Proton conductivity of imidazole entrapped in microporous molecular sieves.

Imidazole embedded in molecular sieves shows remarkable and steady proton conductivity (>1 × 10-5 S cm-1 above 360 K). It can be considered to be a promising solid high proton conducting electrolyte for fuel cells. The conductivity depends on imidazole loading and mobility, which result from the pore geometry, the chemical nature of matrices and the preparation method.

Comparison of antifungal activity of extracts from different Juglans regia cultivars and juglone.

This study discusses the similarities and differences between the antifungal activity of extracts from walnut green husks of Lake, Koszycki, UO1, UO2 and non-grafted cultivars as well as juglone against the plant pathogenic fungi such as Alternaria alternata, Rhizoctonia solani, Botrytis cinerea, Fusarium culmorum, Phytophthora infestans as well as Ascosphaera apis causing chalkbrood disease in honey bees. The obtained data show that the antifungal activities of the extracts do not always depend on the antifungal activity of juglone, and that they can be modulated by their other components. This fact allows us to conclude that juglone is not the only component of walnut green husk extracts which is responsible for the inhibition of mycelial growth. Phenolic compounds were found to be responsible for activity of the extracts and they can modify antifungal activity of juglone.

Impact of molecular mutations on treatment response to DNMT inhibitors in myelodysplasia and related neoplasms.

We hypothesized that specific molecular mutations are important biomarkers for response to DNA methyltransferase inhibitors (DNMT inhibitors) and may have prognostic value in patients with myelodysplastic syndromes (MDS). Mutational analysis was performed in 92 patients with MDS and related disorders who received 5-azacytidine (n=55), decitabine (n=26) or both (n=11). Mutational status was correlated with overall response rate (ORR), progression-free survival (PFS) and overall survival (OS) by univariate and multivariate analysis. Risk stratification models were created. TET2, DNMT3A, IDH1/IDH2, ASXL1, CBL, RAS and SF3B1 mutations were found in 18, 9, 8, 26, 3, 2 and 13% of patients, respectively. In multivariate analysis, TET2(MUT) and/or DNMT3A(MUT) (P=0.03), platelets > or = 100 × 10(9)/l (P=0.007) and WBC<3.0 × 10(9)/l (P=0.03) were independent predictors of better response. TET2(MUT) and/or DNMT3A(MUT) (P=0.04) status was also independently prognostic for improved PFS, as were good or intermediate cytogenetic risk (P<0.0001), age<60 (P=0.0001), treatment with both 5-azacytidine and decitabine (P=0.02) and hemoglobin > or = 10 g/dl (P=0.01). Better OS was associated with ASXL1(WT) (P=0.008) and SF3B1(MUT) (P=0.01), and, similar to PFS, cytogenetic risk (P=0.0002), age (P=0.02) and hemoglobin (P=0.04). These data support the role of molecular mutations as predictive biomarkers for response and survival in MDS patients treated with DNMT inhibitors.

13C-methacetin breath test correlates with clinical indices of liver disease severity in patients with primary biliary cirrhosis.

This prospective study intended to ascertain if cytochrome P450 dependent liver function is affected in early and late histological stages of primary biliary cirrhosis (PBC). The study included 32 female PBC patients (mean age 55.4 years, range 33-70) and 16 aged-matched healthy women (mean age 52.6 years, range 38-65). In every subject a 13(C)-methacetin breath test (13(C)-MBT) was applied, and the results were related to histological Ludwig's staging system and several indices of liver disease severity comprising the MAYO-1, MAYO-2, MELD, and Child-Pugh score. The 13(C)-MBT differentiated healthy controls from the patients with Ludwig IV and Ludwig III histopathological stages of PBC. The most significant relationships (i.e. explaining >50% of the variance) were found between measurements of the momentary breath 13(C) elimination from 6 to 18 minutes as well as the 15-min or 30-min cumulative elimination and the MAYO-1 or MAYO-2 scores. The breath test poorly correlated with histopathological features of PBC, however, it accurately discriminated cirrhotic from non-cirrhotic patients (momentary breath 13(C) elimination at 40 min, AUROC 0,958). In conclusion, 13(C)-MBT correlates with clinical scoring systems, especially those specifically designed for PBC (Mayo model) and accurately recognizes the disease at the stage of cirrhosis up to 40 minutes of the test duration.

Multiple mechanisms deregulate EZH2 and histone H3 lysine 27 epigenetic changes in myeloid malignancies.

