Chronic administration of quercetin induces biomechanical and pharmacological remodeling in the rat coronary arteries.

Acute dilation brought about by the dietary flavonoid quercetin in coronary arterioles has been described earlier, but no information is available on its chronic effects. Male Wistar rats (body weight about 190 g) were divided to two groups: the quercetin-treated group (n=22) had quercetin supplementation of approximately 30 mg/kg/day, whereas the control group (n=20) had none. After eight weeks of treatment, intramural coronary arterioles with identical passive diameters (178+/-14 microm and 171+/-9 microm) were prepared and their biomechanics and pharmacological reactivities were tested using pressure arteriography ex vivo. The spontaneous tone of quercetin-treated arteries was higher (16.5+/-1.9 % vs. 12.9+/-0.9 %), which resulted in a reduced lumen size (144+/-9 microm vs. 167+/-12 microm), thicker vascular wall (22.6+/-1.8 microm vs. 17.4+/-1.6 microm) and decreased tangential wall stress (16.8+/-1.1 kPa vs. 20.5+/-1.6 kPa) in supplemented animals (in spontaneous tone at 50 mm Hg, p<0.01 in all these comparisons). Elevated basal NO release resulted in increased endothelial dilation in quercetin-treated animals, especially at higher intraluminal pressures (10.8+/-2.5 % vs. 5.7+/-1.3 % at 70 mm Hg, p<0.01). We found remodeling of the geometry of coronary arterioles to ensure higher dilatory reserve and nitrogen monoxide production, as well as lowered elastic stress of the vessel wall.

The investigation of interspecies diversity of erythrocyte aggregation properties by two different photometric methods in four animal species.

Among the haemorheological parameters, red blood cell (RBC) aggregation shows the largest interspecies diversity, and often controversial data can be found in the literature, besides the methodology-dependent issues. In this present investigation, we compared four experimental/laboratory animal species' RBC aggregation by two different photometric methods for better revealing the differences. Blood samples (K3-EDTA, 1.5 mg/ml) were taken from female animals: 16 inbred mice (Mus musculus, cardiac puncture), 15 outbred rats (Rattus norvegicus, caudal caval vein puncture), 15 beagle dogs (Canis canis, cephalic vein) and 23 juvenile pigs (Sus scrofa domesticus, medial saphenous vein). Haematological parameters (microcell counter) and RBC aggregation (light transmission and syllectometry-laser backscatter methods) were determined within 2 h after sampling. Describing the first 5-10 s of the aggregation process, additional parameters were calculated out of the syllectometric raw data. Standardized difference was calculated to determine the sensitivity of the two devices. Parameters describing the extent and magnitude of red blood cell aggregation showed the lowest values in the rat and the highest in the pig and canine blood. In turn, parameters describing the kinetics of aggregation showed the lowest values in the mouse and the highest in the rat. The standardized difference values for the laser backscattering method were 2-4 times larger vs. the light transmission one. The magnitude of the differences was not consequent in the aggregation parameters. These comparative results show that the laser backscattering method can detect the RBC aggregation differences between the investigated species more sensitively than the light transmission method.

Influence of peripheral vascular calcification on efficiency of screening tests for peripheral arterial occlusive disease in diabetes--a cross-sectional study.

AIMS: Pulse palpation and ankle brachial index are recommended to screen for peripheral arterial occlusive disease in people with diabetes. However, vascular calcification can be associated with false negative tests (arteriopathy present despite normal screening tests). We therefore studied the impact of peripheral vascular calcification on the performance of these tests. METHODS: This cross-sectional study included 200 people with diabetes at high risk of cardiovascular disease. The main exclusion factor was an estimated glomerular filtration rate < 30 ml/min. Peripheral arterial occlusive disease was diagnosed by colour duplex ultrasonography and peripheral vascular calcification scored by computed tomography scan. We measured sensitivity, specificity, predictive values, accuracy and likelihood ratios of pulse palpation and ankle brachial index, and looked for the impact of calcification on false negative tests (arteriopathy present despite normal screening tests). RESULTS: Ankle brachial index alone had poor sensitivity and negative predictive value and high negative likelihood ratio. Pulse palpation had higher sensitivity and negative predictive value. An abnormal pulse palpation, defined by weak or missing pulses, combined with an abnormal ankle brachial index, had the highest sensitivity and negative predictive value (92.3 and 89.8%, respectively). Vascular calcification score was higher in patients with false negative tests, for both pulse palpation and ankle brachial index (P < 0.0001 for all). Ankle systolic blood pressure was higher in patients with false negative tests for pulse palpation (P = 0.004). CONCLUSIONS: Below-knee vascular calcification gave a high rate of false negative results for ankle brachial index. Refined pulse palpation combined with ankle brachial index remained the best strategy to screen for peripheral arteriopathy.

