Cystitis cystica and recurrent urinary tract infections in children

The pathogenesis of recurrent urinary tract infections (UTIs) in preschool children with anatomically correct urinary tract (UT) is rather obscure. In girls, the bladder wall changes of cystitis cystica (CC) may be per se responsible for UTIs recurrence. During the 20-year period, 127 preschool children (125 girls; median age: 6.1 years) with CC, in whom UT anomalies were excluded, were diagnosed. The mean duration of UTIs symptoms prior to diagnosis was 3.31 +/- 2.51 years. Cystoscopical findings were labelled as mild, moderate and severe in 22.8%, 39.4% and 37.8% of patients, respectively. Following the confirmation of CC, long-term chemoprophylaxis with sulfamethoxazole-trimethoprim/nitrofurantoin was administered. A one year UTI-free period after chemoprophylaxis discontinuation was defined as therapeutic success. With 2.5 years median duration of regular chemoprophylaxis this goal was achieved in 58 children mainly with mild/ moderate CC. Thirty children from "improved/unchanged" group taking regular prophylaxis had significant reduction of UTIs ("improved"). Only 12 children belonging to the same group taking regular prophylaxis and all children with irregular prophylaxis had approximately the same number of UTIs as before treatment ("unchanged"). The "improved/unchanged" outcomes were predominantly found in children with severe form of CC. Although urodynamic disturbances detected in more than 50% of patients in whom urodynamics was performed were not found influential on the disease outcome, they could be responsible for its development. The results of our study suggest that regular and long-lasting chemoprophylaxis remains a basis for successful treatment for majority of patients with CC, even those with severe forms. If not treated properly with chemoprophylactic agents and without fair compliance in taking drugs, the disease is prone to recurrent UTIs.     

Beyond the GTP-cap: Elucidating the molecular mechanisms of microtubule catastrophe

Almost 40 years since the discovery of microtubule dynamic instability, the molecular mechanisms underlying microtubule dynamics remain an area of intense research interest. The “standard model” of microtubule dynamics implicates a “cap” of GTP-bound tubulin dimers at the growing microtubule end as the main determinant of microtubule stability. Loss of the GTP-cap leads to microtubule “catastrophe,” a switch-like transition from microtubule growth to shrinkage. However, recent studies, using biochemical in vitro reconstitution, cryo-EM, and computational modeling approaches, challenge the simple GTP-cap model. Instead, a new perspective on the mechanisms of microtubule dynamics is emerging. In this view, highly dynamic transitions between different structural conformations of the growing microtubule end – which may or may not be directly linked to the nucleotide content at the microtubule end – ultimately drive microtubule catastrophe.     

Risk factor analysis and diagnoses of coronary heart disease in patients with hypercholesterolemia from Croatian Zagorje County

Our aim is to determine if there exists a difference in risk factors and diagnosis between patients being treated on internal medicine ward for coronary heart disease who have higher levels of cholesterol in their blood and other patients, without proved higher levels of cholesterol, hospitalized for coronary heart disease. We followed patients hospitalized in General Hospital Zabok for coronary heart disease for the period between 2004-2006y. On admission patients were diagnosed with coronary heart disease based on laboratory markers specific for the disease (CK, troponin, LDH,CRP), ECG and history taking. We analyzed two groups of patients for diagnosis and risk factors on discharge from the hospital: one group with proven hypercholesterolemia, the other with coronary heart disease without hypercholesterolemia. For the duration of the study there were no significant alternations concerning risk factors for coronary heart disease, and hypertension was the most prevalent of these factors in both groups. Values of HDL, as an indirect indicator of coronary heart disease, were lower in both groups for the duration of the study. In group of patients with hypercholesterolemia myocardial infarction with a ST segment elevation, as a discharge diagnosis, was a more prevalent complication of the disease, while for the group of patients without hypercholesterolemia stable angina pectoris was more prevalent and this is explained as atheroma plaque stabilization when there are normal values of blood cholesterol.     