Polycomb repressive complex 2 (PRC2) is involved in trimethylation of histone H3 lysine 27 (H3K27), chromatin condensation and transcriptional repression. The silencing function of PRC2 complex is mostly attributed to its intrinsic activity for methylating H3K27. Unlike in B-cell lymphomas, enhancer of zeste homolog 2 (EZH2) mutations in myeloid malignancies are inactivating/hypomorphic. When we assessed the mutational status in myeloid malignancies (N=469 cases examined), we found EZH2 and EED/SUZ12 mutations in 8% and 3.3% of cases, respectively. In addition to mutant cases, reduced EZH2 expression was also found in 78% cases with hemizygous deletion (-7/del7q cases involving EZH2 locus) and 41% of cases with diploid chromosome 7, most interestingly cases with spliceosomal mutations (U2AF1/SRSF2 mutations; 63% of cases). EZH2 mutations were characterized by decreased H3K27 trimethylation and increased chromatin relaxation at specific gene loci accompanied by higher transcriptional activity. One of the major downstream target is HOX gene family, involved in the regulation of stem cell self-renewal. HOXA9 was found to be overexpressed in cases with decreased EZH2 expression either by EZH2/spliceosomal mutations or because of -7/del7q. In summary, our results suggest that loss of gene repression through a variety of mutations resulting in reduced H3K27 trimethylation may contribute to leukemogenesis.

The effect of exogenous apelin on the secretion of pancreatic juice in anaesthetized rats.

Apelin is known to stimulate cholecystokinin (CCK) and inhibit insulin release, however the mechanisms on pancreatic secretion remain unclear. The present study aimed to determine the expression of apelin and apelin receptor in the pancreas by immunofluorescence studies and the effect of exogenous apelin on the secretion of pancreatic juice in anesthetized rats. Pancreatic-biliary juice (P-BJ) was collected from Wistar rats treated with apelin (10, 20 and 50 nmol/kg b.w., boluses given every 30 min intravenously or intraduodenaly). The same apelin doses were administered to rats subjected to intraduodenal tarazapide, capsaicin or vagotomy. Pancreatic blood flow was measured by a laser doppler flowmeter. Direct effects of apelin were tested on dispersed acinar cells. Apelin receptor was expressed on acinar cells, pancreatic duct and islets cells, whereas apelin in pancreatic acini, but not in the islets. Intravenous apelin decreased P-BJ volume, protein and trypsin outputs in a dose-dependent manner. In contrast, intraduodenal apelin stimulated P-BJ secretion. Pharmacological block of mucosal CCK(1) receptor by tarazepide, vagotomy and capsaicin pretreatment abolished the effects of intravenous and intraduodenal apelin on P-BJ volume, protein and tryspin outputs. Apelin decreased the pancreatic blood flow. Apelin at 10(-6) M increased the release of amylase from non-stimulated and CCK-8-stimulated acinar cells. In conclusion, apelin can affect the exocrine pancreas through a complex mechanism involving local blood flow regulation and is driven by vagal nerves.

CpG methylation patterns and decitabine treatment response in acute myeloid leukemia cells and normal hematopoietic precursors.

The DNA hypomethylating drug decitabine maintains normal hematopoietic stem cell (HSC) self-renewal but induces terminal differentiation in acute myeloid leukemia (AML) cells. The basis for these contrasting cell fates, and for selective CpG hypomethylation by decitabine, is poorly understood. Promoter CpGs, with methylation measured by microarray, were classified by the direction of methylation change with normal myeloid maturation. In AML cells, the methylation pattern at maturation-responsive CpGs suggested at least partial maturation. Consistent with partial maturation, in gene expression analyses, AML cells expressed high levels of the key lineage-specifying factor CEBPA, but relatively low levels of the key late-differentiation driver CEBPE. In methylation analysis by mass spectrometry, CEBPE promoter CpGs that are usually hypomethylated during granulocyte maturation were significantly hypermethylated in AML cells. Decitabine-induced hypomethylation was greatest at these and other promoter CpGs that are usually hypomethylated with myeloid maturation, accompanied by cellular differentiation of AML cells. In contrast, decitabine-treated normal HSCs retained immature morphology, and methylation significantly decreased at CpGs that are less methylated in immature cells. High expression of lineage-specifying factor and aberrant epigenetic repression of some key late-differentiation driver genes distinguishes AML cells from normal HSCs, and could explain the contrasting differentiation and methylation responses to decitabine.

Maternal smoking decreases antioxidative status of human breast milk.