A review of UVB-mediated photosensitivity disorders.

Photosensitivity to UVB is a prominent feature of a small number of congenital skin disorders. In addition UVB may also contribute to the action spectrum of a number of acquired photosensitivity syndromes. The gene mutations underlying the genetically inherited disorders have largely been identified and have provided insights into DNA repair pathways. The pathomechanisms for the acquired disorders are still largely undefined. Few therapeutic options are available so management of all these disorders still relies on rigorous photo-protection.

Changes in a nanoparticle's spectroscopic signal mediated by the local environment.

Using a first-principles theoretical model the adsorption of a methyl radical on different sized silver nanoparticles is compared to the adsorption of the same radical on model surfaces. Calculations of our structural, dynamical and electronic properties indicated that small changes in the local environment will lead to small changes in infrared (IR) wavenumbers, but in dramatic changes in the IR signal. Our calculations indicate the lower the adsorption site coordination, the higher is the signal strength, suggesting that small changes in the electronic charge distribution will result in bigger changes in the polarizability and hence in the spectroscopic signal intensity. This effect explains, among others, the signal magnification observed for nanoparticles in surface enhanced Raman spectroscopic (SERS) experiments.

Cestode genomics - progress and prospects for advancing basic and applied aspects of flatworm biology.

Characterization of the first tapeworm genome, Echinococcus multilocularis, is now nearly complete, and genome assemblies of E. granulosus, Taenia solium and Hymenolepis microstoma are in advanced draft versions. These initiatives herald the beginning of a genomic era in cestodology and underpin a diverse set of research agendas targeting both basic and applied aspects of tapeworm biology. We discuss the progress in the genomics of these species, provide insights into the presence and composition of immunologically relevant gene families, including the antigen B- and EG95/45W families, and discuss chemogenomic approaches toward the development of novel chemotherapeutics against cestode diseases. In addition, we discuss the evolution of tapeworm parasites and introduce the research programmes linked to genome initiatives that are aimed at understanding signalling systems involved in basic host-parasite interactions and morphogenesis.

A review of UVA-mediated photosensitivity disorders.

A number of skin conditions are characterised by photosensitivity to UVA. Some of these are exclusively UVA-mediated conditions, while others include UVA in the action spectrum which also include UVB and/or visible light. This review aims to describe this diverse range of conditions for non-dermatologist scientists with an interest in this topic. As such, clinical details, including treatments, are brief and succinct. Recent advances in understanding the pathogenesis of these conditions is highlighted.

Size effects on silver nanoparticles' properties.

In this work a systematic study of the dependence of the structural, electronic, and vibrational properties on nanoparticle size is performed. Based on our total energy calculations we identified three characteristic regimes associated with the nanoparticle's dimensions: (i) below 1.5 nm (100 atoms) where remarkable molecular aspects are observed; (ii) between 1.5 and 2.0 nm (100 and 300 atoms) where the molecular behavior is influenced by the inner core crystal properties; and (iii) above 2.0 nm (more than 300 atoms) where the crystal properties are preponderant. In all considered regimes the nanoparticle's surface modulates its properties. This modulation decreases with the increasing of the nanoparticle's size.

Mitochondrial function in cell wall glycoprotein synthesis in Saccharomyces cerevisiae NCYC 625 (Wild type) and [rho(0)] mutants.

