A role of hydrogen peroxide producing commensal bacteria present in colon of adolescents with inflammatory bowel disease in perpetuation of the inflammatory process

Bacteria in the gut play a central role in the initiation and progress of inflammatory bowel disease (IBD). This study was prepared to elucidate the role in the inflammatory process of the bacterial species which are able to produce hydrogen peroxide, present in samples taken from colon lesions in adolescents with inflammatory bowel disease. Fifty eight adolescents were enrolled into the study from January 2004 to October 2006 in Cracow, Poland. Biopsies and stool samples were collected. Bacteriological examinations and measurements of hydrogen peroxide production by enterococci, streptococci and lactobacilli were performed. For the first time it has been shown here that HP producing bacteria may contribute to increased amounts of hydrogen peroxide in the inflamed mucosa of Crohn’s disease and ulcerative colitis patients. Moreover, we have been able to demonstrate an increase of total populations of aerobic bacteria but not anaerobes in the studied samples of mucosa of adolescents with inflammatory bowel disease which is an indirect evidence of higher oxygen tension present in inflamed tissues in IBD. We have also been able to demonstrate the direct relationship between presence of blood in stools of IBD adolescents and increased populations of Enterobacteriaceae but not streptococci in samples of colon mucosa. It is, therefore, possible that different products of Enterobacteriaceae and especially their lipopolysaccharides may also contribute to perpetuation of the chronic colon inflammation

Zakażenia szpitalne oraz nadzór po zakończeniu hospitalizacji w wybranych procedurach chirurgii naczyń

