Nonactivated titanium-dioxide nanoparticles promote the growth of Chlamydia trachomatis and decrease the antimicrobial activity of silver nanoparticles.

AIMS: Chlamydia trachomatis and herpes simplex virus (HSV) are the most prevalent bacterial and viral sexually transmitted infections. Due to the chronic nature of their infections, they are able to interact with titanium-dioxide (TiO2 ) nanoparticles (NPs) applied as food additives or drug delivery vehicles. The aim of this study was to describe the interactions of these two prevalent pathogens with the TiO2 NPs. METHODS AND RESULTS: Chlamydia trachomatis and HSV-2 were treated with nonactivated TiO2 NPs, silver NPs and silver decorated TiO2 NPs before infection of HeLa and Vero cells. Their intracellular growth was monitored by quantitative PCR. Unexpectedly, the TiO2 NPs (100 µg ml-1 ) increased the growth of C. trachomatis by approximately fourfold, while the HSV-2 replication was not affected. Addition of TiO2 to silver NPs decreased their antimicrobial activity against C. trachomatis up to 27·92-fold. CONCLUSION: In summary, nonactivated TiO2 NPs could increase the replication of C. trachomatis and decrease the antimicrobial activity of silver NPs. SIGNIFICANCE AND IMPACT OF THE STUDY: The food industry or drug delivery use of TiO2 NPs could enhance the growth of certain intracellular pathogens and potentially worsen disease symptoms, a feature that should be further investigated.

Bile acids inhibit Na⁺/H⁺ exchanger and Cl⁻/HCO3⁻ exchanger activities via cellular energy breakdown and Ca²âº overload in human colonic crypts.

Bile acids play important physiological role in the solubilisation and absorption of dietary lipids. However, under pathophysiological conditions, such as short bowel syndrome, they can reach the colon in high concentrations inducing diarrhoea. In this study, our aim was to characterise the cellular pathomechanism of bile-induced diarrhoea using human samples. Colonic crypts were isolated from biopsies of patients (controls with negative colonoscopic findings) and of cholecystectomised/ileum-resected patients with or without diarrhoea. In vitro measurement of the transporter activities revealed impaired Na⁺/H⁺ exchanger (NHE) and Cl⁻/HCO3⁻ exchanger (CBE) activities in cholecystectomised/ileum-resected patients suffering from diarrhoea, compared to control patients. Acute treatment of colonic crypts with 0.3 mM chenodeoxycholate caused dose-dependent intracellular acidosis; moreover, the activities of acid/base transporters (NHE and CBE) were strongly impaired. This concentration of chenodeoxycholate did not cause morphological changes in colonic epithelial cells, although significantly reduced the intracellular ATP level, decreased mitochondrial transmembrane potential and caused sustained intracellular Ca²âº elevation. We also showed that chenodeoxycholate induced Ca²âº release from the endoplasmic reticulum and extracellular Ca²âº influx contributing to the Ca²âº elevation. Importantly, our results suggest that the chenodeoxycholate-induced inhibition of NHE activities was ATP-dependent, whereas the inhibition of CBE activity was mediated by the sustained Ca²âº elevation. We suggest that bile acids inhibit the function of ion transporters via cellular energy breakdown and Ca²âº overload in human colonic epithelial cells, which can reduce fluid and electrolyte absorption in the colon and promote the development of diarrhea.

The effects of hypokalaemia on the hormone exocytosis in adenohypophysis and prolactinoma cell culture model systems.

The extracellular ion milieu determines the exocytosis mechanism that is coupled to spontaneous electrical activity. The K(+) ion plays crucial role in this mechanism: as the potassium current is associated with membrane hyperpolarization and hormone release through protein cascade activation. The primary aim of this study was to investigate the response mechanisms of normal adenohypophysis and adenohypophyseal prolactinoma cell populations at different extracellular K(+) levels with an otherwise isoionic milieu of all other essential ions. We focused on prolactin (PRL) and adrenocorticotrophic hormone (ACTH) release.In our experimental study, female Wistar rats (n=20) were treated with estrone-acetate (150 µg/kg b.w./week) for 6 months to induce prolactinomas in the adenohypophysis. Primary, monolayer cell cultures were prepared by enzymatic and mechanical digestion. PRL and ACTH hormone presence was measured by radioimmunoassay or immuno-chemiluminescence assay. Immunocytochemistry was used to assess the apoptotic cells.Differences between the effects of hypokalaemia on normal adenohypophysis cultures and prolactinoma cell populations were investigated. Significant alteration (p<0.001, n=10) in hormone exocytosis was detected in K(+) treated adenohypophyseal and prolactinoma cell cultures compared to untreated groups. Immunocyto-chemistry showed that Bcl-2 expression was reduced under hypokalaemic conditions.The decrease in hormone exocytosis was tightly correlated to the extracellular K(+) in both cell types, leading to the conclusion that external K(+) may be the major factor for the inhibition of hormone release. The significant increase in hormone content in supernatant media suggests that hypokalaemia may play important role in apoptosis.

