen ritkának számítók (11A, 15B, 3), és különleges típusok is (16F, 22, 10A) előkerültek. Az új szerotípusok valószínűleg új vakcina kidolgozását teszik szükségessé. Ezt a kísérleti vonalat mindenképpen szeretnénk folytatni. Szerencsére mind a klinikai, mind a hordozott törzsek antibiotikum érzékenysége magas, az új, „emerging” klónoké még kedvezőbb. Vizsgáltuk a pneumococcusok biofilm képző képességét és ezzel összefüggően a pílusok jelenlétét is, amelyek eredményeink szerint – a vakcina hatáson túl - hozzájárulhatnak az újabb klónok sikeres terjedéséhez. | Vaccination of children with the conjugate pneumococcal vaccine (Prevenar-7 and -13) has drastically increased since its introduction as a recommended vaccine in April 2009. In the frame of the current grant, we have surveyed the effects of the vaccination in two different groups: isolates causing severe infections (n=144), and strains carried by healthy children (n=324). For this latter, we have screened 856 children so far. Out of all isolates (n=468), we managed to determine the serotype in 441 cases (=94,2%), which is a very good rate even by international standards. This was largely due to the development of a new serotyping protocol, combining the conventional antiserum method with PCR detection. It was extremely exciting to follow the rearrangement in serotype distribution due to the vaccine effect: the old, world-wide spread types (14, 19F, 23F, 18C, 6A/B) vanished or decreased and new types (11A, 15B, 3), even very rare ones (16F, 22 or 10A) emerged. The emergence of new types will sooner or later recall the need for a new vaccine. We definitely would like to continue the investigation of the carried pneumococci. Luckily both the clinical and the carried isolates showed high antibiotic sensitivity, especially the newly emerging types have low MICs. We have also investigated the biofilm forming ability of pneumococci and the presence of piluses, both of which can contribute – additionally to the vaccine effect – to the spread of the selected new clones

Predicting Optimal Lengths of Random Knots

In thermally fluctuating long linear polymeric chain in solution, the ends come from time to time into a direct contact or a close vicinity of each other. At such an instance, the chain can be regarded as a closed one and thus will form a knot or rather a virtual knot. Several earlier studies of random knotting demonstrated that simpler knots show their highest occurrence for shorter random walks than more complex knots. However up to now there were no rules that could be used to predict the optimal length of a random walk, i.e. the length for which a given knot reaches its highest occurrence. Using numerical simulations, we show here that a power law accurately describes the relation between the optimal lengths of random walks leading to the formation of different knots and the previously characterized lengths of ideal knots of the corresponding type

Circumscription: Proust\u27s The Captive and the Problem of Other Minds

Central to Proust\u27s Remembrance as a whole and to The Captive in particular is Marcel\u27s attempt to discover what other people think and feel. But, as reading the work in the light of modern analytic philosophy shows, his efforts are thwarted by the deceptions of others and by his own irreconcilable views. The other is radically inaccessible, yet the object of our search; the self is a stable entity, yet multiple, changing, and a fiction constituted by language; language is communication, yet the source of error. These are the problems which confront philosophy and literature when they try to come to terms with the otherness of others

Automated wound segmentation and classification of seven common injuries in forensic medicine

In forensic medical investigations, physical injuries are documented with photographs accompanied by written reports. Automatic segmentation and classification of wounds on these photographs could provide forensic pathologists with a tool to improve the assessment of injuries and accelerate the reporting process. In this pilot study, we trained and compared several preexisting deep learning architectures for image segmentation and wound classification on forensically relevant photographs in our database. The best scores were a mean pixel accuracy of 69.4% and a mean intersection over union (IoU) of 48.6% when evaluating the trained models on our test set. The models had difficulty distinguishing the background from wounded areas. As an example, image pixels showing subcutaneous hematomas or skin abrasions were assigned to the background class in 31% of cases. Stab wounds, on the other hand, were reliably classified with a pixel accuracy of 93%. These results can be partially attributed to undefined wound boundaries for some types of injuries, such as subcutaneous hematoma. However, despite the large class imbalance, we demonstrate that the best trained models could reliably distinguish among seven of the most common wounds encountered in forensic medical investigations

Sperm hunting on optical microscope slides for forensic analysis with deep convolutional networks – a feasibility study

Microscopic sperm detection is an important task in sexual assault cases. In some instances, the samples contain no or only low amounts of semen. Therefore, the biological material is transferred onto a glass slide and needs to be manually scanned using an optical microscope. This work can be very time consuming, especially when no spermatozoa is present. In such a case, the result needs to be validated. In this article we show how convolutional neural networks can perform this task and how they can reduce the scanning time by locating the sperm cells on images taken under the microscope. For this purpose, we trained a VGG19 network and a VGG19 variation with 1942 images, some containing sperm cells and some not

Augmented Reality in Forensics and Forensic Medicine - Current Status and Future Prospects

Forensic investigations require a vast variety of knowledge and expertise of each specialist involved. With the increase in digitization and advanced technical possibilities, the traditional use of a computer with a screen for visualization and a mouse and keyboard for interactions has limitations, especially when visualizing the content in relation to the real world. Augmented reality (AR) can be used in such instances to support investigators in various tasks at the scene as well as later in the investigation process. In this article, we present current applications of AR in forensics and forensic medicine, the technological basics of AR, and the advantages that AR brings for forensic investigations. Furthermore, we will have a brief look at other fields of application and at future developments of AR in forensics