OBJECTIVE: To evaluate the influence of maternal smoking on antioxidative capacity and intensity of oxidative damage in breast milk. STUDY DESIGN: The study group (n=30) was comprised of postpartum women who declared smoking more than five cigarettes per day during pregnancy and lactation (confirmed by the urinalysis of cotinine concentration), and their newborns. Control group included 29 non-smoking postpartum women and their newborns. Colostrum samples were collected on the 3rd day after delivery and breast milk samples between the 30th and the 32nd day after delivery. Morning maternal and neonatal urine samples were obtained on the day of the mature milk sampling. Isoprostane concentrations in colostrum/mature milk and urine were determined immunoenzymatically. Total Antioxidant Status (TAS) of colostrum/breast milk was determined by Rice-Evans and Miller method. RESULT: Colostrum TAS in smokers was significantly lower than in non-smokers (P=0.006). In both groups, the TAS of mature milk was higher compared with colostrum, but significant differences were observed amongst smokers only (P=0.001). In smokers the isoprostane concentration of mature milk was significantly higher than the colostrum concentration (P=0.001). Significant inverse correlation between maternal urinary isoprostane concentration and the TAS of mature breast milk was observed in smokers (R=-0.525, P=0.023), but not in non-smokers (R=0.161, P=0.422). CONCLUSION: This study revealed that maternal smoking triggers harmful effects on an infant by impairing pro-oxidant-antioxidant balance of breast milk.

Cyanines as efficient photosensitizers in photodynamic reaction: photophysical properties and in vitro photodynamic activity.

The purpose of the present study was to explore the potential application of cyanines in photodynamic treatment. The photophysical features of four cyanines (KF570, HM118, FBF-749, and ER-139) were investigated by elemental and spectral analyses. Two malignant cell lines (MCF-7/WT and MCF-7/DOX) were used to test the potential for use in the photodynamic therapy. The cytotoxic effects of these dyes were determined by the MTT assay after 4 and 24 h of incubation with the cyanine. KF570 and HM118 were irradiated with red light (630-nm filter) and FBF-749 and ER-139 with green light (435-nm filter). The results showed that the cyanine HM118 demonstrated a major phototoxic effect. It was also noted that the efficiency of photodynamic therapy was higher in the doxorubicin-resistant cell line (MCF-7/DOX).

Coexpression of human chorionic gonadotropin beta subunit and its receptor in nontrophoblastic gynecological cancer.

A considerable number of biochemical and physiologic studies evaluate the roles of gonadotropins in carcinogenesis. Latest reports show that human chorionic gonadotropin (hCG), and especially its beta subunit, are secreted by a variety of malignant tumors of different origin. However, the mechanism of hCG action and its role in tumor development is not known yet. This study, with the help of reverse transcription-polymerase chain reaction and immunohistochemistry, is an attempt to document the molecular presence of the hCGbeta and luteinizing hormone/hCG receptor (LH/hCGR) in the ovarian, endometrial, and uterine cervix cancer tissues. The LH/hCGR, coexpressed with hCGbeta, may act as a potential mediator of hCG action in nontrophoblastic gynecological cancers.

Intestinal MMC-related electric fields and pancreatic juice control the adhesion of Gram-positive and Gram-negative bacteria to the gut epithelium--in vitro study.

The adhesion of six different Lactobacillus and Lactococcus and three pathogenic Escherichia and Salmonella strains was studied using Caco-2 cell line. In this in vitro model system the influence of weak electric field (EF) on bacterial adhesion was tested. The EF source was the in vitro reconstruction of spiking potentials recorded in the duodenum of a healthy calf during one myoelectrical migration complex (MMC) cycle. The ability to adhere to Caco-2 cells of bacteria belonging to two groups, Gram-positive lactobacilli and lactococci, and Gram-negative Escherichia and Salmonella differed considerably. The pathogenic bacteria adhered better to well-differentiated Caco-2 cells whereas lactobacilli and lactococci displayed better adhesion to non-differentiated Caco-2 cells. In the presence of MMC-related EF an increased adhesion of Lactobacillus and Lactococcus but not of Salmonella enterica s. Enteritidis and E. coli 269 to Caco-2 cells was observed. Two later strains adhered even less in the presence of EF. The same tendency was found in the presence of pancreatic juice in a cell medium. In conclusion, the myoelectric component of the small intestinal motility, the MMC-related EF, and pancreatic juice may increase the ability of lactic acid bacteria to adhere to GI epithelial cells, creating better environmental conditions for colonization of the intestine and competition with Gram-negative pathogens.

Base excision repair dysfunction in a subgroup of patients with myelodysplastic syndrome.