Characterization of lipid domains in reconstituted porcine lens membranes using EPR spin-labeling approaches

The physical properties of membranes derived from the total lipid extract of porcine lenses before and after the addition of cholesterol were investigated using EPR spin-labeling methods. Conventional EPR spectra and saturation-recovery curves indicate that the spin labels detect a single homogenous environment in membranes before the addition of cholesterol. After the addition of cholesterol (when cholesterol-to-phospholipid mole to mole ratio of 1.55-1.80 was achieved), two domains were detected by the discrimination by oxygen transport method using a cholesterol analogue spin label. The domains were assigned to a bulk phospholipid-cholesterol bilayer made of the total lipid mixture and to a cholesterol crystalline domain. Because the phospholipid analogue spin labels cannot partition into the pure cholesterol crystalline domain, they monitor properties of the phospholipid-cholesterol domain outside the pure cholesterol crystalline domain. Profiles of the order parameter, hydrophobicity, and oxygen transport parameter are identical within experimental error in this domain when measured in the absence and presence of a cholesterol crystalline domain. This indicates that both domains, the phospholipid-cholesterol bilayer and the pure cholesterol crystalline domain, can be treated as independent, weakly interacting membrane regions. The upper limit of the oxygen permeability coefficient across the cholesterol crystalline domain at 35 degrees C had a calculated value of 42.5 cm/s, indicating that the cholesterol crystalline domain can significantly reduce oxygen transport to the lens center. This work was undertaken to better elucidate the major factors that determine membrane resistance to oxygen transport across the lens lipid membrane, with special attention paid to the cholesterol crystalline domain.     

The case of asymptomatic primary actinomycosis of the greater omentum in the patient with intrauterine contraceptive device

This paper describes a case of asymptomatic multifocal actinomycosis of the greater omentum which was detected accidentally in a patient who was suspected of uterus myoma. The patient was a 40 year old woman who had a copper intrauterine contraceptive device (IUCD) for three years. After the gynecological examination and pelvic ultrasound she was diagnosed with sub serous myoma of uterus. Since she did not give a birth it was suggested to have myoma enucleating. However during the surgery a dermoid teratoma of the right ovary was detected so it was removed together with tumor and there were two thickenings on the greater omentum, suspicious of inflammation, whereas one grew together with the front abdominal wall. Due to these conditions, she had partial omentectomy done and omentum was sent for path histological examination. The path histological examination confirmed it to be actinomycosis. The patient had an intensive antibiotic therapy prescribed (Penicillin) in order to prevent a disease relapse because we could not be sure whether the remaining part of omentum was affected by microscopic actinomycosis.     

Modification of quercetin with l-cysteine by horseradish peroxidase

Horseradish peroxidase is a well-known member of the peroxidase family that catalyzes oxidation of flavonoids and phenolic substrates to free phenoxyl or semiquinone radicals. Aim of this study was to investigate in vitro oxidation of quercetin by horseradish peroxidase in the presence of l-cysteine as nucleophilic agent, and its influence on previously formed semiquinone- and quinone-type metabolites. The obtained results showed that in the reaction without l-cysteine several products were present, such as quercetin quinone methide, phloroglucinol carboxylic acid, protocatechuic acid, as well as quercetin heterodimer and derivates of quercetin heterodimer. On the other hand, in the presence of l-cysteine only three products were obtained, quercetin quinone methide and two new isomeric mono-cysteine derivatives of quercetin with mass exp. m/z 420.04?±?0.1 [quercetin?+?cysteine–H]^– (theor. m/z 420.0389 [quercetin?+?cysteine–H]^–).     

Host and bacterial factors that regulate LC3 recruitment to Listeria monocytogenes during the early stages of macrophage infection

Listeria monocytogenes is a bacterial pathogen that can escape the phagosome and replicate in the cytosol of host cells during infection. We previously observed that a population (up to 35%) of L. monocytogenes strain 10403S colocalize with the macroautophagy marker LC3 at 1 h postinfection. This is thought to give rise to spacious Listeria-containing phagosomes (SLAPs), a membrane-bound compartment harboring slow-growing bacteria that is associated with persistent infection. Here, we examined the host and bacterial factors that mediate LC3 recruitment to bacteria at 1 h postinfection. At this early time point, LC3⁺ bacteria were present within single-membrane phagosomes that are LAMP1⁺. Protein ubiquitination is known to play a role in targeting cytosolic L. monocytogenes to macroautophagy. However, we found that neither protein ubiquitination nor the ubiquitin-binding adaptor SQSTM1/p62 are associated with LC3⁺ bacteria at 1 h postinfection. Reactive oxygen species (ROS) production by the CYBB/NOX2 NADPH oxidase was also required for LC3 recruitment to bacteria at 1 h postinfection and for subsequent SLAP formation. Diacylglycerol is an upstream activator of the CYBB/NOX2 NADPH oxidase, and its production by both bacterial and host phospholipases was required for LC3 recruitment to bacteria. Our data suggest that the LC3-associated phagocytosis (LAP) pathway, which is distinct from macroautophagy, targets L. monocytogenes during the early stage of infection within host macrophages and allows establishment of an intracellular niche (SLAPs) associated with persistent infection.