[Ultrastructural study of bronchial mucosa in suspicion of ciliary dyskinesia]. / A hörgónyálkahártya ultrastrukturális vizsgálata ciliaris dyskinesia gyanúja esetén.

In the ciliary dyskinesia (immotile cilia syndrome) shows the partial or total lacking of cilia's elements. The ciliary dyskinesia may be developed congenital or acquired. The authors report on the experience with 72 biopsies from bronchial mucosa of 68 children, submitted with the question of immotile cilia syndrome. On micrographs (M: 64,000x) of the specimens processed by routine electron microscopical method the number of outer and inner dynein arm, A and B peripheral tubules, central tubules and central sheet were determined to normal 9 + 2 structure. 50-100 ciliaris per case were examined. Total or partial lacking of dynein and non-dynein elements were expressed for the total number of ciliaris compartments. Considering any earlier quantitative examination with this expression there was ease to characterised the quantitative behaviour of the components of ciliaris. Seven Kartagener's syndrome cases was the positive control for determined the quantitative differences between the primer and secondary ciliary changes. In the primary ciliary defects where the situs inversus were presented the total lacking of outer or/and inner dynein arms, where the situs inversus were not presented only the total lacking of inner dynein arms could be found. In secondary ciliary defects the partial lacking of the dynein arms and tubular components were presented. The used method is suitable to characterise the primary or secondary ciliary defects of bronchial mucosa.

Effects of cinnarizine on different experimentally induced oedemas.

Experiments with male mice (28-32 g) of the CFLP strain showed that cinnarizine in doses of 2.5, 5.0 or 10.0 mg kg-1 significantly inhibited the extent of ear oedema induced by croton oil, capsaicin or dithranol, in a dose-dependent manner. In rats of the Wistar strain, oedema was induced in the hind paw by subplantar injection of carrageenin, and simultaneously by the application of croton oil to the inner surface of the ear. Preliminary cinnarizine treatment (5, 10 or 20 mg kg-1) inhibited the development of both types of oedema, to a statistically significant extent, in a dose-dependent manner.

Endothelial permeability of the afferent arteriole and its changes as the result of alteration in the activity of the renin-angiotensin system.

Recent studies have demonstrated fenestrations in the juxtaglomerular part of the afferent arteriole facing the extraglomerular mesangium and the epithelioid cells in different mammals including humans. The permeability of the endothelium in afferent arteriole may play an important role in various physiologic and pathophysiologic processes. This study therefore was conducted to examine the permeability along the length of afferent arteriole using ferritin particles as an indicator of permeability/fenestration. Assuming the presence of a relationship between the development of permeable endothelial fenestration and renin formation, the permeability of the endothelium and renin granulation and their correlation along the wall of the afferent arteriole under control conditions and during inhibition of renin-angiotensin system by converting enzyme inhibition or AT1 receptor blockade were examined. The intra-aortically administered ferritin particles appeared in the interstitium of the distal part of the afferent arterioles. About one-third to half of the length of the afferent arteriole wall was ferritin-positive. There was a correlation between ferritin-positive and renin-positive portions. The density of ferritin particles was high close to the glomerulus and decreased continuously, similar to the profile of renin distribution. There was also a correlation between ferritin density in basal membrane and the renin granulation index. On the basis of these results, the afferent arteriole, according to its endothelial permeability, can be divided into two distinct portions, i.e., the permeable and the nonpermeable, the length and ratio of which may be related to the actual renin formation. These portions not only are different in the presence or absence of fenestration of the endothelium, but they also show difference in myosin and renin contents, suggesting that each portion may serve different function(s).