In myelodysplastic syndromes (MDS) increased chromosomal breaks point toward defects in DNA repair machinery including base excision repair (BER) pathway involved in handling of oxidative DNA damage. We investigated whether defects in this pathway can be found in MDS. Elevated levels of 8-oxoguanine (8-OG) were found in a significant proportion of MDS patients, indicating increased oxidative DNA damage or defective handling of oxidative load. In a distinct subgroup of patients, increased 8-OG content was associated with increased hOGG1 mRNA expression and activity. In some patients, increased numbers of abasic sites (AP sites) correlated with low levels of POLbeta. To further investigate the nature of this defect, we examined genetic lesions potentially explaining accumulation of 8-OG and AP sites. We genotyped a large cohort of MDS patients and found a correlation between increased oxidative damage and the presence of the hOGG1-Cys326 allele suggesting inadequate compensatory feedback. Overall, this hOGG1 variant was more frequent in MDS, particularly in advanced forms, as compared to controls. In summary, we demonstrated that BER dysfunction in some MDS patients may be responsible for the increased 8-OG incorporation and explains one aspect of the propensity to chromosomal breaks in MDS but other mechanisms may also be involved.

Obestatin stimulates the secretion of pancreatic juice enzymes through a vagal pathway in anaesthetized rats - preliminary results.

Obestatin is a 23 amino acid peptide derived from the preproghrelin precursor, and originally purified from the rat stomach mucosa. It was shown that obestatin may counteract the effects of its sister peptide, ghrelin, on food intake and gastrointestinal motility but the other roles in controlling the gastrointestinal function remain unknown. The aim of the present study was to determine the influence of exogenous obestatin on the secretion of pancreatic juice. In anesthetized male Wistar rats the external jugular vein was catheterized, and the common biliary-pancreatic duct was cannulated with polyethylene tubing for collection of pancreatic-biliary juice (P-BJ). Obestatin boluses (30, 100 and 300 nmol/kg b. wt.) were injected intravenously or intraduodenally every 30 min. Obestatin was also administered in vagotomized (subdiaphragmatic vagotomy) rats. In the examined rats, obestatin intravenous and intraduodenal boluses did not affect the P-BJ volume. On the other hand, obestatin boluses increased the protein output and trypsin activity. Vagotomy abolished the effects of exogenous obestatin administration. In conclusion, the present study demonstrates for the first time that exogenous obestatin may stimulate the secretion of pancreatic juice enzymes. The effect is dose-dependent and requires intact vagal supply.

Donor-origin cell engraftment after intraosseous or intravenous bone marrow transplantation in a rat model.

We compared the effects of intraosseous BMT with those of standard i.v. BMT on the efficacy on donor-cell engraftment into the BM and lymphoid organs across an MHC barrier in rats. Twenty-four intraosseous and 24 i.v. BMTs were performed from 48 ACI (RT1(a)) donors to 48 Lewis (RT1(l)) recipients. Each transplant group received either intraosseous or i.v. BMT. Groups I and II served as controls without immunosuppression (n=16); groups III and IV received cyclosporine monotherapy (n=16); and V and VI received alphabeta-TCR monoclonal antibody and cyclosporine A (alphabeta-TCR/CsA) for 7 days (n=16). In each group, four rats received 35 x 10(6) transplanted bone marrow cells (BMCs) and four received 70 x 10(6) cells. All animals survived without GVHD. Mean (+/-s.d.) donor-cell engraftment into BM of recipients after intraosseous BMT was 7.9% (+/-1.3%) in recipients receiving alphabeta-TCR-CsA and 70 x 10(6) BMCs, and 4.2% (+/-1.4%) in recipients after i.v. transplantation. The seeding efficacy of donor cells into lymphoid tissue was greater after intraosseous BMT and alphabeta-TCR-CsA than after standard i.v. transplantation. In our model, intraosseous BMT facilitated donor-cell engraftment under short-term immunodepletive alphabeta-TCR/CsA protocol, which resulted in a temporary state of immune unresponsiveness.

Low frequency of the CHEK2*1100delC mutation among breast cancer probands from three regions of Poland.

The 1100delC germline mutation of the CHEK2 gene appears to contribute significantly to the overall breast cancer incidence in some West and North European countries, but seems to be much less frequent among breast cancer patients from other regions of Europe. In the present study we found, respectively, 3/487, 1/296 and 0/279 carriers of this mutation among breast cancer patients from the East-Central, South-East and West-Central regions of Poland. Two carriers of the 1100delC mutation were found among 120 patients with bilateral breast cancer, but only one had a previous family incidence of breast cancer. We found no carriers among 182 patients with unilateral breast cancer with family history of this tumor and among 64 patients with breast cancer and a second primary tumor at an other site. We conclude that the 1100delC mutation of the CHEK2 gene contributes little to the overall breast cancer burden in Poland, including familial cases of this malignancy. Further studies are still needed to evaluate the contribution of this mutation to the development of bilateral breast tumors.