We studied phosphopeptidomannans (PPMs) of two Saccharomyces cerevisiae NCYC 625 strains (S. diastaticus): a wild type strain grown aerobically, anaerobically, and in the presence of antimycin and a [rho(0)] mutant grown aerobically and anaerobically. The aerobic wild-type cultures were highly flocculent, but all others were weakly flocculent. Ligands implicated in flocculation of mutants or antimycin-treated cells were not aggregated as much by concanavalin A as were those of the wild type. The [rho(0)] mutants and antimycin-treated cells differ from the wild type in PPM composition and invertase, acid phosphatase, and glucoamylase activities. PPMs extracted from different cells differ in the protein but not in the glycosidic moiety. The PPMs were less stable in mitochondrion-deficient cells than in wild-type cells grown aerobically, and this difference may be attributable to defective mitochondrial function during cell wall synthesis. The reduced flocculation of cells grown in the presence of antimycin, under anaerobiosis, or carrying a [rho(0)] mutation may be the consequence of alterations of PPM structures which are the ligands of lectins, both involved in this cell-cell recognition phenomenon. These respiratory chain alterations also affect peripheral, biologically active glycoproteins such as extracellular enzymes and peripheral PPMs.

[Food allergy in patients with respiratory allergy. Diagnostic possibilities and problems]. / Légúti allergiás betegek étalallergiája. Diagnosztikai lehetöségek és problémák.

UNLABELLED: In the past two years the authors examined 28 patients with abdominal complaints and allergic respiratory symptoms. Detailed internal, gastroenterological, allergological examinations were made. METHODS: 1 skin Prick-test (SPT) with inhalative and nutritive panel 2. measuring of food-specific (gliadin, alpha-lactalbumin beta-lactoglobulin, ovalbumin) IgG-antibody level detecting with ELISA method, 3. leukocyte migration inhibition (LMI) test against the same foodstuffs, 4. histological examination of the stomach and the duodenum especially for mucosal mastocytes (MMCs). RESULTS: 1. SPT was positive in 23/28 patients for inhalative, but in the 5 cases we did not identify any inhalative allergen. The SPT for the main foodstuffs were positive in 18 patients while in 3 other patients there was urtica only for the other antigens. 2. The food-specific IgG-antibody level was increased in 18/27 patients against one or more antigens. The SPTs and the antibody determination showed identity in 8/18 cases. 3. The LMI tests were positive against one or more main food-products in 23/27 cases. There was common positivity in respect of antigens (between LMI test and antibody identification) in 17 cases. Pathological immunological reactions were presented against the same main foodstuffs with at least two methods for flour in 11, for egg in 10 and for milk in 12 patients. Endoscopic examinations were performed in 27 cases. The number of the MMCs were increased in 22/27 patients. After a specific elimination diet open-food challenges were performed and they confirmed the results of the in vitro and in vivo examinations. CONCLUSION: It is common that the respiratory allergic symptoms in atopic patients accompanied with food allergy for the main foodstuffs caused not only more severe respiratory symptoms, but abdominal complaints too. In respect to the many positive LMI tests the late-type hypersensitivity have important pathogenetical role in it. This three methods together define well the main food-products, which can be antigens as well. The examination of the MMCs supports the local disturbance in the immunoregulatory system.

[Current viewpoints on the evaluation of testicular biopsy]. / A herebiopsiák értékelésének új szempontjai.

The aim of this study was to analize clinical diagnoses and histopathological reports in 185 cases of male infertility, investigated by testicular biopsies in the period 1993-1997. The classical objective of such investigations has been to clarify either obstructive, or so-called secretory lesions resulting in azoospermia. Histologically normal spermatogenesis was reported in 8 patients (4.3%). Hypospermatogenesis proved to be the most frequent pathologic lesion (69 cases, 37.3%), followed by maturation arrest (61 cases, 33%). Germ cell aplasia (Sertoli-cell-only syndrome) was found in 28 cases (15.1%). Tubular atrophy was the dominant lesion in 5 cases (2.7%). Inflammatory change without other histologic abnormalities was seen only in 1 biopsy (0.5%). Further 13 specimens (7%) showed miscellaneous lesions, including one intratubular germ cell neoplasia. Retrospective histopathologic analysis revealed the coexistence of different basic lesions in 43 of our cases (21.7%). According to the novel requirements, pathologists should always report the presence of germ cell forms in the specimen, which are potentially suitable for fertilization. This is essencial because the new methods of testicular spermium extraction and intracytoplasmatic spermium injection offer the chance of assisted fertilization, even for some patients with smaller testicles and slightly elevated FSH levels.