Background. Nosocomial infections are an unwanted complication present in almost every hospital. Among patients of highly specialized departments, including vascular surgery wards, the most prevalent form of clinical infection are Surgical Site Infections (SSIs). SSIs significantly extend the patient's stay in the hospital, increase costs and above all can be the direct cause of death after vascular procedures. Material and methods. This paper presents the results of studies on infection epidemiology in vascular surgery in the years 2002-2006 (9,573 surgical procedures) as well as a targeted study which included 413 patients of two highly specialized wards in the year 2005. The registration of infections was based on definitions formulated on the basis of CDC guidelines, and included postdischarge cases. Results. Within the Active Surveillance System, 207 cases of SSI have been identified (incidence 2.2%) and 99 cases of hospital acquired pneumonia (incidence 1.0%); other forms of infection accounted for 21 cases. The overall incidence among patients undergoing surgical procedures (vascular surgery) was 3.4%. The targeted study allowed for a detailed analysis of SSI incidence with consideration of the SSI standardized infection ratio. The cumulated incidence rate of SSIs was 2.6% in site I and 5.6% in site II. Among the etiological factors isolated from materials taken from patients with symptoms of SSI, staphylococci were in the majority, among them Stapylococcus aureus. In the targeted study, almost half of the isolated S. aureus strains (40%) manifested a resistance to methicillin (MRSA) as well as macrolides, lincosamides and streptogramin B (MLSβ). Conclusions. The Active Infection Surveillance System confirmed that in the patients of the studied population the most prevalent form of infection was SSI; however, a high incidence of hospital acquired pneumonia was also noticed. In the targeted study, the SSI incidence in site no. I was within the expected values. The possibility of performing postdischarge registration of infections was confirmed as well as the purposefulness of systematic infection control conducted by experienced personnel. The study showed the need for an improvement in microbiological surveillance in infection control, as well as the necessity of performing further detailed studies regarding the relationship of the operating team experience to the incidence of SSIs within Polish vascular surgery wards. We claim that in certain cases the division, together with the later reconstruction, of the left renal vein may facilitate the course of reconstructive operation of the abdominal aorta and decreases the risk of haemo-rrhage complications. Moreover, this manoeuvre does not influence postoperative renal function.Wstęp. Zakażenia szpitalne są niepożądanym powikłaniem występującym praktycznie w każdym szpitalu. Wśród pacjentów oddziałów wysokospecjalistycznych, w tym w chirurgii naczyń, dominującą formę kliniczną tych zakażeń stanowią zakażenia miejsca operowanego. W istotny sposób przedłużają one pobyt pacjenta w szpitalu, zwiększają koszty, a przede wszystkim mogą być bezpośrednią przyczyną śmierci chorych po zabiegu w zakresie naczyń. Materiał i metody. Zaprezentowano wyniki badań dotyczących epidemiologii zakażeń w chirurgii naczyniowej w latach 2002-2006 (9573 zabiegi operacyjne) oraz badania celowanego, którym objęto łącznie 413 pacjentów dwóch oddziałów wysokospecjalistycznych w 2005 roku. Rejestracja zakażeń opierała się na definicjach opracowanych na podstawie zaleceń Centers for Disease Control and Prevention (CDC) i uwzględniała przypadki wykryte po zakończeniu hospitalizacji. Wyniki. Wśród dominujących zakażeń szpitalnych w ramach Systemu Czynnego Nadzoru rozpoznano 207 przypadków zakażenia miejsca operowanego (zachorowalność 2,2%) i 99 szpitalnych zapaleń płuc (zachorowalność 1,0%), inne formy zakażeń stanowiły 21 przypadków. Zachorowalność w grupie pacjentów operowanych - chirurgia naczyniowa - wyniosła ogółem: 3,4%. Badanie celowane umożliwiło szczegółową analizę zachorowalności zakażeń miejsc operowanych z uwzględnieniem standaryzowanego indeksu ryzyka. Współczynniki zachorowalności skumulowanej zakażeń miejsc operowanych wyznaczono na poziomie 2,6% w ośrodku I oraz 5,6% w ośrodku II. Wśród czynników etiologicznych izolowanych z materiałów pochodzących od pacjentów z objawami zakażenia miejsca operowanego dominowały gronkowce, a wśród nich gatunek Stapylococcus aureus. W badaniu celowanym prawie połowa z izolowanych szczepów S. aureus (40%) to szczepy oporne na metycylinę (MRSA) oraz makrolidy, linkozamidy i streptograminy B (MLSb). Wnioski. System Czynnego Nadzoru potwierdził, że w badanej populacji pacjentów dominującą formą zakażenia jest zakażenie miejsca operowanego, jednak zaobserwowano również wysoką zachorowalność dotyczącą szpitalnych zapaleń płuc. W badaniu celowanym stwierdzona zachorowalność zakażenia miejsca operowanego w przypadku I pierwszego badanego ośrodka odpowiadała oczekiwanym wartościom. Potwierdzono możliwość prowadzenia rejestracji zakażeń manifestujących się po zakończeniu hospitalizacji chorego oraz celowość systematycznej kontroli zakażeń prowadzonej przez doświadczony personel. Wykazano konieczność poprawy wykorzystania nadzoru mikrobiologicznego w kontroli zakażeń oraz dalszych szczegółowych badań w zakresie związku pomiędzy doświadczeniem zespołu operującego a zachorowalnością na oddziałach chirurgii naczyniowej w Polsce

Studies of discrete symmetries in decays of positronium atoms

A positronium - a bound state of electron and positron - is an eigenstate of parity and charge conjugation operators which decays into photons. It is a unique laboratory to study discrete symmetries whose precision is limited, in principle, by the effects due to the weak interactions expected at the level of 10−14 and photon-photon interactions expected at the level of 10−9. The Jagiellonian Positron Emission Tomograph (J-PET) is a detector for medical imaging as well as for physics studies involving detection of electronpositron annihilation into photons. The physics case covers the areas of discrete symmetries studies and genuine multipartite entanglement. The J-PET detector has high angular and time resolution and allows for determination of spin of the positronium and the momenta and polarization vectors of annihilation quanta. In this article, we present the potential of the J-PET system for studies of discrete symmetries in decays of positronium atoms

TOF-PET detector concept based on organic scintillators

In this contribution we present a new concept of the large acceptance detector systems based on organic scintillators which may allow for simultaneous diagnostic of large fraction of the human body. Novelty of the concept lies in employing large blocks of polymer scintillators instead of crystals as detectors of annihilation quanta, and in using predominantly the timing of signals instead of their amplitudes

Strip- PET : a novel detector concept for the TOF-PET scanner

We briefly present a design of a new PET scanner based on strips of polymer scintillators arranged in a barrel constituting a large acceptance detector. The solution proposed is based on the superior timing properties of the polymer scintillators. The position and time of the reaction of the gamma quanta in the detector material will be determined based on the time of arrival of light signals to the edges of the scintillator strips