PTEN mutation, expression and LOH at its locus in ovarian carcinomas. Relation to TP53, K-RAS and BRCA1 mutations.

OBJECTIVE: We aimed to evaluate frequency of PTEN mutation, LOH and expression in ovarian tumors. In search for a molecular pathway, we confronted PTEN gene mutations with TP53, K-RAS and BRCA1 gene status in the same tumors. We also evaluated clinical significance of PTEN expression in a subgroup of patients uniformly treated with platinum-based regimens. METHODS: Molecular analysis was performed on 105 ovarian tumors (100 carcinomas) with the use of the SSCP and sequencing. Seventy-six tumors were analyzed for LOH at 10q23 locus with the use of six polymorphic markers. Immunohistochemical PTEN expression was done on paraffin-embedded material. Multivariate and univariate analysis was performed with the STATA program. RESULTS: PTEN mutations occurred in 5/100 (5%) of all carcinomas and in 3/15 (20%) of endometrioid carcinomas (EC). Low-grade EC that developed in borderline tumors had PTEN and/or K-RAS mutation (4/5, 80%), while high-grade EC had TP53 mutations only. There was a reverse association between PTEN and TP53 mutations (P = 0.005). LOH at PTEN locus was found in 60% of endometrioid and in 28% of serous and clear cell carcinomas. PTEN expression did not associate with PTEN mutations or LOH. Strong PTEN expression diminished risk of death in a TP53 positive group only (HR = 0.35, P = 0.029). CONCLUSION: Our results suggest that PTEN mutations may play a role in a development of low-grade endometrioid tumors. PTEN haploinsufficiency caused by LOH or epigenetic events may possibly contribute to development of other histological types and may be an adverse prognostic factor.

The evaluation of lysozyme concentration and peroxidase activity in non-stimulated saliva of patients infected with HIV.

PURPOSE: The aim of the study was the comparison of lysozyme concentration and peroxidase activity in mixed, non-stimulated saliva of HIV-positive patients and healthy subjects. MATERIAL AND METHODS: The study was carried out in the group of 37 patients infected with HIV. The control group comprised of non-infected individuals, counterpart of the examined group. Mixed non-stimulated saliva, collected using expectoration method in the amount of 3-5 ml 2 hours after meal, was used for the study. Saliva samples were centrifuged, divided into portions 200 microl each, and stored at -80 degrees C. Peroxidase activity was determined using the method by Mansson-Rahemtull et al. Lysozyme concentrations were determined with the use of radial immunodiffusion method, ready-made kits (Human NL Nanorid plate--The Binding Site Ltd., UK). RESULTS: Higher concentrations of lysozyme as well as peroxidase activity were observed in the group of patients with HIV as compared to the control group, and they were 35.08 microg/ml, 46.74 IU/1, 21.3 microg/ml, 37.73 IU/l, respectively. The difference was statistically significant only in case of peroxidase activity. CONCLUSIONS: 1. HIV infection triggers immune mechanisms, that are manifested by the increase in salivary enzymes responsible for local non-specific resistance. 2. The immunological resistance decrease, manifested by the drop of the absolute number of CD4 lymphocytes T, is compensated by the increase in lysozyme concentration and peroxidase activity in non-stimulated saliva of HIV-positive patients.

The saliva immunology mechanisms and periodontal status in HIV infected subjects.

PURPOSE: The aim of this study was the evaluation of connection between parodontium determined by using GI and PBI indexes and specific immunity status and non-specific in HIV infected group and in control group. MATERIAL AND METHODS: The study was carried out in the group of 37 patients infected with HIV. Mixed non-stimulated saliva was used for the study. Peroxidase activity was determined using the method by Mansson-Rahemtull. Lysozyme and A, G, M antibodies concentrations were determined with the use of radial immunodiffusion method. The concentration of lactoferrin was determined by using ELISA method. The clinical state of parodontium estimated by means of GI and PBI evaluating quality changes in the gum. RESULTS: Deterioration of the immunological status of subjects was accompanied by the increase of the values of GI and PBI. The strong negative correlation between GI and PBI and the concentration of lactoferrin and positive activity of the peroxidase in the whole examined population was determined. In the infected group the correlation between the status of gingiva expressed by GI and concentration or activity of examined enzymes and immunoglobulins was not ascertained. CONCLUSIONS: 1. HIV infection is connected to worsening of paradontium status expressed by values of GI and PBI indexes. 2. Paradontium status correlated positively with immunological status of HIV positive subjects. 3. In HIV infected group, no connection between number of IgA, IgG, IgM, concentration of lysozyme, lactoferrin, activity of peroxidase and paradontium status was observed.