Coinhibition of immune and renin-angiotensin systems reduces the pace of glomerulosclerosis in the rat remnant kidney.

The development of progressive glomerulosclerosis (GS) has been attributed to a number of humoral and hemodynamic factors, however, neither the exact pathomechanism nor the prevention and treatment have been clearly established. Renin-angiotensin system (RAS), interleukin-2 (IL-2)-activated T cells, systemic BP, and serum lipid levels all have been recognized as pathogenetic factors. According to our working hypothesis, a combination therapy with the inhibition of RAS and IL-2 system may be more potent in the prevention of the progression of GS than a monotherapy. After 5/6 subtotal nephrectomy, rats were treated with either the angiotensin-converting enzyme-blocker enalapril (E), the angiotensin II AT1 receptor blocker candesartan cilexetil (CA), the IL-2 synthesis inhibitor tacrolimus (T), or a combination of these agents. Proteinuria, as a functional hallmark of GS, was determined regularly, and at week 16, systolic BP, plasma total cholesterol, and triglyceride (TG) levels were measured and kidneys were harvested for morphologic and immunohistochemical analysis. Combination therapy was more effective (proteinuria: CA + T: 29.3+/-12.8 mg/24 h, E + T: 31.3+/-13.0 mg/24 h; GS: CA + T: 10.7+/-4.1%, E + T: 8.3+/-4.6%, P < 0.01) than monotherapy (proteinuria: T: 49.3+/-17.3 mg/24 h, CA: 53.2+/-18.1 mg/24 h, E: 51.1+/-26.6 mg/24 h; GS: T: 10.9+/-4.4%, CA: 23.8+/-4%, E: 14.2+/-5.3%, P < 0.05, with control values of proteinuria: 77.6+/-27.1 mg/24 h and GS: 28+/-2.9%). The number of infiltrating ED-1 (rat macrophage marker) macrophages (T: 161.5+/-51.2 cells/field of view, CA: 203.6+/-102.3, E: 178.6+/-35.3, CA + T: 140.2+/-63.2, E + T:128.2+/-75.6), and CD-5+ (rat T cell marker) T lymphocytes (CA + T: 261.5+/-103.6, E + T: 236+/-94.8) was significantly reduced by the treatment protocols (controls: ED-1: 356+/-100, CD-5: 482.9+/-154.5). These results indicate that an inhibition of RAS either with angiotensin-converting enzyme or AT1 receptor blockade, together with the inhibition of IL-2 synthesis, is more effective in the prevention of GS than a single treatment alone.

TNF inhibits myogenesis and downregulates the expression of myogenic regulatory factors myoD and myogenin.

The presence of TNF and other inflammatory cytokines and their receptors is detected during embryonic development, but our knowledge about the role of these proteins in differentiation and development is very limited. TNF modulates the synthesis and activity of a number of transcriptional proteins that regulate the activity of tissue specific genes, therefore it may play a role in normal development. Since its synthesis is upregulated by stress and infections, it may also participate in the induction of pathological developmental processes and malformation. We investigated the effect of TNF in an in vitro differentiation system using C2 myoblasts. This inflammatory cytokine exerted a positive effect on the early steps of the process: it enhanced the proliferation and aggregation of myoblast cells. In contrast, TNF strongly inhibited the expression of those myogenic transcription factors (myoD and myogenin), which are known to be responsible for upregulated activity of muscle specific genes (like the genes of the myofilament proteins), and blocked the synthesis of mRNAs of myogenic differentiation markers (like skeletal alpha-actin, myosin heavy and light chains). As a result, these cells did not synthesize myofilament proteins and the organization of myofilaments did not take place in TNF-treated myoblasts.

Quantitative ultrastructural study of afferent and efferent arterioles in IgA glomerulonephritis and benign nephrosclerosis.