[Reproducibility of malignancy grading in prostatic cancers using the Gleason-Böckling system]. / A kórszövettani malignitási fokozat Gleason és Böcking-osztályozásának reprodukálhatósága prostatarákokban.

Histologic slides from 50 cases of prostatic adenocarcinoma were evaluated by 5 pathologists, in order to test the reproducibility of grading in two systems. Twenty-five needle core biopsies and 25 surgical (adenomectomy) specimens were graded in two sessions, according to the histomorphologic criteria of Gleason and Böcking. The results were analyzed by the kappa statistics. In surgical specimens, there were no significant differences in the interobserver reproducibility of microscopically assessed categories. In needle biopsies, however, Gleason's primary pattern (62%, kappa = 0.42), and Böcking's histological pattern (63%, kappa = 0.37) showed the highest level of agreement. Among the computed (derivated) classification terms, those consisting of only 3 groups (Gleason grouping, kappa = 0.39; Böcking grade, kappa = 0.39) proved to be better reproducible than the corresponding score values (p < 0.05). When compressing both systems into two grades (high and "non-high"), reproducibility was improved (kappa = 0.52). For a substantial improvement of grading results, more accurate grade definitions, continuing training and regular consultation of pathologists are necessary. Based on the results obtained by intraobserver analysis we conclude that kappa statistics is of limited value when analyzing the role of individual experience at grading reproducibility.

Decomposition of cisplatin in aqueous solutions containing chlorides by ultrasonic energy and light.

Decomposition of cisplatin in an aqueous 0.15 M chloride solution by diffuse daylight, by monochromatic light, and by ultrasonic energy was studied using a new HPLC method. The relative sensitivity of cisplatin to light copies the curve of the absorption spectrum of cisplatin with maximum at ca. 300 nm; however, any light below 500 nm must be avoided. Sonication also leads to a rapid decomposition of cisplatin. Irradiation by diffuse daylight or sonication of the cisplatin solutions for 5 min leads to ca. 1% amminetrichloroplatinate(II). Using HPLC analysis with diode-array spectrophotometric detection, the main decomposition product was identified as amminetrichloroplatinate(II).

Investigation of chromium (VI) tolerant bacteria.

Pseudomonas strains were isolated from a heavy metal contaminated sludge. Some of the strains grew on chromium (VI) containing medium, and others were inhibited in their growth. Cells were able to remove chromium from the medium. This ability was independent of the rate of their growth. The concentration of chromium (VI) of the media decreased with 15-20 ppm in presence of 10(9) cells. The chromium (VI) was converted into a reduced form of chromium by bacteria. The reduced form of chromium was bound in the cell wall. The bound form of chromium could be recovered more or less with different chemicals. The best percentages of recovery were achieved with NaOH solution.

Specific reduction of wheat storage proteins by thioredoxin h.

Gliadins and glutenins, the major storage proteins of wheat endosperm (Triticum durum, Desf. cv Monroe), were reduced in vitro by the NADP/thioredoxin system (NADPH, NADP-thioredoxin reductase and thioredoxin; in plants, the h type) from either the same source or the bacterium Escherichia coli. A more limited reduction of certain members of these protein groups was achieved with the reduced form of glutathione or glutaredoxin, a protein known to replace thioredoxin in certain bacterial and mammalian enzyme systems but not known to occur in higher plants. Endosperm extracts contained the enzymes necessary to reduce NADP by the oxidative pentose phosphate pathway (hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase). The gliadins and glutenins were also reduced in vivo during germination--an event that accompanied their proteolytic breakdown. The results suggest that thioredoxin, reduced by NADPH generated via the oxidative pentose phosphate pathway, functions as a signal in germination to enhance metabolic processes such as the mobilization of storage proteins and, as found earlier, the activation of enzymes.

Separation of some platinum(II) complexes by ionic strength gradient on a solvent-generated ion-exchange sorbent.

The compatibility of ionic strength gradient with solvent-generated ion-exchange chromatography on an octadecylsilica sorbent was proven for a mobile phase containing octanesulphonate. Only a slight baseline shift was observed during the gradient of the phosphate buffer, even at 210 nm. An equilibration time of 3 min between the runs was sufficient to obtain retention times with a reproducibility better than 1%. The compounds separated were cisplatin, carboplatin and related neutral and cationic platinum(II) complexes, including transplatin and the aquation products of cisplatin.