Arteriolosclerosis frequently occurs in IgA nephritis (IgAN), and it is the hallmark of benign nephrosclerosis (BNS). The quantitative ultrastructure of juxtaglomerular arterioles is not known in these disorders. We examined afferent and efferent arterioles in renal biopsies from 25 adult patients with IgAN (hypertension at biopsy: 14 patients) and 9 patients with BNS. Six age-matched living renal transplant donors acted as controls. A systematic independent sample of profiles was obtained in thin sections taken at predetermined levels. The thickness of the media (myomedial cells plus the matrix) and the thickness of the medial matrix were estimated stereologically. From these estimates, the matrix/myomedia ratio was calculated. In IgAN with normotension or hypertension, the afferent media and its compartments did not exhibit significant thickening compared with the controls, whereas in BNS the afferent media and its layers were markedly and significantly thickened. The efferent media in IgAN and BNS displayed mild and significant thickening, with significant thickening of the matrix in BNS and IgAN with normotension. The matrix/myomedia ratio was not altered significantly in any group. The results indicate that the afferent arterioles are not the main sites of IgAN-related arteriolosclerosis, that arteriolosclerosis in IgAN and arteriolosclerosis in BNS are different lesions, and that increased efferent arteriolar thickness, demonstrated here for the first time in IgAN and BNS, might be a manifestation of angiotensin II-mediated autoregulatory efferent vasoconstriction exerted to maintain the glomerular filtration pressure.

[Anti-edematous effects of cinnarizine]. / A cinnarizin ödémagátló hatásának vizsgálata.

Experiments carried out with male mice (28-32 g) of CFLP strain have shown that cinnarizine significantly inhibits the extents of ear oedema induced by croton oil or capsaicin. In rats of Wistar strain, oedema was induced in the hind paw by subplantar injection of carrageenin, and simultaneously by the application of croton oil to the inner surface on the ear. Preliminary cinnarizine treatment inhibited the development of both types of oedema, to statistically significant extent.

Ultrastructural characteristics of glial fibrillary acidic protein expression in epoxy resin-embedded human brain tumors.

Thirteen surgically removed, epoxy resin (Durcupan ACM or Epon 812)-embedded human brain tumors were examined for glial fibrillary acidic protein (GFAP) content in semithin and ultrathin sections with the immunogold-silver staining method. Mild aldehyde fixation and the hydrophobic resin embedding did not interfere with the antigenicity, since silver intensification of the immunogold marker provided excellent visualization of the reaction on both light microscopic and ultrastructural levels. The GFAP reaction was usually localized on the glial intermediate filament bundles, usually correlating well with the amount of filaments. The unstained filamental regions of two ependymomas might correspond to the vimentin expression revealed by double labeling in semithin sections. Occasional GFAP immunopositivity without filamental appearance was observed in one of the oligodendrogliomas, as patchy electron-dense cytoplasmic corpuscules, in Rosenthal fibers and in some mainly necrobiotic tumor cells, reflecting a possible connection with glial filaments.

Development and inhibition of mouse ear oedema induced with capsaicin.

Oedema was induced in one ear of male mice of the CFLP strain with capsaicin solution (10 microliters/40 micrograms/ear). The development in time and the extent of the oedema were determined by the oedema-disk gravimetric technique. The maximum oedema was attained in less than 1 h, and there was, subsequently, a gradual decrease. The extent of the mouse ear oedema induced in this way and measured after 60 min was inhibited to a statistically significant degree and in a dose-dependent manner by the antihistamine chloropyramine, the antihistamine-antiserotonin cyproheptadine, the non-steroidal anti-inflammatory agent piroxicam, the prostaglandin antagonist di-4-phloretin phosphate, and the lipoxygenase inhibitor nordihydroguairetic acid. The method proved suitable for the detection of oedema and for the biologically quantitative determination of the state of desensitization induced with capsaicin.

[Anti-edema effects of some H1-receptor antagonists]. / H1-receptor antagonisták ödémagátló hatása.

Experiments carried out with mice of CFLP strain have shown that antihistaminics (chloropyramine, cyproheptadine and dimethindene maleate) significantly inhibit the extents of ear oedema induced by croton oil, dithranol or capsaicin. In rats of Wistar strain, oedema was induced in the hind paw by the subplantar injection of carrageenin, and simultaneously by the application of croton oil to the inner surface on the ear. Preliminary antihistamine treatment inhibited the development of both types of oedema, to statistically significant extent.

[Capsaicin-induced mouse ear edema and its management]. / Kapszaicinnel elöidézett egérfül-ödéma és befolyásolása.

Oedema was induced in one ear of male mice of the CFLP strain with capsaicin solution (10 microliters/40 micrograms/ear). The development in time and the extent of the oedema were determined by the oedema-disk gravimetric technique. The maximum oedema was attained after 1 hour, and there was subsequently a gradual decrease. The extent of the mouse ear oedema induced in this way and measured after 60 minutes was inhibited to a statistically significant degree and in a dose-dependent manner by the antihistamine chloropyramine, the antihistamine-antiserotonin cyproheptadine, the non-steroidal antiinflammatory agent pyroxicam, the prostaglandin antagonist di-4-phloretin phosphate, and the lipoxygenase inhibitor nordihydroguaiaretic acid. The method proved suitable for the detection and biologically quantitative determination of the state of desensitization induced with capsaicin.

Morphological characterization of human juxtaglomerular apparatus.

The recent demonstration of the endothelial fenestration at the juxtaglomerular part of the afferent arteriole facing mesangial and granular cells and finger-like protrusions of urinary space into the region of the lacis in experimental animals like the rat, the mouse, and Tupaia belangeri led us to propose the hypothesis of a "short loop" feedback mechanism. To establish whether a further species possesses these morphological features, the JGA region was examined in the human kidney. Tissue was obtained by needle biopsy from patients and conventional electron-microscopical procedures including serial sections were utilized to reevaluate the morphology of JGA. Both the endothelial fenestration in the wall of the afferent arteriole and protrusions with filtration slits of urinary space into the lacis, were observed with remarkable heterogeneity. The occurrence of these features of JGA in such diverse mammalian species as rat, mouse, Tupaia, and man suggests that these structures may be involved in regulatory process and the proposed "short loop" feedback mechanism may be a general phenomenon.

Effect of benzopyrone derivatives on simultaneously induced croton oil ear oedema and carrageenin paw oedema in rats.

Carrageenin paw oedema and croton oil ear oedema induced simultaneously in rats are inhibited in a dose-dependent manner and to statistically significant degrees by lipoxygenase- and cyclooxygenase-blocker flavonoids (diosmin, fisetin, quercetin, myricetin, galangin, sophoricoside, hesperidin-methylchalcone, oligomeric procyanidin, anthocyanidins (delphinidin, pelargonidin], and the prostaglandin antagonist polyphloretin phosphate and di-4-phloretin phosphate. Outstanding anti-inflammatory effects are displayed by myricetin and delphinidin, which contain vicinal hydroxy groups in ring B. The results confirm the importance of hydroxy group substitution in ring B. The most effective of the examined substances proved to be the prostaglandin antagonist di-4-phloretin phosphate.

Effects of non-steroidal antiphlogistics on mouse ear oedema induced with dithranol.

Mouse ear oedema induced with dithranol in mice of the CFLP strain was decreased significantly, in a dose-dependent manner, by the oral administration of the following non-steroids 60 minutes before induction of the oedema: piroxicam, proquazone, azapropazone, nifluminic acid and phenylbutazone. An approximately 50% inhibitory effect could be attained with the following doses: 3.3 mg/kg piroxicam, 5 mg/kg proquazone, 5 mg/kg azapropazone, and 1 mg/kg nifluminic acid. Administration of the largest dose (30 mg/kg) of phenylbutazone, used for comparison, resulted in an oedema decrease of 41%.

The acenocoumarol-carrageenin test.

Rats received a single subcutaneous dose of the inflammatory agent carrageenin on the top of the skull, followed by oral acenocoumarol for 3 days; in every case, an extensive haematoma was observed on the skull on day 4. The capillary resistance on the depilated dorsal skin was significantly reduced by this combined inflammatory + anticoagulant treatment. Haematoma development was not inhibited by cortisone, non-steroidal anti-phlogistics (piroxicam, proquazone) or benzopyrone derivatives (hesperidin methylchalcone, oligomeric procyanidin). On pretreatment with vitamin K1 for 1 day, followed by daily treatment for 3 days, no haematoma was observed.

[Edema inhibiting effect of indenochromene derivatives from natural sources]. / Természetes eredetü indenokromen-származékok ödémagátló hatása.

Experiments carried out with rats of Sprague-Dawley CFY strain have shown that indenochromene derivatives (brasilin, hematoxylin, hematein) inhibit significantly paw oedema of rats induced by carrageenin. Foot oedema produced by dextran has only decreased after application of hematein. Generalized dextran oedema, i. e. thermic oedema has significantly decreased after application of brasilin and hematoxylin. Experiments carried out with mice of CFLP strain have proved that indenochromene derivatives--even in small quantities--decrease ear oedema produced by dithranol statistically in a great extent.